JP7545241B2 - Valve device - Google Patents

Description

This invention relates to a valve device.

An example of this type of valve device is one that is attached to an actuator or damper and is used with a housing having a first valve hole and a second valve hole that open in parallel in the same direction from the outside, a cylindrical valve seat body inserted into the first valve hole, a valve body and a switching valve inserted slidably into the valve seat body, a spring that biases the valve body toward the valve seat body, a proportional solenoid attached to the housing to apply thrust to the valve body and the switching valve, and a relief valve inserted into the second valve hole.

The switching valve opens and closes the flow path, and can be switched between an open and closed state by a proportional solenoid. The thrust of the proportional solenoid acts on the valve body via the switching valve, allowing the opening pressure at which the valve body seats on the valve seat to be adjusted.

The relief valve is configured with a relief valve body that is inserted into the second valve hole so as to be movable in the axial direction of the second valve hole, a spring retainer that is screwed to the open end side of the second valve hole, and a spring that is interposed between the valve body and the spring retainer. In a valve device configured in this manner, the second valve hole is blocked by the spring retainer, and the initial load with which the spring presses the valve body is set by adjusting the position of the spring retainer (see, for example, Patent Document 1).

In this way, the spring bearing is used to adjust the initial load of the spring that sets the opening pressure of the relief valve, but if it becomes loose due to external vibration and falls off the housing, hydraulic oil will leak from the actuator to which the valve device is applied. Therefore, in the valve device, after the spring bearing is screwed into the housing, the boundary between the spring bearing and the housing around the spring bearing is crimped with a punch to restrict the rotation of the spring bearing relative to the housing and prevent the spring bearing from falling off the housing (see, for example, Patent Document 2).

JP 2001-074154 A JP 2000-046088 A

Although tightening with such a punch can prevent the spring bearing from falling off, if the tightening is insufficient, the rotation of the spring bearing relative to the housing cannot be restricted, and the spring bearing may fall off the housing.

In addition, if the spring bearing is fixed by tightening with a punch, it becomes impossible to rotate the spring bearing, making it impossible to adjust the second valve in the second valve hole.

The present invention aims to provide a valve device that not only reliably prevents the spring bearing from falling off the housing and eliminates the risk of liquid leakage, but also allows for valve adjustment within the second valve hole.

The valve device of the present invention comprises a housing having a first valve hole and a second valve hole that open in parallel in the same direction from the outside, a first valve having a first valve body inserted into the first valve hole and driven by a solenoid, a second valve inserted into the second valve hole, and a plate connected to the solenoid and fastened to the housing to block a portion of the first valve hole and the second valve hole. The second valve comprises a second valve body inserted into the second valve hole so as to be movable in the axial direction of the second valve hole, a spring bearing that is screwed to the open end side of the second valve hole to block the second valve hole and has an adjustment part at its end that allows rotational operation by an external tool, and a spring interposed between the second valve body and the spring bearing, and the plate faces the end of the spring bearing in the axial direction of the second valve hole while allowing connection to the adjustment part of the tool. In a valve device configured in this manner, the plate that prevents the first valve housed in the first valve hole from falling out faces a part of the spring bearing of the second valve housed in the second valve hole arranged in parallel to the first valve hole, not only preventing the second valve from falling out of the second valve hole, but also making it possible to rotate the spring bearing using a tool.

The plate in the valve device may face a position that avoids the center of the spring bearing in the axial direction of the second valve hole. With a valve device configured in this way, when a tool is connected to the adjustment unit, the tool can be connected to the center of the spring bearing, making it easier to rotate the spring bearing.

The valve device may be configured so that the plate has a semicircular notch, with the periphery of the notch facing the spring bearing. With a valve device configured in this manner, the notch provides a clearance that allows a tool to be connected to the adjustment portion of the spring bearing, and while the plate blocks part of the second valve hole, it does not prevent easy connection of the tool to the adjustment portion. In addition, because the notch is semicircular in shape, a large area of the adjustment portion of the spring bearing can be exposed, making it easy to connect the adjustment portion of the tool and to rotate the spring bearing.

The valve device of the present invention not only reliably prevents the spring bearing from falling off the housing, eliminating the risk of liquid leakage, but also makes it possible to adjust the valve in the second valve hole.

FIG. 2 is a cross-sectional view of a valve device according to an embodiment. 1 is a circuit diagram of a damper to which a valve device according to an embodiment is applied; FIG. 2 is a side view of the valve device according to the embodiment. FIG. 11 is a side view of a valve device according to a first modified example of the embodiment. FIG. 11 is a side view of a valve device according to a second modified example of the embodiment.

The present invention will be described based on one embodiment shown in the drawings. As shown in FIG. 1, the valve device V in one embodiment is configured to include a housing H having a first valve hole 1 and a second valve hole 8 that open in parallel in the same direction from the outside, a first valve V1 having a first spool 4 and a second spool 5 as a first valve body that is inserted into the first valve hole 1 and driven by a solenoid Sol, a second valve V2 that is inserted into the second valve hole 8, and a plate 6 that is connected to the solenoid Sol and fastened to the housing H.

The valve device V is applied to a damper D, for example, as shown in FIG. 2. Specifically, the valve device V is provided midway through a damping flow path CP through which liquid flows as the damper D expands and contracts, and provides resistance to the flow of liquid passing through the damping flow path CP, allowing the damper D to generate a damping force.

Each part of the valve device V will be described in detail below. First, in this example, the housing H comprises a cylindrical first housing H1 and a cylindrical second housing H2 attached to the outer periphery of the first housing H1. The first valve hole 1 is provided in the first housing H1 and opens from the outside of the first housing H1, and in this case, communicates with the outside from both axial ends of the first housing H1. In this example, the first valve hole 1 penetrates the first housing H1 from left to right in FIG. 1, but it may also be a blind hole that opens from the left end side.

The first valve hole 1 provided in the first housing H1 has, in order from the right end side in FIG. 1, a spring receiver mounting portion 1a to which the spring receiver 7 is mounted, a sleeve accommodating portion 1b to which the first sleeve 2 and the second sleeve 3 are accommodated, and a plate insertion portion 1c to which the plate 6 is attached.

The spring receiver attachment portion 1a is formed at the right end of the first housing H1 in FIG. 1 and has a screw portion 1d on the left side in FIG. 1. In addition, the inner diameter of the spring receiver attachment portion 1a to the right of the screw portion 1d in FIG. 1 is larger than that of the screw portion 1d.

The sleeve accommodating portion 1b is composed of a tip portion 1e formed to the left of the screw portion 1d in FIG. 1 with an inner diameter larger than that of the screw portion 1d, an intermediate portion 1f formed to the left of the tip portion 1e in FIG. 1 with an inner diameter larger than that of the tip portion 1e, and a rear end portion 1g formed to the left of the intermediate portion 1f in FIG. 1 with an inner diameter larger than that of the intermediate portion 1f, and forms part of the first valve hole 1. Therefore, a step portion 1h is formed between the tip of the sleeve accommodating portion 1b and the rear end of the spring receiving attachment portion 1a.

The plate insertion portion 1c is formed at the left end of the first housing H1 in FIG. 1, and is formed to the left of the rear end portion 1g in FIG. 1 with an inner diameter larger than that of the rear end portion 1g, forming part of the first valve hole 1.

In this example, the first housing H1 has a first port 1i that opens radially from the outer periphery and communicates with the tip end 1e, a second port 1j that opens radially from the outer periphery and communicates with the middle portion 1f, and a third port 1k that opens radially from the outer periphery and communicates with the rear end 1g.

Furthermore, the second housing H2 is attached to the side of the first housing H1. The second housing H2 is integrated with the first housing H1 and constitutes the housing H together with the first housing H1. The second housing H2 is provided with a second valve hole 8 that opens in parallel in the same direction as the first valve hole 1 from the outside of the left end in FIG. 1, a fourth port 10 that penetrates from the upper end to the lower end in FIG. 1 and communicates with the second valve hole 8 midway, and a fifth port 11 that opens from the upper end in FIG. 1 and communicates with the second valve hole 8. In this way, the first valve hole 1 and the second valve hole 8 are provided in parallel and open from the ends of the housing H.

When the second housing H2 is attached to the first housing H1, the fourth port 10 and the second port 1j face each other and are in communication with each other, and the fifth port 11 and the third port 1k face each other and are in communication with each other. Note that the first housing H1 and the second housing H2 may be one component rather than being separate bodies.

The inner diameter of the base end side, which is the opening side of the second valve hole 8, is larger than the inner diameter of the tip end side connected to the fourth port 10, and the second valve hole 8 forms a valve seat 14 for the second valve V2 at a step between the base end side and the tip end side, and accommodates a relief valve body 15 as a second valve body that seats and disengages from this valve seat 14. Furthermore, the second valve hole 8 accommodates a spring 16 that biases the relief valve body 15 toward the valve seat 14, and a spring retainer 17 is screwed to the left end side of the second valve hole 8. The second valve V2 is configured as a passive relief valve by the valve seat 14, the relief valve body 15, the spring 16, and the spring retainer 17, and is accommodated in the second valve hole 8 of the second housing H2. Therefore, when liquid is introduced from the outside through the fourth port 10 and the pressure inside the fourth port 10 exceeds the opening pressure of the second valve V2, the relief valve body 15 of the second valve V2 moves back from the valve seat 14 to open, connecting the fourth port 10 to the fifth port 11.

The spring bearing 17 has a cylindrical body 17a having a screw portion 17b and screwed to a screw portion 8a provided on the inner circumference of the opening end of the second valve hole 8 to close the opening of the second valve hole 8, and a guide portion 17c having an outer diameter smaller than that of the body 17a, which protrudes from the right end of the body 17a in FIG. 1 toward the relief valve body 15 and is inserted into the inner circumference of the spring 16, which is a coil spring. In the valve device V of this embodiment, the spring 16 is a coil spring as described above, and is sandwiched in a compressed state between the body 17a of the spring bearing 17 and the relief valve body 15. Therefore, the spring 16 is compressed in advance and applies an initial load to the relief valve body 15 toward the valve seat 14 to urge it. The spring 16 may also be composed of a spring other than a coil spring.

The left end of the spring bearing 17 is provided with an adjustment portion 17d formed as a linear recess into which the tip of a flathead screwdriver (not shown) can be inserted. Therefore, when the tip of the tool is inserted into the adjustment portion 17d and the tool is operated to rotate the spring bearing 17 in the circumferential direction, the spring bearing 17 moves along the axial direction of the second valve hole 8 and changes its mounting position relative to the second valve hole 8. When the mounting position of the spring bearing 17 relative to the second valve hole 8 is changed in this way, the compression amount of the spring 16 changes, and the initial load applied to the relief valve body 15 changes. When the force pushing the relief valve body 15 toward the spring bearing 17 side due to the action of the pressure received from the fourth port 10 side exceeds the initial load of the spring 16, the relief valve body 15 separates from the valve seat 14 and retreats toward the spring bearing 17 side within the second valve hole 8 until the force and the biasing force of the spring 16 are balanced. In other words, the second valve V2 opens due to the action of the pressure received from the fourth port 10 side. In this way, the initial load applied by the spring 16 to the relief valve body 15 sets the valve opening pressure when the second valve V2 as a relief valve opens. Therefore, when the tool is connected to the adjustment portion 17d and the spring receiver 17 is operated, the mounting position of the spring receiver 17 in the second valve hole 8 changes, so that the valve opening pressure of the second valve V2 can be adjusted by operating the spring receiver 17 with the tool. In this embodiment, the tool is a flat-head screwdriver, so the adjustment portion 17d of the spring receiver 17 is a linear groove that allows the flat-head screwdriver to be connected. However, if the tool is a hexagonal wrench, the adjustment portion 17d provided at the end of the spring receiver 17 may be a hexagonal hole, and if the tool is a Phillips screwdriver, the adjustment portion 17d may be a cross groove. In this way, the adjustment portion 17d provided at the end of the spring receiver 17 may be a groove or recess that matches the shape of the tool so that the corresponding tool can be connected and the spring receiver 17 can be rotated by operating the tool.

The first valve V1 is configured with a cylindrical first sleeve 2 and a cylindrical second sleeve 3 that are inserted in series into the first valve hole 1, a first spool 4 housed in the first sleeve 2, and a second spool 5 housed in the second sleeve 3.

The first sleeve 2 is formed into a stepped cylindrical shape with an outer diameter smaller at the tip end (the right end in FIG. 1) than at the rear end (the left end in FIG. 1). The first sleeve 2 also has an inner large diameter portion 2a on the inner circumference at the tip end, an inner small diameter portion 2b on the inner circumference at the rear end that is smaller in diameter than the inner large diameter portion 2a, a through hole 2c that opens from the outer circumference and leads to the inner large diameter portion 2a, a through hole 2d that opens from the outer circumference and leads to the inner small diameter portion 2b, and a through hole 2f that opens from the rear end and opens into a step 2e formed between the inner large diameter portion 2a and the inner small diameter portion 2b.

The first sleeve 2 thus constructed is inserted into the first valve hole 1 of the first housing H1 from the tip side, which has a small outer diameter, and the small diameter portion is fitted into the tip portion 1e and the large diameter portion is fitted into the middle portion 1f of the first housing H1, and is accommodated in the sleeve accommodation portion 1b of the first valve hole 1. In addition, the through hole 2c faces the first port 1i provided in the first housing H1 and communicates with it, and the through hole 2d faces the second port 1j provided in the first housing H1 and communicates with the fourth port 10 via the second port 1j.

The second sleeve 3 is tubular with a step, with the outer diameter at the tip end (the right end in FIG. 1) being smaller than the outer diameter at the rear end (the left end in FIG. 1). The inner circumference of the second sleeve 3 is provided with an inner large diameter portion 3a, the inner circumference of which is large, midway. Furthermore, the second sleeve 3 is provided with a through hole 3b that opens from the outer circumference and leads to the inner large diameter portion 3a.

The second sleeve 3 thus constructed is inserted into the first valve hole 1 of the first housing H1 from the tip side, where the outer circumference is small diameter, and the small diameter portion is fitted into the middle portion 1f of the first housing H1, and the large diameter portion is fitted into the rear end portion 1g of the first housing H1, and is accommodated in the sleeve accommodation portion 1b of the first valve hole 1. In addition, the through hole 3b faces the third port 1k provided in the first housing H1, and is connected to the fifth port 11 via the third port 1k.

The recess 3c provided on the right end side of the second sleeve 3 in FIG. 1 faces the through hole 2f that opens at the rear end, which is the left end in FIG. 1, of the first sleeve 2, and communicates with the large inner diameter portion 2a inside the first sleeve 2 via the through hole 2f.

As shown in Figs. 1 and 3, the plate 6 has an annular fitting portion 6a with a threaded portion on its inner circumference, and a flange-shaped convex plate portion 6b provided on the outer circumference of the rear end of the fitting portion 6a, which is the left end in Fig. 1. When the plate 6 is attached to the first housing H1, it closes the opening of the first valve hole 1 and a part of the opening of the second valve hole 8.

Specifically, the plate 6 is fastened to the first housing H1 by a bolt B inserted through the plate portion 6b, with the fitting portion 6a fitted into the plate insertion portion 1c of the first housing H1 and the plate portion 6b abutting against the left end face of the first housing H1 in FIG. 1, as shown in FIG. 3.

The plate 6 is then positioned in the axial direction by the abutment of the plate portion 6b against the rear end face, which is the left end face in FIG. 1, of the first housing H1, and is attached to the open end of the first valve hole 1 of the housing H. The end face at the right end in FIG. 1 of the fitting portion 6a of the plate 6 faces the rear end face of the second sleeve 3, and when the plate 6 is attached to the housing H, it functions as a retainer for the first sleeve 2 and second sleeve 3 that constitute the first valve V1 housed in the first valve hole 1.

Furthermore, the plate portion 6b has a protrusion protruding toward the opening end side of the left end of the second valve hole 8 in FIG. 1, and the tip side of the protrusion is adapted to block a part of the second valve hole 8. Specifically, the plate 6 has a semicircular notch 6c at a location (tip of the protrusion) corresponding to the second valve hole 8 of the plate portion 6b, and when fixed with the bolt B of the housing H as shown in FIG. 3, it blocks a part of the opening of the second valve hole 8 and makes the periphery of the notch 6c of the plate portion 6b face the spring bearing 17. In this way, when the plate 6 faces the spring bearing 17 in the axial direction of the second valve hole 8, the notch 6c becomes a relief that allows the connection of a tool to the adjustment portion 17d of the spring bearing 17, and while the plate 6 blocks a part of the second valve hole 8, it does not prevent easy connection of the tool to the adjustment portion 17d. Therefore, the plate 6 can prevent the spring receiver 17 from coming out of the second valve hole 8, does not prevent the spring receiver 17 from being connected to the adjustment part 17d with a tool, and allows the spring receiver 17 to be rotated using a tool. The shape of the notch 6c is not limited to a semicircular shape as long as it can prevent the spring receiver 17 from coming out of the second valve hole 8 and allows the tool to be connected to the adjustment part 17d. However, if the notch 6c is semicircular, the adjustment part 17d of the spring receiver 17 can be exposed to a large extent, making it easier to connect the adjustment part 17d with a tool and to rotate the spring receiver 17.

In addition, in order to prevent the spring receiver 17 from coming off from the second valve hole 8, the plate 6 needs only to be able to allow the connection of a tool to the adjustment portion 17d of the spring receiver 17 while facing a part of the spring receiver 17 in the axial direction of the second valve hole 8. Therefore, as shown in FIG. 4, a hole 6d that is smaller in diameter than the inner diameter of the second valve hole 8 and allows the insertion of a tool may be provided in the plate 6, and the periphery of the hole 6d of the plate portion 6b may be made to face the spring receiver 17, or as shown in FIG. 5, an end of the plate 6 may be made to face a portion avoiding the center portion of the spring receiver 17 in the axial direction of the second valve hole 8 to prevent the spring receiver 17 from falling off while allowing the connection to the adjustment portion 17d with a tool. If the plate 6 faces a position that avoids the center portion of the spring receiver 17, the tool can be connected to the center portion of the spring receiver 17 when the tool is connected to the adjustment portion 17d, making it easier to rotate the spring receiver 17. Also, as described above, the overall shape of the plate portion 6b is convex, but it can be changed as desired as long as it has a shape that can block part of the second valve hole 8.

In addition, in this example, when the plate 6 is axially positioned and attached to the housing H, the total axial length of the first sleeve 2 and the second sleeve 3 is set to be shorter than the axial length from the end face of the right end of the plate 6 in FIG. 1 to the step 1h that faces the tip end face of the first sleeve 2 in the first valve hole 1. Therefore, even when the plate 6 is attached to the housing H, the first sleeve 2 and the second sleeve 3 are not clamped in a compressed state between the plate 6 and the step 1h, and the first sleeve 2 and the second sleeve 3 are not subjected to axial force from the plate 6. The total axial length of the first sleeve 2 and the second sleeve 3 may be set to be equal to the axial length from the end face of the right end of the plate 6 in FIG. 1 to the step 1h that faces the tip end face of the first sleeve 2 in the first valve hole 1. Even in this way, the first sleeve 2 and the second sleeve 3 are not subjected to axial force from the plate 6.

Since the plate 6 only needs to be positioned in the axial direction and attached to the housing H, for example, the fitting portion 6a and the plate insertion portion 1c may be provided with threaded grooves and the two may be screwed together. In this example, a step 1m is provided between the plate insertion portion 1c and the sleeve accommodating portion 1b, so the right end of the fitting portion 6a in FIG. 1 may be brought into contact with the step 1m to position the plate 6 in the axial direction relative to the housing H. If a threaded groove is formed in the plate insertion portion 1c and the plate 6 is screwed to the housing H, the nominal diameter may increase, which may result in the outer shape (external shape) of the housing H becoming larger. In response to this, the plate 6 is provided with plate portion 6b and bolted to the housing H, which avoids the outer dimensions of the housing H becoming larger.

The first spool 4 is housed within the first sleeve 2 so as to be freely movable in the axial direction, and the movement is guided by the first sleeve 2. In detail, the first spool 4 has a sliding shaft portion 4a which is slidably inserted into the small diameter inner portion 2b of the first sleeve 2, a small diameter shaft portion 4b which extends rightward from the right end of the sliding shaft portion 4a in FIG. 1, and a truncated cone-shaped valve portion 4c provided at the right end of the small diameter shaft portion 4b in FIG. 1.

The sliding shaft portion 4a has an outer diameter larger than that of the small diameter shaft portion 4b, and is in sliding contact with the inner small diameter portion 2b of the first sleeve 2, and the first sleeve 2 guides the axial movement of the first spool 4 without axial wobble. The small diameter shaft portion 4b has an outer diameter smaller than the inner diameter of the inner small diameter portion 2b, and faces the through hole 2d provided in the first sleeve 2. In addition, the first spool 4 moves axially relative to the first sleeve 2, but the sliding shaft portion 4a does not completely block the opening of the through hole 2d.

The valve portion 4c has an outer diameter larger than the inner diameter of the inner small diameter portion 2b, and the inner peripheral edge of the step portion 2e serves as a valve seat 2g, so that the valve can be seated on and removed from the valve seat 2g by axial movement of the first spool 4.

A bottomed, cylindrical spring receiver 7 is attached to spring receiver mounting portion 1a in first valve hole 1 of first housing H1. Spring receiver 7 is cylindrical with a bottom and has a threaded portion 7a on its outer periphery, which can be screwed into threaded portion 1d in first valve hole 1 of first housing H1 to be attached to housing H. A retaining ring 19 screwed to the right end of first housing H1 in FIG. 1 prevents spring receiver 7 from falling out of first valve hole 1.

A spring S is interposed between the spring retainer 7 and the right end of the valve portion 4c of the first spool 4 in FIG. 1, and the biasing force of the spring S biases the first spool 4 in the direction in which the valve portion 4c seats on the valve seat 2g. In this way, the variable relief valve Vv is composed of the first spool 4 with the valve portion 4c, the first sleeve 2 with the valve seat 2g, and the spring S. When no external force is acting on the first spool 4 other than the spring S, the valve portion 4c is pressed against the valve seat 2g to close, and the opening pressure of the variable relief valve Vv becomes maximum, and a thrust is applied that pushes the first spool 4 in the opposite direction against the biasing force of the spring S. Adjusting this thrust adjusts the pressing force of the valve portion 4c against the valve seat 2g, and the opening pressure of the variable relief valve Vv can be adjusted.

When the variable relief valve Vv opens, the damping force adjustment flow path, which is composed of the fourth port 10, the second port 1j, the through hole 2d, the inside of the large diameter inner circumference portion 2a, the through hole 2c, and the first port 1i, is in a connected state. On the other hand, when the valve portion 4c is seated on the valve seat 2g and the variable relief valve Vv is closed, the connection between the through hole 2d and the large diameter inner circumference portion 2a is severed, and the damping force adjustment flow path is blocked.

A valve body side spring bearing 24 is interposed between the spring S and the first spool 4. In this example, the spring S is a coil spring, and the right end of the valve body side spring bearing 24 in FIG. 1 is loosely fitted on the inner circumference of the spring S, so that the valve body side spring bearing 24 can absorb any misalignment between the axis of the spring S and the first spool 4. As a result, the biasing force of the spring S acts on the first spool 4 without bias in the radial direction, so that the valve opening pressure of the first spool 4 is stable and without variation.

The second spool 5 is housed in the second sleeve 3 so as to be freely movable in the axial direction, and the movement is guided by the second sleeve 3, and the right end in FIG. 1 can abut against the left end in FIG. 1 of the first spool 4. In detail, the second spool 5 has a sliding shaft portion 5a slidably inserted into the second sleeve 3, a cylindrical valve portion 5b extending rightward from the right end in FIG. 1 of the sliding shaft portion 5a, and a protrusion 5c provided at the right end in FIG. 1 of the valve portion 5b that protrudes in the axial direction.

The sliding shaft portion 5a is in sliding contact with the inner circumference of the second sleeve 3, except for the inner large diameter portion 3a, and the second sleeve 3 guides the axial movement of the second spool 5 without axial wobble.

The valve portion 5b has an outer diameter set to a diameter that slides against the inner circumference of the second sleeve 3, and when positioned to the right of the inner large diameter portion 3a, it cuts off communication between the flow path formed by the through hole 3b provided in the second sleeve 3 and the inside of the second sleeve 3.

A flange 5d is provided at the rear end of the sliding shaft portion 5a, which is the left end in FIG. 1, and a coil spring 25 is interposed between the right end of the flange 5d in FIG. 1 and the left end of the second sleeve 3 in FIG. 1. The second spool 5 is biased leftward in FIG. 1 by this coil spring 25. When no external force acts other than the biasing force of the coil spring 25, the second spool 5 communicates with the flow path consisting of the through hole 3b and the inside of the second sleeve 3 when the valve portion 5b is positioned in the large inner diameter portion 3a, as shown in FIG. 1.

Furthermore, a solenoid Sol is attached to the left side of the plate 6 in FIG. 1, and when electricity is applied to the solenoid Sol, a thrust force in the right direction in FIG. 1 is applied to the second spool 5 that abuts against the plunger P of the solenoid Sol. Although not shown in detail, the solenoid Sol is equipped with a cylindrical fixed core 26, a plunger P that is inserted inside the fixed core 26 so as to be freely movable in the axial direction, a second fixed core (not shown) that has a cylindrical portion that is arranged on the outer periphery of the plunger P and faces the fixed core 26 in the axial direction, and a coil (not shown) that is provided on the outer periphery of the fixed core 26 and the second fixed core, and generates a thrust that urges the plunger P toward the right in FIG. 1 when electricity is applied to the coil. In addition, the outer periphery of the right end of the fixed core 26 in FIG. 1 is equipped with a screw portion 26a that is screwed into a screw portion provided on the inner periphery of the fitting portion 6a of the plate 6. Therefore, the solenoid Sol is fixed to the housing H by screwing the fixed core 26 to the plate 6. When the solenoid Sol is fixed to the first housing H1 in this manner, the plunger P abuts against the left end of the second spool 5 in FIG. 1, so that the solenoid Sol can apply thrust to the second spool 5 via the plunger P, which is attracted to the fixed core 26 by energizing the coil.

In addition, the thrust applied to the second spool 5 can be adjusted by adjusting the amount of current passing through the solenoid Sol. This thrust applies a force to the second spool 5 in a direction that opposes the coil spring 25, so that the second spool 5 can be moved to a position where the valve portion 5b enters the inner large diameter portion 3a against the biasing force of the coil spring 25. Therefore, depending on whether or not current is passed through the solenoid Sol, the second spool 5 can be moved in the axial direction to connect or disconnect the flow path. In this way, the second sleeve 3 and the second spool 5 constitute an opening and closing valve Ov that opens and closes the flow path, and this opening and closing valve Ov is an electromagnetic opening and closing valve that opens and closes the flow path by passing current through the solenoid Sol.

When the on-off valve Ov is opened, the bypass flow path consisting of the fourth port 10, the second valve hole 8, the fifth port 11, the third port 1k, the through hole 3b, the recess 3c, the through hole 2f, the large inner diameter portion 2a, the through hole 2c, and the first port 1i is opened. When the bypass flow path is opened, the second valve V2 provided in the second valve hole 8 is also opened, and when the pressure introduced from the fourth port 10 reaches the opening pressure of the second valve V2, the second valve V2 opens, allowing pressure to escape through the bypass flow path. When the on-off valve Ov is closed, the flow path consisting of the through hole 3b and the inside of the second sleeve 3 is disconnected, and the bypass flow path is blocked.

The thrust applied to the second spool 5 can be adjusted by the amount of current flowing through the solenoid Sol. When the second spool 5 closes the flow path and the second spool 5 is brought into contact with the first spool 4, the thrust of the solenoid Sol can also be transmitted to the first spool 4 via the second spool 5.

In this way, the thrust of the solenoid Sol can be applied to the first spool 4 in a direction opposing the spring S, and the opening pressure of the variable relief valve Vv can be adjusted by adjusting the amount of current flowing through the solenoid Sol to adjust the thrust applied to the first spool 4.

As shown in FIG. 2, the damper D to which the valve device V configured in this manner is applied is configured with a cylinder 31, a piston 32 that is inserted movably into the cylinder 31 and divides the cylinder 31 into a rod side chamber R1 and a piston side chamber R2, a rod 33 that is inserted into the cylinder 31 and connected to the piston 32, a tank T, a first opening/closing valve 35 provided in the middle of a first passage 34 that connects the rod side chamber R1 and the piston side chamber R2, a second opening/closing valve 37 provided in the middle of a second passage 36 that connects the piston side chamber R2 and the tank T, a damping flow path CP that connects the rod side chamber R1 and the tank T, a straightening passage 38 that allows only the flow of hydraulic oil from the piston side chamber R2 to the rod side chamber R1, and a suction passage 39 that allows only the flow of hydraulic oil from the tank T to the piston side chamber R2.

The valve device V is provided in the middle of the damping passage CP, specifically, the fourth port 10 is connected to the rod side chamber R1 side and the first port 1i is connected to the tank T side, and is provided in the damping passage CP.

When the damper D configured in this manner contracts with the first passage 34 open by the first on-off valve 35 and the second on-off valve 37 closed, the rod 33 enters the cylinder 31 and displaces a volume of liquid that is pushed out from the cylinder 31 into the damping flow path CP. Under these circumstances, when the solenoid Sol can be energized and the on-off valve Ov is closed and the opening pressure of the variable relief valve Vv is adjusted, the pressure inside the cylinder 31 is controlled to the opening pressure of the variable relief valve Vv, and the damper D exerts a damping force that prevents contraction. The damping force that prevents contraction of the damper D can be adjusted by adjusting the opening pressure of the variable relief valve Vv.

When the damper D extends with the first passage 34 open by the first valve 35 and the second valve 37 closed, the volume of liquid that the rod 33 withdraws from the cylinder 31 is supplied from the tank T via the suction passage 39. In this case, the pressure in the cylinder 31 is nearly equal to the tank pressure, so the damper D extends with almost no resistance. Therefore, when the first valve 35 is opened and the second valve 37 is closed, the damper D functions as a one-sided damper that exerts a damping force only during contraction.

On the other hand, when the damper D is extended with the first on-off valve 35 closed and the second on-off valve 37 opening the second passage 36, the liquid equivalent to the volume of the rod 33 withdrawn from the cylinder 31 is pushed from the rod side chamber R1 to the damping flow path CP. Liquid is supplied from the tank T to the expanding piston side chamber R2. Under these circumstances, when the solenoid Sol can be energized and the on-off valve Ov is closed and the opening pressure of the variable relief valve Vv is adjusted, the pressure in the rod side chamber R1 is controlled to the opening pressure of the variable relief valve Vv, and the damper D exerts a damping force that prevents extension. The damping force that prevents extension of the damper D can be adjusted by adjusting the opening pressure of the variable relief valve Vv.

When the damper D is contracted with the first opening/closing valve 35 closed and the second opening/closing valve 37 opening the second passage 36, the volume of liquid that the rod 33 enters into the cylinder 31 is discharged from the cylinder 31 through the second passage 36 to the tank T. In this case, the pressure inside the cylinder 31 becomes almost equal to the tank pressure, so the damper D contracts with almost no resistance. Therefore, when the first opening/closing valve 35 is closed and the second opening/closing valve 37 is opened, the damper D functions as a one-sided damper that exerts a damping force only during extension.

When the first on-off valve 35 and the second on-off valve 37 are both closed, the rod side chamber R1, the piston side chamber R2, and the tank T are connected in a chain through the rectification passage 38, the suction passage 39, and the damping passage CP. In this state, if the solenoid Sol can be energized, when the damper D is expanded or contracted by an external force, the pressure in the rod side chamber R1 can be controlled by the variable relief valve Vv, and the damper D can exert a damping force according to the amount of electricity supplied to the solenoid Sol. In other words, in this case, the damping force of the damper D can be controlled. Also, when the solenoid Sol cannot be energized or is not energized, the opening and closing valve Ov opens, so the bypass passage is effective. In this case, when the damper D is expanded or contracted by an external force, the pressure in the rod side chamber R1 is controlled to be the opening pressure of the second valve V2 as a relief valve, and the damper D exerts a damping force according to the setting of the second valve V2. Therefore, in this case, damper D functions as a passive damper.

In this way, the valve device V can function as a damping force generator when applied to the damper D. Although not shown, if an actuator is constructed by providing a pump that supplies liquid to the rod side chamber R1 in addition to the configuration of the damper D and the valve device V, the thrust of the actuator can also be adjusted by adjusting the valve opening pressure with the variable relief valve Vv.

The valve device V of this embodiment includes a housing H having a first valve hole 1 and a second valve hole 8 that open in parallel in the same direction from the outside, a first valve V1 having first and second spools (first valve bodies) 4, 5 that are inserted into the first valve hole 1 and driven by a solenoid Sol, a second valve V2 that is inserted into the second valve hole 8, and a plate 6 that is connected to the solenoid Sol and fastened to the housing H to block a portion of the first valve hole 1 and the second valve hole 8. The valve V2 includes a relief valve body (second valve body) 15 inserted into the second valve hole 8 so as to be movable in the axial direction of the second valve hole 8, a spring bearing 17 screwed to the open end side of the second valve hole 8 to close the second valve hole 8 and having an adjustment portion 17d at its end that allows rotational operation with a tool from the outside, and a spring 16 interposed between the relief valve body (second valve body) 15 and the spring bearing 17, and the plate 6 faces the end of the spring bearing 17 in the axial direction of the second valve hole 8 while allowing connection to the adjustment portion 17d of the tool. In the valve device V configured in this manner, the plate 6 that prevents the first valve V1 accommodated in the first valve hole 1 from falling out faces a part of the spring bearing 17 in the second valve V2 accommodated in the second valve hole 8 arranged in parallel to the first valve hole 1, thereby preventing the second valve V2 from falling out of the second valve hole 8 and also allowing rotational operation of the spring bearing 17 with the use of a tool. Therefore, with the valve device V of this embodiment, not only is it possible to reliably prevent the spring bearing 17 from falling off the housing H, eliminating the risk of liquid leakage, but it also makes it possible to adjust the valve inside the second valve hole 8.

The plate 6 in the valve device V is preferably arranged to face the second valve hole 8 in the axial direction at a position that avoids the center of the spring bearing 17. With a valve device V configured in this way, when a tool is connected to the adjustment part 17d, it is possible to connect the tool to the center of the spring bearing 17, making it easy to rotate the spring bearing 17.

In the valve device V of this embodiment, the plate 6 has a semicircular notch 6c, and the periphery of the notch 6c faces the spring bearing 17. With the valve device V configured in this manner, the notch 6c serves as a relief that allows a tool to be connected to the adjustment portion 17d of the spring bearing 17, and while the plate 6 blocks a portion of the second valve hole 8, it does not prevent easy connection of the tool to the adjustment portion 17d. In addition, because the shape of the notch 6c is semicircular, the adjustment portion 17d of the spring bearing 17 can be largely exposed, making it easier to connect the adjustment portion 17d of the tool and to rotate the spring bearing 17.

In addition, the valve device V in this embodiment includes a housing H having a first valve hole 1, a first sleeve 2 and a second sleeve 3 inserted in series into the first valve hole 1, a first spool 4 housed in the first sleeve 2, a second spool 5 housed in the second sleeve 3, and a plate 6 attached to the open end of the housing H. When the valve device V is configured in this manner, the plate 6 is positioned in the axial direction by the housing H, so that the first sleeve 2 and the second sleeve 3 housed in the first valve hole 1 can be prevented from coming off without applying an axial tensile load or compressive load to them. In addition, since the second sleeve 3 is not screwed into the housing H, it is not necessary to apply torque to the first sleeve 2 and the second sleeve 3. Therefore, no distortion occurs in the inner peripheral shape of the first sleeve 2 and the second sleeve 3 in which the first spool 4 and the second spool 5 are housed. This eliminates the need for highly accurate management of the dimensions of the first sleeve 2, the second sleeve 3, the plate 6, and the housing H, and ensures smooth axial movement of the first spool 4 and the second spool 5 without the need to shape the inner circumference of the first sleeve 2 and the second sleeve 3. As described above, the valve device V of the present invention is easy to process and allows the first spool 4 and the second spool 5 to operate smoothly.

In addition, in the valve device V of this example, the total axial length of the first sleeve 2 and the second sleeve 3 is shorter than the axial length from the step 1h of the housing H to the end face of the plate 6. Therefore, even when the plate 6 is attached to the housing H, the first sleeve 2 and the second sleeve 3 are not sandwiched in a compressed state between the plate 6 and the step 1h, and a state in which no axial force acts on the first sleeve 2 and the second sleeve 3 can be reliably achieved. In addition, dimensional control of the first sleeve 2, second sleeve 3, plate 6, and housing H is also easier.

Furthermore, in the valve device V of this example, the plate 6 has a plate portion 6b on its outer periphery, and is positioned by abutting the plate portion 6b against the end face of the housing H. In this way, the plate 6 is positioned by the housing H with a simple structure, and the axial load on the first sleeve 2 and second sleeve 3 is reliably prevented.

In addition, in the valve device V of this example, the plate 6 is fixed to the housing H by bolting the plate portion 6b of the plate 6 to the housing H. Therefore, there is no need to rotate the plate 6 when attaching it to the housing H, so even if the plate 6 comes into contact with the second sleeve 3, there is no need to worry about torque acting on the first sleeve 2 and the second sleeve 3. This reliably prevents distortion of the inner circumferential shapes of the first sleeve 2 and the second sleeve 3 due to torque load.

Furthermore, in the valve device V of this example, the first valve V1 includes an opening/closing valve Ov composed of a second spool 5 and a second sleeve 3, and a variable relief valve Vv composed of a first spool 4 and a first sleeve 2, and includes a solenoid Sol that applies thrust to the first spool 4 via the second spool 5. By configuring the valve device V in this way, the opening and closing of the opening/closing valve Ov and the adjustment of the opening pressure of the variable relief valve Vv can be performed with a single solenoid Sol. Note that the first valve V1 may be a valve other than that described above.

Also, the opening and closing valve Ov may be opened when the solenoid Sol is not energized, and closed when the solenoid Sol is energized, and the opening pressure of the variable relief valve Vv may be adjusted, and a second valve V2 may be provided in series with the opening and closing valve Ov. In this case, if the valve device V is applied to the damper D or actuator, the damper D or actuator can be expected to exert a damping force as a damper even in the event of a failure.

Although the preferred embodiment of the present invention has been described in detail above, modifications, variations, and changes are possible without departing from the scope of the claims.

1: First valve hole, 4: First spool (first valve body), 5: Second spool (first valve body), 6: Plate, 6c: Notch, 8: Second valve hole, 15: Relief valve body (second valve body), 16: Spring, 17: Spring support, 17d: Adjustment part, H: Housing, Sol: Solenoid, V: Valve device, V1: First valve, V2: Second valve

Claims (2)

a housing having a first valve hole and a second valve hole opening in parallel in the same direction from the outside;
a first valve having a first valve body inserted into the first valve hole and actuated by a solenoid; and a second valve inserted into the second valve hole.
a plate connected to the solenoid and fastened to the housing to close a portion of the first valve hole and a portion of the second valve hole,
The second valve is
a second valve body inserted into the second valve hole so as to be movable in an axial direction of the second valve hole;
a spring bearing having an adjustment portion at an end thereof that is screwed into an open end side of the second valve hole to close the second valve hole and that can be rotated by an external tool;
a spring interposed between the second valve body and the spring bearing,
The plate has a semicircular notch, the periphery of the notch faces the spring bearing, and faces an end of the spring bearing in the axial direction of the second valve hole while allowing connection of the tool to the adjustment portion. The valve device according to claim 1 , wherein the plate faces a position that avoids a central portion of the spring bearing in the axial direction of the second valve hole.

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