DE4320446A1 - Shock absorber - Google Patents

Description

State of the art

The invention relates to a shock absorber for motor vehicles Influencing a relative movement of two moving relative to each other real masses. One of the two masses is a vehicle body and the each other mass is a rotating vehicle wheel Wheel carrier.

There are shock absorbers with a piston piercing a cylinder rod to which a piston is attached, which is axially in a cylinder is slidably mounted and an interior of the cylinder in one divides upper workspace and into a lower workspace. Further this shock absorber is partially filled with a gas storage space. A tension damping valve is located in the piston and a check valve. The storage space is over another Check valve and a pressure damping valve with the second, connected working space facing away from the piston rod. In the extension stroke the check valve in the piston is closed and that from which it Most of the work space displaced flows over the train damping throttle in the second work space and at the same time can from the Storage space pressure medium via the second check valve in the flow into the second work area. That is during a run-in stroke  second check valve between the second work space and the Storage space closed and the Vo displaced by the piston rod lumen flows into the storage space via the pressure damping valve. At the same time, pressure medium can be in the piston via the first one check valve from the second work area to the first area get to the working room. The traction damper determines the extension stroke throttle in the piston damping the shock absorber and during egg The retraction stroke determines the pressure damper connected to the cylinder the damping of the shock absorber. Such a known one Shock absorbers are commonly referred to as twin-tube shock absorbers. Such a shock absorber is, for example, in the Reimpell book "Chassis technology: shock absorbers", 1st edition 1983, Vogel-Buchverlag Würzburg, shown on page 22.

Such a shock absorber is preferably used in passive, i.e. H. non-controllable shock absorbers. Should the damping this Shock absorber can be controlled, so it is disadvantageous that for the Extension stroke responsible damping valve in the piston and that for the Retraction stroke responsible pressure damping valve arranged on the cylinder is. This has the disadvantage that electri to both valves cal lines must be laid. Because the piston or pistons rod moves relative to the cylinder is a suitable one Multiple laying of the electrical lines is not possible or must be with early loss of controllability due to de perfect electrical cables.

In order to avoid the problem just described, an attempt was made to for the retracting stroke and the valve responsible for the extending stroke in to move the piston. Such a shock absorber is in the DE-A-32 46 697 shown. However, this shock absorber only has a lot limited uses, because with this shock absorber problem-free, sensible change in damping force not possible is. If with this shock absorber during a run-in stroke Damping is too large, the lower Ar  Work space too much pressure medium through a hole in the storage space pressed and in the upper annular work space can not do enough Follow the pressure medium so that the pressure in this upper working space falls too much and the pressure medium located there foams, d. H. Gas bubbles can escape from the pressure medium. This is especially uncomfortable because at the beginning of a Ausfahrhubes first this space created by the outgassing strikes before the cushioning can start again. With this Shock absorber is the maximum adjustable damping for the entry stroke very limited.

There is also a shock absorber that tries to do that Outgassing or foaming of the pressure medium during the run-in to avoid hubes in the rod-side work area. Such Shock absorber shows the DE-A-33 03 293 or the same Pa US 45 61 524 belonging to the tent family. This shock absorber requires each a lot of construction work and is therefore very expensive. In addition, that with this shock absorber an additional bottom control slide is required, which must be fitted very precisely and the smallest manufacturing defects and / or dirty Pressure medium can tend to jam. The additional control spool is located between the floor-side work area and the dining room room. This shock absorber is intended to be used during a run-in stroke Print media from the storage space to the top, the piston rod around can enter the working area. During an extension stroke however, the opposite way may be blocked. To do this accordingly control is the additional located in the bottom area of the cylinder Control spool necessary.

Advantages of the invention

The shock absorber according to the invention with the features of the main In contrast, saying has the particular advantage that by a  simple, reliable measures foaming of the print medium or prevents outgassing of gas dissolved in the pressure medium becomes.

The measures listed in the subclaims provide for partial further training and improvements of the main claim specified shock absorber possible.

The proposed shock absorber advantageously enables Arrangement of both during the retracting stroke and during the Ausfahrhubes effective control valve device in the piston without through this measure the risk of foaming of the print medium can arise.

The pressure medium can flow from the second work area via the valve device into the connection leading into the first work area. This occurs from the piston rod during a run-in stroke pushed volume into the storage space.

The throttle device through which the pressure medium flows when the valve device must flow into the storage space ensures an increase in the pressure in the connection, which has the advantage that the print medium over the connection with slightly raised pressure gets into the first working area, so that even in cross section tightly dimensioned connection a foaming of the print medium is prevented.

If you consider the pressure medium flowing through the throttle device not at the beginning of the connection, but in the course of this connection branches off, this leads with little effort and with little Throttling the print medium to safely raise the pressure of the pressure flowing into the first work space via the connection mediums.  

You can get around the inner jacket that holds the two work rooms Pipe a second jacket pipe at a distance and the ver bond through the formation between these two jacket tubes Pass the space through. This offers the advantage of simple fro possibility and the connection increases the construction volume of the The shock absorber is advantageously only very insignificant.

If you consider the distance between these two jacket pipes, in cross section seeks to arrange with different radial distance from each other net, with the same free cross-sectional area between the two jacket pipes, the resistance for that through the connection flowing pressure medium advantageously particularly low.

drawing

Selected, particularly advantageous embodiments of the shock absorber are shown in simplified form in the drawing and explained in more detail in the following description. There, Figs. 1 to 6 depending on an embodiment.

Description of the embodiments

The shock absorber according to the invention can always be used if the relative movement of two masses movable relative to each other should be able to be influenced and if this influencing should be controllable should. The shock absorber is used in particular in motor vehicles Influencing between a vehicle body and a driving wheel carrier carrying the tool wheel.

Figs. 1 to 4 show the essence of the invention. In order to be able to present the essentials as large as possible with a reasonable amount of space, various gaps within the shock absorber are shown shortened. In particular, the stroke of the shock absorber relative to the diameter of the shock absorber can be substantially larger than it appears when looking at FIGS. 1 to 4. To be able also to the essence of the invention represent as large as possible, from 1 to 4 and 6 is always displayed only the left half of the shock absorber in FIGS.. It is easy for a person skilled in the art to supplement the other half of the shock absorber accordingly.

Fig. 1 shows a cylinder 2 of a shock absorber. The cylinder 2 comprises an inner jacket tube 4 , a middle jacket tube 6 , an outer jacket tube 8 , a rod end 10 and a bottom end 12th An inner space is formed between the two ends 10 , 12 within the inner casing tube 4 of the cylinder 2 . In the interior, a piston 14 is axially slidably mounted on the inner jacket tube 4 . The piston 14 is connected to a piston rod 16 a related party. The piston rod 16 penetrates the rod end 10 and leads out of the interior of the cylinder 2 . In the region of the end facing away from the piston 14 , the piston rod 16 is connected to a first mass 18 . The cylinder 2 is coupled or connected to a second mass 19 . The first mass 18 is, for example, a vehicle body and the second mass 19 is, for. B. a wheel carrier, such as. B. a vehicle axle on which a vehicle wheel, not shown, is mounted.

The piston 14 divides the interior of the cylinder 2 into a first working space 21 and a second working space 22 . The first Ar beitsraum 21 is located between the rod end 10 and the piston 14 and is penetrated by the piston rod 16 . The second working space 22 is located between the piston 14 and the bottom end 12 . A provided between the rod end 10 and the piston rod 16 seal 24 seals the first Ar beitsraum 21 from the outside. A arranged on the outer periphery of the piston 14 guide element 26 provides a seal between the piston 14 and the cylinder 2 and thus ensures that in a possible gap between the piston 14 and the casing tube 4 of the cylinder 2, no pressure medium between the two working spaces 21 and 22 can flow back and forth.

The jacket tubes 4 , 6 , 8 have the shape of circular, cylindrical tube pieces. Each of these jacket tubes 4 , 6 , 8 extends between the two ends 10 , 12 and is attached pressure-tight in the region of the two ends 10 , 12 . The three casing pipes are inserted into each other and the inner diameters and outer diameters of the three casing tubes 4, 6, 8 are so dimensioned that between the inner jacket tube 4 and the middle casing tube 6, a gap 28 and between the intermediate jacket tube 6 and the outer tubular jacket 8, a storage space 30 remains free.

The working spaces 21 , 22 contain a pressure medium, preferably an oil. The storage space 30 is partly filled with the pressure medium and partly with a gas. A liquid surface 31 is formed between the pressure medium and the gas. As a modification to the illustrated embodiments, a membrane separating the gas from the pressure medium or z. B. a separating piston is arranged.

The gas in the storage space 30 is preferably biased with a bias pressure.

There is a control device 32 in the area of the first mass 18 . A control line 34 leads through the piston rod 16 to a control valve device 36 arranged in the region of the piston 14 . A control passage 38 leads through the piston 14 and opens on the one hand into the first working space 21 and on the other hand into the second working space 22nd The control valve device 36 is located in the course of the control passage 38 .

The control device 32 is, for example, an electronic circuit and the control line 34 is, for example, an electrical line. Depending not shown sensors or in response setpoints entered or inputted Pro program, the control device 32 can be via the control line 34 of the control valve device 36 transmit control signals. With these control signals, the control valve device 36 can be adjusted who. Depending on this adjustment, the working space 21 flowing from the first working chamber 21 through the control passage 38 into the second working space 22 is more or less throttled. Also, the strö from the second working chamber 22 in the first working chamber 21 Mende print medium is more or less throttled in dependence on the control signals by means of the control valve device 36th The control valve device 36 can be designed such that the pressure medium flowing through the control passage 38 is throttled to the same extent in the two directions and an adjustment of the throttling means in one direction a correspondingly equal adjustment of the throttling in the other direction. The Steuererventileinrich device 36 can also be designed so that the flow of the pressure medium through the control passage 38 in the two directions can be throttled independently of one another and can be adjusted independently of one another.

In the area of the bottom end 12 of the cylinder 2 there is a valve device 40 . This includes, for example, a Rückschlagven valve 41 and a valve 42nd A check valve 43 is located in the area of the rod end 10 of the cylinder 2 . In the shock absorber proposed here, there is a connection 50 . A passage 46 or 46 a, 46 b connects the valve device 40 to the second working space 22 . Since the passage in the exemplary embodiment shown comprises two parallel channels, the passage is designated 46a and 46b in the drawing. Another passage 47 leads from the valve device 40 into the intermediate space 28 , and a further passage 48 connects the valve device 40 with the storage space 30 . In the illustrated embodiment, the passages 47 , 48 are laid so that they run within part of their distance within a common channel. A passage 49 leads from the intermediate space 28 into the first working space 21 . The check valve 43 is located in the course of this passage 49 .

The connection 50 leads, starting from the second working space 22 , through the valve device 40 , through the passage 47 , through the intermediate space 28 , through the passage 49 and through the Rückschlagven valve 43 in the first working space 21st The check valve 43 in the United course of the connection 50 is arranged so that the pressure medium is largely not throttled by the check valve 43 when flowing into the first working space 21 , but the check valve 43 allows essentially no escape of pressure medium from the first working space 21 through the Connection 50 . Small leaks in the reverse direction through the check valve 43 are irrelevant for the function of the shock absorber, which allows the use of a very simple check valve 43 .

The valve device 40 is designed so that the pressure medium when flowing from the direction of the second working space 22 through the valve device 40 is throttled or biased in a predetermined manner, but the valve device 40 allows a largely unthrottled flow of pressure medium from the direction of the storage space 30 in the second work space 22 .

In the exemplary embodiment shown in FIG. 1, the valve device 40 comprises the check valve 41 and the valve 42 . This is only an example and was chosen in particular to make the drawing as clear as possible. One could just as well realize the check valve 41 and the valve 42 with a single element. For example, a so-called plate valve could be used for this, which allows the pressure medium to flow largely unthrottled in one direction and the pressure medium is throttled to a predeterminable amount in the other flow direction. Those skilled in the art are familiar with such valves, so that a detailed description of how the valve is constructed in detail is not necessary.

During a run-in stroke, sometimes referred to as a compression stage, the two masses 18 , 19 move towards one another. In the case of an extension stroke, sometimes also referred to as a rebound, the two masses 18 , 19 strive apart.

If the shock absorber is in the retracting stroke, the piston rod 16 is increasingly immersed in the cylinder 2 , the volume of the most working space 21 being greater and the volume of the second working space 22 being reduced. Since the piston rod 16 dips into the interior of the cylinder 2 during the insertion stroke, the volume of the first working space 21 does not increase to the extent that the volume of the second working space 22 decreases. Therefore, part of the pressure medium must escape into the storage space 30 during the retracting stroke. During an extension stroke, the piston rod 16 emerges from the interior of the cylinder 2 , the volume of the second working space 22 becoming greater than the volume of the most working space 21 . Therefore, a part of the pressure medium must be able to flow from the storage space 30 into the working space 22 in the extension stroke. This is done in the exemplary embodiment shown in FIG. 1 through the passage 48 via the valve device 40 , the pressure medium in the special illustrated embodiment from the storage space 30 being able to flow almost unthrottled through the check valve 41 of the valve device 40 into the second working space 22 . During a run-in stroke, the pressure medium flowing from the second working space 22 into the storage space 30 is throttled, the throttling of the pressure medium taking place in the special embodiment shown by the prestressed valve 42 of the valve device 40 .

During a drive-in stroke, pressure medium flows from the second working space 22 through the control valve device 36 into the first working space 21 , being throttled by the control valve device 36 with the help of the control device 32 in a predeterminable, changeable manner. During an extension stroke, pressure medium flows out of the first working space 21 through the control valve device 36 . Corresponding to the predetermined signals from the control means 32 driving the print medium is throttled thereby, and flows into the second working chamber 22nd

During a Einfahrhubes arises in the through the control passage 38 from the second working chamber 22 in the first working chamber 21 streaming pressure medium caused by the control valve device 36 forth and influenceable pressure difference. And there is also a pressure difference within the valve device 40 by the pressure medium flowing from the second working space 22 in the direction of the storage space 30 . If the pressure difference in the control valve device 36 is smaller than the pressure difference in the region of the valve device 40 , then nothing flows through the connection 50 into the first working space 21 . The control valve device 36 can for example vary between 0 bar pressure difference and a pressure difference which is almost the same size as the pressure difference in the valve device 40 . A problem-free adjustment of the control valve device 36 is possible within this range.

If during a run-in stroke the pressure medium through the control valve device 36 is throttled more than in the area of the valve device 40 , then without the connection 50 the pressure in the first working space 21 would drop so far that the working medium 21 located in the first working space foams or there is a risk that dissolved gas would escape from the pressure medium located within the first working space 21 . This danger does not exist in the shock absorber proposed here, because, because of the connection 50 leading into the working space 21, pressure medium coming from the storage space 30 or coming from the second working space 22 can flow into the first working space 21 . Since the check valve 43 in the connection 50 throttles the pressure medium at most un substantially, there is pressure in the first working chamber 21 in each case at least the prevailing in the storage chamber 30 . Another measure against outgassing or foaming in the working space 21 is that the gas in the storage space 30 is provided with an increased bias pressure. However, this measure can only be used to a very limited extent for several reasons, because the increased pretensioning pressure includes z. B. increases the friction between the seal 24 and the piston rod 16 and because the increased bias pressure drives the piston 14 towards the extension stroke.

During an extension stroke, the check valve 43 is closed within the connection 50 and the shock absorber works in the same way as a previously known shock absorber, so that the function of the shock absorber for this direction of movement does not need to be explained.

Fig. 2 shows a further advantageous embodiment of the shock absorber.

In all figures, the same or equivalent parts are provided with the same reference numerals. The following exemplary embodiments are largely constructed in the same way as the first exemplary embodiment according to FIG. 1, except for the deviations which are essentially specified below. Details of the various exemplary embodiments can be combined with one another.

In the embodiment shown in FIG. 2, the check valve 43 located in the connection 50 is not arranged in the rod end 10 but in the region of the bottom end 12 , namely in the passage 47 between the valve device 40 and the intermediate space 28 .

Furthermore, the control valve device 36 comprises two electrically adjustable control valve devices 36 a and 36 b, wherein, for example, the control valve device 36 a is responsible for the insertion stroke and the control valve device 36 b for the extension stroke. Two control passages 38 a and 38 b connect the two working spaces 21 , 22 . The control valve device 36 a is located in the course of the control passage 38 a. Accordingly, the control passage 38 b through the control valve device 36 b.

Furthermore, in deviation from Fig. 1 in Fig. 2, the return check valve 41 and the valve 42 of the valve device 40 are combined in a single unit, wherein in Fig. 2 for better understanding of the functioning of the valve device 40 symbolically a non-biased Check valve and a spring loaded check valve shows. The passage 46 connects the two th working space 22 with the valve device 40 .

FIG. 3 shows a further advantageous embodiment.

Compared to FIGS. 1 and 2, a throttle device 55 is also present in the embodiment shown in FIG. 3. The throttle device is located in the region of the bottom end 12 and is designed and arranged such that during a run-in stroke when the pressure medium is displaced from the second working chamber 22 by the valve 42 of the valve device 40 , the pressure medium displaced into the reservoir 30 additionally must flow through the throttle device 55 , where it is additionally throttled according to the design of the throttle device 55 . The Drosselein device 55 is designed or arranged so that the pressure medium flowing from the Ven tileinrichtung 40 through the connection 50 in the first working space 21 is not throttled by the throttle device 55 .

The throttle device 55 is preferably designed or arranged so that the pressure medium flowing from the storage space 30 through the valve device 40 into the second working space 22 is not influenced even during an extension stroke.

The throttle device 55 is arranged in the course of a channel 57 . The channel 57 opens into the connection 50 where the passage 47 leads into the intermediate space 28 . On the other hand, the channel 57 leads below the liquid surface 31 into the storage space 30 .

The throttle device 55 can be, for example, a simple, fixed cross-sectional constriction. But you can also use, for example, a spring-loaded Ven tilkörper pressed against a valve seat, with any predetermined throttle line and with a flow direction from the direction of Ventilein direction 40 in the direction of the storage space 30th

FIG. 4 shows a further advantageous embodiment of the shock absorber.

Compared to FIG. 3, channel 57 is missing in FIG. 4. Instead of the sen there is a passage 60 in FIG. 4. The passage 60 , coming from the intermediate space 28 of the connection 50 , leads below the liquid surface 31 into the storage space 30 .

As already explained above, depending on the operating state, pressure medium can flow from the second working space 22 through the connection 50 into the first working space 21 during a run-in stroke. Since it is not technically possible to make the free cross-section arbitrarily large in the course of the connection 50 , there is an inevitable pressure drop in the course of the connection 50 . Because the outer diameter of the shock absorber must not be too large, the free cross section of the space 28 should also be as small as possible. With a small free cross section of the connection 50 , the pressure drop which occurs in the course of the connection 50 is no longer negligible. At the end of connection 50 , in order to avoid oil foaming, the pressure of the pressure medium must not fall below a certain value. In order, despite not excessive throttling of the pressure medium through the Dros seleinrichtung 55 to obtain a sufficient pressure at the end of the fitting 50, it is advantageous not bond the leading through the throttle device 55 into the storage chamber 30 channel at the beginning of the Ver 50 but only there to branch off, where the pressure medium has already flowed through the connection 50 to some extent. It is particularly expedient if the length of the connection 50 between the branch into the passage 60 and the junction into the first working space 21 is as short as possible. On the other hand, considering the length of the passage 60 , it is also not necessary to branch the passage 60 directly at the end of the connection 50 .

So that as little gas as possible dissolves in the pressure medium, the passage 60 should open into the storage space 30 below half of the liquid surface 31 up to a certain inclination of the shock absorber.

In FIG. 4, the check valve 41 and the check valve 43 in the form of plate valves or so-called flutter of valves are formed. Valves of this type are frequently used in shock absorbers at various points. This type of valves is very low in mass, so that these valves can respond quickly to a reversal of the flow direction. In the approved direction of flow, these valves allow almost unrestricted flow of the pressure medium. They block quickly and reliably in the opposite direction of flow.

Fig. 5 shows a further advantageous embodiment of the shock absorber.

An essential difference compared to the vibration or shock absorbers described with reference to FIGS . 1 to 4 in the shock absorber according to FIG. 5 is that the piston 14 is provided on its end face facing away from the piston rod 16 with a compensating rod 17 , which in one with the liquid pressure medium, for example with pressure oil, filled compensation space or a storage space 30 'dips. The storage space 30 'is different from the embodiments according to FIGS. 1 to 4 to a certain extent enclosed by an extension of the outer casing tube 8 , which extends to the bottom end 12 of the cylinder 2 , the bottom end of the second working space 22 , which at the other embodiments by the bottom end 12 of the cylinder 2 is formed, in the embodiment of FIG. 5 is formed by a transverse wall 12 a, in which, as in the other embodiments, the valve device 40 is arranged low. In the embodiment under consideration, the middle jacket tube 6 , which was used in the other embodiments to limit the space 28 , is omitted, and the connection 50 comprises a connecting tube 64 , which extends from the upper end of the first work space 21 to the wall 12 a and in the area this wall 12 a via a check valve 43 corresponding check valve 43 'is connected to the compensation chamber 30 '.

In the embodiment according to FIG. 5, the connecting pipe 64 lies in a space 30 a between the inner casing tube 4 and the outer casing pipe 8 , this space 30 a having at least one opening 66 in the wall 12 a with the compensation or storage space 30 'Communicates. In its upper part, the intermediate space 30 a can be filled again with gas in accordance with the previously explained exemplary embodiments, as is indicated in FIG. 5 by the liquid surface 31 shown.

An important advantage of the shock absorber according to FIG. 5 is that by using the compensating rod 17 a greater spread can be achieved during a retracting stroke, whereby spread is to be understood as the bandwidth over which the damping force dependent on the piston speed can be adjusted in this way that there is a hard damping, a soft damping or an average value of the damping. Namely, while the theoretically possible when retraction stroke spreading is determined by the constructive often very limited choice of the ratio of piston area to the piston rod surface in the previously described shock absorbers, the balance bar 17 can be the shock absorber of FIG. 5 by the relatively free choice of the diameter in a set the desired damping characteristic over a wide range. Retraction stroke means that the shock absorber is compressed and is often referred to as the pressure stage. Large spread means big difference between minimum and maximum damping.

As Fig. 5 shows the use of the balance bar 17 also opens up a favorable possibility for the installation of a displacement sensor 68 which may be protruding into the hollow in the exemplary embodiment the balancing rod 17 and connected via feed lines 71 in the bottom end of the Zylin DERS. 2 In this case, the sensor 68 can cooperate, for example, with associated magnetic devices on the inside of the compensating rod 17 , which can be designed in the usual way and are therefore not specifically shown in the drawing.

Fig. 6 shows a further advantageous embodiment of the shock absorber.

1, the shock absorber of Fig. 6 differs from the shock absorbers according to FIG. To 4 in particular, characterized in that the central jacket tube 6 is absent and that the in the embodiments according to FIGS. 1 to 4 at the upper end of the storage space 30 between the intermediate casing tube 6 and the outer tubular jacket 8 is enclosed gas volume enclosed in a gas space 70, which is on the one hand by the outer casing 8 and the other side by a movable separating body 72, wherein the separator body 72 may be for example a movable wall and in the embodiment according to FIG. 6 is formed by a membrane, but instead of which, for example, a displaceable separating piston could be used. The gas in the gas space 70 is tensioned before, and the movable separating body 72 is struck by the pressure of the liquid pressure medium in the compensation or storage space 30 , which is connected on the one hand via the valve device 40 with the two th working space 22 and in Area of the rod-side end 10 of the cylinder 2 is connected to the first working space 21 via the check valve 43 . In the embodiment according to FIG. 6 1 includes in the embodiments according to FIGS. To 4 existing which eclip through the central jacket tube 6 bordered connection 50 so the memory space 30, on the one hand to the valve means 40 and on the other hand with the check valve 43 via corresponding channels the rod end 10 and the bottom end 12 of the cylinder 2 is connected. Here, the channel leading to the check valve 43 in the rod-side end 10 is extended to an annular groove 74 surrounding the piston rod 16 , which is sealed against the first working space 21 by means of a separate guide ring 76 , which can be slotted in the axial direction, which makes it possible to install it and also significantly improved the friction and leadership quality. Upwards or outwards, the annular groove 74 in the exemplary embodiment is sealed by means of a grooved ring 78 or another suitable seal, and on the outside of the grooved ring 78 a scraper 80 can also be provided, which moves the grooved ring 78 or the like in front of a retracting stroke Protects damage from dirt particles.

As is customary with shock absorbers, the inner jacket tube 4 can also have a circular, annular cross section in the case of the present shock absorber. The middle casing tube 6 can also have a circular, ring-shaped cross section. You can arrange the two jacket pipes 4 , 6 concentrically to each other. However, the two jacket tubes 4 , 6 can preferably also be arranged eccentrically to one another, the two central axes being shifted so far that the two jacket tubes 4 , 6 touch one another on one side. Dement accordingly, the free cross-section on the opposite side is correspondingly larger without the outer circumference of the shock absorber thereby changing. Due to the eccentric arrangement of the two jacket tubes 4 , 6 , the flow resistance through the space 28 is smaller than with a concentric arrangement of the two jacket tubes 4 , 6 , which is particularly noticeable particularly in the case of relatively viscous pressure medium. Depending on the pressure medium used and depending on the dimension of the space 28 , the flow resistance through the space with the eccentric arrangement of the two casing pipes 4 , 6 being as strong as possible can be smaller by a factor of 2.5 than if the two casing pipes 4 , 6 are arranged concentrically.

In the description of the exemplary embodiments, only a one-way check valve 43 is described. It goes without saying that a plurality of check valves 43 acting in parallel with one another can also be arranged. As a result, each of these check valves 43 can be made correspondingly smaller with the same total flow. The same applies to other components of the shock absorber, but in particular also for the storage space 30 , the devices 36 , 40 , 55 , the valves 41 , 42 , the connection 50 and the passages 46 , 47 , 48 , 49 , 57 , 60th .

Claims (16)

1. Shock absorber, in particular for motor vehicles, for influencing a relative movement of two masses which can be moved relative to one another, with a cylinder containing a pressure medium, with a piston rod and with a piston which divides an interior of the cylinder into a first working chamber and into a second working chamber, the cylinder is coupled to one of the two masses and the piston is axially displaceably mounted in the interior of the cylinder and is coupled to the other of the two masses via the piston rod penetrating the first working space, furthermore to a storage space, the storage space being provided by a valve device ( 40 ) is connected to the second work space and to a ver adjustable control valve device ( 36 ), via which the two work spaces can be connected to one another, characterized in that a connection ( 50 , 64 ) monitored by a check valve ( 43 , 43 ′) is provided, over the print medium the second working space ( 22 ) can be fed into the first working space ( 21 ) or from the storage space ( 30 30 ') into the first working space ( 21 ) via the valve device ( 40 ). 2. Shock absorber according to claim 1, characterized in that the control valve device ( 36 ) is arranged in the region of the piston ( 14 ). 3. Shock absorber according to claim 1 or 2, characterized in that the cylinder ( 2 ) has a piston rod ( 16 ) facing away from the bottom end ( 12 ) and that the valve device ( 40 ) is arranged in the region of this end ( 12 ). 4. Shock absorber according to one of claims 1 to 3, characterized in that the valve device ( 40 ) is formed in such a way that a largely unthrottled flow from the direction of the storage space ( 30 ) in the direction of the second working space ( 22 ) is possible, however, the pressure medium is throttled when flowing from the two th working space ( 22 ) in the direction of the storage space ( 30 ) in the region of the valve device ( 40 ). 5. Shock absorber according to one of the preceding claims, characterized in that a throttle device ( 55 ) is provided which is designed and arranged in such a way that the pressure medium throttled when flowing from the direction of the valve device ( 40 ) in the direction of the storage space ( 30 ) becomes. 6. Shock absorber according to claim 5, characterized in that a passage ( 60 ) in the course of the connection ( 50 ) from the connection ( 50 ) via the throttle device ( 55 ) leads into the storage space ( 30 ). 7. Shock absorber according to one of the preceding claims, characterized in that the connection ( 50 ) between two nested, cylindrical jacket tubes ( 4 , 6 ) is formed to extend. 8. Shock absorber according to one of claims 1 to 7, characterized in that the connection ( 50 ) is guided through a connecting tube ( 64 ). 9. Shock absorber according to claim 7, characterized in that the two casing tubes ( 4 , 6 ) are arranged at different radial distances from one another. 10. Shock absorber according to one of the preceding claims, characterized in that the connection ( 50 ) as the work spaces ( 21 , 22 ) enclosing the intermediate space ( 28 ) is formed. 11. Shock absorber according to one of the preceding claims, characterized in that the storage space ( 30 ) as the work spaces ( 21 , 22 ) surrounding annular space is formed. 12. Shock absorber according to claim 1, characterized in that the piston ( 14 ) on its end facing away from the piston rod ( 16 ) is provided with a compensating rod ( 17 ). 13. Shock absorber according to claim 12, characterized in that the storage space ( 30 ') is arranged in the axial extension of the second working space ( 22 ) and is separated therefrom by a wall ( 12 a) of the cylinder ( 2 ) containing the valve device ( 40 ) . 14. Shock absorber according to claim 13, characterized in that the check valve ( 43 ') is provided in the wall ( 12 a). 15. Shock absorber according to claim 14, characterized in that the connection ( 50 ) comprises a connecting tube ( 64 ) between the check valve ( 43 ') and the first working space ( 21 ). 16. Shock absorber according to one of claims 1 to 3, characterized in that the storage space ( 30 ) is separated by means of a movable separating body ( 72 ) from a gas space ( 70 ) containing a gas and that the connection monitored by the check valve ( 43 ) ( 50 ) is at least partially formed by the storage space ( 30 ) itself.