JPS6056881B2 - rotary piston device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary piston device.

Fluid valve mechanisms for rotary piston devices have the problem of internal fluid leakage between the metal-to-metal seal surfaces at both ends of the rotary valve member.

Therefore, to expect satisfactory operation, the seal play or tolerance factor between the metal-to-metal contact surfaces must be extremely precise, which is not easy to achieve on a production basis. . Matching very narrow tolerances between metal-to-metal sealing surfaces is a problem, made even more difficult by frictional thermal expansion of the metal-to-metal mating surfaces.

If the seal clearance is too narrow, abrasion will occur at the contact area between the metal surfaces. Traditionally, these metal-to-metal sealing surfaces have been lapped to close tolerances, but this is expensive. The ideal sealing condition or tolerance factor allows for a limited amount of fluid leakage between the surfaces of the metal-to-metal contact for the required lubrication to prevent thermal expansion and the occurrence of scratches. This is to prevent excessive leakage.

Excessive leakage not only reduces the volumetric efficiency of the rotary piston device, but also reduces the switching fluid port and
This tends to impede the satisfactory operation of the passageway structure.

If excessive leakage continues to occur despite alignment of the switching fluid passages, the alignment should be "opened" or
There is a risk that the timing sequence of "close" will be disturbed. The present invention includes a rotary valve member having a switching valve at one end and a flat sealing surface at the other end, and is constructed to allow a limited amount of leakage for the required lubrication.

The risk of excessive leakage is that the interfacial ring seal has a small interfacial area compared to that of the switching interfacial valve, and the rotary valve member 28 leaks fluid within the outer valve chamber 80. a radially formed outer flange surface 60 which is subjected to pressure and a radially formed inner flange surface 61 which is subjected to fluid pressure within said inner valve chamber 81; the rotary valve member 28 drives the rotary valve surface 27 toward the fixed valve member 29;
The seal ring surface 19 is connected to the flat ring surface 1.
6, one of the ring surfaces 16, 19 is a wear-resistant main surface and the other is a wear-resistant main surface when the rotary valve member 28 rotates. 1. A rotary piston device, characterized in that it is constructed of an abrasive slave surface which has a lower abrasion resistance compared to that of a rotary piston and is therefore subject to wear. The rotary motor according to claim 1, wherein the second major surface is made of a hard metal, and the abrasive minor surface is made of a soft metal and is configured to be subjected to abrasion and polishing by the hard metal.
piston device.

3. The rotary piston device according to claim 1, which has a housing in which the rotary valve member ↑u is rotatably attached, and the abrasion follower surface is integrally formed with the housing. .

4. The rotary piston device according to claim 2, wherein the abrasive subordinate surface made of soft metal is subjected to abrasion polishing by the surface made of hard metal.

5. Claim 1, in which the abrasive subordinate surface is a basic surface that has only been initially cut by a cutting tool of a rotating machine tool.
The rotary piston device described in Section 1. 6. The rotary screw according to claim 2, wherein the abrasive subordinate surface is polished. tons of equipment.

7. The surface made of hard metal and the rotary valve surface ↑J have substantially the same hardness.
The rotary piston device described in Section 1.

8. A rotary piston arrangement according to claim 1, wherein the eight planar ring surfaces (16) are axially immobile and axially unforced.

9. A rotary piston arrangement according to claim 1, wherein the seal ring surface 19 and the planar ring surface 16 form an annular interface area therebetween.

10 said series and other series of switching fluid passages 83,8
4 is formed by providing a plurality of openings in the outer flange surface 60, and the other is formed by providing a plurality of openings in the inner flange surface u±.
The rotary piston device according to claim 1, wherein the rotary piston device is formed by providing a plurality of openings in the rotary piston device.

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to rotary piston devices.

The fluid valve mechanism of a rotary piston device has a problem in that internal fluid leakage occurs between the surfaces of the metal-to-metal seals at both ends of the rotary valve member.

Therefore, to expect satisfactory operation, the seal play or tolerance factor between the metal-to-metal contact surfaces must be extremely precise, which is not easy to achieve on a production basis. . Matching very narrow tolerances between metal-to-metal sealing surfaces is a problem, made even more difficult by frictional heat expansion of the metal-to-metal mating surfaces.

If the seal clearance is too narrow, abrasion will occur at the contact area between the metal surfaces. Traditionally, these metal-to-metal sealing surfaces have been lapped to close tolerances, but this is expensive. The ideal seal condition or tolerance factor is one that allows a limited amount of fluid leakage between the surfaces of metal-to-metal contact for the required lubrication to prevent thermal expansion and the occurrence of scratches). This is to prevent excessive leakage.

Excessive leakage not only reduces the volumetric efficiency of the rotary piston device, but also reduces the switching fluid port and
This tends to impede the satisfactory operation of the passageway structure.

If excessive leakage continues to occur despite mutual alignment of the switching fluid passages,
There is a risk that the timing order of closing may be disturbed. The present invention
The rotary valve member has a switching valve at one end and a flat sealing surface at the other end and is constructed to allow a limited amount of leakage for the required lubrication.

The risk of excessive leakage is completely excluded. A seal having a flat contact surface is composed of a major surface and a minor surface that are in contact with each other. The major surface is comprised of a hard or hard metal and is configured to resist wear. The secondary surface is made of soft or low hardness metal. and has lower wear resistance than that of hard metals. Upon assembly, the hard metal surface and the soft metal surface form a tight metal-to-metal fit with each other. When the surfaces are subjected to relative rotation, the soft metal surface is arranged to undergo abrasive abrasive action by the hard metal surface and can be referred to as an abrasive minor surface. As soon as the required lubricating fluid begins to ooze or flow between the two surfaces, that is, at the contact area, as occurs when there is a mutual rubbing action between hard and soft metal surfaces, the abrasive action ceases at that moment.

Therefore, soft metal surfaces are subject to abrasion and abrasion)
, it will never be worn out. The depth of the abrasion play between hard and soft metal surfaces is related to the abrasion abrasion experienced by the soft metal surface at the time the required lubrication flow begins between the surfaces, and is dependent on assembly or processing tolerances. It is within. With a view to providing controlled leakage to provide the required lubrication, the seal play due to machining tolerances or abrasion is ideal when abrasion is performed as the circumstances require, which also It is even possible to match the viscosity or concentration of the working fluid used in the rotary piston device. The soft metal surface before being subjected to abrasion polishing may only be finished by cutting with a rotary machine tool. The hard metal surface is pushed away from the soft metal surface by the fluid pressure, so that the soft metal surface is not worn out and a suitable gap is maintained between the two metals.

It is an object of the present invention to provide a rotary piston system having components with abrasive seal play or tolerance factors that permit the necessary lubrication but do not permit excessive fluid leakage.

Another object is to provide a rotary piston device with a seal clearance configured to undergo abrasion but not wear out.

Yet another object is to provide a rotary piston device configured to force a hard metal surface away from a soft metal surface so that the soft metal surface is not subject to wear.

Yet another object is to provide a rotary piston device configured to polish and smooth soft metal surfaces. Still another object is to provide a rotary piston device having a soft metal surface that has only been finished by cutting with a rotary machine tool before being subjected to abrasion polishing.

The present invention constitutes a rotary piston device as follows.

That is, an outer fixed member or stator having a fixed axis, an inner rotating member or rotary having a rotating axis, and a pair arranged oppositely so that when one is pressurized, the other is depressurized. a housing having a fluid port, the fixed member and the rotating member forming a plurality of expandable and deflated piston chambers. This rotary piston device further includes a fluid valve mechanism that switches and connects the piston chamber to the fluid port, and this valve mechanism includes a rotary valve member, a fixed valve member, and a main shaft driven by the rotating member. are doing. The rotary valve member has a central socket and the main shaft has a hollow shaft or hollow extension fitted within the socket to drive the rotary valve member relative to the fixed valve member. ．． and forming a non-rotatable connection between the socket and the socket. The fixed valve member is provided on the fixed axis (between the rotary valve member and the piston chamber) and has a plurality of fluid holes arranged around the fixed axis with circumferential gaps. The fluid holes are configured to be in constant fluid communication with the piston chamber. The fluid valve mechanism further includes an outer valve chamber that is always in fluid communication 5 with one of the pair of fluid ports, and an inner valve chamber that is always in fluid communication with the other of the pair of fluid ports. have. Further, the housing has a wall formed with a planar ring surface, and the rotary valve member has a rotary valve surface in sealing engagement with the stationary valve member to form a switching interface valve therewith.
a first seal ring surface extending from the outer valve chamber to the rotary valve surface and having a seal ring surface in sealing engagement with the planar ring surface and forming an interfacial ring seal therewith; It has a series of switching fluid passages and a second series of switching fluid passages extending from the inner valve to the surface of the rotary valve. The first and second switching fluid passages are configured to switchably connect the outer valve chamber and the inner valve chamber to the fluid apertures of the stationary valve member during rotation of the rotary valve member. The rotary piston device of the present invention having the above configuration is characterized in that the switching interface valve has a large interface area, and the interface ring seal has a small interface area compared to the switching interface valve. the rotary valve member has a radially formed outer flange surface which is subjected to fluid pressure in the outer valve chamber; and a radially formed outer flange surface which is subjected to fluid pressure in the inner valve chamber. an inner flange surface formed in a direction, the rotary valve member having a fluid pressure actuating force to drive the rotary valve member toward the stationary valve member and to move the seal ring surface away from the planar ring surface. When the rotary valve member rotates, one of the two ring surfaces has a main surface that is resistant to wear, and the other has lower wear resistance than the same main surface, and is therefore resistant to wear. The structure includes an abradable follower surface that can be applied. Further objects of the invention and an understanding of the saw layer of the invention will be gained from the following description of preferred embodiments of the invention, taken in conjunction with the accompanying drawings.

The rotary piston device embodying the invention is preferably, but in no way limited to, a fluid motor. Referring now to the drawings, it will be understood that the present invention may be incorporated therein. Generally speaking, the rotary piston device is as follows:
It has a housing 20 having a substantially rectangular cross section.

The left end of this housing is provided with a flange for mounting a rotary piston device by means of a plurality of suitable screws 26, only one of which is shown in the drawing. 21 is fixed. The housing is hollow and is provided in its middle with an internal wall 22 having a central opening 15, which generally divides the hollow housing into left and right compartments. The interior wall has a flat blank surface or ring surface 16. A main shaft 25 is rotatably provided in the left-hand compartment, the main shaft 25 having an axis substantially coinciding with the longitudinal axis of the rotary piston arrangement. This main shaft 25 passes through the flange 21 and the housing 2
It has a small diameter outer portion 41 extending axially outwardly at 0, and has a large diameter inner portion. This large diameter inner portion is preferably supported by tapered roller bearings 42, 43 which provide radial thrust as well as axial end thrust. Male thread 5
A tightening nut 54 that is threadedly engaged with the tapered roller bearing 4
2, 43 are fixed to the main shaft 25 against axial movement. Note that the tightening nut 54 may be provided with a built-in locking structure to prevent loosening. l The compartment on the right is a valve compartment with a square fixed valve member 29 at its open end.
is attached by screws 30 (FIG. 3).

The valve member 29 has a fixed valve surface 37 substantially parallel to and axially spaced apart from the blank surface 16 . A rotary valve member 28 is provided between the valve surface 37 in the valve compartment and the flat blank surface 16, which is connected to a gear consisting of an outer fixed member or stator 32 and an inner rotating member or rotor 33. The rotary member (GerOtOr) 31 is configured to be rotationally driven with respect to a fixed valve surface 37 to control the flow of fluid into and out of the rotary component (GerOtOr) 31 . In operation, stator 32 and rotor 3
3 forms an inflatable and deflated piston chamber. Stator 32 and rotor 33 are covered by end cap 34, all of which are secured to stationary valve member 29 by screws 35. Fluid is sent into and out of the housing 20 through a pair of fluid ports 23 and 24. A connecting pivot shaft or valve drive means 36 connects the rotary valve member 28 and the rotor 33, whereby the rotary valve member is driven in rotation at the same speed as that of the rotor 33. The tapered roller bearings 42 and 43 constitute a common bearing means for the main shaft 25 and the rotary valve member 28. This common bearing means supports the main shaft 25 directly and the rotary valve member 28 indirectly through an extended drive means constituted by a hollow shaft 44 integrally connected to the main shaft 25. A hollow shaft 44 extends axially within the central opening 15 of the inner wall 22 and projects into the valve compartment and forms a driving connection with the rotary valve member 28 for actuation thereof. Attached to the extended end of the hollow shaft 44 is a male shank 45 (FIG. 2), which fits snugly into a central female socket 46 provided in the rotary valve member 28 (see FIG. 2). (See Figure 5). The connection is such that the tongue 17 and the axial slot 18 into which it fits are mutually non-rotatable and rotate the rotary valve member 28 when rotated by the main shaft. This connection also allows axial free movement between the rotary valve member 28 and the hollow shaft 44, allowing axial movement of the main shaft without any hindrance to the operation of the rotary valve member 28. There are things. The fixed valve member 29 is arranged on a longitudinal axis 38 about which the rotary valve member rotates.

This fixed valve member 29 is provided between the rotary valve member 28 and the gear-like rotating component 30, and has a plurality of fluid holes 48 arranged annularly around the axis 38, and is always connected to the piston chamber. In fluid communication. As shown in FIG. 6, the rotary valve member 28 has a flange body 40 and a hollow extension body 50 extending axially therefrom.

The flange body 40 has a rotary valve surface 27 which faces in sealing contact with the previously mentioned fixed valve surface 37 and together with the fixed valve surface forms a switching interface valve. Hollow extension body 50
The extended end is in the form of a seal ring surface or hollow blank surface 19, which faces the aforementioned flat blank surface 16 in sealing contact and which
6 constitutes a blank interface seal. The hollow blank surface 19 and the rotary valve surface 27 shall have substantially the same hardness. The rotary valve member 28 has an outer valve chamber 8
0 and an inner valve chamber 81 are formed. Outer valve chamber 80 surrounds rotary valve member 28 and is always in fluid communication with fluid port 23 . An inner valve chamber 81 is located within the rotary valve member 28 and is connected to the fluid port 24 via the central port 15 and also to the hollow shaft 44.
is in constant fluid communication with its surroundings. The outer valve chamber 80 and the inner valve chamber 81 are oppositely pressurized such that when one is pressurized the other is at a lower pressure.

As a result, fluid tends to leak from one valve chamber into the other. Such fluid leakage, referred to as internal leakage, occurs between the constituent surfaces of the switching valve at one end of the rotary valve member 28 and between the constituent surfaces of the blank interface seal at the other end of the rotary valve member 28. . Therefore, fluid leakage problems occur specifically between the rotating valve surface 27 and the fixed valve surface 37 at one end of the rotary valve member 28 and
It may be related to machining or assembly tolerances or sealing play between the hollow blank surface 19 and the flat blank surface 16 at the other end. In this manner, the outer and inner valve chambers 80 and 81 are separated from each other by the two sets of interfacial surfaces in close sealing contact. The hollow blank surface 19 forms an annular contact area with the flat blank surface 16. The rotary valve surface 27 is the fixed valve surface 3
7, forming a larger interfacial area compared to the annular contact area. The rotating valve surface 27 and the fixed valve surface 37 are
Preferably it is constructed of metal which is provided to resist frictional wear. Due to the high interfacial area and resistance to frictional wear, the rotating valve surface 27 and the stationary valve surface 37 are substantially free from frictional wear. As shown, rotary valve member 28 includes one series of switching fluid passages 83 extending from outer valve chamber 80 to rotary valve surface 27 and another series extending from inner valve chamber 81 to rotary valve surface 27. A switching fluid passageway 84 is formed.

These fluid passages 83 and 84 are arranged alternately with respect to each other so as to alternately connect the outer valve chamber 80 and the inner valve chamber 81 to the fluid hole 48 of the fixed valve surface 37 during rotation of the rotary valve member 28. It is composed of Switching fluid passage 8
3 and 84, the number is one less than the number of fluid holes 48 in the fixed valve surface 37. Flange body 40
has a radially formed outer flange surface 60 which is acted upon by fluid pressure within the outer valve chamber 80 and an inner valve chamber 81.
and a radially-shaped inner flange surface 61 that is subjected to fluid pressure within the rotary valve member 28, which configuration causes the rotary valve member 28 to urge the rotary valve surface 27 toward the fixed valve surface 37 during operation of the rotary valve member 28. , are adapted to undergo an axial fluid force acting in a direction that reduces internal fluid leakage between them.

This is 1 open J for alignment of switching fluid passages.
The timing sequence of closing means that there are no disturbances, which would be a concern if there were excessive fluid leaks between approaching surfaces. According to one object of the invention, the hollow extension 5
The hollow blank surface 19 of the extended end of the rotary valve member 28 has a hard metal major surface to withstand wear during rotation of the rotary valve member 28.

The flat blank surface 16 that rotates on or in contact with this main surface has lower wear resistance than that of the main surface and is therefore an abrasive subordinate surface made of a soft metal that is subject to abrasion and polishing. . In assembling the rotary piston device described above, the hard and soft metal surfaces are attached to each other in a tight metal-to-metal fit with specifications that permit virtually no fluid leakage.

The soft metal surface is configured to undergo abrasion and polishing by the hard metal surface when relative rotation occurs between the two surfaces. This abrasive action ceases the moment the required lubrication begins to seep or flow between the hard and soft metal surfaces. The depth of the gap formed when soft metal undergoes abrasion and polishing depends on tolerance factors such as machining and assembly between the hard and soft metal surfaces. Essentially, this tolerance factor is the soft metal surface that wears to provide an ideal seal as the circumstances require, and the viscosity or concentration of the working fluid used in the rotary piston device. It can even be adapted to During abrasion polishing, the hard metal surface polishes the soft metal surface to make it smooth. child)
It should be noted that when polished, the soft metal surface hardens itself slightly, making it resistant to further wear. Prior to being polished, the soft metal surface may be finished by cutting with a conventional rotary machine tool, which most skilled workers would be reluctant to employ as unsuitable for forming a sealing surface. In operation, the rotary valve member 28 is hydraulically forced to separate the hard metal surfaces from the soft metal surfaces, thereby protecting the soft metal surfaces from abrasion. The tolerance factors will always be ideal, ie, as the circumstances require, regardless of manufacturing variations in precision of the metal-to-metal fit during initial assembly. ! The accuracy of the initial fit from a production standpoint is not critical as long as abrasive soft metals are used. The degree of fit or contact of the initial seals does not need to maintain close tolerances to the degree that is required in the case of lapping. The basic surface produced by machining with a rotary machine tool is sufficient for the initial fit and subsequent polishing. Additionally, this method is not as expensive as a lap fit. In the present invention, the planar blank surface 16 is configured to be axially immobile and not forced in the same direction.

As can be seen, the present invention is free of any compression springs or other axial forcing members adapted to force the rotating valve surface 27 onto the fixed valve surface 37 to reduce fluid leakage. be. The tolerance factor due to wear is what provides the device with an ideal sealing mechanism without resorting to springs or other telescopic members. Note that the present invention also lacks any O-rings or gas sockets. Although the present invention has been described in detail with respect to the preferred embodiments to some extent, it is important to note that the disclosure of the preferred embodiments in this specification is merely for illustrative purposes. It will be appreciated that many changes may be made in details of construction, combination and assembly without departing from the spirit and scope of the claims set forth at the outset of this specification.

[Brief explanation of drawings]

FIG. 1 is a longitudinal partial cross-sectional view of a rotary piston device embodying the features of the present invention, a cross-sectional view of the rotary valve member is taken along line 1-1 in FIG. 4, and FIG. FIG. 3 is a schematic illustration of a male shank configured to fit snugly into a female socket of the member and to be mutually non-rotatably connected thereto, and attached to an extended end of a hollow shaft;
Figure 3 shows the male shank rotated 900 degrees from the position shown in the figure; Figure 3 is a front view of the fixed valve member along line 3-3 in Figure 1; A diagram showing the front of the rotary valve member along line 4, Figure 5 is similar to Figure 1 5-5.
FIG. 6 is an enlarged partial cross-sectional view showing the upper half of the rotary valve member in FIG. 1, showing additional symbols to those shown in FIG. FIG. 7 is a view taken along the line 7-7 of FIG. 1 and showing the stator and rotor of the rotary piston device. 16... Flat blank surface, 23, 24... Fluid port, 27... Rotary valve surface, 28... Rotary valve member, 29... Fixed valve member, 32... Stator, 3
3... Rotor, 36... Valve drive drive means or connection rocking shaft, 37... Fixed valve surface, 38... Shaft, 40...
...Flange body, 48...Fluid hole, 50...Extension body, 60...Outer flange surface, 61...Inner flange surface, 80...Outer valve chamber, 81...Inner Oriental chamber, 83
, 84...Switching cage passage.

Claims (1)

[Scope of Claims] 1. A rotary piston device comprising an outer fixed member or stator 32 having a fixed axis and an inner rotating member or rotor 3 having a rotational axis.
3, and a housing 20 having a pair of fluid ports 23 and 24 arranged oppositely so that when one is pressurized, the other is depressurized, and the fixed member 32 and rotating member 33 expand and contract. While forming a possible plurality of piston chambers, the device further includes a fluid valve mechanism for switchingly connecting said piston chambers to said fluid ports 23, 24, said valve mechanism being connected to a rotary valve member. 28, has a main shaft 25 driven by a fixed valve member 29 and the rotary member 33, the rotary valve member 28 has a central socket 46, the main shaft 25 is driven by the socket 4;
6 and forming a non-rotatable connection between the hollow shaft 44 and the socket 46 for driving the rotary valve member 28 with respect to the fixed valve member 29. The fixed valve member 29 is located on the fixed axis and is provided between the rotary valve member 28 and the piston chamber, and is arranged at intervals in the circumferential direction around the fixed axis. Multiple fluid holes 4
8, and the fluid port is configured to be in constant fluid communication with the piston chamber, and the fluid valve mechanism further includes one of the pair of fluid ports 23, 24. The housing 20 has an outer valve chamber 80 in constant fluid communication with the other of the fluid ports, and an inner valve chamber 81 in constant fluid communication with the other of the same fluid ports.
The rotary valve member 28 has a wall 22 formed with a rotary valve surface 27 in sealing engagement with the stationary valve member 29 to form a switching interface valve therewith, and a rotary valve surface 27 formed with the planar ring surface 16. from said outer valve chamber 80 to a rotary valve surface 2 having a sealing ring surface 19 in intimate sealing engagement and forming an interfacial ring seal therewith.
7 of the first series of switching fluid passages 83 formed.
and a second series of switching fluid passages 84 formed extending from the inner valve chamber 81 to the rotary valve surface 27,
These switching fluid passages 83 and 84 are connected to the outer valve chamber 80 and the inner valve chamber 8 when the rotary valve member 28 rotates.
1 to the fluid hole 48 of the stationary valve member 29, the switching interface valve having a large interface area, and the interface ring seal having a large interface area. a radially formed outer flange having a small interfacial area compared to that of a switching interface valve, the rotary valve member 28 being subject to fluid pressure within the outer valve chamber 80; surface 6
0 and a radially formed inner flange surface 61 which is subjected to fluid pressure within said inner valve chamber 81;
The rotary valve member 28 is configured to be subjected to fluid pressure operative to drive the rotary valve surface 27 toward the stationary valve member 29 and to move the seal ring surface 19 away from the planar ring surface 16. and both ring surfaces 1
6 and 19, one of which is a main surface that has abrasion resistance when the rotary valve member 28 rotates, and the other is an abrasive subordinate surface that has lower abrasion resistance than the main surface and can therefore be subjected to abrasion. A rotary piston device comprising: 2. The rotary piston device according to claim 1, wherein the major surface is made of a hard metal and the abrasive minor surface is made of a soft metal and is configured to undergo abrasion and abrasion by the hard metal. 3. The rotary piston device according to claim 1, comprising a housing 20 in which a rotary valve member 28 is rotatably mounted, and wherein the wear-following surface is integrally formed with the housing. 4. The rotary piston device according to claim 2, wherein the abrasive subordinate surface made of soft metal is subjected to abrasion polishing by the surface made of hard metal. 5. The rotary piston device according to claim 1, wherein the abrasive subordinate surface is a basic surface that is simply cut by a cutting tool of a rotary machine tool. 6. The rotary piston device according to claim 2, wherein the abrasive subordinate surface is polished. 7. A rotary piston device according to claim 2, wherein the hard metal surface and the rotary valve surface 27 have substantially the same hardness. 8. Claim 1 in which the planar ring surface 16 is configured to be axially immobile and axially unforced.
The rotary piston device described in Section 1. 9. A rotary piston arrangement according to claim 1, wherein the seal ring surface 19 and the planar ring surface 16 form an annular interface area therebetween. 10 said series and other series of switching fluid passages 83;
84 is formed by providing a plurality of apertures in the outer flange surface 60 and the other in the inner flange surface 6.
The rotary piston device according to claim 1, wherein the rotary piston device is formed by providing a plurality of openings in the rotary piston device.