US3590580A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic power apparatus
Assignee: Individual
•
Filing: 1970-03-13
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Granted: 1971-07-06
•
Expires: 1990-03-13
Abstract
Abstract Hydraulic apparatus to drive a number of fluid-actuated power components wherein a number of circuits, at least certain of which are provided with pumps of the variable flow type, are coupled to a common filter unit which not only filters the fluid flowing to the pump inlets but also assures that the pump inlet pressures will be at positive values to thereby prevent structural damage to the pumps, such as by cavitation, while at the same time, each pump is able to meet the fluid demands of its power component. A heat exchanger coupled to the circuits maintains the heat content of the fluid in the circuits within a safe temperature range. The apparatus is especially adapted for use with a vehicle having drive means, a power tool shiftably mounted on the vehicle, and power structure for shifting the power tool into any one of a number of operative positions.
Inventors
- 👤 Donald R Vaughan
- 👤 Carl J Falcon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 01:43
CPC Classifications
F; F15; F15B; F15B21/00; F15B21/04; F15B21/041; F15B1/00; F15B1/26; F15B21/042; F15B21/0423; F15B2211/00; F15B2211/60; F15B2211/61; F15B2211/611
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
181 words
Hydraulic apparatus comprising: a pair of hydraulic circuits; and a filter unit common to said circuits; each circuit including a fluid pump having a fluid inlet and a fluid outlet, a fluidactuated power device having a fluid inlet and a fluid outlet, first conduit means coupling said outlet of the pump to said inlet of the device, second conduit means coupling said outlet of the device with said inlet of the pump, said filter unit including filter means across said second conduit means for filtering the fluid flowing to said pump inlet, a fluid reservoir, and eductor means coupled to said reservoir and to said second conduit means between said device and said filter means for drawing fluid into said second conduit means from said reservoir responsive to the fluid pressure at said filter means, and third conduit means placing said reservoir in fluid communication with said second conduit means at a location on the latter between said eductoR means and said device, whereby fluid in the circuit may return to the reservoir when the fluid demand of said pump decreases.
Claim 2
Dependent Claim
181 words
Hydraulic apparatus comprising: a pair of hydraulic circuits; and a filter unit common to said circuits; each circuit including a fluid pump having a fluid inlet and a fluid outlet, a fluidactuated power device having a fluid inlet and a fluid outlet, first conduit means coupling said outlet of the pump to said inlet of the device, second conduit means coupling said outlet of the device with said inlet of the pump, said filter unit including filter means across said second conduit means for filtering the fluid flowing to said pump inlet, a fluid reservoir, and eductor means coupled to said reservoir and to said second conduit means between said device and said filter means for drawing fluid into said second conduit means from said reservoir responsive to the fluid pressure at said filter means, and third conduit means placing said reservoir in fluid communication with said second conduit means at a location on the latter between said eductoR means and said device, whereby fluid in the circuit may return to the reservoir when the fluid demand of said pump decreases.
Claim 3
Dependent Claim
43 words
Hydraulic apparatus as set forth in claim 1, wherein said eductor means includes a check valve disposed to prevent fluid flow from said reservoir to said second conduit means until a predetermined fluid flow rate has been established in said second conduit means.
Claim 4
Dependent Claim
61 words
Hydraulic apparatus as set forth in claim 1, wherein the fluid pump of one of said circuits has actuatable means for varying the volume rate of flow of fluid from said output thereof, and means responsive to the fluid pressure in the first conduit means of the other circuit for actuating said varying means of the pump of said one circuit.
Claim 5
Dependent Claim
32 words
Hydraulic apparatus as set forth in claim 1, wherein is provided a heat exchanger in said third conduit means for changing the heat content of the fluid flowing therethrough to said reservoir.
Claim 6
Dependent Claim
25 words
Hydraulic apparatus as set forth in claim 1, wherein is provided a relief valve in said third conduit means to limit the fluid flow therethrough.
Claim 7
Dependent Claim
145 words
Hydraulic apparatus comprising: a fluid pump having a fluid inlet and a fluid outlet; a fluid-actuated power device having a fluid inlet and a fluid outlet; a first conduit connecting said outlet of the pump to said inlet of said device; a second conduit connecting said outlet of the device with said inlet of the pump; a filter across said second conduit to filter the fluid passing therethrough toward said pump; a fluid reservoir; an eductor including a suction element across said second conduit; a third conduit placing said suction element in fluid communication with said reservoir; a check valve in said third conduit and disposed to permit fluid flow only from said reservoir to said suction element; and a fourth conduit placing said reservoir in fluid communication with said second conduit at a location between said suction element and said outlet of the device.
Claim 8
Dependent Claim
145 words
Hydraulic apparatus comprising: a fluid pump having a fluid inlet and a fluid outlet; a fluid-actuated power device having a fluid inlet and a fluid outlet; a first conduit connecting said outlet of the pump to said inlet of said device; a second conduit connecting said outlet of the device with said inlet of the pump; a filter across said second conduit to filter the fluid passing therethrough toward said pump; a fluid reservoir; an eductor including a suction element across said second conduit; a third conduit placing said suction element in fluid communication with said reservoir; a check valve in said third conduit and disposed to permit fluid flow only from said reservoir to said suction element; and a fourth conduit placing said reservoir in fluid communication with said second conduit at a location between said suction element and said outlet of the device.
Claim 9
Dependent Claim
24 words
Hydraulic apparatus as set forth in claim 6, wherein is provided a relief valve in said fourth conduit to limit the fluid flow therethrough.
References Cited (Backward Citations)
US2251664A
Cited
US3370423A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-05 | 1975-01-04 | 1975-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-05 | 1979-01-04 | 1979-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-05 | 1983-01-04 | 1983-07-06 | $7700.00 | Window Closed / Lapsed |