Patent US2885877A successfully refreshed from Google Patents.
US4129986A
Expired / Lapsed
US
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Method of and means for preventing thermal shock to a hydraulic motor in an open-loop hydraulic system
Assignee: Dynex Rivett Inc
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Filing: 1977-07-13
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Granted: 1978-12-19
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Expires: 1997-07-13
Abstract
Abstract Disclosed is a method of preventing thermal shock to a hydraulic motor in an open-loop hydraulic system. The method comprises the step of circulating warm oil through the motor when it is not in use. Preferably the method includes the further step of returning the warm oil to the tank after it has passed through the motor, and where appropriate it may also include the preliminary step of lowering the pressure of the warm oil before it is passed through the motor. The method is disclosed as applied to a vane motor, and means for carrying it out in that context are also disclosed.
Inventors
- 👤 Allan E. Heinrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 04:50
CPC Classifications
F; F04; F04C; F04C14/00; F04C14/28; F04C15/00; F04C15/0096
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
88 words
A method of preventing thermal shock to a hydraulic vane motor in an open-loop hydraulic system comprising a tank, a pump, at least one directional control valve, and the hydraulic vane motor, said hydraulic vane motor comprising a cam and motor housing containing a rotor mounted on a shaft, said housing having end cover portions, said method comprising the step of continuously circulating warm oil from a source of consistently warm oil through the end cover portions of the hydraulic vane motor when it is not in use.
Claim 2
Independent Claim
88 words
A method of preventing thermal shock to a hydraulic vane motor in an open-loop hydraulic system comprising a tank, a pump, at least one directional control valve, and the hydraulic vane motor, said hydraulic vane motor comprising a cam and motor housing containing a rotor mounted on a shaft, said housing having end cover portions, said method comprising the step of continuously circulating warm oil from a source of consistently warm oil through the end cover portions of the hydraulic vane motor when it is not in use.
Claim 3
Dependent Claim
27 words
A method as recited in claim 1 and including the further step of returning the warm oil to the tank after it has passed through the motor.
Claim 4
Dependent Claim
27 words
A method as recited in claim 1 and including the further step of lowering the pressure of the warm oil before it is passed through the motor.
Claim 5
Dependent Claim
20 words
A method as recited in claim 1 and including the further step of preventing back flow of the warm oil.
Claim 6
Dependent Claim
80 words
An open-loop hydraulic system comprising: (a) a tank, (b) a pump, (c) at least one directional control valve, (d) a hydraulic vane motor comprising a cam and motor housing containing a rotor mounted on a shaft, said housing having end cover portions and (e) means for continuously circulating warm oil from a source of consistently warm oil through the end cover portions of said hydraulic vane motor when it is not in use, thereby preventing thermal shock to said motor.
Claim 7
Dependent Claim
80 words
An open-loop hydraulic system comprising: (a) a tank, (b) a pump, (c) at least one directional control valve, (d) a hydraulic vane motor comprising a cam and motor housing containing a rotor mounted on a shaft, said housing having end cover portions and (e) means for continuously circulating warm oil from a source of consistently warm oil through the end cover portions of said hydraulic vane motor when it is not in use, thereby preventing thermal shock to said motor.
Claim 8
Dependent Claim
28 words
An open-loop hydraulic system as recited in claim 5 and further comprising means for returning the warm oil to said tank after it has passed through said motor.
Claim 9
Dependent Claim
28 words
An open-loop hydraulic system as recited in claim 5 and further comprising means for lowering the pressure of the warm oil before it is passed through said motor.
Claim 10
Dependent Claim
21 words
An open-loop hydraulic system as recited in claim 5 and further comprising means for preventing back flow of the warm oil.
Claim 11
Independent Claim
88 words
A method of preventing thermal shock to a hydraulic rotary motor in an open-loop hydraulic system comprising a tank, a pump, at least one directional control valve, and the hydraulic rotary motor, said hydraulic motor comprising a motor housing and a rotor disposed within said motor housing such that there is a small running clearance between said motor housing and said rotor said method comprising the step of continuously circulating warm oil from a source of consistently warm oil through said motor when it is not in use.
Claim 12
Independent Claim
88 words
A method of preventing thermal shock to a hydraulic rotary motor in an open-loop hydraulic system comprising a tank, a pump, at least one directional control valve, and the hydraulic rotary motor, said hydraulic motor comprising a motor housing and a rotor disposed within said motor housing such that there is a small running clearance between said motor housing and said rotor said method comprising the step of continuously circulating warm oil from a source of consistently warm oil through said motor when it is not in use.
Claim 13
Dependent Claim
82 words
An open-loop hydraulic system comprising: (a) a tank; (b) a pump; (c) at least one directional control valve; (d) a hydraulic rotary motor comprising a motor housing and a rotor disposed within said motor housing such that there is a small running clearance between said motor housing and said rotor; and (e) means for continuously circulating warm oil from a source of consistently warm oil through said hydraulic motor when it is not in use, thereby preventing thermal shock to said motor.
Claim 14
Dependent Claim
82 words
An open-loop hydraulic system comprising: (a) a tank; (b) a pump; (c) at least one directional control valve; (d) a hydraulic rotary motor comprising a motor housing and a rotor disposed within said motor housing such that there is a small running clearance between said motor housing and said rotor; and (e) means for continuously circulating warm oil from a source of consistently warm oil through said hydraulic motor when it is not in use, thereby preventing thermal shock to said motor.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-12-18 | 1982-06-19 | 1982-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-12-18 | 1986-06-19 | 1986-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-12-18 | 1990-06-19 | 1990-12-19 | $7700.00 | Window Closed / Lapsed |