US4428595A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fifth wheel hitch
Assignee: SW PELHAM FUND II LP
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Filing: 1982-03-01
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Granted: 1984-01-31
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Expires: 2002-03-01
Abstract
Abstract A fifth wheel hitch includes a kingpin locking mechanism having a pair of pivoting locking jaws which form a socket in which the kingpin is retained. An adjustment device varies the angular position of the closed jaws to vary the side-to-side dimension of the socket, and thereby compensate for side wear in the hitch. A stationary, semicircular bearing is fixedly mounted in the hitch to form a portion of the forward half of the socket, such that pivotal adjustment of the closed jaws also varies the fore-to-aft dimension of the socket, and thereby compensate for end wear in the hitch.
Inventors
- 👤 Samuel A. Martin
- 👤 Fredrick J. Bakker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:38
CPC Classifications
B; B62; B62D; B62D53/00; B62D53/04; B62D53/08; B62D53/0885
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
204 words
In a fifth wheel hitch having a support plate with an upper bearing surface and kingpin slot therethrough, and a pair of pivotally mounted jaws which are closed to define a socket in which a kingpin is retained in a locked position, and are opened to release said kingpin in an unlocked position; said socket having a generally vertically oriented central axis, and forward and rearward halves which define therebetween a fore-to-aft dimension and a side-to-side dimension; means for adjusting the angular position of said jaws in the closed, locked position for varying the side-to-side dimension of said socket to compensate for side wear in said hitch, the improvement comprising: a stationary bearing connected with said hitch, and having an arcuate plan shape which mates with said kingpin and forms at least a portion of the forward half of said socket; said bearing being fixed during hitch loading with respect to the central axis of said socket, whereby pivotal adjustment of said jaws varies the fore-to-aft dimension of said socket to compensate for end wear in said hitch; said stationary bearing extending upwardly through said kingpin slot to an elevation slightly below the upper bearing surface of said support plate for improved wear resistance.
Claim 2
Dependent Claim
204 words
In a fifth wheel hitch having a support plate with an upper bearing surface and kingpin slot therethrough, and a pair of pivotally mounted jaws which are closed to define a socket in which a kingpin is retained in a locked position, and are opened to release said kingpin in an unlocked position; said socket having a generally vertically oriented central axis, and forward and rearward halves which define therebetween a fore-to-aft dimension and a side-to-side dimension; means for adjusting the angular position of said jaws in the closed, locked position for varying the side-to-side dimension of said socket to compensate for side wear in said hitch, the improvement comprising: a stationary bearing connected with said hitch, and having an arcuate plan shape which mates with said kingpin and forms at least a portion of the forward half of said socket; said bearing being fixed during hitch loading with respect to the central axis of said socket, whereby pivotal adjustment of said jaws varies the fore-to-aft dimension of said socket to compensate for end wear in said hitch; said stationary bearing extending upwardly through said kingpin slot to an elevation slightly below the upper bearing surface of said support plate for improved wear resistance.
Claim 3
Dependent Claim
16 words
A trailer hitch as set forth in claim 1, wherein: said bearing shape is substantially semicircular.
Claim 4
Dependent Claim
21 words
A trailer hitch as set forth in claim 2, wherein: said bearing extends continuously about the forward half of said socket.
Claim 5
Dependent Claim
17 words
A trailer hitch as set forth in claim 3, wherein: said bearing is positioned above said jaws.
Claim 6
Dependent Claim
32 words
A trailer hitch as set forth in claim 4, wherein: said jaws are pivotally mounted on a pair of laterally spaced apart pins; and said bearing is fixedly mounted on said pins.
Claim 7
Dependent Claim
34 words
A trailer hitch as set forth in claim 5, wherein: said bearing comprises a flat plate having a semicircular opening through a rearward edge thereof, with a split sleeve upstanding from said flat plate.
Claim 8
Dependent Claim
17 words
A trailer hitch as set forth in claim 6, wherein: said split sleeve has wedge-shaped end edges.
Claim 9
Dependent Claim
21 words
A trailer hitch as set forth in claim 1, wherein: said bearing extends continuously about the forward half of said socket.
Claim 10
Dependent Claim
17 words
A trailer hitch as set forth in claim 1, wherein: said bearing is positioned above said jaws.
Claim 11
Dependent Claim
32 words
A trailer hitch as set forth in claim 1, wherein: said jaws are pivotally mounted on a pair of laterally spaced apart pins; and said bearing is fixedly mounted on said pins.
Claim 12
Dependent Claim
34 words
A trailer hitch as set forth in claim 1, wherein: said bearing comprises a flat plate having a semicircular opening through a rearward edge thereof, with a split sleeve upstanding from said flat plate.
Claim 13
Dependent Claim
17 words
A trailer hitch as set forth in claim 11, wherein: said split sleeve has wedge-shaped end edges.
Claim 14
Dependent Claim
206 words
In a fifth wheel hitch having a pair of jaws pivotally mounted on a pair of laterally spaced apart pins; said jaws being shaped such that when closed they define a socket therebetween in which a kingpin is retained in a locked position, and when opened they release said kingpin into an unlocked position; said socket having a generally vertically oriented central axis, and forward and rearward halves which define therebetween a fore-to-aft dimension and a side-to-side dimension; means for adjusting the angular position of said jaws in the closed, locked position for varying the side-to-side dimension of said socket to compensate for side wear in said hitch, the improvement comprising: a stationary bearing connected with said hitch, and having an arcuate plan shape which mates with said kingpin and forms at least a portion of the forward half of said socket; said bearing being fixed during hitch loading with respect to the central axis of said socket, whereby pivotal adjustment of said jaws varies the fore-to-aft dimension of said socket to compensate for end wear in said hitch; said bearing having a pair of laterally spaced apart apertures through which said jaw mounting pins are closely received to fixedly mount said bearing in said hitch.
Claim 15
Dependent Claim
206 words
In a fifth wheel hitch having a pair of jaws pivotally mounted on a pair of laterally spaced apart pins; said jaws being shaped such that when closed they define a socket therebetween in which a kingpin is retained in a locked position, and when opened they release said kingpin into an unlocked position; said socket having a generally vertically oriented central axis, and forward and rearward halves which define therebetween a fore-to-aft dimension and a side-to-side dimension; means for adjusting the angular position of said jaws in the closed, locked position for varying the side-to-side dimension of said socket to compensate for side wear in said hitch, the improvement comprising: a stationary bearing connected with said hitch, and having an arcuate plan shape which mates with said kingpin and forms at least a portion of the forward half of said socket; said bearing being fixed during hitch loading with respect to the central axis of said socket, whereby pivotal adjustment of said jaws varies the fore-to-aft dimension of said socket to compensate for end wear in said hitch; said bearing having a pair of laterally spaced apart apertures through which said jaw mounting pins are closely received to fixedly mount said bearing in said hitch.
Claim 16
Dependent Claim
51 words
A trailer hitch as set forth in claim 13, wherein: said hitch includes a fifth wheel support plate having a kingpin slot therethrough and an upper bearing surface; and said stationary bearing extends upwardly through said kingpin slot to an elevation slightly below said upper bearing surface for improved wear resistance.
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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) | 1987-01-30 | 1987-08-01 | 1988-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-30 | 1991-08-01 | 1992-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-30 | 1995-08-01 | 1996-01-31 | $7700.00 | Window Closed / Lapsed |