KR101528926B1 - Cylinder, in particular a transmission cylinder for the control device of a hydraulic clutch - Google Patents

Abstract

The present invention comprises at least one body (12) having an inner bore (18) through which the piston (20) can move axially along the axis (X) of the cylinder; Is connected to a piston (20) having an insert (32) by ball-joint articulating means (30) and includes a radial collar (76) and is arranged axially rearward of the ball-joint joint A cylinder (10) comprising a control rod (28) wherein a collar (76) of the rod (28) is arranged such that when the control rod (28) is angularly displaced relative to an angle Characterized in that the collar (76) of the control rod (28) comprises a front face (78) which cooperates with the rear edges (80, 82) of the piston (20) .

Description

TECHNICAL FIELD [0001] The present invention relates to a cylinder for a control device of a hydraulic clutch, and more particularly to a transmission cylinder for a hydraulic clutch,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder of an apparatus for hydraulic actuation of a clutch, and more particularly to a transmission cylinder.

The present invention relates to a cylinder of an apparatus for the hydraulic actuation of an automotive clutch, more particularly to a transmission cylinder, comprising at least one element having an inner bore capable of axial movement of the piston along the main axis X; A hydraulic chamber bounded by the front portion of the body of the cylinder, by the bore itself, and by one of the front faces of the piston; Sealing means inserted radially between the piston and the body of the cylinder; A control rod connected to the piston by a split system formed by a front end of the rod operable with an additional portion of the insert mounted in the rear cavity of the piston, the control rod comprising at least one front operating position and a rear stop means Including a rear axial end which can be connected to a drive mechanism, such as a clutch pedal, and a rear collar, axially arranged under the segment means, for selectively controlling the axial displacement of the piston between the extreme rear end stop positions determined by To the cylinder including the control rod.

Hydraulic cylinders of the type known in the art as "transmission" or " reception "cylinders for use in this type of various cylinders, particularly for example hydraulic clutches or braking systems, are already known.

Document FR-A-2.794.507 discloses an example of a transmission cylinder of a control device comprising a piston made of a plastic insert and an aluminum tubular sleeve, which operates through a split arrangement with a control rod of the piston.

To reduce the cost, and in particular the cost of manufacturing such a piston for a cylinder, it has been proposed that the piston should be made of a thermoplastic material such as plastic or thermoplastic material which is generally moldable, in particular "thermodur ".

In a given piston design, the piston control rod includes a radial collar, and the rear surface of the collar has a connecting means (not shown) for connecting the control rod to the piston when the piston is moved outward (compression) Lt; / RTI >

This connection means is obtained, for example, by an elastic washer, which on the one hand, together with the rear face of the collar, on the other hand axially with the rear end of the piston, Lt; / RTI >

However, in the process, for example, at the attachment of the rear end of the control rod to the clutch pedal, the enlargement angle possible by the ball joint is such that the outer radial circumference of the collar exerts a bending force on the cylindrical wall of the piston It is required to enlarge the angle between the control rod and the main axis line X of the cylinder in which the piston moves in the axial direction.

Although applying such a bending force on the metal sleeve of a piston of the type mentioned above does not cause any problems with mechanical stability, it is not the case when the piston is made of thermoplastic or similar material.

In fact, even though the pistons made in the described manner generally have excellent stiffness characteristics when subject to axial forces such as those exerted by the rods during the compression phase, such characteristics may cause bending, such as may occur in a radial collar, Or less, and consequently there is a risk of piston failure during the assembly operation described above.

The object of the present invention is to solve this problem by presenting a piston made of plastic or similar material with both reliability and economical productivity.

To this end, the invention is characterized in that the collar of the rod comprises a front face, the front face of which, when the control rod is arranged at an angle larger than that which is determined with respect to the axis X, Which acts in conjunction with the rear edge of the piston to be added.

As a result of the present invention, no bending force will be applied by the collar of the control rod during assembly of the cylinder, and it is therefore possible to ensure the integrity of the plastic piston once the assembly work on the vehicle is completed.

However, in the design according to the invention, the rear piston stop which determines the stop position can not be obtained as a result of the cooperation of the stopper itself and the rear cylindrical edge of the piston.

Advantageously, the extreme rearward rest position of the piston is located on the rear face of the radial collar of the control rod, and on the body of the cylinder, which is arranged at right angles to the axis X of the piston, Such as the end of the clip, which is supported by the rear portion of the clip.

According to another aspect of the present invention,

The insert has axially a front portion fixed by first means for axially holding the insert in the piston and the first means can cooperate with the inner wall of the front section of the cylindrical cavity of the piston.

The insert comprises axially a rear portion including a recessed groove opening axially rearwardly and the recessed groove can cooperate with an additional convex sphere of the control rod to form a ball-joint joint between the control rod and the piston .

At least a part of the rear part of the insert is formed in one of the rear sections of the rear section of the cylindrical cavity of the piston in such a way as to form a second means for axially holding the insert in the piston, Can act together with the side walls.

The concave grooves of the insert are axially rearward bounded by a retaining finger which is generally axially oriented and circumferentially distributed about the concave groove and which retains the insert and the piston and control rod on the axis Direction of the sphere.

The retaining fingers of the insert are resiliently resiliently in a generally radial direction with respect to the main axis line X to allow introduction of the convex spheres constituting the ball-joint into the concave grooves of the insert, irrespective of the presence of the piston around the insert It can be deformed.

The rear free end of each retaining finger curved towards the main axis X has a radial play with respect to the inner wall of the rear section of the cylindrical cavity of the piston which is located inside the inner cavity of the piston, In a manner that allows radial elastic deformation of each of the radial retention fingers of the control rod with the insert, particularly when the piston, insert and control rod are assembled, the sphere of the rod is once inserted into the recessed groove of the inserted surface insert with the piston So that it can be introduced in the axial direction.

During the assembly of the piston, insert and control rod, the angular position of the control rod over a predetermined angle creates an axial compressive force on the rear upper piston edge, by the front face of the collar of the rod, And when the control rod is in the final position above the limit value, the sphere is subjected to a radial force to deform the retaining finger, and once the assembly is completed, the integrity of the piston is ensured Disengages the sphere of the control rod from the insert groove.

The rear face of the radial collar of the control rod can cooperate with the rear stop means and thus determine the extreme rear stop position of the piston.

The rear face of the stop of the radial collar is formed with a convex spherical surface which can cooperate with the additional face of the piston's rear stop means, From an initial coaxial angular position to an angular position where the rear end of the control rod can be connected to an actuating means such as a clutch pedal if the rod is at a predetermined angle relative to the main axis X approximately equal to the predetermined angle Centered on the center of the convex sphere forming the articulated ball-joint between the control rod and the insert, so that the piston can not move axially from the extreme rear position when it is temporarily displaced.

The axial retention force of the insert with respect to the piston applied by the first or second means is such that the axial retention force of the insert against the piston applied by the means for returning the actuating means and returning the piston to the extreme rear position Direction axial return force.

The piston is made of a thermoplastic material.

It is customary to refer to terms such as "axial", "forward", "rear", "upper" and "lower" and "longitudinal", " The same direction is used to represent each of the elements, according to the definition disclosed in the detailed description and for the three-sided body (L, V, T) shown in the figure.

In the latter part of the specification, similar or identical elements will be denoted by the same reference numerals.

Fig. 1 shows an exemplary embodiment of a cylinder 10 shown here in the form of a hydraulic transmitter of a control device for a vehicle clutch.

In a known manner, a controller (not shown) of this nature includes a transmission cylinder 10 configured to be connected to the receiving cylinder by a conduit.

The transmission cylinder 10 shown in Fig. 1 corresponds to the configuration of the cylinder at the time of transfer, in other words, in view of entering into operation before the cylinder is assembled in the vehicle.

The cylinder 10 includes at least one generally tubular body 12 axially extending along a longitudinally oriented axis X which is at least two parts, (12A) and a rear portion (12B).

The front concealed portion 12A is axially bounded from the front by the transversely oriented base 14 and the axially open rear portion 12B is provided on the rear end of the body 12 And can be closed by the mounted cap 16.

The main body 12 of the cylinder 10 includes an inner bore 18 in which the piston is fixed to the main bore X at least between an extreme forward position known as the operating position and a rearmost position, In the outward direction or in the return direction.

Advantageously, the piston 20 is made of a thermosetting plastic material, such as plastic or a thermoplastic, preferably a thermodew or similar material.

At its forward end, the cylinder 10 includes a hydraulic chamber 22 having a variable volume, which includes a base 14, an inner bore 18, and a piston (not shown) of the front portion 12A of the body 12 of the cylinder. 20 from the front side in the axial direction to the rear side.

The cylinder 10 includes a piston 20 and a seal 26 means radially interposed between the body 12 of the cylinder and the control rod 28 which is connected to the joint 30 of the ball- And is movably connected to the piston (20).

The ball-joint joint 30 includes a plurality of ball-joint joints 30 which are mounted on a cavity 34 arranged in the rear portion of the piston 20 and which have a shape in front of the front end of the control rod 28, As shown in Fig.

In general, the receiving cylinder (not shown) of the hydraulic control device for the clutch system structurally similar to the transmission cylinder 10 described above includes a cylinder that can be axially moved within the body and bounds the variable volume hydraulic chamber do.

The control rod 28 of the piston of the transmission cylinder 20 is fixed to the rear axially end 28B which can be connected to the actuating means (not shown), in particular the clutch pedal or actuator, .

The actuating means allows the driver of the vehicle to selectively control the clutch release operation by the axial displacement of the piston 20 from the last stopping position to the forward operating position using the driver's foot in the case of the clutch pedal .

It will be recalled that, in operation, the transmission cylinder of the hydraulic clutch control drives the fluid, such as oil, contained in the hydraulic chamber 22 towards the receiving cylinder.

To this end, the front portion 12A of the body is an orifice (not shown) extending laterally at an angle of 45 degrees with respect to the main axis X and having one end extending over the transverse base portion 14 of the body 12 40 with a hydraulic chamber 22 and the other end of which can be connected to the connecting piece 42.

Figure 1 shows the end of such a connecting piece 42 connected to the coupling 38 and is preferably held in place by a locking means 44 such as a pin on this end, And is held in place by engagement.

The other end of the connecting piece 42 is connected in a manner similar to the coupling of the receiving cylinder 10 and the hydraulic chamber of each of the transmissions so that they are interconnected.

In this manner, when the clutch is engaged, the volume of the hydraulic cylinder 22 of the transmission cylinder 10 reaches a maximum level, while the volume of the control chamber of the receiving cylinder is at a minimum level.

During clutch release, the actuation of the control rod 28 causes the piston 20 to move axially outward, which has the effect of reducing the volume of the hydraulic chamber 22, Is transferred into the control chamber of the receiving cylinder, whereby the volume of the control chamber is increased.

Variation of the volume of the fluid in the control chamber of the receiving cylinder may cause the piston to move directly or indirectly through the intermediary of the rod acting on the mechanical stop and the fork in the case of a hydraulic stop forming at least one diaphragm of the clutch The clutch release means, which is a general stop associated with the clutch, is moved and acted upon.

The transmission cylinder 10 generally includes a piston return means, such as a spring, arranged in the hydraulic chamber and acting between the inner wall of the transverse base piece 14 and the front portion 24 of the piston 20.

Advantageously, and as can also be seen in FIG. 1 for the cylinder 10, if the actuating means itself, such as the clutch pedal itself, has means for returning the piston axially by applying a pulling force on the control rod, It may not be required.

In this manner, when the driver relieves the pressure on the pedal (or when the actuator is returned to the initial clutch engagement position), the summoning means return the piston 20 of the transmission cylinder 10 toward the rearmost stop position And in the receiving cylinder, the piston return spring is again pressed by the diaphragm and moved axially rearward, causing the piston of the receiving cylinder to return to the initial stop position.

Preferably, when the cylinder comprises a means for summoning the piston in the form of a coil spring, the inner wall of the transverse base portion 14 comprises centering means, which are arranged on the axis of a spring (not shown) Directional front end, the rear end axially penetrating the rear end of the piston 20, with an additional housing 48 at its front end for this purpose.

Advantageously, no return spring for this piston 20 is required, which means that the transmission piston 10 can be simplified by simplifying the piston and / or the centering means, thereby reducing manufacturing costs .

Preferably, the central portion of the transmission piston 10 formed by the portion 12B of the body includes means for securing the transmission cylinder 10 on a fixed portion of the vehicle, such as a pedal.

This mounting means is constituted by a plate 50 having a lobe (not shown in Fig. 1) with holes provided for, for example, fastening means such as screws, which lobes are transverse, i.e., X in the radial direction.

The transmission cylinder 10 further includes an additional connection portion 52 arranged in the center direction and forming a part of the portion 12B of the main body and the purpose of further including the additional connection portion is that the hydraulic chamber of the cylinder 10 22 are connected in particular to a reservoir (not shown) so as to be able to replenish fluid to the hydraulic control device in general.

This supplemental reservoir is typically mounted on the outside of the transmission cylinder 10 and is connected to the upper free end of the connection 52 through a duct 54 and extends across the body 12 within the center of the inner bore 18 And a channel 56 radially outwardly open.

The sealing portion of the hydraulic chamber 22 against the outside is ensured by the sealing means 26 and in this case the sealing means 26 is provided with a composite type of front seal which is associated with the cap 60 and the rear sealing portion 62 (58). ≪ / RTI >

Each seal 58 and 62 is mounted to an additional housing of the body 12 that includes a radial lip that forms a seal box and cooperates with the outer cylindrical surface 64 of the piston 20.

In operation, the forward seal 58 ensures rigidity between the hydraulic chamber 22 and the supplemental channel 56, which is axially outwardly open between the seals 58 and 62, and the rear seal 62, Ensures the rigidity between the piston 20 and the body 12B behind the channel 56. [

However, even if the rear sealing portion 62 guarantees permanent durability regardless of the position of the piston 20, this point does not apply in the case of the front sealing portion 58. In this case, the piston 20 Is in the rearmost stop position, it is required to allow replenishment of the fluid in the chamber 22 through the channel 56.

To achieve this, the front end of the piston 20 includes an axial groove 66 in the axial direction and in opposition to the lip of the forward seal 58, which is circumferentially distributed, (20) and creates an opening between the lip of the seal (58) and the outer cylindrical surface (64) of the piston (20), allowing fluid to flow through the opening, .

This replenishment occurs only when the piston 20 is in the rearmost stop position, as shown in FIG. 1, and the rearmost position is accurately determined by the rear axial stop means such as the clip 68.

In fact, once the piston 20 has been moved by the control rod 28 and remains in a rest position to be displaced axially in the outward direction, the axial groove 66 is displaced upwardly from the lip of the seal 58 And the lip of the seal 58 cooperates with the outer cylindrical surface 64 of the piston 20 to seal the hydraulic chamber 22.

Preferably, the transmission cylinder 10 includes a guide ring 70 which acts in front of the axial and forward sealing portion 58 at the intersection of the front portion 12A and the rear portion 12B of the body of the cylinder , The ring (70) includes an initial front guide surface (72) for the piston (20).

Advantageously, the second rear guide surface 74 is configured such that when the piston 20 is actuated and moves axially in two directions, i.e., outward and return directions, And is formed directly on the inner bore 18 of the rear portion 12B of the body of the cylinder 10 so that it is accurately guided by the rear surface 74 and the rear surface 74. [

In the embodiment shown in FIG. 1, the control rod 28 includes a radial collar 76 axially arranged behind the ball-joint joint 30.

As described in the foregoing, when the transmission cylinder 10 as shown in the transmission position described in detail in Figures 1 and 2 is to be installed in the vehicle, the first essential step is to move the transmission cylinder 10 to the mounting area Attaching the rear end portion 12B of the control rod 28 to an operating means such as a clutch pedal (not shown) before performing the second step of assembling the vehicle to the surface by, for example, will be.

It may be necessary to tilt the control rod for attachment of the control rod 28, that is, for example, as shown in Fig. 3 as compared to Fig. 2, at a predetermined angle It is necessary to arrange the control rod.

Depending on the state of the art, in the course of this operation in the transmission cylinder, the radial collar 76 generally cooperates with the piston 20 of plastics material by applying a bending force on the inner wall, May occur.

In fact, as already mentioned, plastics or thermoplastics are particularly vulnerable to bending forces.

Particularly, in order to solve this problem, the present invention prevents the radial collar 76 from applying a bending force to the piston anymore, thereby avoiding the risk of damage to the piston 20 when the cylinder 10 is installed We suggest the original design that can be.

In accordance with the present invention, the radial collar 76 of the control rod 28 of the piston 20 is configured such that when the control rod 28 is displaced at an angle greater than or equal to a predetermined angle [theta] And a collar 76 of the rod 28 exclusively includes an axial compressive force, i.e., an axial force exerted from the rear to the front, Is applied to the front surface.

As a result of the arrangement according to the invention, the piston 20 is protected from application of significant force from the collar, which can cause damage, so that the control rod 28 is moved in the direction of the rod 28 As shown in Fig. 3 in which the control rod 28 is inclined upward or downward at a predetermined angle substantially equal to the angle [theta] from a position as shown in Fig. 2 in which the control rod 28 is generally coaxial with the axis X Lt; RTI ID = 0.0 > angled < / RTI >

Advantageously, when the angle of the rod 28 reaches an angle? Value, the front face 78 of the collar 76 cooperates with the rear vertical face 82 comprising the rear circular edge 80 of the piston .

Preferably, the insert 32 has an axial retention of the insert 32 in the piston 20, which can act in conjunction with the inner wall 86 of the front section 88 of the cylindrical cavity 34 of the piston 20. [ And axially includes a front portion 32A on which the initial means 84 is mounted.

Advantageously, the initial means 84 of axial retention is formed by at least one circular rim 90, three of said at least one circular rim are shown herein, which are the front face 32A of the insert, And preferably has an axial shape in the form of a tooth of the saw.

Advantageously, the front portion 32A of the insert 32 includes an axial groove 92 in the center and the groove extends laterally and opens to the rear portion 32B of the insert 32. [

Thus, the insert 32 axially includes an additional rear portion 32B including a recessed groove 94 that opens axially rearward.

The concave groove 94 is an additional convex sphere 96 forming the front end 28A of the control rod 28 in such a manner as to constitute a ball-joint 30 between the control rod 28 and the piston 20, Lt; / RTI >

The ball joint 30 is achieved by reversing the element in such a way that the ball 96 is supported by the insert 32 and the additional groove 96 forms part of the control rod 28. [

Advantageously, at least a portion of the rear portion 28B of the insert 32 is moved into the groove 92 by the presence or absence of the sphere 96 of the rod 28 in the groove 94, May act together with the inner wall 98 of the rear section 88B of the cylindrical cavity 34 of the piston 20 in such a manner that the means 100 is formed in the piston 20.

Preferably, the second means 100 of the retaining comprises a rigid portion of the insert 32 and the outer diameter of the insert is such that the insert 32 is axially biased by the force into the cavity 34 of the piston 20 Approximately equal to the inner diameter of the rear section 88B of the cavity 34 bordered by the inner wall 98 in such a manner as to be mountable in the cavity.

The outer diameter of the convex sphere 96 is greater than or equal to the inner diameter of the concave groove 94 of the insert 32 so that the wall 98 of the cavity 34 of the piston 20 and the insert 34, Or to increase the degree of such cooperation so that the control rod 28 on the insert 32 does not cause axial displacement of the insert 32 relative to the cavity 34 and hence to the piston 20. [ Thereby increasing axial retention by increasing the maximum amount of axial traction force that needs to be applied.

 Advantageously, the concave grooves 94 of the insert are axially bounded rearward by the retaining fingers 102, and the retaining fingers are generally oriented in a "petal" arrangement around the recessed grooves 94 in the axial orientation And distributed.

An axial slit (104) extends between each finger (102).

The fingers 102 can act in conjunction with the rear portion of the sphere 96 and the rear portion moves in a manner that moves the control rod 28 and connects the rod 28 with the insert 32 and the piston 20 And is almost entirely enclosed in the groove 94 of the insert 32.

According to one important characteristic of the invention, the retaining fingers 102 of the insert 32 have convex spheres 96 forming a ball-joint, with or without the piston 20, around the insert 32 Can be elastically deformed in a generally radial direction with respect to the main axis line X so as to be introduced into the concave groove 94 of the insert.

Advantageously, in the process of mounting the components of the transmission cylinder 10, the assembly of the control rod 28 and the insert 32 is carried out before or after the assembly of the insert 32 and the piston 20.

According to the initial possibility, the assembly of the parts shown in Fig. 4 forming the movable part of the transmission cylinder 10 is carried out in the following manner. The insert 32 and the piston 20 are first formed into a single subassembly, after which the sphere of the control rod 28 is inserted.

In a second possibility, the control rod 28 and the insert 32 are first assembled, and then the blended assembly is inserted axially forward from the rear in the groove 34 of the piston 20.

Advantageously, the rear free end of each of the retaining fingers 102 is curved toward the main axis X and the fingers 102 engage with the inner walls of the rear section 88B of the cylindrical cavity 34 of the piston 20, Lt; RTI ID = 0.0 > 98 < / RTI >

The radial clearance of the finger 102 of the insert 32 with respect to the piston 20 is greater than the radial clearance of the sphere 96 of the control rod 28 with the insert 32 within the inner cavity 34 of the piston 20. [ Is determined to allow radial elastic deformation of each of the axial retention fingers (102).

During the assembly of the control rod 28, the insert 32 and the piston 20 of the transmission cylinder, this radial clearance is maintained even when the insert 32 is initially inserted as part of the piston 20, To be introduced axially into the recessed grooves of the insert 32. In this way,

As shown in Fig. 5, the present invention also has the advantage of maintaining the integrity of the piston 20 when a member forming the movable part of the cylinder 10 is assembled.

In fact, during the act of inserting the sphere 96 of the rod 28 into the concave groove 94 of the insert, the control rod 28 is positioned such that the front face 78 is perpendicular to the rear face 80 of the piston 20 Lt; RTI ID = 0.0 > 82 < / RTI >

During the assembly of the piston 20, the insert 32 and the control rod 28, if the angular position of the control rod 28 exceeds a predetermined angle?, It is on the rear edge 80 of the piston 80 (In the outward direction) by the front face 78 of the collar 76, which exceeds the limit.

Advantageously, for this limit, the control rod is reinforced and the sphere 96 exerts an external radial force on the finger 102, which fingers the sphere 96 of the rod 28 automatically, (32).

This automatic disengagement can ensure the integrity of the piston 20 of the transmission cylinder after the piston 20, the insert 32 and the control rod 28 are assembled.

The rear face 106 of the radial collar 76 of the control rod 28 can work together with the rear stop means 68 to determine the final stop position of the piston 20 .

Preferably, the rear stop means 68 consists of a clip which is supported by the body 12 of the cylinder 10 and which is generally transversely oriented, that is to say about the main axis line X Quot; U "shape that includes two arms 108 that extend into the interior of the inner bore 18 at right angles.

Advantageously, the rear face 106 of the stop of the radial collar 76 comprises a convex spherical surface that can cooperate with the additional face 110 of the arm 108 of the clip of the rear stop of the piston 20.

Advantageously, the rear convex spherical surface 106 is configured such that when the control rod 28 of the piston 20 is displaced in an angular direction relative to the axis X, Centered on the center 0 of the convex sphere 96 forming the ball-joint joint 30 between the insert 28 and the insert 32.

This is particularly advantageous when the control rod 28 is moved from its initial position coaxial with the main axis X in order to allow the rear end 28B of the control rod 28 to be connected to an actuating means such as a clutch pedal. (28) is displaced by a predetermined angle at least equal to a predetermined angle (?) To an inclined position inclined with respect to the main axis line (X).

Advantageously, the fact that the rear extreme position of the piston 20 is maintained can be ensured in the axial position of the groove 66 with respect to the lip of the front seal 58, (22) can be replenished effectively.

In fact, the angular displacement of the control rod 28 in a member of this rear sphere 106, centered on the center O of the sphere 96, And a force acting on the collar 76 and this force is transmitted to the piston 20 by the front face 78, which forces the piston 70 to move in the axial direction The piston can be displaced axially forward toward the point where fluid replenishment into the chamber 22 through the groove is prevented.

Advantageously, the control rod 28 includes a pair of axially aligned surfaces 112 (see FIG. 1) arranged behind both arms 108 and collar 76 of the clip to ensure at least one angular clearance of angle? Relative to the ball- ).

The axial retention force of the insert 32 with respect to the piston 20 applied by the first means 84 and / or the second means 100 is preferably controlled by the returning means of the actuating means 28 and is greater than the backward axial return force which allows return of the piston 20 to the original rearward position.

Advantageously, as described above, the returning orifice of the piston 20 in the form of a coil spring arranged in the hydraulic chamber 22 of the conventional cylinder 10 can be omitted, thereby reducing the manufacturing cost and the cost of the transmission cylinder 10. [ Can be achieved.

Other features and advantages of the invention will be apparent from the following detailed description, and will be better understood by reference to the following drawings.

1 shows an axial section for one embodiment of a cylinder according to the invention,

Fig. 2 is an axial sectional view showing in detail the rear part of the cylinder according to Fig. 1, in which the piston is at its rear end position, is generally coaxial with the axis X of the cylinder, In the axial position corresponding to the position occupied in the free state after assembly of the cylinder of the control rod,

Fig. 3 is an axial cross-sectional view similar to Fig. 4, in which the front face of the collar applies an axial force on the rear edge of the piston, and particularly to an angular position occupied by the rod while the rear end is attached to the means of actuation In which the control rod exists at a position displaced in an angular direction with respect to an axis X of a corresponding predetermined angle,

4 is an enlarged perspective view of the control rod of the piston, the insert and the piston prior to assembly into the subassembly,

5 is an axial cross-sectional view of the subassembly shown in Fig. 4, showing the disengagement of the sphere of the control rod from the housing of the insert when the rod is angularly inclined over a predetermined angle relative to the axis X drawing.

[Description of Reference Numerals]

10: cylinder 12: main body 18: inner bore

20: piston 28: control rod 28A: front end of the control rod

30: joint 32: insert 76: radial collar

78: front face of the radial collar 80: rear circular edge of the piston

82: Vertical plane of the rear circular edge of the piston

102: retaining finger 106: rear face of the radial collar

Claims (14)

At least one body (12) having an inner bore (18) through which the piston (20) can move axially along the main axis line (X); A hydraulic chamber 22 bounded by the front portion 12A of the body 12 of the cylinder 10, the inner bore 18 and the front face 24 of the piston 20; Sealing means (26, 58, 60, 62) interposed radially between the piston (20) and the body (12) of the cylinder (10); A ball-joint joint (not shown) consisting of the front ends 28A, 96 of the control rod 28, which can operate with an additional portion 94 of the insert 32 mounted on the rear cavity 34 of the piston 20 (20) between the at least one outwardly operative position and the rearmost stop position determined by the rear stop means (68, 108, 110) during operation and connected to the piston A control having a rear axial end 28B which can be connected to an actuating means such as a clutch pedal and a radial collar 76 arranged axially rearward of the joint 30 for the selective control of the axial displacement In the cylinder 10 including the rod 28, The collar 76 of the control rod 28 is arranged such that when the control rod 28 is angled beyond a certain angle θ determined relative to the axis X the collar 76 of the control rod 28 (78) which cooperates with the rear edges (80, 82) of the piston (20) to which the piston cylinder. The method according to claim 1, The insert (32) axially includes a front portion (32A) provided with initialization means (84, 90) for axially holding the insert (32) in the piston (20) 84, 90) is operable together with the inner wall (86) of the front section (88A) of the cavity (34) of the piston (20) cylinder. 3. The method according to claim 1 or 2, The insert (32), when opened axially rearward, cooperates with a convex spherical body (96) attached to the control rod (28) to provide a ball-like joint between the control rod (28) (32B) including a recessed groove (94) capable of forming a recess (30) in the axial direction cylinder. The method of claim 3, At least a portion of the rear portion 32B of the insert 32 is located within the groove 94 of the cavity 34 of the piston 20, regardless of whether or not the sphere 96 of the control rod 28 is present in the groove 94. [ Characterized in that a second axial holding means (100) of the insert (32) can be formed in the piston (20) in cooperation with the inner wall (98) of the rear section (88B) cylinder. 5. The method of claim 4, The recessed groove 94 of the insert 32 is bounded axially rearward by a retaining finger 102 and the retaining finger 102 is generally axially oriented and extends circumferentially about the recessed groove 94. [ And is operable in cooperation with the rear of the sphere (96) to connect the control rod (28) with the insert (32) and the piston (20). cylinder. 6. The method of claim 5, The retaining fingers 102 of the insert 32 are configured such that the convex spheres 96 forming the ball-joint are positioned on the insert 32, regardless of whether or not the piston 20 is present around the insert 32. [ And is elastically deformable in a substantially radial direction with respect to the main axis line (X) so as to be introduced into the concave groove cylinder. The method according to claim 6, The rear free end of each of the retaining fingers 102 curved toward the main axis X is connected to a radial clearance (not shown) for the inner wall 98 of the rear section 88B of the cavity 34 of the piston 20 which play together with the insert 32 inside the inner cavity 34 of the piston 20 in the radial direction of each axial retention finger 102 of the sphere 96 of the control rod 28 Is determined to allow deformation. cylinder. The method of claim 3, The angular displacement of the control rod 28 beyond a certain angle? Is such that the axial compression force by the front face 78 of the collar 76 of the control rod 28 is transmitted to the rear edges 80, 82 of the piston 20, The control rod 28 is in the extreme position and the sphere 96 is configured to apply a radially outward directional force to the elastic retaining fingers 102 and the resilient retaining fingers are deformed such that the sphere 96 of the control rod 28 is displaced in the groove 32 of the insert 32 in a manner that ensures the integrity of the piston 20 after the assembly step. (94). ≪ RTI ID = 0.0 > cylinder. 3. The method according to claim 1 or 2, The rear face 106 of the radial collar 76 of the control rod 28 may cooperate with the rear stop means 68,108 and 110 to thereby determine the final stop position of the piston 20 Featured cylinder. 10. The method of claim 9, The rear face 106 of the stop of the radial collar 76 can cooperate with the additional face 110 of the rear stop means 68,108 of the piston 20, Since the control rod 28 is angled with respect to the main axis X at a given angle which is not more than a predetermined angle? From the initial position where the control rod 28 is substantially coaxial with the main axis X, In such a manner that when the piston 20 is momentarily angularly displaced to an angular position at which the rear end 28B can be connected to an actuating means such as a clutch pedal, the piston 20 remains axially immovable at its rearmost position, Characterized in that it is in the form of a convex spherical surface centered on the center (O) of the convex spheres (96) forming the ball-type joint (30) between the insert (28) and the insert cylinder. 11. The method of claim 10, Wherein the axial retention force of the insert (32) relative to the piston (20) applied by the first means (84) is greater than the axial return force in the backward direction and the retraction force on the control rod (28) Is capable of returning the piston (20) to its rearmost position cylinder. 11. The method of claim 10, Wherein the axial retention force of the insert (32) relative to the piston (20) applied by the second means (100) is greater than the axial return force of the backward direction, Is capable of returning the piston (20) to its rearmost position cylinder. 11. The method of claim 10, Wherein the axial retention force of the insert (32) relative to the piston (20) applied by the first and second means (84, 100) is greater than the axial return force in the backward direction, 28) is capable of returning the piston (20) to its rearmost position cylinder. 3. The method according to claim 1 or 2, Characterized in that the piston (20) is made of a thermoplastic material cylinder.

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