MXPA96002492A - Hydraulic drive and control system - Google Patents

Abstract

A switching valve has a control rod with a pilot chamber at each of its ends. For each pilot chamber, there is a first passageway connected to a pressure line and communicating with the pilot chamber. A second passageway is connectable to return. A relief valve has a valve member biased to close an orifice to close communication between the pilot chamber and the second passageway. The valve member has an open position in which the pilot chamber is connected to return via the second passageway to allow shifting of the control rod. In a first embodiment, the pilot chamber is continuously in communication with pressure via the first passageway, and the valve member is opened by this pressure is response to connection of the second passageway to return. In another embodiment, the second passageway is continuously in communication with return, and the valve member is mechanically moved into its open position by an operator in response to pressure acting on the operator. A four-way directio nal control valve controls branch conduits leading from the switching valve to drive motors.

Description

HYDRAULIC CONTROL AND OPERATING SYSTEM Technical Field The present invention relates to hydraulic control and drive systems and, more particularly, to a bypass or 3-way valve in such a system, which has a safety or discharge valve at each of the opposite ends of a busbar. control to selectively communicate with a pilot camera at the end of the control bar to return to the initial position, and a four-way directional control valve that opens and closes the branch lines connecting a bypass valve and the opposite ends of the drive motors.

Information from the Background Bypass or 3-way valves are used in various types of hydraulically operated systems to change the connections that communicate the pressure and to return to the initial position during or at the end of an operating cycle. A type of system that uses bypass or three-way valves is a control and drive system for a transport mechanism.

Ref. 22699 floor with alternative movement. An example of a hydraulic control and drive system for a reciprocating floor conveyor device as described in U.S. Pat. No. 5,193,661 of the same applicant, issued March 16, 1993 and entitled "System of Linear Hydraulic Motors" ("System of Linear Hydraulic Motors"). The described conveyor device is of a type in which each of the three sets of slats or floor slats is connected to a respective drive motor. The three drive motors are operated to move the floor slats or slats simultaneously in a first transport direction and then move the slats or slats sequentially in the opposite direction and thereafter repeat the cycle until the transportation operation is completed. The described system has a bypass or three way valve to alternately supply a pressure to the opposite ends of the motors to cause the movable portions of the motors to move in both directions. In U.S. Pat. No. 5,103,866, of the same applicant, granted on April 14, 1992, describes a valve which can be used as a bypass valve or three-way valve in a control and drive system for a floor conveyor with alternating movement -tive and which has a control bar that is mechanically operated by contact with the supports or butt joints carried by the motors or elements connected to it. The control and drive systems for the reciprocating floor conveyor devices typically have means for controlling the operating direction of the drive motors to carry a load in either of the two opposite directions. An example of a directional control valve is one that is described in U.S. Pat. No. 5,361,679, granted on November 8, 1994, by the same applicant. This valve is also shown in U.S. Pat. No. 5,375,619, granted on December 27, 1994, by the same applicant.

Brief Description of the Invention An object of the present invention is an improvement in a bypass or three-way valve of a type having a two-position control rod with a pilot chamber at each of its ends. According to one aspect of the invention, the improvement comprises, for each pilot chamber, a first passage, a second passage, and a safety or desire valve. The first passageway is connected to a line or pipe under pressure and communicates with the respective pilot camera. The second passage can be connected to return to the starting position. The safety or discharge valve has a valve element biased or tilted to close a hole, to interrupt communication between the pilot chamber and the second passageway. The valve member has an open position in which the pilot chamber is connected to establish a return path through the second passageway to allow displacement of the control rod. When used here, the term "line or pressure pipe" means a passageway or conduit that is connected to a source of pressure when the system in which the bypass valve is incorporated, is in operation. Accordingly, the first passageway is always in communication with the pressure unless the same or the pressure line is blocked, such as by a safety or discharge valve. In a first embodiment of the bypass valve, the pilot chamber, when in use, is in continuous communication with the pressure through the first passageway. The valve element is moved to its open position by the pressure in response to the connection of the second passage to return to the initial position. Preferably, a restriction in the first passage allows the pressure to move outwardly from the pilot chamber through the orifice, faster than the pressure can move toward the pilot chamber through the first passageway. In another embodiment, an operator is positioned to couple the valve element. The second passageway is, when in use, in continuous communication with the return path. The valve element is mechanically moved towards its open position by the active part in response to the pressure acting on the active part. According to another aspect of the invention, the improvement in the bypass or three-way valve comprises, for each pilot chamber, a first passage, a second passage, a safety or discharge valve, and a conduit. The first passage can be connected to the pressure and communicates with the pilot camera. The second passage is connected to the return path. The safety or discharge valve includes a deflected or inclined valve element for closing a hole, to stop or close the communication between the second passageway and the pilot chamber. It also includes an active part having a first end positioned to couple the valve element and a second end with a piston or piston formed thereon. The conduit establishes the communication of the first passage for the pilot chamber with the piston or plunger of the safety valve or discharge for the other pilot chamber. The pressure in the first passage for one of the pilot chambers is communicated to the pilot chamber and to the piston or plunger of the safety valve so that the other pilot chamber moves the piston or piston and mechanically disengages the valve element. This connects to the other pilot camera to establish the return path and allows the pressure in the first of the pilot cameras to move the control rod. The last described aspect of the improvement in the bypass or three-way valve can be provided in combination with a plurality of drive motors. Each motor has a movable portion that carries a support or butt joint. First and second check or braking valves are included, one for each of the first passages. Each check or braking valve has a valve element biased or tilted towards a closed position in which it blocks the corresponding first passage. The check or braking valve also has an active part positioned to be coupled by one of the abutments or abutments, to mechanically disengage the valve member from the check valve and connect the first passage corresponding to the pressure. Preferably, each check valve is, during use, continually connected to the pressure acting on the valve element, of the check valve, to deflect it to its closed position. Also preferably, the bypass or three-way valve is operatively connected to the motors to bypass the pressure and return it between the first and second supply conduits, leading to the motors causing the movable portions of the motors to move in alternative way According to another aspect of the invention, the bypass or three-way valve has a return opening as well as the two-position control rod, and the machine comprises a safety valve for each pilot chamber. The return opening may be a single opening or may include a plurality of openings. The safety valve has a cavity for the valve divided by a hole in first and second valve chambers communicating with the corresponding pilot chamber and the return opening, respectively. A valve element in the first chamber of the valve is diverted or polarized to close the orifice. A piston or plunger is slidably received in the cavity for the valve spaced from the orifice to partially define the second chamber of the valve. A rod of the active part or operator extends from a first end of the piston or piston towards the second chamber of the valve and the hole for coupling and unfastening the valve element in response to the movement of the piston or plunger towards the orifice. One conduit communicates to the first valve chamber of each safety valve with a second opposite end of the piston or piston of the other safety valve. The pressure communicated to one of the pilot chambers by means of the first valve chamber, of the respective safety valve, is also communicated to the second end of the piston or piston of the other safety valve, to disentangle the valve element. , of the other safety valve and by which the other pilot chamber is connected to the return path. This allows the pressure in the first of the pilot cameras to move the control bar. The improved three-way or bypass valve is preferably provided in combination with a pressure line for each of the first valve chambers connecting the first valve chamber to the pressure, and to a plurality of drive motors. Each motor has a movable portion that carries a support or butt joint. First and second check valves are provided, one for each line or pressure line. Each check valve has a valve element biased or biased towards a closed position in which it blocks the pressure line. An active part is arranged to be coupled by one of the abutments or butt joints to mechanically disengage the valve element from the check valve and connect the first chamber of the valve corresponding to the pressure. As described above, the check valve is preferably continuously connected to the pressure which tilts or deflects its valve element towards the closed position. The improved bypass or three-way valve of the invention can be used in various types of hydraulic systems or other pressure operated systems. The operation of the valve is effective and reliable to provide an effective and reliable operation of the system in which the valve is incorporated. The structure of the valve improvements, including the safety valves, is relatively simple, and the valve can be manufactured and maintained in an effective manner in terms of cost. A primary advantage of the bypass or three-way valve of the invention, compared to three-way bypass valves or mechanically operated valves, is that, during use, the bypass or three-way valve never or almost never needs adjustment. This helps reduce maintenance and operational costs of the system. The embodiments of the invention that include the preferred combinations described above have the additional advantage of making it possible to minimize the number of components of the entire system without sacrificing the reliability and effectiveness of the system. Another object of the invention is a four-way valve in combination with additional elements in a control system for a reciprocating floor conveyor device of a type having a plurality of floor slats and a plurality of drive motors. operated with a pressurized fluid to move the slats or slats of the floor in an alternative way. The combination comprises first and second conduits, a bypass or three-way valve, and the four-way valve. Each of the conduits has a main portion leading to the engines, and a branch portion. The bypass or three-way valve alternately connects the ducts to the pressure and then to the return path to alternately move the floor slats or slats. The four-way valve has first and second openings communicating with the bypass portions of the first and second conduits, respectively. The valve also has third and fourth openings that communicate with the opposite ends of the motors. The four-way valve has a first position in which it connects the first opening with the third opening and blocks communication between the second and fourth openings to cause the conveyor device to carry a load in a first direction. In a second position, it blocks communication between the first and third openings and connects the second and fourth openings to cause the conveyor device to transport a load in a second opposite direction. The four-way valve of the combination described above has the advantages that it is of a simple construction and that it helps reduce the number of connections in the control system. It can advantageously be provided in additional combination with the type of bypass or three-way valve described above. These and other advantages and features will become apparent from the detailed description of the best modes for carrying out the invention as follows.

Brief Description of the Drawings Similar numerical references are used to designate like parts in all the various views of the drawings, and: Figure 1 is a longitudinal sectional view of a pressure return bypass valve that is a part of a first embodiment of the present invention Figure 2 is a fragmentary view, partly in longitudinal section and partly in elevation, of a check valve which is a part of the invention, such valve is biased to a closed position by a spring and can be opened by a force of a pressure difference acting on the valve plug as opposed to the spring and by a mechanical force applied to the valve plug in opposition to the spring. Figure 3 is a schematic diagram of three linear hydraulic motors and a control system to automatically control the hydraulic fluid pressure to and from the working chambers of the motors, such view shows the various valves placed to cause a simultaneous movement of the three engines in the direction of the arrow labeled "discharge." Figure 4 is a view similar to that of Figure 3, but showing the three motors at one end of the travel position, and showing several valves placed to initiate a return sequence of the motors. Figure 5 is a view similar to that of Figures 3 and 4, but showing a first of the engines returned to its starting position and a valve opening which activates or triggers the next step of the sequence. Figure 6 is a view similar to that of Figures 3-5, but showing a second of the motors returned to their starting position and the opening of a valve which activates the next step of the sequence. Figure 7 is a view similar to that of Figures 3-6, but showing a directional valve moved to cause reverse operation of the engines, and showing all three engines placed in a new starting position, and several valves placed to cause a simultaneous movement of all three engines to a new advanced position. Figure 8 is a view similar to the. of Figure 7, but showing the totality of the three motors moved from the start position to the advanced position and showing several valves positioned to activate the next step of the sequence. Figure 9 is a view similar to that of Figures 7 and 8, but showing one of the motors returned to its starting position and the opening of the valve that activates the next step of the sequence. Figure 10 is a view similar to that of Figures 7-9, but showing a second of the motors returned to their starting position and the opening of the valve that activates the next step of the sequence. Figure 11 is a schematic diagram of an alternative form of the three engines and associated valves and conduits, showing each engine in an intermediate position. Figure 12 is a view similar to that of Figure 1, but showing another embodiment of the bypass or three-way valve.

Best Way to Carry Out the Invention The drawings show the bypass or three-way valves 10, 10 'and associated safety valves VI, V2, VI', V2 ', and a hydraulic control and drive system, which are constructed in accordance with the invention and which constitute the best modes for carrying out the invention commonly known by the applicant. The system of the invention is mainly proposed for use in supplying power to the slats or conveyor slats of a conveyor device with reciprocating slats. The system illustrated here is designed for use in a reciprocating slat conveyor device having three groups of slats, with each group being supplied with power by a separate hydraulic motor. The U.S. Patent No. 4, 793,469 of the same applicant, describes the operation of such conveyor device. Particular reference is made to Figures 2-6 of this patent, which illustrate the movements of the slats during the operation of the conveyor device. Referring to Figure 1 of the present application, the first illustrated embodiment of the invention includes a bypass or three-way valve 10. The valve 10 is basically similar to the valve that is described in U.S. Pat. No. 5,103,866 of the same applicant (Figures 7-16) except that the control rod 12 is hydraulically displaced longitudinally instead of mechanically. One difference is that the valve 10 of the invention has a five-part housing while the valve described by U.S. Pat. No. 5,103,866 has a three-part housing. The parts of the valve housing 10 are screwed together in the manner described by U.S. Pat. No. 5,103,866 (for example, Figure 11). Attached to the valve 10 of the present invention are the end portions 14, 16 of the housing. The end part 14 is moved longitudinally outward of the intermediate part 18. The end part 16 is moved longitudinally outward of the intermediate part 20. The part of the center 22 is interposed between the intermediate parts 18, 20. The ring seals in 0 are used between the parties to prevent leaks or run-off. The construction and arrangement of the 0-ring seals is shown in U.S. Pat. No. 5,103,866 and therefore it is not repeated here. A trephine or other tool is used to form the passages 24, 26 in the end portions of the control rod 12. A larger diameter orifice is formed outwardly of each passageway 24 ', 26. The closing beads 28, 30 they are positioned in these holes and the plugs 32, 34 are positioned outwardly of the closing balls 28, 30. The holes are internally threaded and the plugs 32, 34 are externally threaded. The plugs 32, 34 are externally threaded. The plugs 32, 34 are tightly screwed against the closure balls 28, 30 to form end-enclosures or fluid-tight ends for the passages 24, 26. The lifting or moving head elements 36, 38 are placed on and are supported by the control rod 12, in the same manner as described in U.S. Pat. No. 5,103,866. The internally confronting elements of the lifting elements 36, 38 are separated by a small space and are always exposed to the pressure in an inlet opening 40 of the valve 10. The opposite end of each lifting element 36, 38 has a piston or piston formed on it. The details of the elevating elements 36, 38 will not be described in detail here because such details are described very well in U.S. Pat. No. 5,103,866. A pump P supplies the pressure of the hydraulic fluid to the inlet opening 40. The branch lines 42, 44 supply the fluid pressure through the distribution openings 46, 48. The return openings 50, 52 are connected to the ducts 53, 54 which return to the tank, as shown schematically in Figure 1. The return opening 50 is connected via the passageway 55 to the opening 56, to the passageway 58, to the opening 60, and to the passageway 62. The return opening 52 is connected by passageway 64 to opening 66, passageway 68, opening 70, and passageway 72. Opening 60 and opening 70 each open on the longitudinal cavity in which the bar Control 12 is reciprocated between two annular notches, to provide an escape for any fluid that could be filtered by passing the seals (not shown) placed in the samples. The pairs of seals help to maintain a smooth operation of the control rod 12. The pilot chambers 74, 76 are formed longitudinally outward of the two ends of the control rod 12. The pilot chamber 74 is connected to a conduit 78 by a passageway 80, a valve chamber 82, a safety valve VI, and a passageway 84. The pilot chamber 76 is connected to a conduit 86 by a passageway 88, a valve chamber 90, of a relief valve V2 , and a passageway 92. The safety valve VI has a valve cavity divided by a hole in the first and second chambers 82, 83 of the valve. The valve chamber 82 contains a closure ball 94 and a spring 96 which deflects or tilts the closure ball 94 into a position in which it closes the orifice. The ball 94 of the valve is confronted by a portion of rod 102 of an active part which mechanically deasures the ball 94 of the valve. As shown in Figure 1, the end of the rod 102 extends through the hole. The external diameter of the rod 102 is smaller than the diameter of the hole. Accordingly, when the ball 94 is disengaged, the fluid pressure can move through an annular passage formed around the stem 102. The end of the rod 102 opposite the ball 94 is fixed to a piston or plunger 104. The end of the plunger rod or piston 104 communicates with the return passage 62 through the valve chamber 83 and defines an end of the chamber 83 of the valve. The opposite end of the piston or plunger 104 is connected to a passageway 106. The passageway 106 extends to and is connected to the passageways 86, 92. In the relief valve V2, the valve cavity is divided by a first-order orifice. and second chamber 90, 91 of the valve. A closing ball 98 in the chamber 90 is deflected or tilted by the spring 100 to close the hole. The closing ball 98 is confronted by a rod 108 which is connected to a piston or piston 110. The end of the rod of the piston or piston 110 is connected to the return passage 72 by means of the chamber 91 of the valve. The opposite end of the piston or plunger 110 is connected to the passage 112 which leads beyond and is connected to the passageways 78, 84. Since the end of the rod of each piston or plunger 104, 110 is always connected to the path of return, which connects the opposite end of the piston 104, 110 under pressure, will cause the piston or plunger 104, 110 to move to dislodge the ball 94, 98. The bypass or three way valve 10 includes two distribution openings 114, 116, which are connected to the ducts of distribution 118, 120. In a position of the bypass or three-way valve 10, the conduit 118 is connected to the return path or to the tank and the conduit 120 is connected to the pressure. In the second position of the bypass valve 10, the conduit 118 is connected to the pressure and the conduit 120 is connected to the return path. Here, the terms "conduit", "catwalk", "opening" and "line" are used to mean any of a number of structures which contain, conduct or transfer a hydraulic fluid. They can take the form of pipes, hoses, perforated passages, etc.

Referring to Figures 3-10, the V3 valve is a two-way, four-way valve. Its function is to control the direction in which the system carries a load. This is effected by selectively opening and closing the communication between the distribution conduits 118 and 120 and the portions of the valves V4-V9 and the motors M1-M3, as described below. The valves V4, V5, V6, V7, V8, V9 are double valves. As will be described, each is of the nature of a check valve that is normally closed by the actuation with a spring. The pressure of the fluid through the valve in opposition to the force of the spring will open the valve, except as described below in relation to the valves V, V9. The fluid pressure in the opposite direction will act with the spring to keep the valve closed. However, each valve includes a mechanical active part which can open the valve in opposition to the forces of the spring and the pressure of the fluid. The valve shown by Figure 2 is representative of all of the valves V4, V5, V6, V7, V8, V9. Valves V4 and V9 further include a bypass passage which is always open and which is isolated from the valve plug. This passageway is not shown in Figure 2. Referring to Figure 2, the valve has a hole 122. A valve member 124 includes a valve plug 126 that is normally biased or tilted to a closed or seated position with respect to the orifice. 122 by a spring 128. The valve member 124 also includes an active portion 130 which projects outwardly from the valve housing 132. The passageway Pl leads in and out from the spring chamber 134. There is a chamber 136 of the valve on the opposite side of the orifice 122. A passageway P2 is connected to the chamber 136. The chamber 136 is also connected via the opening 138 to a passageway 140. When the passageway P2 is connected to the pressure and the passageway Pl is connected to the return path, a pressure difference acting on the plug 126 of the valve will move the plug 126 of the valve away from its seated position, against the force of the spring 128. This will open the orifice 122 and will allow the movement of the fluid pressure from the passageway P2, to the chamber 136, then through the hole 122, to the chamber 134 and to the passageway Pl. When the passageway Pl is connected to the pressure and the passageway P2 is connected to the return path, the plug 126 of the valve is normally biased or tilted towards its seated position by the combined forces of the spring 128 and the fluid pressure inside the valve. the chamber 134. However, a mechanical force applied longitudinally on the actuator 130, in opposition to the forces of the spring and of the fluid pressure, will unblock the cap 126 of the valve and allow the movement of the fluid pressure from the passageway Pl and the chamber 134 through the opening 122 towards the chamber 136 and the passages P2 and 140. As will be evident, the fluid pressure communicated with the chamber 136 through the passageway 140 will also unblock the cap 126 of the valve. The system shown in Figures 3-10 includes three linear hydraulic motors MI, M2, M3. The MI, M2, M3 engines are essentially similar to the engines described in U.S. Pat. No. 4,748,894 of the same applicant. The cylindrical portion of each motor MI, M2, M3 carries two axially spaced abutting or abutments A, which are arranged to couple the active parts of the valves V4-V9 to the mechanically opened valves V4-V9. The system also includes the elements DB1, DB2, DB3, which are transverse actuating beams connected to the motors MI, M2, M3, respectively, in the manner shown in U.S. Pat.

No. 4,793,469. Each transverse drive beam DB1, DB2, DB3 carries a plurality of connectors which are used to connect the drive beams DB1, DB2, DB3 to the conveyor slats. These connectors are shown in U.S. Pat. No. 4,793,469 and are designated as 82, 84, 86 in this patent. The construction of the drive beams DB1, DB2, and DB3 and the connectors are essentially the same as those described in U.S. Pat. No. 4,793,469. The description therein of these components is incorporated herein for reference. Referring to Figures 3-10, each MI, M2, M3 engine has four work chambers. These chambers are designated Cl, C2 (Figure 3), C3, C4 (Figure 4), C5, C6 (Figure 3), C7, C8 (Figure 4), C9, CIO (Figure 3) and Cll, C12 (Figure 4). The work chambers Cl, C2 are connected by a conduit 142 (Figure 3). The work chambers C3, C4 are connected by a conduit 144 (Figure 4). The work chambers C5, C6 are connected by a conduit 146 (Figure 3). The work chambers C7, C8 are connected by a conduit 148 (Figure 4). The work chambers C9, CIO are connected by a conduit 150 (Figure 3). The work chambers Cll, C12 are connected by a conduit 152 (Figure 4).

As shown in Figures 3-10, piston or piston rods include passages for fluid pressure, which provide fluid pressure in and out of work chambers C2, C3, C6, C7, and CIO , Cll. The passageway of the piston rod leading between the valve V9 and the working chamber C2 is designated as 154. The passageway leading between the valve V8 and the working chamber C3 is designated 156. The passageway leading between the valve V7 and the working chamber C6 is designated 158. The passageway leading between the valve V6 and the working chamber C7 is designated 160. The passageway leading between the valve V5 and the working chamber CIO is designated 162. The passageway leading between the valve V4 and the working chamber Cll is designated 164. Figures 3-10 illustrate a system including the passageways shown in Figure 1 and a number of additional passageways and associated valve openings. The passages 166 and 168 for the pressure lead to the valves V4, V9 as described further below. A bypass conduit 169 connects the conduit 120 with the opening 170 of the valve V3. The opening 172 of the valve V3 is connected by the conduits 174, 176 to the spring chamber of the valve V7 and by the conduits 174, 178 to the passageway 154 in the engine MI. The conduits 180, 192 connect the opening 182 of the valve V3 to the spring chamber of the valve V6. The conduit 180 and a conduit 184 connect the opening 182 of the valve V3 with the passageway 164 in the engine M3. A bypass conduit 186 connects the opening 188 in the valve V3 to the conduit 118. The conduit 190 connects the spring chamber of the valve V8 with the valve chamber, the valve V6 and the passage 160 in the engine M2. The conduit 194 connects the spring chamber of the valve V5 with the valve chamber, the valve V7 and the passage 158 in the engine M2. The pressure passage 166 leads directly from the pressure source to the spring chamber of the valve V4, and the pressure passage 168 leads directly from the pressure source to the spring chamber of the valve V9. Because of these connections, valves V4, V9 can only be opened mechanically. The pressure continuously supplied to the spring chambers through the passageways 166, 168, acts on the valve plugs to prevent them from being disengaged by the pressure in the valve chambers. The operation of the system is illustrated in Figures 3-10. Figures 3-6 illustrate the operation of the system for transporting a load in the discharge direction indicated by the arrow in Figures 3-6. Figures 7-10 illustrate the operation for transporting a load in the direction of the load indicated by the arrow in Figures 7-10. As noted above, the function of the V3 valve is to control the direction in which the system carries a load. Valve V3 has a first discharge position illustrated in Figures 3-6 and a second loading position illustrated in Figures 7-10. Referring to Figures 3-6, the valve V3 is positioned to block communication between the openings 170 and 182 and by means of which communication between the branch pipe 169 of the conduit 120 and the passageway 164 in the M3 engine is blocked. through the conduits 180, 184 and with the spring chamber of the valve V6 through the conduits 180, 192. The communication between the openings 188 and 172 of the valve V3 is open to allow communication between conduit 118, 186 and the spring chamber of the valve V7 by means of or through the conduits 174, 176 and with the passage 154 in the engine MI through the conduits 174, 178. In the position of load of the directional valve V3 shown in Figures 7-10, the communication between the openings 170, 182 is open and the communication between the openings 188, 172 is closed. Referring to Figure 3, at the start of the discharge cycle, the butt braces or unions A on the MI, M2, M3 engines are in contact with the active parts of the valves V8, V6, V4 and are holding the valves V8, V6, V4 in an open position. The switching valve 10 connects the conduit 120 to the pressure. The conduit 118 is connected to the tank or to the return path. The pressure in the conduit 120 is supplied to the working chamber C3 of the engine MI through the valve V8 and the passage 156 and to the working chamber C4 from the chamber C3 through the passageway 144. Inside the valve V8, the pressure acts on the valve plug and moves once the valve plug has been passed through the valve V8 to the conduit 190. From the conduit 190 it flows into the working chambers C7 and C8 of the valve. M2 motor by means of the valve V6 and the passages 160 and 148. While it is in the valve V6, the pressure acts on and moves once the valve plug has been passed, communicating the pressure to the passages 192, 184. This causes the pressure to be communicated to the working chambers Cll, C12 in the M3 motor through the bypass passage in the valve V4 and the passages 164, 152 of the motor. Accordingly, the work chambers C3, C4, C7, C8, Cll, C12, are fully connected to the pressure. At the same time, the work cameras Cl, C2, C5, C6, C9, CIO, are all connected to a return path. As a result, the cylinders of the three engines MI, M2, M3 move simultaneously in the discharge direction. The motors MI, M2, M3 simultaneously move the drive beams DB1, DB2, DB3, and the elements of the floor slats connected thereto, from the position shown in Figure 3 to the position shown in Figure 4. When the Engine cylinders begin to move, the abutments or butt joints A move out of contact with the active parts of the valves V4, V6, V8. The pressure in the valve chambers of the valves V6, V8 continues to keep the valves V6, V8 open so that the pressure continues to be supplied to the working chambers C7, C8 of the M2 motor and to the working chambers Cll , C12 of the M3 motor through the passageways 190 and 192, 184, respectively. The floor slats move in unison in the direction indicated by the "unload" arrow. If the conveyor device is inside a towing vehicle, the slats of the conveyor device are simultaneously moved from the front of the towing vehicle to the rear of the towing carriage, to discharge a load into the towing carriage. To facilitate the description of the operation of the system, here later the positions of the engine shown in Figures 3 and 4 will be referred to as the front and rear positions, respectively. With respect to the return connections shown in Figure 3, the working chamber Cl of the engine MI is connected to the working chamber C2 through the conduit 142. The working chambers Cl, C2 are connected to the conduit 178 through the passageway. 154 and the bypass passage in the V9 valve. The conduit 178 is connected to the conduit 174 which is connected to the return path through the valve V3 and the passages 186, 118. The working chamber C5 of the engine M2 is connected to the working chamber C6 through the passage 146 The working chambers C5, C6 are connected to the valve chamber, of the valve V7 through the passage 158. The spring chamber of the valve V7 is connected to the return path through the passages 176, 174. When the M2 motor starts to move, the return pressure in the working chambers C5, C6 and the passageway 158 causes the valve V7 to open instantaneously an amount sufficient to allow the fluid to escape from the working chambers C5, C6 through of the passage 158 and the open valve V7 to return through the conduits 176, 174. The working chamber C9 of the motor M3 is connected to the working chamber CIO through the conduit 150. The working chambers C5, C6 are connected the return path via the motor conduit 162, the valve chamber, the valve V5, and the conduit 118. When the movement begins and until near the end of the stroke, the valve V5 is and remains closed by its deviation or activation of the spring and by the return pressure in the conduit 194 which communicates to the spring chamber of the valve V5 with the valve chamber, of the valve V7. The valve V9 is similarly closed by its deflection or activation of the spring and by the communication of its spring chamber with the pressure through the conduit 168. Referring to Figure 4, when the motors MI, M2, M3 approach the its rear positions shown in Figure 4, the back abutments or abutments A on the engines MI, M2, M3 make contact with the operators of the valves V9, V7, V5, respectively. This moves the valves V5, V9 from their closed positions shown in Figure 3 to their open positions shown in Figure 4. This also fully opens the valve V7. The opening of the valve V9 communicates to the right-hand end (as shown) of the control rod 12 of the bypass or 3-way valve 10 to the pressure by means of the chamber 90 of the valve V2, the conduits 92 , 86, valve V9, and conduit 168, which is always connected to the pressure. The pressure from the conduit 86 is also communicated to the piston or piston 104 of the valve VI through the conduit 106. This causes the piston or piston 104 to move so that the rod 102 of the operator or of the active part extends to starting from it disengaging the ball 94. The left end of the control rod 12 is connected to the return path through the chamber 82 of the valve VI, the open orifice of the valve VI, the conduits 62, 58, 55 , the opening 50, and the conduit 53. The piston or piston 110 of the valve V2 is connected to the return path through the conduits 112, 84, the chamber 82 of the valve VI, etc. This allows the spring 100 to seat the ball 98. The pressure on the right-hand end of the control rod 12 moves the rod 12 to the left from the position shown in Figure 3 to the position shown in Figure 4. The The displacement of the bar 12 moves the passage 24 in the bar 12 out of communication with the return opening 56 and in communication with the opening 46 for distributing the pressure. At the opposite end of the bar 12, the passageway 26 is moved out of communication with the pressure distribution opening 48 and in communication with the return opening 66. This allows the pressure in the inlet opening 40 to move the element. of elevation 38 on the right (as shown). The lifting member 36 also moves to the right since the piston or piston at the left end of the lifting member 36 is exposed to the pressure through the opening 46 and has a surface area under pressure greater than the pressure. opposite end of the lifting element 36 which is exposed to the pressure in the inlet opening 40. The displacement of the lifting elements 36, 38 causes the conduit 118 to be diverted from the return path to the application of pressure through the opening 40, and the conduit 120 is to be derived from the application of the pressure to the return path through the opening. 52. The connection of the conduit 120 to the return path allows the deflection or inclination springs of the valves V6, V8 to close the valves V6, V8. The derivation of the conduits 118, 120 to the pressure and return application pathways, respectively, causes the motors MI, M2, M3 to move sequentially in the forward direction. The MI engine is the first to move. The pressure is communicated to the working chamber C2 of the engine MI through the passageway 154 of the engine, to the bypass passage through the valve V9, to the conduits 178, 174, to the valve V3, and to the conduits 186, 118 The pressure from the working chamber C2 is communicated to the working chamber Cl through the passage 142. The pressure in the working chambers Cl, C2 moves the motor forward from the rear position shown in the Figure 4 to the forward position shown in Figure 5. The movement of the motor is allowed by the connection of the working cameras C3, C4 to the return path. The camera C4 is connected to the camera C3 by the duct 144. The camera 3 is connected to the return path through the passageway 156 of the motor, the valve V8 and the duct 120. The movement of the MI motor out of its rear position shown in Figure 4, allows the deviation or actuation of the spring of the valve V9 to close the valve V9. When the MI motor moves to its forward or forward position shown in the Figure and until the MI motor is near the end of the travel, the valves V6, V8 at the front ends of the M2, MI motors remain closed under the force of their deflection or spring actuation. The valve V4 at the front end of the motor M3 remains closed under the force of its deflection or actuation of the spring and the connection of its spring chamber to the conduit 166, which is always connected to the pressure. The valve chamber of valve V4 is connected to the return path through conduits 78, 84 and chamber 82 of valve VI. The forward movement of the motor M2 is blocked by the blocking of the working chambers C7, C8 of the communication with the return path by the closed valve V8. Referring to Figure 5, when the MI engine approaches its front end to the travel position shown in Figure 5, the front stopper or attachment A on the MI motor engages the active part of the V8 valve to open the V8 valve. This communicates to the working chamber C7 of the M2 motor with the return path through the passage 160, the valve chamber, the valve V6, the passage 190, the open valve V8, and the conduit 120. The chamber of work C8 is also connected to the return path via conduit 146 and work chamber C7. The opening of the communication of the working cameras C7 and C8 with the return path, allows the motor M2 to be moved forward by the action of the pressure in the working chambers C5, C6 of the motor M2. The pressure is supplied through the conduit 118, the open valve V5, the conduit 194, the valve chamber, the valve V7, and the passageway 158. When the motor M2 moves to its forward or forward position shown in FIG. Figure 6, the forward movement of the M3 motor is blocked by the blocking of the working cameras Cll, C12 from the connection to the return path by the closed valve V6. The valve V6 remains closed until the motor M2 approaches the end of the forward or forward position of the path shown in Figure 6, when the support or front stop connection A on the motor M2 makes contact with the active part. of the V6 valve. The valve V7 closes as soon as the support or connection to the rear stop on the motor M2 moves out of contact with its active part due to its inclination or actuation by the spring. Referring to Figure 6, the opening of the valve V6 near the end of the travel of the motor M2 connects the working cameras Cll, C12 of the M3 motor to the return path. The chamber C12 is connected to the chamber Cll via the conduit 152. The chamber Cll is connected to the return path through the passageway 164, the bypass passage in the valve V4, the conduits 184, 192, the open valve V6, the conduit 190, the open valve V8, and the conduit 120. The opening of the working chambers Cll, C12 to the return path allows the pressure in the working chambers C9, CIO of the M3 motor to move the M3 motor from its rear position shown in Figure 6 to its forward position shown in Figure 3. The working chamber C9 is connected to the working chamber CIO by the duct 150. The working chamber CIO is connected to the pressure through the passage 162 , the valve chamber, the valve V5, and the conduit 118. When the back support or attachment A on the M3 motor moves out of contact with the active part of the V5 valve, the deviation or actuation of the spring of the valve V5 closes the valve V5. When the M3 motor approaches its front position shown in Figure 3, the front stopper or bracket A on the motor M3 makes contact with the active part of the valve V4 to open the valve V4. The opening of the valve V4 by the forward movement of the M3 motor causes the bypass valve to bypass or switch back to the position shown in Figure 3. The open valve V4 connects the left-hand end of the control rod 12 the bypass or three-way pressure valve connecting the pressure conduit 166 to the conduits 78, 84 and the chamber 82 of the valve VI. At the same time, the pressure is supplied to the piston or piston of the valve V2 through the conduits 78, 112. This causes the piston or piston 110 to move to dislodge the ball 98. The unsetting of the ball 98 connects the piston or plunger 104 of the valve VI to the return path, through the return passage 72, the chamber 90, and the conduits 92, 106, to allow the spring 96 to seat the ball 94. This also connects the end on the right side of the control bar 12 to the return path through the passageway 72 and the chamber 90. This allows the control rod 12 to move to the right from the position shown in Figure 6 to the position shown in FIG. Figure 3. The displacement of the bar 12 displaces the passageway 24 in the bar 12 again in communication with the return opening 56 and the passageway 26 again in communication with the pressure opening 48. The communication of the passageway 24 to the way of return allows the pressure in the opening 40 moves the lifting element 36 to the left from the position shown in Figure 6 to the position shown in Figure 3. The communication of the passage 26 to the pressure, allows the pressure to act on the end of the plunger of the lifting element 38 to move the lifting element to the left. The result is the return of all portions of the bypass or three-way valve 10 and of the safety valves VI, V2 to the configuration shown in Figure 3. The discharge cycle described above is then repeated with the first stage which is the movement of the totality of the three engines MI, M2, M3 simultaneously backwards. The charge cycle of the system is essentially the reverse of the discharge cycle described above. In the charge cycle, the three motors MI, M2, M3 move simultaneously in the forward direction and sequentially in the reverse direction. As noted above, the function of the V3 valve is to control the direction in which the system carries the load. In other words, the V3 valve controls whether the system operates in the charge or discharge cycle. The valve V3 is moved between its discharge position shown in Figures 3-6 and its loading position shown in Figures 7-10 at the start or start of the moving part or by the system operator. The movement of the valve V3 can be effected manually or by any other suitable means, such as by the provision of the valve V3 in the form of a solenoid valve.

Referring to Figure 7, at the beginning of the load cycle, the rear abutments or butts A on the MI, M2, M3 engines are in contact with the operators or active parts of the valves V9, V7, V5 and are maintaining to these open valves. The bypass or three-way valve 10 connects the conduit 118 to the pressure. The conduit 120 is connected to the return path. The pressure in the conduit 118 is supplied to the working chamber CIO of the engine M3 through the valve chamber, the valve V5 and the passage 162. The pressure in the working chamber CIO is communicated to the working chamber C9 through the conduit 150. The open valve V5 allows the supply of the pressure through the valve V5, the conduit 194, the valve chamber, the valve V7, and the passage 158, to the chamber C6 work of the M2 engine. The duct 146 communicates the pressure to the working chamber C5. The open valve 7 allows the pressure in the conduit 194 to be communicated through the valve V7, the conduits 176, 178, the bypass passage in the valve V9, and the passageway 154 in the engine MI, to the working chamber C2 of the MI engine. The conduit 142 communicates the pressure to the working chamber Cl. The connection of the working chambers Cl, C2, C5, C6, C9, CIO, to the pressure, causes the motors IM, M2, M3 to move simultaneously in the direction of loading or forward, indicated by the arrow in Figure 7. The movement is allowed by the connection of the working cameras C3, C4, C7, C8, Cll, C12 to the return path. The working chamber C4 of the engine MI is connected by means of the duct 144, the working chamber C3, the passageway 156, the valve chamber, of the valve V8, and the duct 120. The working chamber C12 of the M3 engine it is connected through the conduit 152, the working chamber Cll, the passageway 164, the bypass passage in the valve V4, the conduits 184, 180, the valve V3, and the conduit 120. The conduit 180 also communicates with the conduit 192 to connect the valve spring chamber V6 to the return path. In the M2 engine, the pressure in the working chambers C5, C6 that tends to move the M2 motor forward, creates the return pressure in the valve chamber, of the V6 valve, which opens the V6 valve in a enough to allow forward movement of the M2 engine. The sudden opening or rupture of the valve V6 connects the working chamber C8 to the return path through the conduit 148, the working chamber C7, the passage 160, the valve V6 from its valve chamber to its spring chamber once the plug of the unfastened valve has been passed, and the conduits 192, 180. The motors MI, M2, M3 move simultaneously forward from the position shown in Figure 7 to the position shown in FIG. Figure 8. At the start of the forward travel, the rear abutments or abutments A on the motors MI, M2, M3 move out of contact with the active parts of the valves V9, V7, V5. The pressure in the chambers of the valves V5, V7 continues to keep the valves V5, V7 open to continue supplying pressure for the forward movement of the MI, M2 motors. The front brackets or unions on the MI, M2, M3 engines couple the brackets or butt joints on the valves V8, V6, V4 when the MI, M2, M3 engines approach the end of their forward travel. The mechanical coupling opens the valves V4, V8 and opens the valve V6 completely. Referring to Figures 7 and 8, the opening of the valve V4 connects the left-hand end of the control rod 12 of the bypass or three-way valve to the pressure through the pressure line 166, the open valve V4 , the conduits 78, 84, and the chamber 82 of the valve VI. This also connects the piston or plunger 110 of the valve V2 to the pressure to cause the piston or plunger 110 to move and disengage the ball 98. This connects the right-hand end of the bar 12 and the piston or plunger 104 of the valve VI to the return path. The result is that the bar 12 moves to the right (as shown) and the lifting elements 36, 38 move to the left, as described above. This derives the pressure / return connections to the conduits 118, 120. The conduit 118 is diverted to the return path, and the conduit 120 is switched to the pressure. Referring to Figure 8, the change in the configurations of the bypass valve or three way 10 and the valves VI, V2 described above and illustrated in Figures 7 and 8, leads to the sequential movement of the MI, M2, M3 engines in the backward direction. The M3 engine is the first to move. The pressure for movement is supplied to the motor M3 from the conduit 120 through the valve 3, the conduits 180, 184, the bypass passage in the valve V4, and the passageway 164. This applies pressure to the working chambers Cll , C12 of the M3 engine. The working chambers C9, CIO are connected to the return path through the passageway 162, the valve chamber, the valve V5, and the conduit 118. The pressure is also supplied to the working chambers C3, C4 of the MI motor through the conduit 120 and the valve chamber, valve V8, and to the working chambers C7, C8 of the M2 motor through the open valve V8, the conduit 190, the valve chamber, of the valve V6, and the passage 160. The backward movement of the MI, M2 engines is blocked by blocking the other working chambers of these engines so that they return or connect to the return path until the M3 motor is near of the end of his journey. Referring to Figure 9, when the M3 engine is near the end of its travel backward, its rear stop connection A couples the active part of the valve V5 to open the valve V5. The opening of the valve V5 connects the working chambers C5, C6 of the M2 engine to the return path via the passageway 158, the valve chamber, the valve V7, the conduit 194, the open valve V5, and the conduit 118. This allows the motor M2 to move backward from its position shown in Figure 9 to its position shown in Figure 10. Referring to Figure 10, when the motor M2 approaches the end of its travel, its support or butt connection A rear makes contact with the active part of the valve V7 to open it. This opens the communication between the work chambers Cl, C2 of the engine MI and the return path through the passageway 154, the bypass passage of the valve V9, the conduits 178, 176, and the open valve V7. The resulting backward movement of the engine MI opens the valve V9 to thereby cause the bypass or three-way valve 10 and the valves VI, V2 to return to their configurations shown in Figure 7, as described above. with reference to Figures 3 and 4. Then the load cycle is repeated. Figure 11 shows three engines MI1, M2 ', M3' that can be used in place of the MI, M2, M3 engines in the system shown in Figures 3-10. The three engines MI ', M2', M3 'are essentially identical. Therefore, the following description of the engine MI 'applies also to the other two engines M2', M3 '. The motor MI 'comprises a cylinder 210 having opposed cylinder heads 212, 214 with axial openings through which a rod 216 of the piston or piston is received. A first end of the rod 216 of the piston or plunger has a ball 218 formed thereon, which is secured to a fixed support by means of a spherical block 220. The spherical block 220 can take various forms, such as those described in FIG. US patent No. 5,390,781, issued on February 21, 1995, and in copending application Serial No. 08 / 309,264, filed on September 20, 1994, both of the same applicant. The opposite closed end 222 of the stem 216 can also be secured to a fixed support. A head 224 of the piston or piston surrounds and is secured to a middle portion of the rod 216. The head 224 sealingly engages the inner circumferential surface of the cylinder 210 to mount the cylinder 210 for axial reciprocating movement relative to the piston rod or piston rod 216 . The head 224 of the piston or piston separates two annular working chambers C2 ', C3 '. The first working chamber C2 'is formed axially between the first head 212 of the cylinder and the head 224 of the piston or plunger. The second working chamber C3 'is formed axially between the head 224 of the piston or piston and the second head 214 of the cylinder. The fluid is introduced into and escapes or is released from the working chambers C2 ', C3' through the rod 216 of the hollow piston or piston. The interior of the rod 216 is divided by a tube 226 in an annular passage 154 'and a central passage 156'. An end seal 228 seals the outer end of the tube 226 to prevent communication between the two passages 154 ', 156' of the rod. One or more openings 230 are formed in the side wall of the rod or rod 216 to communicate the annular passage 154 'with the working chamber C2'. Axially outward of the end seal 228, another opening or set of openings 232 communicates to the passage 156 'of the central rod or rod with the working chamber C3'. The introduction of the fluid pressure in the working chamber C3 'and connecting the working chamber C2' to the return path, causes the cylinder 210 to move in the discharge direction, indicated by the arrow in Figure 11. The introduction of the pressure in the working chamber C2 'and connecting the chamber C3' to the return path causes the movement of the cylinder 210 in the opposite direction. Each of the three engines MI ', M.2', M3 'has attached thereto a transverse driving beam DB1', DB2 ', DB3', respectively. Each of the driving beams DB1 ', DB2', DB3 'is connected to the cylinder 210 of its respective motor and to the floor slats in the corresponding set of the floor slats. The operation of the motors MI ', M2', M3 'is substantially the same as the operation of the MI, M2, M3 motors shown in Figures 3-10. The operation is controlled by the check valves V4 ', V5', V6 ', V7', V8 ', V9' which are associated with the engines MI ', M2', M3 'and operate in the same way as the valves V4 , V5, V6, V7, V8, V9 shown in Figures 3-10. The valves V4'-V9 'and the motors MI', M2 ', M3' are connected to the pressure and the return path through the ducts corresponding to the ducts shown in Figures 3-10 and which have the same Numerical references in Figure 11. The portions of the engines MI ', M2', M3 'corresponding to the portions of the engines MI, M2, M3 shown in Figures 3-10, are indicated in Figure 11 by the same numerical reference with a designation of an apostrophe added to them. The cylinder 210 of each motor MI ', M2', M3 'carries a pair of abutments or abutments A', A '' to mechanically open the valves V4'-V9 '. Since both valves associated with a particular motor are located on the same end of the motor, the second stop or butt joint A "is axially spaced from the cylinder 210 which carries it. The abutment or abutment A "engages the end remote from the valve to open the valve. The valves communicate to the working chambers of the engine with the pressure and the return path through the passageways in the spherical blocks 220 and the corresponding passages in the spherical ends 218 of the piston rod or plunger. These passageways in turn communicate with the passages of the rod of the piston or piston, the passages 154 ', 156' in the case of the engine MI '. As in Figures 3-10, the engines MI ', M2', M3 'shown in Figure 11 are incorporated in a system which also includes a switching valve 10 and a valve V3 for steering control (not shown in FIG. Figure 11). Figure 12 is a longitudinal sectional view of another embodiment of the bypass or three-way valve of the invention. In Figure 12, the three-way or three-way valve elements 10 'which are similar to the elements of the valve 10 shown in Figure 1, have the same reference numbers as in Figure 1. The elements that are corresponding but that are modified, have the same numerical reference with the addition of an apostrophe or virgulilla designation. The elements that are part of the non-corresponding structure have unique numerical references. Referring to Figure 12, the three-way or bypass valve 10 'has a three-part housing that includes the opposite end portions 18', 20 ', and a central portion 22' of the housing positioned therebetween. The ends of a longitudinal cavity extending through the parts 18 ', 20', 22 'of the housing are closed by the end plugs 14', 16 'of the housing. The control rod 12 of the valve is received in the cavity. The lifting elements 36, 38 are placed on and supported by the control rod 12. As in the valve 10 shown in Figure 1, the longitudinal movement of the control rod 12 causes the movement of the lifting elements 36, 38. to alternatively connect the outlet openings 114, 116 to the pressure and return path. The return openings 50 ', 52' to which the outlet openings 114, 116 are connected, which are for connecting the openings 114, 116 to the return path, are modified because, instead of being separate openings, the opening 52 'is an internal opening connected to opening 50' by a passageway 262. This modification has no effect on the functioning of the valve. The main differences between the valve 10 'shown in Figure 12 and the valve 10 shown in Figure 1, are in the structure of the pressurized passages and in the safety valves associated with the pilot chambers 74, 76 of the bar control 12. The pressure passages 242, 248, extend from the openings 46 ', 48' for the distribution of the pressure, respectively. The bypass passages 242, 248 connect the openings 46 ', 48' to the additional openings 244, 250 for pressure distribution. A restriction 246, 252 is formed in each of the openings 244, 250. The openings 244, 250 open on the pilot chambers 74, 76, by means of which the pilot chambers 74, 76 are connected continuously to the Pressure. Restrictions 246, 252 prevent undesirable displacement of control rod 12 in response to a leak in the system. As noted above, each pilot camera 74, 76 is continuously connected to the pressure. The relief of the pressure in the pilot chamber 74, 76 is normally blocked by a safety valve VI ', V2'. The valve VI 'associated with the pilot chamber 74 has a closing ball 94 and a bypass spring 96 in a chamber 254 of the valve. The spring 96 normally deflects or tilts the ball 94 to close a hole separating the chamber 254 from the valve, from the pilot chamber 74. A conduit 256 is in open communication with the chamber 254 of the valve. The valve V2 'associated with the pilot chamber 76 has the same structure. A closure ball 98 located in the chamber 258 of the valve is biased or biased by a spring 100 to close a hole separating the chamber 258 from the valve and the pilot chamber 76. A conduit 260 is in open communication with the chamber. 258 of the valve. In the operation of the valve 10 ', the connection of the conduit 260 to the return path allows the control rod 12 to move from the position shown in Figure 12 to the right (as shown). The displacement of the control rod 12 causes the lifting elements 36, 38 to move, as described above. The connection of the duct 260 to the return path allows the pressure in the pilot chamber 76 to disengage the closing ball 98 and by means of this the pilot camera 76 is connected to the return path. When the pilot chamber 76 is connected to the return path, the pressure moves out of the pilot chamber 76 through the faster valve V2 'of which can be moved in the pilot chamber 76 through the restriction 252 to create the difference of the pressures that allows the control rod to move 12. The displacement of the control rod in the other direction (to the left as shown) is effected by connecting conduit 256 to the return path to allow pressure in pilot chamber 74 to disengage seal ball 94 and thereby connect pilot chamber 74 to the return path. Although the preferred embodiments of the invention have been illustrated and described here, it is proposed to be understood by those skilled in the art that modifications and omissions may be made in form and detail, without departing from the spirit and scope of the invention as defined by the following claims.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates.

Having described the invention as above, property is claimed as contained in the following

Claims (12)

R E I V I N D I C A C I O N S

1. In an improved bypass or three-way valve, of a type having a two-position control rod with a pilot camera at each of its ends, the improvement is characterized in that it comprises: for each of the pilot cameras: first passage connected to the pressure line and communicating with the pilot camera; a second passage separated from the first passageway and connectable to the return path; and a safety valve having a valve element biased or biased towards a closed position in which it closes a hole to interrupt or close the communication between the pilot chamber and the second passageway; the valve element has an open position in which it is moved away from the orifice, to open the hole and connect the pilot chamber to the return path through the second passage, to allow the displacement of the control rod; the first passage communicates with the pilot chamber when the valve element is in the closed position or in the open position.

2. The improvement according to claim 1, characterized in that, during use, the pilot chamber is in continuous communication with the pressure through the first passageway, and the valve element is moved to its open position by the pressure in response to the connection of the second passage to the return path.

3. The improvement in accordance with claim 2, characterized in that it comprises a restriction in the first passage to allow the pressure to move out of the pilot chamber through the orifice faster than the pressure can move towards the pilot chamber through the first catwalk

4. The improvement according to claim 1, characterized in that it comprises an active part placed to couple the valve element; and in which the second passageway is, during use, continuously in communication with the return path, and the valve element is moved mechanically to its open position by the active part in response to the pressure acting on the valve. the active part.

In an improved, three-way bypass valve of a type having a two-position control rod with a pilot chamber at each of its ends, the improvement is characterized in that it comprises: for each of the pilot cameras: a first passage that can be connected to the pressure and communicates with the pilot camera; a second passage connected to the return path; a safety valve that includes a deflected or inclined valve element for closing a hole, for interrupting or closing the communication between the second passage and the pilot chamber, and an operator having a first end positioned to engage the valve element and a second end with a piston or piston formed thereon; and a conduit communicating with the first passageway for the pilot chamber with the piston or plunger of the safety valve for the other pilot chamber; wherein the pressure in the first passageway for one of the pilot chambers is communicated to the first of the pilot chambers and to the piston or plunger of the safety valve for the other of the pilot chambers, to move the piston or piston and mechanically disengage to the valve element to connect the other of the pilot chambers to the return path and allow the pressure in one of the pilot chambers to move the control rod.

6. In combination, the improvement according to claim 5; and a plurality of drive motors, each of the motors has a movable portion carrying a stop or butt joint; and first and second check valve, one for each of the first passages; each of the check valves has a valve element biased or tilted towards a closed position in which it blocks the first corresponding passageway, and an active part placed so that it is coupled by one of the butt supports or joints, for mechanically disengage the valve element from the check valve and connect the first passage corresponding to the pressure.

7. In combination: the improvement in accordance with the claim 5; and a plurality of drive motors, each motor having a movable portion carrying a stop or butt joint; and first and second check valves, one for each of the first passages; each of the check valves has a valve element biased or tilted towards a closed position in which it blocks the first corresponding passageway, and an active part placed so that it is coupled by one of the butt supports or unions to unseat mechanically to the valve element of the check valve and to connect the first passage corresponding to the pressure; characterized in that the three-way valve operates to bypass the ways of applying pressure and return between the first and second supply conduits, leading to the motors causing the movable portions to move in an alternative manner.

8. The combination according to claim 6 or claim 7, characterized in that, during use, each of the check valves is continuously connected to the pressure acting on the valve element, of the check valve, to divert or tilt the valve element, from the check valve, to the closed position.

9. In an improved three-way bypass valve of a type having a return opening and a two position control rod with a pilot chamber at each of its ends, the improvement is characterized in that it comprises: security for each of the pilot cameras; each of the safety valves has a valve cavity divided by a hole in the first and second valve chambers, which communicate with the pilot chamber and the return opening, respectively, a valve element in the first chamber of the valve. valve, deflected or inclined to close the orifice, a piston or piston slidably received in the valve cavity spaced from the orifice, to partially define the second chamber of the valve, and a stem of the active part or for the operator that is extends from a first end of the piston or plunger into the second valve chamber and orifice, to engage and disengage the valve member in response to movement of the piston or plunger toward the orifice; and a conduit communicating to the first valve chamber of each of the safety valves with a second opposite end of the piston or piston of the other safety valve; wherein the pressure communicated to one of the pilot chambers through the first valve chamber of the respective safety valve, is also communicated to the second end of the piston or piston of the other safety valve, to disentangle the element from the valve of the other safety valve and by means of this connect the other pilot chamber to the return path and allow the pressure in the first of the pilot cameras to move the control rod.

10. In combination: the improvement according to claim 9; and a pressure line for each of the first valve chambers connecting the first valve chamber to the pressure; and a plurality of drive motors, each of the motors has a movable portion carrying a stop or butt joint; and first and second check valves, one for each of the pressure lines; each of the check valves has a valve element biased or tilted towards a closed position in which it blocks the pressure line, and an operator placed to be coupled by one of the butt supports or joints, to unseat mechanically to the valve element, of the check valve and connect the first chamber of the valve corresponding to the pressure

11. In combination: the improvement according to claim 9; and a pressure line for each of the first valve chambers, which connects the first chamber of the valve to the pressure; and a plurality of drive motors, each of the motors has a movable portion carrying a stop or butt joint; and first and second check valves, one for each of the pressure lines; each of the check valves has a valve element biased or tilted towards a closed position in which it blocks the pressure line, and an operator placed to be coupled by one of the butt supports or joints, to unseat mechanically to the element of the valve, of the check valve and connect the first chamber of the valve corresponding to the pressure; characterized in that the bypass or three-way valve operates to bypass the pressure and return paths between the first and second supply conduits leading to the motors, to cause the movable portions to move in an alternating manner.

12. The combination according to claim 10 or claim 11, characterized in that, during use, the check valve is connected continuously to the pressure acting on the valve element, of the check valve, to deflect or tilt to the valve element, from the check valve, to the closed position. SUMMARY OF THE INVENTION The present invention relates to a three-way bypass valve having a control bar with a pilot chamber at each of its ends. For each pilot camera, there is a first passage connected to the pressure line and communicating with the pilot camera. A second passage can be connected to the return path. A safety valve has a valve element biased or tilted to close a hole to interrupt or close communication between the pilot chamber and the second passageway. The valve element has an open position in which the pilot chamber is connected to the return path by means of the second passageway, to allow displacement of the control rod. In a first embodiment, the pilot chamber is continuously in communication with the pressure through the first passage, and the valve element is opened by this pressure in response to the connection of the second passage to the return path. In another embodiment, the second passageway is in continuous communication with the return path, and the valve member is moved mechanically to its open position by an operator or active part in response to the pressure acting on the active part. A four-way directional control valve controls the bypass lines that lead from the bypass or three-way valve to the drive motors.