US3921765A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic brake slack adjuster
Assignee: Midland Brake Inc
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Filing: 1974-02-19
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Granted: 1975-11-25
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Expires: 1994-02-19
Abstract
Abstract An automatic brake slack adjuster is provided which includes a first drive unit; a second drive unit; an intermediate shaft unit positioned therebetween, and a body member defining cavities to receive the drive units and intermediate shaft unit. The second drive unit further includes a drive shaft having a worm rotatably mounted thereon. A first clutch means operable in a first rotational direction is positioned between the worm and the drive shaft and a second clutch means operable in a second opposite rotational direction is positioned between the gear and the body member.
Inventors
- 👤 Jr Kenneth D Swander
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:44
CPC Classifications
F; F16; F16D; F16D65/00; F16D65/38; F16D65/40; F16D65/52; F16D65/60
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
349 words
In a slack adjusting mechanism for vehicle brakes, an actuating arm assemblage comprising a body portion and an elongate actuating arm integral with the body portion, a first bore in the body portion, an internally splined first worm gear rotatably mounted in said bore and adapted to receive therethrougH a brake-actuating cam shaft, the actuating arm being adapted for connection with means for rocking the housing in application and release of the brake and the associated brake-actuating cam shaft, a second bore in the body portion extending at right angles to the turning axis of the worm gear and opening at one end thereof into the first bore, a connecting shaft rotatably mounted in the second bore and carrying a first worm thereon having driving connection through the first named opening with said first worm gear, a third bore in the body portion extending acrosss the other end of the second bore and opening thereinto, a second gear mounted on the connecting shaft with the threads thereof extending into the second named opening, a drive shaft rotatably mounted in the third bore carrying a second worm thereon having driving connection with the second gear through the second mentioned opening, a first clutch means communicating between said drive shaft and said second worm, said first clutch means operable on rotation of said shaft in a first direction to couple the second worm and drive shaft together for rotation one with the other, and on rotation of the shaft in the opposite direction to free the second worm and drive shaft for rotation of the latter without the former, and a second clutch means communcating between said second worm and body portion, said second clutch means operable on rotation of said drive shaft in said first direction to free the second worm and body portion from one another to permit rotation of the drive shaft and second worm together, and on rotation of the drive shaft in the opposite direction to couple the second worm and body portion together whereby to prevent rotation of the second worm with the drive shaft.
Claim 2
Dependent Claim
349 words
In a slack adjusting mechanism for vehicle brakes, an actuating arm assemblage comprising a body portion and an elongate actuating arm integral with the body portion, a first bore in the body portion, an internally splined first worm gear rotatably mounted in said bore and adapted to receive therethrougH a brake-actuating cam shaft, the actuating arm being adapted for connection with means for rocking the housing in application and release of the brake and the associated brake-actuating cam shaft, a second bore in the body portion extending at right angles to the turning axis of the worm gear and opening at one end thereof into the first bore, a connecting shaft rotatably mounted in the second bore and carrying a first worm thereon having driving connection through the first named opening with said first worm gear, a third bore in the body portion extending acrosss the other end of the second bore and opening thereinto, a second gear mounted on the connecting shaft with the threads thereof extending into the second named opening, a drive shaft rotatably mounted in the third bore carrying a second worm thereon having driving connection with the second gear through the second mentioned opening, a first clutch means communicating between said drive shaft and said second worm, said first clutch means operable on rotation of said shaft in a first direction to couple the second worm and drive shaft together for rotation one with the other, and on rotation of the shaft in the opposite direction to free the second worm and drive shaft for rotation of the latter without the former, and a second clutch means communcating between said second worm and body portion, said second clutch means operable on rotation of said drive shaft in said first direction to free the second worm and body portion from one another to permit rotation of the drive shaft and second worm together, and on rotation of the drive shaft in the opposite direction to couple the second worm and body portion together whereby to prevent rotation of the second worm with the drive shaft.
Claim 3
Dependent Claim
51 words
A slack adjusting mechanism as in claim 1 including manual adjustment means for disengagement of the second gear with the second worm and rotation of the connecting shaft, whereby to rotate the first worm gear and adjust the brake, said manual adjustment means accessible from the exterior of the body portion.
Claim 4
Dependent Claim
56 words
A mechanism as in claim 2 wherein the manual adjustment means includes: the second gear slidably mounted on said connecting shaft, removable retaining means normally holding the second gear in engagement with the second worm, and engaging means on said connecting shaft outboard of the second gear for engagement and manual rotation of said connecting shaft.
Claim 5
Dependent Claim
36 words
A slack adjusting mechanism as in claim 2 wherein said first clutch means includes a predetermined dwell therein, whereby rotation of said drive shaft in said first rotational direction does not initially engage said first clutch.
Claim 6
Dependent Claim
22 words
A slack adjusting mechanism as in claim 1 wherein said second bore is positioned above each of said first and third bores.
Claim 7
Dependent Claim
76 words
A slack adjuster mechanism as in claim 1 wherein the means for rocking the housing in application and release of the brake comprises a brake actuating rod pivotally connected to the elongate actuating arm, and a link rod connecting the brake actuating rod with the drive shaft through a crank arm for two-way rotation of the drive shaft on application and release of the brake, the link rod having a resilient portion intermediate the ends thereof.
Claim 8
Dependent Claim
38 words
A slack adjusting mechanism as in claim 1 wherein the first and second clutch means comprise oppositely wound helical springs encircling the drive shaft, same received at the inward ends thereof in opposed recesses in the second worm.
Claim 9
Dependent Claim
61 words
A slack adjusting mechanism as in claim 7 wherein the outboard end of one of said helical springs is received in a central inboard recess of a bearing keyed to the drive shaft and the outboard end of the other helical spring is received in a central inboard recess of a stationary bearing member fixed with respect to said body portion.
Claim 10
Dependent Claim
236 words
An automatic brake adjuster adapted to be interposed between a brake operating shaft and a brake actuaTing rod, said brake adjuster comprising: a first movement reducing drive unit connected to said brake operating shaft; a second movement reducing drive unit including a drive shaft coupled to a link connected to said brake actuating rod; a connecting shaft interposed between said first and second drive units and having drive linkages therewith, whereby rotation of the drive shaft in at least one direction will rotate the brake operating shaft; a body member defining cavities to receive said first and second drive units, said connecting shaft, said drive linkages and said brake operating shaft; said body member having an integral lever arm connected to said brake actuating rod at a point different from the connection of the latter with said link, whereby oscillation of said brake operating rod and arcuate movement of said adjuster causes said brake operating shaft to advance in small increments; a pair of clutches interposed in the drive between said link and said brake operating shaft; said clutches movable between an engaged position for one clutch and a disengaged position for the other clutch which permit movement of the link and drive shaft coupled therewith independently of said brake operating shaft, and opposite positions for said clutches, which opposite positions cause advance of the brake operating shaft upon movement of the link and drive shaft.
Claim 11
Dependent Claim
236 words
An automatic brake adjuster adapted to be interposed between a brake operating shaft and a brake actuaTing rod, said brake adjuster comprising: a first movement reducing drive unit connected to said brake operating shaft; a second movement reducing drive unit including a drive shaft coupled to a link connected to said brake actuating rod; a connecting shaft interposed between said first and second drive units and having drive linkages therewith, whereby rotation of the drive shaft in at least one direction will rotate the brake operating shaft; a body member defining cavities to receive said first and second drive units, said connecting shaft, said drive linkages and said brake operating shaft; said body member having an integral lever arm connected to said brake actuating rod at a point different from the connection of the latter with said link, whereby oscillation of said brake operating rod and arcuate movement of said adjuster causes said brake operating shaft to advance in small increments; a pair of clutches interposed in the drive between said link and said brake operating shaft; said clutches movable between an engaged position for one clutch and a disengaged position for the other clutch which permit movement of the link and drive shaft coupled therewith independently of said brake operating shaft, and opposite positions for said clutches, which opposite positions cause advance of the brake operating shaft upon movement of the link and drive shaft.
Claim 12
Dependent Claim
326 words
In an automatic brake adjuster adapted to be interposed between a brake operating shaft and a brake actuating rod, said brake adjuster including: an actuating arm assemblage comprising a body portion and an elongate actuating arm integral with the body portion, a drive shaft bore in said body portion receiving a drive shaft therewithin for rotation, a connecting shaft bore in said body portion extending at right angles to the drive shaft bore and communicating therewith at one end of the connecting shaft bore and centrally of the drive shaft bore through an opening, a connecting shaft rotatably received in said body portion and connecting shaft bore, the brake actuating rod pivotally connected to the elongate actuating arm and a link rod connected at its other end to the drive shaft through a crank arm, a worm freely rotatably mounted on the drive shaft and a gear fixed to the connecting shaft, said worm engageable with said gear through said opening so rotation of the drive shaft will rotate the connecting shaft when the worm is fixed to the drive shaft, a first clutch means communicating between said drive shaft and said worm, said first clutch means operable on rotation of said drive shaft in a first direction to couple the worm and drive shaft together for rotation, one with the other, and on rotation of the drive shaft in the opposite direction to free the worm and drive shaft for rotation of the latter without the former, and a second clutch means communicating between said worm and said body portion, said second clutch means operable on rotation of said drive shaft in said first direction to free the worm and body portion from one another to permit rotation of the drive shaft and worm together and on rotation of the drive shaft in the opposite direction to couple the worm and body portion together, whereby to prevent rotation of the worm with the drive shaft.
Claim 13
Dependent Claim
326 words
In an automatic brake adjuster adapted to be interposed between a brake operating shaft and a brake actuating rod, said brake adjuster including: an actuating arm assemblage comprising a body portion and an elongate actuating arm integral with the body portion, a drive shaft bore in said body portion receiving a drive shaft therewithin for rotation, a connecting shaft bore in said body portion extending at right angles to the drive shaft bore and communicating therewith at one end of the connecting shaft bore and centrally of the drive shaft bore through an opening, a connecting shaft rotatably received in said body portion and connecting shaft bore, the brake actuating rod pivotally connected to the elongate actuating arm and a link rod connected at its other end to the drive shaft through a crank arm, a worm freely rotatably mounted on the drive shaft and a gear fixed to the connecting shaft, said worm engageable with said gear through said opening so rotation of the drive shaft will rotate the connecting shaft when the worm is fixed to the drive shaft, a first clutch means communicating between said drive shaft and said worm, said first clutch means operable on rotation of said drive shaft in a first direction to couple the worm and drive shaft together for rotation, one with the other, and on rotation of the drive shaft in the opposite direction to free the worm and drive shaft for rotation of the latter without the former, and a second clutch means communicating between said worm and said body portion, said second clutch means operable on rotation of said drive shaft in said first direction to free the worm and body portion from one another to permit rotation of the drive shaft and worm together and on rotation of the drive shaft in the opposite direction to couple the worm and body portion together, whereby to prevent rotation of the worm with the drive shaft.
Claim 14
Dependent Claim
291 words
In a slack adjusting mechanism for vehicle brakes, an actuating arm assemblage comprising a body portion and an elongate actuating arm integral with the body portion, a first bore in the body portion, an internally splined first worm gear rotatably mounted in said bore and adapted to receive therethrough a brake-actuating cam shaft, the actuating arm being adapted for connection with means for rocking the housing in application and release of the brake and the associated brake-actuating cam shaft, a second bore in the body portion extending at right angles to the turning axis of the worm gear and opening at one end thereof intO the first bore, a connecting shaft rotatably mounted in the second bore and carrying a first worm thereon having driving connection trhough the first named opening with said first worm gear, a third bore in the body portion extending across the other end of the second bore and opening thereinto, a second gear mounted on the connecting shaft with the threads thereof extending into the second named opening, a drive shaft rotatably mounted in the third bore carrying a second worm thereon having driving connection with the second gear through the second mentioned opening, and manual adjustment means for disengagement of the second gear with the second worm and rotation of the connecting shaft, whereby to rotate the first worm gear and adjust the brake, said manual adjustment means accessible from the exterior of the body portion, the manual adjustment means including: the second gear slidably mounted on said connecting shaft, removable retaining means normally holding the second gear in engagement with the second worm, and engaging means on said connecting shaft outboard of the second gear for engagement and manual rotation of said connecting shaft.
Claim 15
Dependent Claim
291 words
In a slack adjusting mechanism for vehicle brakes, an actuating arm assemblage comprising a body portion and an elongate actuating arm integral with the body portion, a first bore in the body portion, an internally splined first worm gear rotatably mounted in said bore and adapted to receive therethrough a brake-actuating cam shaft, the actuating arm being adapted for connection with means for rocking the housing in application and release of the brake and the associated brake-actuating cam shaft, a second bore in the body portion extending at right angles to the turning axis of the worm gear and opening at one end thereof intO the first bore, a connecting shaft rotatably mounted in the second bore and carrying a first worm thereon having driving connection trhough the first named opening with said first worm gear, a third bore in the body portion extending across the other end of the second bore and opening thereinto, a second gear mounted on the connecting shaft with the threads thereof extending into the second named opening, a drive shaft rotatably mounted in the third bore carrying a second worm thereon having driving connection with the second gear through the second mentioned opening, and manual adjustment means for disengagement of the second gear with the second worm and rotation of the connecting shaft, whereby to rotate the first worm gear and adjust the brake, said manual adjustment means accessible from the exterior of the body portion, the manual adjustment means including: the second gear slidably mounted on said connecting shaft, removable retaining means normally holding the second gear in engagement with the second worm, and engaging means on said connecting shaft outboard of the second gear for engagement and manual rotation of said connecting shaft.
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) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |