US3783713A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Kickdown arrangement for a hydraulic transmission
Assignee: Robert Bosch GmbH
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Filing: 1972-10-04
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Granted: 1974-01-08
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Expires: 1992-10-04
Abstract
Abstract A kickdown arrangement for the hydraulic transmission of a motorcar includes an electrohydraulic transducer with a throttle valve operated by an electromagnet, and a control valve controlled by pressure fluid from the throttle valve, and producing a hydraulic kickdown signal when a predetermined maximum control pressure is reached upon full depression of the gas pedal. Both valves receive fluid under pressure from the outlet of a pump driven by the motor which drives the transmission. A servo main valve connects the outlet of the pump with the hydraulic transmission, and is controlled by a control flow from the outlet of the throttle valve.
Inventors
- 👤 G Will
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:39
CPC Classifications
F; F16; F16H; F16H59/00; F16H59/14; F16H59/18; F16H59/20; F16H61/00; F16H61/02; F16H61/0202; F16H61/0251; F16H2061/026; F16H61/0262; F16H61/0265; F16H61/0267
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
200 words
Kickdown arrangement for a hydraulic transmission comprising a pump; a servo main valve connected between said pump and said transmission and being responsive to a pressure fluid control flow to provide shifting pressure for said transmission; an electrohydraulic transducer including an electromagnet, and a throttle valve operated by said electromagnet, said throttle valve having valve inlet means connected with said pump and valve outlet means connected with said servo main valve for supplying thereto a pressure fluid control flow; a control valve means having a first control inlet connected with said pump, a second control inlet connected with said valve outlet means, and a control outlet connected with said transmission; and electronic control means responsive to a kickdown pedal operation to energize said electromagnet to operate said throttle valve to move to a position increasing the pressure of said pressure fluid control flow until the control flow flows at the highest pressure through said valve outlet means into said second control inlet and moves said control valve to a position permitting flow of pressure fluid through said control outlet to said transmission as a hydraulic kickdown signal for actuating said transmission to shift down to the next lower speed stage.
Claim 2
Dependent Claim
200 words
Kickdown arrangement for a hydraulic transmission comprising a pump; a servo main valve connected between said pump and said transmission and being responsive to a pressure fluid control flow to provide shifting pressure for said transmission; an electrohydraulic transducer including an electromagnet, and a throttle valve operated by said electromagnet, said throttle valve having valve inlet means connected with said pump and valve outlet means connected with said servo main valve for supplying thereto a pressure fluid control flow; a control valve means having a first control inlet connected with said pump, a second control inlet connected with said valve outlet means, and a control outlet connected with said transmission; and electronic control means responsive to a kickdown pedal operation to energize said electromagnet to operate said throttle valve to move to a position increasing the pressure of said pressure fluid control flow until the control flow flows at the highest pressure through said valve outlet means into said second control inlet and moves said control valve to a position permitting flow of pressure fluid through said control outlet to said transmission as a hydraulic kickdown signal for actuating said transmission to shift down to the next lower speed stage.
Claim 3
Dependent Claim
93 words
Kickdown arrangement as claimed in claim 1 wherein said control valve means has a control valve slide piston having one end face forming a chamber in which said second control inlet is located so that the pressure of said control flow acts in said chamber to move said valve slide piston in one direction, said control valve means including a spring acting on the other end face of said valve slide piston and yielding to said maximum pressure so that said valve slide piston opens said control outlet and said first control inlet.
Claim 4
Dependent Claim
38 words
Kickdown arrangement as claimed in claim 1 wherein said throttle valve includes a throttle valve slide piston connected at one end with said electromagnet, and forming on the other end a chamber connected with said valve outlet means.
Claim 5
Dependent Claim
49 words
Kickdown arrangement as claimed in claim 1 comprising a motor for driving said transmission and said pump and being controlled by a pedal operated throttle; and wherein said electronic control meany include means responsive to the speed of said motor, and means responsive to the position of said throttle.
Claim 6
Dependent Claim
121 words
Kickdown arrangement as claimed in claim 1 wherein said control valve means has a control valve slide piston having one end face forming a chamber in which said second control inlet is located so that the pressure of said control flow acts in said chamber to movE said valve slide piston in one direction, said control valve means including a spring acting on the other end face of said valve slide piston and yielding to said maximum pressure so that said valve slide piston opens said control outlet and said first control inlet; wherein said throttle valve slide piston is connected at one end with said electromagnet, and forming at the other end a chamber connected with said valve outlet means.
References Cited (Backward Citations)
US3487725A
Cited
US3727487A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |