DE2323271A1 - WORK CYLINDER - Google Patents

Description

R. 14 3 8

March 28, 1973 Vd / Gü

Attachment to

Patent and

Utility model auxiliary registration

Working cylinder

The invention relates to a device for damping movement of the piston of a working cylinder at the end of the stroke with the help a throttle associated with the discharge space, which is located in a passage to a pressureless space.

In such a known working cylinder, a coaxial extension or damping space closes at the end of the cylinder ar., which is connected to an unpressurized space via a throttle point. There is a thickening on the piston rod, which dips into the damping chamber towards the end of the piston stroke, the displacement volume being displaced there by a sealing arrangement is blocked off from the working space of the working cylinder. The pressure medium displaced into the outside drawer space slowly flows through the throttle to the pressureless space, whereby the piston experiences a damping in the end phase of its movement.

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Such a device is probably simple in construction, but has the disadvantage that it requires a large construction space - the working cylinder becomes longer - it must also be specially built for such a device.

Zs is an object of the invention to provide a device of the opening to create the type mentioned, through which the working cylinder "structurally is not changed and can be attached to "any working cylinder" with little effort, too retroactively. The response behavior of the device should also be variable.

This object is achieved according to the invention in that the device essentially consists of a device specifically provided for this purpose There is a component that can be attached directly to the working cylinder or can be arranged separately from it, and that in this Component a piston valve is arranged, which controls the passage.

Such a cylinder is no longer than a cylinder without Damping device. Since this is a separate component, for example a throttle valve, it can be connected to any working cylinder be cultivated. This makes it particularly suitable for cylinders that are manufactured in large series, because such are partly built with and partly without a damping device. The subsequent attachment of a damping device to such a device standard working cylinder is very simple.

Further advantages of the subject matter of the invention emerge from the subclaims, the description and the drawing.

An embodiment of the invention is shown in the drawing. This shows in

Fig. 1 is a longitudinal section through a working cylinder with a damping device,

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Fig. 2 to 5 modifications of the damping device according to the embodiment of the i'i-g. ^Λ .

In lig. 1, ^ O denotes a working cylinder which is ^{closed on both sides by covers ΛΛ} and ^ 2. A central longitudinal bore 13 is formed in the cover ^Λ 2 , in which a piston rod 14 is guided so as to slide tightly. On the piston rod '4 a piston "" 5 is attached, which carries a sealing ring ^ 6 on its outer circumference, which is preferably made of plastic.

In the cover 12 a channel 17 is formed, which opens into the working space IS of the Arbeitsi-ylinder. A throttle bore 19, which emanates from a bore 20 in a connecting piece 2 ^A , which is attached to the outer circumference of the cylinder, also opens into this at a distance a from the side of the cover ^Λ 2 closing off the working space. The distance a of the throttle bore 19 of the working chamber side lid / wall is greater than der'Abstand b, the lid 12 to which the hand of the sealing ring ^{Λ ζ>} facing away from is formed by the cover-side piston end wall.

Near the cover 11 opens into a space 22 of the working cylinder a bore 23, which partly still runs in a nozzle 24, which is located on the outer wall of the working cylinder. At a distance c from the end of the cover on the workspace side 11 opens into the working space a throttle bore 25 which starts from a bore 26 which is formed in a connection piece 27 fastened to the outer wall of the working cylinder is. The piston rod ^ -4 has a protruding beyond the piston 15 Extension 28. The distance from the end of extension 28 to the cover is denoted by s.

Lines 29 and 30 lead from the connecting pieces 24 and 27 to a valve 31 which is part of the damping device. In the case of the valve a stepped bore 32 is formed, the small diameter bore part of the designation 32 ', the Large diameter bore part is labeled 32 ".

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The stepped bore 32 is closed by a housing cover 31 '. In the stepped bore 32 is a differential piston 33 out tightly sliding. Its violet part 33 'with a small Diameter slides in the elbow part 32 ', its EoIb ent part 33 "with it large diameter in the bore part 32 ". In the cover-side end of the bore part 32" opens a bore 34, which over the line 30 is connected to the bore 26. At the hole part 32 'facing the end of the bore part 32 "opens a bore 35" which via the line 29 with the bore 23 in Connection. On the large piston part 33 "of the Sluf piston 33 an Icrtsatz 36 is arranged, which ensures that between Always include: Print around 37 is present. On the piston part 32 'is also a Icrtsatz 39 formed, which ensures that even if the stepped piston is in its left end position, and a pressure space between its annular surface and the end of the bore part 32 ″ 40 remains. In the ind part 4 'of the bore part 32' is a Arranged spring 42, which acts on the stepped piston.

A bore 43 runs from the pressure chamber 40 to the end of the housing. from you lead a line 44 via a not shown. «Control valve to a container 45. From the bore 43 a channel leads 46 to the end part 4- "of the bore step 32 '. From the pressure chamber 37 <3-es Bore part 32 "is a stepped bore 47, in which a adjustable throttle body 48 is arranged. A bore 4Q branches off from the lower part of the stepped bore 47 and leads to the bore 43 leads. Hit the throttle body 47, the cross-section of the passage from the bore 47 to the bore 49 can be changed.

From the channel "7 and the bore 20 of the right end part of the working cylinder lead lines 50, 5 "to a valve 52, the is designed in the same way as the valve 3 ". It is therefore not described in more detail.

If the piston "" 5 is approximately in the middle of the working cylinder and it moves in the direction of the cover "• ' ¹ , this will be in space

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The pressure medium contained is displaced via the line 29, the botirung 35, the pressure chamber 40 and the bore 4-3 without resistance via the line 44 to the container 45. The flow is therefore without resistance, approximately the spring 42 pushes the stepped piston 33 into its right end position, in (Lev the extension JG rests on the cover 32 '. The flow from the bore 35 to the bore 43 is unthrottled. The pressure in space 22 corresponds practically the tank pressure; this also prevails in pressure chamber 37 ur .-. dpflanr / b continues there on the one hand via the throttle bore 25, the line 30 and the bore 3 ^Z -, on the other hand via the bores ^ 3, 49 and 47.

As soon as the piston Ί5 has reached the position shown in the drawing, aas means when the sealing ring G has slid over the throttle bore 25, the pressure in the space ″ -8 can propagate through the throttle bore 25 into the pressure chamber 37. As a result, the stepped piston 33 is displaced to the left, whereby it increasingly throttles the connection from the bore 35 to the bore 43. As a result, pressure medium can only flow out to the container 45 with a delay from the space 22 now forming the expulsion space, so that also in space 22 and thus a pressure builds up in pressure chamber 40 which, in cooperation with spring 42, tries to move stepped piston 33 to the right again against the pressure prevailing in pressure chamber 37. Between these opposing forces, an equilibrium is now established on stepped piston 33 , but the throttle vortex ^{is always maintained between the bores 35 1} J- ^ d 43. The size of this throttling effect can be given by H. can be changed with the aid of the throttle screw 48, namely via this throttle point pressure medium can flow out of the pressure chamber 37 via the bores 47 and 49 to the unpressurized bore 43. Depending on the flow cross-section of the cross-section given by the throttle body 48, the throttling effect by the stepped piston 33 can be varied, and thus the damping pressure in the chamber 22. This design achieves damping for constant deceleration of the piston 15. This delay can, however, be influenced by the throttle body 48. The channel 46 to the end part ^L

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the bore step 32 ', represents a throttle part through which the stepped piston 33 reaches its left position in a damped manner, as a result of which it is prevented from rattling.

If the notches ^Λ ^ 1χι are brought to its other working position, then dei bore 43 pressure medium is supplied via a control valve, not shown. As a result, the stepped piston 33 is immediately pushed into its right end position, and pressure medium can now pass unhindered from the bore 43 to the bore 35 ′ and via ¹ the line 29 into the tree 22. The piston 15 is now shifted to the right, with exactly the same process being repeated on valve 52.

After the throttle bore 25 has been passed by the piston 15 Now, of course, pressure medium can also again reach the pressure space 37 from the space 22 - in which there is now high pressure. However, this pressure also prevails on the other end faces of the stepped piston, so that it is hydraulically balanced and the spring pushes it into its right end position. The pressure medium losses over the throttle bores 19 ″ and 25 are negligible small.

Of course, a damping device described above can also be provided only on one side of the working cylinder, if on its other side no damping is necessary. The valves 31 »52 can be attached directly to flange surfaces of the working cylinder s attached to it, or at any point away from it. That depends on the most appropriate Points of view. So it is by no means the case that the connections must look as shown in FIG. 1, namely with welded-on connecting pieces 24, 27, 21 single-acting cylinder is only a damping device anyway necessary on one side.

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The valve according to the exemplary embodiment in FIG. 2 is denoted by 53 and largely corresponds to the valve 31 according to the exemplary embodiment of Fig. 1. The main difference is

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in that the throttle body 48 and the associated bores are omitted. Another difference "consists in the fact that the stepped piston - it is designated by ^ A - is guided with its piston part 54 'of small diameter with play in part 55' of a stepped bore 55 "Guided. Thus" there is a throttle gap 56 from a space 5S in the end part at the stepped bore 55 to the taurn 57 at the small step of the piston. A spring 59 is arranged in the bar 58 of the end part. Three bores 60, 61, 62 open into the stepped bore. The line 29 leads to the bore 60, the conduit 30 leads to the bore 61 and the conduit 44 leads to the bore 62. The damping of the stepped piston 5 ^ takes place here Throttle gap 56. The throttle point for damping the movement of the piston ^ 5 is formed at the "transition from the bore 60 to the stepped bore 55 through the shoulder of the stepped piston. In the embodiment according to FIG. 1, this throttle point is at the transition from the bore 43 into the stepped bore 32.

In the embodiment according to FIG. 2, the damping pressure for the movement of the piston 15 ″ builds up in front of the stepped piston 54 in the bore 60. The stepped piston is thereby not acted upon with the damping pressure for damping the piston 15, so that only the hydraulic force from the pressure in the working chamber 18 acts on the stepped piston, and over again the bores 25, 26, the line 30 and the bore 61. The spring 59 acts against this force Throttle cross-section at 55 »60, which has the consequence that the pressure to dampen the piston 15 and thus its deceleration Remove via the damping path. Otherwise the function is the same as described above.

The exemplary embodiment according to FIG. 3 is a combination of the exemplary embodiments according to FIGS. 1 and 2. The same parts as in the exemplary embodiment in FIG. 2 are denoted by the same numerals. The stage 5 ^ 'of the Stufeiikoibens ^ A is in turn out with play in the end part 55' äer stepped bore 55, so that .between

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your space 47 and the end part 58 of the bore a throttle el gap 56 is formed, which in turn for damping the stepped piston serves. The throttle point for damping the piston 15 is again formed at the entry of the bore 60 to the seam 57. Of the Bore 62 now runs a channel 63 to the pressure chamber 64 on the large piston stage. This channel is through the throttle body 48 controlled. Again, the function is largely the same As before, however, the damping pressure can be varied again by means of the throttle body 48.

The exemplary embodiment according to FIG. 4 shows a modification of the valve 3 ^ according to Fig. 1. It bears the designation 65, is closed by a cover 66 and has a non-continuous longitudinal bore 67 · In the longitudinal guide 67 is a Slide 68, of the two collars 69 and 70, is guided so that it can slide tightly. owns. Between these bands there is a part 71 smaller diameter. On the one hand, the slide 70 has an extension 72-.iD.it with which it is arranged in the bore 67 Spring 73 is pressed against cover 66. The pressure space on the extension 72 is denoted by 74-, the space on the spring 73 with 75 * The space on the piston part with a reduced diameter 71 bears the designation 76. A bore opens into this 77, to which the line 29 is brought. A bore 78 opens into the pressure chamber 74, to which the line 30 leads. Furthermore, a bore opens into the pressure chamber 76 79, to which the line 44 is connected, which leads to a control valve or to the container 45. Of the Bore 79 leads a channel 80 to the pressure chamber 75 · The channel 80 is also connected to the pressure chamber 76 via the throttle bore 82 tied together. Through the throttle body 81, the pressure in the pressure roughness 75 can be changed and thereby the compressive force on the left face of the stepped piston. In contrast to the exemplary embodiment according to FIG. 1, in which the pressure on the right side of the stepped piston in space 37 has been changed, now the The pressure prevailing in the pressure room 75 is changed by the throttle body 81. If the slide 70 moves due to increasing pressure in the Pressure chamber 74- "at the beginning of the damping process to the left, so

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he again throttles the connection between the bores 77 and 79 · The throttle bore 82 serves as an additional locking screw for the damping, don't just use the slider anymore 70 the connection from the holes 77? 79 is throttled.

In all exemplary embodiments, it is possible to change the preload of the springs loading the control slide by means of screws or similar known gowns. Thereby, the damping v.'irkung also varies v / ground, in which case the throttle body 48 in Fig. ^Λ and Fig. 3, sov / ie the Di osselkörper 8 ^ in Fig. 4 may be omitted with the corresponding connection channels. Such an embodiment is shown in FIG.

The damping \ alve ^r is designated by 83, has a continuous stepped bore 84 in which a stepped piston is guided slidably tight 85th The housing 83 ′ is closed by a cover 86. Two bores 87, 88 which are connected to lines 29, 30 and 50, respectively, open into the step with a large diameter. A channel 90 leads from an outlet bore 89 to the rear part 91 of the stepped bore. In this a screw 92 is arranged, with which the preload of a spring 93 loading the stepped piston can be changed. The function can be easily explained using the above examples.

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Claims (8)

E. 1 4 3 B Ao Expectations . ! Device for damping the movement of the piston of a working cylinder ar. Lnce des Eubv-egs with the help of the extension room associated throttle, which is located in a passage to a pressureless Eaum, characterized in that the device essentially from a specially provided Component (3 ^, 53, 65) is made directly to the working cylinder (10) is attachable or can be arranged separately from this, and that a piston valve in this component (33, 54, 68) is arranged, which controls the passage (35, 43; 60, 62; 7 ^, 79). 2. Apparatus according to claim ", characterized in that the Piston slide is subjected on the one hand to the pressure in the extension space (for example 22) and the force of a spring (42, 59, 73) on the other hand from the pressure in the working space (for example ^ 8) of the working cylinder is acted upon, which pressure is applied to the piston valve via a pressure formed in the wall of the working cylinder Bore ("9> 2") is fed to the piston ("5) when approaching is controlled in its end position. 3. Device according to claim "and / or 2, characterized in that that that pressure chamber (37) on the piston valve (33) 1 in which the pressure of the working chamber ("8) prevails, via a second one Throttle (48) is relieved to a pressureless space (45). 409847/01 54 -11- B. 1 * 3 6 4. Apparatus according to claim 2, characterized in that? the Pressure chamber (75) in which the spring (73) is arranged, via a adjustable throttle (8 ") is connected to the pressureless Eaum. 5. Device according to one of claims 1 to 4, characterized in that that the holes ("9, 2") in the wall of the working c ¹ : c
The cylinder unc ^ Sdhrung (82) in the valve (65) are designed as throttle bores. 6. Device according to one of claims Ί to 5? characterized in that the piston slide (33) is designed as a differential piston and that its large end face ^{is acted upon by the pressure in the working chamber ("1} S) of the working cylinder, its king surface by the pressure in the ejection chamber (22). 7. Device according to one of claims "to 6, characterized in that the working cylinder is double-acting and that ö ^{e <} 3 cylinder side associated with a damping device i st. 8. Device according to one of claims ^Λ to 7> characterized in that there are two inlet bores (3'S 35) in the component (3 "% 53, 65), which with two bores (23, 26) in the working cylinder - possibly via lines (29, 30) are connected, one of which is at the end of the working space, the other is at a distance from this which is greater than the width of the piston. 409847/0154 - 12 - - ΛΖ - E. 1 4 3 8 9 · "Device according to one of claims ^Λ " to S, characterized in that the preload of the spring loading the ICol "over" can be changed. 409847/0154