GB2239053A

GB2239053A - Motor of the oscillating-piston type

Info

Publication number: GB2239053A
Application number: GB9025072A
Authority: GB
Inventors: Kurt Stoll; Gerhard Thorwart
Original assignee: Festo SE and Co KG
Current assignee: Festo SE and Co KG
Priority date: 1989-12-14
Filing date: 1990-11-19
Publication date: 1991-06-19
Anticipated expiration: 2010-11-19
Also published as: DE3941255A1; GB2239053B; GB9025072D0; KR950009555B1; DE3943716C2; DE3941255C2; KR910012558A

Abstract

The motor has a housing 1 defining a piston space 2 which has a circular cross section. The pivot axis 4 of the pivoting piston 3 extends through the center of the piston space 2. A piston space divider 30 provides a sealing action at the inner wall surface 9 of the piston space 2 and cooperates with a mating seal 36 at a cylindrically curved sealing face 37 of the pivoting piston 3. It is in this manner that pivot angles of over 270 DEG are possible. The pivot angle is adjustable by means of a pair of adjustable stops (67, Fig. 3) and a cooperating abutment (58) mounted on an external portion of the motor shaft. Details of the mounting and construction of piston 3 and divider 30 and of seals associated therewith are given. <IMAGE>

Description

1 1 S i.

- 1 A Fluid Power Motor of the Vane Type The invention relates to a vane-type fluid power motor comprising a motor housing in which a piston space is arranged, in which a vane piston adapted to oscillate during operation is located, said piston being connected in a torque transmitting manner by means of a bearing member with an output member, more particularly in the form of a shaft, extending out of the piston space, and possessing a vane which substantially radially extends from. the bearing member and being adapted to cooperate with mating surfaces on the housing in a sealing manner so that the piston space is subdivided into two working spaces for driving fluid, said bearing member having a sealing surface which extends for at least sorne distance in the circumferential direction in relation to the axis of such oscillation in the form of the outer face of a circular cylinder, such sealing surface being adapted to engage a mating seal means on the housing when the motor is in operation.

Such vane-type motors are used when the output member, which is generally in the form of a shaft, is to be rotated and is more particularly to be rotated with changes in the direction of rotation. In the case of a design described in the Austrian patent 338,065 it is possible to cause angular motion to take place through an angle of up to 2700. For this purpose the motor includes a bearing part seal designed in the forn, of a slotted tubular member extending around the bearing part of the pivoting piston so that when the pivoting piston iE pivoted its. sealing 1 1 J surface runs on a mating seal, which is secured to the motor housing. The piston space containing the pivoting piston as seen in cross section perpendicular to the pivot axis has the form of a circular sector as subtended by the said pivot angle, such three-dimensional form of the piston being dictated by a corresponding shape of the wall of the housing. The latter involves a complex design of the motor housing and means that the costs of manufacture are increased. A further point to be considered is that the mating sealing part on the housing has to be replaced due to the wear and this takes time. Furthermore, there are no measures making possible adjustment or variation of the angle of pivot of the piston.

Accordingly one object of the invention is to devise a vane-type motor which, while being simple in structure, may be used for different ranges of pivot angle.

A further object of the invention is provide such a motor whose manufacture is more economic and which is simpler to assemble.

In order to achieve these or other objects appearing from the present specification, claims and drawings in the invention a vane- type fluid power motor comprising a motor housing in which a piston space is arranged, in which a vane piston adapted to oscillate during operation is located, said piston being connected in a torque transmitting manner by means of a bear-Ing merriber with an output member, more particularly in the form of a shaft, extending out of the piston space, and possessing a vane which substantially radially extends from the bearing member and being adapted to cooperate with mating surfaces on the housing in a sealing manner so that the piston space is subdivided into two working spaces for driving fluid, said bearing member having a scaling surface which extends for at least some distance in the circumferential direction in relation to the axis of such oscillation in the form of the outer face of a circular cylinder, such sealing surface being adapted to engage a mating seal means on 1 1 the housing when the motor is in operation, is characterized in that as seen looking in the direction of the pivot axis, the piston space has a circular cross section, and in that. a piston space divider is mounted in the piston space so as to make sealing contact with the inner wall surface of the piston space and having the mating seal thereon.

In this case the basic configuration of the piston space is particularly advantageous as regards the process of manufacture. The axis of pivot extends through the center of a piston space with an outline which is circular as seen in a cross section taken perpendicularly to the pivot axis. The radially measured distance between the pivot axis and the radially opposite portions of the internal surface of the piston space is practically constant over the entire circumference of the piston space. The vane piston and the piston space divider in accordance with the invention now both participate in the subdivision of the piston space into the two working spaces. It is not necessary to provide any parts of the motor housing for delimiting, in manner fixed in relation to the housing, the pivot space for the pivoting motion of the vane piston. The piston space. divider formed separately in the motor housina is able to be placed in the piston space after the manufacture of the housing without any trouble at all. Dependent on the maximum size. of the pivot angle which is desired, it is possible to selectively have a piston space divider with a larger or smaller extent in the circumferential direction in relation to the pivot axis. on the basis of a standard motor housing it is possible thus to have available different types of motor simply by the selection of the appropriate piston space divider. if the piston space divider has the function of a pivot angle limiting means, it is possible then by alternately using different pistons to set any desired maximum pivot angles.

Advantageous further features of the invention are described in the claims.

If the motor housing adjacent to the piston space is f 4 - divided into two axially consecutive housing parts, the assembly of the pivoting vane piston and of the piston space divider will be particularly simple.

The piston space divider is preferably in the form of a single insert, which is able to be uniformly handled. However, be this as it may, it is possible also for the piston space divider to have a multi-part structure and, as a convenient feature, for it to comprise at least one stiffening element, which endows it with the necessary structural stiffness as is required for the function it haE to perform. It may, for instance, consist of hard plastic material. In order to achieve optimum sealing performance on engagement with the adjacent inner surface of the piston space it is possible for the stiffening element to have an external space divider seal. Since the load it has to bear is purely static, it may consist of relatively soft material with satisfactory sealing properties. The space dividing seal U preferably molded onto the stiffening element. Furthermore it is possible for the mating seal, which is provided on the piston space divider to be formed by the space divider seal or by another additional seal. However, it is particularly advantageous if a part of the stiffening element is directly designed as a mating seal, this leading to very low, wear rates. Iii this case it is particularly advantageous howevel if the sealing surface cooperating with the mating seal, of the bearing part is provided on a bearing part seal made of a material which is softer than the material of the stiffening element.

In order to locate the piston space divider in the piston space it is convenient to provide at least one positive, interlocking connection, which is more particularly in the form of a plug connecting means. In the case of a motor housing subdivided at the piston space to form two axially adjacent housing parts it is an advantage if the piston space divider is able to be joined with each of such housing parts by means. of an interlocking connection, more particularly one which is detachable. Using the interlocking or positive connecting means it is possible to ensure M a simultaneous setting at the right angle and a fixation of the two housing parts in relation to each other, this facilitating assembly and avoiding faults therein.

In order to achieve a simpler way of varying the pivot angle of the piston it is possible for a setting means to be provided outside the piston space for adjustment thereof, and which acts between the output part and a part secured to the housing, more particularly in the form of the motor housing. in this case it is particularly advantageous that the pivoting piston and more particularly its pivoting vane is not directly acted upon by the setting device so that no damage is possible. Furthermore in case of need the pivot angle may be limited if the pivoting vane does not run against the piston space divider so that in this respect as well there is a prevention of damage.

The invention will now be described in detail with reference to the working embodiments shown in the accompanying drawings.

Figure 1 is a longitudinal section of a first design of the vane-type motor taken on the line 1-1 of ficrure 3.

Figure 2 is a cross section of the vane-tylle motor taken on the line HII of figure 1, the pivoting or vane piston and the piston space divider being shown unsectioned.

Figure 3 is a plan view looking in the direction of the arrow III towards the vane-type motor of figure 1.

Figure 4 shows a particularly advantageous working embodiment of a piston space divider as used in the working embodiment in accordance with figures 1 through 3.

Figure 5 shows the stiffening element of the piston space divider as in figure 4 without the space divider seal.

The preferred working embodiment of the pivoting vane motor in accordance with the invention has a motor housing 1 whose basic configuration is substantially circularly cylindrical. In the Interior thereof there Is a piston space 2, which is circumferentially enclosed and which contains a pivoting piston 3 adapted to pivot about an axis 4. The pivot axis 4 preferably coincides with the longitudinal axis of the motor housing 1. In the piston space 2 the motor housing 2 is divided into two axially consecutive housing parts 5 and 6. The respective parting plane 7 preferably extends at a right angle to the pivot axis 4 and through the piston space 2, preferably adjacent to the axial center of the latter. It will be clear that the housing parts may be stepped at the parting plane 7 for the purpose of locating them or the like (as indicated at 8).

As will be seen from figure 2, the piston space 2 has a circular cross section as seen looking in the direction of the pivot axis 4. The piston space 2 therefore has a circular outline with the pivot axis 4 extending through its center. In other words the piston space 2 subtends an angle of 3600 at the central pivot axis 4.

In the i.Torkiriq embodiment the inner surface e. facing the piston is llhe the circumferential face of a circular cyliride.-, the transitional zones between the circumferential surface 10 and the two base faces 11 and 11' being filleted. The longitudinal axis of the cylinder coincides with the pivot axis 4.

In the case of a working embodiment not illustrated here the circumferential surface 10 is curved outwards with an increased diameter of the piston space 2 so that the two base faces 11 and 111 are connected together at a section which is arcuate and is more particularly circularly arcuate.

The pivot axis 4 coincides with the longitudinal axis of a shaft-like output drive member 14, which extends through the piston 1 space 2 and extends out of the bottom and top of the motor housing 1 at opposite outer sides 15 and 16. In the vicinity of the passages 17 through the housing, on the one hand into the piston space 2 and on the other hand at the corresponding outer side 15 and 16 the output drive member 14 is preferably bearinged for rotary motion, as for instance by means of anti-friction bearings 18. The axial setting of the output drive member 14 is set at the outer side 15 by means of collar 19 on the shaft and on the opposite side by a retainer ring 191.

The output drive section 20, projecting out at the lower side 15, of the output drive member 14 is able to be connected in a torque transmitting manner with a part, not shown in detail, whichis to be oscillated by the motor. The end section 21 projecting out at the opposite end is used in connection with an adjusting means which is to be explained later. If there is no such adjusting means it is possible for the output drive membe, 16 to end within the motor housing 1.

The pivoting piston 3 has a bearing part 22. In the present working embodiment is preferably in the form of a hollow cylindrical bearing bushing 213". At the inner periphery it iE provided with interlocking means, which engage i.,yith corresponding interlocking means on the output drive member 14, on which the bearing part 22 is mounted in a torque transmitting manner. The interlocking means are in the present working erithodiment in the form of teeth. Since the bearing part 22 is preferably able to be axially moved on the output drive part 14, the pivoting piston 3 will during assembly automatically become aligned with the piston space 2 and the output drive member 14.

The pivoting piston 3 furthermore comprises a pivoting vane 25 which is preferably made integrally with the bearing part 22 and projects from the latter substantially radially in relation to the axis 4 towards the circumferential surface 10.

Conjointly with a piston space divider 30, which is yet to be explained, the pivoting piston 3 divides the piston space 2 into two working spaces 31 and, respectively, 32 with different volumes. A connection port 33 opens into each working space 31 and 32 for the supply and the removal of a fluid, more particularly compressed air, in order to cause the pivoting piston 3 to perform an oscillating movement about the pivot axis 4. This movement is transmitted by the interlocking engagement to the output drive part 14.

When this pivoting motion is in progress the piston seal 29 on the pivoting piston 3 runs over the inner surface 9. Said piston seal 29 preferably comprises a vane section 34 extending around the pivoting vane 25 and a bushing part 35 (which is preferably formed integrally with the vane 3 section 34, extends in the circumferential direction of the bearing bushing 23 and is more particularly annular in shape) on the two axial end parts of the bearing bushing 23. One respective bushing section 35 cooperates in the circumferential part of the output drive part 14 in a sealing manner with the associated base face 11 and, respectively, 11'. The vane section 34 occupies the vane edge directed in the axial and radial direction and provides a sea'ling action between the pivoting vane 25 and the inner surface 9. The presence of the buFhina sections leads to the useful advantage that no r-el)arate shaft seals are needed adjacent to the passage., 17 through the housinQ.

Wher, the pivoting piston 3 is in place the piston sps-ce constitutes an annular space, into which the pivoting vane 25, extends with engagement of different parts of its periphery in accordance with the position in which it is in. The above-mentioned piston space divider is arranged at a further circumferential position in the piston space 2. It is in this manner that the said annular space is subdivided into the two working spaces 31 and, respectively, 32. On the inner side of the piston space divider 30 which in the assembled state faces the bearing part 22, there is a mating seal 36, which during operation cooperates with a sealing surface 37 (formed on the bearing part 22) running past it in order to provide a sealing action in the part between the piston space divider 30 and the pivoting piston.

And, in relation to the pivot axis 4, this sealing surface 017 is on the radially outwardly directed circumferential part of the bearing part 22 and extends some distance in the circumferential direction, it having a curvature like that of the outer circumferential surface of a circular cylinder. It may for instance be constituted by the circumferential section of the bearing bushing 23 and as in the present working embodiment of the invention it is preferably provided on the surface of a bearing part seal 38, which more or less coaxially surrounds the bearing bushing 23 at the circumferential face thereof.

it is preferred for the bearing part seal 38 and the piston seal 29 to be fashioned integrally with each other, the two bushing sections 35 being able to constitute the end axial sections of the bearing part seal 38 if this should be desired. The entire seal configuration may be injection cast or molded an the pivoting piston 3 as a single unit, if this should be desired and as part of a further advantageous feature of the present invention it is possible for the other piston parts, which have so far not been mentioned, to be surrounded by such a sealing arrangement. However it is prefrerred for the through bushing opening and the end faces of the bearing bushing to be excepted.

The piston space divider 30 preferably comprises a single insert, which is detachably and replaceably arranged in the piston space. 2. It is in this respect a question of a preferably wedge-like component.

In order to provide for a hermetic separation of the two working spaces 31 and 32 the piston space divider 30 is furthermore in sealing engagement with the inner face 9 of the motor piston space 2. For this purpose it is provided circumferentially - in the zones which are radial and axial in relation to the axis 4, with the exception o of the part of the mating seal 36 - with a space dividing seal 39. In the illustrated working embodiment it i makes sealing contact both with the base faces 11 and 111 and also with the circumferential surface 10. The material of the space dividing seal is preferably soft and elastic so that, in view of the static sealing function, it ensures an excellent action even after long periods of use.

In order nevertheless to ensure that the piston space divider 30 is able to withstand high pressures there is internally a stiffening element 40, which is shown separate ly in f igure 5.

owing to its particular design and/or its material this element 40 ensures a high degree of strength and stiffness. The space dividing seal 39 is arranged adjacent to the outer side of this stiffening element 40 and surrounds same, as may for instance be seen from figure 4. In the case of the preferred working embodiment as illustrated the stiffening element 40 is, with the exception of the part adjacent to the mating seal 36 and interlocking parts 44, which are yet to be explained, entirely encased by elastomeric material, which at the respective parts forms the space dividing seal 39. owing to a ribbed surface structure as will be seen from figure 5 on the stiffening element 40 with numerous depressions 45 and rib-like projections 46 there is an intimate interlocking connection between the outer, softer scaling material and the inner harder material of the stiffening eleutent 40.

A further factor improving the sealing efficiency is the provision of at least one sealing lip 47 on the. space dividing seal 39, such lip extending around the stiffening element 40 in the part between the two end parts 48, directed towards the pivot axis 4, in the contact zone with the inner surface 9. In the illustrated working embodiment three such sealing lips 47 are provided, of which two are located in the marginal part, pointing in the pivot direction 49, of the piston space divider 30, whereas the third one is arranged between same.

owing to the dynamic sealing contact it is an advantage if the mating seal 36 is relatively hard. It may be in the form of 1 separate component arranged on the piston space divider 30. in the preferred embodiment of the invention it is however constituted by a part 50 of the stiffening element 40, which at the respective position is left uncovered and more particularly is without any space divider seal. On looking towards the mating seal 36 the reader will be able to see the part 50 encased by sections of the elastic casing.

As part of a further advantageous feature of the present invention guaranteeing better stability the breadth, as measured in the circumferential direction in relation to pivot axis 4, of the piston space divider 30 is designed to widen in a radially outward direction so that it appears like a slice of cake. The associated stiffening element 40 in this case will conveniently have a support rib 51 extending in the radial direction and on which projections 46 are molded extending in the pivot direction and having a height increasing in a radially outward direction starting from the part 50.

In order to endow the piston space divider 30 with a firm support in the pivot direction 49, it is positively connected with the housing wall delimiting the piston space 2. In the present. case there is a separate interlocking connection for each of the housing parts 5 and 6, this facilitating the assembly thereof, because they are then only able to he fitted together in a particular setting thereof. After fitting together the housing parts 5 and 6 may then be firmly joined together using, for instance, a row of screws 53 distributed along the periphery of the piston space 2.

A plug connection, that is to say, one with male and female parts is preferably used as an interlocking joining means. In the illustrated working embodiment this is in fact the case, wherein in the two base faces 11 and 11' of the piston space 2 at opposite points two depressions are provided which act as first interlocking parts 5,4. The interlocking parts 54 of any set of interfittling parts are spaced from each other in the radial direction in A relation to the pivot axis 4. Accordingly at the two axial sides 59, which are adjacent to each other in the assembled state, of the piston space divider 30, there are corresponding second or male parts 44 in the form, more particularly, of pin-like projections. These second joint parts 44 are preferably integral components of the stiffening element 40 and therefore very robust. As already mentioned and as is readily apparent from figure 4, they project past the elastic easing or space dividing seal 39. And as will be seen from figure 1 the first and second interlocking parts 54 and 44 fit into each other in the assembled state and make their contribution to the location of the piston space divider 30 in relation to the motor housing 1.

Owing to the detachable connection the piston space divider 30 may be quickly replaced if worn. Furthermore It would also be possible to use piston space dividers 30 whose breadth dimensions in the direction of pivoting are different in order, by fitting them, to provide vane-type motors with different maximum pivot angles. The connection ports 0.3 preferably open in the direct vicinity of the piston space divider 30 through the housing wall into one of the respective working spaces 31 and 32.

The piston space divider 30 may also be. used as a limiting element for the pivot stroke of the pivoting piston 3. Then at the end of the stroke the pivoting vane 25 will run on the piston space divider 30. Variations in the size of the pivot stroke may in this case be achieved by the selective use of piston space dividers 30 with a different size in the pivot direction. Furthermore in order to free the pivoting piston 3 of such mechanical effects completely and thus to increase the working life of the pivoting piston motor, it is however more expedient to provide a means 55, placed outside the piston space 2, in order to set the pivot angle and which operates between the output drive member 14 and a part integral with the housing. This adjustment means 55 offers the advantage that there is a large range of adjustment so that it is possible to take into account the large possible pivot angles of the. pivoting z piston motor in accordance with the invention in an optimum manner. In this case pivot angles of even over 2700 are possible. Nevertheless, it would also be possible for the adjusting means 55 to be used in other pivoting vane motors of different design, as for instance those in accordance with the prior art.

A radially projecting pivoting abutment 56 is arranged in a torque transmitting manner on the end part 21, which extends out of the motor housing 1, of the output drive part 14. It may be designed like the pivoting piston 3 and have a bearing bushing 57 mounted on the output drive member 14, there being a pivoting lever 58 (figure 3) which radially extends from the bushing 57 like a vane. At least one mating abutment 62 and 621 (which is fixed in relation to the housing) extends into the path of motion of the pivoting lever and it is able to be reset in relation to the pivot axis 4 in the circumferential direction. The mating abutments 62 and 62' are mounted and run on a circular, arcuate guide 63, which is centered on the pivot axis 4. Preferably this guide 63 extends for an angle of 3601> about its center of curvature.

The circularly curved guide 63 is in the. present working embodiment of the invention constituted by a circular groove 64 or recess let into the motor housing 1 from the tel) face thereof. The mating abutments 62 and 621 are slidingly mounted in the recess 64 by means of, more particularly, clamping elements 66 comprising. screws so that sliding motion in the longitudinal direction of the ring is possible and they may be arrested when required at any desired point. In the illustrated working embodiment theif-, is one mating abutment 62 and 621 for each of the two possible directions of pivoting, such mating abutment being able to be set at any desired point along the circumference about. the pivot axis 4.

A further preferred feature of the invention is such that the clamping elements 66 are used for coarse adjustment, whereas for fine adjustment there is in addition a fine adjustment element 67 extending into the path of pivot of the pivoting lever 56. Such fine adjustment element may more particularly a setting screw running in a threaded hole and which may be locked in its setting by means of a lock nut 68 for instance. It is in this manner that precise adjustment is possible even when the motor is under operating pressure.

In order to damp the abutment system each mating abutment 62 and 62' is provided with an elastic damping element or buffer 70. It is arranged on the pivoting lever 58 adjacent to a respective abutment part 69 (which runs onto a mating abutment 62 and 621 in order to limit the stroke) of the pivot lever 58. The two buffers 70 thus present extend in the direction of pivot 49 past the respective abutment part 69, which is buffer-free in the direction of pivoting. When it reaches on a mating abutment 62 and 62', there is thus engagement with a buffer 70, which absorbs energy as it is deformed until finally the buffered abutment part 69 runs onto the mating abutment, it thus defining the ultimate poEition. The buffer 70 may for instance be in the form of a ring member, which is slipped over the projecting abutment part 69. The two buffers 70 may be connected with each other on opposite sides by means of spacing means 71. It is in this manner that a generally elastic detent-locking part is provided which may be readily secured to the pivoting lever 58. The material for may be, for instance, the NBR plastic.

The adjusting device makes it possible to reset the pivot range for the pivoting piston 3, which prevents any contact bellweer, the pivoting vane 25 and the piston space divider. In order to produce the annular depression 64 it is possible to provide a central, sleeve like tall 72, which is surrounded with radial clearance by a concentrically arranged annular element 73. The depression 64 may in this respect be endowed with the desired form by suitable shaping of the two parts so that such form is advantageous for the guidance and attachment of the clamping elements 66.

It will be clear that in the piston space 2 adjacent to the piston space divider 30 there may be non-round or flattened areas 1 1 provided for fixation in position without for this reason leaving the scope of the invention.

The piston space divider (30) leads to an interruption of the annular space extending around the output drive member and, respectively, thebearing part so that there is a space for pivoting motion of at least 2700, the piston being located in such space.

4

Claims

1. A vane-type fluid power motor comprising a motor housing defining a piston space in which is located a vane piston adapted to oscillate during operation, the piston being connected in a torque transmitting manner, by means of a be aring member, with an output member which extends out of the piston space, and having a vane which extends substantially radially from the bearing member and is adapted to cooperate with mating surfaces on the housing in sealing manner so that the piston space is subdivided into two working spaces for driving fluid, the bearing member having a sealing surface which is at least partly cylindrical to extend in a circumferentially in relation to the axis of oscillation, the sealing surface being adapted to engage mating seal means on the housing when the motor is in operation, as seen looking the piston space, in the direction of the pivot axis, having a circular cross section, and a piston space divider being mounted in the piston space so as to make sealing contact with an inner wall surface of the piston space, and having the mating seal means thereon.

2. A vane-type motor as claimed in claim 1, characterized in that the motor housing is subdivided into two axially consecutive housing parts, having a 1 parting plane extending perpendicularly in relation to the pivot axis through the piston space.

3. A vane-type motor as claimed in claim 1 or 2, characterized in that the piston space divider is arranged in a detachable and replaceable manner in the piston space.

4. A vane-type motor as claimed in any one of the preceding claims 1 through 3, characterized in that the piston space divider placed in the piston space is interlockingly connected with the housing wall surrounding the piston space and in the case of a divided motor housing it is preferably interlockingly connected with both the housing parts.

5. A vane-type motor as claimed in claim 4, characterized in that the respective interlocking connection is a connection having male and female parts, and preferably at least one.interlocking member provided on the inner set of the housing wall adjacent to piston space and for instance in the form of an inteflocking member cooperates with an interlocking member arranged on the piston space divider and at least one interlocking connection is preferably located on a housing wall section on the axial side.

6. A vane-type motor as claimed in any one of the preceding claims 1 through 5, characterized in that the piston space divider has a stiffening element, on whose outer face there is a space divider seal cooperating with the inner face of the wall of the piston space, and which if appropriate bears the interlocking parts on the space divider.

7. A vane-type motor as claimed in claim 6, characterized in that the stiffening element consists of harder material than the space divider seal.

8. A vane-type motor as claimed in claim 6 or in claim 7, characterized in that the mating seal is formed at least partly and more particularly completely by a part of the stiffening element which at this postion is free of space divider seals, and preferably the sealing surface on the bearing part side is formed on a bearing part seal whose material is softer than the material of the stiffening element.

9. A vane-type motor as claimed in claim 6or in claim 7, characterized in that the space dividing seal is molded or cast on the stiffening element and preferably substantially completely surrounds same, possibly with the exception of the part forming the mating seal.

a f a

10. A vane-type motor as claimed in any one of the preceding claims 6 through 9, characterized in that space dividing seal has at least one sealing lip, which extends between the two end parts, extending towards the pivot axis, of the mating seal in the contact zone with the inner surface of the piston space about the stiffening element or the space dividing seal.

11. A vane-type motor as claimed in any one of the preceding claims 1 through 10, characterized by a setting device, provided outside the piston space, for setting the pivot angle of the pivoting piston, said setting device acting between the output drive member and a part fixed to the housing, more particularly the motor housing..

12. A vane-type motor as claimed in claim 11, characterized by a radially projecting pivoting abutment mounted in a torque transmitting manner on the output drive part and by a mating abutment, fixed to the housing and extending into the path of pivoting motion of the pivoting abutment, said mating abutment being able to be set as desired in the circumferential direction with respect to the pivot axis.

A vane-type motor as claimed in claim 12, characterized by a circular arcuate guide, secured to the motor housing, for the mating abutments and being centered an the pivot axis, such guide subtending an angle of 3600 about its center and more particularly being in the form of a ring.

14. A vane-type motor as claimed in claim 12 or in claim 13, characterized in that at least one mating abutment has a fine adjustment element, which more particularly comprises a set screw and extends into the path of pivoting of the pivoting abutment.

15. A vane-type motor as claimed in any one of the preceding claims 11 through 14, characterized in that adjacent to its abutment part cooperating with a mating abutment the pivoting abutment possess a buffer projecting past this abutment part and, more particularly, arranged adjacent to the abutment part in such a manner that prior to impingement of the abutment part setting the end postion of the pivoting motion on a mating abutment the associated buffer abuts the latter.

16. A vane-type motor as claimed in any one of the preceding claims 1 through 15, characterized in that the bearing part of the pivoting piston is in the form of a bushing formed integrally with the pivoting vane and its t X.

- 21 longitudinal axis coincides with the pivot axis and its circumferential face forms the sealing surface or is covered with a bearing part seal having the sealing surface.

17. A vane-type motor substantially as hereinbefore described with reference to the accompanying drawings.

18. Any novel subject matter or combination including novel subject matter herein disclosed, whether or not within the scope of or relating to the same invention as any of the preceding claims.

Published 1991 at Ihe Patent Office. State flouse. 66171 High Holborn. LondonWC I R 47P. Further copies maybe obtained from Sales Branch. Unit 6. Nine Mile Point Cwmfclinfach. Cross Keys, Newport. NPI 7HZ. Printed by Multiplex techniques ltd, St Mary Cray. Kent.