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 synchronizing ring for a synchronizer having an inner ring. The synchronizing ring is designed to be arranged outside of and to abut against the inner ring for achieving friction between an outer surface of the inner ring and an inner surface of the synchronizing ring during synchronization. The synchronizing ring has a plurality of through holes extending from the inner surface to an outer surface of the synchronizing ring for evacuation of oil from the interface between the inner ring and the synchronizing ring.

A sliding sleeve (1) of a vehicle transmission synchronization, wherein the tooth flanks (10) of the toothing (2) of the sliding sleeve (1) are surface-treated for enhanced friction.

A claw-type gearshift includes a sliding sleeve and a clutch body of a speed change gear, in which the sliding sleeve can engage. A blocking ring having an external toothing is arranged axially between the hub body and the clutch body and is fixed to the hub body such that it is rotatable in relation to the sliding sleeve by a certain degree in the circumferential direction between a release position and two locking positions. The blocking ring has a plurality of axially resilient tabs which are directed radially inward and which bear against the hub body and limit the movement of the blocking ring relative to the hub body in the circumferential direction, and a ring portion which is arranged radially outside of the tabs and which includes a friction surface that rests permanently against a mating friction surface on the clutch body.

A claw-type gearshift has a sliding sleeve which is adapted to be axially displaced on a hub body and a clutch body of a speed change gear. The hub body has at least one thrust piece arranged thereon which includes a friction surface that cooperates with a mating friction surface on the clutch body, the at least one thrust piece being displaceable in the circumferential direction between a release position and two locking positions that are located on either side of the release position. A first locking structure on the at least one thrust piece cooperates with a second locking structure on the internal toothing of the sliding sleeve. The locking structures are configured such that in each of the locking positions, the locking structures rest against each other such that a further axial movement of the sliding sleeve is blocked. For shifting a gear, a difference in speed between the clutch body and the hub body is reduced.

A method for motion control of a shift sleeve in a stepped gear transmission during a synchronization and gear engagement sequence for avoiding gear teeth interference, wherein the stepped gear transmission includes an axially displaceable shift sleeve arranged on and rotationally secured to a shaft, and a constant mesh gear wheel arranged on and rotatable relative to said shaft.

Various methods and systems are provided for a multi-speed electric axle assembly. The multi-speed electric axle assembly includes a grounding plate with an outer interface coupled to a housing interface and an inner stepped splined interface designed to selectively mate with a clutch sleeve. In the assembly, the inner stepped splined interface includes a plurality of steps that each include a first side that perpendicularly intersects a second side and the first side of each step in the inner stepped splined interface includes a clearance between the first side and a stepped surface of the clutch sleeve.

A synchronizer for mechanical transmissions having a phasing system configured so as to include a plurality of first cavities on an internal cylindrical surface of a rim of a hub, the hub torsionally connected with a transmission shaft, forming the external teeth of the hub and, for each of the first cavities, either a tooth which radially protrudes from an external cylindrical surface of a synchronizing ring of the synchronizer and is arranged to engage in the first cavity, or a connecting pin arranged to engage on one side the first cavity and on the other a respective second cavity on the external cylindrical surface, wherein the first cavities have an arc- or round-shaped cross-section.

A method for motion control of a shift sleeve in a stepped gear transmission during a synchronization and gear engagement sequence for avoiding gear teeth interference, wherein the stepped gear transmission includes an axially displaceable shift sleeve arranged on and rotationally secured to a shaft, and a constant mesh gear wheel arranged on and rotatable relative to said shaft.

A complex synchronizer may include a first connection gear and a second connection gear that are fixed to a shaft; a first external gear having a first sleeve, which can engage with the first connection gear by sliding along the shaft, and rotatably mounted on the shaft; a second external gear having a second sleeve, which can engage with the second connection gear by sliding along the shaft, and rotatably mounted on the shaft; and an intermediate gear being able to connect or disconnect the first sleeve and the second sleeve, depending on axial sliding states of the first sleeve and the second sleeve.