WO2007012471A1

WO2007012471A1 - Actuating cylinder

Info

Publication number: WO2007012471A1
Application number: PCT/EP2006/007357
Authority: WO
Inventors: Michael Ruopp; Christian Schweigl
Original assignee: Gustav Magenwirth Gmbh & Co. Kg
Priority date: 2005-07-26
Filing date: 2006-07-26
Publication date: 2007-02-01
Also published as: ES2443893T3; DE102005036124A1; EP1907708A1; EP1907708B1

Abstract

In order to improve an actuating cylinder, comprising a cylinder housing having an interior space which is enclosed by the latter, a piston which is arranged in the interior space and is guided in a guide direction by at least one running face of the cylinder housing and delimits a pressure space in the cylinder housing with a piston head, and comprising a sealing element which is held on the piston and is arranged so as to surround the latter in order to seal the pressure space between the piston and the cylinder housing, in such a way that the wear which occurs is as small as possible, it is proposed that the sealing element is part of a sliding element which comprises a guide element, that the guide element is guided movably in the guide direction by way of at least one guide face on a first running face of the cylinder housing, and that guide element guides the piston in a floating manner relative to the first running face.

Description

Betätigungszyiinder

The invention relates to an actuating cylinder, for example for drive or braking devices of vehicles, comprising a cylinder housing with an enclosed by this interior, a piston arranged in the interior, is guided in a guide direction by at least one running surface of the cylinder housing and a piston head with a pressure chamber limited in the cylinder housing, and held on the piston and arranged circumferentially around this sealing element for sealing the pressure space between the piston and the cylinder housing.

Such actuating cylinders are known from the prior art. In these, there is the problem that the piston experiences forces when operating the intended vehicle part, which act on the piston in the direction of a tilting movement.

This has the disadvantage that in this way the piston guided on the at least one running surface causes signs of wear either on the running surface or on the piston itself.

The invention is therefore based on the object to improve an actuating cylinder of the generic type such that the occurring wear is minimized.

This object is achieved according to the invention in an actuating cylinder of the type described above, that the sealing element is part of a sliding element comprising a guide element, that the guide element is guided movably in the guide direction with at least one guide surface on a first running surface of the cylinder housing and in that the guide element floatingly guides the piston relative to the first running surface.

The advantage of the solution according to the invention is the fact that with this the wear by friction of the piston is minimized at the first tread and thus a longer life of the actuating cylinder is achieved.

In this case, it is particularly favorable if the guide element guides the piston essentially without contact to the first running surface, so that thereby no wear on the running surface caused by the piston occurs.

A particularly expedient solution provides that there is a gap of at least 1/10 mm between the outside of the piston facing the first running surface and the first running surface with the piston centered.

As a result, a sufficiently large gap is created, which largely avoids contact between the running surface and the piston even with strong, the piston acting in the direction of tilting forces.

With regard to the arrangement of the sliding element relative to the piston so far no further details have been made. So it is particularly favorable to obtain a small volume of construction, when the sliding element is arranged in the region of the piston crown. Further, the type of arrangement of the slider on the piston has not been specified. A particularly simple and cost-effective solution with regard to the arrangement of the sliding element provides that the sliding element is arranged in a receptacle in the region of an outer side of the piston.

In this case, the fixation of the sliding element in the receptacle can be made arbitrarily. It is particularly simple in terms of design if the sliding element is held positively fixed in the receptacle.

Usually, the slider is made as an annular body made of an elastic material, which can thus be inserted through this in the circumferential direction in the recording and fixed in this form-fitting manner.

The type of fixation can also be done in different ways. It has proved to be expedient if the sliding element rests with a bearing surface on a contact surface of the receptacle and is thus supported in particular in the receptacle in the radial direction to a central axis.

In order to be able to sufficiently support the sliding element, in particular when the pressure chamber is pressurized, on the piston, it is preferably provided that the sliding element bears against a fulcrum surface of the receptacle with a foot surface running transversely to the guide direction. Such interaction of the foot surface with the flange surface creates the possibility of optimum support for joint movement of the sliding element and the piston in the guide direction. With regard to the arrangement of the sealing element relative to the guide element so far no details have been made. Thus, it would be conceivable in principle to arrange sealing element and guide element in a different order relative to the pressure chamber.

An advantageous solution provides that the sealing element is arranged on a pressure chamber facing side of the guide element.

With regard to the design of the guide element and the sealing element relative to each other so far no further details have been made. Thus, an advantageous embodiment provides that the sealing element and the guide element form an integral part, so that the guide element and the sealing element can be produced in a simple manner as a one-piece coherent part.

A favorable variant provides in this case that the guide element has a support body, from which starting the sealing element extends.

With regard to the formation of the density element, no further details have been given so far.

Thus, an advantageous embodiment provides that the sealing element has an outer sealing lip and an inner sealing lip, which extend V-shaped to one another. Such a constructed sealing element is particularly suitable to achieve a tight seal between the piston and the cylinder housing, even at a high pressure in the pressure chamber. In particular, in the case of a guide element with a support body, it has proved expedient if the sealing lips extend from the support body.

Furthermore, it is provided in such an arrangement of the sealing lips, that the sealing lips are arranged on a side opposite the foot surface side of the support body.

Preferably, the sealing lips are formed so that the outer sealing lip rests with a sealing lip edge on the first tread.

Furthermore, it is preferably provided that the inner sealing lip rests with a sealing lip edge on a contact surface of the piston.

With regard to the arrangement of the at least one guide surface so far no further details have been made. Thus, an expedient solution provides that the at least one guide surface is arranged on a side of the sealing element which is opposite to the pressure chamber, thereby resulting in a particularly compact construction of the sliding element.

Furthermore, it is favorable if the at least one guide surface is arranged in the region of the support body.

Particularly favorable is a solution in which the at least one guide surface is arranged on an elastically deformable region of the support body, so that it is possible to obtain a contact force in the region of the guide surface by deformation of the support body during installation of the guide element.

The provision of an elastic, acting on the at least one guide surface contact pressure has the advantage that so that the guide surface can be used not only for guiding the piston, but also at the same time in addition to the seal, in particular for sealing against partially resulting in the pressure chamber vacuum at a sealing element with sealing lips can only be controlled by structurally complex measures.

In particular, it is advantageous if the force acting on the guide surface pressing force approximately transverse to the guide surface and approximately transverse to the tread is effective.

With regard to the realization of the guide surface on the guide element no further details have been made in connection with the embodiments described so far.

Thus, an advantageous embodiment provides that the at least one guide surface is arranged on a guide bead of the guide element and thus projects beyond the usual contour of the guide element.

It is particularly advantageous if the guide bead is seated on the support body.

A particularly favorable arrangement of the guide bead provides that it adjoins a foot surface of the support body. For example, while the guide bead in the direction of a height H of the sliding element have a small extent.

However, a solution which is advantageous for the supporting effect provides that the guide bead has an extension in the direction of the height H of the sliding element which corresponds to at least one fifth of the extension of the supporting body in the direction of the height H.

In order not to let the guide bead be too large, however, it is favorable if the guide bead extends in the direction of the height H of the sliding element over a maximum of half the extent of the support body in the direction of the height H.

In particular, the provision of a guide bead with one or more of the features described above has the advantage that thus a sufficiently large radially acting force acts on the support body and the support body in the region of a bearing surface of the sliding element to a corresponding contact surface of the recording applies, so that a tilting movement the entire sliding element can be largely avoided around an axis perpendicular to the cross-sectional area.

In order to obtain the leadership qualities, in another embodiment! provided that the guide element not only has a guide surface, but a plurality of guide surfaces.

In such a plurality of guide surfaces is expediently provided that each of the guide surfaces is arranged on a guide bead.

Furthermore, it is favorable for a plurality of guide surfaces, if some of the plurality of guide surfaces have a different radial extent.

An expedient solution provides that the guide surface with the greatest radial extent is arranged next to the pressure chamber and that at least one further guide surface with a smaller radial extent is arranged on a side of the first guide surface opposite the pressure chamber.

Furthermore, it is favorable in the case of a plurality of guide surfaces if depressions are arranged between guide surfaces which follow one another in the guide direction.

The provision of the recesses has the advantage that in these can collect lubricant, which also serve to ensure the best possible lubrication and thus ease of movement of the guide element relative to the tread in the region of the guide surfaces.

Such wells could be local. It is particularly favorable, however, if the depressions are formed annularly encircling and thus preferably form recessed grooves.

With regard to the training and in particular dimensioning of the sliding element so far no further details have been made. Thus, it is preferably provided for the dimensioning of the inclusion of the sliding member in the piston that the ratio of an inner diameter of the receptacle to the outer diameter of the piston is greater than about 0.7, more preferably greater than about 0.8.

Furthermore, no details were given as regards the height of the sliding element, that is to say the extent of the sliding element in the guiding direction.

An advantageous solution provides that with an outer diameter of the piston of at least 20 mm, the height of the sliding element in the range of about 1.5 to about 4.5 mm, more preferably in the range of about 2 mm to about 3.5 mm. Preferably, a value for the height of the slider is between about 2.5 mm and about 3 mm.

Furthermore, it is preferably provided that the ratio of an outer diameter of the piston to the height of the sliding element is greater than approximately 8, more preferably greater than approximately 10.

With regard to the height and the width of the sliding element so far no details have been made.

In particular, it is favorable if, in the installed state of the sliding element, the width B thereof is greater than half the height H.

It is even better if the width B of the sliding element is greater than about 0.8 times the height H. Further, it is preferably provided that in the installed state of the sliding element, the height H of the slider is less than about l, 3 times the width B, it is even better if the height H is less than about l, 2 times, even better the l , l times the width B.

With regard to an advantageous guidance of the piston by means of the sliding element according to the invention, it is preferably provided that the sliding element with more than about 50% of its extension in height serves to guide the piston.

With regard to the design of the slider itself no further details were made. Thus, it is also provided that an outer sealing lip has a lower height than an inner sealing lip in order to improve the sealing effect.

With regard to the leadership of the piston on the cylinder housing so far no further information has been made. In principle, it would be conceivable to guide the piston only in the region of the piston crown on the cylinder housing.

However, a particularly favorable solution with regard to a tilting movement of the piston provides that the cylinder housing has a second running surface which is arranged at a distance from the first running surface in the guide direction.

A particularly advantageous solution provides that the second running surface is arranged in the interior of the cylinder housing. Furthermore, no details were given regarding the guidance of the piston on the second tread. Thus, a particularly preferred embodiment provides that the piston is guided on the second running surface with a guide head extending from the piston head.

For an additional guidance of the piston can be realized, which improves its leadership characteristics with respect to the tilting.

For reasons of the lowest possible construction volume, it is expedient if the second running surface has the same or a smaller diameter than the first running surface.

Furthermore, it is favorable for reasons of simplicity, when the guide head of the piston is guided directly on the second running surface, since no sealing must be made on the second running surface and thus a wear between the guide head and the second running surface for the life of the actuating cylinder is subordinate.

In order to obtain a defined position of the piston even in the unpressurized state, it is preferably provided that the piston is acted upon by a resilient force accumulator arranged in the cylinder housing in the direction of an extended end position with a maximum pressure chamber.

In order to further obtain optimum power transmission to the element to be actuated, provision is expediently made for the piston to be provided with a pressure-transmitting element. In a preferred solution, the pressure-transmitting element is a component with a spherical shape, which is preferably punctually acted upon by the piston.

Another advantageous solution provides that the pressure transmission element is a component which can be acted upon by the piston surface.

Such a pressure transmission element is favorably a ball, which rests substantially punctiform on the element to be actuated and thus also largely reduces the transmission of tilting moments on the piston.

Further features and advantages of the invention are the subject of the following description and the drawings of an embodiment.

In the drawing show:

1 shows a section through an embodiment of an actuating cylinder according to the invention.

Fig. 2 is a fragmentary enlarged view of a range

A in Fig. 1;

Fig. 3 is an enlarged view of a first embodiment of a sliding element according to the invention in not built and thus not acted upon by the elements of the actuating cylinder state and

Fig. 4 is an enlarged view similar to Fig. 3 of a second

Embodiment of a sliding element according to the invention in the non-installed state.

An illustrated in Fig. 1 embodiment of a hydraulic cylinder 10 according to the invention comprises a cylinder housing 12 which encloses an inner space 14 in which a designated as a whole by 16 piston is arranged, which is movable relative to the cylinder housing 12 in a guide direction 18.

The piston 16 comprises a piston head 20, which extends transversely to the guide direction 18 in the direction of a central axis 24 of the cylinder housing 12 cylindrical first tread 22 of the cylinder housing 12, which encloses a first, piston bottom side portion 14 a of the interior 14.

The piston head 20 is arranged and dimensioned so that a maximum radius to the central axis 24 extending outside 26 of the piston head 20 usually does not touch the tread 22, but between this outer side 26 and the tread 22, a gap 28 remains, which at Central axis 24 centered arrangement of the piston crown 20 is at least 5/100 mm. That is, the outer side 26 has a maximum diameter that is at least 1/10 mm smaller than an inner diameter of the tread 22. The piston head 20 comprises a receptacle 32, which is arranged in the region of the outside 26 and circumscribes in the form of a depression, in which a first embodiment of a sliding element 30 is arranged, which comprises a guide element 34 on the one hand and a sealing element 36 on the other hand, the sealing element 36 having one within the Inner space 14 existing pressure chamber 40 seals in the area between the tread 22 and the piston head 20, while the guide member 34, the piston head 20 on the running surfaces 22 floating and substantially non-contact and in the guide direction 18 slidably.

On the piston head 20, a guide extension 42 is formed on a side facing the interior 14, which extends into the interior 14 of the cylinder housing 12 starting from the piston head 20 and forms a guide head 44, which in turn provided with the guide head 44 alignment surfaces 46 at a second Running surface 52, formed in the cylinder housing 12 is guided, wherein the second running surface 52 encloses a second, inner portion 14b of the inner space 14.

In the simplest case, the alignment surfaces 46 slide directly on the second tread 52. However, it is also possible for the guide head 44 by means of a

Slider 30 corresponding sliding element on the second tread 52 to lead.

Overall, therefore, the piston 16 is guided in duplicate, namely on the one hand with the guide member 34 on the first tread 22 in the region of a first guide plane 56 and at a distance from the first guide plane 56 by means of sliding guide surfaces on the second running surfaces 44 aligning surfaces 46 in one second management level 58, on a the Pressure chamber 40 facing side of the first guide plane 56 and approximately parallel to this extends at a distance, so that overall results in a stable, substantially tilt-free guidance of the piston 16 in the cylinder housing 12.

The stable tilt-free guidance of the piston 16 is also given in an arrangement of the guide head 44 on a side facing away from the pressure chamber 40.

To pressurize the piston 16 leads into the interior 14 a

Feed channel 60, which preferably opens into the second portion 14b and via which the interior 14, a medium, in particular hydraulic medium, can be fed, which acts in the event of pressurization of the piston 16.

Further, between the supply channel 60 and the first portion 14a of the inner space 14, a connecting channel 62 is provided, via which directly from the supply channel 60 pressurized medium in the first portion 14a of the inner space 14 can be introduced.

In order to keep the piston 16 in a defined position in the pressureless state of the pressure chamber 40, for example, as shown in Fig. 1, in the guide head 44, a recess 62 is provided, in which an elastic force accumulator 64, for example in the form of a spring sits , which on the one hand on the piston 16 and on the other hand on the cylinder housing 12, for example in an end region of the supply channel 60, is supported.

But it is also conceivable to provide an acting on the piston head 20 elastic energy storage.

This elastic force accumulator 64 acts on the piston 16 in such a way that, in the state not acted upon by the medium, it always moves into its position corresponding to a maximum volume of the pressure chamber 40.

For applying an actuating shaft, for example an actuating shaft of a clutch, a dome-shaped receptacle 66 for a pressure element 68 is provided in the piston head 20, with which then the actuating shaft is directly acted upon. Preferably, the receptacle 66 is provided with a contact surface 67, which is set back relative to the first guide plane 56 and on an opposite side of the actuating shaft, resulting in an advantageous "pulling action" results on the pressure element 68, which has the consequence that the piston 16 does not buckle laterally.

For example, if the pressure element 68 is formed as a ball, the pressure element 68 acts substantially point-like on the contact surface 67 and substantially point-shaped on the actuating shaft in order to move them also in the guide direction 18 can.

However, it is also conceivable to provide a surface contact of the pressure element 68 on the contact surface 67, wherein the pressure element 68 could be formed, for example, cylindrically with flat end faces.

Preferably, in the illustrated solution, the second running surface 52 is formed such that, although it is arranged coaxially with the first running surface 22, it has a diameter which is appreciably smaller than the first running surface 22 having. Thus, the piston 16 experiences a sufficient guidance in the guide direction 18, wherein the piston head 20 or the guide head 44 relative to the first tread 22 and the second tread 52 can move substantially without jamming in the guide direction 18.

The guide ratio results from the diameter of the piston crown 20 and the distance between the guide planes 56 and 58.

As shown in FIGS. 2 and 3, the sliding element 30 comprises a support body 80 which rests with a transversely to the guide direction 18 extending foot surface 82 on a flange 84 of the receptacle 32 in the piston head 20, which is opposite to the outside 26 set back into the piston head 20th hineinerstreckt and in a radial contact surface 86 of the receptacle 32 in the piston head 20 passes. At this radial abutment surface 86, the support body 80 is supported with a bearing surface 88 radially to the central axis 24, wherein the ring-encircling support body 80 abuts against the radial abutment surface 86 by virtue of its own pretension in the circumferential direction with the bearing surface 88.

For example, a diameter DA of the radial abutment surface 86 of the receptacle 32 is more than 0.8 times an outer diameter DK of the piston head 20 on the outer side 26.

Further, the slider 30 has a height H (Fig. 2) ranging from about 1.5 mm to about 4.5 mm. Further, the ratio of the outer diameter DK to the height H is greater than about 10. In addition, as shown in Fig. 2 - in the installed state of the sliding member 30, a radial width B of a cross section of the sliding member is greater than or equal to half the height H, in particular greater than or equal to two thirds of the height H. Preferably, the height H is lower than that, about 1, 3 times the height H.

For example, on its side facing the support surface 88 and facing the first running surface 22, the support body 80 has three guide beads 92, 94, 96 arranged one above the other in the guide direction 18, for example the guide bead 92 closest to the pressure space 40 being the first Guide bead, which on a side opposite the pressure chamber 40 side of the first guide bead 92 arranged guide bead 94 of the second guide bead and on a first guide bead 92 opposite side of the second guide bead 94 arranged guide bead 96, the third guide bead.

Each of these guide beads 92, 94, 96 forms a radially outer guide surface 102, 104 and 106, with which the support body 80 rests against the first running surface 22 and is thereby guided on this. Overall, the voltage applied to the running surface 22 part of the sliding member 30, in particular of the guide beads 92, 94, 96 having part over more than 50% of the height H of the sliding member 30th

In the non-inserted state of the sliding element 30, the first guide surface 102 has the largest radius, for example, while the guide surfaces 104 and 106 have approximately the same smaller radii, for example exhibit. When inserted into the receptacle 32 in Kolbenbodeπ 20 sliding member 30, all guide surfaces 102, 104, 106 has a radius which is greater than the radius of the first tread 22.

If such a sliding member 30 is inserted into the receptacle 32 in the piston head 20 and is inserted with this in the cylinder housing 12, the sliding member 30 experiences in the region of the support body 80, a radial compression, which results in execution of the sliding member 30 of an elastically deformable material thereto in that, as a result of the action of the running surface 22 on the guide surfaces 102, 104 and 106, the entire support body 80 is compressed in the radial direction due to a press-fitting thereof between the running surface 22 on the one hand and the radial abutment surface 86 on the other hand.

This results in the support body 80, as shown in Fig. 3, a radially acting elastic force 108, on the one hand presses the support body 80 with the radial support surface 88 against the radial abutment surface 86 and on the other hand, the guide beads 92, 94 and 96 with their guide surfaces 102nd , 104 and 106 against the tread 22 presses.

Preferably, the radial deformation of the seated in the receptacle 32 in the piston head 20 supporting body 80 when inserted into the cylinder housing 12 about 0.1 mm to about 2 mm from the not inserted into the housing 12 state.

In addition, between the guide beads 92, 94 and 96 respectively opposite the guide surfaces 102, 104, 106 in the radially deformed state of the support body 80 set back recessed grooves 112 and 114 are provided, which, as shown in particular in Fig. 2, as Adjusters serve for the lubricant collecting between the guide surfaces 102, 104 and 106 and simultaneously cause lubrication in the area of the guide surfaces 102, 104 and 106 during the movement of the sliding element 30 in the guide direction 18.

Overall, therefore, the support body 80 forms with the guide beads 92, 94 and 96 and the seated on these guide surfaces 102, 104 and 106, the guide member 34, with which the floating guide of the piston head 20 and thus of the piston 16 in the first guide plane 56 to the first Running surfaces 22 such that the outer side 26 of the piston head 20, the first tread 22 is not substantially touched and consequently occurring in conventional hydraulic cylinders "shrinkage" of the tread 22 due to the mechanical wear can be avoided.

In addition, to improve the seal between the piston head 20 and the tread 22, the sealing element 36 is provided, which is integrally formed on the guide member 34 and an outer sealing lip 120 and an inner sealing lip 122 which are V-shaped to each other and in their foot areas 124 and 126 in the support body 80 go over.

In particular, the inner sealing lip 122 is higher in the direction of the height H than the outer sealing lip 120 in order to improve its sealing effect.

The inner sealing lip 122 and the outer sealing lip 120 thus lie on a pressure chamber 40 facing side of the support body 80 and extend in the non-applied state of the sliding ring 30 in the radial direction Central axis 24 on the one hand on the support surface 88 inwardly and on the guide surface 102 to the outside to form a gap 128 between the outer sealing lip 120 and the inner sealing lip 122nd

The sealing lips 120 and 122 are acted upon insertion of the sliding member 30 in the hydraulic cylinder 10 toward each other, so that the gap 128 decreases. When inserted into the hydraulic cylinder sliding member 30, the outer sealing lip 120 is located with a sealing edge 130 under radial elastic bias on the tread 22, while the inner sealing lip 122 abuts with an inner sealing edge 132 on the radial abutment surface 86 of the piston crown 20. Due to the deformation, a radial biasing force 138 is created in the sealing element 36 formed by the outer sealing lip 120 and the inner sealing lip 122, which tends to move the sealing lips 120 and 122 in opposite directions away from each other, thus, the sealing lips 120 and 122 with their sealing edges 130 and 132 on the tread 22 and the radial abutment surface 86 of the receptacle 32 in the piston head 20 to keep in abutment. When the pressure chamber 40 is pressurized with the medium, this also penetrates into the intermediate space 128 and leads to an increased pressing of the sealing edges 130 and 132 on the first running surface 22 or the contact surface 86.

The sliding element 30 now leads not only due to the sealing element 36 with the sealing lips 120 and 122 to a good seal between the piston head 20 and the cylinder housing 12, in particular its first tread 22, against a the pressure chamber 40 supplied medium under reliable

Preventing leakage between the piston head 20 and the cylinder housing 12, but at the same time improves the tightness against negative pressure conditions in the pressure chamber 40 or engine-side overpressure conditions in that the guide surfaces 102, 104 and 106 due the elastic radial biasing force 108 are held on the tread 22 and thus maintained a sealing effect between the guide surfaces 102, 104 and 106 and the tread 22 even with pressure drop in the pressure chamber 40 and reducing the sealing function of the sealing lips 120 and 122, which also admitted Negative pressure conditions in the pressure chamber 40 holds, so that the guide element 34 itself also still - at least in such permitted negative pressure states or engine-side overpressure conditions - assumes a sealing function.

In a second embodiment of a sliding element according to the invention 30 ', shown in Fig. 4, those elements which are identical to those of the first embodiment, provided with the same reference numerals, so that with respect to the description of the same fully content with reference to the comments on the first embodiment can be.

In contrast to the first embodiment, however, not a plurality of guide beads 92, 94, 96 provided on the support body 80, but a single guide bead 142, which bulges in direct connection to the foot surface 82 radially outward and forms a guide surface 152, which in the area maximum extent of the guide bead 142 is arranged in the radial direction.

The guide bead 142 extends in the direction of the height H of the sliding element 30 'over a portion of the support body 18, which is more than about one fifth of the extension of the support body 80 in the direction of height H and less than about half of the extension of Support body 80 in the direction of height H. Subsequent to the guide bead 142, a radially drawn-in region 154, which extends approximately to the foot region 124 of the outer sealing lip 120, then follows.

The advantage of the arranged on the bead 142 guide surface 152 is in principle the same, as shown in the first embodiment, however, the bead 142 in the second embodiment has an improved support effect by an improved loading of the support body 80 takes place radially inwardly, so that with its radial bearing surface 88 is held on the radial contact surface 86 of the piston head 20 in abutment and thus a tilting movement of the sliding member 30 'and in particular of the support body 80 is largely suppressed by a tilt axis extending perpendicular to the cross-sectional surface.

Thus, despite the minimal overall height of the sliding element 30 'according to the invention, an air entry into the pressure chamber 40 is avoided and at the same time the required oil-tightness is achieved.

In the second embodiment, in the installed state corresponding to Fig. 2, the height H is preferably less than 1, 2 times the width B. The width B is also preferably more than 0.8 times the height.

A preferred embodiment of the sliding member has values of width B to height H between about 0.9 and about 1.1.

Claims

PATE NTAN S CHECK

1. actuating cylinder comprising a cylinder housing (12) with an enclosed by this interior (14), one in the interior (14) arranged piston (16), which is guided in a guide direction by at least one tread (22) of the cylinder housing (12) , and with a piston head (20) delimiting a pressure chamber (40) in the cylinder housing (12), and a sealing element (36) held on the piston (16) and surrounding it for sealing the pressure chamber (40) between the piston (16 ) and the cylinder housing (12), it can be seen that the sealing element (36) is part of a sliding element (30) comprising a guide element (34), that the guide element (34) is provided with at least one guide surface (102, 104, 106, 152) is movably guided on a first running surface (22) of the cylinder housing (12) in the guide direction (18) and that the guide element (34) guides the piston (16) in a floating manner relative to the first running surface (22).

2. Actuating cylinder according to claim 1, characterized in that the guide element (34) the piston (16) substantially non-contact leads to the first tread (22).

3. Actuating cylinder according to claim 1 or 2, characterized in that between one of the first running surface (22) facing the outside (26) of the piston (16) and the first running surface (22) in the centered position of the piston (16) has a gap (28 ) of at least 1/10 mm.

4. Actuating cylinder according to one of the preceding claims, characterized in that the sliding element (30) in the region of the piston head (20) is arranged.

5. Actuating cylinder according to one of the preceding claims, characterized in that the sliding element (30) in a receptacle (32) in the region of an outer side (26) of the piston (16) is arranged.

6. actuating cylinder according to claim 5, characterized in that the sliding element (30) is held positively fixed in the receptacle (32).

7. Actuating cylinder according to one of claims 5 or 6, characterized in that the sliding element (30) with a bearing surface (88) against a contact surface (86) of the receptacle (32).

8. actuating cylinder according to claim 6 or 7, characterized in that the sliding element (30) with a transverse to the guide direction (18) extending foot surface (82) on a flange surface (84) of the receptacle (32).

9. actuating cylinder according to one of the preceding claims, characterized in that the sealing element (36) on a pressure chamber (40) facing side of the guide element (34) is arranged.

10. Actuating cylinder according to one of the preceding claims, characterized in that the sealing element (36) and the guide element (34) form an integral part.

11. Actuating cylinder according to claim 10, characterized in that the guide element (34) has a support body (80) from which, starting from the sealing element (36).

12. Actuating cylinder according to one of the preceding claims, characterized in that the sealing element (36) has an outer Dichtiippe (120) and an inner sealing lip (122) which extend V-shaped to each other.

13. Actuating cylinder according to claim 11 or 12, characterized in that extending the sealing lips (120, 122), starting from the support body (80).

14. Actuating cylinder according to one of claims 11 or 12, characterized in that the sealing lips (120, 122) on one of the foot surface (82) opposite side of the support body (80) is arranged.

15. Actuating cylinder according to one of claims 12 to 14, characterized in that the outer sealing lip (120) bears with a sealing lip edge (130) on the running surface (22).

16. Actuating cylinder according to one of claims 12 to 15, characterized in that the inner sealing lip (122) abuts with a sealing lip edge (132) on a contact surface (86) of the piston (16).

17. Betätiguπgszylinder according to any one of the preceding claims, characterized in that the at least one guide surface (102, 104, 106, 152) on a pressure chamber (40) opposite side of the sealing element (36) is arranged.

18. Actuating cylinder according to one of the preceding claims, characterized in that the at least one guide surface (102, 104, 106, 152) in the region of the support body (80) is arranged.

19. Actuating cylinder according to claim 16, characterized in that the at least one guide surface (102, 104, 106, 152) is arranged on an elastically deformable region of the support body (80).

20. Actuating cylinder according to one of the preceding claims, characterized in that the at least one guide surface (102, 104, 106, 152) on a guide bead (92, 94, 96, 142) of the guide element (34) is arranged.

21. Actuating cylinder according to claim 20, characterized in that the guide bead (92, 94, 96, 142) on the support body (80) sits.

22. Actuating cylinder according to claim 21, characterized in that the guide bead (142) adjoins a foot surface (82) of the support body (80).

23. Actuating cylinder according to one of the preceding claims, characterized in that the guide element (34) has a plurality of guide surfaces (102, 104, 106).

24. Actuating cylinder according to one of claims 17 to 23, characterized in that each of the guide surfaces on a guide bead (92, 94, 96) is arranged.

25. Actuating cylinder according to claim 23 or 24, characterized in that of the plurality of guide surfaces (102, 104, 106) have some different radial extent.

26. Actuating cylinder according to claim 25, characterized in that the guide surface (102) with the largest radial extension of the pressure chamber (40) is arranged next and the at least one further guide surface (104, 106) with a smaller radial extent on a the pressure chamber (40 ) opposite side of the first guide surface (102) is arranged.

27. Actuating cylinder according to one of claims 19 to 24, characterized in that between in the guide direction (18) successive guide surfaces (102, 104, 106) depressions (112, 114) are arranged.

28. Actuating cylinder according to claim 27, characterized in that the recesses (112, 114) are formed annularly circumferentially.

29. Actuating cylinder according to one of the preceding claims, characterized in that in the installed state of the sliding element (30), the width B thereof is greater than half the height H.

30. Actuating cylinder according to one of the preceding claims, characterized in that in the installed state of the sliding member (30), the height H of the sliding member (30) is smaller than that about l, 3 times the width B.

31. Actuating cylinder according to one of the preceding claims, characterized in that the cylinder housing (12) has a second running surface (52) which is arranged in the guide direction (18) at a distance from the first running surface (22).

32. Actuating cylinder according to claim 31, characterized in that the second running surface (52) in the interior (14) of the cylinder housing (12) is arranged.

33. Actuating cylinder according to claim 31 or 32, characterized in that the piston (16) is guided on the second running surface (52) with a piston head (20) extending from the guide head (44).

34. Actuating cylinder according to one of claims 31 to 33, characterized in that the second running surface (52) has the same or a smaller diameter than the first running surface (22).

35. Actuating cylinder according to claim 33 or 34, characterized in that the guide head (44) of the piston (10) is guided directly on the second running surface (52).

36. Actuating cylinder according to one of the preceding claims, characterized in that the piston (16) is acted upon by an in the cylinder housing (12) arranged elastic energy accumulator (64) in the direction of an extended end position with maximum pressure chamber (40).

37. Actuating cylinder according to one of the preceding claims, characterized in that the piston (16) is provided with a pressure-transmitting element (68).

38. Actuating cylinder according to claim 37, characterized in that the pressure-transmitting element (68) is a component with a spherical design and punctiform adhesion to the piston (16).

39. Actuating cylinder according to claim 37, characterized in that the pressure-transmitting element (68) is a component with areal configuration and surface frictional connection with the piston (16).