US3659481A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-hydraulic drive with regulated pressure
Assignee: Robert Bosch GmbH
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Filing: 1970-06-25
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Granted: 1972-05-02
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Expires: 1990-06-25
Abstract
Abstract A planetary hydraulic transmission is shifted between different stages by hydraulic operating means which receive pressure fluid whose pressure is adjusted by pressure regulating means which respond to control signals transmitted by an electronic control apparatus. The control signals represent a desired drive torque determined by the electronic control apparatus from signals received from means sensing various operational conditions of the drive motor of a car driven by the drive motor through the transmission. Since the regulated pressure is proportional to the drive torque, load peaks are prevented during shifting of the transmission.
Inventors
- 👤 Helmut Espenschied
- 👤 Georg Rothfuss
- 👤 Gerhard Will
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:51
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/0021; F16H61/02; F16H61/0202; F16H61/0251; F16H2061/0255
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
237 words
Electro-hydraulic drive with regulated pressure, comprising rotary motor means; transmission means driven by said motor means and having a plurality of stages, said transmission means including hydraulic operating means for shifting said transmission means between said stages; sensing means including first sensing elements for sensing said stages for producing a first sensing signal representing the operative stage at which said transmission means operates, and a second sensing element for sensing at least the speed of said motor means for producing a second sensing signal representing said speed of said motor means; electronic control apparatus controlled by said first and second sensing signals to compute the drive torque required for operation with the sensed operative stage at the sensed speed, and generating control signals representing said drive torque; pressure conduit means; a source of pressure fluid communicating with said pressure conduit means; primary pressure regulating means connected with said pressure conduit means, and controlled by said control signals of said control apparatus to adjust the pressure in said pressure conduit means in proportion to said drive torque; control conduit means connecting said pressure conduit means with said hydraulic operating means of said transmission means; and second pressure regulating means connected with said control conduit means and receiving control signals from said control apparatus to adjust the pressure in said control conduit means under the control of said control apparatus to the adjusted pressure in said pressure coNduit means.
Claim 2
Dependent Claim
237 words
Electro-hydraulic drive with regulated pressure, comprising rotary motor means; transmission means driven by said motor means and having a plurality of stages, said transmission means including hydraulic operating means for shifting said transmission means between said stages; sensing means including first sensing elements for sensing said stages for producing a first sensing signal representing the operative stage at which said transmission means operates, and a second sensing element for sensing at least the speed of said motor means for producing a second sensing signal representing said speed of said motor means; electronic control apparatus controlled by said first and second sensing signals to compute the drive torque required for operation with the sensed operative stage at the sensed speed, and generating control signals representing said drive torque; pressure conduit means; a source of pressure fluid communicating with said pressure conduit means; primary pressure regulating means connected with said pressure conduit means, and controlled by said control signals of said control apparatus to adjust the pressure in said pressure conduit means in proportion to said drive torque; control conduit means connecting said pressure conduit means with said hydraulic operating means of said transmission means; and second pressure regulating means connected with said control conduit means and receiving control signals from said control apparatus to adjust the pressure in said control conduit means under the control of said control apparatus to the adjusted pressure in said pressure coNduit means.
Claim 3
Dependent Claim
49 words
Electro-hydraulic drive as claimed in claim 1 wherein said primary pressure regulating means includes a plurality of pressure amplifying stages, the lowest amplifying stage being the most sensitive and including an electro-hydraulic converter for transforming the sequences of control signals received from said control apparatus into steady hydraulic pressure.
Claim 4
Dependent Claim
35 words
Electro-hydraulic drive as claimed in claim 1 wherein said secondary pressure regulating means include at least one electro-hydraulic converter for transforming the sequences of control signals received from said control apparatus into steady hydraulic pressure.
Claim 5
Dependent Claim
101 words
Electro-hydraulic drive as claimed in claim 1 wherein said hydraulic operating means include first hydraulic operating means associated with selected stages of said transmission means, and second hydraulic operating means associated with other stages of said transmission means; wherein said control conduit means include first control conduit means connected with said first hydraulic operating means and second control conduit means connected with said second hydraulic operating means; wherein said secondary pressure regulating means are connected with said first control conduit means; and comprising electro-magnetic valve means in said second control conduit means controlled by said control signals of said control apparatus.
Claim 6
Dependent Claim
75 words
Electro-hydraulic drive as claimed in claim 1 wherein said first sensing elements include a plurality of sensing contact means respectively associated with different stages of said transmission means; and comprising selector means including valve means having a valve slide carrying a contact means for selectively engaging said sensing contact means in displaced positions of said valve slide, said valve means selectively connecting said pressure conduit means with said control conduit means in said displaced positions.
Claim 7
Dependent Claim
99 words
Electro-hydraulic drive as claimed in claim 1 wherein said transmission means include a planetary transmission and brake bands associated with different stages of said transmission; wherein said hydraulic operating means include a plurality of hydraulic operating elements respectively operating said brake bands; and wherein said first sensing elements are respectively actuated by operated brake bands and control said control apparatus so that the same controls said secondary pressure regulating means and said hydraulic operating means so that the brake band of a stage of said transmission is relieved when the brake band of the following stage is fully operative.
Claim 8
Dependent Claim
15 words
Electro-hydraulic drive as claimed in claim 6 wherein said first sensing elements are sensing switches.
Claim 9
Dependent Claim
45 words
Electro-hydraulic drive as claimed in claim 6 wherein said first sensing elements are timing elements started at actuation of a brake band and producing a first sensing signal for said control apparatus after a predetermined time period for causing relieving of the respective brake band.
Claim 10
Dependent Claim
48 words
Electro-hydraulic drive as claimed in claim 1 wherein said transmission means includes a gear transmission and a hydraulic coupling; wherein said pressure conduit means is connected with said hydraulic coupling; and comprising a pressure regulator in said pressure conduit means for limiting the pressure in said hydraulic coupling.
Claim 11
Dependent Claim
198 words
Electro-hydraulic drive as claimed in claim 1 wherein said primary pressure regulating means includes a plurality of pressure amplifying stages, the lowest stage being the most sensitive and including an electro-hydraulic converter for transforming the sequences of control signals received from said control apparatus into steady hydraulic pressure; wherein the next higher amplifying stage includes a valve means having a spring-biassed valve slide and being connected with said pressure conduit and with said electro-hydraulic converter for adjusting the pressure in said pressure conduit means to be proportional to said steady hydraulic pressure; wherein said secondaRy pressure regulating means also includes an electro-hydraulic converter for transforming the sequences of control signals received from said control apparatus into steady hydraulic pressure; and wherein each of said electro-hydraulic converters includes electromagnetic coil means connected with said control apparatus, a magnetic core, a valve slide connected with said core, and a valve cylinder having a first outlet for fluid having said steady pressure, an inlet connected with said pressure conduit means, and a second outlet for discharging fluid to a low pressure space so that said steady pressure in said first outlet is less than the pressure in said pressure conduit means.
References Cited (Backward Citations)
US3158037A
Cited
US3397596A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-02 | 1975-11-01 | 1976-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-02 | 1979-11-01 | 1980-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-02 | 1983-11-01 | 1984-05-02 | $7700.00 | Window Closed / Lapsed |