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US3693503A Expired / Lapsed US ⏱️ 0.0 years remaining

Hydrostatic transmission control with hydraulic follow-up

Assignee: International Motors LLC
•
Filing: 1970-12-14
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Granted: 1972-09-26
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Expires: 1990-12-14
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Abstract

Abstract A hydraulic follow-up for use with a hydraulic system placed between a rotating input member and a rotating output member. The hydraulic system is a hydrostatic transmission for driving a tractor, and comprises a hydrostatic pump and a hydrostatic motor driven by the pump. When the hydrostatic pump is angularly shifted with respect to the input member, the shifting is controlled by the hydraulic follow-up, which also shifts the motor in relation to the output member.

Inventors

  • 👤 Charles A L Ruhl
  • 👤 Edward Meyer
  • 👤 Probir K Chatterjea

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 00:15
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/38; F16H61/40; F16H61/42; B; B62; B62D; B62D11/00; B62D11/02; B62D11/06; B62D11/10; B62D11/14; B62D11/18; B62D11/183; F16H61/423; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86493; Y10T137/86574; Y10T137/8667; Y10T137/86694; Y10T137/8671

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 161 words
Servo mechanism with hydraulic follow-up comprising: a follower valve having a source of high and low pressure; hydraulic mechanism connected thereto, causing the valve to take a position corresponding to the angular position of said mechanism and to provide an actual-speed output at a pressure between high and low corresponding to said position; a second valve (19) having a source of high (26) and low pressure; manual mechanism (18) connected to the second valve, causing said valve to take a position corresponding to the angular position of the manual mechanism and to provide a desired-speed output at a pressure between high and low corresponding to the just said position; and comparator means (31 or 80) connected in the outputs of said valves effective to control the positions of the hydraulic mechanism and follower valve to a point at which the outputs reach an actual-speed desired-speed pressure balance indicative of correspondence in Angular position between the manual mechanism and the hydraulic mechanism.
Claim 2
Dependent Claim 161 words
Servo mechanism with hydraulic follow-up comprising: a follower valve having a source of high and low pressure; hydraulic mechanism connected thereto, causing the valve to take a position corresponding to the angular position of said mechanism and to provide an actual-speed output at a pressure between high and low corresponding to said position; a second valve (19) having a source of high (26) and low pressure; manual mechanism (18) connected to the second valve, causing said valve to take a position corresponding to the angular position of the manual mechanism and to provide a desired-speed output at a pressure between high and low corresponding to the just said position; and comparator means (31 or 80) connected in the outputs of said valves effective to control the positions of the hydraulic mechanism and follower valve to a point at which the outputs reach an actual-speed desired-speed pressure balance indicative of correspondence in Angular position between the manual mechanism and the hydraulic mechanism.

References Cited (Backward Citations)

US2268000A Cited
US2613502A Cited
US3543515A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1975-09-26 1976-03-27 1976-09-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1979-09-26 1980-03-27 1980-09-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1983-09-26 1984-03-27 1984-09-26 $7700.00 Window Closed / Lapsed

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