US3890684A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making a hydraulic jack
Assignee: Individual
•
Filing: 1974-05-09
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Granted: 1975-06-24
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Expires: 1994-05-09
Abstract
Abstract A weight lifting hydraulic jack has a supporting base consisting of a single block with the pump cylinder cast integrally with the base. A vertical assembly consists of a central vertical hydraulic cylinder in which a lifting ram reciprocates and the hydraulic cylinder is concentrically mounted within a cylindrical housing and these two parts are cast as a single unit. Free ends of the cylinder and housing are given cast shapes precisely fitting cast receptacles in the base. Self threading bolts extend through cast holes in the base into cast holes in the vertical assembly holding the entire jack together. After a conventional ram is fastened in the hydraulic cylinder and a conventional pump piston and actuating linkage is pinned in place on the base by a single screw, the jack is ready for operation.
Inventors
- 👤 Erven Tallman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:03
CPC Classifications
B; B66; B66F; B66F3/00; B66F3/24; B66F3/25; B66F3/42; B23; B23P; B23P15/00; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/49236
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
195 words
A method for forming and assembling a weight lifting jack for reception of a conventional hydraulic ram and a conventional pump piston and pump actuating mechanism therefor, and for attachment of a pump release valve screw, said method comprising forming a base unit by casting therein concentric radially spaced recesses having annular walls and circumferentially spaced fastening holes extending from the bottom upwardly, casting a pump housing on the base unit with a downwardly open pump cylinder bore therein, forming a relief valve bore in a communicating relationship with the exterior and said pump cylinder bore, and forming hydraulic passages between said recesses and said pump cylinder bore, forming a vertical unit by casting concentric radially spaced inner and outer cylinders whereby to provide a ram chamber in the inner cylinder and a reservoir between the inner and outer cylinders closed by material of the casting at the outer end, cast forming inner ends of the cylinders to fit into the respective inner and outer recesses, casting circumferentially spaced anchoring recesses in respective alignment with said anchoring holes, and finally fastening said units together with self tapping bolts extending between said holes and said recesses.
Claim 2
Independent Claim
195 words
A method for forming and assembling a weight lifting jack for reception of a conventional hydraulic ram and a conventional pump piston and pump actuating mechanism therefor, and for attachment of a pump release valve screw, said method comprising forming a base unit by casting therein concentric radially spaced recesses having annular walls and circumferentially spaced fastening holes extending from the bottom upwardly, casting a pump housing on the base unit with a downwardly open pump cylinder bore therein, forming a relief valve bore in a communicating relationship with the exterior and said pump cylinder bore, and forming hydraulic passages between said recesses and said pump cylinder bore, forming a vertical unit by casting concentric radially spaced inner and outer cylinders whereby to provide a ram chamber in the inner cylinder and a reservoir between the inner and outer cylinders closed by material of the casting at the outer end, cast forming inner ends of the cylinders to fit into the respective inner and outer recesses, casting circumferentially spaced anchoring recesses in respective alignment with said anchoring holes, and finally fastening said units together with self tapping bolts extending between said holes and said recesses.
Claim 3
Dependent Claim
55 words
A method as in claim 1 including cast forming a release valve bore in the base unit from an exterior location to a location in engagement with said pump cylinder bore, forming a release valve element with self tapping threads adjacent the inner end and injecting said release valve element into said release valve bore.
Claim 4
Dependent Claim
57 words
A method as in claim 1 including making said casting of an aluminum material, making the wall of the inner cylinder relatively thin in proportion to the performance requirement of the jack, and casting reinforcing ribs in the reservoir between the inner and outer cylinders whereby to strengthen the inner cylinder in proportion to said performance requirement.
Claim 5
Dependent Claim
30 words
A method as in claim 1 including forming annular recesses at respective areas of engagement of said cylinders with said recesses and inserting resilient O ring seals in said recesses.
Claim 6
Dependent Claim
66 words
A method as in claim 1 including forming a shoulder in said cylindrical chamber at the outer end, forming a snap ring recess in said cylindrical chamber at the outer end further out than said shoulder, placing an O ring seal means on said shoulder and locking said seal means and the ram in position by insertion of a snap ring in said snap ring recess.
Claim 7
Dependent Claim
64 words
A method as in claim 1 including forming the pump cylinder bore by the initial casting operation to extend from inside said base through the outer end of said pump housing, and forming an O ring recess in the wall of said pump cylinder bore adjacent the outer end of said pump housing for reception of an O ring to seal said pump piston.
Claim 8
Dependent Claim
56 words
A method as in claim 1 including casting slot means having spaced parallel walls in the base for reception of the pump actuating mechanism and fastening the pump actuating mechanism to said base by use of a single self tapping bolt extending into a recess in the base and through the walls of said slot means.
Claim 9
Dependent Claim
31 words
A method as in claim 1 including forming all said hydraulic passages from a location within said concentric recess in a direction radially outwardly into engagement with others of said passages.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-23 | 1978-12-23 | 1979-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-23 | 1982-12-23 | 1983-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-23 | 1986-12-23 | 1987-06-24 | $7700.00 | Window Closed / Lapsed |