| 摘要 |
1,179,541. Change-speed control. D. A. THOMAS. 14 Aug., 1968 [21 Aug., 1967], No. 38881/68. Heading F2D. Manual gear shift mechanism for changing ratio by straight forward and backward movements of a gear lever comprises a manual gear lever 34 pivoted at 35 and engaging an opening 36 in a member 22 which has apertures 21, 23 at its ends receiving vertical extensions of actuating members 13, 14 which shift the gears. The actuating members 13, 14 are alternatively lockable in their neutral positions so that forward or backward movement of the gear lever 34 pivots the member 22 about the extension of the locked actuating member 13 or 14 and shifts the other actuating member to a gear establishing position. The actuating member 14 is locked by its vertical extension 19 engaging an aperture 38 of a housing wall 29, the extension being raised out of the aperture to release the actuating member 14 by a plunger 48 on a lever 41 which is pivoted to the wall 29 and raised against spring bias by raising an operating member 44 which is slidably mounted on the gear lever and connected to the lever 41 by a cable 43. The actuating member 13 is locked by a lever 53 engaging a notch 54 provided in the actuating member, the lever 53 being pivoted at an intermediate point to a bracket depending from the housing and having its other end co-operating with the actuating member 14 so that when the actuating member 14 is locked the lever 53 disengages the notch 54 to release the actuating member 13, but when the actuating member 14 is raised to release it the lever 53 engages the notch and locks the member 13 in its neutral position. For a four speed gear, first gear is obtained by raising the operating member 44 to release the actuating member 14 and then pivoting the gear lever 34 forwardly so that the actuating member 14 moves rearwardly (to the right in Fig. 3) its extension 19 riding on a plate 49 secured to the wall 29. For second gear the lever 34 is shifted rearwardly and the actuating member 14 is thus moved forwardly to its second gear position. For third gear the lever 34 is shifted forwardly, at the midpoint of its movement the extension 19 strikes the edge of the plate 49 and drops into the aperture 38 so that the lever 53 is pivoted and releases the actuator member 13, whereafter further movement of the gear lever pivots the member 22 about the extension 19 and the actuating member 13 is shifted rearwardly to the third gear position. For fourth gear the gear lever is shifted rearwardly thus shifting the actuating member 13 forwardly to the fourth gear position. Reverse is obtained with the aid of a second gear lever. The shift mechanism is also adapted for use with a three speed transmission wherein reverse is obtained in the position corresponding to first gear for the four speed transmission. |
