JP5330003B2 - Shock absorber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact and lightweight shock absorber capable of varying damping forces at elongation and contraction sides and reducing cost. <P>SOLUTION: The shock absorber D includes: a cylinder 1; a piston 2 slidably inserted into the cylinder 1 and partitioning the inside of the cylinder 1 into one chamber R1 and the other chamber R2; an electromagnetic relief valve 4; and a direction switching valve 5 which has one communication position 5b connecting the one chamber R1 to the upstream side of the electromagnetic relief valve 4 and connecting the other chamber R2 to the downstream side of the electromagnetic relief valve 4, and the other communication position 5c connecting the other chamber R2 to the upstream side of the electromagnetic relief valve 4 and connecting the one chamber R1 to the downstream side of the electromagnetic relief valve 4 which is switched to the one communication position 5b when pressure in the one chamber R1 exceeds pressure in the other chamber R2 with pressure in the one chamber R1 and other chamber R2 regarded as pilot pressure, and is switched to the other communication position 5c when pressure in the other chamber R2 exceeds pressure in the one chamber R1. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an improved shock absorber.

  For example, this type of shock absorber is interposed between a vehicle body and an axle of a motorcycle or between a steering wheel and a vehicle body of a motorcycle to dampen vibrations in a vibration control target. In such a shock absorber, it may be desired that the damping force generated during expansion and compression can be made variable independently.

  In order to satisfy such a requirement, for example, there are provided an expansion side damping valve that exhibits a damping force when the shock absorber is extended and a compression side damping valve that exhibits a damping force when compressed, and these are driven by a solenoid. The generated damping force can be made variable.

  However, when each of the expansion side and compression side damping valves is driven by separate solenoids, two solenoids are required for one shock absorber, which increases the size of the shock absorber and increases its weight and cost.

  In order to avoid this, there is a proposal that controls the valve body of both the expansion side damping valve and the pressure side damping valve in series and controls them with a single solenoid. The damping force can be adjusted, and the increase in size, weight, and cost of the shock absorber can be reduced (see, for example, Patent Documents 1 and 2).

JP 2006-183864 A JP 2008-256205 A

  In the above proposal, it is possible to control the damping valve on the expansion side and the compression side with one solenoid, but it is necessary to take a large stroke of the solenoid to control the two damping valves. Although it is lighter, smaller, and less expensive than a shock absorber that must be provided, the solenoid itself is increased in size, so further reduction in size, weight, and cost reduction are desired.

  Accordingly, the present invention was devised in order to improve the above-described problems, and the object of the present invention is to provide a buffer that can make the damping force on the extension side and the compression side variable and can be reduced in size, weight, and cost. Is to provide a vessel.

To achieve the above object, the damper in problem-solving means of the present invention includes a cylinder, a piston for partitioning the interior of the cylinder and the one chamber and the other chamber with inserted slidably into the cylinder, connecting the electromagnetic relief valve for imparting a damping force to the working fluid the hand chamber and flows out from the other chamber, the other chamber with connecting the one chamber to the upstream of the electromagnetic relief valve downstream of the electromagnetic relief valve while the side connecting positions and the other chamber and a directional control valve for chromatic and other side connecting positions for connecting the one chamber with connection to the upstream of the electromagnetic relief valve downstream of the solenoid relief valve, the direction of switching valve, pressure in the one chamber the pressure of the hand chamber and the other chamber during movement within the cylinder of the piston as the pilot pressure is above Above the pressure of the square chamber switched to the one-side connecting positions, the pressure of the other chamber, characterized in that the Waru switching to the other side connecting positions exceeds the pressure in the one chamber.

  According to the shock absorber of the present invention, the damping force on both the expansion side and the compression side can be made variable using a single electromagnetic relief valve, and the expansion side is controlled by the solenoid of the electromagnetic relief valve. Because it is a single relief valve instead of the two damping valves on the compression side, the stroke of the solenoid does not become long, the shock absorber can be made smaller and lighter, and further the cost can be reduced Can do.

  In addition, the direction switching valve can adopt a simple structure, and since the pressure in one chamber and the other chamber operates as a pilot pressure and does not need to be driven by a solenoid, the size of the shock absorber is increased by installing the direction switching valve. Will not be invited.

It is a circuit diagram in the buffer in one embodiment. It is the figure which showed a specific example of the direction switching valve. It is the figure which showed the other specific example of the direction switching valve. It is a circuit diagram in the buffer in 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, a shock absorber D in one embodiment includes a cylinder 1 and a piston 2 that is slidably inserted into the cylinder 1 and that partitions the cylinder 1 into one chamber R1 and the other chamber R2. And an electromagnetic relief valve 4 provided in the middle of the damping flow path 3 communicating the one chamber R1 and the other chamber R2, and in the middle of the damping flow path 3 so as to straddle the upstream and downstream of the electromagnetic relief valve 4. The direction switching valve 5 is provided.

  Hereinafter, each part will be described in detail. Both ends of the cylinder 1 are closed by the lids 6 and 7, and a piston 2 that is allowed to slide in the left-right direction in FIG. Thus, the inside of the cylinder 1 is partitioned into one chamber R1 and the other chamber R2. The one chamber R1 and the other chamber R2 are filled with a working fluid. As the working fluid, it is possible to use a gas in addition to a liquid such as a working oil.

  In addition, the piston 2 is provided in the middle of a rod 8 that is pivotally supported by lids 6 and 7 that close both ends of the cylinder 1 and is movably inserted into the cylinder 1. The outer diameter of the rod 8 is constant, and the rod 8 is set to a double rod type in which the total volume of the one chamber R1 and the other chamber R2 does not change even if the piston 2 moves in the left-right direction within the cylinder 1. It is also possible to set different outer diameters for the one chamber R1 side and the other chamber R2 side. The shock absorber D can be used as a steering damper, for example, by connecting to the handle of the motorcycle via the left end mounting portion 8a of the rod 8 and connecting the cylinder 1 to the vehicle body of the motorcycle.

  Further, ports 1 a and 1 b are provided on the side of the cylinder 1, and these ports 1 a and 1 b are communicated with each other through the damping flow path 3 described above. The ports 1a and 1b may be provided not on the cylinder 1 but on the lids 6 and 7.

  The electromagnetic relief valve 4 provided in the middle of the damping flow path 3 has the lower side in FIG. 1 as the upstream side, the valve body 4a, and the direction in which the upstream side pressure is guided to one end of the valve body 4a to open the valve body 4a. A pilot passage 4b that is actuated so as to be energized, and a solenoid 4c that exerts thrust opposite to the upstream pressure acting by the pilot passage 4b of the valve body 4a. The solenoid 4c is proportional to the energization amount. Thus, the relief pressure can be changed in accordance with the energization amount. The solenoid 4c may employ a push type that increases the thrust pushing the valve body 4a when the energization amount increases, or may employ a pull type that reduces the thrust pushing the valve body 4a when the energization amount increases. However, in order to generate a sufficient damping force even when there is a failure, a pull type may be employed.

  Subsequently, the direction switching valve 5 is a two-position, four-port switching valve, and is installed in the middle of the damping flow path 3 so as to straddle the upstream and downstream of the electromagnetic relief valve 4 described above. The one chamber R1 is connected upstream of the electromagnetic relief valve 4 and the other chamber R2 is connected downstream of the electromagnetic relief valve 4, and the other chamber R2 is connected upstream of the electromagnetic relief valve 4. A switching valve body 5a having the other side communication position 5c connecting the one chamber R1 downstream of the electromagnetic relief valve 4, a pilot passage 5d for applying the pressure of the one chamber R1 to one end of the switching valve body 5a, and the other chamber R2 And a pilot passage 5e that applies the pressure of the pressure to the other end of the switching valve main body 5a.

  In the direction switching valve 5, when the pressure in the one chamber R1 exceeds the pressure in the other chamber R2, the switching valve main body 5a is pressed rightward in FIG. 1 and switched to the one side communication position 5b. When the pressure exceeds the pressure in the one chamber R1, the switching valve main body 5a is pressed leftward in FIG. 1 and switched to the other side communication position 5c.

  Specifically, when the piston 2 moves to the left in FIG. 1 with respect to the cylinder 1, the direction switching valve 5 attenuates the working fluid from the compression-side one chamber R1 to the expansion-side other chamber R2. On the contrary, when the piston 2 moves to the right in FIG. 1 with respect to the cylinder 1, the working fluid is attenuated from the other chamber R 2 on the compression side toward the one chamber R 1 on the expansion side. The direction in which the working liquid flows through the attenuation flow path 3 is switched so that the liquid flows through the attenuation flow path 3.

  That is, in this shock absorber D, the higher one of the one chamber R1 and the other chamber R2 is selected and connected to the upstream side of the electromagnetic relief valve 4. An accumulator 9 is connected in the middle of the damping flow path 3 and downstream of the electromagnetic relief valve 4. The accumulator 9 absorbs a change in volume due to a temperature change of the working fluid and is connected to the one chamber R1. It is provided to pressurize the other chamber R2 so as not to be below atmospheric pressure.

  The direction switching valve 5 may adopt any configuration as long as it exhibits the above-described operation. As a specific configuration, for example, as shown in FIG. Is moved to one chamber R1 and the other end is communicated to the other chamber R2 and the stoppers 10a and 10b that are slidably inserted into the housing 10 and mounted in the housing 10 have a movement amount. The spool 11 to be regulated, the upstream port 12 provided in the housing 10 and connected to the upstream side of the electromagnetic relief valve 4, and the downstream side of the electromagnetic relief valve 4 provided at a position sandwiching the upstream port 12 of the housing 10 in the axial direction. Downstream ports 13, 14 connected to each other, a through hole 15 that opens from one end of the spool 11 to the side outer periphery, and opens from the other end of the spool 11 to the side outer periphery. It is constituted by a through hole 16.

  The spool 11 moves rightward in FIG. 2 and contacts the stopper 10b. When the through hole 15 communicates with the upstream port 12, the through hole 16 communicates with the downstream port 14, and the spool 11 contacts the stopper 10a. When the through hole 15 communicates with the downstream port 13 in the position shown in FIG. 2, the through hole 16 communicates with the upstream port 12. In addition, the housing 10 is provided with separate ports communicating with the one chamber R1 and the other chamber R2, and when the through hole 15 communicates with the upstream port 12, the downstream port 14 and the port communicated with the other chamber R2 are provided. The annular groove provided on the outer periphery of the spool 11 communicates with the annular groove provided on the outer periphery of the spool 11, and when the through hole 16 communicates with the upstream port 12, the downstream port 13 and the port communicated with the one chamber R 1 are connected to the annular groove provided on the outer periphery of the spool 11. You may make it communicate. Further, the communication of the through-hole 15 and the through-hole 16 to the respective ports 12, 13, and 14 is performed via an annular groove provided on the outer periphery of the spool 11. Even if they rotate in the direction, they do not become unable to communicate.

  Therefore, the direction switching valve 5 having this specific configuration exhibits the operation as described above, and connects the one chamber R1 and the other chamber R2 to the upstream side of the electromagnetic relief valve 4 on the high pressure side of the one chamber R1 and the other chamber R2. The low pressure side of the chamber R2 is connected downstream of the electromagnetic relief valve 4.

  As described above, the direction switching valve 5 can be configured with a simple configuration. In addition to this, as shown in FIG. 3, the housing 20 is hollow and has one end communicating with the one chamber R1 and the other end communicating with the other chamber R2, and is slidable within the housing 20. A cylindrical spool 21 that is inserted and restricted by the stoppers 20a and 20b mounted in the housing 20; an upstream port 22 provided in the housing 20 and connected upstream of the electromagnetic relief valve 4; A downstream port 23, 24 provided at a position sandwiching the upstream port 22 of the housing 20 in the axial direction and connected downstream of the electromagnetic relief valve 4, a pair of spheres 26, 27 and a sphere 26, accommodated in the spool 21, 27, a high-pressure priority valve 25 constituted by a spring 28 interposed between 27, a through-hole 29 communicating with the inside and outside of the spool 21, and the one chamber R1 and the housing 2 And the other port 31 provided on the same circumference as the downstream port 24 of the housing 20 and communicated with the other chamber R2. .

  The through hole 29 always communicates with the upstream port 22 even if the spool 21 moves in the axial direction with respect to the housing 20, and when the spool 21 moves to the left with respect to the housing 20, one port 30 and downstream The port 23 communicates with an annular groove 21 a provided on the outer periphery of the spool 21, and when the spool 21 moves to the right with respect to the housing 20, the other port 31 and the downstream port 24 are provided with an annular groove 21 b provided on the outer periphery of the spool 21. It is designed to communicate with each other.

  The pressure of the one chamber R1 introduced from one end side of the housing 20 acts on one end of the spool 21, and the pressure of the other chamber R2 introduced from the other end side of the housing 20 acts on the other end of the spool 21. When a pressure difference is generated between the one chamber R1 and the other chamber R2, the high pressure side sphere 25 (26) of the spheres 25 and 26 is retracted, and the high pressure side of the one chamber R1 and the other chamber R2 is connected to the upstream port 22. It comes to communicate.

  Therefore, even in the direction switching valve 5 of this other specific configuration, the operation as described above is exhibited, and the high pressure side of the one chamber R1 and the other chamber R2 is connected to the upstream side of the electromagnetic relief valve 4, The low pressure side of the one chamber R1 and the other chamber R2 is connected downstream of the electromagnetic relief valve 4.

  The shock absorber D configured as described above compresses the one chamber R1 and expands the other chamber R2 when the rod 8 moves to the left with respect to the cylinder 1, and the pressure in the one chamber R1 is increased. Since the pressure in the other chamber R2 is higher than the pressure in the other chamber R2, the one chamber R1 in which the direction switching valve 5 is in a high pressure is connected upstream of the electromagnetic relief valve 4, and the other chamber R2 in which the pressure is low is connected downstream of the electromagnetic relief valve 4. Therefore, the working fluid in the one chamber R1 passes through the damping flow path 3 from the upstream side to the downstream side of the electromagnetic relief valve 4 and moves to the other chamber R2, thereby controlling the amount of current supplied to the solenoid 4c in the electromagnetic relief valve 4. Thus, the damping force on the extension side can be made variable.

  On the other hand, if the shock absorber D exhibits a compression operation in which the rod 8 moves to the right with respect to the cylinder 1, the other chamber R2 is compressed and the one chamber R1 is expanded, and the pressure in the other chamber R2 is Since the pressure is higher than the pressure, the other chamber R <b> 2 in which the direction switching valve 5 becomes high pressure is connected upstream of the electromagnetic relief valve 4, and the one chamber R <b> 1 in low pressure is connected downstream of the electromagnetic relief valve 4. Therefore, the working fluid in the other chamber R2 passes through the damping flow path 3 from the upstream side to the downstream side of the electromagnetic relief valve 4 and moves to the one chamber R1, thereby controlling the amount of current supplied to the solenoid 4c in the electromagnetic relief valve 4. Thus, the compression side damping force can be made variable.

  As described above, in the shock absorber D of the present embodiment, the damping force on both the expansion side and the pressure side of the shock absorber D can be made variable using a single electromagnetic relief valve 4, and the solenoid 4c controls not the two damping valves on the expansion side and the pressure side, but a single relief valve, so that the stroke of the solenoid 4c does not become long, and the shock absorber D is made small and light. In addition, the cost can be reduced.

  The direction switching valve 5 can adopt a simple structure as shown in FIGS. 2 and 3, and does not need to be driven by a solenoid that operates using the pressure in the one chamber R1 and the other chamber R2 as pilot pressure. Therefore, the installation of the direction switching valve 5 does not cause an increase in the size of the shock absorber D.

  As described above, the electromagnetic relief valve 4 can exert a damping force on both sides of the pressure expansion of the shock absorber D. However, a separate passage is provided to connect the one chamber R1 and the other chamber R2. Alternatively, a damping valve may be provided in the passage.

  Subsequently, when a higher damping force is desired, the circuit configuration of the above-described shock absorber D is changed as follows, like the shock absorber D1 in the modification of the embodiment shown in FIG. That's fine. In the description of the shock absorber D1 of this modification, since the description of the same members as those of the shock absorber D of the above-described embodiment is repeated, the detailed description is omitted only by attaching the same reference numerals. I decided to.

  Specifically, in the shock absorber D1 in this modified example, in addition to the circuit configuration of the shock absorber D, the fixed throttle 40 provided upstream of the electromagnetic relief valve 4, the upstream of the fixed throttle 40, and the electromagnetic relief valve 4 is connected to the downstream side of the bypass 41, and is energized in the valve opening direction by the pressure upstream of the bypass 41, and is energized in the valve closing direction by the pressure upstream of the electromagnetic relief valve 4. The direction switching valve 5 selectively connects the high pressure side of the one chamber R1 or the other chamber R2 to the upstream side of the fixed throttle 40, and selects the low pressure side of the one chamber R1 or the other chamber R2. Therefore, it is connected downstream of the electromagnetic relief valve 4.

  That is, in this buffer D1, the relief valve 42 is used as a main damping valve, and the electromagnetic relief valve 4 is used for the purpose of controlling the relief pressure of the relief valve 42. Specifically, the pressure upstream of the electromagnetic relief valve 4 is controlled by the electromagnetic relief valve 4, and this upstream pressure is guided to one end of the valve main body 42a of the relief valve 42 through the pilot passage 42b to cause the valve main body 42a to move. Since the valve is biased in the closing direction, the relief pressure of the relief valve 42 can be controlled by controlling the upstream pressure by the electromagnetic relief valve 4.

  The relief valve 42 causes the pressure upstream of the bypass 41 to act on the other end of the valve body 42a through the pilot passage 42c. In addition, a spring 42d is provided at one end of the valve body 42a to bias the valve body 42a in the closing direction. The relief valve 42 is controlled by the pressure upstream of the fixed throttle 40 and the electromagnetic relief valve 4. When the differential pressure between the fixed throttle 40 and the pressure of the electromagnetic relief valve 4 reaches the relief pressure, the valve body 42a is opened against the urging force of the spring 42d to open the bypass 41. Resistance is given to the flow of the working fluid which passes according to the size of pressure.

  On the other hand, since the electromagnetic relief valve 4 is used for the purpose of controlling the pilot pressure of the relief valve 42, the flow rate of the working fluid can be reduced, and the stroke length of the solenoid 4c can be set to the buffer D of the embodiment. The buffer D1 can be further reduced in size and weight, and the cost can be further reduced.

  In addition, the electromagnetic relief valve 4 does not directly control the pressure in the one chamber R1 and the other chamber R2, but the relief valve 42 performs the control, so that the thrust of the solenoid 4c directly controls the pressure in the one chamber R1. There is no need to control the pressure in the other chamber R2, and the differential pressure between the one chamber R1 and the other chamber R2 can be increased without increasing the thrust force of the solenoid 4c. Therefore, the shock absorber D1 without increasing the size of the solenoid 4c. It is possible to increase the generation damping force.

  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.

INDUSTRIAL APPLICABILITY The present invention can be used for a shock absorber that attenuates vibration of a vibration-controlled object, in addition to a vehicle steering damper.

DESCRIPTION OF SYMBOLS 1 Cylinder 1a, 1b Port 2 in cylinder 2 Piston 3 Damping passage 4 Electromagnetic relief valve 4a Valve body 4b Pilot passage 4c Solenoid 5 Directional switching valve 5a Switching valve body 5b in direction switching valve One side communication position 5c in direction switching valve Direction switching valve Pilot passages 6 and 7 at the other side communication positions 5d and 5e in the direction switching valve 8 and lid 8 rod 8a mounting portion 9 accumulators 10 and 20 housings 10a, 10b, 20a and 20b stoppers 11 and 21 spools 12 and 22 upstream ports 13 and 14 23, 24 Downstream ports 15, 16, 29 Through holes 21a, 21b Annular groove 25 High pressure priority valve 26, 27 Spherical body 28 Spring 30 One port 31 Other port 40 Fixed throttle 41 Bypass 42 Relief valve 42a Valve body 42b, 42c Oke Pilot passage 42d spring D, D1 shock absorber R1 one chamber R2 other chamber

Claims (2)

A cylinder,
A piston that is slidably inserted into the cylinder and divides the cylinder into one chamber and the other chamber;
An electromagnetic relief valve that applies a damping force to the working fluid that has flowed out of the one chamber and the other chamber ;
The one chamber with connecting one side connecting positions and the other chamber for connecting the other chamber to the downstream of the electromagnetic relief valve with connecting the one chamber to the upstream of the electromagnetic relief valve upstream of the solenoid relief valve and a directional control valve for chromatic and other side connecting positions to connect to the downstream of the electromagnetic relief valve,
The directional control valve is switched to the one-way chamber and the other chamber the one chamber pressure is above the other chamber the one side connecting positions exceeds the pressure of the pilot pressure the pressure during the movement within the cylinder of the piston fairly, buffer the pressure of the other chamber, characterized in that the Waru switching to the other side connecting positions exceeds the pressure in the one chamber. A fixed throttle provided upstream of the solenoid relief valve, a bypass for connecting the downstream of the fixed throttle upstream and the electromagnetic relief valve, a pressure upstream of the middle provided the bypass of the bypass valve opening direction while being energized and a relief valve which is biased in the valve closing direction by the upstream pressure of the electromagnetic relief valve, the directional control valve is upstream of selectively the fixed stop one chamber or the other chamber the The shock absorber according to claim 1, wherein the shock absorber is connected.

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