Transmission with reverse gear brake

#The present disclosure relates generally to transmissions and more specifically to manual transmissions having an idler gear brake employed to reduce gear clash when shifting into a reverse gear ratio.

#The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art.

#A typical manual transmission includes a plurality of shafts, gears, shift mechanisms, synchronizers or other torque-transmitting mechanisms that cooperate to provide a plurality of forward and reverse gear or speed ratios. The transmission input shaft is selectively connected to an engine output shaft and includes a number of gears that are selectively connectable to the input shaft using, for example, synchronizers. The gears of the input shaft mesh with corresponding gears that are selectively connectable to an output shaft. To achieve a particular forward gear ratio between the transmission input and output shafts, the driver operates a shift mechanism, such as a manual shifter, that controls the engagement of the synchronizers with the desired gears. To achieve a reverse gear ratio, an idler gear is used to slide between an input shaft gear and an output shaft gear to reverse the rotational direction of the output shaft, and thus the drive wheels.

#The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

#FIG. 1 is a perspective view of a transmission according to the present disclosure;

#FIG. 2 is plan view of a shift fork and intermediate shaft assembly according to the present disclosure;

#The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.

#Referring to the drawings, wherein like reference numbers refer to like components, in FIG. 1 a perspective view of a partial transmission 10 of the present invention is illustrated. The transmission 10 includes an input shaft 12, a main shaft or output shaft 14 and an idler shaft 16 each supported by a housing 18. The input shaft 12 is connected to, for example, an engine output shaft (not shown) and the main shaft 14 is connected to, for example, a vehicle drive shaft (not shown) that provides torque to a drive wheel of the vehicle. The input and main shafts 12, 14 rotatably support a plurality of gears that intermesh to form a plurality of gear sets 15. A plurality of sleeves and synchronizers 17 is selectively manipulated to achieve a desired forward gear ratio between the input shaft 12 and the main shaft 14. For example, to achieve a forward gear ratio, one of the plurality of sleeves and synchronizers 17 is engaged to couple a gear from one of the gear sets 15 to one of the input shaft 12 and the main shaft 14 in order to transfer torque from the input shaft 12 to the main shaft 14.

#The idler shaft 16 is fixed securely with the housing 18 and supports an idler gear assembly 20. The idler gear assembly 20 is capable of selective movement along the idler shaft 16 to engage a reverse gear or member 22 of the input shaft 12 and a sleeve gear or member 24 on the main shaft 14. When a reverse gear ratio is desired, the idler gear assembly 20 meshes independently with the reverse gear 22 that is engaged with the input shaft 12 and the sleeve gear 24 that is engaged with the main shaft 14. The engaged idler gear assembly 20 reverses the direction of the sleeve gear 24 of the main shaft 14 and therefore reverses the direction of rotation of the drive shaft of the vehicle. For example, the idler gear assembly 20 is manipulated by a shift fork linkage 26 that includes a first end 26A secured to a reverse shaft or member 28 and a second end 26B that engages and moves the idler gear assembly 20 axially along the idler shaft 16. However, other methods or mechanisms of manipulating the idler gear assembly 20 may be employed without departing from the scope of the present invention.