US4735003A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Protective toe cap for footwear
Assignee: BURKE INDUSTRIES (DELAWARE) Inc
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Filing: 1986-11-12
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Granted: 1988-04-05
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Expires: 2006-11-12
Abstract
Abstract A toe cap for internally reinforcing the toe of safety shoes, boots, and the like to protect the wearer against heavy compression or impact loads is made from a plastic material, and is designed with a flexible roof region in order to shift stresses generated by such loads to the lateral and forward wall regions which are more capable of supporting the loads and yield higher load-carrying capacities.
Inventors
- 👤 John L. Dykeman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:40
CPC Classifications
A; A43; A43B; A43B23/00; A43B23/08; A43B23/081; A43B23/086; A43B23/087; A43C; A43C13/00; A43C13/14
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
175 words
A non-metallic toe cap for installation in footwear to provide structural reinforcement of the toe area against compression and impact loading comprising: a shell body made from a plastic material and having the shape of a shoe toe with a rearward facing opening at the entrance of a toe pocket for insertion and withdrawal of the toes, the body including a roof region extending forwardly to a front wall region and laterally from a generally uppermost elevation at a central plane to opposite lateral wall regions, the lateral and front wall regions being joined with each other and with the roof region by smooth continuous curves conforming to a shoe toe to form the shell body, the wall regions also projecting upwardly away from a generally planar base shaped to conform to the front part of a shoe sole, and the roof region having means for shifting the fracture point of the plastic material under compression and impact loads outwardly from the central plane of the roof region toward locations in the lateral wall regions.
Claim 2
Dependent Claim
175 words
A non-metallic toe cap for installation in footwear to provide structural reinforcement of the toe area against compression and impact loading comprising: a shell body made from a plastic material and having the shape of a shoe toe with a rearward facing opening at the entrance of a toe pocket for insertion and withdrawal of the toes, the body including a roof region extending forwardly to a front wall region and laterally from a generally uppermost elevation at a central plane to opposite lateral wall regions, the lateral and front wall regions being joined with each other and with the roof region by smooth continuous curves conforming to a shoe toe to form the shell body, the wall regions also projecting upwardly away from a generally planar base shaped to conform to the front part of a shoe sole, and the roof region having means for shifting the fracture point of the plastic material under compression and impact loads outwardly from the central plane of the roof region toward locations in the lateral wall regions.
Claim 3
Dependent Claim
57 words
A non-metallic toe cap as defined in claim 1 wherein the means for shifting comprises means for providing the roof region with flexibility sufficient to deflect under compression and impact loads without fracture of the plastic material at the central plane and thereby shift load stresses outwardly from the plane toward locations in the lateral wall regions.
Claim 4
Dependent Claim
50 words
A non-metallic toe cap as defined in claim 2 wherein the means for shifting comprises means defining a series of grooves extending parallel to the central plane in the roof region of the body shell and partially penetrating into the plastic material to increase the flexibility of the roof region.
Claim 5
Dependent Claim
22 words
A non-metallic toe cap as defined in claim 3 wherein the grooves are located on the exterior surface of the roof region.
Claim 6
Dependent Claim
22 words
A non-metallic toe cap as defined in claim 3 wherein the grooves are located on the interior surface of the roof region.
Claim 7
Dependent Claim
24 words
A non-metallic toe cap as defined in claim 3 wherein the grooves are located on the interior and exterior surfaces of the roof region.
Claim 8
Dependent Claim
51 words
A non-metallic toe cap as defined in claim 2 wherein the means for shifting comprises a roof region having a reduced wall thickness adjacent the central plane to provide said flexibility in the roof region at a position remote from the lateral wall regions toward which the load stresses are shifted.
Claim 9
Dependent Claim
35 words
A non-metallic toe cap as defined in claim 2 wherein the means for shifting comprises a roof region composed of a plastic material different from the plastic material of the front and lateral wall regions.
Claim 10
Dependent Claim
19 words
A non-metallic toe cap as defined in claim 1 wherein the shell body is made from a thermoplastic material.
Claim 11
Dependent Claim
20 words
A non-metallic toe cap as defined in claim 1 wherein the shell body is made from a thermoset plastic material.
Claim 12
Dependent Claim
21 words
A non-metallic toe cap as defined in claim 1 wherein the shell body is made from a fiber reinforced plastic resin.
Claim 13
Dependent Claim
44 words
A non-metallic toe cap as defined in claim 1 wherein: the roof region is arcuately shaped in longitudinal and lateral planes, and the point on the exterior of the roof region most distant from the base plane is located in the central, longitudinal plane.
Claim 14
Dependent Claim
36 words
A non-metallic toe cap as defined in claim 12 wherein the point on the exterior of the roof region most distant from the base plane is located forward of the rear edge of the roof region.
Claim 15
Dependent Claim
138 words
In a reinforced safety shoe or the like, a non-metallic toe cap comprising a shell body formed from plastic in the shape of the shoe toe and fitting within the front portion of the shoe, the body having a roof region on the top, lateral wall regions disposed at opposite sides and joined with a front wall region and the roof region to form a generally smooth, continuous body with a generally planar base mating with the shoe sole, the roof region having an arcuate shape in a plane transverse to a central plane, the central plane extending fore and aft intermediate the lateral wall regions, the roof region including means for shifting fracture stresses in the plastic material of the roof region outwardly away from the central plane of the roof region toward the lateral wall regions.
Claim 16
Dependent Claim
138 words
In a reinforced safety shoe or the like, a non-metallic toe cap comprising a shell body formed from plastic in the shape of the shoe toe and fitting within the front portion of the shoe, the body having a roof region on the top, lateral wall regions disposed at opposite sides and joined with a front wall region and the roof region to form a generally smooth, continuous body with a generally planar base mating with the shoe sole, the roof region having an arcuate shape in a plane transverse to a central plane, the central plane extending fore and aft intermediate the lateral wall regions, the roof region including means for shifting fracture stresses in the plastic material of the roof region outwardly away from the central plane of the roof region toward the lateral wall regions.
Claim 17
Dependent Claim
42 words
A non-metallic toe cap as defined in claim 14 wherein the means for shifting the stresses comprises means rendering the roof region flexible relative to the wall regions under compression and impact loads applied near the central plane of the roof region.
Claim 18
Dependent Claim
46 words
A non-metallic toe cap as defined in claim 15 wherein the means for rendering comprises means defining a series of grooves extending parallel to the central plane in the roof region of the toe cap and penetrating into surface of the generally smooth, continuous shell body.
Claim 19
Dependent Claim
48 words
A non-metallic toe cap as defined in claim 16 wherein the series of grooves extends forwardly in the roof region from the rear edge of the toe cap to positions in the roof region intermediate the front of the cap and the rear edge of the roof region.
Claim 20
Dependent Claim
26 words
A non-metallic toe cap as defined in claim 15 wherein the means for rendering the roof region flexible comprises a roof region of reduced wall thickness.
Claim 21
Dependent Claim
35 words
A non-metallic toe cap as defined in claim 15 wherein the means rendering the roof region flexible comprises a roof region constructed of another plastic material more flexible than the material forming the wall region.
Claim 22
Dependent Claim
70 words
A non-metallic toe cap in a reinforced safety shoe as defined in claim 14 wherein: the roof region of the shell body also has an arcuate shape along the central plane between the rear edge of the roof region and the front wall region, and the maximum height of the roof region in the central plane above the base is located forward of the rear edge of the roof region.
Claim 23
Dependent Claim
23 words
A non-metallic toe cap as defined in claim 1 further including means positioned on the planar base for engaging an underlying shoe sole.
Claim 24
Dependent Claim
28 words
A non-metallic toe cap as defined in claim 20 wherein the means for engaging comprises a projection extending downwardly away from the planar base under the wall regions.
Claim 25
Dependent Claim
46 words
In a non-metallic reinforced safety shoe or the like having a sole, a toe cap according to claim 14 further including means for engaging the lower wall regions of the toe cap with the shoe sole to prevent the wall regions from spreading outwardly under load.
References Cited (Backward Citations)
US1859452A
Cited
US2091223A
Cited
US2079237A
Cited
GB487761A
Cited
US2392867A
Cited
GB678031A
Cited
US2795868A
Cited
US3407518A
Cited
GB1284736A
Cited
US3593438A
Cited
US3950865A
Cited
EP0021612A1
Cited
FR2525443A1
Cited
EP0095061A1
Cited
US4575953A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-04-05 | 1991-10-05 | 1992-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-05 | 1995-10-05 | 1996-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-05 | 1999-10-05 | 2000-04-05 | $7700.00 | Window Closed / Lapsed |