A synchronizer mechanism for synchronizing the rotation of gears between a power input shaft and a power output shaft in a manual transmission includes a hub and a synchronizer sleeve disposed about the hub and moveable relative thereto into and out of engagement with adjacent gears to synchronize the rotation of the adjacent gears with the rotation of the power input shaft. An indexing mechanism is employed for indexing the synchronizer sleeve into and out of engagement with adjacent gears. The indexing mechanism includes a retaining mechanism and a detent portion having a main synchronization detent and at least one second synchronization detent disposed laterally adjacent the main synchronization detent. The main synchronization detent causes an intermediate clutch ring to contact a cylindrical cone portion on a gear and begin the change in angular velocity of the gear and to begin the synchronization sequence of the mechanism at a first time. The second synchronization detent causes the intermediate clutch ring to contact a cylindrical cone portion on a gear and change the angular velocity of the gear and synchronizer mechanism at a second time reducing the minor speed difference between the gear and synchronizer sleeve caused by loss of synchronization between the time of sleeve and ring indexing and initial engagement contact of the sleeve to the clutch teeth of the gear.

A synchronizer may have a hub, an engagement sleeve, a pair of engagement ring gears, a pair of synchronizing rings and a pre-synchronizing system interposed between the hub and the engagement sleeve. The pre-synchronizing system may have a single elastic ring which is axially interposed between the synchronizing rings, is drivingly connected with the engagement sleeve in the axial sliding movement relative to the hub and is at least partially received in an internal annular groove of the engagement sleeve.

A synchronizer may have a hub, an engagement sleeve, a pair of engagement ring gears, a pair of synchronizing rings and a pre-synchronizing system interposed between the hub and the engagement sleeve. The pre-synchronizing system may have a single elastic ring which is axially interposed between the synchronizing rings, is drivingly connected with the engagement sleeve in the axial sliding movement relative to the hub and is at least partially received in an internal annular groove of the engagement sleeve.

A control device of an internal speed change device of a wheel hub for clutching operation includes a rod; a lever installed on the rod; the lever being connected to a controlling claw sliding block; an electric sliding block installed on a lever sleeve; the lever sleeve serving to receive a back end of the lever; an electric bushing located at an outer side of the lever sleeve; a controlling ring located at an outer side of the electric bushing; and wherein force of attraction or repulsion between the controlling ring and the electric sliding block drives the electric sliding block to rotate or move axially so as to drive the lever to move forwards or backwards axially; and moving of the lever drives the controlling claw sliding block to control clutching of the internal speed change device.

A control device of an internal speed change device of a wheel hub for clutching operation includes a rod; a lever installed on the rod; the lever being connected to a controlling claw sliding block; an electric sliding block installed on a lever sleeve; the lever sleeve serving to receive a back end of the lever; an electric bushing located at an outer side of the lever sleeve; a controlling ring located at an outer side of the electric bushing; and wherein force of attraction or repulsion between the controlling ring and the electric sliding block drives the electric sliding block to rotate or move axially so as to drive the lever to move forwards or backwards axially; and moving of the lever drives the controlling claw sliding block to control clutching of the internal speed change device.

A synchronizer of a transmission may include bottom key disposed on a hub to be slidable in a radial direction of the hub; a top key disposed radially outside the bottom key to be slidable in an axial direction of the hub; a sleeve disposed outside the hub and sliding in the axial direction to slide the top key in the axial direction to press a synchro-ring; a key spring disposed between the bottom key and the hub to press the bottom key and the top key toward an internal side of the sleeve; and a motion converting portion converting relative motion generated in a circumferential direction of the hub between the top key and the bottom key into axial relative motion of the top key to the bottom key toward the synchro-ring.

A synchronizing device, for a vehicle gearbox, with a synchronizer body which can be mounted rotationally fixedly on an axial shaft, and a shift sleeve which is connected rotationally fixedly to the synchronizer body and can be moved axially along an outer periphery of the synchronizer body and which, to perform a synchronizing process, can be brought from a neutral position into rotationally fixed engagement in a first shift phase with an axially displaceable synchronizer ring and in a second shift phase with a clutch body adjacent to the synchronizer ring. During the first shift phase, the synchronizer ring can be moved in the direction of the adjacent clutch body by the shift sleeve using pressure pads arranged axially displaceably in the synchronizer body, and hence can be brought into frictional engagement with the adjacent clutch body for the purpose of pre-synchronization.

A synchronizer of a transmission may include bottom key disposed on a hub to be slidable in a radial direction of the hub; a top key disposed radially outside the bottom key to be slidable in an axial direction of the hub; a sleeve disposed outside the hub and sliding in the axial direction to slide the top key in the axial direction to press a synchro-ring; a key spring disposed between the bottom key and the hub to press the bottom key and the top key toward an internal side of the sleeve; and a motion converting portion converting relative motion generated in a circumferential direction of the hub between the top key and the bottom key into axial relative motion of the top key to the bottom key toward the synchro-ring.

A synchronizing device is provided for synchronizing a first rotatable part with a second rotatable part adjacent to the first rotatable part. The synchronizing device includes a first part provided with an engaging sleeve and a second part provided with a synchronizer ring. The synchronizing device has at least one positioning resilient member which is arranged to act upon the synchronizer ring and the second part, in order to allow a design with few parts and also to resynchronize the synchronizing ring with the second part. A transmission including such a synchronizing device is also provided.

A synchronizing device, for a vehicle gearbox, with a synchronizer body which can be mounted rotationally fixedly on an axial shaft, and a shift sleeve which is connected rotationally fixedly to the synchronizer body and can be moved axially along an outer periphery of the synchronizer body and which, to perform a synchronizing process, can be brought from a neutral position into rotationally fixed engagement in a first shift phase with an axially displaceable synchronizer ring and in a second shift phase with a clutch body adjacent to the synchronizer ring. During the first shift phase, the synchronizer ring can be moved in the direction of the adjacent clutch body by the shift sleeve using pressure pads arranged axially displaceably in the synchronizer body, and hence can be brought into frictional engagement with the adjacent clutch body for the purpose of pre-synchronization.