US5214818A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dock leveler operating apparatus
Assignee: GLOBAL TECHNOLOGIES Inc (GTI)
•
Filing: 1992-07-16
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Granted: 1993-06-01
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Expires: 2012-07-16
Abstract
Abstract An apparatus for operating a dock leveler including a linkage pivotally connected at a first end to the base plate. The second end of the linkage is adapted to selectively engage the center plate at times when the center plate is pivoted from its forward position toward its rearward position. Preferably, a roller is provided on the second end of the linkage and a cam member is mounted on the underside of the center plate in alignment with the path of the roller, such that the roller travels along the cam member to reduce the force required to operate the center plate pivoting means. A lever tube is rigidly connected to the second end of the linkage and is adapted to hold an operating lever. The operating lever is in a substantially vertical orientation at times when the center plate is in the stored and bridging positions. When the center plate is in the retracted position, the operating lever is adapted to be in a position that is easily reachable by the operator with only a minimal degree of bending required.
Inventors
- 👤 Bobby A. Cook
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:22
CPC Classifications
B; B65; B65G; B65G69/00; B65G69/28; B65G69/2805; B65G69/2811; B65G69/2835; B65G69/2841
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
236 words
A dock leveler for bridging a gap between a loading dock and a carrier bed, comprising: a base plate to be attached to the loading dock; a center plate having first and second opposite edges, said first edge pivotally connected to the base plate for pivotal movement in rearward and forward directions between a rearward position and a forward position; a lip plate having first and second opposite edges, the first edge of the lip plate pivotally connected to the second edge of the center plate for pivotal movement between a retracted position, a stored position, and a bridging position in which the lip plate is substantially coplanar with and forms an extension of the center plate; and center plate pivoting means for pivoting the center plate from the forward position to the rearward position, the center plate pivoting means including a cam member mounted on the center plate and a linkage pivotally connected to the base plate, said cam member having a ramp-like surface for reducing the effort required for operation of the center plate pivoting means, the linkage having a first end pivotally connected to the base plate and a second end adapted to selectively engage said ramp-like surface of the cam member and move along said ramp-like surface between the first and second opposite edges of the center plate as the center plate is pivoted from the forward position to the rearward position.
Claim 2
Dependent Claim
236 words
A dock leveler for bridging a gap between a loading dock and a carrier bed, comprising: a base plate to be attached to the loading dock; a center plate having first and second opposite edges, said first edge pivotally connected to the base plate for pivotal movement in rearward and forward directions between a rearward position and a forward position; a lip plate having first and second opposite edges, the first edge of the lip plate pivotally connected to the second edge of the center plate for pivotal movement between a retracted position, a stored position, and a bridging position in which the lip plate is substantially coplanar with and forms an extension of the center plate; and center plate pivoting means for pivoting the center plate from the forward position to the rearward position, the center plate pivoting means including a cam member mounted on the center plate and a linkage pivotally connected to the base plate, said cam member having a ramp-like surface for reducing the effort required for operation of the center plate pivoting means, the linkage having a first end pivotally connected to the base plate and a second end adapted to selectively engage said ramp-like surface of the cam member and move along said ramp-like surface between the first and second opposite edges of the center plate as the center plate is pivoted from the forward position to the rearward position.
Claim 3
Dependent Claim
31 words
The dock leveler of claim 1, wherein the second end of the linkage is adapted to disengage from the ramp-like surface as the center plate is pivoted to the forward position.
Claim 4
Dependent Claim
22 words
The dock leveler of claim 2, wherein the first end of the linkage includes means for limiting pivotal movement of the linkage.
Claim 5
Dependent Claim
32 words
The dock leveler of claim 3, wherein the limiting means includes a protrusion at the first end of the linkage for engaging the loading dock to limit pivotal movement of the linkage.
Claim 6
Dependent Claim
41 words
The dock leveler of claim 1, wherein the center plate pivoting means includes manually actuatable means, said manually actuatable means comprising a lever tube connected adjacent the second end of the linkage and an operating lever disposed in said lever tube.
Claim 7
Dependent Claim
26 words
The dock leveler of claim 5, wherein the lever is in a substantially vertical orientation at times when the center plate is in the forward position.
Claim 8
Dependent Claim
48 words
The dock leveler of claim 1, wherein the second end of the linkage includes a roller adapted to roll along said ramp-like surface between the first and second opposite edges of the center plate as the center plate is pivoted in the rearward direction from the forward position.
Claim 9
Dependent Claim
42 words
The dock leveler of claim 1, wherein the second end of the linkage includes means for sliding between the first and second opposite edges of the center plate as the center plate is pivoted in the rearward direction from the forward position.
Claim 10
Dependent Claim
15 words
The dock leveler of claim 1, wherein the linkage is unitary and is substantially L-shaped.
Claim 11
Dependent Claim
31 words
The dock leveler of claim 1, further comprising a lip extension means for pivoting the lip plate toward the bridging position as the center plate pivots forward from the rearward position.
Claim 12
Dependent Claim
88 words
The dock leveler of claim 10, further comprising support gusset connected to the base plate; and further wherein the lip extension means includes an extension bar having a first end pivotally connected to the lip plate and a stop member attached to the support gusset, said extension bar includes a free second end adapted to engage the stop member when the center plate is in the rearward position to pivot the lip plate toward the bridging position as the center plate is pivoted forward from the rearward position.
Claim 13
Dependent Claim
36 words
The dock leveler of claim 11, wherein the second end of the extension bar is adapted to disengage from the stop member after the center plate is pivoted forward a predetermined distance from the rearward position.
Claim 14
Dependent Claim
30 words
The dock leveler of claim 12, wherein the stop member includes an angled portion and the extension bar is adapted to disengage from said angled portion in a sear-type action.
Claim 15
Dependent Claim
49 words
The dock leveler of claim 1, further comprising a stop bar connected to the lip plate, said stop bar adapted to engage the center plate at times when the center plate is in the rearward position to maintain a predetermined angle between the center plate and the lip plate
Claim 16
Dependent Claim
13 words
The dock leveler of claim 14, wherein the predetermined angle is approximately 60°.
Claim 17
Dependent Claim
19 words
The dock leveler of claim 1, further comprising a biasing means for urging the linkage in a forward direction.
Claim 18
Dependent Claim
174 words
A center plate pivoting apparatus for operating a dock leveler having a base plate to be attached to a loading dock, a center plate pivotally connected to the base plate for pivotal movement in rearward and forward directions between a full rearward position and a forward position, and a lip plate pivotally connected to the center plate for pivotal movement between a retracted position, a stored position, and a bridging position in which the lip plate is substantially coplanar with and forms an extension of the center plate, the apparatus comprising: a cam member mounted on the center plate for reducing the effort required for operation of the apparatus, the cam member having a ramp-like surface; and a linkage having a first end pivotally connected to the base plate and a second end adapted to selectively engage said ramp-like surface of the cam member move along said ramp-like surface between the first and second opposite edges of the center plate as the center plate is pivoted from the forward position to the rearward position.
Claim 19
Dependent Claim
174 words
A center plate pivoting apparatus for operating a dock leveler having a base plate to be attached to a loading dock, a center plate pivotally connected to the base plate for pivotal movement in rearward and forward directions between a full rearward position and a forward position, and a lip plate pivotally connected to the center plate for pivotal movement between a retracted position, a stored position, and a bridging position in which the lip plate is substantially coplanar with and forms an extension of the center plate, the apparatus comprising: a cam member mounted on the center plate for reducing the effort required for operation of the apparatus, the cam member having a ramp-like surface; and a linkage having a first end pivotally connected to the base plate and a second end adapted to selectively engage said ramp-like surface of the cam member move along said ramp-like surface between the first and second opposite edges of the center plate as the center plate is pivoted from the forward position to the rearward position.
Claim 20
Dependent Claim
30 words
The apparatus of claim 17, wherein the second end of the linkage is adapted to disengage from said ramp-like surface as the center plate is pivoted to the forward position.
Claim 21
Dependent Claim
21 words
The apparatus of claim 17, wherein the first end of the linkage includes means for limiting pivotal movement of the linkage.
Claim 22
Dependent Claim
50 words
The apparatus of claim 17, further comprising manually actuatable means which includes a lever tube connected adjacent the second end of the linkage and an operating lever disposed in said lever tube, said operating lever being in a substantially vertical orientation when the center plate is in the forward position.
Claim 23
Dependent Claim
51 words
The apparatus of claim 17, wherein the second end of the linkage includes a roller adapted to roll along the ramp-like surface of the cam member between the first and second opposite edges of the center plate as the center plate is pivoted in the rearward direction from the forward position.
Claim 24
Dependent Claim
17 words
The apparatus of claim 17, further comprising biasing means for urging the linkage in the forward direction.
Claim 25
Dependent Claim
29 words
The apparatus of claim 17, further comprising lip extension means for pivoting the lip plate toward the bridging position as the center plate pivots forward from the rearward position.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-05-31 | 1996-11-30 | 1997-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-05-31 | 2000-11-30 | 2001-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-05-31 | 2004-11-30 | 2005-06-01 | $7700.00 | Window Closed / Lapsed |