US3722337A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluid-actuated punch press with workpiece stripper
Assignee: WHITNEY CORP W
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Filing: 1970-12-31
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Granted: 1973-03-27
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Expires: 1990-12-31
Abstract
Abstract The press includes a fluid-operated actuator for reciprocating a punch and also includes a stripper which is partially telescoped into the cylinder of the actuator so as to be forced downwardly into clamping engagement with the workpiece by the same pressure fluid admitted into the cylinder to retract the punch upwardly out of the workpiece. In addition, the actuator and a spring disposed within the cylinder coact to cause the stripper to clamp the workpiece during punching and to release the workpiece after the punch has been retracted out of the workpiece.
Inventors
- 👤 T Brolund
- 👤 W Kuchar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:44
CPC Classifications
B; B21; B21D; B21D45/00; B21D45/003; B21D45/006; B21D28/00; B21D28/24; B21D28/26; Y; Y10; Y10T; Y10T83/00; Y10T83/202; Y10T83/2092; Y10T83/2096; Y10T83/2135; Y10T83/215; Y10T83/2153; Y10T83/2155; Y10T83/2159; Y10T83/748; Y10T83/7487; Y10T83/7553; Y10T83/869; Y10T83/8821; Y10T83/8858
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
260 words
A punch press comprising a support, a double-acting, fluidoperated actuator on said support and comprising a cylinder with a piston slidable downwardly and upwardly therein in response to the admission of pressure fluid alternately into upper and lower chambers in the upper and lower ends of said cylinder, a ram projecting downwardly from said piston and guided for up and down sliding by said cylinder, and a punch supported on the lower end of said ram and cooperable with an underlying die on said support to perforate an intervening workpiece on the downward stroke of said ram, the improvement in said press comprising, a stripper telescoped slidably over said ram and having a lower end spaced upwardly from the workpiece when the ram is fully retracted, a mechanical spring acting on said stripper and operable during the downward stroke of said ram first to move said stripper downwardly with the ram and into engagement with said workpiece and thereafter to permit continued advancement of said ram relative to said stripper to drive said punch through said workpiece, the upper end portion of said stripper being telescoped slidably into the lower end of said cylinder and being disposed within said lower chamber whereby pressure fluid admitted into said lower chamber during initial upward retraction of said ram exerts a downward force on the stripper to keep the latter in clamping engagement with said workpiece, and an abutment on said ram and engageable with said stripper upon continued upward retraction of the ram thereby to retract the stripper upwardly from the workpiece.
Claim 2
Dependent Claim
260 words
A punch press comprising a support, a double-acting, fluidoperated actuator on said support and comprising a cylinder with a piston slidable downwardly and upwardly therein in response to the admission of pressure fluid alternately into upper and lower chambers in the upper and lower ends of said cylinder, a ram projecting downwardly from said piston and guided for up and down sliding by said cylinder, and a punch supported on the lower end of said ram and cooperable with an underlying die on said support to perforate an intervening workpiece on the downward stroke of said ram, the improvement in said press comprising, a stripper telescoped slidably over said ram and having a lower end spaced upwardly from the workpiece when the ram is fully retracted, a mechanical spring acting on said stripper and operable during the downward stroke of said ram first to move said stripper downwardly with the ram and into engagement with said workpiece and thereafter to permit continued advancement of said ram relative to said stripper to drive said punch through said workpiece, the upper end portion of said stripper being telescoped slidably into the lower end of said cylinder and being disposed within said lower chamber whereby pressure fluid admitted into said lower chamber during initial upward retraction of said ram exerts a downward force on the stripper to keep the latter in clamping engagement with said workpiece, and an abutment on said ram and engageable with said stripper upon continued upward retraction of the ram thereby to retract the stripper upwardly from the workpiece.
Claim 3
Dependent Claim
62 words
A punch press as defined in claim 1 in which said spring comprises a coiled compression spring telescoped over said ram and urging said stripper downwardly and away from said piston, said spring being compressed when said stripper engages said workpiece during the downward stroke of said ram and yielding to permit continued downward advancement of the ram relative to the stripper.
Claim 4
Dependent Claim
39 words
A punch press as defined in claim 1 further including means disposed within said cylinder and sealing said stripper to the outer surface of said ram to the inner surface of said cylinder to keep said lower chamber fluid-tight.
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) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |