US3858264A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Safety lock mechanism for a dockboard
Assignee: Kelly Co Inc
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Filing: 1973-11-30
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Granted: 1975-01-07
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Expires: 1993-11-30
Abstract
Abstract A safety lock mechanism for a dockboard to prevent lowering of the ramp and eliminating the possibility of gaining access to a building through the space between the lowered ramp and a closed overhead door. The dockboard includes a ramp hinged at its rear edge to the loading dock and a lip is hinged to the front edge of the ramp and is movable between a downwardly hanging, pendant position and an extended position. Cross traffic legs are pivoted to the under surface of the front edge of the ramp and engage fixed legs on the supporting structure of the dockboard to support the ramp in either a dock level position or in a series of below dock level positions. The cross traffic legs are coupled to the lip so that on movement of the lip from the pendant to the extended position, the cross traffic legs will be retracted. The safety lock mechanism includes a flange or stop which is pivotally connected to each fixed leg, and when the cross traffic leg is supported on the fixed leg the flange extends vertically to the rear of the cross traffic leg, to thereby prevent the cross traffic leg from being retracted when the ramp is at a dock level position. In the event that the ramp is just slightly above dock level when a truck pulls away from a dock, the lip will fall to its pendant position and the cross traffic legs will pivot forwardly into engagement with the stop, thereby pivoting the stop forwardly and enabling the cross traffic legs to engage the fixed legs.
Inventors
- 👤 Robert C Kuhns
- 👤 Robert D Metro
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 09:42
CPC Classifications
B; B65; B65G; B65G69/00; B65G69/28; B65G69/2805; B65G69/2811; B65G69/2835; B65G69/2841; B65G69/287; B65G69/2876; B65G69/2894
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
291 words
In a dockboard having a supporting structure and a ramp structure with the rear end of the ramp structure being hinged to the supporting structure, a lip hinged to the forward edge of the ramp structure and movable between a downwardly hanging pendant position and an outwardly extending position in which the lip forms an extension of the ramp structure, a movable leg mounted for movement on one of said structures between a supporting position and a non-supporting position, a fixed leg connected to the other of said structures and adapted to be engaged by said movable leg when the movable leg is in the supporting position to thereby support the ramp structure at a given inclination, the improvement comprising a safety stop member pivotally connected to the fixed leg and having an obstructing position wherein said stop member prevents movement of the movable leg to the nonsupporting position, pivotal means for mounting said stop member for forward pivotal movement from said obstructing position to a non-obstructing position where the stop member will not obstruct movement of said movable leg to the supporting position, and means to bias the stop member rearwardly to the obstructing position, said stop member when in the obstructing position preventing rearward movement of the movable leg to the nonsupporting position when the ramp structure is in a generally horizontal dock level position and thereby preventing lowering of the ramp structure, said stop member being disposed to be engaged by the movable leg as the movable leg moves from the nonsupporting position toward the supporting position with the ramp structure slightly above dock level, whereby said movable leg pivots the stop member to said non-obstructed position to enable the movable leg to move to the supporting position.
Claim 2
Dependent Claim
291 words
In a dockboard having a supporting structure and a ramp structure with the rear end of the ramp structure being hinged to the supporting structure, a lip hinged to the forward edge of the ramp structure and movable between a downwardly hanging pendant position and an outwardly extending position in which the lip forms an extension of the ramp structure, a movable leg mounted for movement on one of said structures between a supporting position and a non-supporting position, a fixed leg connected to the other of said structures and adapted to be engaged by said movable leg when the movable leg is in the supporting position to thereby support the ramp structure at a given inclination, the improvement comprising a safety stop member pivotally connected to the fixed leg and having an obstructing position wherein said stop member prevents movement of the movable leg to the nonsupporting position, pivotal means for mounting said stop member for forward pivotal movement from said obstructing position to a non-obstructing position where the stop member will not obstruct movement of said movable leg to the supporting position, and means to bias the stop member rearwardly to the obstructing position, said stop member when in the obstructing position preventing rearward movement of the movable leg to the nonsupporting position when the ramp structure is in a generally horizontal dock level position and thereby preventing lowering of the ramp structure, said stop member being disposed to be engaged by the movable leg as the movable leg moves from the nonsupporting position toward the supporting position with the ramp structure slightly above dock level, whereby said movable leg pivots the stop member to said non-obstructed position to enable the movable leg to move to the supporting position.
Claim 3
Dependent Claim
22 words
The dockboard of claim 1, and includIng stop means to prevent rearward pivotal movement of said stop member beyond said obstructing position.
Claim 4
Dependent Claim
23 words
The dockboard of claim 1, wherein the stop member when in the obstructing position is located to the rear of the movable leg.
Claim 5
Dependent Claim
26 words
The dockboard of claim 1, wherein the movable leg is pivotally connected to the ramp structure and the fixed leg is secured to the supporting structure.
Claim 6
Dependent Claim
20 words
The dockboard of claim 3, wherein said pivotal means is connected to the upper end portion of the fixed leg.
Claim 7
Dependent Claim
77 words
The dockboard of claim 2, wherein the stop member is generally L-shaped and includes a first flange and a second flange, said first flange being located to the rear of the movable leg when the stop member is in the obstructing position, said stop means comprising an abutment on said fixed leg and disposed to be engaged by said second flange to provide a stop and prevent rearward movement of the first flange beyond the obstructing position.
Claim 8
Dependent Claim
41 words
The dockboard of claim 1 and including means for coupling the movable leg to the lip whereby movement of the lip from the pendant to the extended position will move the movable leg from the supporting position to the non-supporting position.
Claim 9
Dependent Claim
333 words
In a dockboard having a supporting structure and a ramp with the rear end of the ramp being hinged to the supporting structure, a lip hinged to the forward edge of the ramp and movable between a downwardly hanging pendant position and an outwardly extending position in which the lip forms an extension of the ramp, a movable leg mounted for pivotal movement on the ramp between a supporting position and a retracted non-supporting position, a fixed leg connected to the supporting structure and adapted to be engaged by said movable leg when the movable leg is in the supporting position to thereby support the ramp at a given inclination, means for coupling the movable leg to the lip whereby movement of the lip from the pendant to the extended position will move the movable leg from the supporting position to the retracted non-supporting position, the improvement comprising a safety stop member pivotally connected to the fixed leg and having a generally vertical obstructing position wherein said stop member prevents pivotal movement of the movable leg to the non-supporting position, hinge means for mounting said stop member for forward pivotal movement from said obstructing position to a generally horizontal non-obstructing position where the stop member will not obstruct movement of said movable leg to the supporting position, and means to bias the stop member rearwardly to the obstructing position, said stop member when in the obstructing position being located to the rear of the movable leg and preventing rearward movement of the movable leg to the non-supporting position when the ramp is in a generally horizontal dock level position and thereby preventing lowering of the ramp, said stop member being disposed to be engaged by the movable leg as the movable leg pivots from the retracted non-supporting position toward the supporting position with the ramp slightly above dock level, whereby said movable leg will pivot the stop member to said non-obstructed position to enable the movable leg to move to the supporting position.
Claim 10
Dependent Claim
333 words
In a dockboard having a supporting structure and a ramp with the rear end of the ramp being hinged to the supporting structure, a lip hinged to the forward edge of the ramp and movable between a downwardly hanging pendant position and an outwardly extending position in which the lip forms an extension of the ramp, a movable leg mounted for pivotal movement on the ramp between a supporting position and a retracted non-supporting position, a fixed leg connected to the supporting structure and adapted to be engaged by said movable leg when the movable leg is in the supporting position to thereby support the ramp at a given inclination, means for coupling the movable leg to the lip whereby movement of the lip from the pendant to the extended position will move the movable leg from the supporting position to the retracted non-supporting position, the improvement comprising a safety stop member pivotally connected to the fixed leg and having a generally vertical obstructing position wherein said stop member prevents pivotal movement of the movable leg to the non-supporting position, hinge means for mounting said stop member for forward pivotal movement from said obstructing position to a generally horizontal non-obstructing position where the stop member will not obstruct movement of said movable leg to the supporting position, and means to bias the stop member rearwardly to the obstructing position, said stop member when in the obstructing position being located to the rear of the movable leg and preventing rearward movement of the movable leg to the non-supporting position when the ramp is in a generally horizontal dock level position and thereby preventing lowering of the ramp, said stop member being disposed to be engaged by the movable leg as the movable leg pivots from the retracted non-supporting position toward the supporting position with the ramp slightly above dock level, whereby said movable leg will pivot the stop member to said non-obstructed position to enable the movable leg to move to the supporting position.
References Cited (Backward Citations)
US3137017A
Cited
US3299456A
Cited
US3203002A
Cited
US3368229A
Cited
US3530488A
Cited
US3606627A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-06 | 1978-07-08 | 1979-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-06 | 1982-07-08 | 1983-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-06 | 1986-07-08 | 1987-01-07 | $7700.00 | Window Closed / Lapsed |