Transmission gear selector arm and sleeves for shifting forks

In a transmission including a housing;

• an input shaft and an output shaft journalled in the housing;
• first, second, third and fifth forward speed gears journalled on the output shaft, a fourth forward speed gear fixed to the input shaft;
• first synchronizer clutch means connected to the output shaft having a reverse gear formed thereon for connecting selectively the first gear and the second gear to the output shaft;
• second synchronizer clutch means connected to the output shaft for connecting selectively the third and the fourth gears to the output shaft;
• third synchronizer clutch means connected to the output shaft for selectively connecting the fifth gear to the output shaft;
• a cluster gear assembly having gear elements respectively engaged with the first, second, third, fourth and fifth speed gears;
• a reverse drive idler journalled for rotation about an axis parallel to the axis of the output shaft, engageable with a reverse gear element of the cluster gear assembly and the reverse gear of the first synchronizer clutch means, the gear shift and interlock mechanism comprising;
• a shift rail mounted for axial movement and rotation having first and second selector pins fixedly secured thereto and extending therefrom;
• a first shift fork slideably mounted on said shift rail, engageable with the first synchronizer clutch means and the first selector pin and adapted to be moved axially by the pin;
• a second shift fork slideably mounted on said shift rail, engageable with the second synchronizer clutch means and the first selector pin and adapted to be moved axially by the pin;
• a pivotably mounted reverse drive lever having a first end engageable by the first selector pin and a second end adapted to move the reverse idler into engagement with the reverse drive element of the cluster gear assembly and with the reverse gear of the first synchronizer clutch means;
• a third shift fork mounted on the shift rail, engageable with said third synchronizer clutch means, adapted to be engaged by the second selector pin and to be moved axially thereby;
• first interlock means fixed against axial movement and mounted for blocking axial movement of said first and second shift forks and rotation of said reverse drive lever when said second selector pin engages said third shift fork, for selectively blocking such axial movement and rotation when said first selector pin engages either of said first or second shift forks or said reverse drive lever, but selectively permitting the axial movement of either the first or second shift fork or rotation of the reverse drive lever when said first selector pin is engaged therewith, whereby the first, second, third or fourth gears and the reverse gear are connected to said output shaft when the shift rail is moved;
• second interlock means fixed against axial movement and mounted for blocking axial movement of said third shift fork when said first selector pin engages said first or second shift forks or said reverse drive lever, but permitting axial movement of said third shift fork when said second selector pin engages said third shift fork, whereby said fifth speed gear is connected to said output shaft by said third synchronizer clutch means when said shift rail is moved.