GB2074652A

GB2074652A - Rotary positive displacement devices

Info

Publication number: GB2074652A
Application number: GB8013265A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-04-22
Filing date: 1980-04-22
Publication date: 1981-11-04
Also published as: GB2074652B

Abstract

In a machine of the 'cat-and- mouse' type which may be an I.C. engine, a steam or air driven motor or a pump, a casing (50) having inlet and outlet ports (51, 52), and in an internal combustion engine an ignition port (53), contains a member (62) comprising a drive piston (64) and part (62a) of the wall of an annulus in which the drive piston (64) and a reactive piston (65) move and a member (63) comprising the reactive piston (65) and part (63a) of the wall of the annulus. The member (62) is drivably attached to a shaft (54), and the reaction member (63) connected to the shaft (54) via means which may comprise epicyclic or hypocyclic gearing or chain drive means associated with crank devices located within the casing member (50) or in a housing (20 in Figure 1, not shown) whereby during rotation of the drive piston (64) with respect to the casing (50) the reactive piston (65) moves alternately towards and away from the drive piston (64) while itself rotating with respect to the casing (50). <IMAGE>

Description

SPECIFICATION Improvements in positive displacement devices The present invention relates to positive displacement devices, particularly to prime movers such as internal combustion engines.

According to the present invention a positive displacement device comprises a piston and cylinder combination in the form of an endless annulus.

According to a feature of the invention the piston and cylinder combination may comprise a datum casing member having inlet and outlet ports, an action member comprising a drive piston and part of the walling of the annular cylinder, and a reaction member comprising a reactive piston and part of the walling of the annular cylinder.

Preferably the action and reaction members are adapted to rotate with respect to the casing, and thereby to cover and uncover the inlet and outlet ports.

According to another feature of the invention the action member may be drivably attached to an output drive shaft, and the reaction member associated with the drive shaft via reaction piston spatial control means whereby during rotation of the drive piston with respect to the casing the reaction piston moves alternately toward and away from the drive piston while itself rotating with respect to the casing.

The reaction piston spatial control means may comprise epicyclic or hypocyclic gearing or chain drive means associated with crank devices. The spatial control means may be located within the datum casing member or in housing distinct from the piston-cylinder combination.

In a preferred embodiment the device is an internal combustion engine, although it may be adapted as a stream or air driven prime mover or positive displacement pump.

Three internal combustion engines in accordance with the present invention wili now be described by way of example with reference to the accompanying drawing, of which: figure 1 is a part sectioned side elevation of the first engine, figure 2 is an end elevation of the first engine, figure 3 is an axial cross section of spatial control means to the first engine, figure 4 is a view on lV-IV in figure 3, figure 5 is a part sectioned side elevation of the second engine, and figure 6 is an axial cross section of the third engine.

The first engine, as illustrated in figures 1 to 4, has a datum casing member 10 defining an annular chamber 1 Oa into which are let inlet and exhaust and ignition ports 11, 12, 1 3 respectively.

A main drive shaft 14 enters the casing axially and carries rigidly mounted thereon an action member 1 5 comprising a drive piston support crank 1 5a having a cylinder wall portion 1 sub which fixedly supports two drive pistons 1 sic, in diametrically opposite locations.

Surrounding the main shaft 14 is a reaction member drive sleeve 1 6 carrying a reaction piston support member 1 7. The support member 17 comprises a support crank 17a, having a cylinder wall portion 17b, which fixed supports two reaction pistons 1 7c in diametrically opposite locations and facing corresponding drive pistons 15c.

The cylinder wall portions 15b and 1 7b are contiguous one with another and with the outer rim of the casing member 10, thus completing the annular chamber 1 Oa.

As illustrated in figure 2 the ignition port 1 3 is at top dead centre, the exhaust port 12, which has a collector groove 12a, is a few degrees before bottom dead centre, and the inlet port 11 about 40 after bottom dead centre.

The disposition of the sleeve 1 6 with respect to the main shaft 14 is controlled by reaction piston spatial control means shown in figures 3 and 4. In these figures a control means housing 20 pierced by the shaft 14 and the sleeve 1 6 supports an epicyclic static ring gear 21. Rigidly attached to the shaft 14 is a spatial control means drive plate 22 carrying freely rotatable thereon planet gears 23 integrally associated with spatial drive cranks 24 and meshing with the static gear 21. The sleeve 1 6 also carries fixedly a spatial drive receiver crank 25, and this is linked to the drive cranks 24 by connecting rods 36.In operation of this embodiment of the engine, as the shaft 14 rotates with respect to the housing in the direction indicated in figure 2, so of course do the spatial control means drive plate 22 and the action member 15 with both the pistons 15c. The gears 23, carried around by the plate 22, are caused to roll on the static gear 21 and rotate the spatial drive cranks 24. By virtue of the connecting rods 36 the receiver crank 25, and hence the sleeve 1 6 and the reaction member 1 7 and pistons 1 7c thus rotate with the shaft 14 but at alternately faster and slower rates so that the pistons 1 sic and 1 7c are closest together at top and bottom dead centres and furthest apart at 90 before and after.

In relation to the ports this means that a pair of pistons 1 sic and 1 7c passing the inlet port 11 are opening and hence draw combustibles through the inlet. Shortly after they have passed that port, i.e. at 90 before TDC they begin to move closer together and compress the combustibles. At TDC ignition occurs, driving the pistons apart and in particular imparting further momentum to the pistons 1 sic and the shaft 1 4. At about 90 after TDC the pistons begin to move closer together again in order to drive the combustion products out of the exhaust port 12.At the same time as one pair of pistons 1 sic and 1 7c are at any one stage in the engine cycle, e.g. compression, the other pair of pistons are at the diametrically opposite part of the cycle, i.e. exhaust.

In the embodiments illustrated in figure 5 parts similar in nature and function to those of the embodiment illustrated in figures 1 to 4 are referenced with similar final digits but are in the 30's and 40's.

Thus the engine shown in figure 5 comprises a datum casing member 30 defining an annular chamber 30a into which are let inlet, exhaust and ignition ports 31,32 and 33 respectively. The main drive shaft 34 carries integrally an action member 35 including a pair of drive pistons 35c.

The reaction member drive sleeve 36 freely surrounds the shaft 34 and carries integrally a reaction piston support member 37 including a pair of reaction pistons 37c. Reaction piston spatial control means are, in this embodiment, located within the housing 30 which itself supports a hypocyclic static ring gear 41. The action member 35 carries freely rotatable thereon a pair of planet gears 43 integrally associated with spatial drive cranks 44 and meshing with the static gear 41. The reaction piston support member 37 carries a drive journal 45 linked to the drive cranks 44 by connecting rods 46.

The embodiment shown in figure 6 comprises a casing 50 defining an annular chamber 50a and inlet, exhaust and ignition ports 51, 52, and 53 respectively. A main drive shaft 54 carries integrally a planet gear support rotor 55 carrying freely rotatable thereon two planet gears 56. The gears 56 are each associated integrally with diametrically oppositely disposed drive and reaction input cranks 57 and 58. A spur shaft 60 rigidly mounted in the casing 50 rigidly supports a static epicyclic gear 61 with which mesh the planet gears 56.

Action and reaction members 62 and 63 are carried freely rotatably on the drive and spur shafts 54 and 60 respectively. The members 62 and 63 each have part cylinder wall forming portions 62a and 63a respectively and respectively rigidly carry drive and reaction pistons 64 and 65. Journals 66 and 67 rigidly carried on the members 62 and 63 are respectively drivably linked to the drive and reaction input cracks 57 and 58 by connecting rods 68 and 69.

In operation of the engine illustrated in figure 6 the force separating the drive and reaction pistons caused by the ignition of combustibles is transmitted via both the drive and reaction members 62 and 63 and the connecting rods 68 and 69 to the cranks 57 and 58. These cranks rotate the gears 56 which roll on the static gear 61 and cause the rotor 55 and hence the shaft 54 to rotate.

It is appreciated that many modifications and refinements to the present invention will occur to those skilled in the art. In particular the annular chamber, and hence the pistons, may be circular in cross section, or at least have circular inner and outer section surfaces with flat axial walls.

Sealing/lubricating/bearing members may be carried in the casing and the drive and reaction members. The drive and reaction members may carry porting plates or pistons of differing lengths to block off the inlet and exhaust ports when these are not intended to supply or exhaust gases. In this way the interior of the casing with the exception of the annular cylinder may enciose an oil bath. The prime mover may readily be constructed to operate on either two or four stroke cycles, and the internal drives may be chain as distinct from merely gear, driven.

Among the advantages machines in accordance with the present invention offer over those known are included the fact that hot and cooler temperature zones are separate, piston side thrust can be minimised, valve operating gear as such can be obviated, and the number of moving parts of the engine which can be symmetrically balanced can be maximised, thus minimising vibration and wear.

Claims

1. A positive displacement device comprising a piston and cylinder combination in the form of an endless annulus.

2. A device as in Claim 1, wherein the piston and cylinder combination comprises a datum casing member having inlet and outlet ports, an action member comprising a drive piston and part of the walling of the annular cylinder, and a reaction member comprising a reactive piston and part of the walling of the annular cylinder.

3. A device as in Claim 2, wherein the action and reaction members are adapted to rotate with respect to the casing, and thereby to cover and uncover the inlet and outlet ports.

4. A device as in Claim 3, wherein the action member is drivably attached to an output drive shaft, and the reaction member is associated with the drive shaft via reaction piston spatial control means whereby during rotation of the drive piston with respect to the casing the reaction piston moves alternately toward and away from the drive piston while itself rotating with respect to the casing.

5. A device as in Claim 4, wherein the reaction piston spatial control means comprises epicyclic or hypocyclic gearing or chain drive means associated with crank devices.

6. A device as in Claim 4 or Claim 5, wherein the spatial control means is located within the datum casing member.

7. A device as in Claim 4 or Claim 5, wherein the spatial control means is located in housing distinct from the qiston-cylinder combination.

8. A device as in any one of the preceding Claims and adapted as an internal combustion engine.

9. A device as in any one of Claims 1 to 7 and adapted as a stream or air driven prime mover.

10. A device as in any one of Claims 1 to 7 and adapted as a positive displacement pump.

11. An internal combustion engine substantially as hereinbefore described with reference to Figures 1 to 4, or Figure 5, or Figure 6 of the accompanying drawings.