Synchronizer in electro-mechanical transmission

1. An electro-mechanical transmission including an input member, an output member and a plurality of planetary gears and torque transfer devices, the electro-mechanical transmission further comprising:

a synchronizer selectively engaging and disengaging input and output components of the transmission, the synchronizer comprising

a piston sequentially applying a synchronizing force and a clutching force when said synchronizer is activated,

a blocker member,

an input cone associated with said input components and extending radially inside said blocker member,

an output cone associated with said output components and extending radially inside said blocker member and having a radius different than said input cone,

a sleeve member coupled to said piston member and compressing said blocker member thereby generating a friction force between said input and output cones to synchronize rotational speeds between the input and output components in response to said synchronizing force and, after the rotational speeds between the input and output components are synchronized to establish a clutch slip of zero between the input and output components, sequentially engaging said output components to said input components in response to said clutching force, and

a biasing member providing a biasing force against said piston and sleeve member in a direction opposite to said synchronizing and clutching forces, thereby disengaging said output components from said input components when said synchronizer is deactivated.

2. The electro-mechanical transmission of claim 1 , wherein said piston member, sleeve member and biasing member are associated with said output components.

3. The electro-mechanical transmission of claim 1 , wherein said input components rotate independently of said output components.

4. The electro-mechanical transmission of claim 3 , wherein said output components correspond to a stationary transmission housing and said input components correspond to gear members associated with one of the planetary gears.

5. The electro-mechanical transmission of claim 1 , wherein said output components correspond to a first set of gear members associated with one of the plurality of planetary gears and said input components correspond to a second set of gear members associated with one of the plurality of planetary gear sets.

6. The electro-mechanical transmission of claim 1 , further comprising a control module monitoring the rotational speeds of said input and output components and selectively activating and deactivating said synchronizer when monitored rotational speeds are synchronized.

7. A two-mode compound split hybrid electro-mechanical transmission, comprising:

a plurality of transmission components;

a synchronizer selectively engaging and disengaging at least two of the transmission components to effect operation in a speed range in the transmission, the synchronizer further comprising:

a plurality of input components associated with one of said transmission components;

a plurality of output components including a clutching mechanism engaged to one of said input components when said synchronizer is activated and disengaged from said input component when said synchronizer is deactivated; and

the clutching mechanism including a piston applying a synchronizing force for synchronizing rotational speeds between the input and output components and, after the rotational speeds between the input and output components are synchronized to establish a clutch slip of zero between the input and output components, sequentially applying a clutching force by said piston to engage said output components to said input components.

8. The electro-mechanical transmission of claim 7 , wherein said input components rotate together independent of said output components.

9. The electro-mechanical transmission of claim 7 , wherein said output components rotate together independent of said input components.

10. The electro-mechanical transmission of claim 7 , wherein said output components are stationary and said input components rotate.

11. The electro-mechanical transmission of claim 7 , wherein said input components are stationary and said output components rotate.

12. The electro-mechanical transmission of claim 7 , wherein one of said transmission components includes a transmission housing.

13. The electro-mechanical transmission of claim 7 , wherein at least one of said transmission components includes a planetary gear set utilizing first, second and third gear members.

14. The electro-mechanical transmission of claim 7 , wherein said input and output components include input and output synchronization cones for synchronizing rotational speeds of said input and output components when said synchronizer is activated.

15. The electro-mechanical transmission of claim 14 , wherein said output components further include a piston coupled to a sleeve member, said piston applies a synchronization force to translate said sleeve member and compresses said output synchronization cone to generate friction between said input and output synchronization cones.

16. The electro-mechanical transmission of claim 14 , wherein said input and output components require rotational speeds within the same vicinity of one another prior to synchronization and activation of said synchronizer.

17. The electro-mechanical transmission of claim 16 , wherein said vicinity is less than or equal to 50 RPM.

18. The electro-mechanical transmission of claim 7 , wherein the rotational speeds of said input and output components must be synchronized to a difference in rotational speeds of substantially zero prior to engagement.

19. The electro-mechanical transmission of claim 7 , wherein said clutching mechanism engaging to one of said input components when said synchronizer is activated and disengaging from said input component when said synchronizer is deactivated comprises:

a piston applying a clutching force when said synchronizer is activated;

a sleeve member coupled to said piston member and selectively engaging to one of said input components in response to said clutching force; and

a biasing member selectively disengaging said sleeve member from said input component when said synchronizer is deactivated.

20. Method to selectively engage and disengage rotation of input and output components within a transmission utilizing a synchronizer, the method comprising:

monitoring rotational speeds of said input and output components;

applying a synchronization force for synchronizing the rotational speeds of said input and output components when said synchronizer is activated based on the monitored rotational speeds;

applying a clutching force to engage said input and output components after the rotational speeds of said input and output components are synchronized to establish a clutch slip of zero between the input and output components when said synchronizer is activated;

monitoring torque transferred between said engaged input and output components; and

utilizing a biasing force to disengage said output members from said input members based on said monitored torque.

21. The method of claim 20 , wherein said synchronizer is deactivated when said torque transferred between said input and output members is substantially zero.