US3808682A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pneumatically driven shear
Assignee: Individual
•
Filing: 1972-01-10
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Granted: 1974-05-07
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Expires: 1992-01-10
Abstract
Abstract A three-bladed pneumatically driven shear in which the central, moving blade is provided with a transverse and longitudinal curved surface on its lower edge to reduce frictional contact between the blade and the material to be severed and to allow the cutter to make relatively small radius cuts in the material being severed. The transverse curvature on the bottom of the blade prevents it from biting into the material and inhibiting the turning of the cutter along a radius on the material being severed. The side, fixed blades are beveled on the lower surfaces in order to allow the operator to rotate the cutter about a vertical axis passing through the point of sharing without damaging the workpiece or the cutters while shearing along a curve. One of the side blades is positioned on the cutter so as to extend slightly below the bottom of the other side blade, thereby causing the center blade to commence cutting at one side of the cutter before the other. This facilitates the removal of the chip formed by the severed material by forcing it to curl off to one side away from the cutter. The central blade is formed so as to extend beyond the ends of the side blades in order to facilitate initial engagement with the material to be severed.
Inventors
- 👤 K Sumida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 08:43
CPC Classifications
B; B23; B23D; B23D29/00; B23D29/005
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
184 words
A shear comprising a housing, at least one blade fixed to said housing so as to extend therefrom and having a cutting edge thereon located in a workpiece-contacting plane such that said housing is positioned at an acute angle relative to, and removed from any contact with, a workpiece against which said cutting edge is positioned, a movable blade pivotally mounted on said at least one fixed blade and having a cutting edge thereon, means pivotally mounting said movable blade on said at least one fixed blade, means for driving said movable blade in only one direction about said pivotal mounting means for cooperation of said fixed blade cutting edge and said movable blade cutting edge to sever a workpiece comprising motor means in said housing, cam means in said housing and operatively connected to said motor means to be driven thereby, and cam follower means operatively connected to said movable blade and actuated by said cam means to drive said movable blade about said pivotal mounting means only in a direction in which said cutting edges of said blades close in scissors-like fashion.
Claim 2
Dependent Claim
184 words
A shear comprising a housing, at least one blade fixed to said housing so as to extend therefrom and having a cutting edge thereon located in a workpiece-contacting plane such that said housing is positioned at an acute angle relative to, and removed from any contact with, a workpiece against which said cutting edge is positioned, a movable blade pivotally mounted on said at least one fixed blade and having a cutting edge thereon, means pivotally mounting said movable blade on said at least one fixed blade, means for driving said movable blade in only one direction about said pivotal mounting means for cooperation of said fixed blade cutting edge and said movable blade cutting edge to sever a workpiece comprising motor means in said housing, cam means in said housing and operatively connected to said motor means to be driven thereby, and cam follower means operatively connected to said movable blade and actuated by said cam means to drive said movable blade about said pivotal mounting means only in a direction in which said cutting edges of said blades close in scissors-like fashion.
Claim 3
Dependent Claim
46 words
The shear of claim 1 including means on the end of said movable blade distal from said cam follower means for forcing said cam follower means into contact with said cam means as said housing is pushed across a workpiece to be severed by an operator.
Claim 4
Dependent Claim
105 words
A shear comprising a housing, a pair of blades fixed to said housing, a movable blade intermediate said fixed blades and cooperable therewith to sever a workpiece therebetween, motor means mounted in said housing and having cam means operably driven thereby, cam follower means mounted on said movable blade for cooperation with said cam means to drive said movable blade only into a closed position relative to said fixed blades, and means on the leading end of said movable blade for forcing said movable blade into an open position relative to said fixed blades as an operator pushes said housing across a workpiece being severed.
Claim 5
Dependent Claim
105 words
A shear comprising a housing, a pair of blades fixed to said housing, a movable blade intermediate said fixed blades and cooperable therewith to sever a workpiece therebetween, motor means mounted in said housing and having cam means operably driven thereby, cam follower means mounted on said movable blade for cooperation with said cam means to drive said movable blade only into a closed position relative to said fixed blades, and means on the leading end of said movable blade for forcing said movable blade into an open position relative to said fixed blades as an operator pushes said housing across a workpiece being severed.
Claim 6
Dependent Claim
44 words
The shear of claim 3 wherein said motor means comprises an air driven motor having exhaust means situated within said housing so as to direct air being exhausted from said motor over and past said fixed and movable blades to cool and lubricate them.
Claim 7
Dependent Claim
43 words
The shear of claim 3 whrein said pair of fixed blades include beveled surfaces extending away from the said cutting edges thereon so that the cutter may be rotated about the axis of said housing in order to cut along a curved path.
Claim 8
Dependent Claim
78 words
The shear of claim 3 wherein said pair of fixed blades include elongated cutting edges in parallel relation-ship to one another and separated in a horizontal plane by a distance which is substantially equal to the width of said movable blade plus a relatively small clearance and separated in a vertical plane by a distance which is sufficient to prevent simultaneous cutting by movement of said movable blade thereagainst at the same longitudinal location along both cutting edges.
Claim 9
Dependent Claim
39 words
The shear of claim 3 wherein said movable cutting blade is provided with a lower surface having a longitudinal arcuate configuration and a transverse arcuate configuration throughout that portion of the length thereof which extends below said fixed blades.
Claim 10
Dependent Claim
52 words
The shear of claim 3 wherein said motor means comprises a pneumatic motor and includes means for directing the air being exhausted from said pneumatic motor over and past said fixed and movable blades to cool said blades and to lubricate them when oil is injected into the air driving said motor.
Claim 11
Dependent Claim
98 words
The shear of claim 8 wherein said movable blade comprises a pair of cutting edges extending along the upper surface thereof and so located thereon as to cooperate with cutting edges on said fixed blades in a progressive shearing relationship when said movable blade is driven by said cam means, said fixed blades each include a cutting edge operatively associated with a cutting edge on said movable blade and means for forcing the chip generated by the progressive shearing action to be curled away to one side of the shear as the shear is moved across a workpiece.
Claim 12
Dependent Claim
57 words
The shear of claim 9 wherein said chip forcing means comprises means for locating the cutting edges of said fixed blades in such a relationship that the progressive shearing along one such cutting edge occurs prior to the progressive shearing along the other such cutting edge at any given position along the length of said movable blade.
Claim 13
Dependent Claim
119 words
A shear comprising a housing including drive means therein comprising a pneumatic motor, a pair of fixed blades mounted adjacent one end of said housing, a movable blade pivotally mounted between said pair of fixed blades and including means operatively associated with said drive means for oscillatably moving said movable blade relative to said pair of fixed blades and a lower arcuate surface formed on said movable blade to prevent the lower surface thereof rom acting as a secondary cutting edge, and means for directing the air being exhausted from said pneumatic motor over and past said fixed and movable blades to cool said blades and to lubricate them when oil is injected into the air driving said motor.
Claim 14
Dependent Claim
119 words
A shear comprising a housing including drive means therein comprising a pneumatic motor, a pair of fixed blades mounted adjacent one end of said housing, a movable blade pivotally mounted between said pair of fixed blades and including means operatively associated with said drive means for oscillatably moving said movable blade relative to said pair of fixed blades and a lower arcuate surface formed on said movable blade to prevent the lower surface thereof rom acting as a secondary cutting edge, and means for directing the air being exhausted from said pneumatic motor over and past said fixed and movable blades to cool said blades and to lubricate them when oil is injected into the air driving said motor.
Claim 15
Dependent Claim
49 words
The shear of claim 11 wherein each of said fixed blades includes means for providing a clearance between the lower surface of each blade and a workpiece being sheared sufficient to allow movement of the shear about the longitudinal axis thereof while shearing the workpiece along a curved path.
Claim 16
Dependent Claim
77 words
The shear of claim 11 wherein said drive means further includes means driven by said pneumatic motor and opera-tively associated with said movable blade for driving said movable blade only in a direction to effect a closed relationship with said fixed blades and said movable blade includes means on the leading end thereof for forcing said movable blade into an open relationship with said fixed blades as an operator pushes said housing across a workpiece being severed.
Claim 17
Dependent Claim
43 words
The shear of claim 11 wherein said pair of fixed blades include beveled surfaces extending away from the said cutting edges thereon so that the cutter may be rotated about an axis of said housing in order to cut along a curved path.
Claim 18
Dependent Claim
78 words
The shear of claim 11 wherein said pair of fixed blades include elongated cutting edges in parallel relationship to one another and separated in a horizontal plane by a distance which is substantially equal to the width of said movable blade plus a relatively small clearance and separated in a vertical plane by a distance which is sufficient to prevent simultaneous cutting by movament of said movable blade thereagainst at the same longitudinal location along both cutting edges.
Claim 19
Dependent Claim
98 words
The shear of claim 11 wherein said movable blade comprises a pair of cutting edges extending along the upper surface thereof and so located thereon as to cooperate with cutting edges on said fixed blades in a progressive shearing relationship when said movable blade is driven by said cam means, said fixed blades each include a cutting edge operatively associated with a cutting edge on said movable blade and means for forcing the chip generated by the progressive shearing action to be curled away to one side of the shear as the shear is moved across a workpiece.
Claim 20
Dependent Claim
57 words
The shear of claim 16 wherein said chip forcing means comprises means for locating the cutting edges of said fixed blades in such a relationship thaT the progressive shearing along one such cutting edge occurs prior to the progressive shearing along the other such cutting edge at any given position along the length of said movable blade.
Claim 21
Dependent Claim
95 words
A shear comprising a housing including drive means therein comprising a pneumatic motor, a pair of fixed blades mounted adjacent one end of said housing, a movable blade pivotally mounted between said pair of fixed blades and including means operatively associated with said drive means for oscillatably moving said movable blade relative to said pair of fixed blades, and means for directing the air being exhausted from said pneumatic motor over and past said fixed and movable blades to cool said blades and lubricate them when oil is injected into the air driving said motor.
Claim 22
Dependent Claim
95 words
A shear comprising a housing including drive means therein comprising a pneumatic motor, a pair of fixed blades mounted adjacent one end of said housing, a movable blade pivotally mounted between said pair of fixed blades and including means operatively associated with said drive means for oscillatably moving said movable blade relative to said pair of fixed blades, and means for directing the air being exhausted from said pneumatic motor over and past said fixed and movable blades to cool said blades and lubricate them when oil is injected into the air driving said motor.
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) | 1977-05-06 | 1977-11-05 | 1978-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-06 | 1981-11-05 | 1982-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-06 | 1985-11-05 | 1986-05-07 | $7700.00 | Window Closed / Lapsed |