SHOCK ABSORBERS

Abstract

A shock absorber (AL) comprising: a cylinder (1L); a piston (2L) axially displaceable within the cylinder (1L) and dividing the interior of the cylinder (1L) into an expansion chamber (La) and a compression chamber (Lb); a piston rod (3L) coupled to the piston (2L) and the end of which projects outwards on one side of the cylinder (1L); a rigid damping element (20) resisting a fluid flow from the expansion chamber (La) to the compression chamber (Lb); an electromagnetic valve (VL) capable of changing the opening area of ​​a bypass channel (3a) to bypass the rigid damping element (20) and connect the expansion pressure chamber (La) and the compression chamber (Lb);and a soft damping element (50) located in the bypass channel (3a) and connected in series with the electromagnetic valve (VL), wherein the hard damping element (20) comprises a passage (20b) and a leaf valve (50a) arranged parallel to the passage, and wherein the soft damping element (50) comprises a large-diameter passage (50b) whose opening area is larger than the opening area of ​​the passage (20b).

Description

TECHNICAL AREA

[0001] The present invention relates to an improvement of a shock absorber. State of the art

[0002] Typically, some shock absorbers contain fluid such as hydraulic oil in a cylinder, provide resistance to a fluid flow when a piston moves through a damping element in a cylinder, and exert a damping force caused by the resistance.

[0003] The damping element comprises, for example, a passage and a leaf valve arranged parallel to the passage. Only when the piston speed is in a low speed range and the differential pressure between the upstream and downstream sides of the damping element is lower than the opening pressure of the leaf valve does the fluid flow through the passage. Conversely, when the piston speed is in a medium to high speed range and the differential pressure is equal to or higher than the opening pressure of the leaf valve, the fluid flows through the leaf valve.

[0004] Therefore, the characteristic curve of the damping force (hereinafter referred to as the "damping force characteristic") with respect to the piston speed of the shock absorber changes from a through-flow characteristic curve, which is proportional to the square of the piston speed specific for the through-flow, to a valve characteristic curve, which is proportional to the piston speed specific for the reed valve when the reed valve is open.

[0005] Additionally, for the purpose of adjusting the generated damping force, some shock absorbers include a bypass channel that bypasses the damping element, a needle valve that regulates the opening area of ​​the bypass channel, and a control valve that controls the back pressure of the leaf valve forming the damping element (for example, in patent specifications 1 and 2). Reference list of patent specifications Patent specification: JP 2010-7758 A Patent specification 2: JP 2014-156885 A Description of the invention: Technical problem

[0006] For example, in the shock absorber that includes a needle valve, described in JP 2010-7758 A, when the needle valve is extended to increase the opening area of ​​the bypass channel, the flow rate of the fluid passing through the damping element decreases to reduce the damping force produced (soft mode in JP 2010-7758 A). Fig. 7) On the other hand, if the opening area of ​​the bypass channel is reduced, the flow rate of the fluid flowing through the damping element increases in order to increase the damping force generated (hard mode in Fig. 7).

[0007] This type of damping force adjustment via the needle valve is primarily used to adjust the damping force at low piston speeds. While adjusting the bypass channel opening area via the needle valve also allows for easy adjustment of the damping force at medium and high piston speeds, increasing the adjustment range becomes more challenging.

[0008] On the other hand, in the case of the shock absorber that includes a control valve, as described in JP 2014-156885A; if the control valve's opening pressure is reduced to decrease the reed valve's back pressure, the reed valve's opening pressure is reduced to decrease the damping force produced (soft mode in Fig.8) On the other hand, if the control valve's opening pressure is increased to increase the reed valve's back pressure, the reed valve's opening pressure also increases to increase the damping force generated (hard mode in Fig. 8).

[0009] As described above, when the back pressure of the leaf valve is controlled to change the valve opening pressure, the adjustable damping force range can be increased when the piston speed is in the mid- to high-speed range. However, in this case, because the characteristic curve indicates the damping force characteristic in the mid- to high-speed range, it shifts up and down without changing its slope. Particularly in the firm setting, the slope of the characteristic curve changes rapidly as it shifts from the low-speed to the mid- to high-speed range. Therefore, when the shock absorber is mounted on a vehicle, there is a possibility that an occupant will experience discomfort and that ride comfort will be reduced.

[0010] Against this background, an objective of the present invention is to solve these problems and to provide a shock absorber that is able to increase the adjustment range of the damping force when the piston speed is in a medium and high speed range, and to improve driving comfort when the shock absorber is mounted on a vehicle. Solution to the problem

[0011] A shock absorber for solving the aforementioned problems, comprising: a hard damping element that exerts resistance to a fluid flow from an expansion chamber to a compression chamber, which are separated by a movable piston inserted into a cylinder; an electromagnetic valve capable of changing the opening area of ​​a bypass channel to bypass the hard damping element and connect the expansion chamber and the compression chamber; a soft damping element located in the bypass channel and connected in series with the electromagnetic valve, wherein the hard damping element comprises a passage and a leaf valve arranged parallel to the passage, and wherein the soft damping element comprises a passage.

[0012] According to the configuration above, the characteristic curve of the damping force generated by the shock absorber becomes a passage-specific characteristic curve when the piston speed is in a low speed range, and becomes a valve-specific characteristic curve for the reed valve when the piston speed is in a medium and high speed range.When the opening area of ​​the bypass channel is changed by the electromagnetic valve, the distribution ratio of a flow passing through the hard damping element and a flow passing through the soft damping element in the fluid moving from the expansion chamber to the compression chamber is changed, so that both a damping coefficient when the piston speed is in the low speed range and a damping coefficient when the piston speed is in the medium and high speed range can be freely adjusted, and the adjustment range of the generated damping force can be increased.

[0013] Furthermore, in a soft mode, where the opening area of ​​the bypass channel is increased, both the damping coefficient at low piston speeds and the damping coefficient at medium and high piston speeds can be reduced. Conversely, in a hard mode, where the opening area of ​​the bypass channel is reduced, both the damping coefficient at low piston speeds and the damping coefficient at medium and high piston speeds can be increased. As a result, when the damping force characteristic transitions from the flow characteristic at low speeds to the valve characteristic at medium and high speeds, the change in the slope of the characteristic curve can be smooth in each mode.Therefore, when the shock absorber according to the present invention is mounted on a vehicle, the driving comfort of the vehicle can be improved.

[0014] Furthermore, the damping element on the soft side of the shock absorber can contain a reed valve arranged parallel to the large-diameter passage. As a result, even when a valve with high stiffness is used as the reed valve of the hard damping element, the damping force in the soft mode is not excessive. Therefore, the adjustable damping force range at medium and high piston speeds can be further increased.

[0015] Furthermore, the electromagnetic valve in the shock absorber can be adjusted so that its opening degree changes proportionally to the excitation level. This allows the opening area of ​​the bypass channel to be continuously adjusted.

[0016] Furthermore, in the shock absorber, the electromagnetic valve can comprise a cylindrical holder with an opening formed therein and connected to the bypass channel, a slide that is movably inserted into the holder and can open and close the opening, a pre-tensioned spring that biases the slide in one direction of movement, and a solenoid that exerts a longitudinal force on the slide opposite to the biased spring. In this way, since the degree of opening of the electromagnetic valve can be easily increased without increasing the stroke of the control piston, which is a valve body of the electromagnetic valve, the adjustable range of the opening area of ​​the bypass channel can be easily increased.Furthermore, the relationship between the degree of opening and the excitation amount of the electromagnetic valve can easily be set to a proportional relationship with a positive proportionality constant or a negative proportional relationship with a negative proportionality constant.

[0017] Furthermore, in the shock absorber, the piston can be connected to the other end of the piston rod, and the shock absorber can include a reservoir connected to the compression chamber and a check valve that only allows fluid flow from the compression chamber to the expansion chamber. In this way, the shock absorber can be a unidirectional shock absorber that generates a damping force only during an expansion stroke. Advantageous effects of the invention

[0018] According to the shock absorber of the present invention, it is possible to increase the adjustment range of the damping force when the piston speed is in the medium and high speed range, and to improve driving comfort when the shock absorber is mounted on the vehicle. List of characters Fig. Figure 1 is a front view schematically showing an installed state of a shock absorber on an expansion side, which is a shock absorber according to an embodiment of the present invention. Fig. Figure 2 is a longitudinal sectional view of the shock absorber on the expansion side, which is the shock absorber according to the embodiment of the present invention. Fig. 3 is a vertical section view showing part of Fig. 2 shows in enlarged form. Fig.Figure 4 is a hydraulic circuit diagram of the shock absorber on the expansion side, that the shock absorber is according to the embodiment of the present invention. Fig. Figure 5 is a hydraulic circuit diagram of a shock absorber on a compression side, which is paired with the shock absorber on the expansion side, such that the shock absorber is according to the embodiment of the present invention. Fig. Figure 6 is a damping force characteristic curve diagram showing a characteristic curve of an expansion-side damping force in relation to a piston speed of the shock absorber on the expansion side, that the shock absorber is according to the embodiment of the present invention. Fig. Figure 7 is a damping force characteristic curve diagram showing a characteristic curve of a damping force as a function of the piston speed of a shock absorber with a conventional needle valve. Fig.Figure 8 is a damping force characteristic curve diagram showing the course of the damping force as a function of the piston speed of a shock absorber with a conventional control valve. Description of the embodiments

[0019] A shock absorber according to one embodiment of the present invention is described below with reference to the drawings. The same reference numerals used in the various figures denote the same or corresponding components. Furthermore, the shock absorber according to one embodiment of the present invention is used for a front fork that suspends a front wheel of a saddle-ridden vehicle. In the following description, the top and bottom surfaces in a state in which the front fork, including the shock absorber, is attached to a vehicle are simply referred to as the "top" and "bottom" surfaces, unless otherwise specified.

[0020] As in Fig. As shown in Figure 1, a front wheel fork F comprises a pair of shock absorbers. AL and AR, axle-side brackets BL and BR, which are the lower end sections of the shock absorbers AL and AR to couple with an axle of a front wheel W, and a pair of upper and lower vehicle body-side mounts CU and CL that hold the upper end sections of the shock absorbers AL and AR couple. The body-side mounts CU and CL are coupled by a steering shaft S.

[0021] The steering shaft S is rotatably mounted in the head tube P of the vehicle body, and a steering wheel H is connected to the upper bracket CU. When the steering wheel H is turned, the entire front fork F rotates around the steering shaft S. At this point, the front wheel W rotates together with the front fork F to change its direction.

[0022] In the present embodiment, one of the two shock absorbers ALand AR a shock absorber AL on an expansion side for generating and adjusting an expansion-side damping force, the shock absorber AL The shock absorber according to the embodiment of the present invention is the first. The other shock absorber is an AR shock absorber on a compression side for generating and adjusting a compression-side damping force. In Fig. 1 is the left side in the drawing of the shock absorbers. AL on the expansion side, and the right side is the AR shock absorber on the compression side, but it goes without saying that these arrangements can also be reversed.

[0023] First, the shock absorber AL on the expansion side, which is the shock absorber according to the embodiment of the present invention, is described in more detail.

[0024] As in Fig. As shown in 2, the shock absorber includes ALOn the expansion side, a telescopic tube element TL is provided, comprising an outer tube 10L and an inner tube 10L, which is slidably inserted into the outer tube 11L. In the present embodiment, the tube element TL is of a reversed type: the outer tube 10L is a body-side tube, and the body-side supports CU and CL are coupled; and the inner tube 11L is an axle-side tube, and the axle-side support BL is coupled.

[0025] Then, when the front wheel W oscillates up and down, as the vehicle of the type ridden in a saddle travels on an uneven road surface or similar, the inner tube 11L moves in and out of the outer tube 10L, and the tube element TL expands and contracts. Such expansion and contraction of the tube element TL is also referred to as the expansion and contraction of the shock absorber. ALThe pipe element TL can be an upright type, the outer pipe 10L an axle-side pipe and the inner pipe 11L a vehicle body-side pipe.

[0026] The upper end of the outer tube 10L, which is the upper end of the tube section TL, is then closed by a cap 12L. On the other side, the lower end of the inner tube 11L, which is the lower end of the tube section TL, is closed by the axial support BL. Furthermore, a cylindrical gap formed between the overlapping section of the outer tube 10L and the inner tube 11L is closed by an annular sealing element 13L, which is attached to the lower end of the outer tube 11L and slidably contacts the outer circumference of the inner tube 10L.

[0027] In this way, the interior of the tube section TL is an enclosed space, and a shock absorber main body DL is housed within the tube section TL. The shock absorber main body DL comprises a cylinder. 1L , which is provided in the inner tube 11L, a piston 2L , sliding into the cylinder 1L is inserted, and a piston rod 3L , whose lower end is connected to the piston 2L is connected and its upper end faces the outside of the cylinder 1L protrudes and is connected to the 12L cap.

[0028] Since the cap (12L) is connected to the outer tube (10L), it can be said that the piston rod 3L is connected to the outer tube 10L. Furthermore, the cylinder 1L connected to the inner tube 11L. In this way, the shock absorber main body DL is inserted between the outer tube 10L and the inner tube 11L.

[0029] A ring-shaped head element 14L is located at the upper end of the cylinder.1L attached, and the piston rod 3L It runs through the interior of the head element 14L, allowing it to move axially. The head element 14L supports the piston rod. 3L sliding off. A support spring 15L, which contains a coil spring, is inserted between the head element 14L and the cap 12L.

[0030] If the shock absorber AL On the expansion side, the piston rod expands and contracts, and the inner tube 11L moves in and out of the outer tube 10L. 3L into the cylinder 1L in and out of this, and the piston 2L moves in the cylinder 1L up and down (in the axial direction). When the shock absorber AL contracted on the expansion side and the piston rod 3L into the cylinder 1L When this occurs, the support spring 15L is compressed and exerts an elastic force to compress the shock absorber. ALto pre-tension on the expansion side in the expansion direction. In this way, the 15L suspension spring exerts an elastic force that corresponds to the compression force in order to elastically support the vehicle body.

[0031] The shock absorber AL On the expansion side of the present embodiment is a single-tube type, and the piston rod 3L extends from one side of the piston 2L to the outside of the cylinder 1L In contrast, the shock absorber AL On the expansion side, it can also be a double-rod type, and the piston rod can extend from both sides of the piston to the outside of the cylinder. Furthermore, the piston rod can 3L downwards out of the cylinder 1L protrude and be connected to the axle side, and the cylinder 1LIt can be connected to the side of the vehicle body. Furthermore, the 15L suspension spring can be a type of spring other than a coil spring, e.g., an air spring.

[0032] Then, in the cylinder 1L a fluid chamber LL is formed, which is filled with a fluid such as hydraulic oil, and the fluid chamber LL is connected to an expansion-side chamber. La and a compression-side chamber Lb through the piston 2L The shock absorber is divided into two chambers. The expansion chamber is the chamber compressed by the piston when the shock absorber expands, located between the two chambers separated by the piston. Conversely, the compression chamber is the chamber compressed by the piston when the shock absorber contracts, located between the two chambers separated by the piston.

[0033] Furthermore, there is a space outside the cylinder. 1LMore precisely, a space between the shock absorber main body DL and the tubular element TL, a fluid storage chamber RL. The fluid storage chamber RL contains the same fluid as the fluid in the cylinder. 1L The liquid is stored and a gas chamber GL, in which gas such as air is enclosed, is formed on top of the liquid level. In this way, the pipe element TL acts as the outer shell of a tank. 16L , which separates the liquid from the liquid in the cylinder 1L saves.

[0034] The liquid storage chamber RL in the tank 16L is connected to the compression-side chamber Lb in connection, and the pressure in the compression-side chamber Lb The pressure (tank pressure) is always essentially the same as the pressure in the tank. 16L (Liquid storage chamber RL). The piston 2Lis provided with an expansion-side channel 2a and a compression-side channel 2b, which are connected to the expansion-side chamber La and the compression-side chamber Lb They are connected, and attached there is a hard damping element. 20 , which corresponds to the fluid flow from the expansion-side chamber L1 to the compression-side chamber Lb in the expansion channel 2a, there is resistance, and a compression-side check valve 21 , which directs the fluid flow from the compression-side chamber Lb to the expansion-side chamber L1 in the compression-side channel 2b.

[0035] The hard damping element 20 includes a leaf valve 20a , which is on the underside of the piston 2L is arranged, and a passage 20b ( Fig. 4), which runs parallel to the leaf valve 20a is intended. With the leaf valve 20aIt is a thin, ring-shaped plate made of metal or similar material, or a laminate in which the ring-shaped plates are stacked, which is elastic and attached to the piston. 2L is installed in such a way that deflection on the outer circumferential side is permissible. The pressure in the expansion chamber La acts in a direction in which the outer circumferential section of the leaf valve 20a is bent downwards. The passage 20b is formed by a groove located in the outer circumferential section of the leaf valve 20a is intended to be located on a valve seat of the piston. 2L sits and is separated from it by a plunger provided in the valve seat, or similar.

[0036] The expansion-side chamber La is by the piston 2L compressed when the shock absorber ALOn the expansion side, it expands, and the internal pressure rises and becomes higher than the pressure in the compression-side chamber. Lb If the piston speed is in a low speed range at the time of shock absorber expansion... AL on the expansion side and a differential pressure between the expansion-side chamber La and the compression-side chamber Lb is lower than the valve opening pressure of the leaf valve 20a , the liquid flows through the passage 20b from the expansion-side chamber La to the compression-side chamber Lb, and resistance is encountered against the fluid flow. Additionally, if the piston speed increases on the expansion side at the time of expansion of the shock absorber Al, and the piston speed is in a medium to high speed range, and the differential pressure increases and is equal to or higher than the valve opening pressure of the reed valve. 20a When this happens, the outer circumferential section of the leaf valve bends. 20a so that the fluid from the expansion-side chamber La to the compression-side chamber Lb through the gap between the outer circumferential section and the piston 2L is shaped, flows, and resistance is encountered against the flow of liquid.

[0037] As described above, the hard damping element 20 , which allows passage 20b and that parallel to the passage 20b arranged leaf valve 20aincludes a first damping element on the expansion side, which restricts the fluid flow from the expansion-side chamber La to the compression-side chamber Lb opposes resistance when the shock absorber AL It expands on the expansion side. The resistance is caused by the hard damping element. 20 On the expansion side, the passage 20b caused when the piston speed is in the low speed range, and through the reed valve 20a , when the piston speed is in the medium and high speed range.

[0038] On the other hand, the compression-side check valve opens 21 the compression-side channel 2b, when the shock absorber AL on the expansion side it contracts, and allows the flow of fluid from the compression-side chamber to pass through. Lb towards the expansion-side chamber Lain the compression-side channel 2b, but keeps the compression-side channel 2b in a closed state when the shock absorber AL It expands on the expansion side. The compression-side check valve 21 The present embodiment uses a leaf valve, but it can also be a disc valve or the like.

[0039] Then the piston rod 3L equipped with a unit for adjusting the damping force to control the flow rate through the hard damping element 20 to change the flowing fluid. The damping force adjustment unit includes an electromagnetic valve. VL , which is capable of increasing the opening area of ​​an expansion-side bypass channel 3a to change the hard damping element 20 deals with and with the expansion-side chamber La and the compression-side chamber Lbis connected, and a soft damping element 50 , which is in series with an electromagnetic valve VR partially in the expansion-side bypass channel 3a is planned.

[0040] More precisely, as in Fig. As shown in 3, the piston rod includes 3L a piston retaining element 30L positioned at one end thereof, a magnet housing element 31L connected to one end thereof, and a cylindrical rod main body 32L connected to one end thereof and extending to the outside of the cylinder 1L The piston retaining element 30L comprises a cylindrical housing section 30a with a base and an axle section 30b, which projects downwards from a base section of the housing section 30a and holds an annular piston. 2L is which is attached to an outer circumference of axle section 30b with a nut NL.

[0041] A valve housing 5L, which divides the interior of the cylindrical part of the housing part 30a into an upper chamber 30c and a lower chamber 30d, is attached to the inner circumference of the cylindrical part of the housing part 30a. A channel 5a is formed in the valve housing 5L, connecting the upper chamber 30c and the lower chamber 30d, with the soft damping element 50 in the channel 5a. Furthermore, an elongated hole 30e is formed in the axial section 30b of the piston retaining element 30L, which opens downwards and is connected to the interior of the housing section 30a, the lower chamber 30d and the compression-side chamber. Lb are connected to each other by the elongated hole 30e.

[0042] The magnet housing element 31L then comprises a cylindrical section 31a, which is screwed to the outer circumference of the upper end of the housing section 30a. A laterally open hole 31b is formed in the cylindrical section 31a, and the lateral expansion chamber La The interior of the magnetic housing element 31L is connected to each other via the lateral hole 31b. The electromagnetic valve VL is partially provided in the channel that connects the lateral hole 31b and the upper chamber 30c.

[0043] In the present embodiment, the expansion-side bypass channel comprises 3a , the lateral opening 31b, the upper chamber 30c, the lower chamber 30d and the elongated hole 30e, which are formed in the magnet housing element 31L or the piston retaining part 30L and the hard damping element 20 bypasses the electromagnetic valve. VL and the soft damping element 50are in the expansion-side bypass channel 3a partially arranged in series. The outer diameters of the magnet housing element 31L and the piston retaining element 30L, which form the electromagnetic valve VL and the soft damping element 50 The volumes are smaller than the inner diameter of the cylinder. 1L , so that the expansion-side chamber La is not subdivided by these elements.

[0044] The soft damping element 50 includes a leaf valve 50a , which is located on the underside of the valve housing 5L, and a passage 50b ( Fig. ), which runs parallel to the leaf valve 50a is planned.

[0045] The leaf valve 50ais a thin, ring-shaped plate made of metal or similar material, or a laminate in which the ring-shaped plates are stacked, is elastic, and is attached to the valve body 5L in a condition in which deflection is possible on the outer circumferential side. The pressure in the upper chamber 30c acts in a direction in which the outer circumferential area of ​​the valve blade deflects. 50a is bent downwards. The passage 50b is formed by a groove located in the outer circumferential area of ​​the leaf valve 50a is provided which sits on a valve seat of the valve housing 5L and is separate from it and a plunger or similar is provided in the valve seat.

[0046] The pressure in the upper chamber 30c is increased by increasing the pressure in the expansion-side chamber. La is recorded when the shock absorber AL on the expansion side, and the electromagnetic valve VLthe expansion-side bypass channel 3a opens. If the piston speed at the time of shock absorber expansion AL on the expansion side in the low speed range and the differential pressure between the upper chamber 30c and the lower chamber 30d is lower than the valve opening pressure of the reed valve 50a , the liquid flows through the passage 50b from the upper chamber 30c to the lower chamber 30d, i.e. from the expansion-side chamber La to the compression-side chamber Lb , and resistance is encountered against the fluid flow. Additionally, when the piston speed increases during the expansion of the shock absorber. AL on the expansion side increases and the piston speed is in the medium and high speed range and the differential pressure increases and is equal to or higher than the valve opening pressure of the reed valve. 50aWhen this happens, the outer circumferential section of the leaf valve bends. 50a , so that the fluid flows through the gap formed between the outer circumferential section and the valve housing 5L from the upper chamber 30c to the lower chamber 30d, i.e. from the expansion-side chamber La to the compression-side chamber Lb flows, and resistance is encountered against the flow of liquid.

[0047] As described above, the soft damping element 50 , which allows passage 50b and that parallel to the passage 50b arranged leaf valve 50a includes a second damping element on the expansion side, which provides resistance to the fluid flow from the expansion-side chamber La to the compression-side chamber Lb through the expansion-side bypass channel 3a opposes when the shock absorber ALIt expands on the expansion side. The resistance is caused by the soft damping element. 50 On the expansion side, the passage 50b caused when the piston speed is in the low speed range, and through the reed valve 50a , when the piston speed is in the medium and high speed range.

[0048] Furthermore, the leaf valve 50a of the soft damping element 50 a valve with lower valve stiffness (more flexible) than the leaf valve 20a of the hard damping element 20 And if the flow rates are the same, the resistance (pressure loss) opposing the flow of the fluid is low. In other words, under the same conditions, the fluid is more likely to pass through the leaf valve. 50a than through the leaf valve 20a flows. Furthermore, the passage 50bof the soft damping element 50 a passage with a large diameter and a larger opening area than the passage 20b of the hard damping element 20 , and if the flow rates are the same, the resistance (pressure loss) to the fluid flow is low.

[0049] The electromagnetic valve then includes VL a cylindrical bracket 6L , which are in the piston rod 3L is attached, a slider 7L , which can be moved back and forth in the holder 6L a preload spring is used 8L , which the slider 7L in one direction of movement, and a solenoid 9L , which provides a thrust in the opposite direction to a preload force of the preload spring 8L on the slider 7L exerts its influence. The degree of opening of the electromagnetic valve is then determined. VL by changing the position of the slider7L in holder 6L set.

[0050] More precisely, the holder 6L along the central axis of the piston rod 3L above the valve housing 5L in the piston rod 3L arranged in a state in which one end is axially oriented towards the upper side (side of the magnet housing element 31L) and the other end towards the lower side (side of the valve housing 5L). Furthermore, one or more radially penetrating openings are 6a in the holder 6L trained. The openings 6a stand above the lateral hole 31b of the magnet housing element 31L with the expansion-side chamber La in connection and are controlled by the slider 7L open and closed.

[0051] The slider 7L It has a cylindrical shape and slides into the holder. 6L A 70L plate is inserted. It is placed on the upper end of the slide.7L attached, and a piston 9a (described later) of the solenoid 9L It rests against plate 70L. On the other side, the preload spring is positioned. 8L to the lower end of the slider 7L to turn the slider 7L to pre-tension in an upward thrust direction.

[0052] One in the middle of the slider 7L The central hole 7a opens downwards and is connected to the upper chamber 30c. Furthermore, the slide... 7L An annular groove 7b is formed along the circumferential direction of the outer circumference, and one or more side holes 7c are formed which connect the interior of the annular groove 7b to the central hole 7a. As a result, the interior of the annular groove 7b is in communication with the upper chamber 30c via the side holes 7c and the central hole 7a.

[0053] According to the above configuration, when the slider 7Lis in a position where the annular groove 7b is aligned with the openings 6a the holder 6L Facing the expansion side, there is a connection between the expansion-side chamber La and the upper chamber 30c is permitted. The condition in which the annular groove 7b and the openings 6a "are facing each other" here refers to a state in which the annular groove 7b and the openings 6a overlap each other in a radial direction and the opening area of ​​the expansion-side bypass channel 3a changes according to the overlap amount.

[0054] For example, if the overlap amount between the annular groove 7b and the openings 6a increases and the opening degree of the electromagnetic valve VL As the pressure increases, the opening area of ​​the expansion-side bypass channel also increases. 3a. On the other hand, if the overlap amount between the annular groove 7b and the openings 6a decreases and the opening degree of the electromagnetic valve VL As the area decreases, the opening area of ​​the expansion-side bypass channel decreases. 3a off. If the slider 7L moved into a position in which the annular groove 7b and the connections 6a do not completely overlap and the electromagnetic valve VL When closed, the connection of the expansion-side bypass channel is 3a interrupted.

[0055] Although not shown in detail, the solenoid 9L of the electromagnetic valve VLThe solenoid is housed in the magnet housing element 31L and comprises a cylindrical stator with a coil, a cylindrical movable iron core movably inserted into the stator, and a piston 9a attached to the inner circumference of the movable iron core and having a tip that rests against the plate 70L. A wiring harness 90L connects the solenoid. 9L Powered by electricity, it protrudes outwards through the inside of the main body of the 32L rod and is connected to a power supply.

[0056] If the solenoid 9L When the cable harness 90L is excited, the movable iron core is pulled downwards, the piston 9a moves downwards, and the slide 7L is opposed to the preload force of the preload spring 8L pressed downwards. Then the ring-shaped groove 7b and the openings align. 6a opposite, and the electromagnetic valve VLis opened. The relationship between the degree of opening of the electromagnetic valve VL and the excitation amount of the solenoid 9L This is a proportional relationship with a positive proportionality constant, and the degree of opening increases as the excitation level increases. Furthermore, when the excitation of the solenoid... 9L If the electromagnetic valve is interrupted, it will be activated. VL closed.

[0057] As described above, the electromagnetic valve VL In the present embodiment, a normally closed type, which includes the slider. 7L , which is one of the valve bodies, through the preload spring 8L pre-tensions in the closing direction and the slider 7L through the electromagnet 9L in the opening direction. Furthermore, the degree of opening is proportional to the excitation level of the electromagnetic valve. VLto, and the opening area of ​​the expansion-side bypass channel 3a The opening area increases with the degree of opening. Therefore, one can say that the opening area of ​​the expansion-side bypass channel... 3a in relation to the excitation level of the electromagnetic valve VL increases.

[0058] In summary, as in Fig. As shown in 4, the shock absorber includes AL on the expansion side the cylinder 1L , the piston 2L , sliding into the cylinder 1L is used to enclose the inside of the cylinder 1L into the expansion-side chamber La and the compression-side chamber Lb to divide the piston rod 3L , whose tip is connected to the piston 2L is coupled and its end faces the outside of the cylinder 1L protrudes, and the tank 16L , which is connected to the compression-side chamber Lb in the cylinder 1Lis connected, with the pressure in the compression-side chamber Lb The tank pressure is...

[0059] Furthermore, the shock absorber AL provided on the expansion side with the expansion-side channel 2a, the compression-side channel 2b and the expansion-side bypass channel 3a as channels for the connection between the expansion-side chamber La and the compression-side chamber Lb The compression-side channel 2b is equipped with the compression-side check valve. 21 , which only allows a unidirectional flow of fluid from the compression-side chamber Lb to the expansion-side chamber La allows, and the fluid from the expansion-side chamber La to the compression-side chamber Lb through the expansion-side channel 2a or the expansion-side bypass channel 3a flows.

[0060] The expansion-side channel 2a is equipped with the hard damping element. 20 on the expansion side, which allows passage 20b and the one parallel to the passage 20b arranged leaf valve 20a encompasses and opposes the fluid flow. On the other hand, the expansion-side bypass channel 3a with the soft damping element 50 on the expansion side, which allows passage 50b with a larger opening area than that of the passage 20b and the leaf valve 50a with a lower valve stiffness than that of the reed valve 20a includes and parallel to the passage 50b is arranged in such a way that the resistance to the flow of liquid is reduced.

[0061] Furthermore, the expansion-side bypass channel 3a with the electromagnetic valve VL in series with the soft damping element 50on the expansion side, and the opening area of ​​the expansion-side bypass channel 3a can be achieved by adjusting the excitation level for the electromagnetic valve VL to be changed. The electromagnetic valve VL is a normally closed type and is adjusted to fit the opening area of ​​the expansion-side bypass channel. 3a increased in relation to the amount of excitation.

[0062] Next, the AR shock absorber on the compression side, which is connected to the shock absorber, will be described. AL on the expansion side, which is the shock absorber according to the embodiment of the present invention. In the present embodiment, since the basic configurations of the shock absorbers AL Since AR and the specific structure of the shock absorber AR are the same, the description of the specific structure on the compression side is omitted.

[0063] As in Fig.As shown in Figure 5, the shock absorber AR on the compression side comprises a cylinder 1R, a piston 2R which is slidably inserted into the cylinder 1R to divide the interior of the cylinder 1R into an expansion-side chamber Lc and a compression-side chamber Ld, a piston rod 3R whose tip is coupled to the piston 2R and whose end protrudes to the outside of the cylinder 1R, and a tank 16R which is connected to the expansion-side chamber Lc in the cylinder 1R, wherein the pressure in the expansion-side chamber Lc is the tank pressure.

[0064] Furthermore, the shock absorber AR is provided on the compression side with an expansion-side channel 2c, a compression-side channel 2d, and a compression-side bypass channel 3b as channels for the connection between the expansion-side chamber Lc and the compression-side chamber Ld. The expansion-side channel 2c is equipped with an expansion-side check valve 22, which allows only unidirectional fluid flow from the expansion-side chamber Lc to the compression-side chamber Ld; the fluid from the compression-side chamber Ld to the expansion-side chamber Lc flows through the compression-side channel 2d or the compression-side bypass channel 3b.

[0065] The compression-side channel 2d is provided with a hard damping element 23 on the compression side, comprising a passage 23b and a leaf valve 23a arranged parallel to the passage 23b, and resisting the fluid flow. On the other hand, the compression-side bypass channel 3b is provided with a soft damping element 51 on the compression side, comprising a channel 51b with a larger diameter than that of the passage 23b and a leaf valve 51a with a lower valve stiffness than that of the leaf valve 23a, arranged parallel to the passage 51b, thereby reducing the resistance to the fluid flow.

[0066] Furthermore, the compression-side bypass channel 3b is equipped with the electromagnetic valve VR in series with the soft damping element 51, and the opening area of ​​the compression-side bypass channel 3b can be changed by adjusting the excitation quantity for the electromagnetic valve VR. Similar to the electromagnetic valve VL of the shock absorber AL On the expansion side, the electromagnetic valve VR is also of the normally closed type and is adjusted to increase the opening area of ​​the compression-side bypass channel 3b in relation to the excitation amount.

[0067] The shock absorber AR on the compression side is provided with an intake channel 4a that connects the compression-side chamber Ld and the tank 16R, and the intake channel 4a is provided with an intake valve 40 that allows only a unidirectional flow of fluid from the tank 16R to the compression-side chamber Ld.

[0068] The following describes the function of the front fork F with the shock absorber. AL described on the expansion side, which is the shock absorber according to the present invention, and the shock absorber AR paired therewith on the compression side.

[0069] If the shock absorbers AL and AR expand, the piston rods retract. 3L and 3R from the cylinders 1L and 1R back, and the pistons 2L and 2R press the expansion-side chambers La and Lc together. At this point, the shock absorber is moving. AL on the expansion side, the liquid in the expansion-side chamber La through the expansion-side channel 2a or the expansion-side bypass channel 3a into the expansion-side chamber Lb The resistance is provided by the hard damping element. 20 or the soft damping element 50on the expansion side, a force is exerted on the fluid flow, and an expansion-side damping force is generated due to the resistance.

[0070] On the other hand, when the shock absorber AR expands on the compression side, the expansion-side check valve 22 opens, and the fluid in the expansion-side chamber Lc flows through the expansion-side channel 2c into the compression-side chamber Ld. At this point, the fluid can flow through the expansion-side check valve 22 with relatively little resistance. Furthermore, the expansion-side chamber Lc is connected to the reservoir 16R and is held at the reservoir's pressure. Therefore, the expansion-side damping force of the front fork F as a whole is mainly caused by the expansion-side damping force exerted by the shock absorber. AL generated on the expansion side.

[0071] Furthermore, the distribution ratio of the fluid passing through the hard damping element changes. 20 on the expansion side and the fluid that passes through the soft damping element 50 on the expansion side flows when the shock absorber AL on the expansion side, it expands according to the opening area of ​​the expansion-side bypass channel. 3a , thereby increasing or decreasing the damping coefficient to adjust the generated expansion-side damping force.

[0072] In particular, as described above, the hard damping element includes 20 and the soft damping element 50 on the expansion side, the passages 20b and 50b and those running parallel to the passages 20b and 50b arranged leaf valves 20a and 50aTherefore, the damping force characteristic on the expansion side becomes a passage characteristic that is proportional to the square of the piston speed specific to the passage when the piston speed is in the low speed range, and a valve characteristic that is proportional to the piston speed specific to the reed valve when the piston speed is in the medium and high speed range.

[0073] When the excitation amount is sent to the electromagnetic valve VL To increase the degree of opening, the flow rate of the bypass channel is increased. 3a on the expansion side increased to improve the ratio of fluid passing through the hard damping element 20 to reduce the flow on the expansion side and the ratio of fluid passing through the soft damping element. 50 on the expansion side, to increase. Since it is during the passage 50bof the soft damping element 50 it is a passage with a large diameter, whose opening area is larger than that of the passage. 20b of the hard damping element 20 , the damping coefficient decreases in the low, medium and high speed ranges when the ratio of fluid to soft damping element changes 50 The expansion-side damping force, generated in relation to the piston speed, increases, and decreases. When the amount of current supplied to the electromagnetic valve... VL As the amount supplied is maximized, the damping coefficient is minimized and the generated expansion-side damping force is minimized in relation to the piston speed.

[0074] The opposite is true if the excitation level for the electromagnetic valve VL To reduce the degree of opening, the flow rate of the expansion-side bypass is reduced. 3areduced to decrease the ratio of fluid passing through the hard damping element 20 on the expansion side, to increase and the ratio of fluid flowing through the soft damping element 50 on the expansion side, to decrease. Subsequently, the damping coefficient increases in the low, medium, and high speed ranges, and the expansion-side damping force increases in proportion to the piston speed. When the power supply to the electromagnetic valve VL switched off and the electromagnetic valve VL When the expansion-side bypass channel is closed, the connection will be closed. 3a interrupted, so that the entire flow passes through the hard damping element. 20 The fluid flows on the expansion side. Afterwards, the damping coefficient is maximized and the expansion-side damping force is maximized as a function of the piston speed.

[0075] As previously described, if the distribution ratio of the liquid passing through the hard damping element 20 and the liquid that passes through the soft damping element 50 , which are the first and second damping elements on the expansion side, flows through the electromagnetic valve VL When the damping coefficient is changed, it increases or decreases, and the slope of the characteristic curves, which show the damping force characteristics on the expansion side, changes as shown in Fig. 6 shown. The expansion-side damping force is then differentiated between a hard mode, in which the damping force is generated by maximizing the slope of the characteristic curve, and a soft mode, in which the damping force is reduced by minimizing the slope.

[0076] In soft mode, the slope of the characteristic curve representing the damping force characteristic decreases in the low, medium, and high speed ranges, while in hard mode, the slope of the characteristic curve representing the damping force characteristic increases in the low, medium, and high speed ranges. Therefore, the change when the damping force characteristic changes from the flow characteristic to the valve characteristic is gradual in both modes.

[0077] Furthermore, the soft damping element contains 50 the leaf valve 50a with low valve stiffness parallel to the passage 50b Therefore, even if a valve with high valve stiffness and high valve opening pressure is used as a reed valve 20a of the hard damping element 20When used and the adjustment range is increased in the direction of increasing the expansion-side damping force, the damping force in soft mode will not be too large.

[0078] Furthermore, if the shock absorber AL On the expansion side, the liquid expands to the volume of the cylinder. 1L retracted piston rod 3L corresponds to, from the tank 16L into the compression-side space Lb directed. On the other hand, when the shock absorber AR expands on the compression side, the suction valve 40 is opened, and the fluid corresponding to the volume of the piston rod 3R, which was retracted from the cylinder 1R, is supplied from the tank 16R through the intake channel 4a into the chamber Ld on the compression side.

[0079] On the other hand, if the shock absorbers AL and AR contract, the piston rods move 3L and 3R into the cylinders 1Land 1R, and the pistons 2L and 2R compress the compression-side chambers Lb and Ld. At this point, in the shock absorber AR, on the compression side, the fluid in the compression-side chamber Ld moves through the compression-side channel 2d or the compression-side bypass channel 3b into the expansion-side chamber Lc. Resistance to the fluid flow is exerted by the hard damping element 23 on the compression side or the soft damping element 51 on the compression side, and a compression-side damping force caused by the resistance is generated.

[0080] On the other hand, if the shock absorber AL When the expansion side contracts, the compression-side check valve closes. 21 opened, and the fluid in the compression-side chamber Lb flows through the compression-side channel 2b into the expansion-side chamber LaAt this point, the fluid can pass through the compression-side check valve. 21 pass through relatively without resistance. Furthermore, the compression-side chamber is Lb with the tank 16L in connection and is maintained at tank pressure. Therefore, the compression-side damping force of the front fork F as a whole is mainly caused by the compression-side damping force generated by the shock absorber AR on the compression side.

[0081] Furthermore, when the shock absorber AR contracts on the compression side, the distribution ratio of the fluid flowing through the compression-side hard damping element 23 and the fluid flowing through the compression-side soft damping element 51 changes according to the opening area of ​​the compression-side bypass channel 3b, thereby increasing or decreasing the damping coefficient to match the generated compression-side damping force.

[0082] Similar to the hard damping element 20 and the soft damping element 50 On the expansion side, the hard damping element 23 and the soft damping element 51 comprise the passages 23b and 51b and the leaf valves 23a and 51a, which are arranged parallel to the passages 23b and 51b respectively, and the passage 51b of the soft damping element 51 is a large diameter passage whose opening area is larger than that of the passage 23b of the hard damping element 23.

[0083] Therefore, during contraction in soft mode, the slope of the characteristic curve representing the damping force decreases in the low, medium, and high speed ranges, while in hard mode, the slope of the characteristic curve representing the damping force increases in the low, medium, and high speed ranges. Consequently, the change in the damping force characteristic from the flow characteristic to the valve characteristic can occur smoothly in either mode during contraction.

[0084] When the shock absorber AR contracts on the compression side, the fluid corresponding to the volume of the piston rod 3R, which has entered the cylinder 1R, is drained from the expansion-side chamber Lc into the reservoir 16R. On the other hand, when the shock absorber AL When the expansion side contracts, the fluid, which corresponds to the volume of the piston rod, is forced out.3L corresponds to the cylinder 1L ran out of the chamber Lb on the pressure side into the tank 16L guided.

[0085] The following describes the functions and effects of the shock absorber. AL on the expansion side, which is the shock absorber according to the present invention, and the front wheel fork F with the shock absorber AL described on the expansion side and the compression side shock absorber AR.

[0086] The shock absorber AL on the expansion side (shock absorber) according to the present embodiment, the cylinder comprises 1L , the piston 2L , which goes into the cylinder 1L is inserted in an axially movable direction and the interior of the cylinder 1L into the expansion-side chamber La and the compression-side chamber Lb subdivided, and the piston rod 3L , which is connected to the piston 2Lis coupled and has one end coming out of the cylinder 1L stands out.

[0087] Furthermore, the shock absorber includes AL on the expansion side the hard damping element 20 , which is the fluid flow from the expansion-side chamber La to the compression-side chamber Lb opposes the electromagnetic valve VL , which is the opening area of ​​the expansion-side bypass channel (bypass channel) 3a can change the hard damping element 20 bypasses and the expansion-side chamber La and the compression-side chamber Lb connects them, and the soft damping element 50 , which is in series with the electromagnetic valve VL in the expansion-side bypass channel 3a is provided. The hard damping element 20 includes the passage 20b and that parallel to the passage 20barranged leaf valve 20a On the other hand, the soft damping element includes 50 the passage (large diameter passage) 50b, whose opening area is larger than that of the passage 20b .

[0088] According to the configuration above, the damping force characteristic is generated when the shock absorber... AL On the expansion side, the flow characteristic curve specific to the passage when the piston speed is in the low speed range, and the valve characteristic curve specific to the reed valve when the piston speed is in the medium and high speed range. When the opening area of ​​the expansion-side bypass channel 3a through the electromagnetic valve VL When the flow is changed, the distribution ratio of the flow passing through the hard damping element changes. 20 and the flow that passes through the soft damping element 50in the liquid that flows from the expansion-side chamber La to the compression-side chamber Lb moves when the shock absorber AL on the expansion side, so that both the damping coefficient when the piston speed is in the low speed range and the damping coefficient when the piston speed is in the medium and high speed range can be freely adjusted, and the adjustment range of the compression-side damping force can be increased when the piston speed is in the medium and high speed range.

[0089] Furthermore, in soft mode, in which the opening area of ​​the expansion-side bypass channel is 3aWhen the area is increased, both the damping coefficient at low piston speeds and the damping coefficient at medium and high piston speeds are reduced. Conversely, in hard mode, where the opening area of ​​the expansion-side bypass channel is increased, the damping coefficient decreases. 3a While the damping coefficient is reduced, both the damping coefficient at low speeds and the damping coefficient at medium and high speeds are increased. Therefore, when the characteristic curve of the expansion-side damping force changes from the flow characteristic at low speeds to the valve characteristic at medium and high speeds, the change in the slope of the characteristic curve is smooth in each mode.

[0090] In the shock absorber ALOn the expansion side, according to the present embodiment, the soft damping element comprises 50 the passage (large diameter passage) 50b and the leaf valve 50a , which runs parallel to the passage 50b is intended. As previously described, the damping force in soft mode will not be excessively high when the leaf valve is 50a also in the soft damping element 50 is intended, even if the leaf valve 20a of the hard damping element 20 It is a valve with high valve stiffness and high valve opening pressure. That is, according to the configuration above, a valve with high valve stiffness is a reed valve. 20a of the hard damping element 20can be used. In this case, the adjustment range of the damping force is increased in the direction of increasing the expansion-side damping force, so that the adjustment range of the compression-side damping force can be further increased when the piston speed is in the medium and high speed range.

[0091] In the shock absorber AL On the expansion side of the present embodiment, the piston 2L with the other end of the piston rod 3L connected to form a single-rod type. Furthermore, the shock absorber includes AL on the expansion side, the tank 16L , which is connected to the compression-side chamber Lb is connected, and the compression-side check valve (non-return valve) 21 , which only controls the flow of fluid from the compression-side chamber Lb to the expansion-side chamber Laallows this configuration. 3L , which are located in the cylinder 1L moved in and out of it, through the tank 16L can be balanced. In addition, the shock absorber can AL On the expansion side, it should be a unidirectional shock absorber that only exerts a damping force during an expansion stroke.

[0092] The front fork F contains the shock absorber AR on the compression side, which is connected to the shock absorber. ALThe shock absorber AR on the expansion side is paired. The shock absorber AR on the compression side is a unidirectional shock absorber that exerts a damping force only during a contraction stroke. The distribution ratio of the flow passing through the hard damping element 23 on the compression side and the flow passing through the soft damping element 51 on the compression side in the fluid moving from the compression-side chamber Ld to the expansion-side chamber Lc can be changed in accordance with the opening degree of the electromagnetic valve VR to adjust the generated compression-side damping force. Furthermore, the hard damping element 23 on the compression side and the soft damping element 51 on the compression side comprise the passages 23b and 51b and the blade valves 23a and 51a arranged parallel to the passages 23b and 51b, respectively.

[0093] Therefore, with the F-type front fork, the damping force adjustment ranges can be increased on both the expansion and compression sides when the piston speed is in the mid- to high-speed range. Furthermore, with the F-type front fork, when the damping force characteristic changes from the low-speed through-curve to the mid- to high-speed valve-curve, the change in the slope of the characteristic curve can be smooth in every mode, both on the expansion and compression sides. For this reason, when the F-type front fork is installed on the vehicle, the discomfort caused by changes in the slope can be further reduced, and the vehicle's ride comfort can be further improved.

[0094] The electromagnetic valves VL and VR of the shock absorbers ALThe AR of the present embodiment are set such that the degree of opening changes proportionally to the excitation level. According to this configuration, the opening areas of the expansion-side bypass channel can be adjusted. 3a and the compression-side bypass channel 3b can be continuously adjusted.

[0095] Furthermore, the shock absorber includes AL on the expansion side of the present embodiment, the electromagnetic valve VL the cylindrical holder 6L , in which the openings 6a are trained and the one with the expansion-side bypass channel 3a connected to the cylindrical slide 7L , which can be moved back and forth in the holder 6L is installed and the openings 6a can open and close, the preload spring 8L , which the slider 7L in the direction of movement of the slider 7L to one side is biased, and the solenoid9L , which creates a thrust in the opposite direction to the preload force of the preload spring 8L on the slider 7L exercises.

[0096] Here, for example, as in the electromagnetic valve described in JP 2010-7758 A, in a case where a needle valve that can move back and forth is provided as the valve body and the degree of opening is changed by increasing or decreasing a gap formed between a tip end of the needle valve and a valve seat, it is necessary to increase a stroke amount of the valve body in order to increase an adjustment range of the degree of opening, which, however, may not be possible.

[0097] In particular, increasing the stroke of the needle valve increases its moving volume, making it difficult to ensure sufficient clearance. Furthermore, increasing the stroke of a solenoid plunger to increase the needle valve stroke necessitates a design change to the solenoid, which is complex. Additionally, increasing the needle valve stroke without modifying the solenoid design requires a component to increase the needle valve's movement relative to the plunger's movement, increasing the number of components and further complicating the design.

[0098] On the other hand, the electromagnetic valve VL of the present embodiment, which is in the holder 6L trained openings 6a through the cylindrical holder 6Lsliding slider that can be moved back and forth 7L opened and closed, thereby opening the electromagnetic valve VL It opens and closes. Therefore, the degree of opening of the electromagnetic valve can be determined. VL by forming a large number of openings 6a in the circumferential direction of the holder 6L or by forming the openings 6a in a circumferentially extended form, without increasing the stroke of the slide 7L to increase the valve body of the electromagnetic valve VL Therefore, the adjustment range of the opening degree of the electromagnetic valve can be VL can be enlarged, and the adjustment range of the expansion-side damping force can be easily increased.

[0099] Furthermore, according to the configuration above, the relationship between the degree of opening and the excitation amount of the electromagnetic valve can be determined. VLcan be easily modified. For example, in a case where the relationship between the opening degree and the excitation amount of the electromagnetic valve is VL is set to a negative proportional relationship with a negative proportionality constant and it is desired to decrease the degree of opening as the excitation level increases, the openings 6a or the ring-shaped groove 7b for opening the openings 6a be arranged in a position where the openings 6a are maximally open at the time of non-excitation.

[0100] In this way, the relationship between the degree of opening and the excitation amount of the electromagnetic valve can be determined. VLcan be freely modified. Furthermore, the above configuration can be applied to the electromagnetic valve VR of the shock absorber AR on the compression side, and it goes without saying that the ratio between the opening degree and the excitation amount of the electromagnetic valve VR can be changed accordingly. Moreover, the method for adjusting the compression-side damping force in the shock absorber AR on the compression side can have a completely different design than that of the shock absorber itself. AL on the expansion side, and the configuration of the AR shock absorber on the compression side can be freely changed.

[0101] Although the preferred embodiment of the present invention has been described in detail above, modifications, variations, and changes are possible without altering the scope of the claims. The present application claims priority based on patent application No. 2019-038129, filed with the Japanese Patent Office on March 4, 2019, the entire contents of which are incorporated herein by reference. Reference symbol list AL shock absorbers The expansion chamber Lb compression chamber VL Electromagnetic Valve 1L cylinder 2L piston 3L piston rod 3a Expansion side bypass channel (bypass channel) 6L bracket 6a Opening 7L slider 8L Pre-tensioned spring 9L Solenoid 16L tank 20 Hard damping element 20a Leaf valve 20b Passage 21 Compression-side check valve (non-return valve) 50 Soft damping element 50a leaf valve 50b Passage (Large Diameter Passage) QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2010007758 A [0005, 0096] JP 2014156885 A [0005, 0008] JP 20107758 A

[0006] JP 2019038129

[0101]

Claims

[1] A shock absorber comprising: a cylinder; a piston that is axially displaceable within the cylinder and divides the interior of the cylinder into an expansion chamber and a compression chamber; a piston rod that is coupled to the piston and whose end protrudes outwards on one side of the cylinder; a hard damping element that exerts resistance against a fluid flow from the expansion chamber to the compression chamber; an electromagnetic valve capable of changing the opening area of ​​a bypass channel to bypass the hard damping element and connect the expansion pressure chamber and the compression chamber; and a soft damping element located in the bypass channel and connected in series with the electromagnetic valve, wherein the hard damping element comprises a passage and a leaf valve arranged parallel to the passage and wherein the soft damping element comprises a passage with a large diameter, the opening area of ​​which is larger than the opening area of ​​the passage. [2] Shock absorber according to claim 1, wherein the soft damping element comprises a leaf valve that is provided parallel to the large diameter passage. [3] Shock absorber according to claim 1, wherein the degree of opening of the electromagnetic valve changes proportionally to an excitation amount. [4] A shock absorber according to any one of claims 1 to 3, wherein the electromagnetic valve comprises a cylindrical holder with an opening formed therein and connected to the bypass channel, a slide which is inserted into the holder so as to be movable back and forth and which can open and close the opening, a pre-tensioned spring which pre-tensions the slide in a direction of movement of the slide, and a solenoid which exerts a longitudinal force on the slide opposite to the pre-tensioned spring. [5] A shock absorber according to any one of claims 1 to 3, further comprising: a tank connected to an expansion-side chamber; and a check valve that only allows fluid to flow from the compression chamber towards the expansion chamber, with the piston connected to the other end of the piston rod.

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