Patent US3787147A successfully refreshed from Google Patents.
US3787147A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Two-stage air-hydraulic booster
Assignee: Owatonna Tool Co
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Filing: 1972-12-26
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Granted: 1974-01-22
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Expires: 1992-12-26
Abstract
Abstract A two-stage air-hydraulic booster having two pumping chambers, with one being a relatively large-volume, low-pressure chamber and the other a relatively small-volume, high-pressure chamber and with both chambers being formed, in part, by pumping structure carried by an air-operated piston. The ratio of the area of the air-operated piston to the area of the hydraulic cylinder for the large-volume, low-pressure chamber is relatively low whereby a large volume of fluid per inch of stroke is delivered to the system while the ratio of the area of the airoperated piston to the area of the high-pressure, small-volume chamber is high to deliver a small volume of fluid per inch of stroke of the air-operated piston. The structure provides for minimal consumption of operating air in both advancing the movable air-operated piston in a pumping stroke and in return of the air-operated piston to an initial position.
Inventors
- 👤 S Mcclocklin
- 👤 C Kostelecky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:51
CPC Classifications
F; F04; F04B; F04B9/00; F04B9/08; F04B9/12; F04B49/00; F04B49/18
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
92 words
A two-stage air-hydraulic booster having a cylinder with a movable piston therein, means including a first member on said piston defining a large-volume low-pressure hydraulic chamber, means including a second member on said piston defining a smallvolume high-pressure hydraulic chamber, air passage means for selectively directing air against a face of said movable piston to cause movement thereof from an initial position and force hydraulic fluid from said chambers, and second air passage means for selectively directing air against one of said members to return said movable piston to said initial position.
Claim 2
Dependent Claim
92 words
A two-stage air-hydraulic booster having a cylinder with a movable piston therein, means including a first member on said piston defining a large-volume low-pressure hydraulic chamber, means including a second member on said piston defining a smallvolume high-pressure hydraulic chamber, air passage means for selectively directing air against a face of said movable piston to cause movement thereof from an initial position and force hydraulic fluid from said chambers, and second air passage means for selectively directing air against one of said members to return said movable piston to said initial position.
Claim 3
Dependent Claim
49 words
A booster as defined in claim 1 wherein said first member is an annular sleeve extending from a face of the piston opposite said first mentioned face thereof, and said air for returning the piston to said initial position is directed against the exposed end of said annular sleeve.
Claim 4
Dependent Claim
57 words
A booster as defined in claim 2 wherein said means defining the small-volume chamber includes a block with a bore receiving the second member on the piston, said annular member being fitted onto said block to define said large-volume chamber therebetween, and a second bore in said block defining a hydraulic flow passage to said large-volume chamber.
Claim 5
Dependent Claim
52 words
A booster as defined in claim 3 including a hydraulic fluid reservoir, said reservoir being annular and having an inner wall surrounding said annular sleeve whereby said inner wall and said block define a chamber to receive said annular sleeve and the return air for returning the piston to said initial position.
Claim 6
Dependent Claim
65 words
A booster as defined in claim 1 including a control circuit with means for selectively directing air under pressure to either said face of the piston or against said first member, and said second air passage means including a quick exhaust valve responsive to air pressure caused by movement of said piston toward said initial position to connect said second air passage means to exhaust.
Claim 7
Dependent Claim
31 words
A booster as defined in claim 5 wherein said quick exhaust valve is responsive to the supply of air under pressure to said piston face to block said connection to exhaust.
Claim 8
Dependent Claim
71 words
A booster as defined in claim 5 wherein said control circuit includes a shiftable valve for selectively connecting said large-volume chamber to a hydraulic reservoir, and an air operated control piston associated with said valve whereby said valve shifts when the force thereagainst exceeds the force against said air operated control piston, and an air pressure regulator for controlling the pressure of the air acting against said air operated control Piston.
Claim 9
Dependent Claim
182 words
A two-stage air-hydraulic booster having a body with a cylinder with a movable piston therein, a cylindrical block extending from one end of the body toward said piston, an annular housing fitted to said end of the body to define a hydraulic reservoir and with the inner wall of said housing being spaced from the cylindrical block, an annular sleeve extending from one face of said piston and into the space between said block and said annular housing whereby a large-volume low-pressure chamber is defined within said sleeve, a first bore in said block and a plunger in said bore and extending from said one face of said movable piston whereby a small-volume high-pressure chamber is defined in said first bore, means for selectively directing air under pressure to said cylinder and against a face of said piston opposite said one face to move said piston from an initial position and reduce the size of said chambers, and means for selectively directing air under pressure against an exposed end of said annular sleeve to return said movable piston to said initial position.
Claim 10
Dependent Claim
182 words
A two-stage air-hydraulic booster having a body with a cylinder with a movable piston therein, a cylindrical block extending from one end of the body toward said piston, an annular housing fitted to said end of the body to define a hydraulic reservoir and with the inner wall of said housing being spaced from the cylindrical block, an annular sleeve extending from one face of said piston and into the space between said block and said annular housing whereby a large-volume low-pressure chamber is defined within said sleeve, a first bore in said block and a plunger in said bore and extending from said one face of said movable piston whereby a small-volume high-pressure chamber is defined in said first bore, means for selectively directing air under pressure to said cylinder and against a face of said piston opposite said one face to move said piston from an initial position and reduce the size of said chambers, and means for selectively directing air under pressure against an exposed end of said annular sleeve to return said movable piston to said initial position.
Claim 11
Dependent Claim
20 words
A booster as defined in claim 8 wherein said block has a second bore communicating with said large-volume low-pressure chamber.
Claim 12
Dependent Claim
46 words
A booster as defined in claim 8 including a hydraulic valve for connecting said large-volume chamber to either an outlet or reservoir, and means providing for shift of said valve to complete the connection to said reservoir when a predetermined pressure exists in said large-volume chamber.
Claim 13
Dependent Claim
38 words
A booster as defined in claim 10 including a control circuit having air and hydraulic components including said hydraulic valve, and said shifting means includes an air-operated control piston which acts to yieldably hold said valve against shifting.
Claim 14
Dependent Claim
28 words
A booster as defined in claim 11 including a pilot-operated check valve for preventing return flow to the reservoir upon loss of pressure air in said control circuit.
Claim 15
Dependent Claim
75 words
A booster as defined in claim 8 including an air exhaust passage connected to a passage leading to said cylinder and a quick exhaust valve positioned at the entrance to said exhaust passage and responsive to air under pressure being supplied to said cylinder to close the exhaust passage and responsive to reverse air flow as said movable piston returns to initial position to open said exhaust passage for quick return of said movable piston.
Claim 16
Dependent Claim
44 words
A booster as defined in claim 8 including a control circuit with air-operated components, a device operated by hydraulic fluid supplied from said chambers, and means for preventing return of hydraulic fluid to said chambers upon loss of pressure air in the control circuit.
Claim 17
Dependent Claim
183 words
A two-stage booster having a body with a cylinder with a movable piston therein, a cylindrical block extending from one end of the body toward said piston, an annular housing fitted to said end of the body to define a hydraulic reservoir and with the inner wall of said housing being spaced from the cylindrical block, an annular sleeve extending from one face of said piston and into the space between said block and said annular housing whereby a large-volume low-pressure chamber is defined within said sleeve, a first bore in said block and a plunger in said bore and extending from said one face of said movable piston whereby a small-volume high-pressure chamber is defined in said first bore, means for selectively directing control fluid under pressure to said cylinder and against a face of said piston opposite said one face to move said piston from an initial position and reduce the size of said chambers, and means for selectively directing control fluid under pressure against an exposed end of said annular sleeve to return said movable piston to said initial position.
Claim 18
Dependent Claim
183 words
A two-stage booster having a body with a cylinder with a movable piston therein, a cylindrical block extending from one end of the body toward said piston, an annular housing fitted to said end of the body to define a hydraulic reservoir and with the inner wall of said housing being spaced from the cylindrical block, an annular sleeve extending from one face of said piston and into the space between said block and said annular housing whereby a large-volume low-pressure chamber is defined within said sleeve, a first bore in said block and a plunger in said bore and extending from said one face of said movable piston whereby a small-volume high-pressure chamber is defined in said first bore, means for selectively directing control fluid under pressure to said cylinder and against a face of said piston opposite said one face to move said piston from an initial position and reduce the size of said chambers, and means for selectively directing control fluid under pressure against an exposed end of said annular sleeve to return said movable piston to said initial position.
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) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |