US3337123A

US3337123A - Rotating-piston compressor

Info

Publication number: US3337123A
Application number: US597414A
Authority: US
Inventors: Bulutay Attila
Original assignee: Individual
Current assignee: Individual
Priority date: 1965-11-26
Filing date: 1966-11-28
Publication date: 1967-08-22
Anticipated expiration: 1984-08-22

Description

Aug. 22, 1967 BULUTAY 3,337,123

ROTATING-PISTON COMPRESSOR Filed Nov. 28, 1966 7 4 SheetsShee't 1 FIG. I

INVENTOR ATTILA" BULUTAY AGENT v Aug. 22, 1967 A. BULUTAY 3,337,123

' ROTATING-PISTON COMPRESSOR Filed Nov. 28, 1966 4 Sheets-Sh0et INVENTORY ATTILA BU'LUTAY zwi AGENT Aug. 22, 1967 A. BULUTAY ROTATING-PISTON COMPRESSOR Filed Nov. 28, 1966 4 Sheets-Sheet PEG. 5

mVE NTOR ATTILA BULUTAYY v Q BY AGENT United States Patent 3,337,123 ROTATING-PISTON COMPRESSOR Attila Bulutay, Kizilirmak Sokak 7/2, Akay, Ankara, Turkey Filed Nov. 28, 1966, Ser. No. 597,414 Claims priority, applicairgitzrig'lurkey, Nov. 26, 1965,

10 Claims. (or. 230-144 ABSTRACT OF THE DISCLOSURE Various types of compressors are known which use different principles for their operation. It has been determined some time ago that any oscillatory or irregular motion, such as that of reciprocating pistons, produces vibrations and subjects the compressor to undue wear. Thus, preference has been given to rotary-action compressors, among which are screw types, centripetal, centris fug-al, and other systems.

The present invention has as one of its major objects to dispense with the drawbacks and inherent disadvantages of hitherto used compressor types. A rotary-motion, forced-action compressor is provided which combines smooth operation with economical output and reliable performance.

It is another important object of the invention to provide such a compressor which allows a wide range of adjustability, for controlling the suction and compression phases, the output capacity, and/ or the ejection pressure of the inventive compressor, even independently from each other.

It is yet another object of the invention to dispense entirely with valves which are usually the source of disturbances in hitherto used types of compressors.

According to one of the important structural features of the inventive rotating-piston compressor, there are provided two coaxial shafts, preferably one hollow and surrounding the other, which are driven by respective universal-joint systems. The latter provide periodic advancing and lagging movements in the shafts, and the piston members associated therewith, while they rotate in the same direction but with different and changin peripheral velocities.

According to the invention, consecutive piston members within a common cylinder space define compression spaces or volumes which are periodically expanded and contracted during the rotation of the shafts with the piston members. Preferably, a phase difference of 90 is provided between the movements of the two shafts.

Another feature of the invention relates to the provision of a liner inside the cylinder body, preferably press-fitted thereinto, the liner having cut-outs which correspond in their lengths to the arcuate outer sides of the piston members. In a preferred, exemplary embodiment, this arrangement results in substantially identical operational phases for (A) suction, (B) suction with compression, and (C) compression, followed by a much shorter phase (D) of compression with suction. These phases repeat themselves twice during each revolution of the driving shaft.

In the inventive compressor, the shaft velocities are reduced twice and increased twice during one complete revolution of the two coaxial shafts. The resulting suction and compression allows the sucked-in air or other galses to be ejected or delivered to a tank or the atmosp ere.

Another feature of the invention relates to that the driving universal-joint systems are applied in a manner to present a phase difference. Thus the suction and compression ratios are increased to a maximum. The maximum slow-down in the velocity of the one shaft, and the maximum speeding-up of the velocity of the other, are synchronized and this is performed in a periodical manner, as has been mentioned before.

A further feautre relates to the adjustability of the suction and compression ratios, by simply changing the specific angle between the axis of the coaxial shafts, on the one hand, and the axis of the driving shaft, on the other hand.

Yet another feature relates to that different compression ratios may be obtained by the facility of making the rotating pistons with larger or smaller volumes therebetween, which thus vary the overall volume of the pistons, occupying the total cylinder space.

The suction and compression ratios of the inventive compressor can be brought to :any desired rating by changing the phase .difierence of the universal-joint sys-v tems of the two shafts to any desired degree.

Another feature of the invention relates to that the pairs of suction and compression sections in the cylinder space are kept unchanged during operation, without any relocation thereof. The channels leading to the afore-v mentioned sections make for uninterruped and continuous suction and compression, without the necessity for valves and/or flaps.

Yet a further feature of the compressor relates to the facility of operating the same even in reverse direction,

In this mode of'opera-tion, the suction sections and phases of course become compression sections and phases, and vice versa. Gas or air is then withdrawn through the outlet channels, and it is delivered through the intake channels.

Yet another feature of the inventive compressor relates to the expedientaccording to which the lubrication of the cylinder may be provided by dripping lubricants into the sucked-in air or gas, or spraying the lubricants into the cylinder through pin holes which can be opened to;

the suction sections of the cylinder.

The various objects, features and attendant advantages of the present invention will become more apparent from the following description of a preferred exemplary em-- bodiment of the rotating-piston compressor according to the-invention, when considered in conjunction withthe accompanying drawings, wherein FIG. 1 is a top view of the rotating-piston compressor according to the invention;

FIGS. 2a and 2b are partial vertical axial cross-sectional and side-elevational views of-the compressor shown in FIG. 1, taken along line 2a, 2b of FIG. 3, wherein FIG. 2a illustrates two universal-joint systems for providing a periodical phase difference between the velocities of the I two compressor shafts, while FIG. 2b illustrates the compressor proper;

FIG. 3 is a vertical cross-sectional view taken along line 3-3 of FIG. 2b;

'FIG. 4a is a sectional detail -view of the rotating pistons, taken along line 4a4a of FIG. 3;

FIG. 4b is another sectional detail view of the pistons, at right angles to FIG. 4a, taken along line 4b4b of FIG. 2b;

FIG. 5 is a schematic illustration of the specific angle between the driving and the driven shafts of the compressor; and

FIG. 6 is a schematic showing of the operational phases in the rotating pistons, similar to the showing of FIG. 3, for explanatory purposes.

The inventive rotating-piston compressor will now be described with reference to the top view of FIG. 1 and the partial views of FIGS. 2a and 2b, the two together showing the compressor on a somewhat enlarged scale so as to illustrate all important details. FIG. 3 and the detail views of FIGS. 4a, 4b give cross-sectional details of the rotating pistons and the operative spaces therebetween.

A bracket pad or plate 31 (omitted from FIG. 2:1 for the sake of clarity) serves as a chassis for the compressor which is secured thereto by way of nuts 47 and bolts 49, with spring washers 46, 48 being preferably interposed therebetween.

I The compressor is driven by an input shaft 1 forming part or being operatively connected with a suitable prime mover. Within the compressor, there are two driven shafts, namely an inner shaft 16 and a hollow shaft 17 surrounding the former. Before the actual compressor components canbe dealt with, the two universal-joint systems will be described, as shown in FIGS. 1 and 2a, which are interposed between the driving or input shaft 1, on the one hand, and the driven shafts 16, 17, on the other, so as to provide a periodical phase difierence between the velocities of these shafts, as will be fully explained hereunder.

Shaft 1 has connected thereto separate but coaxial and synchronously rotating yokes 32, 33, substantially perpendicular with respect to each other, to obtain 90 phase difference between said yokes, one for each universaljoint system. Following up first the yoke 32, which cooperates in driving the hollow shaft 17 with a periodically changing velocity, it is linked to conjugated ring members 4a, 4b by the intermediary of needle bearings 6 and lock rings 5 (see FIG. 2a). The members 4a, 4b are inter-connected by means of bolts and nuts 2.

In the position shown in FIGS. 1 and 2a, yoke 32 is substantially in the horizontal plane and ring members 4a, 4b are in a plane perpendicular to the yoke 32 and to the axis of shaft 1. At respective angles of A (shown in FIG. 5) and 180 minus A, a second yoke 38 is journ'aled to the ring members 4a, 4b, similarly by the intermediary of bearings 6 and lock rings 5. The illustrated, preferred embodiment. is made for A=40. The yoke 38 is perpendicular to the hollow shaft 17. As shown in the drawings, the two pairs of bearings cooperating with the ring members are disposed diametrally, and at right angles with respect to the other pair, for the driving and the driven yokes 32, 38, respectively.

, An oil seal 3 is shown between the bearings 6 and the limbs of yoke 38, and similar seals may of course be provided for the other junctions of this and of the other universal-joint system. By way of a key 9, the yoke 38 is axially connected for driving the hollow shaft 17.

As to the other yoke 33, which cooperates in driving the shaft 16 inside the shaft 17 and independently therefrom, it is linked to conjugated ring members 35a, 35b similar to but smaller than the afore-mentioned members 4a, 4b. It will be seen from the drawings that yoke 32 and rings 4a, 4b are larger than their counterparts 33, 35a, 35b, respectively, so that the system of shaft 16 can freely rotate within that of shaft 17 Here, again, there may be needle bearings and lock rings, as in the previously described universal-joint system. Bolts and nuts 34 serve for interconnecting the members 35a, 35b and they are of course the counterparts of bolts and nuts 2.

In the position shown in FIGS. 1 and 2a, yoke 33 is substantially in the vertical plane and ring members 35a, 35b are in -a plane at respective angles of 40 and 140 with respect to the yoke 33 and to the axis of shaft 1. In a plane perpendicular to the axis of shaft 16 and to the ring members 35a, 35b, a second yoke 37 is journaled to the latter, preferably also by the inter-mediary of bearings and lock rings. The bearing pairs are again disposed diametr-ally, at right angles for the driving and driven yokes 33, 37, respectively.

Oil seals 3 are again shown for this system. The yoke 37 is axially, directly (by way of a conventional key) or otherwise, connected to the end of shaft 16 for driving the same, independently from hollow shaft 17. An oil seal 8 may be interposed between the enlarged end of shaft 16 and the outer end of hollow shaft 17 so as to prevent lubricants to escape from between the two shafts, in a conventional manner.

The compressor proper includes a body 18. At the end where the shafts 16, 17 enter, there is a cap 11 having an oil seal 10 therein which surrounds the outer shaft 17.

Between the cap 11 and the body 18 there is a bearing cap 12 inside of which there are conventional needle bearings 13, with bushes 14 therebetween, for journaling the hollow shaft 17 and the shaft 16 therein. At one or more locations along the shaft 17, bearing needles 15 are disposed within annular or other appropriately shaped recesses around shaft 16, for journaling the same within shaft 17, so as to assist their rotation independent from each other. Packings 19 surround the shaft 17.

The previously mentioned FIGS. 2b, 3, 4a and 4b are referred to for most of the components to be described hereafter. Cylinder caps 20 straddle a cylinder body 21 which may be provided with heat-exchange fins, as shown in FIG. 3. Rotating piston members 23 and 58 are keyed to shafts 17 and 16, respectively, as shown in FIG. 3,

and members 23 have threaded bores therein for countersunk bolts 22 (see FIG. 2b). A cylinder liner 26 surrounds the piston members 23 and 58. The afore-Inentioned packings 19 are secured to cylinder caps 20 by way of packing bushes 28 and associated bolts 29. Liner 26 is press-fitted in body 21.

At the end of the compressor opposite the entrance of shafts 16, 17, cylinder cap 20 is flanked by another cap member 27 and at this end, a cap 30 is removably attached so as to allow access to the end of shaft 16. At the opposite compressor end, the cap 11 and the bearing cap 12 are held to the body 18 by means of bolts 39, gaskets 40 and 41 being respectively interposed between the aforementioned elements, as shown in FIGS. 1 and 2b. Plugs 36 and 42 are provided at strategic points of the compressor casing for allowing lubricants to be introduced and drained, respectively. Between portions of the casing 18, the caps 20 and the cylinder body 21, gaskets 44 and 45 are interposed; there is a similar gasket 50 between the cap member 27 and the end cap 30 of the compressor, as shown.

Numerals 51 identify attaching bolts similar to those shown at- 39, and mentioned before; appropriate nut-s 53 and optional spring washers 52 are also shown (e.g. in FIG. 1) between the structural elements of the compressor. Similarly, bolts 54 and spring washers 55 are provided for holding the elements together, in conjunction with nuts 56 (see FIGS. 1 and 2b).

Again referring to FIGS. 3, 4a and 4b, the piston members 58 associated with the shaft 16 are disposed at angularly offset locations with respect to the piston members 23 of shaft 17. Between the respective piston members 23, 58 and the shafts 17, 16, there are piston rings 62 (see FIG. 3) While on the outer sides of the members 58, facing the cylinder liner 26, there are additional piston rings 63. The latter are also shown in FIGS. 4a and 4b; in the former, springs 64 are also shown which are lodged in appropriate bores of the piston members 23 and 58. Each set of pistons and shafts can be made as a single unit. Referring now to FIGS. 1, 2b and 3 only, there are shown diametrally disposed inlet pipes 43 and 57, the latter being provided with a lubricating valve 24. In another plane, axially spaced apart from the plane of the inlet pipes, there are two diametrally disposed and preferably interconnected outlet or delivery pipes 25. The aforementioned pipes 43, 57 and 25 are preferably provided with sockets 60, coupling adapters 61, and gasket rings 59 interposed between the adapters 61 and the appropriately shaped connecting portions of the cylinder body 21.

In FIG. 3, operative compressing spaces 65, 66, 67 and 68 are formed between successive pairs of piston members 58 and 23 (then 23 and 58, and so forth). These spaces or volumes are aligned with respective channels 69, 70, 71 and 72, respectively connected with the aforementioned pipes 57, 25, 43 and 25, in this order. The operation of the compressor will be described as the description proceeds.

FIG. 5 is a schematic, explanatory illustration of the angular relationship between the shaft 1 and the shafts 16, 17; this view also shows the aforementioned specific angle A defined between the respective axes of these shafts, as will be explained somewhat later.

Coming now to the operation of the inventive rotatingpiston compressor, it will be understood from the structural description that, during their rotation, the shafts 16, 17 perform advancing and lagging movements relative to one another, as a result of which the volumes 65 to 68 between the pairs of rotating pistons 58, 23 periodically expand and contract. This provides the suction and discharge (intake and delivery) effects of the compressor. The diametrally opposite channels 69, 71 maintain constant suction while the other pair of channels 70, 72 discharges the compressed air or gases. The expansion and contraction of the volumes 65 to 68 takes place twice during each revolution of the driving shaft 1.

When volumes 65, 67 contract, that is in the compress ing position, volumes 66, 68 simultaneously expand, that is, they are at intake position. Subsequently, volumes 66, 68 become ready for compressing, and volumes 65, 67 for intake. This repeats itself periodically. The compression performed by the device is thus a rotary-motion, forced compression.

Channels 69, 71 in cylinder 21 maintain constant suction, that is air or gas is made to enter the cylinder. Simultaneously, channels 70, 72 maintain constant discharge of compressed air or gas from the cylinder. It should be noted that the lengths of the channels 69 to 72 substantially correspond, in peripheral direction, to the lengths of arcuate outer sides of the piston members 23, 58, owing to appropriate cut-outs provided in the cylinder liner 26, as shown in FIG. 3. Thus, the piston members 23, 58 completely block the entrances to the channels when they coincide with the liner cut-outs during their rotation.

Reference should be had at this point to the schematic, illustrative showing of the operational phases in the cylinder volumes, as shown in FIG. 6. For the sake of better understanding, the channels 69 to 72 and the respective cut-outs in cylinder liner 26 have been shown in a single plane rather than ofliset by pairs, as in actual construction (see FIG. 3). Since both expansion and contraction or compression take place twice during one revolution of the shafts 16, 17, there will be four distinct phases of operation during each half revolution, as identified in FIG. 6 by letters, to wit:

A-suction phase;

Bsuction phase, compressing section;

Ccompression phase; and

Dcompression phase, suction section.

The compression ratio can be adjusted by accordingly dimensioning the piston members 23, 58, as well as the angle A between the shaft 1 and the shafts 16, 17.

The output capacity of the compressor can be controlled by changing the rotational speed of the driving shaft 1 and/ or the volume of the cylinder 21.

The ejection pressure of the compressor may be increased by administering compressed air to the intake pipes 43 and/or 57.

Lubrication of the cyilnder 21 and of the shafts 16, 17 in the cylinder 21 is made possible, for example, by dripping lubricants into the air or gas entering the intake pipes 43, 57; the lubricating valve 24 shown for pipe 57 is an exemplary solution. Also, lubricant may be sprayed in by way of small holes provided in the cylinder caps 20 or the cylinder wall; another possible solution resides in spraying a lubricant in a similar manner into the intake sections of the cylinder caps, the pin holes (not shown) having direct connection with the layer of oil in the cylinder body. The lubricant which becomes intermixed with the compressed air or gas can be removed in a conventional way by oil retainers (not illustrated) to be disposed at the discharge end of the compressor.

It will be understood that the components of the compressor, and mainly the cylinder 21, the caps 20 and the shafts 16, 17, may be made of friction and corrosion resistant materials.

It should be noted that there is no need to provide either valves or any other similar means for the intake or discharge channels of the inventive rotating-piston compressor.

The compressor is self-cooled by way of the cooling or heat-exchange fins provided on the cylinder 21 and preferably also on the compressor body 18 (see FIGS. 1 and 2b). It is of course also possible to cool the inventive compressor by way of forced air from a fan. If required, water cooling can be provided by means of conventional water jackets attached to the body 18 and/or to the cylinder body 21.

For purposes of illustration, driving shaft 1 can be assumed to be rotated in the clockwise sense. However, it will be understood by those skilled in the art, that the shaft 1, and thus the compressor, may be rotated in the reverse, counter-clockwise sense. Then channels 70, 72

will maintain constant suction while channels 69, 71 provide constant discharge. The minor structural modifications of the respective inlet and outlet pipes 43 and 57, as well as 25 will be self-explanatory for operating the compressor in this alternative mode.

It is also possible to maintain single-channel suction or discharge, or both, by separately interconnecting the tWo intake and/or discharge channels 69, 71, and 70, 72, respectively, by suitable conduits or other means.

It will be understood that no specific means have been described and illustrated for performing the various adjustments which have been described earlier, like the variation of the dimensions of the piston members; the changing of the specific angle between the various shafts; the administering of compressed air into the intake pipes; the changing of the volumes between the piston members; the variation in the phase angle or difie-rence between the universal-joint systems of the two shafts, etc. These will no doubt be self-explanatory expedients to those skilled in the art.

The foregoing disclosure relates only to a preferred, exemplary embodiment of the invention compressor, which is intended to include all changes and modifications of the example described, within the scope of the invention as set forth in the preceding objects and/or the appended claims.

What I claim is:

1. A rotating-piston compressor for air and gases, comprising a driving shaft rotated by an extraneous prime mover at a substantially uniform speed; two driven shafts, one of them being hollow and coaxially surrounding the other; two universal-joint systems operatively interconnected between said driving shaft and said driven shafts, for simultaneously rotating said driven shafts with a phase difference and with periodically recurring independent speeding-up and slowing-down phases in the velocities of each driven shaft; a casing body including a closed cylinder body, a cylinder liner fitted into said cylinder body and defining a compression chamber; a pair of diametrally disposed piston members operatively connected with each driven shaft, the two pairs being normally perpendicular With each other, and rotatable within said compression chamber with a predetermined phase advance and phase lag in each pair of piston members, upon rotation of said driven shafts; a pair of diametrally disposed inlet channels through said cylinder body and said liner, and a pair of outlet channels spaced apart from said inlet channels along the common axis of said driven shafts, the spaces between successive piston members, connected with different driven shafts, periodically expanding and contracting so as to provide suction for air and gases through said inlet channels, and consecutively to provide compression for the air and gases to deliver the same through said outlet channels; said liner having cut-outs aligned with said inlet and said outlet channels and substantially corresponding in their lengths to the outer sides of said piston members, said cut-outs being longer than the diameters of said inlet and said outlet channels; whereby four distinct operational phases result during each half revoluiton of said driving shaft, three of said phases being of substantially identical length and including a suction phase for the air and gases, a suction phase with compression and a compression phase, followed by the much shorter fourth phase which is a compression phase with suction of the air and gases.

2. The compressor as defined in claim 1, wherein said phase difference is substantially 90 between the movements of said driven shafts.

3. The compressor as defined in claim 2, wherein said universal-joint systems each include ring members to which said driving and said driven shafts are operatively linked by yokes, one of said yokes in each system being perpendicular with respect to the connected shaft while the other yoke defines angles of 40 and 140 degrees with respect to the other connected shaft; the universal-joint system of one driven shaft being larger than the other so as to accommodate the latter within its ring members, With full freedom of rotation.

4. The compressor as defined in claim 3, wherein said yokes in at least one of said universal-joint systems ar disposed for pivotal connection with said ring members at diametrally opposite points on the side of said driving shaft, and at similar diametrally opposite points at right angles to the afore-mentioned points on the side of said driven shaft.

5. The compressor'as defined in claim 1, wherein at least said outlet channels are interconnected for common delivery of the air and gases, and wherein at least one of said inlet channels is provided with adjustable inlet means for a lubricant.

6. The compressor as defined in claim 1, further comprising at least one set of piston rings disposed on said piston members connected with at least one of said driven shafts, and spring means lodged in bores, of the aforementioned piston members for biasing said piston rings toward said cylinder liner.

7. The compressor as defined in claim 1, further comprising coupling adapters between at least a pair of said inlet and said outlet channels and corresponding portions of said cylinder body.

8. The compressor as defined in claim 7, further comprising cooling fins over at least a portion of said casing body.

9. The compressor as defined in claim 1, further comprising bearing means in said casing body for said hollow shaft, bearing needles between said driven shafts and accommodated in recesses of the surrounded driven shaft, and at least one oil seal associated with said driven shafts for preventing leakage of lubricant from said casing body.

10. The compressor as defined in claim 1, wherein operation is dependent upon at least one of the parameters of the phase difference between said universal-joint systems, said phase advance and said phase lag, the ratios between said opertaional phases, the specific angle between the axis of said driving shaft and the common axis of said driven shafts, the siZe of said spaces between successive piston members, the volume of said compression chamber, the output capacity and the ejection pressure, and further comprising means for varying at least one of the aforementioned parameters.

References Cited UNITED STATES PATENTS 1,502,756 7/1924 Thompson 103129 2,072,482 3/1937 Myard l03129 2,148,282 2/1939 Stevens 103-129 2,149,143 2/1939 Landenberger 103129 2,182,269 12/ 1939 WhritenOur 123-11 2,503,894 4/ 1950 Wildhaber 103129 2,553,954 5/1951 Bancroft 230144 2,642,807 6/1953 Linderman 12311 2,673,027 3/1954 Lipkau 23 0144 2,811,927 11/1957 Jansen 103129 3,061,180 10/1962 Durgin 230-144 3,139,871 7/1964 Larpent 123l1 FOREIGN PATENTS 976,094 10/ 1950 France. 465,211 5/1937 Great Britain.

DONLEY J. STOCKING, Primary Examiner.

W. I. GOODLIN, Assistant Examiner.

Claims

1. A ROTATING-PISTON COMPRESSOR FOR AIR AND GASES, COMPRISING A DRIVING SHAFT ROTATED BY AN EXTRANEOUS PRIME MOVER AT A SUBSTANTIALLY UNIFORM SPEED; TWO DRIVEN SHAFTS, ONE OF THEM BEING HOLLOW AND COAXIALLY SURROUNDING THE OTHER; TWO UNIVERSAL-JOINT SYSTEMS OPERATIVELY INTERCONNECTED BETWEEN SAID DRIVING SHAFT AND SAID DRIVEN SHAFTS, FOR SIMULTANEOUSLY ROTATING SAID DRIVEN SHAFTS WITH A PHASE DIFFERENCE AND WITH PERIODICALLY RECURRING INDEPENDENT SPEEDING-UP AND SLOWING-DOWN PHASES IN THE VELOCITIES OF EACH DRIVEN SHAFT; A CASING BODY INCLUDING A CLOSED CYLINDER BODY, A CYLINDER LINER FITTED INTO SAID CYLINDER BODY AND DEFINING A COMPRESSION CHAMBER; A PAIR OF DIAMETRALLY DISPOSED PISTON MEMBERS OPERATIVELY CONNECTED WITH EACH DRIVEN SHAFT, THE TWO PAIRS BEING NORMALLY PERPENDICULAR WITH EACH OTHER, AND ROTATABLE WITHIN SAID COMPRESSION CHAMBER WITH A PREDETERMINED PHASE ADVANCE AND PHASE LAG IN EACH PAIR OF PISTON MEMBERS, UPON ROTATION OF SAID DRIVEN SHAFTS; A PAIR OF DIAMETRALLY DISPOSED INLET CHANNELS THROUGH SAID CYLINDER BODY AND SAID LINER, AND A PAIR OF OUTLET CHANNELS SPACED APART FROM SAID INLET CHANNELS ALONG THE COMMON AXIS OF S AID DRIVEN SHAFTS; THE SPACES BETWEEN SUCCESSIVE PISTON MEMBERS, CONNECTED WITH DIFFERENT DRIVEN SHAFTS, PERIODICALLY EXPANDING AND CONTRACTING SO AS TO PROVIDE SUCTION FOR AIR AND GASES THROUGH SAID INLET CHANNELS, AND CONSECUTIVELY TO PROVIDE COMPRESSION FOR TH AIR OF GASES TO DELIVER THE SAME THROUGH SAID OUTLET CHANNELS; SAID LINER HAVING CUT-OUTS ALIGNED WITH SAID INLET AND SAID OUTLET CHANNELS AND SUBSTANTIALLY CORRESPONDING IN THEIR LENGTHS TO THE OUTER SIDES OF SAID PISTON MEMBERS, SAID CUT-OUTS BEING LONGER THAN THE DIAMETERS OF SAID INLET AND SAID OUTLET CHANNELS; WHEREBY FOUR DISTINCT OPERATIONAL PHASES RESULT DURING EACH HALF REVOLUTION OF SAID DRIVING SHAFT, THREE OF SAID PHASES BEING OF SUBSTANTIALLY IDENTICAL LENGTH AND INCLUDING A SUCTION PHASE FOR THE AIR AND GASES, A SUCTION PHASE WITH COMPRESSION AND A COMPRESSION PHASE, FOLLOWED BY THE MUCH SHORTER FOURTH PHASE WHICH IS A COMPRESSION PHASE WITH SUCTION OF THE AIR AND GASES.