JPH0226116B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an oil passage switching valve used in a hydraulic circuit.

[Prior Art] An oil passage switching valve includes a spool that is movably disposed within a casing and forms an oil chamber between the spool and the casing, and a means for biasing the spool in one direction. By selectively supplying and discharging hydraulic pressure to the oil chamber, the spool is selectively moved to one end and the other end of the casing, and the positions of the land formed on the spool and the plurality of oil ports formed on the casing are determined. There are so-called two-position switching valves that switch communication between oil ports by changing the relationship.

Such two-position switching valves can be assembled into the casing from one direction, as all the lands on the spool need to be made to have the same diameter, or only one end needs to be made to have a large diameter, making it easy to layout the valve inside the casing. It is easy to assemble,
For example, it is widely used when a plurality of valves are disposed within a casing, such as in a hydraulic control device for an automatic transmission.

However, in a 2-position switching valve like the one above, 1
Only two communication patterns can be set for one valve, which tends to complicate the oil passage and increase the number of valves.

In addition, the spool is held at an intermediate position by springs disposed at both ends of the spool, and
A three-position switching valve has also been proposed in which the communication state can be set in three patterns using one valve. However, in this structure in which the spool is held at an intermediate position by the springs at both ends of the spool, the intermediate stop position of the spool fluctuates due to variations in the loads generated by the springs at both ends. For this,
It has also been proposed to arrange flange members at both ends of the spool so that the flange members abut against the end wall of the casing when the spool is in the intermediate position, thereby stably holding the spool in the intermediate position. .

[Problems to be Solved by the Invention] However, since the flange members disposed at both ends of the spool have a larger diameter than the land that switches the communication of the oil port of the spool in order to contact the casing, the assembly work is difficult. Assembly is complicated as it has to be done from two directions, and the casing has to be divided into parts in order to install a member with a larger diameter than the land that switches the communication of the oil port at both ends of the spool. When a plurality of valves are disposed within a casing, such as in a hydraulic control device for a transmission, the location for disposing them is limited, and the layout of the valves cannot be easily arranged.

The present invention makes it possible to stop the spool at both ends within the casing, as well as to stop the spool at an intermediate position, making it possible to switch connections between three types of oil ports, and at least one end of the spool can be stopped at both ends of the spool. The purpose of the present invention is to provide an oil passage switching valve that can be configured to have a diameter smaller than the diameter of a land that switches communication between oil ports and has excellent assemblability.

[Means for solving the problem] The oil passage switching valve of the present invention has a plurality of oil ports 7,
8 and 9, and a plurality of lands 11, 12, 15, and 16, which are movably arranged in the casing and connect the oil ports of the casing to other plurality of lands. A spool 1 selectively communicates with an oil port and forming first and second oil chambers 31, 41 facing each other between the spool 1 and the casing; the casing has a first hydraulic pressure supply port 3 communicating with the first oil chamber, and a biasing means 2 for moving the casing to the second oil chamber.
The land has a second hydraulic pressure supply port 4 communicating with the oil chamber, an oil drain port 6, and an orifice 13 provided in an oil passage that supplies hydraulic pressure to the first hydraulic pressure supply port, and the land has: A first pressure receiving surface 111 where the hydraulic pressure supplied to the first oil chamber acts to bias the spool in one direction, and a first pressure receiving surface 111 where the hydraulic pressure supplied to the second oil chamber acts to bias the spool. a second pressure-receiving surface 121 that biases the spool to the other position and moves the spool to the other position against the biasing means;
The first oil chamber is provided at a position that blocks communication between the oil chamber and the oil drain port and allows the first oil chamber to communicate with the oil drain port when the first oil chamber is in an intermediate position between the one position and the other position. It is characterized by

[Operation and effects of the present invention] The oil passage switching valve of the present invention exhausts pressure from the first oil chamber 31 through the first oil pressure supply port 3, and exhausts pressure from the second oil chamber 41 through the second oil pressure supply port 4. A biasing means 2 that acts on the spool by selectively supplying and discharging hydraulic pressure to the spool.
The urging force applied to one side by the spool 1 and the hydraulic pressure supplied to the second oil chamber
1 to selectively move the spool 1 between one position and the other position at both ends of the casing A to connect the two types of oil passages. can be switched.

Furthermore, when oil pressure is supplied to the first oil chamber 31 while the second oil chamber 41 is being supplied with oil pressure, the first oil chamber 41 is supplied with oil pressure.
The force that biases the spool 1 in one direction is generated when the hydraulic pressure acting on the oil chamber 31 of the land 11 acts on the first pressure receiving surface 111 of the land 11, and the force that biases the spool 1 in one direction by the biasing means 2. The resultant force is generated by the hydraulic pressure acting on the second oil chamber 41 acting on the second pressure receiving surface 121 of the land 12 on the spool 1.
The spool 1 moves from the other position to the one position by overcoming the force urging the other side.

In the present invention, the land 11 has a structure that is provided at a position that allows the first oil chamber 31 to communicate with the oil drain port 6 when the spool 1 is in an intermediate position between one position and the other position. Therefore, when the spool 1 moves from the other position to an intermediate position between the other position and one position, the first oil chamber 3
1 is communicated with the oil drain port 6, and oil begins to flow from the first oil chamber 31 to the oil drain port 6, and the amount of oil flowing out increases as the spool 1 moves from the intermediate position to one position.

On the other hand, since the casing A has an orifice 13 provided in an oil passage that supplies oil pressure to the first oil pressure supply port 3 that communicates with the first oil chamber 31,
The flow rate of oil supplied from the hydraulic pressure supply port 3 to the first oil chamber 31 is restricted by an orifice 13.

Therefore, when the spool 1 is in the intermediate position, the oil pressure in the first oil chamber 31 is regulated by the balance between the inflow amount supplied via the orifice 13 and the outflow amount to the oil drain port 6. The regulated hydraulic pressure acting on the oil chamber 31 of the first pressure receiving surface 11 of the land 11
The resultant force of the force that biases the spool 1 in one direction caused by the force acting on the second oil chamber 41 and the force that biases the spool 1 in one direction by the biasing means 3 causes the hydraulic pressure that acts on the second oil chamber 41 to be applied to the land 12. The force that urges the spool 1 toward the other side is balanced by the force acting on the second pressure receiving surface 121, and the spool 1 stops at the intermediate position.

Therefore, it is possible to stop the spool 1 not only at both ends within the casing A but also at an intermediate position,
The communication of the oil port can be set not only at both ends of the casing but also at an intermediate position, and the communication state can be set in three patterns with one valve, which is effective in simplifying the oil passage and reducing the number of valves.

Furthermore, when the spool 1 is stopped at an intermediate position, the regulated hydraulic pressure acting on the first oil chamber 31 is transferred to the land 11.
The resultant force of the force that biases the spool 1 in one direction generated by acting on the first pressure receiving surface 111 of the force and the force that biases the spool 1 in one direction by the biasing means 2 is
This is achieved by balancing the force that urges the spool 1 toward the other side due to the hydraulic pressure acting on the second oil chamber 41 acting on the second pressure-receiving surface 121 of the land 12, thereby regulating the movement of the spool 1. The spool 1 can be reliably stopped at an intermediate position without providing any member to stop the first pressure receiving surface 111.
The land 11 of the spool 1 on which the oil passage switching valve is provided can be configured to have a diameter smaller than the diameter of the lands 15 and 16 that switch communication between the oil ports of the spool 1, and the oil passage switching valve is easy to assemble.

[Example] The present invention will be explained based on embodiments shown in the drawings.

1 to 3 show a first embodiment of the present invention, where A is a casing and 1 is a valve spool movably disposed within the casing A. The valve spool 1 has lands 11 and 12 at both ends and lands 15 and 16 arranged between these lands, and oil chambers facing each other are provided between the casing A and the left end land 11 in the drawing and the right end land 12 in the drawing, respectively. 31 and 41 are configured. A spring 2 is disposed within the oil chamber 31, and the valve spool 1 is biased to the right in the figure by the spring load of the spring 2. Casing A has an oil chamber 31 at the left end in the diagram.
A first hydraulic pressure supply port 3 connected to the oil chamber and a second hydraulic pressure supply port 4 connected to the oil chamber at the right end in the figure are formed, and the hydraulic pressures supplied from these supply ports 3 and 4 to the oil chambers 31 and 41, respectively, are as follows. It acts on the pressure receiving surface 111 (pressure receiving area A11) of the land 11 at the left end in the figure and the pressure receiving surface 121 (pressure receiving area A12) at the right end land 12 in the figure. Also, in the casing A, from the left side of the figure, there is an oil port 5,
An oil drain port 6, an oil port 7, an oil port 8, and an oil port 9 are formed, and in this embodiment, the oil port 5 is composed of oil ports 51 and 52 that communicate with each other. Reference numeral 13 denotes an orifice that is provided in an oil passage 14 that communicates with the oil pressure supply port 3 and supplies pressure oil, and controls the flow rate of oil pressure that is supplied to the oil chamber 31.

This oil path switching valve is operated by supplying oil pressure to the oil chamber 41 from the second oil pressure supply port 4 to the valve spool 1.
Hydraulic pressure P1 is applied to the pressure receiving surface 121 of the right end land 12 in the diagram.
2 is applied, and the oil chamber 3 is supplied from the first oil pressure supply port 3.
When hydraulic pressure is not supplied to the first valve spool 1, the spring load Fs by the spring 2 and the biasing force by the hydraulic pressure P12 applied to the pressure receiving surface 121 of the land 12 have a relationship of Fs<P12×A12, and the valve spool 1 is connected to the first valve spool 1. As shown in the figure, it is moved to the left in the figure and fixed. As a result, the oil port 52 and the oil drain port 6 are connected via the land 11 and the land 15, and the oil port 7 and the oil port 8 are communicated via the land 15 and the land 16. In addition, the lands 11, 15, and 16 provide a connection between the first oil pressure supply port 3 and the oil port 51, between the oil drain port 6 and the oil port 7, and between the oil port 8 and the oil port 9. The contact is broken and a first contact pattern is obtained. Hydraulic pressure is supplied to and discharged from the first and second oil pressure supply ports 3 and 4 by, for example, an electromagnetic solenoid valve installed in the oil passage.

When pressure is exhausted from both the first and second hydraulic supply ports 3 and 4, the spring load Fs by the spring 2 causes pressure to be discharged from the second hydraulic pressure supply port 4, and hydraulic pressure is discharged from the first hydraulic pressure supply port 3. When the valve spool 1 is being supplied, the spring load Fs from the spring 2 and the urging force from the hydraulic pressure P11 acting on the pressure receiving surface 111 of the land 11 move the valve spool 1 to the right in the figure and fix it, as shown in FIG. As a result, the first oil pressure supply port 3 and the oil port 51, which had been blocked by the land 11, are connected, and the oil drain port 6 and the oil port 7 are connected via the land 11 and the land 15. The oil ports 8 and 9 are connected via the lands 15 and 16, and the oil ports 52 and 6 are connected by the lands 11 and 15. The communication between 7 and oil port 8 is cut off, resulting in a second communication pattern.

When hydraulic pressure is supplied to the oil passage 14 while the valve spool 1 is set to the left in the figure as shown in FIG. The resultant force with the spring load Fs is the pressure receiving surface 1 of the land 12.
The valve spool 1 overcomes the biasing force due to the hydraulic pressure P12 acting on the valve spool 21, and the relationship Fs+P11×A11>P12×A12 is established, so the valve spool 1 begins to move toward the right in the figure. However, when the valve spool 1 reaches the intermediate position shown in FIG. The oil port 52 and the oil drain port 6 are in communication between the right end of the land 11 in the drawing and the right end of the second oil port 52 in the drawing through C2. Therefore, the hydraulic pressure supplied from the first hydraulic pressure supply port 3 via the orifice 13 is
1. Oil ports 51, 52, between C2, oil drain port 6
The oil pressure inside the oil chamber 31 decreases because more oil is discharged. As a result, the valve spool 1 receives the spring load Fs from the spring 2 and the hydraulic pressure P11 supplied from the first hydraulic pressure supply port 3 via the orifice 13.
The oil pressure P11' is regulated and decreased by flowing out through the third oil port 6 between C1 and C2.
is applied to the pressure-receiving surface 111 of the land 11, and the hydraulic pressure P is applied to the pressure-receiving surface 121 of the land 12.
12 is balanced, and the relationship is Fs+P11'×A11=P12×A12, so it stops at the intermediate setting position shown in FIG. The amount of pressure oil passing through C2 must be set to be sufficiently larger than the amount of oil passing through C1 in order to stably stop the spool 1 at the set position and maintain the oil port 5 in a discharged pressure state. Therefore, there is a relationship between C2 and C1. As a result, when the valve spool 1 is set to the right side in the figure or the left side in the figure, the communication between the oil ports 8 and 9, or the communication between the oil ports 7 and 8, is maintained by the land 15, 16, and the communication state between the oil port 5 and the oil drain port 6 is maintained even when the valve spool 1 is stopped at the intermediate setting position, and a third oil passage communication pattern is obtained. Next, when the oil pressure in the oil passage communicating with the second oil pressure supply port 4 is discharged, the valve spool 1 is fixed to the right side in FIG. 2. Even if oil pressure is supplied to the second oil pressure supply port 4 again in this state, the oil drain port 6 is blocked by the land 11, so the urging force due to the oil pressure P11 acting on the pressure receiving surface 111 of the land 11 and the spring 2 The resultant force with the spring load Fs overcomes the biasing force due to the hydraulic pressure P12 acting on the pressure receiving surface 121 of the land 12, resulting in the relationship Fs+P11×A11>P12×A12, and the valve spool 1 does not move.

FIG. 4 shows a second embodiment of the invention. In this embodiment, the oil port 5 has a width L1 equal to both ends of the oil port 51 and the oil port 52 in the first embodiment, and the land 1
For the width L2 of 1, the relationship is L1=L2+C1+C2. Furthermore, since the positions of the lands 15 and 16 are different from those in the first embodiment, the connection pattern is as follows.

When the valve spool 1 moves to the left in the figure and is fixed, the oil port 5 and the oil drain port 6 are in communication, and the oil port 7 and the oil port 8 are in communication via the land 15 and the land 16. At the same time, communication between the first hydraulic pressure supply port 3 and the oil port 5 is cut off by the land 11, and communication between the oil drain port 6 and the oil port 7 is cut off by the land 1.
5 and the oil port 9 is closed by a land 16.

When the valve spool 1 moves to the right in the drawing and is fixed, the first oil pressure supply port 3 and the oil port 5 are connected, and the oil drain port 6 and the oil port 7 are connected through the land 11 and the land 15. Contacted and Land 1
5 and the land 16 between the oil port 8 and the oil port 9.
At the same time, the communication between the oil port 5 and the oil drain port 6 is cut off by the land 11, and the communication between the oil port 7 and the oil drain port 8 is cut off by the land 11.
Communication with land 15 is cut off by land 15.

When the valve spool 1 is stopped at the intermediate position, the oil port 8 communicates with both the oil port 7 and the oil port 9 via the land 15 and the land 16.

FIG. 5 shows a third embodiment of the invention. In this embodiment, the land 12 is formed to have a larger outer diameter than the land 11, and instead of the spring in the above embodiment, an oil chamber 211 is formed between the casing A and the valve spool 1, and is connected to the oil chamber 211. When hydraulic pressure is supplied from the third hydraulic pressure supply port 21, the hydraulic pressure acts on the third pressure receiving surface 122 corresponding to the difference in pressure receiving area between the land 11 and the land 12, and urges the valve spool 1 to the right in the figure. do. Further, in this embodiment, the lands 11 are formed apart from each other in the axial direction.
The hydraulic pressure supplied from the second hydraulic pressure supply port 4 is set lower than the hydraulic pressure supplied from the first hydraulic pressure supply port 3 and the third hydraulic pressure supply port 21.

First hydraulic pressure supply port 3 or third hydraulic pressure supply port 2
When hydraulic pressure is supplied to the hydraulic pressure supply port 1 and the second hydraulic pressure supply port 4 is discharged, the valve spool 1 is set to the right in the figure, and the first, second and third hydraulic pressure supply ports 3, 4, and When hydraulic pressure is supplied to all of the valve spools 21, the valve spool 1 is set to the right in the drawing. When hydraulic pressure is supplied only to the second hydraulic pressure supply port 4, the valve spool 1 is set to the left in the drawing. When hydraulic pressure is supplied to the hydraulic pressure supply port 3 from the state where the valve spool 1 is set to the left in the figure, the valve spool 1 moves to the right in the figure and reaches the fifth position.
At the intermediate position shown in the figure, a part of the hydraulic pressure supplied from the first hydraulic pressure supply port 3 leaks from C1 between the illustrated left end of the land 11A and the illustrated left end of the first oil port 51, and the valve spool The hydraulic pressure supplied from the hydraulic pressure supply port 3 and a part of which leaks from the above-mentioned C1 and the third
Due to the balance between the hydraulic pressure supplied from the hydraulic port 21 and the hydraulic pressure supplied from the second hydraulic pressure supply port 4, it is stopped at the intermediate position. Note that in this embodiment, the first hydraulic pressure supply port 3 and the third hydraulic pressure supply port 21
The sum of the pressure receiving area of the hydraulic pressure applied from the second hydraulic pressure supply port 4 and the pressure receiving area of the hydraulic pressure supplied from the second hydraulic pressure supply port 4 are made equal, and the magnitude of the second hydraulic pressure supplied from the second hydraulic pressure supply port 4 is made equal. By setting the first and third hydraulic pressures to be smaller than the first and third hydraulic pressures supplied from the first and third hydraulic supply ports 3 and 21, when hydraulic pressure is supplied from all the hydraulic pressure supply ports, the spool 1 is moved toward the right side in the figure. However, the hydraulic pressures supplied from the first, second and third hydraulic pressure supply ports are made equal, and the first hydraulic pressure supply port 3 and the third hydraulic pressure supply are set to be equal as shown in FIG. A similar effect can be achieved by making the sum of the pressure receiving areas of the hydraulic pressure supplied from the port 21 larger than the pressure receiving area of the hydraulic pressure supplied from the second hydraulic pressure supply port 4.

[Brief explanation of drawings]

1, 2, and 3 are sectional views of a valve according to one embodiment of the present invention, and FIG. 4 is a sectional view of a second embodiment. FIG. 5 is a sectional view of the third embodiment;
FIG. 6 is a sectional view of the fourth embodiment. In the figure, A...casing, 1...valve spool, 2...spring, 3...first hydraulic supply port, 4...second hydraulic supply port, 5, 7, 8, 9...
...Oil port, 6...Oil drain port, 11, 12, 15, 16
...Land, 13...Orifice, 21...3rd
Hydraulic pressure supply port, 31...first oil chamber, 41...second oil chamber, 211...third oil chamber, 111...first pressure receiving surface, 121...second pressure receiving surface, 122...
...Third pressure receiving surface.

Claims (1)

[Claims] 1. A casing provided with a plurality of oil ports, and a plurality of lands, which are movably disposed within the casing, and the lands connect the oil ports of the casing to other plurality of oil ports. a spool that selectively communicates with the oil port and forms first and second oil chambers facing each other between the spool and the casing; and a spool that is biased in one direction to move the spool to one position. The casing includes a first hydraulic supply port communicating with the first oil chamber, a second hydraulic supply port communicating with the second oil chamber, and an oil drain port. an orifice provided in an oil passage that supplies oil pressure to the first oil pressure supply port, and the land is configured such that the oil pressure supplied to the first oil chamber acts to attach the spool to the one side. The first pressure-receiving surface that is biased and the hydraulic pressure supplied to the second oil chamber act to bias the spool in the other direction, and move the spool to the other position against the biasing means. and a second pressure-receiving surface, which blocks communication between the first oil chamber and the oil drain port when the spool is in the other position, and has a second pressure-receiving surface. An oil passage switching valve characterized in that the oil passage switching valve is provided at a position that allows the first oil chamber to communicate with the oil drain port when the valve is in an intermediate position. 2. The oil path switching valve according to claim 1, wherein the means for biasing the spool in one direction is a spring that applies a spring load to the spool from one side. 3. The means for biasing the spool in one direction includes a third oil chamber formed between the spool and the casing, and a means provided in the casing to supply hydraulic pressure to the third oil chamber. The spool is characterized by comprising a third hydraulic pressure supply port and a third pressure receiving surface formed on the spool so that the hydraulic pressure supplied to the third oil chamber urges the spool in the one direction. An oil passage switching valve according to claim 1. 4. The casing has an oil port disposed between the first oil chamber and the oil drain port, and the width of the land is formed smaller than the opening width of the oil port, so that the spool A space is formed between the land and the oil port when the land is at an intermediate position, and the first oil chamber and the oil drain port are communicated through the space and the oil port. An oil passage switching valve according to claim 1.