US3678792A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Metal plate shears
Assignee: Individual
•
Filing: 1970-12-15
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Granted: 1972-07-25
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Expires: 1990-12-15
Abstract
Abstract A metal plate shears for cutting large sheets of metal in which four rollers are hydraulically slid between a guide way and four inclined ramps so as to force a cutting blade downward through a large metal plate. A high leverage hydraulic clamp serves to hold the plate in place during the shearing operation. The edge of the lightweight cutting blade is kept straight by a unique truss arrangement mounted on the side of the blade.
Inventors
- 👤 Frank Dvorak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:36
CPC Classifications
B; B23; B23D; B23D15/00; B23D15/12; B23D15/14; B23D33/00; B23D33/08; Y; Y10; Y10T; Y10T83/00; Y10T83/748; Y10T83/7487; Y10T83/7533; Y10T83/7547; Y10T83/869; Y10T83/8776; Y10T83/8785; Y10T83/8821; Y10T83/8841; Y10T83/8853; Y10T83/8854; Y10T83/8858; Y10T83/8866; Y10T83/929; Y10T83/9457; Y10T83/9473; Y10T83/9478
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
91 words
A hydraulic metal plate shears comprising in combination: a frame a fixed shearing blade a movable shearing blade, mounted for sliding movement in said frame; ramp means on said movable blade, a set of roller assemblies positioned to roll between said frame and said ramp means so as to move said movable blade past said fixed blade in a shearing relationship; connector bars connected to said rollers; and hydraulic means on said frame operable to move said connector bars so as to move said rollers between the frame and ramp means.
Claim 2
Dependent Claim
91 words
A hydraulic metal plate shears comprising in combination: a frame a fixed shearing blade a movable shearing blade, mounted for sliding movement in said frame; ramp means on said movable blade, a set of roller assemblies positioned to roll between said frame and said ramp means so as to move said movable blade past said fixed blade in a shearing relationship; connector bars connected to said rollers; and hydraulic means on said frame operable to move said connector bars so as to move said rollers between the frame and ramp means.
Claim 3
Dependent Claim
43 words
The apparatus of claim 1 including first spring means on said frame operable to urge said movable blade away from said fixed blade and second spring means on said frame operable to urge said rollers out from between said frame and ramp means.
Claim 4
Dependent Claim
27 words
The apparatus of claim 2 including a reinforcing truss bar on said movable blade positioned to prevent distortion of said movable blade relative to said fixed blade.
Claim 5
Dependent Claim
44 words
The apparatus of claim 3 including clamp means to hold metal plate in position between said blades, said clamp means mounted for sliding movement on said frame and actuated by a pair of high leverage levers, said levers hydraulically actuated from said hydraulic means.
Claim 6
Dependent Claim
52 words
The apparatus of claim 4 in which said movable blade comprises a rectangular four edged blade carried at a slight angle in a slot in a blade carrier, said blade carrier being supported on rods connected to said first spring means and guided by adjustable guideways at its edges in said frame.
Claim 7
Dependent Claim
20 words
The apparatus of claim 5 including a roller bearing means between one edge of said blade carrier and its guideway.
Claim 8
Dependent Claim
25 words
The apparatus of claim 6 in which said ramp means comprises a pluRality of ramp shaped blocks on the top edge of said blade carrier.
Claim 9
Dependent Claim
68 words
The apparatus of claim 7 in which said roller assemblies each comprise an axle which supports a central roller shaped to ride on one of said ramp shaped blocks and a pair of slightly larger rollers on said axle on each side of the central roller shaped to ride along a first transverse member in said frame, said axle being carried at its end by said connector bars.
Claim 10
Dependent Claim
45 words
The apparatus of claim 8 in which said hydraulic means includes a pump driven main hydraulic cylinder connected to said connector bars and said levers are each actuated by a hydraulic cylinder adapted to be driven from the same pump as the main hydraulic cylinders.
Claim 11
Dependent Claim
41 words
The apparatus of claim 9 in which said first transverse member is welded at its ends to said frame and in which said fixed blade is mounted to a second transverse member which is welded at its ends into said frame.
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) | 1975-07-25 | 1976-01-24 | 1976-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-25 | 1980-01-24 | 1980-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-25 | 1984-01-24 | 1984-07-25 | $7700.00 | Window Closed / Lapsed |