Patent GB-845289-A (GB)
Title: Multi speed, lever controlled transmission
IPC: F16H59/04
Filed: 1956-11-01
Abstract: 845,289. Change-speed control. FULLER MANUFACTURING CO. Nov. 1, 1956 [Dec. 25, 1955], No. 33361/56. Class 80 (2). Gearing for motor vehicles in which different ratios are selected by axial movement of selector rods &c. has the selector rods arranged in at least two groups and the shift lever restricted to operation of the rod or rods in one group only at a time. In one form, a gear shift lever 22, Figs. 3, 6, 10, carries pivotally at 109 a depending selecting finger 100 which is biased by a snap-over spring mechanism under the control of a catch lever 118 to engage either with forked members 98, 99 secured to selector rods 92, 93 comprising a first group, or with forked members 96, 97 fast on selector rods 90, 91 forming a second group. The selector rods 92, 93 are slidden axially to engage reverse and the first three ratios in a change-speed gear, and the selector rods 90, 91 are slidden axially to establish a further four forward ratios in the change-speed gear. The snap-over mechanism consists of a first lever 110, pivoted at 114 on the gear shift lever 22 under the control of the catch lever 118, engaging with its under-side the top 117 of a second lever 116 pivoted at 119 to the gear shift lever and carrying pivotally at its ends two telescopic spring struts 125 having heads at their inner ends engaging recesses 130 on each side of the depending selector finger 100. In changing up through the ratios, the operator first engages first, second and third speeds in sequence. To change from third to fourth ratio, the catch lever 118 is operated to turn the levers 110, 116 about their pivot axes to the position shown in Fig. 3. Since, however, when the third ratio is engaged, the fork 98 on the selector rod 92 is out of alignment with the forks 99, 96, 97 on the other three selector rods, this operation serves only to prestress the telescopic struts 125, and does not effect movement of the selector finger 100. The operator then moves the shift lever 22 to the neutral position, so that the stressed telescopic struts can then slide the selector finger 100 across to the position shown in Fig. 10. The operator then engages the remaining ratios by performing the same shift pattern of the lever 22 as was employed to establish the reverse and three forward ratios controlled by the selector rods 92, 93. In a modification, the shift lever 22, Figs. 7, 8, 13, is provided with two depending selector fingers 150, 150a pivoted at 144. The selector fingers are alternatively locked to the shift-lever 22 by a catch 145, biased to turn one way or the other of Fig. 13 to engage recesses 149 in the selector fingers by springs 155, 156. The catch lever 118 and the shift-lever 22 is connected to a pair of bell-crank levers 160, 160a mounted on opposite sides of the shift lever and engaging the ends of the two springs 155, 156 which are stressed to bias the catch 145 in opposite directions. Operation of the catch lever 118 turns the bell-crank levers 160 to increase the stress of one spring 155, 156 and decrease the stress of the other, thereby effecting turning of the catch 145 about its pivot to lock one selector finger 150 to the shift-lever 22. The selector finger 150 is engaged with one or other of the forks 96, 97 fast with the selector rods 90, 91 and the selector finger 150a is engaged with one or other of the forks 98, 99 fast with the selector rods 92, 93. Operation of the shift lever 22 through the same shift pattern accordingly slides either the rods 92, 93 or the rods 90, 91, depending upon which selector finger is locked by the catch 145. The shift lever 22 controls a changespeed gear comprising a driving shaft 15, Fig. 1, fast with a gear 31, an intermediate shaft 14 carrying gears 32, 35, 44, 46 selectively positively clutched thereto and a gear 49 carried axially slidable upon splines 48, a countershaft 70 carrying fast gears 72, 74, 75, 76, 77, 80, 81, and a reverse train comprising a double gear 56 slidden leftwards to engage a gear 82 fast on the end of the countershaft 70 for the lowest forward ratio and rightwards to engage a reversing idler 87. Conventional interlock means 88 are provided between the selector rods 90 &c. to prevent more than one ratio being engaged at the same time.