US3887310A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic pump/motor with hydrostatically balanced rotors
Assignee: Individual
•
Filing: 1973-07-02
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Granted: 1975-06-03
•
Expires: 1993-07-02
Abstract
Abstract A power rotor and idler rotor having intermeshing teeth are rotatably mounted within bushings in a housing on offset axes. The idler rotor is smaller in diameter than the power rotor and rotates substantially within the circumference of the power rotor teeth. The teeth of the two rotors mesh in one portion of their circumference and are separated by a crescent baffle in the diametrically opposed portion of their circumference. The power rotor teeth make sealing contact between the outer surface of the crescent baffle and between its bores and the adjacent end surfaces of the working chamber within which the teeth rotate and act to pump fluid from an inlet port in the housing to an outlet port therein or to be driven by fluid under pressure moving from one port to the other. The idler rotor teeth make sealing contact between the inner surface of the crescent baffle and the diametrically opposite part of its bore section and between the idler rotor boss sleeve bearing and the adjacent end surfaces of the working chamber within which the idler rotor teeth rotate. The meshing portion of the idler rotor teeth and power rotor teeth are shaped in the form of matching concave-convex surfaces having different radii of curvature to provide for rolling contact thereinbetween. Hydraulic pressure chambers are formed between the hub of the idler rotor and its bearing to balance the axial, radial and tilting hydraulic pressures thereon so that the idler rotor tends to float friction free in its annular cavity. A duct conveys pressurized fluid from the high pressure end of the power rotor to its other end or to a shoulder to counterbalance the hydraulic working load and to produce a selfcompensating wear zero clearance fit within all end surfaces of working parts.
Inventors
- 👤 Karol Gerber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:42
CPC Classifications
F; F04; F04C; F04C2/00; F04C2/08; F04C2/10; F04C2/101; F04C15/00; F04C15/0042
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
210 words
In a pump/motor unit having a housing with a rotor chamber, a liquid inlet at one side of the chamber and a liquid outlet at the other side of the chamber, said inlet and outlet providing for passage of liquid through said chamber, power and idler rotors in said chambers, said rotors having intedigitable teeth, bearings upon which said rotors turn, the improvement for hydraulically balanciNg hydrostatic pressure on the idler rotor and comprising pressure chamber means between the idler rotor and its bearing, said pressure chamber means comprising narrow grooves, the bearing surfaces between said grooves being wider than the grooves and defining hydraulic film spaces fed by said grooves and duct means from the rotor chamber to said grooves to conduct pressurized liquid to said pressure chamber means and counter-balance the hydrostatic pressure of said liquid on the idler rotor, said idler rotor having a cylindrical hub, said pressure chamber means comprising a plurality of such narrow grooves disposed radially in one axial end of said hub and running out at the inner surface of the hub and a like plurality of such narrow grooves extending axially along the inside of said hub and running out at the end of the hub and intercommunicating with said radial grooves.
Claim 2
Dependent Claim
210 words
In a pump/motor unit having a housing with a rotor chamber, a liquid inlet at one side of the chamber and a liquid outlet at the other side of the chamber, said inlet and outlet providing for passage of liquid through said chamber, power and idler rotors in said chambers, said rotors having intedigitable teeth, bearings upon which said rotors turn, the improvement for hydraulically balanciNg hydrostatic pressure on the idler rotor and comprising pressure chamber means between the idler rotor and its bearing, said pressure chamber means comprising narrow grooves, the bearing surfaces between said grooves being wider than the grooves and defining hydraulic film spaces fed by said grooves and duct means from the rotor chamber to said grooves to conduct pressurized liquid to said pressure chamber means and counter-balance the hydrostatic pressure of said liquid on the idler rotor, said idler rotor having a cylindrical hub, said pressure chamber means comprising a plurality of such narrow grooves disposed radially in one axial end of said hub and running out at the inner surface of the hub and a like plurality of such narrow grooves extending axially along the inside of said hub and running out at the end of the hub and intercommunicating with said radial grooves.
Claim 3
Dependent Claim
210 words
In a pump/motor unit having a housing with a rotor chamber, a liquid inlet at one side of the chamber and a liquid outlet at the other side of the chamber, said inlet and outlet providing for passage of liquid through said chamber, power and idler rotors in said chambers, said rotors having intedigitable teeth, bearings upon which said rotors turn, the improvement for hydraulically balanciNg hydrostatic pressure on the idler rotor and comprising pressure chamber means between the idler rotor and its bearing, said pressure chamber means comprising narrow grooves, the bearing surfaces between said grooves being wider than the grooves and defining hydraulic film spaces fed by said grooves and duct means from the rotor chamber to said grooves to conduct pressurized liquid to said pressure chamber means and counter-balance the hydrostatic pressure of said liquid on the idler rotor, said idler rotor having a cylindrical hub, said pressure chamber means comprising a plurality of such narrow grooves disposed radially in one axial end of said hub and running out at the inner surface of the hub and a like plurality of such narrow grooves extending axially along the inside of said hub and running out at the end of the hub and intercommunicating with said radial grooves.
Claim 4
Dependent Claim
210 words
In a pump/motor unit having a housing with a rotor chamber, a liquid inlet at one side of the chamber and a liquid outlet at the other side of the chamber, said inlet and outlet providing for passage of liquid through said chamber, power and idler rotors in said chambers, said rotors having intedigitable teeth, bearings upon which said rotors turn, the improvement for hydraulically balanciNg hydrostatic pressure on the idler rotor and comprising pressure chamber means between the idler rotor and its bearing, said pressure chamber means comprising narrow grooves, the bearing surfaces between said grooves being wider than the grooves and defining hydraulic film spaces fed by said grooves and duct means from the rotor chamber to said grooves to conduct pressurized liquid to said pressure chamber means and counter-balance the hydrostatic pressure of said liquid on the idler rotor, said idler rotor having a cylindrical hub, said pressure chamber means comprising a plurality of such narrow grooves disposed radially in one axial end of said hub and running out at the inner surface of the hub and a like plurality of such narrow grooves extending axially along the inside of said hub and running out at the end of the hub and intercommunicating with said radial grooves.
Claim 5
Dependent Claim
34 words
The improvement defined in claim 1 wherein said idler rotor is crown gear shaped with a hub and axially extending crown teeth, said pressure chamber means being formed between said hub and its bearing.
Claim 6
Dependent Claim
47 words
The improvement defined in claim 1 wherein said idler rotor is spur gear shaped with a hub and radially extending spur teeth, said pressure chamber means being formed between the hub and its bearing, said duct means comprising radial openings through the hub and between the teeth.
Claim 7
Dependent Claim
20 words
The improvement as defined in claim 1 in which said idler rotor has an over-all thin wall sleeve body configuration.
Claim 8
Dependent Claim
30 words
The improvement defined in claim 1 in which said idler rotor has a hub with axially extending teeth and a sleeve beneath said teeth from which said teeth extend radially.
Claim 9
Dependent Claim
172 words
In a pump/motor unit having a housing with a rotor chamber, a liquid inlet at one side of the chamber and a liquid outlet at the other side of the chamber, said inlet and outlet providing for passage of liquid through said chamber, power and idler rotors in said chamber, said rotors having interdigitable teeth, bearings upon which said rotors turn, the improvement for hydraulically balancing hydrostatic pressure on the idler rotor and comprising pressure chamber means between the idler rotor and its bearing, said pressure chamber means comprising narrow grooves, the bearing surfaces between said grooves being wider than the grooves and defining hydraulic film spaces fed by said grooves and duct means from the rotor chamber to said grooves to conduct pressurized liquid to said pressure chamber means and counter-balance the hydrostatic pressure of said liquid on the idler rotor, the narrow grooves of said pressure chamber means comprising a plurality of narrow axial grooves in said bearing and a narrow circumferential groove in said bearing interconnecting said axial grooves.
Claim 10
Dependent Claim
172 words
In a pump/motor unit having a housing with a rotor chamber, a liquid inlet at one side of the chamber and a liquid outlet at the other side of the chamber, said inlet and outlet providing for passage of liquid through said chamber, power and idler rotors in said chamber, said rotors having interdigitable teeth, bearings upon which said rotors turn, the improvement for hydraulically balancing hydrostatic pressure on the idler rotor and comprising pressure chamber means between the idler rotor and its bearing, said pressure chamber means comprising narrow grooves, the bearing surfaces between said grooves being wider than the grooves and defining hydraulic film spaces fed by said grooves and duct means from the rotor chamber to said grooves to conduct pressurized liquid to said pressure chamber means and counter-balance the hydrostatic pressure of said liquid on the idler rotor, the narrow grooves of said pressure chamber means comprising a plurality of narrow axial grooves in said bearing and a narrow circumferential groove in said bearing interconnecting said axial grooves.
Claim 11
Dependent Claim
309 words
In a hydraulic pump/motor unit having a housing with a rotor chamber, a liquid inlet port at one side of the chamber and a liquid outlet port at the other side of the chamber, said inlet and outlet ports providing for passage of liquid through said chamber, power and idler rotors in said chamber, said rotors having interdigitable teeth, bearings on which said rotors turn, and means for applying hydraulic pressure to one axial end of said power rotor to counter-balance axial pressures thereon caused by the pressure of the liquid on the power rotor, the improvement comprising preload means for applying a mechanical preload pressure to said one axial end of said power rotor to provide an axial pressure thereon in the absence of said hydraulic pressure, said preload means for applying said hydraulic pressure to one axial end of said power rotor comprising a balancing disk seated within said housing and positioned adjacent to said one axial end of said power rotor, a low friction bearing surface on said balancing disk for bearing against said one axial end of said power rotor to convey axial pressure thereto, and duct means for applying hydraulic pressure from the rotor chamber to the side of said balancing disk away from said power rotor, and wheRein said means for applying a mechanical preload pressure comprises a preload disk seated within said housing and positioned to bear against the balancing disk, an O-ring between said disks and in radial contact with the seat in the housing for the balancing disk, thus to seal said hydraulic pressure, said O-ring being of resilient material and a preload screw threaded within said housing and positioned to bear against said preload disk to press the O-ring against said balancing disk, thereby providing adjustable mechanical pressure on said balancing disk in the absence of said hydraulic pressure.
Claim 12
Dependent Claim
309 words
In a hydraulic pump/motor unit having a housing with a rotor chamber, a liquid inlet port at one side of the chamber and a liquid outlet port at the other side of the chamber, said inlet and outlet ports providing for passage of liquid through said chamber, power and idler rotors in said chamber, said rotors having interdigitable teeth, bearings on which said rotors turn, and means for applying hydraulic pressure to one axial end of said power rotor to counter-balance axial pressures thereon caused by the pressure of the liquid on the power rotor, the improvement comprising preload means for applying a mechanical preload pressure to said one axial end of said power rotor to provide an axial pressure thereon in the absence of said hydraulic pressure, said preload means for applying said hydraulic pressure to one axial end of said power rotor comprising a balancing disk seated within said housing and positioned adjacent to said one axial end of said power rotor, a low friction bearing surface on said balancing disk for bearing against said one axial end of said power rotor to convey axial pressure thereto, and duct means for applying hydraulic pressure from the rotor chamber to the side of said balancing disk away from said power rotor, and wheRein said means for applying a mechanical preload pressure comprises a preload disk seated within said housing and positioned to bear against the balancing disk, an O-ring between said disks and in radial contact with the seat in the housing for the balancing disk, thus to seal said hydraulic pressure, said O-ring being of resilient material and a preload screw threaded within said housing and positioned to bear against said preload disk to press the O-ring against said balancing disk, thereby providing adjustable mechanical pressure on said balancing disk in the absence of said hydraulic pressure.
Claim 13
Dependent Claim
139 words
In a hydraulic pump/motor unit having a housing with a rotor chamber, a liquid inlet at one side of the chamber and a liquid outlet at the other side of the chamber, said inlet and outlet providing for passage of liquid through said chamber, power and idler rotors in said chamber, said rotors having a plurality of teeth which mesh simultaneously, the valleys between teeth on one rotor being only slightly larger circumferentially than the teeth on the other rotor, the improvement for reducing friction between the rotor teeth wherein the meshing portion of said teeth are shaped as matching concave-convex surfaces, the radius of said concave surface being only slightly larger than the radius of said convex surface, said concave-convex surfaces providing rolling contact in the meshing portion of said teeth, thereby reducing the friction between the teeth.
Claim 14
Dependent Claim
139 words
In a hydraulic pump/motor unit having a housing with a rotor chamber, a liquid inlet at one side of the chamber and a liquid outlet at the other side of the chamber, said inlet and outlet providing for passage of liquid through said chamber, power and idler rotors in said chamber, said rotors having a plurality of teeth which mesh simultaneously, the valleys between teeth on one rotor being only slightly larger circumferentially than the teeth on the other rotor, the improvement for reducing friction between the rotor teeth wherein the meshing portion of said teeth are shaped as matching concave-convex surfaces, the radius of said concave surface being only slightly larger than the radius of said convex surface, said concave-convex surfaces providing rolling contact in the meshing portion of said teeth, thereby reducing the friction between the teeth.
Claim 15
Dependent Claim
30 words
The improvement defined in claim 8 wherein the side meshing portions of the power rotor teeth are convex and the side meshing portions of the idler rotor teeth are concave.
Claim 16
Dependent Claim
229 words
In a pump/motor unit having a housing with a rotor chamber, a liquid outlet at one side of the chamber and a liquid outlet at the other side of the chamber, said inlet and outlet providing for passage of liquid through said chamber, power and idler rotors in said chamber, said rotors having interdigitable teeth, bearings upon which said rotors turn, the improvement for hydraulically balancing hydrostatic pressure on the idler rotor and comprising pressure chamber means between the idler rotor and its bearing, said pressure chamber means comprising narrow grooves, the bearing surfaces between said grooves being wider than the grooves and defining hydraulic film spaces fed by said grooves and duct means from the rotor chamber to said grooves to conduct pressurized liquid to said pressure chamber means and counter-balance the hydrostatic pressure of said liquid on the idler rotor, and the improvement for reducing friction between the power and idler rotor teeth wherein a plurality of such teeth mesh simultaneously, the valleys between teeth of one rotor being only slightly longer circumferentially than the teeth on the other rotor and the meshing portion of said teeth are shaped as matching concave-convex surfaces, the radius of said concave surface being only slightly larger than the radius of said convex surface to provide rolling contact in the meshing portion of said teeth, thereby reducing the friction between teeth.
Claim 17
Dependent Claim
229 words
In a pump/motor unit having a housing with a rotor chamber, a liquid outlet at one side of the chamber and a liquid outlet at the other side of the chamber, said inlet and outlet providing for passage of liquid through said chamber, power and idler rotors in said chamber, said rotors having interdigitable teeth, bearings upon which said rotors turn, the improvement for hydraulically balancing hydrostatic pressure on the idler rotor and comprising pressure chamber means between the idler rotor and its bearing, said pressure chamber means comprising narrow grooves, the bearing surfaces between said grooves being wider than the grooves and defining hydraulic film spaces fed by said grooves and duct means from the rotor chamber to said grooves to conduct pressurized liquid to said pressure chamber means and counter-balance the hydrostatic pressure of said liquid on the idler rotor, and the improvement for reducing friction between the power and idler rotor teeth wherein a plurality of such teeth mesh simultaneously, the valleys between teeth of one rotor being only slightly longer circumferentially than the teeth on the other rotor and the meshing portion of said teeth are shaped as matching concave-convex surfaces, the radius of said concave surface being only slightly larger than the radius of said convex surface to provide rolling contact in the meshing portion of said teeth, thereby reducing the friction between teeth.
Claim 18
Dependent Claim
30 words
The improvement defined in claim 10 wherein the side meshing portion of the power rotor teeth are convex and the side meshing portions of the idler rotor teeth are concave.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |