Patent US4627313A successfully refreshed from Google Patents.
US4627313A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for an infinitely variable transmission
Assignee: Subaru Corp
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Filing: 1985-01-29
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Granted: 1986-12-09
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Expires: 2005-01-29
Abstract
Abstract A control system for an infinitely variable belt-drive transmission which has a drive pulley having a hydraulically shiftable disc and a servo chamber for shifting the disc, a driven pulley having a hydraulically shiftable disc and a servo chamber for shifting the disc, and a belt engaged with both the pulleys. A hydraulic control circuit is provided for supplying oil to the servo chambers and for draining the servo chambers. A lubricating oil circuit is provided in the hydraulic control circuit for supplying lubricating oil to the drive pulley, and a passage is provided for supplying a part of the lubricating oil to the servo chamber of the drive pulley, thereby filling the servo chamber with the oil before the starting of transmission operation.
Inventors
- 👤 Yasuhito Sakai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:30
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/66; F16H61/662; F16H61/66254; F16H61/66263; Y; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19991
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
197 words
In a control system for an infinitely variable belt-drive transmission having a selector device including a drive range position and a neutral position, a drive pulley having a hydraulically shiftable disc and a servo chamber for shifting the disc, a driven pulley having a hydraulically shiftable disc and a servo chamber for shifting the disc, and a belt engaged with both the pulleys, a hydraulic control circuit for supplying oil to the servo chambers and for draining the servo chambers, the hydraulic control circuit being provided with a pressure regulator valve for providing a line pressure and a transmission ratio control valve for applying the line pressure to the servo chamber of the drive pulley, the improvement comprising: a lubricating oil circuit provided in the hydraulic control circuit for supplying lubricating oil to the drive and driven pulleys; a passage for supplying a part of the lubricating oil to the servo chamber of the drive pulley; a check valve provided in the passage for preventing the reverse flow of the lubricating oil; and a select position detecting valve for enabling the supply of the lubricating oil to the servo chamber at the selection of the neutral position.
Claim 2
Dependent Claim
197 words
In a control system for an infinitely variable belt-drive transmission having a selector device including a drive range position and a neutral position, a drive pulley having a hydraulically shiftable disc and a servo chamber for shifting the disc, a driven pulley having a hydraulically shiftable disc and a servo chamber for shifting the disc, and a belt engaged with both the pulleys, a hydraulic control circuit for supplying oil to the servo chambers and for draining the servo chambers, the hydraulic control circuit being provided with a pressure regulator valve for providing a line pressure and a transmission ratio control valve for applying the line pressure to the servo chamber of the drive pulley, the improvement comprising: a lubricating oil circuit provided in the hydraulic control circuit for supplying lubricating oil to the drive and driven pulleys; a passage for supplying a part of the lubricating oil to the servo chamber of the drive pulley; a check valve provided in the passage for preventing the reverse flow of the lubricating oil; and a select position detecting valve for enabling the supply of the lubricating oil to the servo chamber at the selection of the neutral position.
Claim 3
Dependent Claim
39 words
The control system according to claim 1 wherein the lubricating oil circuit is connected to a drain passage, and the select position detecting valve is provided for restricting the drain oil to raise the pressure of the lubricating oil.
Claim 4
Dependent Claim
20 words
The control system according to claim 1 further comprising means for restricting the drain from the transmission ratio control valve.
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) | 1989-12-08 | 1990-06-09 | 1990-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-08 | 1994-06-09 | 1994-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-08 | 1998-06-09 | 1998-12-09 | $7700.00 | Window Closed / Lapsed |