RU2500936C1 - Adaptive shock absorber - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: shock absorber includes an external tube-reservoir and a working cylinder, which form an annular cavity. A solid piston with a stock is arranged inside the working cylinder in a movable manner. There are through working openings in upper and lower parts of shock absorber walls. Bypass valves are installed at the bottom and the stock guide. There is a restricted closed cavity in the annular cavity, which attaches upper and lower working openings to the inlet cavity of the adjustable electromagnetic valve. A bypass valve is installed on the lower working opening. The valve gate is movably located on outer surface of the guide sleeve by means of a spring. A control gate pressed to the pusher with the spring is movably fixed on the inner surface of the guide sleeve. There are through segmented tangential slots made on side cylindrical surfaces of the guide sleeve, valve and control gates.

EFFECT: improving reliability and simplifying the design of shock absorber.

2 cl, 13 dwg

Description

The invention relates to mechanical engineering, in particular to hydraulic shock absorbers of vehicles and can be used in vehicle suspensions.

Known hydraulic shock absorber of the vehicle suspension [A.I. Kuzmenko, G.M. Yaroslavtsev. Hydraulic shock absorber for vehicle suspension. USSR copyright certificate No. 1157292, cl. F16F 5/00 // B60C 17/04, 04/27/1983], comprising a housing with forward and reverse working chambers connected through a valve system, a compensation chamber and a rod mounted on a shock absorber element connected to the unsprung part of the vehicle made with an axial channel and radial windows overlapped by a spool in the form of a spring-loaded mass, the inlet opening in the channel connecting the forward-flow chamber with the spool device located on the inner working surface of the housing, and the output from the spool device va connected channel with reverse camera.

The presence of a compression valve on the piston determines the possibility of breakdown of the shock absorber at the end of the forward stroke. And the presence of a spool device with an inertial mass makes it possible to breakdown the shock absorber at the end of the return stroke when driving along the "high-frequency profile", since in this mode the inertial mass constantly moves, periodically opening the channel between the forward and reverse cameras. Breakdown of the shock absorber, as a rule, leads to a quick failure of the shock absorber, dramatically reducing its reliability and durability.

Known adjustable shock absorber [Adjustable shock absorber. Self-study program 406. Adaptive control system for the DCC chassis. Design and principle of operation, http://volkswagen.msk.ru, prototype], comprising a piston rod guide on which (outer) tube-reservoir, an intermediate cylinder and a working (inner) cylinder are successively fixed. A piston is moved inside the working cylinder, in which the piston valves are placed, and a compression valve is placed at the base of the working cylinder. The piston is mounted on a rod moving along the guide. A closed annular cylindrical channel formed by the working and intermediate cylinders, the base and the rod guide is connected on one side with a bypass hole to the working chamber 1 formed by the working cylinder, and on the other hand, with the inlet of the adjustable valve. The output channel of the adjustable valve is connected to the working chamber 2 of the shock absorber, formed by a tube - a reservoir, an intermediate cylinder and a rod guide. The adjustable valve is made according to the scheme of an indirect hydraulic valve with electromagnetic control. The governing body of the valve, and therefore the shock absorber as a whole, is an electromagnet that fixes the position of the armature associated with the pusher head. Depending on the magnitude of the current supplied to the coil of the electromagnet, a certain position of the pusher head is established, and therefore the passage area between the pusher head and the control plate in the valve control circuit, and at the same time, the degree of damping of the shock absorber.

The disadvantages of the prototype include the fact that due to the peculiarities of its design and organization of the working process during the operation of the shock absorber, it can be “broken” both in the compression phase and in the rebound phase, which inevitably leads to breakdown of the shock absorber and its subsequent failure. This circumstance sharply reduces the reliability of the shock absorber as a whole. The disadvantages of the prototype should also include some design complexity caused by the introduction of a special Fail Safe valve into the adjustable valve circuit for the implementation of the “Fail Safe” mode, as well as the impossibility of implementing the “blocking mode” shock absorber in this design, in which the entire shock absorber turns into a single rigid link . This mode is necessary to stabilize the movement of the vehicle.

The invention is based on a technical problem, which consists in simplifying the design, increasing the reliability and service life of the shock absorber by eliminating the possibility of breakdown of the shock absorber during its operation, and the implementation of the “blocking mode”.

This problem is solved by the fact that in the shock absorber containing the outer tube-reservoir fixed in the rod guide with an annular cavity formed by the rod fixed in the rod guide, concentrically to the reservoir tube, a working cylinder inside which a monolithic piston with a rod moved in the guide is movably placed, and in the walls of which, in its upper and lower parts, through, respectively, upper and lower working windows are made, and bypass valves are installed in the base and guide, as well as containing bl to the control and a differential-type adjustable electromagnetic valve installed in the tank tube, which includes a sequentially placed control electromagnet, functionally connected to the control unit and consisting of interconnected coils and anchors with a pusher, an inlet cavity, and a concentric valve flap located in it, a guide sleeve , the control valve according to the invention in the annular cavity by means of a closed element, a limited closed cavity connecting the upper e and lower working windows with an inlet cavity of the adjustable solenoid valve, a bypass valve is installed on the lower working window, the valve flap is movably located on the outer surface of the guide sleeve, on the inner cylindrical surface of which the control flap is fixed, movable by a spring, the valve flap is fixed on the guide sleeve using a spring, on the lateral cylindrical surfaces of the guide sleeve, valve flap and control valve through segmented tangential grooves, a limited closed cavity is communicated through a pipeline with an inlet cavity of an adjustable electromagnetic valve, and an annular cavity of a shock absorber is communicated through a pipeline with an outlet cavity of an adjustable electromagnetic valve.

The invention is illustrated by drawings, where: in Fig.1 shows a diagram of a shock absorber in the end phase; figure 2 - some options for the possible implementation of the form of the working windows (view. A); figure 3 is a variant of a possible implementation of the cross-sectional shape of the working window; figure 4 is a diagram of an adjustable solenoid valve operating in a throttle mode; figure 5 is a qualitative picture of the dependence of the cross-sectional area F of the working window on the height h of the lumen of the working window when the piston overlaps the working window when the piston approaches the boundary of the working area; figure 6 - diagram of the shock absorber in the compression phase; 7 is a diagram of a shock absorber at the initial moment of the compression phase; in Fig.8 is a diagram of an adjustable solenoid valve operating on a throttle valve mode; Fig.9 is a diagram of an adjustable solenoid valve operating on a throttle valve mode, with the maximum implementation of the valve mode; figure 10 - operating characteristic of the shock absorber in various adjustment modes; figure 11 is a diagram of an adjustable solenoid valve operating on a throttle valve mode with an average, intermediate control action; in Fig.12 is a diagram of an adjustable solenoid valve in blocking mode; in Fig.13 is an embodiment of an adaptive shock absorber with an autonomous arrangement of an adjustable solenoid valve.

The shock absorber (figure 1) consists of a concentrically arranged outer tube-tank 1 and a working cylinder 2, which are mounted on top of the guide 3 of the rod 4 connected to a monolithic (not containing valves or throttles) piston 5. The piston 5 is placed movably in the working cylinder 2 In the lower part of the guide 3 there is a bypass valve 6 made, for example, in the form of an elastic plate of low stiffness. A similar bypass valve 7 is located at the base of the working cylinder 2.

The working cylinder 2 forms with the tube-tank 1 and the guide 3 an annular cavity 8, which, through the window 9, communicates with the outlet 10 of the adjustable solenoid valve 11.

On the inner surface of the working cylinder 2, in its peripheral part, through working windows are made, upper 12 and lower 13. Working windows in plan can have a triangular profile - figa, 2b, square profile - figv, rectangular profile - fig. 2g etc., or they can be made in the form of a “groove” - holes of variable cross-section (Fig. 3), the inner profile 14 of which has the same appearance as in Fig. 2, and the outer - 15 - can have circle shape. The profile of the working windows 12 and 13 is symmetrical with respect to each other and is selected on the basis of the need to implement in each case the required law of movement of the rod when it approaches extreme, boundary positions.

In the cavity 8, with the help of a closed element 16 (for example, a “ring” of rectangular cross section), a limited closed cavity 17 is selected. It is formed by the cylindrical surfaces of the working cylinder 2, the tank tube 1 and the closed element 16. The cavity 17 covers and combines the working windows 12 and 13 the working cylinder 2 and the window 18 of the tank tube 1.

Due to the presence of a closed cavity 17, the over-piston cavity 19 is communicated through the window 18 of the reservoir tube 1 with the inlet 20 of the adjustable electromagnetic valve 11 through the upper working window 12. At the same time, the under-piston cavity 21 also communicates with the closed cavity 17 through the lower working window 13 and, further , through the working window 12 - with the over-piston cavity 19, and through the window 18 of the tube-reservoir 1 and the inlet 20 of the adjustable electromagnetic valve 11 - with the input cavity 22 of the adjustable electric omagnitnogo valve 11. On the main window 13, the bypass valve 23 is installed.

The shock absorber with the help of nodes 24 and 25 (for example, eyes) is attached to the corresponding suspension elements of vehicles.

The thickness H of the piston 5 must be greater than the height H _{1 of the} working windows:

$$H>H_{\mathrm{one}}.\left(\mathrm{one}\right)$$

Adjustable solenoid valve 11 (figure 4) in functional design is a differential-type hydraulic valve with electromagnetic control. It consists of a housing 11, and placed in the housing of the locking and regulating unit and the control electromagnet.

The locking and regulating unit includes a guide sleeve 26, on the outer cylindrical surface of which a valve flap 27 is installed, made in the form of a cylindrical annular sleeve that can freely move along its longitudinal axis. On the inner cylindrical surface of the guide sleeve 26 there is a control flap 28, also made in the form of a cylindrical annular sleeve, which can freely move along its longitudinal axis.

The control electromagnet includes a coil 29, to the terminals 30 of which a control signal is supplied — control current I. The armature 31 of the electromagnet is integral with the plunger 32.

The control flap 28 is pressed by the spring 33 by means of the pusher 32 to the armature 31. Thus, the axial position of the control flap 28 is limited, for example, by stops - pins 34 and 35.

The axial movement of the valve flap 27 is limited, for example, by stops - pins 36 and 37. In this case, the valve flap 27 is pressed against the stop 36 by a spring 38.

An axial groove 39 is made on the outer surface of the armature 31, through which the cavity 40 communicates with the cavity 41. In turn, the cavity 40, through, for example, the windows 42 in the control flap 28, communicates with the output cavity 43 of the adjustable electromagnetic valve 11 connected to the outlet 10 adjustable solenoid valve 11.

On the lateral cylindrical surface of the guide sleeve 26, through segment tangential grooves — throttle 44 and valve 45 — are made. Two grooves are marked on the diagram, but in real designs there can be several, depending on the type of shock absorber operating characteristic required. Similar grooves 46 and 47 are provided in the control flap 28. In the valve flap 27 there are only valve grooves 48. The radial channel 49 connects the cavities 43 and 50.

Cavities 40, 43, 41 and 22 are filled with oil.

The shock absorber works as follows.

In the rebound phase, when the rod 4 and piston 5 are moved upward, as shown in FIG. 1, oil from the over-piston cavity 19 is displaced by the piston 5 through the upper working window 12 into the closed cavity 17, and then passes through the window 18 and the inlet 20 of the adjustable electromagnetic valve 11 into the inlet cavity 22 of the adjustable solenoid valve 11, then, due to the throttle grooves 44 and 46 (Fig. 4), into the outlet cavity 43 of the adjustable solenoid valve 11. From the outlet cavity 43, oil passes through the outlet 10 and the window 9 into the cavity 8 the shock absorber itself. Since the cross-sectional area of the passage openings of the throttle grooves 44 and 46 is relatively small, the oil pressure in the cavity 22 is much higher than in the cavity 43. At the same time, a “damping” force that prevents the above-mentioned rod movement begins to act on the piston 5 from the oil side in the cavity 19 4 up.

Note that due to the occurrence of rarefaction in the subpiston cavity 21, the bypass valve 7 opens and the increase in oil volume in the subpiston cavity 21 is compensated by its entry from the cavity 8, which is connected to the outlet 10 of the adjustable electromagnetic valve 11. Since the oil pressure in the cavity 19 (i.e. i.e. in the inlet 20 and in the inlet cavity 22 of the adjustable solenoid valve 11) is much larger than in the cavity 8 (which is connected to the outlet 10 of the adjustable solenoid valve 11), then usknoy valve 6 throughout the rebound phase closed. For the same reason, the bypass valve 23 is also closed.

This process continues until the upper end plane 51 of the piston 5 reaches position II (corresponding to the level of the lower boundary of the upper working window 12), at which the working window 12 is still fully open to a height of H ₁ . With further movement of the piston upward, the working window 12 begins to gradually overlap with the piston 5, i.e. the height h of the lumen of the working window begins to decrease from the value of H ₁ to 0, and the area F of the cross section of the working window - from the value of F _max to 0 (figure 5).

We emphasize that when the plane 51 of the piston 5 reaches position II-II, the working window 12, due to (1), is completely closed, i.e.

, и $$F=0.\left(2\right)$$

$$h=0$$

, and $$F=0.\left(2\right)$$

In this case, further movement of the piston upwards, due to the incompressibility of the oil, is impossible. This eliminates the possibility of "breakdown of the shock absorber" at the end of the rebound phase, i.e. the possibility of collision of the plane 51 of the piston 5 with the guide 3 of the rod 4 with a sharp stretching of the shock absorber, which may occur, for example, when the vehicle moves at high speed on rough roads, in particular, when the wheel gets into the road pit.

Thus, the position II-II of the plane 51 of the piston 5, corresponding to the upper face of the working window 12, determines the upper boundary position of the piston 5.

In the compression phase, when the rod 4 and piston 5 are moved down, as shown in FIG. 6, the oil opens the valve 23 under the pressure of the piston and through the working window 13 is displaced from the sub-piston cavity 21 into the closed cavity 17, making up, due to the presence of the working window 12, increasing the volume of the cavity 19. At the same time, the part of the oil corresponding to the volume of the rod 4 sliding into the cavity 19 enters through the window 18 and the inlet 20 of the adjustable solenoid valve 11 into the inlet cavity 22 of the adjustable solenoid valve 11.

The subsequent oil path is the same as in the previous rebound phase.

The process described above is repeated until the lower end plane 52 of the piston 5 reaches position III-III (FIG. 1), corresponding to the level of the upper boundary of the lower working window 13, at which the working window 13 is still fully open to a height of H ₁ . With the further movement of the piston downward, the working window 13 (similar to that which occurred at the rebound phase with window 12) begins to gradually overlap with the piston 5, i.e. the height h of the lumen of the working window begins to decrease from the value of H ₁ to 0, and the area F of the cross section of the working window - from the value of F _max to 0 (figure 5).

We emphasize that when the plane 52 of the piston 5 reaches position IV-IV, the working window 13, due to (1), is completely closed, i.e. the relation (2) holds. In this case, the further movement of the piston down, due to the incompressibility of the oil, is impossible. This eliminates the possibility of "breakdown of the shock absorber" at the end of the compression phase, i.e. excludes the possibility of collision of the plane 52 of the piston 5 with the base of the working cylinder 2 with a sharp compression of the shock absorber, which may occur, for example, when the vehicle moves at high speed on rough roads, in particular, when the wheel hits a hummock.

Thus, the position IV-IV of the plane 52 of the piston 5, corresponding to the lower edge of the working window 13, determines the lower boundary position of the piston 5.

It should be noted that during the entire compression phase, except for its initial moment, the bypass valve 6 is closed, since the oil pressure in the cavities 21, 22 and 17, i.e. in the inlet cavity of the adjustable solenoid valve 11, more than in the cavity 8, which is connected to the outlet 10 of the adjustable solenoid valve 11. For the same reason, the bypass valve 7 is also always closed during the entire compression phase.

Consider the very initial moment of movement of the piston 5 in the compression phase from the extreme upper position, when its plane 51 still occupies the position II-II (Fig.7). At this moment, a certain pressure is created in the over-piston cavity 19, under the action of which the bypass valve 6 opens and the increase in the volume of the cavity 19 is compensated by the influx of oil through the window 53 from the cavity 8. But this situation occurs only at the indicated moment, thus avoiding the “gap of volume” the oil in the cavity 19. At subsequent times, the oil in the cavity 19 will enter through the opening window 12 as described in the analysis of the shock absorber in the compression phase.

It must be borne in mind that to prevent air from entering the cavity 19, the oil level in the shock absorber should not be lower than the position indicated by the cross section V-V (Fig. 1).

Note that choosing one or another form of working windows 12 and 13, it is possible to form one or another law of piston movement when it approaches its extreme positions II-II and IV-IV. In particular, choosing a form corresponding to the figure in Fig. 2a in window 12, a smoother decrease in the cross-sectional area F of the working window can be realized (curve 5.1. In FIG. 5), and therefore a smoother increase in the shock absorber resistance, i.e. more effective damping of dynamic loads in the vehicle suspension.

It should be noted that in both of the two phases discussed above, in the compression phase and the rebound phase, the shock absorber, in the absence of a control action from the control unit 54 to the adjustable solenoid valve 11, which is carried out in the form of a control current I supplied to contacts 30 ( the control flap 28 remains stationary, in the extreme upper position shown in figure 4) of the coil 29, i.e. under the condition

$$I=0\left(3\right)$$

works like conventional well-known non-adjustable shock absorbers. In this throttle mode, shown in figure 4, is implemented due to the special selection and profiling of the throttle grooves 44 and 46.

With an increase in piston speed 5, i.e. with increasing oil pressure in the input cavity 22 of the adjustable solenoid valve 11, at a time when the total force

$${\mathrm{<figure-callout\; id="27"\; label="N"\; filenames="00000013.png,00000015.png"\; state="\{\{state\}\}">N</figure-callout>}}_{27}=\left({\mathrm{<figure-callout\; id="2"\; label="d"\; filenames="00000012.png,00000013.png"\; state="\{\{state\}\}">d</figure-callout>}}_2^2-d_{\mathrm{one}}^2\right)\left(P_{22}-P_{43}\right)\pi /\mathrm{four}-N_{38}\left(\mathrm{four}\right)$$

on the valve flap 27 will become positive, i.e.

, $${\mathrm{<figure-callout\; id="27"\; label="N"\; filenames="00000013.png,00000015.png"\; state="\{\{state\}\}">N</figure-callout>}}_{27}>0$$

,

the valve flap 27 will begin to automatically move downward, overcoming the action of the spring 38 and opening the valve grooves 45 (Fig. 8) of the guide sleeve 26. At this point, the throttle-valve mode of operation of the shock absorber will already take place.

Here: P ₂₂ , P ₄₃ - oil pressure in the cavities 22 and 43, respectively; N ₃₈ - force from the side of the spring 38 on the valve flap 27.

Note that the throttle-valve mode is realized due to the corresponding profiling of the valve grooves 45, 47 and the selection of the stiffness of the spring 38 of the valve flap 27. In the throttle-valve operating mode of the shock absorber, oil from the inlet cavity 22 enters the outlet cavity 43 as through the throttle grooves 44 of the guide bushings 26, and through the valve grooves 45.

With a further increase in piston speed 5, i.e. with a further increase in oil pressure in the input cavity 22 of the adjustable solenoid valve 11, the valve flap 27, overcoming the force of the spring 38, will occupy the lowest position limited by the stop 37 (Fig. 9). When this valve grooves 45 are fully open.

Thus, the adjustable solenoid valve 11 with a constant control action from the control unit 54, i.e. when condition (3) is fulfilled, it works like a regular unloading valve in a conventional unregulated shock absorber. Namely this option of its operation is considered in Fig. 4, Fig. 8 and Fig. 9 .: if the control current I at contacts 30 is equal to zero, then the armature 31 under the action of the spring 33 occupies an extreme upper position, limited, for example, by a stop 34. When this control flap 28 is in its highest position (figure 4), in which the throttle grooves 44 and valve grooves 45 are fully open.

We emphasize that mode (3) also corresponds to the Fail Safe mode (emergency traffic program) - one of the standard shock absorber operation modes. It occurs, for example, when the control unit 54 fails, in which the control action is forcibly “nullified”.

It should be noted that the proposed shock absorber, in contrast to the case considered above (3), allows in a wide zone, depending on road conditions, to adjust its performance - the dependence of the force P on the rod on the value of the rod velocity V (Fig. 10);

$$P=P\left(V\right).\left(5\right)$$

Those. in terms of functionality, it is an adaptive shock absorber. This is ensured by external influence from the control unit 54, by changing the value of the control current I at the contacts 30 of the coil 29.

Consider these more general modes of operation of the shock absorber when the control current I is supplied to the contacts 30 of the coil 29 from the side of the control unit 54, i.e. consider cases when

$$0<I\le I_{\max }.\left(6\right)$$

As the control current I increases at contacts 30, the armature 31, and with it the control flap 28, overcoming the resistance of the spring 33, starts to move down until the electromagnetic force at the armature is balanced by the resistance force of the spring 33. In this case, the valve 44 and throttle 45 grooves begin to partially overlap (11), thereby increasing the hydraulic resistance in the valve. The latter circumstance, in turn, leads to an increase in the degree of damping of the shock absorber. Finally, with $$I=I_{\max }\left(7\right)$$

the armature 31, and with it the control flap 28, occupy the lowest position (Fig. 12), limited by the stop 35. In this case, the valve 44 and throttle 45 grooves are completely closed. The inlet cavity 22 is isolated from the outlet cavity 43. The movement of oil from the shock absorber itself to the valve is blocked and the movement of the piston and rod are blocked. There is a "blocking mode" of the shock absorber when it turns into a single hard link.

The locking mode (7) is an important operational advantage of the proposed shock absorber, which distinguishes it from the known traditional schemes. It is necessary, for example, to stabilize the movement of a vehicle in corners, during rolls, as well as during sharp braking and acceleration - i.e. when "pecking" the vehicle.

Thus, increasing the value of the control current I within the ranges (3), (6), it is possible to steplessly change the degree of damping of the shock absorber (Fig. 10). In case (3), the most “soft” characteristic takes place (curve 10.1), as the control current I increases, the degree of damping of the shock absorber increases (curves 10.2 and 10.3, respectively) and, finally, in case (7), the characteristic becomes “absolutely rigid "- the shock absorber is blocked.

Note that the Comfort mode, which is implemented in the prototype by force, "manually" in the proposed shock absorber corresponds to the case (3). In the proposed shock absorber, it can also be implemented in a forced manner, "manually" by fixing the value of the control current I = 0. A similar situation exists for the prototype modes “Normal” and “Sport”.

It should be noted that in addition to the method described above for directly mounting the adjustable solenoid valve 11 to the shock absorber tube 1, an autonomous arrangement of the adjustable solenoid valve shown in FIG. 13 is also possible. In this case, the cavity 17 of the shock absorber communicates with the inlet cavity 22 of the adjustable solenoid valve 11 through the pipe 55, and the cavity 8 communicates with the output cavity 43 of the adjustable solenoid valve 11 through the pipe 56. In this case, the adjustable electromagnetic valve 11 can no longer be placed directly on the shock absorber, and in another, more suitable place. The workflow of the shock absorber is not changed. To prevent air from entering the cavity 19, a tube 57 is provided that connects the cavity 19 to the lower part of the cavity 8.

Thus, the use of the proposed design solution of the shock absorber will increase its reliability and durability by eliminating the possibility of breakdown of the shock absorber during its operation, simplify and, therefore, reduce the cost of the design by eliminating the special Fail Safe valve for implementing the “Fail Safe” mode, and expand the shock absorber’s functionality for due to the possibility of implementing a blocking mode.

Claims (2)

1. Adaptive shock absorber of a vehicle suspension, comprising an outer tube-reservoir fixed in the rod guide with an annular cavity formed by a working cylinder fixed in the rod guide of the concentric tube-reservoir, inside which a monolithic piston with a rod movable in the rail is movably placed, and in the walls of which , in its upper and lower parts, through, respectively, the upper and lower working windows are made, and in the base and guide, bypass valves are installed, as well as The main control unit and an adjustable differential solenoid valve installed in the tank tube, including a sequentially placed control electromagnet, functionally connected to the control unit and consisting of interconnected coils and armature with a pusher, an inlet cavity, and a concentric valve damper located in it, guiding a sleeve controlling the shutter, characterized in that in the annular cavity by means of a closed element, a limited closed cavity is selected connecting I have upper and lower working windows with an inlet cavity of an adjustable solenoid valve, a bypass valve is installed on the lower working window, the valve flap is movably mounted on the outer surface of the guide sleeve, on the inner cylindrical surface of which the control flap is movably fixed, pressed against the follower by a spring, the valve flap is fixed on guide sleeve using a spring on the cylindrical lateral surfaces of the guide sleeve, valve flap and control flap in Full segment through tangential slots. 2. The adaptive shock absorber according to claim 1, characterized in that the limited closed cavity is communicated by means of a pipeline with an inlet cavity of an adjustable electromagnetic valve, and the annular cavity of a shock absorber is communicated by means of a pipeline with an outlet cavity of an adjustable electromagnetic valve.

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