JP6006494B2 - 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 adjusting valve that can adjust the damping force of the shock absorber during travel, a cylindrical valve body is inserted into the inner periphery of a cylindrical piston rod, and this cylindrical valve body is driven by a stepping motor. 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 valve body having an orifice hole that can face the port is inserted into the piston rod. The damping force adjusting valve adjusts the damping force generated by the shock absorber by changing the lap area of the port and the orifice hole by rotating the cylindrical valve body within the piston rod with a stepping motor. (For example, refer to Patent Document 1).

  In the damping force adjusting valve described above, the wrap area between the port and the orifice hole is made variable by rotating the cylindrical valve body within the piston rod using a stepping motor. By driving in the axial direction of the piston rod, the lap area between the port and the orifice hole can be made variable. Here, in order to drive the cylindrical valve body in the axial direction, for example, a solenoid can be used.

JP 2008-39065 A

  By the way, since the cylindrical valve body has a flow path inside, it is necessary to provide an orifice hole that opens from the side and communicates with the inside, but when laser processing is used when providing this orifice hole, Since the valve body is thick, the above processing could not be performed unless the laser output was increased.

  For this reason, there is a problem that the dimensional accuracy is deteriorated and a large amount of burrs are generated around the orifice hole after laser processing, and the difficulty of finishing processing for deburring increases.

  Further, when the hydraulic oil passes through the orifice hole, the faster the hydraulic oil flows, the lower the pressure. Here, when reducing the lap area of the port and the orifice hole with the cylindrical valve body, the cylindrical valve body is moved and driven so that the side surface of the cylindrical valve body faces the port. If the flow rate does not change, the flow of hydraulic oil passing through the orifice hole becomes faster. If the wrapping area of the orifice hole and the port end are made small enough to wrap the orifice hole, the flow of hydraulic fluid through the orifice hole becomes faster at the end of the orifice hole. The pressure acting on the cylinder is not uniform, and a force in the direction of reducing the lap area acts on the cylindrical valve body.

  The larger the cylindrical valve body is, and the faster the hydraulic oil flows through the orifice hole, the lower the pressure of the hydraulic oil flowing through the orifice hole and the port. Then, the force to reduce this lap area increases. On the other hand, the solenoid is provided with a spring that urges the cylindrical valve body, and drives the cylindrical valve body to a position where the suction force generated during energization and the urging force of the spring are balanced. For this reason, when considering driving the cylindrical valve element 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 flow of the liquid causes the cylindrical valve Since the force in the direction of closing the port is increased in the body, there is a problem that the position of the cylindrical valve body is shifted from the target position and the damping force as intended cannot be exhibited.

  Therefore, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a solenoid valve and a shock absorber that are excellent in workability and can exhibit a stable damping force. It is.

To achieve the above object, problem-solving means of the present invention, the spool port communicating with the housing, the inner and outer a cylindrical shape having a port which opens from the hollow portion and the outer communicated to the hollow portion A spool valve that is slidably inserted into the hollow portion in the axial direction, and a solenoid that drives the spool valve in the axial direction. The spool valve is driven to drive the port and the spool port. The solenoid valve capable of adjusting the degree of communication is characterized in that a thin portion having a thickness thinner than outside the above range is provided in a range where at least the spool port is provided from one end of the spool valve.

  In this solenoid valve, since the spool port is provided in the thin wall portion, when the spool port is drilled in the spool valve by laser processing, the laser output may be small, and the amount of burrs generated is also reduced. Finishing is also easy. Furthermore, since the area of the wall surface of the hole forming the spool port is reduced by providing the spool port in the thin wall portion, the spool valve is moved even if the flow of liquid passing through the spool port becomes faster and the pressure decreases. The force is small, the thrust required for the solenoid to drive the spool valve is small, and the positioning accuracy of the spool valve by the solenoid is improved.

  Therefore, according to the solenoid valve and the shock absorber of the present invention, it is excellent in workability and can exhibit a stable damping force.

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 sectional drawing of the movable iron core and spool valve in the solenoid valve of one modification of one Embodiment.

  The present invention will be described below based on the embodiments shown in the drawings. As shown in FIG. 1, the solenoid valve 1 in one embodiment has a hollow housing 6 having a port 6 b that opens from the outside and communicates with the hollow portion 6 a, and a cylindrical shape that communicates between the inside and the outside. The spool valve 7 has a spool port 7a that is inserted into the hollow portion 6a so as to be movable in the axial direction, and a solenoid 8 that drives the spool valve 7 in the axial direction.

  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 coupled to the piston 3, and a damping force adjusting flow path 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 middle of the flow path 5 to adjust the damping force generated by the shock absorber D.

  In this example, the shock absorber D further includes a vehicle body side tube 10 in which the piston rod 4 is coupled to a vehicle body (not shown) of a saddle vehicle such as a two-wheeled vehicle, and a saddle vehicle. It is accommodated in a front fork F that is composed of an axle side tube 11 that is connected to an axle (not shown) 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 6, and the cylinder 2 is connected to the axle side tube 11, so that the shock absorber D is located between the vehicle body side tube 10 and the axle side tube 11. Is housed in the space L which is inside the front fork F closed by the vehicle body side tube 10 and the axle side tube 11. 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 which is the upper end in FIG. 1 is fixed to the upper end of the vehicle body side tube 10 via the housing 6 housing the spool valve 7 in the solenoid valve 1 and the case 30 of the solenoid 8. Yes. 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.

  And the suspension spring 12 is interposed between the rod guide 17 and the cylindrical spring receiver 18 provided on the outer periphery of the housing 6, and the shock absorber body D is urged in the extension direction by the suspension spring 12. 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 provided in the middle of the flow path 5 described above, and includes a housing 6 having a hollow portion 6a, a spool valve 7 slidably inserted into the hollow portion 6a of the housing 6, and a spool valve. 7 includes a movable iron core and a solenoid 8 that drives the spool valve 7 within the hollow portion 6a.

  As shown in FIGS. 1 and 2, the housing 6 has a hollow portion 6a inside and is formed into a cylindrical shape. The housing 6 has an annular groove 6c provided on the inner periphery and an annular groove opened from the outer periphery. The port 6b communicates with the hollow portion 6a through 6c, and an annular socket 6d provided at the upper end in FIG. Further, a screw hole portion 6e is provided in the lower inner periphery of the hollow portion 6a of the housing 6 in FIG. 2, and a screw portion 4f is provided on the outer periphery of the upper end of the piston rod 4, so that the screw hole portion 6e has an inner portion. A screw can be fastened while inserting the upper end of the piston rod 4. 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 6 in FIG. Thus, consideration is given so that the screw hole 6e and the screw 4f are not loosened.

  When the housing 6 is coupled to the piston rod 4 in this way, the hollow portion 6a is coaxially connected in series with the hole 4b of the piston rod 4, and the hollow portion 6a is connected via the hole 4b and the communication path 4d. And communicated with the extension side chamber R1 in the shock absorber D. The hollow portion 6a communicates with a reservoir R formed outside the shock absorber D through a port 6b. Therefore, in the case of this embodiment, the flow path 5 is constituted by the communication path 4d, the hole 4b, the hollow portion 6a, the annular groove 6c, and the port 6b described above, and the extension side chamber R1 and the reservoir R communicate with each other. doing. Further, in this case, the flow path 5 allows only the passage of liquid from the extension side chamber R1 to the reservoir R by the check valve 4e. The check valve for setting the flow path 5 to be one-way is not provided in the piston connecting portion 4c but may be provided in another location. Specifically, for example, the check valve is provided in the hole 4b of the piston rod body 4a. Alternatively, the piston rod body 4a may be provided at the open end of the hole 4b at the upper end in FIG.

  The spool valve 7 has a cylindrical shape and is slidably inserted into the hollow portion 6a. The spool valve 7 includes a spool port 7a that communicates with the hollow portion 6a from the side to communicate the inside and the outside of the spool valve 7. . In the case of this embodiment, the spool valve 7 is configured such that the inner diameter of the range H in which the spool port 7a is provided from the lower end which is one end of the spool valve 7 is larger than the inner diameter outside the range H. A thin portion 7b provided with a reduced thickness of H is provided. In other words, the spool port 7a is provided within a range where the thin portion 7b of the spool valve 7 is provided. The range in which at least the spool port 7a is provided from one end is the thin portion 7b. The range H in which the thin portion 7b is provided is from one end of the spool valve 7 to the edge on the other end side of the spool valve in the spool port 7a. It may be up to the upper edge in FIG. 2, or may be a range including the upper part in FIG. In order to provide the spool valve 7 with the thin wall portion 7b, it is necessary to perform processing such as cutting the inner peripheral side. Therefore, the position where the spool port 7a is provided is from one end of the spool valve 7 to the center in the axial direction. The range in which the thin portion 7b is provided can be less than half the axial length of the spool valve 7, which is economical. Therefore, in the present embodiment, the closer the position where the spool port 7a is provided to the spool valve 7 is closer to one end of the spool valve 7, the shorter the processing length for forming the thin portion 7b and the more economical. It will be. The thin portion 7b can be provided by making the outer diameter of the range H in which the thin portion 7b is provided smaller than the outer diameter outside the range H. In this case, the shape of the hollow portion 6a of the housing 6 is spooled. When it is necessary to set the shape to be in sliding contact with the outer periphery of the thin portion 7 b without obstructing the stroke of the valve 7, and when the inner periphery of the hollow portion 6 a is also in sliding contact with the outer periphery outside the range H of the spool valve 7. Is a high degree of processing accuracy due to the coaxiality at two locations between the hollow portion 6a of the housing 6 and the outer periphery of the range H of the spool valve 7 and between the hollow portion 6a and the outer periphery of the range H. However, by setting the inner diameter of the range H where the spool port 7a is provided from the lower end, which is one end of the spool valve 7, to be larger than the inner diameter outside the range H, the thickness of the range H can be reduced. When providing the thin part 7b that is thin, Entire valve 7 there is also an advantage that machining is easy to sliding contact with the hollow portion 6a of the housing 6.

  When the spool valve 7 slides in the hollow portion 6a of the housing 6 and the spool port 7a faces the annular groove 6c, the spool port 7a and the port 6b are in communication with each other and the flow path 5 is opened. When the spool port 7a is not opposed to the annular groove 6c and the side surface of the spool valve 7 closes the annular groove 6c, the communication between the spool port 7a and the port 6b is cut off and the flow path 5 is blocked. The annular groove 6c is provided to enable communication between the port 6b and the spool port 7a even when the spool valve 7 rotates in the circumferential direction. The annular groove 6 c may be omitted when the spool valve 7 is prevented from rotating in the circumferential direction with respect to the housing 6.

  An annular movable iron core 22 is attached to the upper end in FIG. The spool valve 7 is made of a nonmagnetic material having a specific gravity smaller than that of the movable iron core 22, and is made of a material such as aluminum, aluminum alloy, magnesium alloy, or synthetic resin.

  The movable iron core 22 is formed of a magnetic material such as iron, nickel, cobalt, an alloy containing these, ferrite, or the like, has an annular shape, and includes an inner peripheral flange 22a that protrudes inward on the inner periphery. The outer diameter of the movable iron core 22 is larger than the outer diameter of the spool valve 7, and the inner diameter of the movable iron core 22 is such that the upper end of the spool valve 7 can be fitted. 2, the upper end in FIG. 2 of the spool valve 7 is fitted and fixed to the inner periphery of the lower end in FIG. When the movable iron core 22 and the spool valve 7 are integrated, the upper end of the spool valve 7 may be press-fitted into the movable iron core 22 or shrink-fitted, or the two may be integrated. It is also possible to employ other fixing methods. In this case, since the movable iron core 22 includes the inner peripheral flange 22 a, the spool valve 7 is pushed against the movable iron core 22 by pushing the spool valve 7 into the movable iron core 22 until it abuts against the inner peripheral flange 22. Is positioned in the axial direction, and further intrusion of the spool valve 7 into the movable iron core 22 is prevented, but the inner peripheral flange 22a can be omitted.

  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. An annular gap is formed between the base 33 and the inner cylinder 30a of the case 30. The base 33, which is a magnetic body, is fitted to the outer circumference of the base 33 and the inner circumference of the inner cylinder 30a of the case 30 to integrate them. A nonmagnetic ring 32 for providing a (gap) and an adjuster 34 screwed into the base 33 are provided. 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 so that the movable iron core 22 can be inserted movably. The outer periphery of the intermediate part is connected to the annular bottom 30c, and the outer cylinder 30b is connected to the outer cylinder 30b via the annular bottom 30c. Are combined. Further, the lower end of the inner cylinder 30a in FIG. 2 is fitted into a socket 6d provided at the upper end of the housing 6 in FIG. 2, so that the case 30 and the housing 6 are integrated. The inner cylinder 30a and the socket 6d can be coupled by a coupling method such as welding, press fitting, or screw fastening. In this case, the case 30 and the housing 6 are separate parts, and the case 30 and the housing 6 are integrated. However, the case 30 and the housing 6 may be configured as one part.

  The inner diameter of the inner cylinder 30a of the case 30 is set to a diameter that allows the outer periphery of the movable iron core 22 to be in sliding contact, while the diameter of the hollow portion 6a that is the inner diameter of the housing 6 is in contact with the outer periphery of the spool valve 7. Therefore, the inner diameter of the inner cylinder 30 a is larger than the inner diameter of the housing 6. For this reason, when the spool valve 7 is slidably contacted with the inner peripheral surface of the hollow portion 6a of the housing 6 while the movable iron core 22 is slidably contacted with the inner peripheral surface of the inner cylinder 30a of the case 30, it is movable within the inner cylinder 30a. A spool side chamber A and an anti-spool side chamber B are partitioned by the iron core 22 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 and the spool valve 7, and the anti-spool side chamber B flows through the inner side of the movable iron core 22 and the spool valve 7. 5 is connected. Further, the spool side chamber A and the anti-spool side chamber B are communicated with each other by a groove 22b along the axial direction formed on the outer periphery of the movable iron core 22, so that the spool side chamber A is not sealed. In this way, 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 flow path 5 and are constituted by the spool valve 7 and the movable iron core 22. The pressure guided from the flow path 5 acts on both ends of the movable portion of the solenoid valve 1 thus formed. That is, the pressure receiving area that receives pressure in the direction in which the movable part is pushed upward in FIG. 2 and the pressure receiving area that receives pressure in the direction in which the movable part is pushed down in FIG. 2 are equal. 2, the force in the direction of pushing up the movable part is equal to the force in the direction of pushing down the movable part in FIG. 2 by the pressure from the flow path 5, and the movable part is illustrated by the pressure from the flow path 5. 2 is not moved in the axial direction, which is the vertical direction. When the spool side chamber A and the anti-sproll side chamber B communicate with each other, instead of providing the groove 22b on the outer periphery of the movable core 22, the spool side chamber A is connected to the spool valve 7 or the movable core 22 with the inner periphery of the spool valve 7 or the movable 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.

  In this example, a flange 30d is provided on the outer periphery of the outer cylinder 30b of the case 30 in FIG. 2, and a screw portion 30e is provided on the outer periphery of the flange 30d. The case 30 can be screwed to the vehicle body side tube 10 by screwing the flange 30d of the case 30 to the opening end of the vehicle body side tube 10, and the piston can be connected via the case 30 and the housing 6 coupled thereto. The rod 4 can be connected to the vehicle body side tube 10.

  The molded coil 31 includes a cylindrical connector 31d that houses a power supply terminal 31c for energizing the coil 31a. The connector 31d is integrated with the coil 31a by a molded resin 31b. By connecting the power supply terminal 31c in the connector 31d to an external power supply (not shown), the coil 31a can be energized from the outside.

  The base 33 has a cylindrical shape and is inserted into the inner periphery of the molded coil 31, and includes an annular convex portion 33a that protrudes toward the spool valve side on the outer periphery of the spool valve side end, which is the lower end in FIG. The outer periphery of the annular convex 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.

  Further, an annular end ring 37 having a split 37a that allows the connector 31d to pass therethrough is laminated on the outer periphery of the base 33 and on the upper end of the molded coil 31 in FIG. The end ring 37 is screwed to the inner periphery of the upper end in FIG. 2 of the outer cylinder 30b of the case 30 and cooperates with the case 30 to form a molded coil 31, a non-magnetic ring 32 integrated with the mold coil 31, and a base. 33, and these members are fixed to the case 30.

  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.

  The biasing spring 35 is inserted between the inner peripheral flange 22a of the movable iron core 22 and the adjuster 34 with the lower end in FIG. 2 inserted into the movable iron core 22, but as described above, If the circumferential flange 22a is omitted, the lower end of the biasing spring 35 may be received by the upper end of the spool valve 7 in FIG. 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, to adjust the compression length of the biasing spring 35, thereby 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. 2 is thicker than the inner peripheral flange 22a of the movable iron core 22 on the spool valve side, which is lower in FIG. 2, so that the magnetic path is cut off. It is easy to ensure the area, and care is taken so that the magnetic flux density is not saturated and the attractive force 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 hollow portion 6a. Specifically, when the lower end of the spool valve 7 comes into contact with the upper end of the piston rod 4, further movement of the spool valve 7 toward the piston rod 4 is restricted, and the spool valve 7 is positioned at the lowest position. . The spool valve 7 may be positioned at the lowest position by bringing the lower end of the movable iron core 22 into contact with a step portion 6 f formed on the inner periphery of the housing 6.

  In this lowest position, the spool port 7a of the spool valve 7 faces the annular groove 6c of the housing 6, the spool port 7a and the port 6b are in communication with each other, and the flow path 5 is opened.

  In this embodiment, the spool valve 7 is retracted upward in FIG. 2 in the hollow portion 6a of the housing 6 by energizing the coil 31a and sucking the movable iron core 22 toward the base 33. In this way, the degree of communication between the port 6b and the spool port 7a can be adjusted by changing the lap area between the annular groove 6c and the spool port 7a (the area where the annular groove 6c and the spool port 7a face each other). The flow passage area in the solenoid valve 1 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 amount of movement of the spool valve 7 according to the amount of current supplied to the coil 31a, the lap area between the annular groove 6c and the spool port 7a can be adjusted, thereby adjusting the degree of communication between the port 6b and the spool port 7a. 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 5 by the annular groove 6c and the spool port 7a, the resistance given to the flow of the liquid that is going to pass through the flow path 5 is larger than when the spool valve 7 is in the lowest position. can do. In this case, the larger the retraction amount of the spool valve 7, the smaller the lap area between the annular groove 6c and the spool port 7a and the greater the degree of throttling of the flow path 5, so that the retraction amount of the spool valve 7 increases. Accordingly, the resistance given to the flow of the liquid passing through the flow path 5 is increased.

  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 is extended, a resistance is given to the flow of the liquid moving from the expansion side chamber R1 to the compression side chamber R2 compressed by the piston 3 by the damping passage 13. The solenoid valve 1 provides resistance to the flow of liquid from the extension side chamber R1 to the reservoir R. 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. 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 contracts, the damping passage 13 and the pressure-side damping passage 15 exert a compression-side damping force. In this case, since the liquid does not flow through the flow path 5, the solenoid valve 1 It is not involved in the generation of damping force.

  That is, in this embodiment, since the solenoid valve 1 can drive the spool valve 7 to make the flow passage area of the flow passage 5 variable, the shock absorber D has an extension side damping force at the time of extension. Can be adjusted.

  In the solenoid valve 1, the inner diameter of the range H in which the spool port 7 a is provided from one end of the spool valve 7 is made larger than the inner diameter outside the range H, thereby reducing the thickness of the range H. The thin-walled portion 7b is provided.

  Since the spool port 7a is provided in the thin wall portion 7b in this way, when the spool port 7a is drilled in the spool valve 7 by laser processing, the laser output may be small and the amount of burrs generated is also reduced. Processing is also easy.

  Further, by providing the spool port 7a in the thin portion 7b, the area of the wall surface of the hole forming the spool port 7a is reduced. Therefore, even if the flow of the liquid passing through the port 6b and the spool port 7a becomes faster and the pressure decreases, the area of the wall surface receiving this pressure is small, so the spool valve 7 is moved upward in FIG. The force to be applied is small, and the influence of the solenoid 8 on the driving of the spool valve 7 is small. This will be described in more detail below. First, when the wrap area (overlapping area) between the annular groove 6c and the spool port 7a is reduced, the flow of the liquid becomes faster if the flow rate is the same, and the pressure becomes lower in the vicinity of this flow. When the wrap area between the annular groove 6c and the spool port 7a is reduced, a lower pressure in the lower side in FIG. 2 is closer to the flow in the wall surface forming the spool port 7a, and the upper side in FIG. A higher pressure acts on the side wall surface. Therefore, a high pressure acts on the above-described upper wall surface and a low pressure acts on the lower wall surface of the spool valve 7, and the force that moves the spool valve 7 upward in FIG. 2 acts as a whole. To do. That is, this force acts to move the spool valve 7 in a direction to reduce the lap area between the annular groove 6c and the spool port 7a. However, in the solenoid valve 1 of the present invention, since the spool port 7a is formed in the thin portion 7b, the height of the wall surface (the length in the left-right direction in FIG. 2) is low, and the thickness of the spool valve 7 is reduced. Compared with the case where the spool port is provided without change, the pressure receiving area for receiving these pressures is small, and the force for moving the spool valve 7 upward in FIG. 2 is small, so 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. Therefore, the solenoid valve 1 of the present invention is excellent in workability and can exhibit a stable damping force.

  Further, by setting the range H in which the thin portion 7b of the spool valve 7 is provided from one end of the spool valve 7 to the center in the axial direction, the range in which the thin portion 7b is provided is less than half the axial length of the spool valve 7. Can be economical.

  Further, the solenoid 8 includes a cylindrical stator S and an annular movable iron core 22 slidably inserted into the stator S, and the other end of the spool valve 7 is fitted into the movable iron core 22 so as to be integrated. Therefore, when the spool valve 7 is press-fitted into the movable iron core 22, the other end of the spool valve 7 which is not a thin wall portion 7b and sufficient in strength can be fixed to the movable iron core 22, The movable iron core 22 and the spool valve 7 can be firmly integrated.

  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 making the outer diameter of the movable iron core 22 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 adjust the flow path 5. When changing the flow path area, 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 to the shock absorber D during traveling of the vehicle slight.

  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 the pressure of the flow path 5 acts on the movable portion of the solenoid valve 1, the force that pushes the movable portion downward in FIG. 2 and the force that pushes the movable portion upward in FIG. The spool valve 7 does not move in any axial direction. Therefore, in the solenoid valve 1, even if the pressure of the flow path 5 becomes high, the adjustment of the flow area of the flow path 5 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 in the flow path 5 can be solved, and the damping force can be adjusted by driving the spool valve 7 with the small solenoid 8.

  From the above, since the spool valve 7 is not driven in the axial direction by the pressure of the flow path 5, the flow area of the flow path 5 is adjusted even if the force of attracting the movable iron core 22 of the solenoid 8 is small. The spool valve 7 that can reduce the cross-sectional area of the magnetic path in the movable iron core 22 and that does not affect the magnetic path can be made smaller in diameter than the movable iron core 22 and can be reduced in weight. Therefore, according to the solenoid valve 1 of the present invention, the damping force generated by the shock absorber D does not become the targeted damping force but vibrates due to the inputted vibration. Can be prevented. 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.

  In the solenoid valve 1 according to the present embodiment, an annular groove 6c that communicates with the port 6b and is opposed to the spool port 7a is provided on the inner periphery of the hollow portion 6a of the housing 6, and is annularly connected to the spool port 7a. Since the degree of communication between the port 6b and the spool port 7a is adjusted by the lap area of the groove 6c, there is no need to provide an annular groove in the spool valve 7, and the thickness of the thin portion 7b can be further reduced. Therefore, the force for moving the spool valve 7 when the liquid flows through the spool port 7a can be further reduced.

  Further, in the solenoid valve 1 of the present embodiment, a groove 22b is provided along the axial direction on the outer periphery of the movable iron core 22 so as to communicate the spool side chamber A and the anti-spool side chamber B. 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 22b on the outer periphery of the movable core 22 is easy to process. Compared with the case where the spool side chamber A is communicated with the spool valve 7 by providing a hole penetrating both the movable iron core 22 and the spool valve 7, the spool valve 7 Since positioning in the circumferential direction with respect to the movable iron core 22 is unnecessary, assembly is also simplified.

  In the above description, the outer diameter of the movable iron core 22 is single, but the section from the base side end to the part in contact with the inner periphery of the base side end of the inner cylinder 30a of the case 30 in the state where the movable core 22 is seated on the base 33. If the area does not cause saturation of the magnetic flux density, the wall thickness on the spool valve side can be made thinner than that on the base side, and the outer diameter on the spool valve side can be made smaller than that part. Thus, the overall weight of the movable part of the solenoid valve 1 may be further reduced. In this case, for example, as shown in FIG. 3, the outer diameter of the movable iron core 22 on the side opposite to the spool and always in sliding contact with the inner periphery of the inner cylinder 30 a is larger than the outer diameter of the spool valve 7. The outer diameter on the spool valve side of the larger diameter portion 22c is smaller than the larger diameter portion 22c. A smaller diameter portion 22d is provided, and the smaller diameter portion 22d is fitted to the inner periphery of the spool valve 7. It is also possible to integrate both. In this case, since the weight of the heavy movable iron core 22 can be further reduced, the overall weight of the movable portion of the solenoid valve 1 can be further reduced. For communication between the spool side chamber A and the anti-spool side chamber B, a groove 22e may be provided on the outer periphery of the large diameter portion 22c.

  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. A space L formed by the vehicle body side tube 10 and the axle side tube 11 by connecting the piston rod 4 to the vehicle body side tube 10 via the connected housing 6 and connecting the cylinder 2 to the axle side tube 11. A reservoir R is formed inside the space L and outside the shock absorber D, and the flow path 5 passes through the piston rod 4 so that the pressure side chamber R2 or the extension side chamber R1 in the cylinder 2 and the hollow portion of the housing 6 are accommodated. 6a is communicated, and the port 6b is communicated to 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.

  The shock absorber D includes a hole 4b in which the piston rod 4 forms a part of the flow path 5 along the axial direction, and the piston rod 4 and the housing 6 connected to the tip of the piston rod 4 are hollow. The portion 6a and the hole 4b are connected so as to be coaxial and 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 is configured such that the flow path 5 allows the passage of the liquid only when the shock absorber D is extended, and the damping force that generates the expansion side damping force of the shock absorber D. Since it functions as a generating element, the expansion side damping force of the shock absorber D can be adjusted, but the flow path 5 is set to allow 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 generation element that generates the compression side damping force of the shock absorber D. That is, if the pressure side chamber R2 is communicated to the hollow portion 4b instead of the expansion side chamber R1 through the communication passage 4d provided in the piston coupling portion 4c, the solenoid valve 1 can adjust the compression side damping force. If it does in this way, it can set up so that a liquid may pass through channel 5 only at the time of contraction operation of buffer D.

  Further, when the flow path 5 is set so as to communicate the expansion side chamber R1 and the pressure side chamber R2, the solenoid valve 1 adjusts the damping force both when the shock absorber D is extended and contracted. It may be set. 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. Just do it.

  Further, in the above description, the flow path area of the flow path 5 is set to decrease when the spool valve 7 is retracted. However, the spool valve 7 is set at the lowest position so that the flow path area of the flow path 5 is minimized. The flow path area of the flow path 5 may be increased by retreating the spool valve 7 or the flow path 5 may be completely blocked. .

  Further, the housing 6 may be integrated with the piston rod 4 to be a single component, or the housing 6 may be constituted by a plurality of components. 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 Flow path 6 Housing 6a Hollow part 6b Port 6c Annular groove 7 Spool valve 7a Spool port 7b Thin part 8 Solenoid 22 Movable iron core A Spool side chamber B Anti-spool side chamber D Buffer R1 Extension side chamber R2 Pressure side Chamber S Stator

Claims (7)

Slidably inserted axially with the housing, with a spool port for communicating the inside and outside a tubular within the hollow portion and a port opening from the hollow portion and the outwardly communicated to the hollow portion A solenoid valve capable of adjusting the degree of communication between the port and the spool port by driving the spool valve, from one end of the spool valve. A solenoid valve characterized in that a thin portion having a thickness thinner than outside the above range is provided at least in a range where the spool port is provided.   2. The solenoid valve according to claim 1, wherein the range in which the thin portion is provided is a range within one axial center from one end of the spool valve. And wherein said solenoid and a movable iron core of an annular that is slidably inserted into the cylindrical stator and the stator, and integrated fitted and the other end of the spool valve to the movable within core The solenoid valve according to claim 1 or 2.   The outer diameter of the movable iron core is larger than the outer diameter of the spool valve, and the movable iron core communicates the spool side chamber and the anti-spool side chamber partitioned in the stator on the both axial sides of the movable iron core. The solenoid valve according to claim 3.   An annular groove that communicates with the port and is opposed to the spool port is provided on the inner periphery of the hollow portion of the housing, and the degree of communication between the port and the spool port is adjusted by the lap area of the spool port and the annular groove. The solenoid valve according to any one of claims 1 to 4, wherein: Range inside diameter of providing the thin portion of the spool valve according to any one of claims 1 to 5, characterized in that a said thin portion by a diameter larger than the inner diameter outside the above range Solenoid valve. 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, with a flow channel allowing the passage of liquid in one or both during contraction and elongation at, and a solenoid valve according to one of claim 1 to 6 provided in the middle of the flow path Shock absorber.

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