Synchronizer re-energization for improved cold shift comfort

Patent metadata

Field	Value
Publication number	US-9719564-B2
Application number	US-64478309-A
Country	US
Kind code	B2
Filing date	Dec 22, 2009
Priority date	Dec 22, 2009
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

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.

First claim

What is claimed is:

1. A method of using a synchronizer arrangement for a manual transmission having a first shaft, a second shaft, and a plurality of gears carried on said first and second shafts, said plurality of gears adapted to be intermeshed for transferring power therebetween, said method comprising:
moving a synchronizer sleeve that is slidably coupled to a hub fixed for rotation on one of the first or second shafts by axially moving the synchronizer sleeve along said hub in a first direction from a neutral position to a first operative position whereby said synchronizer sleeve operatively couples with a first gear of said plurality of gears; and
synchronizing the rotation of said synchronizer sleeve with the rotation of said first gear at first and second times during engagement of the first gear.

2. The method of claim 1 , further comprising:
moving said synchronizer sleeve by axially moving the synchronizer sleeve along said hub in a second direction from said neutral position to a second operative position whereby said synchronizer sleeve operatively couples with a second gear of said plurality of gears; and
synchronizing the rotation of said synchronizer sleeve with the rotation of said second gear at first and second times during engagement of the second gear.

3. The method of claim 2 , further comprising using an indexing mechanism in order to synchronize the rotation of said synchronizer sleeve with the rotation of said first and said second gears, said indexing mechanism comprising:
a plurality of retaining mechanisms radially located along the outer surface of said hub; and
a plurality of detent portions radially located along the inner surface of said synchronizer sleeve and disposed opposite to said plurality of retaining mechanisms.

4. The method of claim 3 , wherein using an indexing mechanism includes, for each of said plurality of detent portions:
engaging a main synchronization detent laterally centered on said synchronization sleeve; and
engaging at least one of a pair of second synchronization detents, wherein a first detent of said pair of second synchronization detents is disposed adjacent a first lateral portion of said main synchronization detent and a second detent of said pair of second synchronization detents is disposed adjacent a second lateral portion of said main synchronization detent opposite to said first detent of said pair of second synchronization detents.

5. The method of claim 3 , wherein using an indexing mechanism includes engaging at least some of the plurality of detent portions via at least some of the plurality of retaining mechanisms, wherein each of said plurality of retaining mechanisms further comprises:
a slot extending radially in said hub;
a spring disposed in said slot;
a strut at least partially disposed in said slot; and
a ball at least partially disposed in said slot and at least partially surrounded by said strut, wherein said spring forces said ball outwards from said slot and into contact with a detent of said plurality of detent portions.

6. The method of claim 3 , further comprising engaging said first gear using a first intermediate clutch ring and engaging said second gear using a second intermediate clutch ring, wherein
said first intermediate clutch ring is between said first gear and said synchronization sleeve; and
said second intermediate clutch ring is between said second gear and said synchronization sleeve; and
wherein said first intermediate clutch ring and said second intermediate clutch ring further comprise a conical inner surface, said first gear and said second gear each further comprising a cylindrical cone portion, said conical inner surface of said first intermediate clutch ring being configured to mate with said cylindrical cone portion of said first gear, said conical inner surface of said second intermediate clutch ring being configured to mate with said cylindrical cone portion of said second gear.

7. The method of claim 1 , further comprising using an indexing mechanism in order to synchronize the rotation of said synchronizer sleeve with the rotation of said first gear, said indexing mechanism comprising:
a plurality of retaining mechanisms radially located along the outer surface of said hub; and
a plurality of detent portions radially located along the inner surface of said synchronizer sleeve and disposed opposite to said plurality of retaining mechanisms.

8. The method of claim 7 , wherein using an indexing mechanism includes, for each of said plurality of detent portions:
engaging a main synchronization detent laterally centered on said synchronization sleeve; and
engaging a second synchronization detent, wherein said second synchronization detent is disposed adjacent a lateral portion of said main synchronization detent.

9. The method of claim 7 , wherein using an indexing mechanism includes engaging at least some of the plurality of detent portions via at least some of the plurality of retaining mechanisms, wherein each of said plurality of retaining mechanisms further comprises:
a slot extending radially in said hub;
a spring disposed in said slot;
a strut at least partially disposed in said slot; and
a ball at least partially disposed in said slot and at least partially surrounded by said strut, wherein said spring forces said ball outwards from said slot and into contact with a detent of said plurality of detent portions.

10. The method of claim 7 , further comprising engaging said first gear using a first intermediate clutch ring, wherein
said first intermediate clutch ring further comprises a conical inner surface;
said first gear further comprises a cylindrical cone portion; and
wherein said conical inner surface of said first intermediate clutch ring is configured to mate with said cylindrical cone portion of said first gear.

11. A method of using a manual transmission comprising
a power input shaft,
a power output shaft,
a plurality of gears carried on said power input and power output shafts and adapted to be intermeshed therebetween for transferring power from said power input shaft to said power output shaft, and
a synchronizer mechanism including a hub, an intermediate clutch ring and a synchronizer sleeve disposed about said hub, the method comprising:
moving said synchronizer sleeve relative to said hub into and out of engagement with adjacent gears to synchronize the rotation of said adjacent gears with the rotation of said synchronizer mechanism; and
synchronizing the rotation of said synchronizer mechanism and an adjacent gear at first and second times as said sleeve is moved into engagement with said adjacent gear.

12. The method of claim 11 , further comprising using an indexing mechanism for indexing said synchronizer sleeve into and out of engagement with said adjacent gears, said indexing mechanism including a plurality of retaining mechanisms disposed on the outer side of said hub and an equal number of detent portions disposed internally on said synchronizer sleeve and corresponding to said retaining mechanisms, each of said detent portions including means for locating said synchronizer sleeve laterally relative to said hub at a main synchronization position and at least one second synchronization position, each of said retaining mechanisms receivable at a main synchronization detent of said detent portions corresponding to said main synchronization positions and at a second synchronization detent of said detent portions corresponding to said second synchronization positions.

13. The method of claim 12 , further comprising engaging said plurality of gears using said intermediate clutch rings,

Assignees

• Perosky Edward
• Laba Lawrence
• Stiefel Christopher J
• Fca Us Llc

Inventors

• Perosky Edward
• Laba Lawrence
• Stiefel Christopher J

Classifications

• Y10T74/19284

  Meshing assisters · CPC title

• F16D23/06 Primary

  and a blocking mechanism preventing the engagement of the main clutch prior to synchronisation · CPC title

• F16D23/0612

  the blocking mechanism comprising a radial pin in an axial slot with at least one branch · CPC title

• F16D2023/0631

  Sliding sleeves; Details thereof · CPC title

• F16D2023/0618

  Details of blocking mechanism comprising a helical spring loaded element, e.g. ball · CPC title