CA1233145A - Volumetric displacement fluid machine - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

This machine can serve as a compressor or motor and, more specifically combines a compressor and a motor to constitute an internal combustion engine with compressed air injection. A toothed rotor is rotatable in a fluid displacement chamber and in sealing contact with a sealing rotor having peripheral cavities for receiving the teeth of the toothed rotor. Both rotors are axially curved, so as to better resist differential axial thrust exerted on the same and, therefore, maintaining better sealing contact.
The teeth of the toothed rotor are generally of a hemi-spherical shape to facilitate the provision of effective sealing segments. When used as an internal combustion engine, a combined fuel injection and ignition device is provided enclosed within a sleeve rotatable within the engine housing, the sleeve having a lateral opening which can be made to selectively register with one of two housing passages opening in two adjacent fluid displacement chambers, with the result that the engine can be reversed by the simple rotation of the ignition device enclosing sleeve.

Description

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FIELD OF THE I~VENTION
. Th~ present invention relates to a rotary voLumetr.ic displacement fluid machine to b used as fluid motors and pumps and including internal combustion engines~
BACKGROUND OF THE IMVENTIOM-. Applicant's-prior U~S. Paten~ N 3~.20~j~06 da.~ed August 31, 1965 and prior Canadian Patent 780,666 dated March 19, 1968~ disclose rotary eng~nes o~ the type in which a toothed rotor rotates in sealing contac~ w~bh a sealing rotor and with its teeth meshing with ca-~rities at the periphery of the sealing rotor. It has ~een found difficult to provide effective sealing between the two rotors ard also between the toothed rotor and the surface of its chamber~
It has been found that this was mainly due to the fact that the two rotors were of cylindrical shape, as were their enclosing chambers, resultin~ in difficult 'o seal corner wall portions and also a relative axial disp~acement of the two rotors upon differen~ial axial presssure exerted thereon, especially in the compressor uni~ where axial pressure is exerted on the sealing rotor upon discharge of the compressed air from one end of the compressor unit.
It is therefore the general object of the present inventiorl to provide a machine of the character --- described, which will overcome the ab4ve--mentione*~dis~
advantage of the rotary machin~ described in applicant's - prior patents.
Another object of the present ir.vention is to provide a machine of the character described, which, when used as an internal combus~ion engine, incorporates a novel and efEective combined uel injector and ignition unit.
Another object of the present invention is to provlde an engine of the character descrlbedl in wh:l.ch the fuel injectlon and ignitlon unit 1~ arran~d so as to ~..~ ..
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inJect fuel in either one of two adjacent combustion chambers in such a manner as to reverse the engine rotational direction.
Another object of the present invention resides in the provision of an engine of the character described, in which the volumetric efficiency is made optimum for a given machine size, in both the compressor and the motor mode.
Another object of the present invention is to provide a machine of tne character described, which, when used as an internal combustion engine, has means for efficient sweeping of the burnt gases.
SUMMARY OF THE INVENTION
The rotary volumetric displacement fluid machine of the present invention comprises a housing, two parallel shafts journalled in the housing, a sealing rotor and a toothed rotor keyed to the respective shafts, both rotors having sealingly-contacting peripheral surfaces, means causing rotation of the rotors in opposite directions, peripheral surfaces being cross-sectionally circular and axially curved, the sealing rotor curvature being reversed to and mating with the toothed rotor curvature, the teeth of the toothed rotor having a matching fit with cavities at the periphery of the sealing rotor. Preferably, the teeth - of the toothed rotor have a generally half-spherical shape.
When the machine is used as a fluid compressor, the peripheral surface of the toothed rotor is concave for maximum volumetric efficiencyO When the machine is used as a motor, the peripheral surface of the toothed rotor is longitudinally ~ convex for maximum output.torque. One o the inlet and outlet ports of the fluid displacement chamber .~s located in the sealing rotor cavity and forms a passage i~ the seal-ing .rotor,wh:lch is normal~y closed by an end wall of the chamber, to have a timed valving action with a reglster:lncJ
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opening in said chamber and wall. ~ e sealing rotor of the motor unit preferably has a diameter so as to rotate twice the speed of the toothed rotor and, t~e~efore, has twice the cavities as there are teeth of the to~3thed ro~or, so as to increase the working stroke of the toothed. rotor.
BRIEF DESCRIPTICN OF THE DRAWINGS
__ In the annexed drawings:
Figure 1 is a longitudinal section of a rotary internal combustion engine made in accordance with the principles of the invention; and 1 ~ Figure 2 is a partial cross-section taken along line 2-~ of Figure 1.
The machin~ as described comprises, as in applicant's prior above--noted patents, a compressor unit, generally indic-ated at l, a compressed air storage chamber 2~ and a motor unit 3, all housed within a housing 4 through which extend parallel shats including a central sealin~ rotor carrying shaft 5 and equally angularly spaced too~hed rotc)r-carr~ing shafts 6. In the example shown, the cert.ral shaft 5 ls surrounde~ by thxee satellite shafts 6, as in the arrangement shown in Figur~ 5 in-applicant's prior V S. pat3nt. In the example shown, the satellite shafts 6 rotate at the same speed but in opposite direction from centraL shaft 5 through gearing 7.
Referring to the motor unitl3, a sealing ~rotor 8' ~
is keyed to cenkral shaft 5 along wit~ bushiny 9~ This sealing rotor 8 has a peripheral surface 10, which is circular in cross-section, but which is longitudinally curved, namely: which is concave. Two diametrically-opposed tooth-receiving cavitie~ lL are formed at the peripheral surface10 of the sealln~ rotor 8, these cavit:Les baing of generally part spherical shape. ~ toothed rotor ~.~ is ~ceyed to aach of the sa-tellita sha~ts 6; it has a per~pheral surEaca 1:3 ~.~233~

hich is of cross-sectionally circular shape but of longi-tudinally curved shape, namely: convex shape to sealingly fit the longitudinally concave shape of the peripheral surface 10 of the sealing rotor 8, so as to be in sealing and rolling contact therewith. Two diametrically-opposed generally semi spherical ~eeth 14 are screwed within the rotor 12 and these are designed to successively have a sealing fit with the cavities 11 of th~ sealing rotor ~ during counterrotation of these two rotors. Teeth 14 carry sealing segments 15,of cur~ed shape, as shown in Figure 1. The housing 4 defines a sealing rotor chamber 16 for the motor unit and as many fluid displacement chambers 17, called combustion chambers 17r for the motor unit. Paxtition walls l8, 18'in housing 4 define the end walls oE the chambers 16, 17 and are in sliding contact with the ends of the two rotors 8 and 12. Combustion chamber 17 has an outlet or exhaust port 19 diametrically opposite the sealing rotor 8 with respect to the satellite shaf~ 6. Chamber 17 has also inlet ports for the admission of pressurized air. These ports are indicated at 20; they directly open within the sealing rotor cavities 11 from longitudinally opposite ends of said cavities, andj.once..for each ro~tion of.the..sealing rotor, they come in register with end wall openings 21, so as to form a timed valving action to admit the pressurized air within the combustion chamber at the proper time during rotation of the toothed rotor. Each end wall opening 21 can be adjustably throttled by a throttling disc 22, the angular position of which is adjustable through its gear teeth 23 which mesh with pinions 24 carried by the shaft 25 of a throttling lever 26~ this arrangement being similar to that described in applicant's prior U.S. patent in relation with thro~tling dlsc 10~,110, as shown in Figures 9 and 8, respect-ively, and also in E'igure 13. A comb.ined fuel injection and J" ' Y

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ignition device, generally indicated at 27, extends radially of the central shaft 5 ;n the housiny wall portion separating each pair of adjacent combustlon chambers 17. The device 27 includes a central, cylindrical nozzle 28 having a radially i.nner nozzle orifice adjustably closed by a needle val.ve 29, centrally extending throuyh the nozzle 28 and axially adjustable by rotation of its threaded radially outer portion 30 in the threaded head 31 of the nozzle body through the means of a lever arm 32 secured to the needle valve 29. Fuel under pressure from a suitable fuel pump is supplied to the nozzle 28 through hose 33 and passage 34. Nozzle 2~ is fixedly retained within a cylin~xical_s-eeve 35 with the interposition of heat-insulating bushing 36, this bushing extending short of the radially inner portion of the nozzle 28, so as to form an annular clearance in which is located an electric resistance wire ~7, which is directl~ wound around the nozzle radially inner portion, being supplied with electricity through a cable 38 at one end, the ~ther end of the resistance wire 37 being grounded at 39. Sleeve 35 is completely closed at its radially inner end by closure wall 40, but has a lateral opening 41 for the discharge of the pre-heated and vaporized fuel. Sleeve 35 is axially rotatable within the bore of the housing 4 in which it is located by means of an operating lever 42, so that its lateral opening 41 can be selectively registered with one or the other of two oppositely-extending passages 43 made in the portion o~ the housing wall between the two adjacent combustion chambers 17. An O-ring 44 seals the sleeve 35. In the rotated position of the sleeve 351 shown in Figure 2, the toothed rotor 12 is caused to rotate in accordance with arrows A in cloc}cwise direction. The rotors are shown in -their dead center position. As soon as the bottom tooth 14 starts -to rotate clockwise, the inlet port ~L2~3~5 indicated in dotted lines in Figure ~ at, 2~ ~ecome un-covered downstream from the tooth and f~eds col~pressed air behind the tooth as long as the cavity 11 remains in com-~unication with the combustion chamber. ~umerals lla and 20a show a rotated position of cavity ll and port 20. When the seal-ng segments 15,oE the bottom tooth move passed the passage 43, this passage becomes filled with pressurized air and then pre-heated fuel is admitted within-said a~r! resulting i~
ignition and combust~on of the fuel behind the tooth, resultir.g in the pressure stroke which lasts until the tooth ha~ reached almost the topmost head center position, whereupon the burnt gases are exhausted. It is obvious that rot~tion of the sleeves 35 through half a turn will cause registering of their lateral opening 41 with the passage 43 of the adjacent combustion chan~ers, causi,ng rotation of the rotor in the opposite direction.
Referring again to Figure 2, any burn~ gas remain-ing in ~he right-hand portion o the combustion chamber 17 can be swept away through the exhaust por~ 19 hy air under pressure supplied through a bleeding passage 45 made in the housing 4 and in communication~with the pre~,surized air conduit 46, which connects the pressurized air, storage chamber

2 disposed intermediate the compressor unit l and the motor unit with the inlet port 20 at the o~ter end~~f~'~h~ motc¢~
unit. This conduit 46 is preferably~provided with heat~
radiating fins 47. The amount of ai~ fed through passage 45 can be manually adjusted by needle valve 48 operated by lever 49O Adjacent combustion chambers 17 are sealed rom each other by sealing segments 50 pressed against the peri-pheral surface of the rotor by air under pressure suppliedby passages 51.

The compressor unit 1 includes a sealing rotor 52 keyed Oll the central shaft 5 through b~shing 53 ancl common to three too-thed rotors 54 angularly, aqually spaced ~ ~3~L~L~
around the central shaft 5, being ke~ed to the satellite shafts 6, which are arranged concentr~c with central shaft 5. As for the engine rotors, the sealing rotor 52 and toothed rotors 54 are of circular crosss-sectional shape, but are curved axially of the rotor. More specifically, the perlpheral surface 55 of the sealing rotor ls conve.~ axlally of the rotor and ~its the longitudinally concave peripheral surface 56 of the toothf~d rotor 54 to have a sealing rolling contact therewith. The teeth~57 of the toothed rGtar 54 are of ~.enerally hemi-spherlcal shape. In the example shown, there are two diametrically-opposed'teeth 57 ~nd e-?.ch adapted to engage a matching peripheral cavity 58 in the sealing rotor 52. There are two diametrically-opposed cavities 58, the two rotors being deslgned to rotate in inverse direction at the same peripheral speed~ The end faces of the two rotors 52, 54 are flat and in sliding contact with the partition walls 59, 60 of the housing 4. The housing also defines a fluid displacement cross-sectionally circular chamber and a rotor chamber in the same manner as for motor unit 3 and having a surface in ,slldirtg contact with the teeth 57 and the longitudinally convex surface of rhe sealing rotor 52. The compressor unit 1 has a main air inlet port 61, which~is diametrically opposed to the seal~ng rotor 52 with respect to ~he satellite shaft 5 and whlch is provided with butterfly valve~ 62 ~otatably adjus~able.', .;
by a lever 63.
Means are'~provided to cool`the ~oothed ro~ors 12 of the motor unit 3 by means of a compressed air suppl~
and to inject this air into the CQmpreSSOr u.nit~. Each satellite shaft 6 is of hollow constructlon and opens at one end within the casing 64 of a ventilating fan.
the hub 65 o~ which is secured to the central shat 5.

Each toothed .rotor 12, :lncluding its teeth 14, ls of hollow construction and is provicled with a central baffle 66, 8 ~

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causing the ai~ supplied by the fan ~nd which circulat~s through the hollow shaft to enter the toothed rotor 12 through shaft opening 67; then move around the surface of the hollow rotor to be dischar~ed throuyh sha~t opening 68. The air is then divided into two streams by ~e longitudinal partition walls 69 within the saJ;ell~te shaft 60 each s~ream issuing at the peripheral surface of the sealing rotor 52 of the compresso~ unit 1, contiguous to each tooth 57 a~ each end of the tooth and on both sides thereof. Therefore, they are provided,for each tootX,two air discharge openings 70. ~ valving tu~e 71 is inserted into the hollow satellite sha~t 6 and has a ciosed outer end 72 provided with an operating lever 73, which rotates the valving tube 71 with respect to the shaft ~ to two ;mgularly-adjusted posi~ion-sin order to selectively register o~enings 74 of the valving tube 71 with either the pair of openings 70 on one side of the tooth S7 or the pair of such openlngs 70 on the other side of the pair. This ar-angement is designed to arrange air injection always on the downstream side of the tooth, depending on the direction o~ rotation of the compressor.
The air compressed by the toothed rotor is discharged through outlet port 7~, which forms a passage within the body of the sealing rotor 52, opening within cavity 58 and at the end face of the sealing rotor to register at the end of the compression stroke, with an opening 76 màde in partition wall 60. Therefoxe, the air discharge~ betwe~n the two partition walls 60 and 18, which define the compressed air stora~e chamber 2. Because the rotor rotates with respect to opening 76, there is a valving action defined to discharge the compressed air Erom the compre~sing tookhed rotor 54 at an end of the compression ~troke. If desired, a valvlng Aisc 77 may be keyed to khe cenkral shaft 5 to rokate wi-~h a 3L2;3 3~S

sliding fit against the partition wall G0; but ~his valve disc is not essential.
The starter for the engine, not shown, is preferably arranged to drive on0 of the satellite shafts 6. ~lther one o~ the sha~ts 5 or 6 can be used as an output shaft. The central shaft 5 also drives the fuel injection and the lubricating oil pump,schema-tically shown at 78.
If desired, the main air inlet port 61 can be directly ~onnected to the output of the air fan, which can be an air turbine. The butterfly valves 62 are made to c]ose the air inlet port 61 for starting the engine. Thus, during engine starting by a starter, the air is solely su~plied by the fan through the satellite shaft openings 70, on the downstream side of the teeth 57. The air is compressed and a gradual pressure build=up is effected in the storage chamber 2. When the necessary pressure has been attained, fuel injection is initiated~ Once the motor is running, the butterfiy valve~ 62 are opened to supply the full amount of air to the engine. Regulation of the motor speed is achieved by regulating the throttling disc 22 in conjunction with the needle valve 29 of the fuel injection and ignition device 27. The engine can be slowed down and reversed in its direction of rotation by rotating sleeve 35 by means of its operating lever 42 in conjunction with the change of position of the valving tube 71 by means of its lever ~ .

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed, are defined as follows:

1. A rotary volumetric displacement fluid machine comprising: a housing, two parallel shafts journalled in said housing, a sealing rotor and a toothed rotor keyed to the respective shafts; both rotors having sealingly-contacting peripheral surfaces, means causing notation of said rotors in opposite directions, said peripheral surfaces being cross-sectionally circular and axiallycurved, the sealing rotor curvature reversed relative to and mating with the toothed rotor curvature, said toothed rotor having at least two teeth, said sealing rotor having at least one peripheral cavity, of a shape to receive said teeth with a matching fit, said housing defining intersecting and com-municating chambers in which said rotors are located, the chamber housing said toothed rotor having surfaces conformed to have a sliding fit with said teeth, said housing having fluid inlet and outlet ports for admitting into and expel-ling fluid from the chamber housing said toothed rotor.
2. A machine as defined in claim 1, wherein said chambers have end walls with which the ends of said rotors have a sliding fit, one of said ports being located in said sealing rotor, opening in said at least one cavity and form-ing a passage extending through said sealing rotor to an end thereof to have a timed valving action with an opening made in the contiguous chamber end wall.
3. A machine as defined in claim 2, wherein said toothed rotor and its carrying shaft are hollow and in communication with each other, and further including means to circulate a fluid through said hollow shaft and through said hollow toothed rotor.

4. A machine as claimed in claim 2, wherein the shaft carrying sasid toothed rotor is hollow and communicates with the chamber containing the toothed rotor through openings at the peripheral surface of the toothed rotor contiguous to each tooth and downstream therefrom relative to the rotational direction of said toothed rotor, and means to supply fluid under pressure to said toothed rotor shaft, in order to discharge said fluid into said toothed rotor chamber through said openings.
5. A machine as defined in claim 2, said machine constituting a fluid compressor, the peripheral surface of said toothed rotor and sealing rotor being longitudinally concave and convex, respectively, the port located in said at least one cavity constituting a fluid outlet port.
7. A machine as defined in claim 2, wherein said machine is a pressure fluid-operated motor, the peripheral surfaces of said toothed rotor and of said sealing rotor being longitudinally convex and concave, respectively, the port loc-ated in said at least one cavity being a fluid inlet port, the outlet port located at a portion of said toothed rotor chamber, which is diametrically opposite to the sealing rotor relative to the shaft axis of the toothed rotor.
8. A machine as defined in claim 7, further including a fuel injection and igniting device carried in saidhousing, said device including an injector nozzle sur-rounded by an electric resistance element engaged in a sleeve having a lateral discharge opening for communication with a housing passage opening in the toothed rotor chamber angularly close to said sealing rotor to discharge a heated and vaporized fuel into said passage in timing relation with said toothed rotor rotation.

9. A machine as claimed in calim 8, wherein said sealing rotor has a diameter, so as to rotate at twice the speed of the toothed rotor and has twice as many cavities as there are teeth on said toothed rotor. i 10. A machine as defined in claim 8, wherein there are at least two toothed rotors and associated chambers arranged around and concentric with a common sealing rotor and its associated chamber, with one said fuel injection and igniting.
device located between two toothed rotor chambers, there being for each said device two oppositely-directed housing passages opening in the two toothed rotor chambers, said sleeve being axially rotatable to selectively register its lateral discharge opening with one or the other of the two housing passages, so as to change the rotational direction of said toothed rotor.
11. A machine as defined in claim 10, further including means to admit pressurized air into the toothed rotor chamber in the downstream portion of the latter chamber to complete sweeping of the burnt combustion gases through said outlet port.
12. A machine as defined in claim 8, further including means to inject pressurized air directly onto said injector nozzle to supply fresh air into said housing passage.
13. The combination of a gas compressor with a fuel-operated motor, comprising a housing having a?

compressor housing section, a motor housing section and an intermediate cornpressed gas chamber between the compressor housing section and the motor housing section; two parallel shafts journalled in said housing; a motor sealing rotor and a compressor sealing rotor, keyed to one shaft and located in said motor housing section and compressor housing section, respectively; a motor toothed rotor and a compressor toothed rotor keyed to the other shaft and located in said motor housing section and compressor housing section, respectively; each sealing rotor coacting with a toothed rotor; both coacting rotors having sealingly-contacting peripheral surfaces, means causing rotation of said shafts in opposite directions, said peripheral surfaces being cross-sectionally circular and axially curved, each toothed rotor having at least two teeth, each sealing rotor having at least one peripheral cavity of a shape to receive said teeth with a matching fit, each housing section defining intersecting and communicating chambers in which the respective rotors are located, the chambers, housing the toothed rotors, having surfaces formed to have a sliding fit with said teeth, each housing section having gas inlet and outlet ports for admitting into and expelling gas from the chamber, housing the toothed rotor, each chamber having end walls with which the ends of the rotor housed therein has a sliding fit, one of said ports being located in said sealing rotor, opening in said at least one cavity and forming a passage extending through said seal-ing rotor to an end thereof to have a time-valving action with an opening made in the contiguous chamber end wall;
the peripheral surfaces of the compressor toothed rotor and of the compressor sealing rotor being longitudinally concave and convex, respectively, the port located at the said at least one cavity of said compressor sealing rotor constituting a gas outlet port, the peripheral surfaces of the motor toothed rotor and of the motor sealing rotor being longitudinally convex and concave, respectively, the port located in said at least one cavity of the motor sealing rotor being a gas inlet port, the outlet port of the motor housing section being located in a portion ?f the motor toothed rotor chamber, which is diametrically opposite to the motor sealing rotor relative to the axis of the shaft carrying said two toothed rotors; said motor housing section further including a fuel injection and igniting device, said device including an injector nozzle surrounded by an electric resistance element engaged in a sleeve having a lateral discharge opening for communication with a housing passage opening in the motor toothed rotor chamber angularly closed to said motor sealing rotor to discharge a heated and vaporized fuel into said passage in timing relation with said motor toothed rotor rotation.