| 摘要 |
<p>1294827 Vehicle-transmission parking brakes; positive detents; transmitting mechanism FORD MOTOR CO Ltd 25 May 1971 [1 July 1970] 16830/71 Heading F2E A parking gear 28 is secured to the output shaft 12, Figs. 2B and 7A, of an automatic transmission 10, 20, and engageable with it is a pawl 116, which is actuated for that purpose by a cam 36 on a cam rod 32 which, in turn, is moved approximately longitudinally by pivoting of a lever 40, Figs. 2A and 3, about the axis of shaft 52. The invention is concerned, inter alia, with the arrangement and location of the lost motion mechanism needed to provide for the situation where the pawl tooth 120 is not aligned with a space 122 on brake application. Lever 40 is secured to shaft 52 for rotation by a manually-operated drive-selection lever 72 into a number of discrete positions governed by teeth 88 on the lever 40 and a spring-urged roller 90. The position of lever 40 shown in full lines in Fig. 2A corresponds to "brake on". End 100 of rod 32 is bent at right angles and resiliently retained in a slot 98 of an arm 96 of the lever by a torsion spring 84 which at one end 82 urges the lever counterclockwise and at the other end 110 engages a bracket 102 pivoted on the rod end 100. In operation, assuming pawl tooth 120 is opposite a gear tooth 30 when lever 72 is moved to "brake on" position, the cam 36 (and hence rod 32) will be checked before reaching its most extreme rightward position by engagement of cam 36 with pawl 116 in an outer position and with a fixed block 112. Rod end 100 will therefore hold spring end 110 by means of bracket 102, while lever 40 continues to rotate, storing energy in spring 84 by moving its end 82, and moving the end of its slot 98 away from rod end 100; lever 40 finally comes to rest with roller 90 in the last notch. Parking gear 28 is now rotated slightly to align a space with pawl tooth 120, whereupon spring 84 urges rod 32 to the right, causing cam 36 to drive pawl 116 clockwise (Figs. 2B and 7A position), until rod end 100 reaches the closed end of slot 98 once more (Fig. 2A position).</p> |
