Abstract: Disclosed herein is a lubrication mechanism in a parallel dual-shaft type gear transmission which includes intermediate plate arranged between a transmission case and an extension housing and an output shaft and a counter shaft arranged in parallel relation in the transmission case. The lubrication mechanism comprises an oil guiding rib formed along an outer circumference of a small diametrical counter gear arranged in the vicinity of the intermediate plate. With this arrangement, a lubricating oil may be sufficiently supplied to desired areas in the gear transmission by means of a small diametrical counter gear.

Abstract: Disclosed herein in a mount structure where a shift lever retainer for spherically supporting a shift lever is mounted through a vibration damping member to a transmission case by a bolt, a vibration damping structure comprising a stopper means for preventing horizontal and vertical deformations of the vibration damping member greater than a predetermined amount. With this arrangement, there is no possibility that rigid feeling in operating of the shift lever is decreased, that is, shift feeling is deteriorated. Further, vibration of the shift lever and associated noise may be greatly reduced.

Abstract: An apparatus for preventing gear buzzing in shifting to reverse which is applied to a manual transmission having a plurality of forward gear means provided with synchronous meshing mechanisms and a reverse gear means provided with a selective sliding-gear meshing mechanism driven through a reverse idler gear. An inclined guide surface is formed on a forward shift head, and a projection is formed on a shift-and-select lever. The projection is brought into contact with and slides on the inclined guide surface. A clearance is provided between the forward shift head and an interlocking mechanism so as to permit slight shifting movement of the shift head.

Abstract: A reverse shift mechanism for a manual automotive transmission of the type having a reverse idler gear which is movable such as to selectively form a reverse gear train. The reverse shift mechanism includes a reverse shift arm carrying a shoe which engages with a circumferential groove in the reverse idler gear so as to push the same gear. An end of the reverse shift arm adjacent the reverse idler gear is formed with a hole, while the shoe has an end which is shaped to fit in the hole. In the assembly, end of the shoe fits in the hole formed in the reverse shift arm so that the shoe is prevented from coming off. After assembly, the shoe is clamped between the groove formed in the reverse idler gear and the hole in the reverse shift arm so that it is held in place.

Abstract: A transmission unit comprises a differential gear unit having a pair of side-journals rotatably supported by a pair of axially spaced side-bearings carried on a pair of carrier portions of a casing for the transmission unit, a pair of wheel axles extending outwardly through the respective side-journals from the differential gear unit in an opposite direction and surrounded by a pair of annular seal members carried on the respective carrier portions, a pair of annular shim plates interposed between each of the carrier portions and each of the side-bearings, and a pair of oil passages for leading lubricating oil into a pair of annular side-spaces formed around each of the wheel axles between the respective side-bearings and the respective seal members.

Abstract: A detent mechanism associated with a selector mechanism for change-speed gears in a manual transmission which includes a shift-and-select shaft axially slidably and rotatably assembled within a transmission housing and being linked with a manual shift lever to be axially moved in selecting operation of the shift lever and to be rotated in shifting operation of the shift lever. The detent mechanism comprises a casing rotatable on the shaft but axially fixed to the same, the casing being formed at its inner wall with a plurality of equiangularly spaced axial detent grooves in parallel with the axis of the shaft, a spring loaded follower element radially movable within a portion of the shaft and being selectively retained in the axial detent grooves of the casing under resilient load, and a guide pin secured to the transmission housing and being slidably engaged with an axial slot of the casing.

Abstract: A transmission manipulation device for a manual transmission includes a single main fork shaft provided in a main chamber of a transmission case, a plurality of shift forks axially movably mounted on the main fork shaft and associated with respective transmission clutch mechanisms, a shift and select lever shaft axially movably and rotatably provided in the main chamber to extend in the direction perpendicular to the main fork shaft, an auxiliary fork shaft provided in an auxiliary chamber of the transmission case to extend in parallel with the main fork shaft, and a shift fork fixed to the auxiliary fork shaft and associated with a transmission clutch mechanism in the auxiliary chamber. The shift and select lever shaft has a projection which is selectively engageable with the engaging portion of any one of the shift forks as the lever shaft is moved in the axial direction and rotation of the lever shaft causes movement of any one of the shift forks in the axial direction of the main fork shaft.

Abstract: Disclosed is an interlocking construction for manual transmission manipulation device. The interlocking construction comprises an interlocking plate rotatably provided on a shift and select lever shaft but prevented from rotating with respect to a case, so that when a second projection of the lever shaft engages an engaging portion of a first shift head, the interlocking plate is engageable with the engaging portions of the shift forks on a first fork shaft which are not engaged by a first projection, as well as with the engaging portion of a second shift head, whereas, when the second projection does not engage with the first shift head, the interlocking plate is engageable with the engaging portions of all shift forks on the first fork shaft, as well as the engaging portion of the first shift head.

Abstract: A gear assembly includes a pair of driving and driven helical gears permanently in meshing engagement with each other to provide a torque transmission therebetween, and an additional plate-like gear formed at its outer periphery with helical teeth the helix angle of which is different from each helix angle of respective teeth of the helical gears and being resiliently deformable in an axial direction. The additional plate-like gear is coaxially and rotatably mounted in place on a hub portion of the driven helical gear and meshed at its two teeth with one tooth of the driving gear such that the additional plate-like gear is resiliently in contact with one end face of the driven gear at a place radially opposite to the meshed portion of the helical gears.

Abstract: A device for preventing reverse gear buzzing in a manual transmission comprising a transmission casing, a forward speeds unit provided with a plurality of synchromesh mechanisms, a reverse unit provided with a selective sliding mesh mechanism of a reverse idler gear and having a reverse shift head, a shift-and-select lever shaft, an inner lever attached to the shift-and-select lever shaft, an interlocking plate loosely mounted to the shift-and-select lever shaft and holding the inner lever at both ends, said interlocking plate serving to hold immovably at the neutral position the remaining shift heads other than one of said shift heads which is selected by the select operation of the inner lever, a locking means fixed to the transmission casing and adapted to hold the interlocking plate in such a manner that the interlocking plate is permitted to axially move together with the lever shaft and to rotate relative to the lever shaft, a stopper formed on the shift head adjacent to the reverse shift head and adapt

Abstract: In combination with a manual transmission including a transmission casing, a forward speeds unit provided with a plurality of synchromesh mechanisms, a reverse unit provided with a selective sliding mesh mechanism, a lever shaft, an inner lever, an interlocking plate relatively rotatably mounted to the lever shaft and holding the inner lever at both ends, said interlocking plate serving to hold immovable at the neutral position the remaining shift heads other than one of the shift heads which is selected by the select operation of the inner lever; a device for preventing reverse gear buzzing comprises first front and rear engaging members of the forward speed shift head adjacent to the reverse shift head for releasably engaging with the inner lever when the inner lever is selected into the reverse position, a second front and rear engaging members provided on the reverse shift head, first means for contacting with the interlocking plate at the reverse select position, moving the reverse shift head and the for

Abstract: Disclosed is a transmission manipulation device for a transmission which is improved in eliminating abnormal circumferential wear of a shift fork due to pressure contact with the sleeve of a clutch mechanism incorporated in the transmission. The device has a shift and select lever shaft provided with a first retaining portion and a second retaining portion. The second retaining portion is engageable with the engaging portion of the first shift head only when a first retaining portion engages with the engaging portion of one of a plurality of shift forks on the lever shaft. When the shift and select lever shaft is rotated after axial movement against the resilient force of a resilient member, the second retaining portion is retained by the first shift head to prevent axial movement of the lever shaft due to the reactional force of the resilient member.

Abstract: Disclosed herein is a transmission mechanism in a manual transmission which may eliminate unsmooth movement of the shift fork along the fork shaft during a shift operation so as to improve the feeling of shift-and-select operation. According to the present invention, the shift fork which is selected by the axial movement of the shift-and-select lever shaft is effective to move together with the fork shaft at substantially same speed by the rotation of the lever shaft. For this purpose, the fork shaft is axially movably mounted on the transmission casing and is connected to the lever shaft.

Abstract: The application discloses a method of assembling gears, transmission shafts, fork shift shaft and associated component parts of a 5-speed transmission for a vehicle. The fifth-speed gear and the hub therefor are designed to be installed outside the end of the transmission case which is remote from the end thereof secured to a clutch housing. After first to fourth-speed gears and associated component parts are mounted on the transmission shafts which have already been mounted at their one ends to bearings mounted on the clutch housing, the transmission case is moved over the transmission shafts, the gears and the associated component parts thereof in such a manner that an open end of the transmission case is directed toward the clutch housing until the open end of the transmission case reaches the clutch housing and the other ends of the transmission shafts are inserted into and project through bearings mounted on the other end of the transmission case.