US3749112A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Backpressure generating apparatus in an oil pressure operated circuit
Assignee: Honda Motor Co Ltd
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Filing: 1971-12-27
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Granted: 1973-07-31
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Expires: 1991-12-27
Abstract
Abstract A backpressure generating apparatus in an oil pressure-operated circuit in which an oil supply circuit and an oil return circuit are formed between an oil pressure source and an oil pressureoperated device and supply of oil to the device is regulated by a control valve interposed in the circuits; a no-load passage and a throttle passage are interposed in the oil return circuit in parallel with one another, such that the no-load passage is open during ordinary operation when the oil is at low pressure when the device is not operated, whereas when a high pressure is generated in the oil supply circuit during operation of the device, the no-load passage is closed by the action of the high pressure and the oil is by-passed through the throttle passage. An orifice is interposed in the oil supply circuit to heat the oil when the pressure is high due to cold operation conditions.
Inventors
- 👤 M Nishikawa
- 👤 A Akima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:11
CPC Classifications
F; F15; F15B; F15B11/00; F15B11/08; F15B2211/00; F15B2211/50; F15B2211/505; F15B2211/50509; F15B2211/50545; F15B2211/515; F15B2211/5157; F15B2211/5159; F15B2211/52; F15B2211/528; F15B2211/56; F15B2211/80; F15B2211/86; F15B2211/8609; Y; Y10; Y10T; Y10T137/00; Y10T137/2496; Y10T137/2544; Y10T137/2554; Y10T137/2559; Y10T137/2562
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
117 words
In a hydraulic circuit wherein liquid is supplied from a pressure source through a supply passage to a pressure-operative device and therefrom to a return passage, the flow of liquid to the pressure-operative device being controlled by a valve, an improvement comprising means defining a no-load passage and a throttle passage in the return passage in parallel with one another, and operating means for maintaining the no-load passage open during ordinary operation in the hydraulic circuit when the liquid is at low pressure for closing said no-load passage to bypass the liquid through said throttle passage when the liquid pressure is increased, and a throttle orifice in said supply passage between the pressure source and the valve.
Claim 2
Dependent Claim
117 words
In a hydraulic circuit wherein liquid is supplied from a pressure source through a supply passage to a pressure-operative device and therefrom to a return passage, the flow of liquid to the pressure-operative device being controlled by a valve, an improvement comprising means defining a no-load passage and a throttle passage in the return passage in parallel with one another, and operating means for maintaining the no-load passage open during ordinary operation in the hydraulic circuit when the liquid is at low pressure for closing said no-load passage to bypass the liquid through said throttle passage when the liquid pressure is increased, and a throttle orifice in said supply passage between the pressure source and the valve.
Claim 3
Dependent Claim
84 words
An improvement as claimed in claim 1 wherein said operating means comprises a valve member in said no-load passage, spring means urging said valve member to a normal position in which the no-load passage is open, and passage means connecting said valve member with the supply passage such that when the pressure of the liquid rises in the supply passage, the valve member will be displaced thereby against the opposition of the spring means to a position in which the no-load passage is closed.
Claim 4
Dependent Claim
28 words
An improvement as claimed in claim 2 wherein said throttle orifice is in the vicinity of the passage means which connects the supply passage and said valve member.
Claim 5
Dependent Claim
95 words
An improvement as claimed in claim 2 wherein said thrOttle passage includes an opening, a second valve member in said opening, second spring means acting on the second valve member to urge the same to a normal position in which said opening is blocked, and means for subjecting the second valve member to the pressure of the liquid in the return passage to displace the second valve member against the opposition of the second spring means to an operative position in which said opening is open when the first valve member closes the no-load passage.
Claim 6
Dependent Claim
33 words
An improvement as claimed in claim 4 wherein said second valve member includes a portion which forms a throttle channel in said opening when the second valve member is in its operative position.
Claim 7
Dependent Claim
39 words
An improvement as claimed in claim 5 wherein said portion of the second valve member includes at least one peripheral chamfer thereon to define said throttle channel in said opening when the second valve member is in operative position.
Claim 8
Dependent Claim
18 words
An improvement as claimed in claim 1 wherein said throttle passage is constituted by a single narrow opening.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |