JP6204703B2 - Solenoid valve and shock absorber - Google Patents

Description

  The present invention relates to improvements in solenoid valves and shock absorbers.

  Conventionally, as a damping force adjustment valve that can adjust the damping force of a shock absorber mounted on a vehicle while traveling, a spool valve is inserted into the inner periphery of a cylindrical piston rod, and this spool valve is driven by a solenoid. There is something to do.

  Specifically, the damping force adjusting valve has a cylindrical piston rod whose tip faces the pressure side chamber of the shock absorber, and is provided with a port that opens from the position facing the extension side chamber, and extends through this port and the inside of the piston rod. The side chamber and the pressure side chamber are communicated with each other, and a cylindrical spool valve having an orifice hole that can face the port is inserted into the piston rod. The damping force adjustment valve adjusts the damping force generated by the shock absorber by changing the lap area of the port and the orifice hole by driving the spool valve in the axial direction within the piston rod with a solenoid. (For example, refer to Patent Document 1).

JP 2012-149719 A

  By the way, when the hydraulic oil passes through the orifice hole, the faster the hydraulic oil flows, the lower the pressure. Here, when the lap area of the port and orifice hole is reduced with the spool valve, the spool valve is moved so that the side of the spool valve faces the port, but if the lap area is reduced, the flow rate must change. As a result, the flow of hydraulic oil passing through the orifice hole becomes faster. If the lap area of the orifice hole and the port end are reduced to such an extent that they wrap, the flow of hydraulic oil passing through the orifice hole becomes faster at the end of the orifice hole, resulting in a pressure drop. Since the pressure acting on the entire circumference of the wall surface of the orifice hole is not uniform, a force in the direction of reducing the lap area (valve closing direction) acts on the spool valve.

  On the other hand, the solenoid is provided with a spring for urging the spool valve, and drives the spool valve to a position where the suction force generated when energized and the urging force of the spring are balanced. For this reason, when considering driving the spool valve with a solenoid, when the lap area between the port and the orifice hole is reduced, if the flow velocity flowing through them increases, the pressure drop due to the liquid flow causes the spool valve to Since the force in the closing direction increases, the position of the spool valve deviates from the target position, and there is a problem that the desired damping force cannot be exhibited.

  As a countermeasure against such a problem, the set load, which is a load applied in advance to the spring, is increased so that the spool valve is pressed in the valve opening direction with a large spring force in advance, and the valve closing direction acting on the spool valve described above is increased. It is conceivable to counteract the force, but in this case, even if current is applied to the solenoid, the dead zone where the spool valve is restrained by the spring force and becomes inoperable increases, especially in the low pressure range where the flow rate is low. Will be damaged.

  Accordingly, the present invention has been made to solve the above-described problems, and an object of the present invention is to provide a solenoid valve and a shock absorber capable of exhibiting a stable damping force without impairing the flow rate controllability. It is to be.

To achieve the above object, problem-solving means of the present invention includes a housing having a downstream port leading to the upstream passage and the hollow portion communicates with the hollow portion and the hollow portion, the inner and outer a cylindrical A spool valve having a communicating spool port and slidably inserted in the hollow portion in the axial direction; and a solenoid for driving the spool valve in the axial direction, the spool port and the inside of the spool valve being interposed the upstream passage a communicable to said downstream port, a adjustable solenoid valve for communicating the degree of the spool port and the downstream port by driving the spool valve Te, the upstream of the spool valve A throttle valve is provided that reduces the pressure upstream of the spool valve and reduces the force pushing the spool valve in the valve closing direction.

  In the case of a solenoid valve, the liquid passing through the solenoid valve passes through a throttle valve arranged upstream of the spool valve, so that the pressure upstream of the spool valve can be reduced and compared with the case where no throttle valve is provided. Thus, the force for pushing the spool valve in the valve closing direction is reduced. Thus, since the force that pushes the spool valve in the valve closing direction can be reduced by passing through the spool valve, the set load applied in advance to the spring that biases the spool valve is increased with respect to the force. There is no need to compete.

  Therefore, according to the solenoid valve and the shock absorber of the present invention, a stable damping force can be exhibited without impairing the flow rate controllability.

It is sectional drawing of the buffer with which the solenoid valve in one Embodiment was applied. It is an expanded sectional view of the solenoid valve in one embodiment. It is a figure explaining the pressure distribution in a spool port when not providing a throttle valve. It is a figure explaining the pressure distribution in the spool port of the solenoid valve in one embodiment. It is sectional drawing of the solenoid valve in one modification of one Embodiment.

  The present invention will be described below based on the embodiments shown in the drawings. As shown in FIGS. 1 and 2, the solenoid valve 1 in one embodiment includes a hollow portion C, an upstream passage P communicating with the hollow portion C, and a downstream port opening from the outside and communicating with the hollow portion C. A housing E having 9b, a spool valve 7 inserted into the hollow portion C so as to be movable in the axial direction, a solenoid 8 for driving the spool valve 7 in the axial direction, and a throttle valve provided upstream of the spool valve 7. O is comprised.

  In this embodiment, the solenoid valve 1 is applied to the shock absorber D, and can adjust the damping force generated when the shock absorber D extends. Specifically, the shock absorber D is divided into a cylinder 2 and an extension side chamber R1 and a pressure side chamber R2 which are slidably inserted into the cylinder 2 and filled with a liquid such as hydraulic oil. A piston 3; a piston rod 4 inserted into the cylinder 2 and connected to the piston 3; and a damping force adjusting passage 5 provided in the piston rod 4 and allowing passage of liquid only when the shock absorber D is extended. The solenoid valve 1 is provided in the damping force adjusting passage 5 and adjusts the damping force generated by the shock absorber D.

  In this example, the shock absorber D includes a vehicle body side tube 10 that connects the piston rod 4 to a vehicle body (not shown) of a saddle vehicle such as a two-wheeled vehicle so as to face the saddle vehicle, and a saddle vehicle (not shown). It is accommodated in a front fork F that is composed of an axle side tube 11 that is connected to the axle and is slidably inserted into the vehicle body side tube 10. More specifically, in the shock absorber D, the piston rod 4 is connected to the vehicle body side tube 10 via the housing main body 6, the cylinder 2 is connected to the axle side tube 11, and the vehicle body side tube 10 and the axle side tube 11 are connected. It is accommodated in the space L which is in the front fork F closed by the vehicle body side tube 10 and the axle side tube 11 while being interposed therebetween. In the present embodiment, the front fork F is an inverted front fork that inserts the axle tube 11 into the vehicle body side tube 10, but on the contrary, the vehicle body side tube 10 is inserted into the axle tube 11. It may be an upright front fork.

  Further, a suspension spring 12 is interposed between the piston rod 4 and the cylinder 2 of the shock absorber D. The suspension spring 12 connects the vehicle body side tube 10 and the axle side tube 11 via the shock absorber D. The elastic force is exerted in the direction of separating, that is, the direction of extending the shock absorber D, and the suspension spring 12 elastically supports the vehicle body of the straddle vehicle not shown.

  As shown in FIG. 1, the shock absorber D includes a cylinder 2 connected to the axle-side tube 11, and an extension side chamber R <b> 1 that is slidably inserted into the cylinder 2 and is two working chambers inside the cylinder 2. The piston 3 partitioned into the pressure side chamber R2, the piston rod 4 having one end connected to the piston 3 and the other end connected to the vehicle body side tube 10, and the extension side chamber R1 and the pressure side chamber R2 provided in the piston 3 A damping passage 13 that communicates and provides resistance to the flow of liquid that passes through, a pressure-side damping passage 15 that is provided at the lower end of the cylinder 2 and that provides resistance to the flow of liquid from the pressure-side chamber R2 to the reservoir R, and a pressure-side chamber from the reservoir R And a bottom member 14 having a suction passage 16 that allows only the flow of liquid toward R2, and the expansion side chamber R1 and the pressure side chamber R2 have a liquid such as hydraulic oil as a liquid. There is filled, it is in the reservoir R liquids and gases are filled.

  In more detail, the cylinder 2 is being fixed to the bottom part of the axle side tube 11 formed in the bottomed cylinder shape via the bottom member 14 fitted by the lower end. A rod guide 17 is provided at the upper end of the cylinder 2 to support the piston rod 4 so as to be slidable. The piston rod 4 includes a piston rod body 4a having a hole 4b penetrating in the vertical direction in FIG. 1 along the axial direction, and a piston connecting portion that is fixed to the lower end of the piston rod body 4a in FIG. 4c, and the tip that is the upper end in FIG. 1 is fixed to the upper end of the vehicle body side tube 10 via the housing E that houses the spool valve 7 in the solenoid valve 1. The piston connecting portion 4c includes a communication passage 4d that communicates the hole 4b and the extension side chamber R1, and a check valve that is provided in the middle of the communication passage 4d and that allows only a liquid flow from the extension side chamber R1 toward the hole 4b. 4e, and the annular piston 3 is fixed to the lower end in FIG. In this case, the damping force adjusting passage 5 is composed of a hole 4b and a communication passage 4d.

  A suspension spring 12 is interposed between the rod guide 17 and a cylindrical spring receiver 18 provided on the outer periphery of the housing body 6, and the shock absorber D is urged in the extension direction by the suspension spring 12, thereby The shock absorber D is also urged in the extending direction by the suspension spring 12.

  The piston 3 is fixed to the lower end in FIG. 1 of the piston rod 4, and the damping passage 13 provided in the piston 3 is provided in the middle of the passage 13a and the passage 13a that connects the extension side chamber R1 and the pressure side chamber R2. A damping valve 13b is provided to provide resistance to the flow of liquid passing therethrough. In this case, the damping valve 13b is a throttle valve or the like, and the damping passage 13 has a bidirectional flow of the liquid flowing from the expansion side chamber R1 to the compression side chamber R2 and the flow of the liquid from the compression side chamber R2 to the expansion side chamber R1. Although the flow is allowed, two or more passages are provided, and a damping valve that allows only the flow of the liquid from the extension side chamber R1 to the pressure side chamber R2 is provided in a part of the passages, and the pressure side is provided in the other passages. A damping valve that allows only the flow of liquid from the chamber R2 toward the extension side chamber R1 may be provided.

  The reservoir R is formed in the space L and outside the buffer D, and the reservoir R is filled with liquid and gas. The pressure-side damping passage 15 formed in the bottom member 14 resists the flow of the liquid passing through the passage 15a that connects the pressure-side chamber R2 and the reservoir R, and allowing only the flow of the liquid from the pressure-side chamber R2 to the reservoir R. And a one-way passage allowing only the flow of liquid from the pressure side chamber R2 to the reservoir R. On the other hand, the suction passage 16 formed in the bottom member 14 includes a passage 16a that connects the reservoir R and the pressure side chamber R2, and a check valve 16b that allows only the flow of liquid from the reservoir R to the pressure side chamber R2. This is a one-way passage that allows only the flow of liquid from the reservoir R to the pressure-side chamber R2 in the opposite direction to the pressure-side attenuation passage 15. In the shock absorber D, the pressure-side damping force can be generated by the damping valve 15b, so that a passage allowing only the liquid flow from the pressure-side chamber R2 to the extension-side chamber R1 is provided as described above. In this case, it is not necessary to provide a damping valve in the passage.

  Next, the solenoid valve 1 will be described. The solenoid valve 1 is connected to the damping force adjusting passage 5 described above, and includes a housing E having a hollow portion C and a spool valve 7 slidably inserted into the hollow portion C of the housing E. The solenoid valve 8 is configured to include a solenoid valve 8 that drives the spool valve 7 in the housing E and a throttle valve O, with the spool valve 7 as a movable iron core.

  The housing E includes a cylindrical housing main body 6 and a cylindrical valve sleeve 9 accommodated in the housing main body 6. As shown in FIGS. 1 and 2, the housing body 6 is in this case cylindrical and is formed with an inner diameter enlarged to accommodate the above-described valve sleeve 9 and spool valve 7 therein. 6a and a passage portion 6b which is provided on the inner periphery of the housing body 6 and which is provided at the distal end side which is the lower end in FIG. 2, an annular groove 6c provided in the inner periphery of the accommodating portion 6a along the circumferential direction, a discharge passage 6d that opens from the outer periphery and communicates with the annular groove 6c, and an inner periphery of the housing body 6 at the upper end in FIG. A solenoid mounting portion 6e having an inner diameter larger than that of the housing portion 6a provided at a rear end is provided.

Further, a screw hole portion 6f is provided on the lower inner periphery in FIG. 2 of the passage portion 6b of the housing body 6, and a screw portion 4f is provided on the outer periphery of the upper end of the piston rod 4, and the screw hole portion. A screw can be fastened while inserting the upper end of the piston rod 4 into 6f. That is, the hole 4b provided in the piston rod body 4a communicates with the housing body 6, and the housing body 6 communicates with the expansion side chamber R1 via the hole 4b and the communication passage 4d. Furthermore, in the case of this embodiment, a screw hole portion 6g that enables screwing of the plug 20 provided with an orifice as the throttle valve O is provided above the screw hole portion 6f of the passage portion 6b in FIG. Is provided. The plug 20 includes a throttle valve O formed by an orifice penetrating in the axial direction and a screw part on the outer periphery, and is screwed into the passage part 6 b of the housing body 6. In this embodiment, a nut 19 is screwed onto the screw portion 4f, and the upper end of the nut 19 in FIG. 2 is brought into contact with the lower end of the housing body 6 in FIG. It is considered that the screw hole 6f and the screw 4f are not loosened by being applied.

  Further, a screw portion 6 h is provided on the outer periphery of the upper end of the housing body 6 in FIG. 2, and the piston rod 4 is attached to the vehicle body side tube 10 by screwing the housing body 6 to the opening end of the vehicle body side tube 10. It can be connected.

  The valve sleeve 9 has a cylindrical shape and is provided with a hollow portion C on the inner periphery, an annular groove 9a provided along the circumferential direction of the hollow portion C, and a valve that opens from the outer periphery and communicates with the annular groove 9a. A downstream port 9b that communicates between the inside and the outside of the sleeve 9 and ring mounting grooves 9c and 9d that are annular grooves provided at positions on the outer periphery and sandwiching the downstream port 9b when viewed in the axial direction are configured. The outer diameter of the valve sleeve 9 is smaller than the inner diameter of the accommodating portion 6a of the housing body 6, and when the valve sleeve 9 is accommodated in the accommodating portion 6a, there is play, so that the valve sleeve 9 moves in the radial direction. Is possible. Further, elastic rings 25 and 26 are mounted in the ring mounting grooves 9 c and 9 d of the valve sleeve 9. In the case of this embodiment, the elastic rings 25 and 26 are, for example, O-rings formed of a resin material exhibiting elasticity and sealing properties such as rubber, and the outer diameter is the inner diameter of the accommodating portion 6a of the housing body 6 When the valve sleeve 9 is accommodated in the accommodating portion 6a of the housing body 6, the elastic rings 25 and 26 abut against the inner wall of the accommodating portion 6a, and the valve sleeve 9 is Is supported floating. That is, there is a gap between the valve sleeve 9 and the housing portion 6a of the housing body 6, the valve sleeve 9 is elastically supported by the elastic rings 25 and 26, and the valve sleeve 9 is radially arranged in the housing portion 6a. Is allowed to move to. Thus, when the valve sleeve 9 is accommodated in the accommodating portion 6a, the downstream port 9b communicates with the discharge passage 6d so as to face the annular groove 6c, and in the shock absorber D via the valve sleeve 9 and the downstream port 9b. The extension side chamber R1 and the reservoir R communicate with each other. In this case, the elastic rings 25 and 26 also function as seals and are disposed on both sides in the axial direction across the downstream port 9b. Therefore, the space between the valve sleeve 9 and the housing body 6 is sealed, and the liquid flows downstream. The passage from the extension side chamber R1 to the reservoir R through other than the port 9b is prevented. Further, since the elastic rings 25 and 26 only need to have elasticity, the elastic rings 25 and 26 may not exhibit the sealing function. In that case, since a separate seal is required, the sealing function is provided. It is possible to reduce the number of parts and the cost.

  When the housing E composed of the housing main body 6 and the valve sleeve 9 is connected to the piston rod 4 in this way, the hollow portion C in the valve sleeve 9 and the hole 4b of the piston rod 4 are connected coaxially and in series. The inner diameter of the portion C is set to be larger than the inner diameter of the spool valve 7 and communicates with the expansion side chamber R1 in the shock absorber D through the air hole 4b and the communication path 4d. The hollow portion C communicates with a reservoir R formed outside the shock absorber D through an annular groove 9a, a downstream port 9b, an annular groove 6c, and a discharge passage 6d. Therefore, in the case of this embodiment, the upstream passage P is formed by the passage portion 6b in the housing body 6 described above, and communicates the hollow portion C to the extension side chamber R1.

  Further, since the check valve 4e is provided upstream of the upstream passage P, the liquid flows through the upstream passage P only in the direction from the extension side chamber R1 to the reservoir R. The check valve that sets the upstream passage P to one-way is not provided in the piston connecting portion 4c but may be provided in another location. Specifically, for example, in the hole 4b of the piston rod body 4a. It may be provided, or may be provided at the opening end of the hole 4b at the upper end in FIG. 1 of the piston rod body 4a, or may be provided in the housing body 6.

  The spool valve 7 has a cylindrical shape and is slidably inserted into the valve sleeve 9. The spool valve 7 includes a spool port 7 a that opens from the side and communicates with the inside and outside of the spool valve 7. The inner diameter of the range where the spool port 7a is provided from the lower end, which is one end of the spool valve 7, may be made larger than the inner diameter outside the range, so that the thickness of the range is reduced. By doing so, the length of the spool port 7a can be shortened, and the force for pushing the spool valve 7 in the valve closing direction when the liquid flows through the spool port 7a can be reduced. That is, when the flow velocity of the liquid passing through the spool port 7a is increased, the pressure is reduced, and the pressure receiving area where the pressure in the spool port 7a moves the axial direction of the spool valve 7 is proportional to the length of the spool port 7a. Therefore, by shortening the length, it is possible to reduce the force for moving the spool valve 7 caused by the pressure drop caused by the increase in the flow velocity in the valve closing direction.

  When the spool valve 7 slides in the valve sleeve 9 and the spool port 7a faces the annular groove 9a, the spool port 7a and the downstream port 9b are in communication with each other and the solenoid valve 1 is opened, When the spool port 7a is not opposed to the annular groove 9a and the side surface of the spool valve 7 closes the annular groove 9a, the connection between the spool port 7a and the downstream port 9b is cut off, and the solenoid valve 1 is closed, and the spool port 7a is closed. The valve opening degree of the solenoid valve 1 can be adjusted by adjusting the degree of communication between 7a and the annular groove 9a.

  In this embodiment, since the annular groove 9a is provided, the downstream port 9b and the spool port 7a can communicate with each other even if the spool valve 7 rotates in the circumferential direction. The annular groove 9a can be omitted if it is prevented from rotating in the circumferential direction with respect to 9.

  A movable iron core 22 is attached to the upper end in FIG. The movable iron core 22 is made of a magnetic material such as iron, nickel, cobalt, an alloy containing these, or ferrite, and has a main body portion 22a having an outer diameter larger than that of the spool valve 7, and the main body portion 22a in FIG. A connecting portion 22b that protrudes from the lower end and is screwed to the inner periphery of the upper end of the spool valve 7 in FIG. 2, a groove portion 22c provided in the main body portion 22a along the axial direction, and a connecting portion of the main body portion 22a from the upper end in FIG. A through hole 22d leading to the lower end in FIG. 2 of 22b is provided. It should be noted that when the movable iron core 22 and the spool valve 7 are integrated, means other than screwing the connecting portion 22b to the spool valve 7 may be adopted.

  The solenoid 8 includes a cylindrical stator S, the movable iron core 22 that is slidably inserted into the stator S, and a biasing spring 35 that biases the movable iron core 22. In this example, the stator S is composed of a case 30 formed of a magnetic body including an inner cylinder 30a, an outer cylinder 30b, an inner cylinder 30a, and an annular bottom portion 30c connecting the lower ends of the outer cylinder 30b in FIG. A cylindrical mold coil 31 formed by molding the coil 31a with a mold resin 31b and accommodated between the outer cylinder 30b and the inner cylinder 30a, and a cylindrical shape inserted into the inner periphery of the mold coil 31. Thus, the base 33, which is a magnetic body, is fitted to the outer periphery of the base 33 and the outer periphery of the inner cylinder 30a of the case 30 to integrate them, and an annular gap (between the base 33 and the inner cylinder 30a of the case 30) A nonmagnetic ring 32 for providing a gap) and an adjuster 34 screwed into the base 33, and a biasing spring 35 is interposed between the adjuster 34 and the movable iron core 22. There. The solenoid 8 can drive the spool valve 7 by attracting the movable iron core 22 integrated with the spool valve 7 by energizing the coil 31a. In addition, although the structure of the stator S is demonstrated in detail below, the structure of the following stator S is an example, Comprising: It is not limited to this.

  The inner cylinder 30a of the case 30 has an inner diameter set to a diameter that allows the movable iron core 22 to be slidably movable. The outer periphery of the intermediate part is connected to the annular bottom part 30c. Is bound to.

  The case 30 is accommodated in a solenoid mounting portion 6e provided at the upper end in FIG. 2 of the housing body 6 and the case 30 and the housing body 6 are connected by a seal ring 27 provided between the case 30 and the housing body 6. Sealed between. In this case, the case 30 and the housing body 6 are integrated with the case 30 and the housing body 6 as separate parts. However, the case 30 and the housing body 6 may be formed as a single part.

  Further, the inner diameter of the inner cylinder 30a of the case 30 is set to a diameter at which the outer periphery of the movable iron core 22 can be slidably contacted, while the inner diameter of the valve sleeve 9 is a diameter at which the outer periphery of the spool valve 7 can be slidably contacted. Therefore, the inner diameter of the inner cylinder 30a is larger than the inner diameter of the valve sleeve 9. Therefore, when the spool valve 7 is slidably contacted with the inner peripheral surface of the valve sleeve 9 while the movable iron core 22 is slidably contacted with the inner peripheral surface of the inner cylinder 30 a of the case 30, the movable iron core 22 is within the inner cylinder 30 a. A spool side chamber A and an anti-spool side chamber B are partitioned at both axial ends of the movable iron core 22.

The spool side chamber A is an annular chamber partitioned by the movable iron core 22, the inner cylinder 30 a, the valve sleeve 9 and the spool valve 7, and the anti-spool side chamber B is the through hole 22 d of the movable iron core 22 and the spool valve 7. It is connected to the upstream passage P through the inside. Further, the spool side chamber A and the anti-spool side chamber B are communicated with each other by a groove portion 22c formed on the outer periphery of the movable iron core 22 along the axial direction so that the spool side chamber A is not sealed. In the spool side chamber A, the elastic ring 25 exhibits a sealing function to seal between the housing body 6 and the valve sleeve 9, and the above-described seal ring 27 seals between the case 30 and the housing body 6. Other than being communicated to the non-spool side chamber B, the fluid is not communicated with any other, and the liquid does not leak into the reservoir R through the spool side chamber A. Thus, the spool side chamber A communicates with the anti-spool side chamber B without being sealed, and the spool side chamber A and the anti-spool side chamber B communicate with the upstream passage P, and the spool valve 7 and the movable iron core 22 The pressure guided from the upstream passage P acts on both ends of the movable part in the constructed solenoid valve 1. That is, the pressure receiving area that receives the pressure in the upward direction in FIG. 2 in the movable part and the pressure receiving area in the movable part that receives the pressure in the downward direction in FIG. 2 and the force in the direction of pushing down the movable part downward in FIG. 2 by the pressure from the upstream passage P as well as the force in the upward push-up direction in FIG. The pressure is not moved in the axial direction which is the vertical direction in FIG. When the spool side chamber A and the anti-spool side chamber B communicate with each other, the spool side chamber A is connected to the spool valve 7 or the movable iron core 22 instead of providing the groove 22c on the outer periphery of the movable iron core 22. Alternatively, a through hole penetrating the movable iron core 22 in the axial direction may be provided so that the spool side chamber A communicates with the anti-spool side chamber B.

Returning, an end cap 38 is fitted to the upper end of the outer cylinder 30b of the case 30 in FIG. 2, and the end cap 38 is attached by an end ring 37 screwed to the inner periphery of the opening end of the solenoid mounting portion 6c. The case 30 can be fixed in the solenoid mounting portion 6e of the housing body 6 by pressing. A seal cap 40 as a seal member is attached to the inner periphery of the end ring 37 to prevent water and dust from entering the inside.

  Although not shown, the molded coil 31 is provided with a connector, and the coil 31a can be energized from the outside via this connector. The base 33 has a cylindrical shape and is attached to the inner periphery of the molded coil 31, and includes an annular protrusion 33 a that protrudes toward the spool valve side on the outer periphery of the spool valve side end that is the lower end in FIG. 2. The outer periphery of the portion 33a is chamfered in a tapered shape. A nonmagnetic ring 32 formed of a material such as nonmagnetic stainless steel such as aluminum, copper, zinc, SUS305, high manganese steel, or the like is fitted to the outer periphery of the annular protrusion 33a and the outer periphery of the inner cylinder 30a of the case 30. The case 30 and the base 33 are integrated by the nonmagnetic ring 32. The non-magnetic ring 32 forms a gap between the base 33 and the case 30 so that the movable core 22 can be attracted by the base 33 that is magnetized when the coil 31a is energized, and the case 30 and the base 33 are integrated. Also, it plays a role of sealing between the case 30 and the base 33.

  In order to provide a gap between the base 33 and the inner cylinder 30 a of the case 30, a non-magnetic ring 32 is used, and an annular non-ring is provided between the inner cylinder 30 a of the case 30 and the annular protrusion 33 a of the base 33. The case 30 and the base 33 may be integrated by interposing a magnetic ring and brazing.

  The adjuster 34 has a shaft shape and is provided with a screw portion on the outer periphery of the base end which is the upper end in FIG. 2 and is screwed to the inner periphery of the base 33, and the lower end in FIG. A biasing spring 35 is interposed between them in a compressed state.

  Note that the lower end of the biasing spring 35 in FIG. 2 is inserted into the movable core 22 and is interposed between the movable core 22 and the adjuster 34. Then, the adjuster 34 is advanced and retracted in the vertical direction in FIG. 2, which is the axial direction with respect to the base 33 in the manner of a feed screw, and the compression length of the urging spring 35 is adjusted, whereby the urging spring 35 is applied to the spool valve 7. The initial load applied by can be adjusted.

  Further, in this embodiment, since a structure in which a part of the urging spring 35 is accommodated in the movable iron core 22 is adopted, a space for accommodating the urging spring 35 is secured, and the solenoid 8 including the adjuster 34 is secured. Can be shortened.

  When the solenoid 8 configured as described above is energized to the coil 31 a, the base 33 is magnetized and a suction force for attracting the movable iron core 22 is generated, and the spool valve 7 is resisted against the biasing force of the biasing spring 35. 2 can be driven upward.

  While the vehicle is traveling, a large acceleration in the vertical direction acts on the shock absorber D. Since this acceleration direction substantially coincides with the sliding direction of the spool valve 7, in this embodiment, the spool valve 7 In order to reduce the weight of the spool valve 7 due to the acceleration and to suppress the vibration of the spool valve 7, the overall weight of the spool valve 7 and the movable iron core 22 which are movable parts in the solenoid valve 1 is reduced. I am doing so.

  Specifically, in the solenoid valve 1, the outer diameter of the movable iron core 22 is larger than the outer diameter of the spool valve 7. More specifically, when the movable iron core 22 is attracted to the base 33 side, the movable iron core 22 also forms a magnetic path. While setting the diameter, the spool valve 7 is reduced in weight by making the outer diameter of the spool valve 7 that does not affect the magnetic path smaller than the outer diameter of the movable iron core 22, and in this way, While reducing the overall weight of the movable part of the solenoid valve 1 constituted by the movable iron core 22 and the spool valve 7, the suction force of the solenoid 8 is not reduced.

  Returning to the above, when the spool valve 7 is urged by the urging spring 35 as described above, the spool valve 7 is positioned at the lowest position in the valve sleeve 9. Specifically, when the lower end of the movable iron core 22 comes into contact with the upper end of the valve sleeve 9 in FIG. 2, the further movement of the spool valve 7 toward the piston rod 4 is restricted, and the spool valve 7 is moved to the lowermost position. Positioned.

  In this lowest position, the spool port 7a of the spool valve 7 faces the annular groove 9a of the valve sleeve 9, the spool port 7a and the downstream port 9b are in communication with each other, and the spool valve 7 is opened. Become.

  In this embodiment, by energizing the coil 31a and sucking the movable iron core 22 toward the base 33, the spool valve 7 can be retreated in the valve sleeve 9 upward in FIG. By doing so, the valve opening degree of the spool valve 7 can be adjusted by changing the lap area of the annular groove 9a and the spool port 7a (the facing area between the annular groove 9a and the spool port 7a). The flow path area in 7 can be adjusted. The spool valve 7 can be driven upward in FIG. 2 by energizing the coil 31a. If the energization to the coil 31a is stopped, the spool valve 7 can be driven downward in FIG. You can adjust the position. In short, by controlling the movement amount of the spool valve 7 by the energization amount of the coil 31a, the lap area between the annular groove 9a and the spool port 7a can be adjusted, and thereby the valve opening degree of the spool valve 7 can be adjusted. In this way, the solenoid valve 8 can drive the spool valve 7 in the vertical direction in FIG.

  Then, by restricting the flow path to the upstream passage P and the downstream port 9b formed by the annular groove 9a and the spool port 7a with the spool valve 7, the resistance given to the flow of the liquid that is going to pass through the flow path is reduced. The spool valve 7 can be increased as compared with the case where the spool valve 7 is in the lowest position. In this case, the larger the retraction amount of the spool valve 7, the smaller the lap area between the annular groove 9a and the spool port 7a, the smaller the valve opening of the spool valve 7, and the greater the degree of restriction of the flow path. As the amount of retraction of the spool valve 7 increases, the resistance given to the flow of liquid passing through the flow path increases.

  Next, the operation of the shock absorber D configured as described above will be described. When the shock absorber D in which the piston 3 moves upward in FIG. 1 with respect to the cylinder 2, the liquid in the expansion side chamber R 1 compressed by the piston 3 moves to the compression side chamber R 2 via the attenuation passage 13. In addition, when the spool valve 7 is in the open state, the liquid in the extension side chamber R1 pushes open the check valve 4e that allows only the liquid to pass from the extension side chamber R1 to the reservoir R, thereby reducing the damping force. An attempt is made to move to the reservoir R through the adjustment passage 5, the upstream passage P, the throttle valve O, the spool port 7a, the annular groove 9a, the downstream port 9b, the annular groove 6c, and the discharge passage 6d. The buffer D provides resistance to the liquid flow in the damping passage 13 and also restricts the throttle valve O and the spool valve 7 in the solenoid valve 1 against the liquid flow from the extension side chamber R1 to the reservoir R. Give resistance by. That is, in this embodiment, the shock absorber D exerts an extension side damping force by the damping passage 13 and the solenoid valve 1 at the time of extension. Therefore, if the valve opening degree of the spool valve 7 is adjusted by the solenoid valve 1, the damping force generated when the shock absorber D is extended can be adjusted. The smaller the valve opening degree of the spool valve 7, the shock absorber. D exhibits a large damping force. Note that liquid is supplied from the reservoir R through the suction passage 16 provided in the bottom member 14 to the pressure side chamber R2 that expands when extended, and the piston rod 4 retreats from the cylinder 2 when the shock absorber D extends. The change in the volume in the cylinder 2 occurring at is compensated.

  On the contrary, when the shock absorber D in which the piston 3 moves downward in FIG. 1 with respect to the cylinder 2 contracts, the damping passage 13 resists the flow of the liquid moving from the compression side chamber R2 to the expansion side chamber R1. In addition, the volume-reduced liquid in the cylinder 2 generated by the piston rod 4 entering the cylinder 2 is discharged to the reservoir R through the compression-side damping passage 15 of the bottom member 14 to change the volume in the cylinder 2. Therefore, the pressure side damping passage 15 also provides resistance to the liquid flow. Therefore, when the shock absorber D is contracted, the damping side passage 13 and the pressure side damping passage 15 exhibit a compression side damping force. In this case, no liquid flows through the damping force adjusting passage 5. Does not participate in the generation of the compression damping force.

  That is, in this embodiment, in the solenoid valve 1, by driving the spool valve 7, the flow passage area of the flow passage leading to the upstream passage P and the downstream port 9b can be made variable. Then, the extension side damping force at the time of expansion | extension can be adjusted now.

  In this solenoid valve 1, a throttle valve O is provided upstream of the spool valve 7, and the liquid that passes through the solenoid valve 1 passes through the spool valve 7 and then passes through the spool valve 7 to the outside. Is discharged into the reservoir R.

  Here, when the throttle valve O is not installed and there is almost no pressure loss even if the liquid passes through the upstream passage P, the flow of the liquid is restricted only by the spool port 7a and the annular groove 9a. Pressure loss will occur. In this case, the pressure distribution in the spool port 7a at the time when the liquid flow rate is increased and the pressure is reduced, as shown in FIG. 3, the right end side of the spool port 7a in FIG. The left end is at high pressure. Therefore, among the inner walls of the spool port 7a, a low pressure acts on the inner wall on the tip side of the spool valve 7 which is the lower end in FIG. 2, and a high pressure acts on the inner wall on the solenoid side which is the upper end in FIG. The pressure balance acting on the inner wall of the port 7a is biased, and a force to push the spool valve 7 upward in FIG.

  On the other hand, in the solenoid valve 1 of the present invention, the throttle valve O is disposed upstream of the spool valve 7 and is decompressed by the throttle valve O on the upstream side of the spool valve 7. In this case, the pressure distribution in the spool port 7a at the time when the liquid flow rate is increased and the pressure is reduced is roughly the same as that shown in FIG. The right end side in FIG. 4 of the port 7a is a low pressure, and the left end side in FIG. 4 is a medium pressure. Thus, in the solenoid valve 1 of the present invention, the throttle valve O is provided because the upstream pressure is reduced by the throttle valve O even if the flow rate of the liquid is increased and the pressure is reduced in the spool port 7a. Even if the pressure balance acting on the inner wall of the spool port 7a is biased as compared with the case where there is no pressure, the pressure acting on the inner wall of the spool port 7a on the tip side which is the lower end in FIG. And the difference of the pressure which acts on the inner wall by the side of the solenoid which becomes the upper end in FIG. 2 of the spool valve 7 becomes small. Therefore, even if the pressure balance acting on the inner wall of the spool port 7a is biased, the force that pushes the spool valve 7 upward in FIG. 2 in the valve closing direction can be reduced by providing the throttle valve O. In order to facilitate understanding of the pressure distribution, the pressure distribution is roughly described as low pressure, high pressure, and medium pressure (intermediate pressure between low pressure and high pressure), and the boundaries of each pressure are shown. In this case, the pressure gradually changes, and a low pressure may be generated in the high pressure range by the flow of the liquid, but this does not affect the effect of the present invention.

  Thus, since the force that pushes up the spool valve 7 in the valve closing direction by passing through the spool valve 7 can be reduced, the set load applied in advance to the biasing spring 35 is increased with respect to the force. There is no need to compete.

  Therefore, in the solenoid valve 1 of the present invention, the dead zone in which the spool valve 7 does not move even when current is supplied to the solenoid 8 can be reduced, and the flow rate controllability is impaired particularly in a low pressure region where the flow rate is small. There is no.

  Further, in the solenoid valve 1 of the present invention, since the force for moving the spool valve 7 in the valve closing direction which is the upper side in FIG. 2 with respect to the housing E is reduced, the solenoid 8 drives the spool valve 7. Therefore, the thrust required for this is small, and the positioning accuracy of the spool valve 7 by the solenoid 8 is improved, so that the solenoid valve 1 of the present invention can exhibit a stable damping force.

  In this solenoid valve 1, the housing E is provided with a housing main body 6 and a valve sleeve 9 that is accommodated in the housing main body 6 and has an annular groove 9 a and a downstream port 9 b. Is supported by the housing body 6 so as to be allowed to move in the radial direction, and a moment from the vehicle body side tube 10 acts on the housing body 6 to cause the housing body 6 to be elastically deformed or repeated over a long period of time. Even if the housing main body 6 is plastically deformed by the action of the stress, the positional relationship in the radial direction between the valve sleeve 9 and the spool valve 7 hardly changes, and the smooth drive of the spool valve 7 is guaranteed. Therefore, in the solenoid valve 1 of the present embodiment, even when applied to the shock absorber D in which a moment acts on the housing body 6, it is possible to prevent the damping force generation response of the shock absorber D from deteriorating. Therefore, a stable damping force can be exhibited.

The valve sleeve 9 is floatingly supported on the housing body 6 via annular elastic rings 25 and 26 disposed on both sides of the discharge passage 6d and the downstream port 9b in the axial direction. Since a sealing function for sealing between the housing main body 6 is provided, a sealing member for separately sealing between the valve sleeve 9 and the housing main body 6 becomes unnecessary, and the number of parts and cost can be reduced.

  In the solenoid valve 1 of this embodiment, the outer diameter of the movable iron core 22 is made larger than the outer diameter of the spool valve 7, and the movable iron core 22 is partitioned in the stator S by the movable iron core 22 on both sides in the axial direction. The spool side chamber A and the anti-spool side chamber B communicate with each other. Thus, by setting the outer diameter of the movable iron core 22 to be larger than the outer diameter of the spool valve 7, when adjusting the damping force, the spool valve 7 is driven by the solenoid 8 as necessary to reduce the flow path area. When changing, the entire weight of the movable part of the solenoid valve 1 composed of the movable iron core 22 and the spool valve 7 can be reduced without causing a decrease in the suction force of the solenoid 8. The vibration of the spool valve 7 can be suppressed by making the inertial force acting on the movable part by a large acceleration in the expansion / contraction direction, which is input in the shock absorber D, small.

  Further, the spool valve 7 and the movable iron core 22 are formed in a cylindrical shape, and the spool side chamber A and the anti-spool side chamber B, which are partitioned in the stator S by the movable iron core 22 on both sides in the axial direction of the movable iron core 22, communicate with each other. Therefore, even if a high pressure acts on the movable part of the solenoid valve 1, the force that pushes the movable part downward in FIG. 2 and the force that pushes the movable part upward in FIG. Does not move in any axial direction. Therefore, in this solenoid valve 1, even if a high pressure acts on the movable part, adjustment of the flow path area by the solenoid 8 is not affected. As a result, the problem that the thrust of the solenoid 8 must be increased so as to overcome the pressure from the upstream passage P side can be solved, and the damping force can be adjusted by driving the spool valve 7 with the small solenoid 8. it can. From the above, it is possible to adjust the flow path area even if the force for attracting the movable iron core 22 of the solenoid 8 is small, and the magnetic path cross-sectional area in the movable iron core 22 can be further reduced and the magnetic path is affected. Since the spool valve 7 that does not give a smaller diameter than the movable iron core 22 can be reduced in weight and vibration of the spool valve 7 can be suppressed, according to the solenoid valve 1 of the present embodiment, the input vibration Therefore, it is possible to prevent the damping force generated by the shock absorber D from changing vibrationally without becoming the aimed damping force. As described above, a stable damping force can be exhibited against vibration input while using the solenoid 8, so that the solenoid valve 1 can be used for the shock absorber D. Therefore, the solenoid valve 1 can dramatically improve the damping force adjustment response of the shock absorber D, and can perform damping force adjustment by active control such as skyhook control while exhibiting stable damping force. In particular, it is most suitable for a shock absorber used in a saddle-riding vehicle that is suitable for running on rough roads where a large vertical acceleration acts.

  Further, since the spool valve 7 can be driven without increasing the size of the solenoid 8, the shock absorber D can be mounted on a small vehicle such as a saddle vehicle without impairing the mountability. There is no problem of high economic efficiency.

  In the present embodiment, since the spool valve 7 is made of a material having a specific gravity smaller than that of the movable iron core 22, the solenoid valve is compared with the case where the spool valve 7 is made of the same material as the movable iron core 22. 1 is designed to reduce the overall weight of the spool valve 7 and the movable iron core 22, which are movable parts, and the spool valve 7 is subjected to a large acceleration in the expansion / contraction direction that is input to the shock absorber D during vehicle travel. Since the inertial force acting can be made even lighter and the vibration of the spool valve 7 can be made lighter, the damping force generated by the solenoid valve 1 can be vibrated without changing to the aimed damping force. Can be prevented, and more stable damping force can be exhibited.

  Further, in the solenoid valve 1 of the present embodiment, a groove 22c is provided along the axial direction on the outer periphery of the movable iron core 22 so that the spool side chamber A and the anti-spool side chamber B communicate with each other. Even when the hole of the core 22 is provided along the axial direction and the spool side chamber A and the anti-spool side chamber B are communicated with each other, the forming process of the groove 22c on the outer periphery of the movable core 22 is easy to process. Excellent and easy to process.

  In the above description, the throttle valve O is provided in the plug 20 and the plug 20 is detachably screwed into the passage portion 6b of the housing main body 6. Therefore, according to the damping characteristic realized by the solenoid valve 1. By replacing the plug 20 with a different orifice diameter, the characteristics of the solenoid valve 1 can be easily changed and tuned. Further, as shown in FIG. 5, a throttle valve O formed of an orifice hole in the shape of a disk and penetrating in the axial direction between the end surface 6i of the accommodating portion 6a of the housing body 6 and the lower end of the valve sleeve 9 in FIG. Orifice plate 41 may be interposed. The orifice plate 41 is thus sandwiched between the housing body 6 and the valve sleeve 9 and fixed to the housing E. However, if the valve sleeve 9 is removed from the housing body 6, the orifice plate 41 can be easily replaced. Even when the plate 41 is used, the characteristics of the solenoid valve 1 can be easily changed and tuned. As described above, it is possible to easily change the characteristics of the solenoid valve 1 by using the plug 20 and the orifice plate 41. However, the inner diameter in the middle of the passage portion 6b of the housing main body 6 is reduced to a small diameter. It is also possible to provide O directly on the housing body 6. When the plug 20 is attached to the housing body 6 or the throttle valve O is provided directly on the housing body 6, there is no need to sandwich the orifice plate 41 between the valve sleeve 9 and the housing body 6. Then, a structure in which the spool valve 7 is slidably accommodated in the housing body 6 may be employed. In addition, the throttle valve O only needs to be disposed upstream of the spool valve 7, and is not provided in the upstream passage P. In this embodiment, the solenoid valve 1 is connected to the damping force adjusting passage 5 in the shock absorber D. It may be provided in the damping force adjusting passage 5.

  The shock absorber D in the present embodiment includes a vehicle body side tube 10 connected to the body of the saddle vehicle and an axle side tube 11 connected to the axle of the saddle vehicle. The piston rod 4 is connected to the vehicle body side tube 10 via the connected housing body 6 and the cylinder 2 is connected to the axle side tube 11 so that the shock absorber D is formed by the vehicle body side tube 10 and the axle side tube 11. L is accommodated in L, a reservoir R is formed in the space L and outside the shock absorber D, and the upstream passage P is communicated with the pressure side chamber R2 or the extension side chamber R1 in the cylinder 2 through the piston rod 4, and the downstream port 9b communicates with the reservoir R. As a result, the solenoid valve 1 can be concentrated above the vehicle body side tube 10 and the solenoid 8 can be easily energized, and the solenoid valve 1 is damped by the shock absorber D on the vehicle body side. Therefore, the vibration of the spool valve 7 during traveling of the vehicle can be suppressed, and the fluctuation of the damping force due to the vibration can be suppressed.

  Further, the shock absorber D includes a hole 4b in which the piston rod 4 extends in the axial direction, and the piston rod 4 and the housing E connected to the tip of the piston rod 4 coaxially connect the hollow portion C and the hole 4b. They are connected in series. As a result, the driving direction of the spool valve 7 coincides with the axial direction of the piston rod 4, so that the solenoid 8 that drives the spool valve 7 does not protrude sideways, and the driving direction of the spool valve 7 is changed to the axis of the piston rod 4. The shock absorber D can be made slim compared with the case where the crossing direction is set to the direction crossing with respect to. Of course, in exchange for the effect, the driving direction of the spool valve 7 may be different from the expansion / contraction direction of the shock absorber D, that is, it may not coincide with the axis of the piston rod 4. Therefore, the vibration in the drive direction of the spool valve 7 can be suppressed by the vibration.

  Furthermore, the shock absorber D in the present embodiment is provided with an adjuster 34 that adjusts the initial load of the biasing spring 35 of the solenoid 8 facing the outside of the shock absorber D from the opening end of the vehicle body side tube 10. Thereby, since the adjuster 34 can be externally operated, the initial load can be easily adjusted. In addition, when the spring constant of the urging spring 35 varies, by performing this initial load adjustment, it is possible to perform a uniform damping force adjustment without variation among products. The damping force adjustment of the shock absorber D may be made uniform by correcting the amount of current applied to the solenoid 8.

As described above, the solenoid valve 1 allows the liquid to pass only when the shock absorber D is extended, and functions as a damping force generating element that generates the extension side damping force of the shock absorber D. Therefore, the expansion side damping force of the shock absorber D can be adjusted, but the pressure side damping force of the shock absorber D is set by allowing the liquid to pass only when the shock absorber D contracts. The compression side damping force may be adjusted by functioning as a damping force generating element to be generated. That is, if the pressure side chamber R2 is communicated to the air hole 4b instead of the expansion side chamber R1 through the communication passage 4d provided in the piston connecting portion 4c, the solenoid valve 1 can adjust the pressure side damping force. If it does in this way, it can set so that a liquid may pass only at the time of contraction operation of shock absorber D.

  In addition, when a damping passage that communicates the extension side chamber R1 and the pressure side chamber R2 is provided and the solenoid valve 1 is provided in the middle of the damping passage, the solenoid valve 1 is used both when the shock absorber D is extended and contracted. The damping force can be adjusted. In this case, for example, the housing is used as a piston rod or piston coupling part to accommodate the spool valve, and the piston rod or piston coupling part is provided with a flow path that connects the expansion side chamber R1 and the pressure side chamber R2, and the spool valve is driven by a solenoid. May be.

  Furthermore, as described above, the flow path area is set to decrease when the spool valve 7 is retracted, but the spool valve 7 is set to minimize the flow path area at the lowest position, The flow path area may be increased by the retraction of the spool valve 7, or the flow path may be completely blocked by the spool valve 7.

  Further, the housing body 6 may be integrated with the piston rod 4 to be a single part, or the housing body 6 may be constituted by a plurality of parts. Further, in the above embodiment, the connector 31d for energizing the coil 31a is integrated with the molded coil 31, but the connector 31d is separated from the molded coil 31, and the coil 31a and the power supply terminal 31c are connected by a cord. Alternatively, the connector and the power terminal may be eliminated, and the coil 31a may be connected to an external power source only through a cord.

  Further, when the solenoid valve 1 exhibits a damping force when the shock absorber D extends, the shock absorber D may be configured to exhibit a damping force only when the shock absorber D extends. When the damping force is exerted when the vehicle is contracted, a configuration in which the damping force is exhibited only when the vehicle is contracted may be adopted. When the shock absorber D is applied to the vehicle in a pair of left and right to support the wheels, One of the shock absorbers D may be set to exhibit a damping force when extended, and the other may exhibit a damping force when contracted.

  This is the end of the description of the embodiment of the present invention, but the scope of the present invention is of course not limited to the details shown or described.

DESCRIPTION OF SYMBOLS 1 Solenoid valve 2 Cylinder 4 Piston rod 5 Damping force adjustment path 6 Housing main body 6a Accommodating part 6b Passage part 6i End surface 7 Spool valve 7a Spool port 8 Solenoid 9 Valve sleeve 9a Recessed part 9b Downstream port 20 Plug 41 Orifice plate C Hollow part D Buffer E E Housing O Throttle valve P Upstream passage R1 Extension side chamber R2 Pressure side chamber

Claims (4)

A housing having a downstream port leading to the upstream passage and the hollow portion communicates with the hollow portion and the hollow portion,
A spool valve that has a spool port that communicates inside and outside with a cylindrical shape, and is slidably inserted into the hollow portion in the axial direction;
A solenoid that drives the spool valve in the axial direction;
A solenoid valve capable of communicating the upstream passage to the downstream port via the spool port and the spool valve and capable of adjusting the degree of communication between the spool port and the downstream port by driving the spool valve; There,
A solenoid valve characterized in that a throttle valve is provided upstream of the spool valve to reduce the pressure upstream of the spool valve and reduce the force pushing the spool valve in the valve closing direction . The solenoid valve according to claim 1, wherein the throttle valve is installed by screwing a plug having an orifice into the upstream passage provided in the housing. The housing includes a cylindrical valve sleeve having a said hollow portion and said downstream port, continuous with housing part and the housing part accommodating the valve sleeve to the inner circumference a cylindrical smaller diameter than the housing part A housing body having a passage portion forming the upstream passage,
The throttle valve, a solenoid valve according to orifice plate with an orifice to claim 1, characterized in that it is installed by sandwiched between the end surface of the housing portion of the valve sleeves and the housing body. Cylinder and a piston which is slidably inserted into said cylinder within said cylinder liquid is divided into a pressure side chamber and expansion side chamber to be filled, a piston rod connected to the piston is inserted into the cylinder When the damping force control passage to permit passage of liquid in one or both during contraction and elongation at, and a solenoid valve according to one of any claims 1-3 provided in the damping force control passage Provided shock absorber.

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