US 3917437 A
A rotary piston engine, motor or pump having a rotor eccentrically mounted on a shaft and positioned within a housing to define a number of chambers, the rotor having a number of lobes equal to one less than the number of chambers and being rotated counter to the direction of rotation of the shaft to volumetrically displace a fluid in said chambers. A number of idler rollers are mounted in the housing at the points of intersection of the chambers in a position to engage the outer periphery of the rotor and to seal the chambers in the housing from each other. Vanes or brushes are provided in the housing to seal the outer surface of the idler rollers.
Description (OCR text may contain errors)
United States Patent Link SEAL FOR A ROTARY PISTON DEVICE Edwin A. Link, 317 S. Greenfield Ave., Waukesha, Wis. 53186 Filed: Mar. 18, 1974 Appl. N0.: 452,214
US. Cl. 415/125; 418/61 B Int. Cl F04c 27/00; FOlc 19/00 Field of Search 418/104, 125, 127, 128, 418/129, 61 B; 123/845 References Cited UNITED STATES PATENTS Primary Examiner-C. J. Husar Assistant ExaminerLouis J. Casaregola Attorney, Agent, or FirmRona1d E. Barry  ABSTRACT A rotary piston engine, motor or pump having a rotor eccentrically mounted on a shaft and positioned within a housing to define a number of chambers, the rotor having a number of lobes equal to one less than the number of chambers and being rotated counter to the direction of rotation of the shaft to volumetrically displace a fluid in said chambers. A number of idler rollers are mounted in the housing at the points of intersection of the chambers in a position to engage the outer periphery of the rotor and to seal the chambers in the housing from each other. Vanes or brushes are provided in the housing to seal the outer surface of the idler rollers.
8 Claims, 4 Drawing Figures US. Patent Nov. 4, 1975 Sheet 1 of2 3,917,437
2o, n "A? 32/16 14 25 Q Q R I 546/40 3+Lfl2 US. Patent Nov. 4, 1975 Sheet 2 of2 3,917,437
SEAL FOR A ROTARY PISTON DEVICE BACKGROUND OF THE INVENTION The present invention is an improvement on my earlier US. Pat. No. 3,340,855, issued on Sept. 12, 1967 and entitled Rotary Piston Engine. In my previous patent the engine was provided with a seal between flexible sections in the walls of the housing and the periphery of the rotor, the seal being biased by increasing the pressure in the space behind the flexible sections of the walls.
SUMMARY OF THE INVENTION The rotary engine of the present invention is provided with an improved seal between the rotor and the housing that has a longer life and can be more easily replaced. This seal is formed between removable idler rollers positioned in openings in the housing and the rotor. Each idler rotor is positioned to ride on the surface of the rotor and is sealed on the surface of the idler rollers. The brushes or vanes can be easily replaced whenever the seal becomes wom. A more positive seal is provided by intermeshing gear teeth located on the idler roller and on the surface of the rotor.
DRAWINGS FIG. 1 is a side view in section of a rotary piston engine showing the improved seal assembly of the invention;
FIG. 2 is a cross sectional view of the engine showing the flow path through the drive shaft;
FIG. 3 is a side view in section of a pump showing the seal assembly of the invention; and
FIG. 4 is a cross sectional view of the fluid flow path through the drive shaft.
DESCRIPTION OF THE INVENTION chambers from each other. These seal assembliesS provide a positive seal between the rotor and the housing which are subject to little or no wear but can be readily replaced, if necessary.
The Rotary Piston Engine (FIGS. 1 and 2) The rotary piston engine generally includes a stator or housing 12 and a rotor 14 mounted for rotation on a hub 16 which is eccentrically located on the shaft 17. In an engine of this type the hub 16 and shaft 17 rotate in a counterclockwise direction and the rotor 14 rotates in a clockwise direction. The motion of the rotor 14 within the housing 12 will volumetrically displace any gases in the chambers of the housing producing compression, expansion, exhaust and intake strokes with respect to each of the chambers.
The housing 12 includes a central chamber 18 and a pair of side plates 20 secured to each side of the member 18 by bolts 22. A number of chambers 24 are formed within the housing 12 between arcuate wall surfaces 26 provided in the member 18 and the inner wall surface 21 of the plates 20. Five chambers 24 are contemplated herein. However, the number of chambers can be varied depending on the number of rotor lobes as described hereinafter. A threaded opening 28 is provided through the wall of the member 18 into each of the chambers 24. A circular recess 32 is provided at the intersection of the arc uate wall surface 26 between each of the chambers 24. A pair of slots 34 are angularly disposed in the arcuate surface 32 with their axes intersecting at the center of the circle of revolution of the surface 32.
The drive shaft 17 is journalled in openings 38 in the walls 20 in a coaxial relation to the axis of the housing member 18 with the hub 16 located between the walls 20. The shaft 17 is provided with an inlet bore 40 at one end and an outlet or exhaust bore 41 at the other end.
The hub 16 is mounted on the shaft 17 to rotate eccentrically with respect to the shaft and is provided with a first or inlet passage 42 and a second or exhaust passage 44. The inlet passage 42 communicates with the chambers 24 through a slot 46. The passage 44 communicates with the chambers 24 through a slot 48. The peripheral length of the slots 46 and 48 are determined by length of time required for opening and closing of the passages 42 and 44, respectively.
The rotor 14 is symmetrical and includes four lobes 50. The peripheral surface 52 of each of the lobes 50 has a radius of curvature slightly smaller than the radius of curvature of the peripheral surface 26 of the chambers 24. An exhaust port 54 and an inlet port 56 are provided in two of the diametrically opposite lobes 50 of the rotor 14. The exhaust ports 54 are axially located in a position to communicate with the slots 48 in the hub 16 The inlet ports 56 are coaxially located in position 40 communicate with the slot 6 in the hub 16. The rotor 14 is mounted for rotation on the hub 16 and is rotated in the opposite direction to the direction of rotation of the shaft 17. The slots 46 and 48 are axially arranged on diametrically opposite ends of the hub 16 to open an inlet port 56 and an exhaust port 54 simultaneously. The length of time that the inlet port 56 and exhaust port 54 are opened will depend on the peripheral length of the slots 46 and 48, respectively.
Ignition of the combustible mixture in the chambers 24 is achieved by means of spark plugs 60 provided in the threaded openings 28 in the member 18. The spark plugs are timed to ignite the combustible mixture in a time sequence 1, 3, 5, 2, 4 as noted on FIG. 1 of the drawings.
Seal Assemblies 5 In accordance with the invention, the chambers 24 are sealed from each other by means of a number of seal assemblies 5. As seen in FIG. 1, five seal assemblies are provided in the housing to define five chambers or cavities 24 in the housing. Each seal assembly 5 in cludes an idler roller 62 mounted for rotation in the arcuate opening 32 in the member 18. Each of the idler rollers 62 is mounted for rotation on a pin 64 in a position to sealingly engage the outer peripheral surfaces 52 of the lobes 50.
The chambers 24 are sealed by means of intermeshing gear teeth 66 and 68 provided respectively on the peripheral surface 52 of the rotor and the surface of the idler rollers 62. In this regard the gear teeth 66 are provided on the outer surface of the lobes 50 to form a 3 continuous sea] surface. A corresponding gear tooth arrangement is provided by the gear teeth 68 on the outer periphery of the idler rollers 62. The rotor 14 is designed so that the teeth 66 on the rotor will continuously intermesh with the teeth 68 on each of the idler rollers 62.
Means are provided for sealing the spaces between the rotors 62 and the arcuate surfaces 32 in the member 18. Such means is in the form of a number of brushes or vanes 72 positioned in the recesses 34 in the member 18. Two brushes 72 are provided foreach idler roller 62. The brushes are biased into engagement with the surface of the gear teeth 68 on the rollers 62 by means of light springs 74 located at the inner ends of the bores 34. The brushes 72 are subject to wear as a result of the frictional engagement of the brushes with the ends of the gear teeth 68 but can be easily replaced by merely removing the idler rollers 62.
The Pump (FIGS. 3 and 4) The pump 80 is substantially identical to the engine in that the pump includes a stator or housing 82 and a rotor 84 which is mounted for rotation on a hub 86 eccentrically located on a shaft 87. The pump operates in the same manner as the engine 10 in that the rotor 84 rotates in a clockwise direction and the shaft 87 rotates in a counterclockwise direction producing a planetary motion between the shaft, rotor and housing. The motion of the rotor 84 within the housing 82 will volumetrically displace any fluid in the chambers in the housing as a result of the compression and expansion of the chambers.
The housing 82 is identical to the housing 12 for the engine and identical numbers have been used for the pump where the same parts have been previously identified in the engine.
The drive shaft 87 is provided with an inlet bore 90 at one end and an outlet or exhaust bore 91 at the other end. The hub 86 is eccentrically mounted on the shaft 87 and is provided with a first or inlet passage 92 and a second or exhaust passage 94. The inlet passage 92 communicates with the chambers 24 in the housing through slots 96 and the exhaust passage 94 communicates with the chambers 24 through slots 98.
The rotor 84 is symmetrical and is identical with the rotor 14 and identical numbers have been used where the rotors are identical. In this regard, it should be noted that the rotor 84 is provided with ports 100 between each of the lobes 50. Ports 100 act as both inlet and exhaust ports depending on the position of the slots 96 and 98 in the hub 86. Referring to FIG. 3, it should be' noted that two of the ports 100 are connected to the slots 96 and the other two ports 100 are connected to the slot 98. The two ports 100 connected to the slot 96 provide communication with the inlet bore 90 in the shaft 87 and the two ports 100 communicate with the slot 98 providing fluid communication with the discharge passage 91 in the shaft 87.
In a pump the shaft 87 will be driven counterclockwise as seen in FIG. 1 producing expansion and compression strokes in the chambers 24. Fluid will be drawn into the chambers 24 on the expansion strokes through the slot 96 and will be volumetrically displaced from the chambers 24 through the slot 98.
The seal assemblies 5, as seen in FIG. 3, are identical to the seal assemblies described for the engine in FIG. 1. Identical numbers have been used for identical parts.
The function of the seal assemblies is substantially the same as described above in that the idler rollers 62 sealingly engage the peripheral surface of the rotor lobes 50 to isolate the chambers 24 one from the other.
In operation, the rotor 84 will be rotating in a clockwise direction compressing fluid in the chambers 24 in a counterclockwise direction. As each rotor lobe 50 is moved into a'chamber 24 in a counterclockwise direction, the slot 98 will open a flow path from the chamber 24 under pressure through slot 98 to discharge port 91. Simultaneously, as a lobe 50 is retracted from a chamber 24, the slot 96 will provide communication with inlet bore in the hub 16.
It should be understood that sidewall seals are provided in both the pump and engine between the side plates, rotor and idler rollers as required. The sidewall seals are not shown since such seals are well known and do not form a part of the present invention.
It should also be noted that inlet passage means and exhaust passage means can be provided in the housing for admitting a combustible mixture into the chambers or for exhausting gases from the chambers.
1. A rotary piston device comprising a housing having a number of chambers,
a rotor having a number of lobes equal to one less than the number of chambers and a shaft journalled for rotation on the axis of the housing,
a series of gear teeth on the surface of each of said lobes,
a hub eccentrically mounted on the shaft, said rotor being mounted for rotation on said hub in the opposite direction of rotation of said shaft to volumetrically displace fluid in said chambers,
rotary seal members mounted in said housing between said chambers in a position to engage the surface of the lobes on said rotor,
and a series of gear teeth on the surface of said rotary seal members for sealingly engaging said gear teeth on said lobes.
2. The device according to claim 1 including ignition means in each of said chambers whereby said device operates as an engine.
3. The device according to claim 1 wherein said hub includes first passage means for admitting fluid through said shaft to said chambers and second passage means for discharging fluid from said chambers to'said shaft, said rotor including a passage between each pair of lobes, said passages being located in a common plane to provide communication between said chambers and said first and second passages in said hub.
4. The device according to claim 2 including inlet and exhaust ports in each lobe and one pair of diametrically oppositely located lobes of said rotor connected to the chambers, and wherein said hub includes a first passage providing communication for a combustible fuel mixture from said shaft to said inlet port,
and a second passage providing communication for exhaust gases from said exhaust port to said shaft.
5. The device according to claim 1 including seal means between said housing and said idler roller.
6. The device according to claim 5 wherein said seal means includes a brush positioned in said housing to bear against said roller for each idler roller and a means for biasing said brush against said roller.
7. A rotary piston pump comprising a housing having a number of chambers,
a drive shaft journalled for rotation in said housing,
a rotor having a number of lobes equal to one less than the number of chambers in said housing eccentrically mounted on said shaft,
passage means for admitting fluid to said chambers,
passage means for allowing fluid under pressure to discharge from said chambers,
means for rotating said drive shaft to drive said rotor in the opposite direction of rotation from said shaft, said rotor volumetrically displacing any fluid in said chambers,
roller means for sealingly engaging the surface of the rotor to isolate said chambers one from the other,
said roller means including a number of gear teeth on its outer surface and said rotor including a number of gear teeth on its outer surface to intermesh with the gear teeth on the roller surface,
a pair of brushes positioned in said housing in a position to engage said roller means and spring means for biasing said brushes into engagement with said roller means to seal the space between said roller means and said housing.
8. A rotary piston engine comprising:
a housing having a number of chambers,
ignition means in each of said chambers,
a drive shaft journalled for rotation in said housing,
a rotor having a number of lobes equal to one less than the number of chambers, said rotor being mounted on said shaft,
inlet passage means for admitting a combustible mixture into said chambers,
exhaust passage means connected to each of said chambers,
and a roller assembly between adjacent chambers to sealingly engage the surface of said rotor, said rol' ler assemblies each including an idler roller having a series of gear teeth on the outer surface and said rotor includes a series of gear teeth positioned to intermesh with said teeth on said rollers.