US3866488A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manually operated shift assembly with restraining action for shifting to reverse
Assignee: Toyota Motor Corp
•
Filing: 1973-10-29
•
Granted: 1975-02-18
•
Expires: 1993-10-29
Abstract
Abstract In a manually operable shift assembly a plurality of fork shafts are arranged within a gear case and each fork shaft is axially displaceable between two different gear positions by a gearshift lever which engages a recess within the fork shaft. One of the fork shafts is axially movable between a forward gear position and a reverse gear position and the fork shaft alongside it is movable between two forward gear positions. To prevent accidental engagement in the reverse gear position when shifting into or out of its associated forward gear position a limiting or restricting action is provided which must be overcome before movement into the reverse gear position can be attained. In one embodiment, the restricting action is provided between a plate mounted on the gearshift lever and a spring biased member arranged within the gear case. In another embodiment the limiting action is provided by spring biased pins located in the recess in the fork shaft. Additionally, the shifting movement can be effected by means of an intermediate rod and lever assembly disposed between the gearshift lever and the fork shaft with the restricting action afforded between the lever on the intermediate rod and a spring biased pin positioned in the gear case at a location spaced from the fork shaft.
Inventors
- 👤 Tadao Nakata
- 👤 Hideaki Mizutani
- 👤 Shinichi Ito
- 👤 Mitsuhiko Okada
- 👤 Nobuaki Katayama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:11
CPC Classifications
F; F16; F16H; F16H59/00; F16H59/02; F16H59/04; F16H59/042; F16H61/00; F16H61/18; F16H63/00; F16H63/02; F16H63/08; F16H63/20; F16H2061/185; F16H63/30; F16H2063/3086; F16H61/24; F16H63/34; F16H63/3408; Y; Y10; Y10T; Y10T74/00; Y10T74/20; Y10T74/20012; Y10T74/20018; Y10T74/20085; Y10T74/20104; Y10T74/20116
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
509 words
In a transmission including a gear case arranged to contain change gears, at least two fork shaft positioned within said gear case in side-by-side relationship and each arranged to be axially displaceable in the opposite directions from a neutral position for effecting a speed change in the change gears, each said fork shaft having a recess with the recesses arranged in side-by-side relationship in the neutral position, manually operable first means mounted in said gear case and arranged for selective engagement within said recesses in said fork shaft for selecting one of said fork shafts in the neutral position for shifting from the neutral position in the axial direction of the selected fork shaft for changing gears, wherein the improvement comprises interlocking means for preventing said two fork shafts from being axially displaced at the same time, a first one of said two fork shafts providing a forward gear position and a reverse gear position disposed in spaced relationship in the axial direction of the shaft on the opposite sides of the neutral position thereof, the second one of said two fork shafts providing two forward gear positions arranged in spaced relationship in the axial Direction of the fork shaft on the opposite sides of the neutral position, said recess in said first fork shaft having a pari of opposed sides spaced apart in the axial displacing direction with one side located closer to the reverse gear position and the other side located closer to the forward gear position, said recess in said second fork shaft having a pair of opposed sides spaced apart in the axially displacing direction with one of said sides thereof aligned in the neutral position with the reverse shift position side of the recess in said first fork shaft when it is in the neutral position, said one of said sides extending toward the recess in said first fork shaft beyond the end of the other said side thereof closer to the recess in said first fork shaft, second means in operative association with said first means for affording a limitation on the movement of said first means from the recess in said second fork shaft into the recess in said first fork shaft so that in addition to the effort required for axial displacement needed for movement from the neutral position into the forward gear position of said first fork shaft at least one restricting action is provided to be overcome for displacing said first means for shifting from the neutral position to the reverse gear position of said first fork shaft, and the restricting action of said second means limiting the displacement of said first means into the recess in said first fork shaft so that said first means contacts said extension on the one said side of the recess in said second fork shaft and said interlocking means operates to prevent said first fork shaft from being displaced into the reverse gear position until the restricting action is overcome and said first means is moved out of contact with said extension.
Claim 2
Dependent Claim
509 words
In a transmission including a gear case arranged to contain change gears, at least two fork shaft positioned within said gear case in side-by-side relationship and each arranged to be axially displaceable in the opposite directions from a neutral position for effecting a speed change in the change gears, each said fork shaft having a recess with the recesses arranged in side-by-side relationship in the neutral position, manually operable first means mounted in said gear case and arranged for selective engagement within said recesses in said fork shaft for selecting one of said fork shafts in the neutral position for shifting from the neutral position in the axial direction of the selected fork shaft for changing gears, wherein the improvement comprises interlocking means for preventing said two fork shafts from being axially displaced at the same time, a first one of said two fork shafts providing a forward gear position and a reverse gear position disposed in spaced relationship in the axial direction of the shaft on the opposite sides of the neutral position thereof, the second one of said two fork shafts providing two forward gear positions arranged in spaced relationship in the axial Direction of the fork shaft on the opposite sides of the neutral position, said recess in said first fork shaft having a pari of opposed sides spaced apart in the axial displacing direction with one side located closer to the reverse gear position and the other side located closer to the forward gear position, said recess in said second fork shaft having a pair of opposed sides spaced apart in the axially displacing direction with one of said sides thereof aligned in the neutral position with the reverse shift position side of the recess in said first fork shaft when it is in the neutral position, said one of said sides extending toward the recess in said first fork shaft beyond the end of the other said side thereof closer to the recess in said first fork shaft, second means in operative association with said first means for affording a limitation on the movement of said first means from the recess in said second fork shaft into the recess in said first fork shaft so that in addition to the effort required for axial displacement needed for movement from the neutral position into the forward gear position of said first fork shaft at least one restricting action is provided to be overcome for displacing said first means for shifting from the neutral position to the reverse gear position of said first fork shaft, and the restricting action of said second means limiting the displacement of said first means into the recess in said first fork shaft so that said first means contacts said extension on the one said side of the recess in said second fork shaft and said interlocking means operates to prevent said first fork shaft from being displaced into the reverse gear position until the restricting action is overcome and said first means is moved out of contact with said extension.
Claim 3
Dependent Claim
35 words
In a transmission, as set forth in claim 1, wherein a select return device is provided for keeping said first means in engagement with the recess in said second fork shaft in the neutral position.
Claim 4
Dependent Claim
93 words
In a transmission, as set forth in claim 1, wherein said first means comprises a gearshift lever, said second means includes a plate positioned within said gear case and mounted on said gearshift lever for displacement with said gearshift lever in the selecting action, and a restricting means mounted in said gear case and disposed in a contacting engagement with and in the path of movement of said plate as it is moved by said gearshift lever from the recess in said second fork shaft to the recess in said first fork shaft.
Claim 5
Dependent Claim
62 words
In a transmission, as set forth in claim 3, wherein said plate includes a projection thereon facing toward and disposed in contact with said restricting means as said gearshift lever is moved from said recess in said second fork shaft to said recess in said first fork shaft, and said restricting means includes a ball spring biased into contact with said plate.
Claim 6
Dependent Claim
163 words
In a transmission, as set forth in claim 4, wherein said projection on said plate comprises a first step extending outwardly from said plate toward said restricting means and a second step extending from said first step and projecting from said first step toward said restricting means so that the end of said plate from which said projection extends and the side of said first step extending from said plate contacts said ball as said second fork shaft is in the neutral position and said first step provides the first restricting action to be overcome for displacement of said first said fork shaft for achieving the forward gear position and the surface of said first step and the side of said second step projecting from said first step toward said restricting means provides the second restricting action to be overcome for displacement of said first fork shaft for achieving the reverse gear position from the neutral position after overcoming the first restricting action.
Claim 7
Dependent Claim
155 words
In a transmission, as set forth in claim 1, wherein said first means comprises a gearshift lever having a finger at its end arrangEd to engage selectively into the recesses in said fork shafts and said second means comprising a spring biased pin mounted in the recess of said first fork shaft and arranged to be displaced against the spring bias in the direction of movement from the recess in said second fork shaft into the recess in said first fork shaft, said pin having an end surface which has a first position arranged to contact said finger of said gearshift in position for shifting said first fork shaft into the forward gear position and a second position displaced in the direction between the recesses for shifting said first fork shaft into the reverse gear position with said pin being displaced against the spring bias thereon for movement from the first to the second position.
Claim 8
Dependent Claim
46 words
In a transmission, as set forth in claim 6, wherein a spring biased ball is mounted in said first fork shaft, and said pin having a recess in the side thereof arranged to receive the spring biased ball for holding said pin in the first position.
Claim 9
Dependent Claim
140 words
In a transmission, as set forth in claim 1, wherein said first means comprises a gearshift lever having a manually operable handle portion accessible on the exterior of said gear case and a finger portion spaced from said handle portion and located within said gear case, a housing positioned within said gear case and secured to said finger portion and displaceable with said gearshift lever, an intermediate rod fixed at one end to said housing and extending therefrom through said gear case transversely of the direction of said gearshift lever, a lever fixed to said intermediate rod at a position spaced axially along said intermediate rod from said housing, said lever displaceable with said intermediate rod in response to the displacement of said housing by said gearshift lever, and said lever being displaceable between said recesses in said fork shafts.
Claim 10
Dependent Claim
76 words
In a transmission, as set forth in claim 8, wherein a select return device is mounted in said gear case and is arranged in contact with said housing for biasing said housing into the neutral position of said gearshift lever, said select return device comprises a pair of spring biased pins mounted in said gear case and disposed in contact with opposite sides of said housing and arranged to return said housing to the neutral position.
Claim 11
Dependent Claim
68 words
In a transmission, as set forth in claim 8, wherein said second means comprises a spring biased pin mounted in the recess of said first fork shaft and biased into the path of said lever of said intermediate rod as it moves into said recess so that said pin affords the restricting action required to be overcome for achieving the reverse gear position of said first fork shaft.
Claim 12
Dependent Claim
80 words
In a transmission, as set forth in claim 8, wherein said second means comprises a spring biased pin mounted in said gear case and extending into contacting engagement with said lever at a position on said lever spaced from the portion thereof engageable within the recesses in said fork shafts, and the portion of said lever contacting said pin arranged to provide the restricting action required to be overcome for achieving the reverse gear position of said first fork shaft.
Claim 13
Dependent Claim
29 words
In a transmission, as set forth in claim 11, wherein the portion of said lever contacting said pin comprises a cam-like surface arranged in the path of said pin.
Claim 14
Dependent Claim
52 words
In a transmission, as set forth in claim 11, wherein the portion of said lever contacting said pin comprises a recess in said lever with the end of the recess arranged to contact said pin when said first fork shaft is in the neutral position for movement into the reverse gear position.
References Cited (Backward Citations)
US1831194A
Cited
US1951876A
Cited
US2178061A
Cited
US3043413A
Cited
US3192788A
Cited
US3269208A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-17 | 1978-08-19 | 1979-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-17 | 1982-08-19 | 1983-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-17 | 1986-08-19 | 1987-02-18 | $7700.00 | Window Closed / Lapsed |