JP2008008390A - Hydraulic shock absorber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic shock absorber for preventing the sink of a body of an bicycle when started, while absorbing a great input such as abnormal upthrust acting on a wheel. <P>SOLUTION: The hydraulic shock absorber 10 comprises an on-off valve 80 provided on a communication passage 57 between oil chambers 38A, 38B of a cylinder 11 and a damping force generation part 60 for shutting off the communication passage 57 by external electric operation, a bypass line 58 for bypassing the damping force generation part 60 and the on-off valve 80 and making the oil chambers 38A, 38B of the cylinder 11 communicate with a reservoir 51, and a blow valve 100 provided on the bypass passage 58. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a hydraulic shock absorber that is interposed between a vehicle body such as a bicycle or a motorcycle and wheels to absorb an impact from a road surface.

  The hydraulic shock absorber described in Patent Document 1 generates a damping force when oil passes through a passage communicating the damper main body and the reservoir and adjusts the generated damping force by adjusting the level of the generated damping force by inputting an external electrical signal. Part.

In the hydraulic shock absorber described in Patent Document 2, a manual adjustment unit that adjusts the amount of oil passing through the orifice in a passage that communicates the damper main body and the reservoir, and a bypass path that bypasses the manual adjustment unit from the outside It is assumed that an automatic adjustment unit that adjusts the amount of oil passing through the bypass passage by inputting the electrical signal is provided.
JP2001-304325 JP2001-294027

  According to the hydraulic shock absorber of Patent Document 1, when a rider depresses a pedal strongly at the start of a bicycle or the like, the damping force can be adjusted to be high with respect to the input from the rider or the drive chain, and the vehicle body can be prevented from sinking. However, in the state where the damping force is adjusted to be high, if there is a large input such as an abnormal push-up on the wheel, the hydraulic shock absorber is locked, and the vehicle body may fall over or the hydraulic shock absorber may be damaged.

  In the hydraulic shock absorber of Patent Document 2, even if the automatic adjustment unit is closed at the start of a bicycle or the like, the orifice constituting the manual adjustment unit allows the oil to flow, so that the sinking of the vehicle body cannot be prevented. Further, when there is a large input such as an abnormal push-up on the wheel, the large input cannot be absorbed only by the orifice constituting the manual adjustment unit.

  SUMMARY OF THE INVENTION An object of the present invention is to prevent a vehicle body from sinking and absorb a large input such as an abnormal push-up acting on a wheel at the start of a bicycle or the like in a hydraulic shock absorber.

  According to the first aspect of the present invention, a piston rod is inserted into the oil chamber of the cylinder, and a reservoir that compensates for the volume of the piston rod that advances and retreats into the oil chamber of the cylinder is communicated with the oil chamber of the cylinder through the communication path. In a hydraulic shock absorber provided with a force generation part, an on-off valve is provided on the communication path between the cylinder oil chamber and the damping force generation part to shut off the communication path by external electrical operation, thereby generating damping force. And a bypass passage that connects the cylinder and the oil chamber to the reservoir, and a blow valve is provided on the bypass passage.

  According to a second aspect of the present invention, in the first aspect of the present invention, the blow valve further includes a valve opening pressure adjusting portion.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the on-off valve is shut off for a predetermined time by an electric operation from the outside.

(Claim 1)
(a) When the rider strongly depresses the pedal at the start of a bicycle, etc., if the open / close valve is electrically operated from the outside to shut off the communication path of the damping force generation part, the flow path of the damping force generation part is completely blocked. This eliminates the fluffiness of the hydraulic shock absorber against the input from the rider or drive chain, and prevents the body from sinking.

  (b) In the state where the on-off valve of (a) mentioned above shuts off the communication path of the damping force generation unit, when there is a large input such as abnormal pushing up on the wheel, the blow valve opens and abnormal high pressure in the cylinder opens to the reservoir. Miss and absorb large input. As a result, it is possible to avoid the vehicle body falling or the hydraulic shock absorber from being damaged due to a large input. Since the blow valve is not related to the riding comfort during normal running, an appropriate blow pressure sufficient to absorb the above-described large input can be set.

  (c) During normal traveling of a bicycle or the like, the blocking of the communication path by the on / off valve of (a) above is released, and the damping force generator generates a damping force of an appropriate magnitude. The damping force generator can set an appropriate damping force considering only the riding comfort during normal driving.

(Claim 2)
(d) The above-described blow pressure (b) of the blow valve can be appropriately adjusted by the valve opening pressure adjusting section. The riding style can be selected according to the rider's preference, or it can be adjusted according to the road surface condition.

(Claim 3)
(e) The on / off valve of the above (a) is interlocked with a timer, and the on / off valve is shut off for a certain time by an external electric operation, so that only when the vehicle speed of the bicycle or the like increases from the start to a certain speed (for example, (Set the timer to 5 seconds) Disabling the flow path of the damping force generation unit, and then automatically generating the normal damping force (c) set in the damping force generation unit to ensure steering stability .

  1 is a plan view showing a hydraulic shock absorber, FIG. 2 is a sectional view taken along line II-II in FIG. 1, FIG. 3 is a sectional view taken along line III-III in FIG. 5 is a cross-sectional view showing the damping force generator and the on-off valve in FIG. 2, FIG. 6 is a cross-sectional view showing the blow valve in FIG. 3, and FIG. 7 is a block diagram showing the control system.

  As shown in FIGS. 1 to 3, the hydraulic shock absorber 10 includes a hollow piston rod 12 inserted into a cylinder 11 and a suspension spring 13 interposed between the cylinder 11 and the outside of the piston rod 12.

  The cylinder 11 includes a vehicle body side mounting member 14, and the piston rod 12 includes a wheel side mounting member 15. A spring receiver adjustment ring 16 is screwed to the outer peripheral portion of the cylinder 11 with a spring receiver 17, and a spring receiver 18 is fixed to the piston rod 12. A suspension spring 13 is interposed between the spring receiver 17 and the spring receiver 18. And the set length of the suspension spring 13 can be adjusted by screwing the spring receiving adjustment ring 16. The elastic force of the suspension spring 13 absorbs the impact force that the vehicle receives from the road surface.

  The cylinder 11 includes a rod guide 21 through which the piston rod 12 passes. The rod guide 21 is liquid-tightly attached to the cylinder 11 via an O-ring 22 and allows the piston rod 12 to slide in a liquid-tight manner on an inner diameter portion including an oil seal 23, a bush 24 and a dust seal 25. The cylinder 11 is provided with a pressure side bumper 26 outside the rod guide 21, and at the time of maximum compression, the pressure side bumper 26 is abutted against a bumper stopper 27 provided in the piston rod 12 so that the maximum compression stroke can be regulated. Further, the cylinder 11 includes a washer 28 and an extension side bump rubber 29 inside the rod guide 21.

  The hydraulic shock absorber 10 includes a piston valve device (extension-side damping force generation device) 30 and a base valve device (compression-side damping force generation device) 50. The hydraulic shock absorber 10 suppresses expansion and contraction vibration of the cylinder 11 and the piston rod 12 due to the absorption of the impact force by the suspension spring 13 by the damping force generated by the piston valve device 30 and the base valve device 50.

(Piston valve device 30) (FIG. 4)
As shown in FIGS. 2 to 4, the piston valve device 30 has a hollow piston bolt 31 screwed onto the end of the piston rod 12 inserted into the cylinder 11, and a piston 32 and a first pressure side plate valve 33 </ b> A. The second pressure side plate valve 33B, the extension side plate valve 34A, and the valve stopper 35 are inserted and fixed with nuts 36.

  The piston 32 is provided with an O-ring 37A and a piston ring 37B on the outer periphery, and slidably contacts the inside of the cylinder 11. The piston-side oil chamber 38A in which the piston rod 12 is not housed and the rod in which the piston rod 12 is housed. The side oil chamber 38B is partitioned. The piston 32 includes a first pressure side plate valve 33A for damping at low speed and a second pressure side plate valve 33B for deceleration at high speed, and allows the piston side oil chamber 38A and the rod side oil chamber 38B to communicate with each other. 33 and an expansion side flow path 34 that includes an expansion side plate valve 34A and allows the piston side oil chamber 38A and the rod side oil chamber 38B to communicate with each other.

  The piston valve device 30 has a damping force adjusting device 40. As shown in FIG. 4, the damping force adjusting device 40 passes a damping force adjusting rod 42 operated by the slider device 41 through the hollow portions of the piston rod 12 to the piston bolt 31 so as to freely advance and retract, and a needle at the tip of the adjusting rod 42. The valve 43 enables adjustment of the opening area of the bypass flow path 44 between the piston-side oil chamber 38A and the rod-side oil chamber 38B provided in the piston bolt 31.

  The slider device 41 includes an adjustment holder 45 that is press-fitted and fixed to the wheel side mounting portion 15 of the piston rod 12 from a direction orthogonal to the axial direction of the piston rod 12, an adjuster 46 that is pivotally attached to the adjustment holder 45, and an adjuster. A ball 48 that is urged by a set spring 47 in a direction perpendicular to the axis 46 and engageable with an engagement recess on the side of the adjustment holder 45, and a slider 49 that is screwed to the threaded portion of the adjuster 46. Is done. The adjuster 46 is supported by the adjustment holder 45 on the operation end side provided with the dial 46A, is supported by the wheel side mounting portion 15 on the counter-operation end side, and is rotated by the dial 46A, so that the ball 48 is positioned at a plurality of positions in the circumferential direction of the adjustment holder 45. The adjuster 46 can be engaged with each of the engaging recesses arranged (equally arranged) in order, and the adjuster 46 can be set to the rotational operation stop position with a sense of moderation. On the other hand, the slider 49 is guided by a guide 15A provided on the wheel side mounting portion 15 so as to be reciprocally movable in the axial direction while being screwed to the screw portion of the adjuster 46. As a result, the slider device 41 can move the slider 49 forward and backward in a direction orthogonal to the axial direction of the adjustment rod 42 by rotating the adjuster 46.

  The tip needle valve 43 of the adjustment rod 42 is liquid-tightly inserted into the hollow portion of the piston rod 12 via the O-ring 43 </ b> A, and adjusts the opening area of the bypass channel 44. At this time, the adjustment rod 42 is brought into pressure contact with the tapered surface 49A of the slider 49 by the thrust force based on the hydraulic pressure of the piston-side oil chamber 38A of the cylinder 11.

  That is, in the piston valve device 30, the taper surface 49 </ b> A of the slider 49 is brought into contact with the proximal end rod end 42 </ b> A of the adjustment rod 42, and the slider 49 is operated based on a rotation operation applied to the dial 46 </ b> A of the adjuster 46 of the slider device 41. The adjustment rod 42 is advanced and retracted in the axial direction by advance and retreat, and the opening area of the bypass flow path 44 is adjusted by the movement of the needle valve 43 at the tip of the adjustment rod 42.

  In the bypass passage 44 of the piston bolt 31, a ball valve 31 </ b> B that is prevented from coming off by a pin 31 </ b> A that is pierced in the radial direction of the piston bolt 31 can be seated at an opening end facing the piston-side oil chamber 38 </ b> A. Thus, only the flow from the rod side oil chamber 38B to the piston side oil chamber 38A is allowed in the bypass flow path 44. Thereby, the damping force adjusting device 40 operates only in the extension stroke of the hydraulic shock absorber 10.

  Therefore, when the hydraulic shock absorber 10 is compressed, the oil in the piston side oil chamber 38A passes through the pressure side flow path 33, and when the relative speed between the cylinder 11 and the piston rod 12 is low, the first pressure side plate valve 33A is bent and deformed. It flows into the side oil chamber 38B and obtains a compression side damping force. Further, when the relative speed between the cylinder 11 and the piston rod 12 is high, the oil in the piston side oil chamber 38A bends and deforms the second pressure side plate valve 33B and flows into the rod side oil chamber 38B to obtain a compression side damping force.

  Further, when the hydraulic shock absorber 10 is extended, when the relative speed between the cylinder 11 and the piston rod 12 is low, the oil in the rod side oil chamber 38B passes through the bypass flow path 44 with the needle valve 43 to the piston side oil chamber 38. The expansion side damping force is generated by the throttle resistance of the needle valve 43 during the flow. This damping force is adjusted by rotating the adjuster 46 of the slider device 41.

  When the hydraulic shock absorber 10 is extended and the relative speed between the cylinder 11 and the piston rod 12 is medium to high, the oil in the rod side oil chamber 38B passes through the extension side flow path 34 to bend and deform the extension side valve 34A. It is guided to the piston side oil chamber 38A and produces an extension side damping force.

(Base valve device 50) (FIG. 5)
In the base valve device 50, a reservoir 51 is integrated with the cylinder 11, and an oil chamber 54 and a gas chamber 55 are sealed by a diaphragm type (or a free piston type) partition member 53 inside the reservoir 51 sealed with a cap 52. It is divided into and. The cap 52 is provided with a gas filling valve 56 that fills the gas chamber 55 with pressurized gas.

  As shown in FIG. 5, the base valve device 50 is provided with a communication passage 57 that connects the oil chambers 38 </ b> A and 38 </ b> B of the cylinder 11 to the oil chamber 54 of the reservoir 51 at the connecting portion of the cylinder 11 and the reservoir 51. The volume of the piston rod 12 entering / exiting the chambers 38 </ b> A and 38 </ b> B is compensated by the reservoir 51, and a damping force generator 60 is provided in the communication path 57.

  As shown in FIG. 5, the damping force generator 60 is provided with a valve housing 61 in a communication region between the piston side oil chamber 38 </ b> A of the cylinder 11 and the oil chamber 54 of the reservoir 51, and a plug bolt screwed to the cylinder 11. The valve housing 61 is fixed by 62. A piston 63 is fixed to the valve housing 61, and a flow path 64 is provided in the piston 63. A bypass forming bolt 65 is fixed to the center of the piston 63 by a nut 66, and a pressure side valve 67 that opens the passage 64 when compressed is provided around the center of the bypass forming bolt 65, and the passage 64 is electrically connected when extended. An extension side valve (check valve) 68 is provided.

  The damping force generator 60 is rotatably attached to an adjustment rod 71 having a dial 71A on a plug bolt 62. The needle valve can be engaged with the distal end of the adjustment rod 71 in the rotational direction and relatively moved in the axial direction. 72, and an outer peripheral thread portion of the needle valve 72 is screwed to a nut 73 that is crimped and fixed to the distal end side of the plug bolt 62. The adjustment rod 71 includes a ball 75 that is urged by a set spring 74 in the axially outward direction of the adjustment rod 71 and can be engaged with the engagement recess of the plug bolt 62. As a result, the needle valve 72 is moved back and forth with respect to the bypass passage 65A of the bypass forming bolt 65, and the opening area of the bypass passage 65A can be adjusted.

  Therefore, when the hydraulic shock absorber 10 is compressed in the normal operation state, the oil corresponding to the volume of the piston rod 12 that has entered the cylinder 11 flows from the piston-side oil chamber 38A to the bypass passage 65A of the bypass forming bolt 65 or the piston 63. Is discharged to the oil chamber 54 of the reservoir 51. At this time, when the speed is low, a compression-side damping force is obtained by the throttle resistance of the needle valve 72 provided in the bypass flow path 65A. This damping force is adjusted by the adjusting rod 71. Further, at medium and high speeds, the oil passing through the flow path 64 from the piston side oil chamber 38A bends and deforms the pressure side valve 67 and is guided to the oil chamber 54 of the reservoir 51 to generate a pressure side damping force.

  When the hydraulic shock absorber 10 is extended, the oil corresponding to the retraction volume of the piston rod 12 retreating from the cylinder 11 is returned from the oil chamber 54 of the reservoir 51 to the piston side oil chamber 38A through the expansion side valve 68 and the flow path 64. The

  As shown in FIG. 5, the base valve device 50 opens and closes on the communication path 57 between the piston-side oil chamber 38 </ b> A of the cylinder 11 and the damping force generation unit 60 to block the communication path 57 by an external electric operation. A valve 80 is provided.

  The on-off valve 80 is slidably loaded in the axial direction of the valve chamber 81 provided across the intermediate portion of the communication passage 57 in the cylinder 11 and is screwed to the open end side of the valve chamber 81 to connect the O-ring 84A. A perforated cap 82 that is fixed through a through hole is inserted through an O-ring 84 </ b> B, and a coil spring 83 (not shown) is interposed between the closed end of the valve chamber 81 and the on-off valve 80. At the standby position where the on / off valve 80 is pressed against the cap 82 by the biasing force of the coil spring 83 (the left half of the on / off valve 80 in FIG. 5), the on / off valve 80 moves away from the valve seat 81 </ b> A and communicates on both sides of the valve chamber 81. 57 and 57 are conducted. The on-off valve 80 is slidably contacted with the valve chamber 81 and can be pushed and moved from the standby position to the shut-off work position in the direction in which the coil spring 83 is pressurized (the right half of the on-off valve 80 in FIG. 5). The passage 57 is blocked.

  The electromagnetic solenoid 90 is screwed to the mounting plate 91, covered with a cover 92 that is bolted to the cylinder 11 together with the mounting plate 91, and is fixed to the cylinder 11. As shown in FIG. 7, the electromagnetic solenoid 90 is excited by a controller 94 that receives an ON signal of the pushbutton switch 93 to cause the plunger 90A to protrude, and the on-off valve 80 on which the plunger 90A is coaxially abutted is placed on the above-described standby state. Push from the position to the blocking work position. A power supply terminal 95 is connected to a battery or a DC power source. The controller 94 excites the electromagnetic solenoid 90 as described above for a predetermined time set in the built-in timer, and shuts off the communication path 57 by the on-off valve 80 for the predetermined time. After the elapse of the predetermined time, the electromagnetic solenoid 90 is demagnetized, and the on-off valve 80 is automatically returned to the standby position by the biasing force of the coil spring 83. The coil spring 83 may not be provided.

  As shown in FIG. 1, the base valve device 50 bypasses the damping force generator 60 and the on-off valve 80 at the connecting portion between the cylinder 11 and the reservoir 51, and the oil chambers 38 </ b> A and 38 </ b> B of the cylinder 11 and the oil chamber 54 of the reservoir 51. And a blow valve 100 is provided on the bypass path 58.

  As shown in FIG. 6, the blow valve 100 has an adjustment holder 101 inserted into the cylinder 11 via an O-ring 101 </ b> A screwed thereto, and an adjuster 102 is pivotally supported on the adjustment holder 101 via an O-ring 102 </ b> A. A ball 104 which is urged by a set spring 103 in a direction perpendicular to the axis of the shaft 104 so as to be engageable with an engagement concave portion on the side of the adjustment holder 101 is provided, and a spring which is coaxially engaged with the adjuster 102 and is engaged with the concave and convex portions in the rotational direction. The presser 105 is screwed to the cylinder 11, and the ball-shaped valve body 107 backed up by the compression spring 106 supported by the spring presser 105 is pressed against the valve seat 108 </ b> A of the valve chamber 108 provided in the middle portion of the bypass passage 58. The bypass passage 58 communicating with the eleventh oil chamber 38A is closed. When the oil pressure in the oil chamber 38A reaches a certain blow pressure exceeding the biasing force of the spring 106, the valve body 107 moves away from the valve seat 108A and opens the bypass passage 58. The adjuster 102 includes a dial 109 (valve opening pressure adjusting unit). The adjuster 102 is rotated by the dial 109, and the balls 104 are sequentially engaged with the engaging recesses arranged (equally arranged) at a plurality of positions in the circumferential direction of the adjust holder 101, and the adjusters 102 are stopped at their rotation operation stop positions. The setting is changed with a sense of moderation. The blow valve 100 adjusts the spring force of the spring 106 by adjusting the spring force of the spring 106 by rotating the spring retainer 105 in the axial direction by a rotational operation applied to the dial 109 of the adjuster 102, thereby generating a blow pressure (valve opening pressure). Make it adjustable.

  However, the hydraulic shock absorber 10 prevents the vehicle body from sinking as follows when starting a bicycle or the like.

  (1) When the rider turns on the pushbutton switch 83, the controller 84 closes the on-off valve 80 for a certain period of time as described above, the communication path 57 is shut off, and as a result, the flow path of the damping force generator 60 is When the pedal is depressed by the rider, the hydraulic shock absorber 10 can be eliminated and the vehicle body can be prevented from sinking. It can be used for traveling a bicycle or the like without losing the rider's tension.

  (2) When a large input such as an abnormal push-up is applied to a wheel of a bicycle or the like, the blow valve 100 of the bypass passage 58 is opened to allow the oil flow and absorb the large input. Thereby, the fall of the vehicle body caused by the large input or the breakage of the hydraulic shock absorber 10 can be avoided.

According to the present embodiment, the following operational effects can be obtained.
(a) When the rider strongly depresses the pedal at the start of a bicycle or the like, the flow path of the damping force generating unit 60 can be obtained by electrically operating the on-off valve 80 from the outside to block the communication path 57 of the damping force generating unit 60. Is completely disconnected, eliminating the fluffiness of the hydraulic shock absorber against the input from the rider or drive chain, and preventing the body from sinking.

  (b) In the state where the on-off valve 80 of (a) described above shuts off the communication passage 57 of the damping force generating unit 60, when there is a large input such as abnormal pushing up on the wheel, the blow valve 100 is opened and the inside of the cylinder 11 is opened. Abnormally high pressure is released to the reservoir 51 to absorb large input. As a result, it is possible to avoid the vehicle body falling or the hydraulic shock absorber from being damaged due to a large input. Since the blow valve 100 is not related to the riding comfort during normal running, an appropriate blow pressure sufficient to absorb the large input described above can be set.

  (c) During normal traveling of a bicycle or the like, the shutoff of the communication path 57 by the on-off valve 80 described in (a) above is released, and the damping force generator 60 generates a damping force of an appropriate magnitude. The damping force generator 60 can set an appropriate damping force considering only the riding comfort during normal driving.

  (d) The above-described blow pressure (b) of the blow valve 100 can be appropriately adjusted by the valve opening pressure adjusting portion (dial 109). The riding style can be selected according to the rider's preference, or it can be adjusted according to the road surface condition.

  (e) The on / off valve 80 of the above (a) is interlocked with a timer, and the on / off valve 80 is shut off for a predetermined time by an external electric operation, so that the vehicle speed of a bicycle or the like increases only from the start to a constant speed. (For example, a timer is set to 5 seconds) The flow path of the damping force generation unit 60 is blocked, and thereafter, the normal damping force of the above-described (c) set in the damping force generation unit 60 is automatically generated to stabilize the operation. Can be secured.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration of the present invention is not limited to this embodiment, and even if there is a design change or the like without departing from the gist of the present invention. It is included in the present invention.

FIG. 1 is a plan view showing a hydraulic shock absorber. FIG. 2 is a sectional view taken along line II-II in FIG. FIG. 3 is a sectional view taken along line III-III in FIG. FIG. 4 is a cross-sectional view showing the piston valve device. FIG. 5 is a cross-sectional view showing the damping force generator and the on-off valve of FIG. 6 is a cross-sectional view showing the blow valve of FIG. FIG. 7 is a block diagram showing the control system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Hydraulic buffer 11 Cylinder 12 Piston rod 38A, 38B Oil chamber 51 Reservoir 57 Communication path 58 Bypass path 60 Damping force generation part 80 On-off valve 90 Solenoid 93 Pushbutton switch 94 Controller 100 Blow valve

Claims (3)

A piston rod is inserted into the oil chamber of the cylinder, a reservoir that compensates for the volume of the piston rod that advances and retreats into the oil chamber of the cylinder is communicated with the oil chamber of the cylinder through a communication path, and a damping force generation unit is provided in the communication path. In hydraulic shock absorber,
An open / close valve is provided on the communication path between the oil chamber of the cylinder and the damping force generator to shut off the communication path by an external electric operation.
A hydraulic shock absorber, characterized in that a bypass passage that bypasses the damping force generation section and the on-off valve, communicates between the oil chamber of the cylinder and the reservoir is provided, and a blow valve is provided on the bypass passage.   The hydraulic shock absorber according to claim 1, wherein a valve opening pressure adjusting portion is provided in the blow valve.   The hydraulic shock absorber according to claim 1 or 2, wherein the on-off valve is shut off for a predetermined time by an electric operation from the outside.

Images