From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Detailed description of a gear selection and locking mechanism, likely from a patent application.
| Identifier | ExFiles\Box 136\4\ scan0148 | |
| Date | 14th February 1933 guessed | |
| 1,897,851 3 has a wall 117. In this wall is an opening having located therein a ball 119 of a diameter substantially equal to the thickness of the wall. At the opposite end of rod 21' 5 are grooves 121 spaced to correspond with the axial positions of the rod for neutral, for second speed, and for high speed. To engage these grooves is a conventional spring detent indicated by numeral 103. In the 10 vicinity of ball 119' the rod 21' has openings 125 which are equally distant from the ball 119 when the parts are in their neutral positions. Within the openings 125 are spring-actuated plungers 127. Similarly 15 positioned in lock bar 79' are grooves 129, these grooves being spaced further apart than the openings 125. The difference in spacing is such that when the bar 79' is moved from its normal position one groove 20 129 will just register with a plunger 127 at the time that the clearance between the lever 47' and the arm 109 (or 111) has been taken up. Thereafter the lock bar and rod move together and the openings 125 and 129 25 will simultaneously move until they register with the ball opening. The spring-actuated plunger 127 will then push the ball 119 into the groove of the lock bar, the plunger 127 locking the rod 21' to the housing wall 30 117. From this position of locked engagement between the rod and the casing the rod may be moved only by a depression of the plunger 127 back into its opening 125. This is effected by the first movement of 35 the lock bar under the influence of the lever 47', this first movement causing the ball to be pressed into the housing wall opening by its engagement with the sloping wall of the groove in the lock bar. In so doing the 40 ball forces the plunger 127 down into the opening 125. When this has been accomplished the lever 47' has reached the one or the other of the arms 109 or 111. The shift may then be made as before to the 45 other position of adjustment. Figs. 9 and 10 show the positions of adjustment. Fig. 9 shows the parts in locked position for one driving ratio, and Fig. 10 shows the beginning of the return move-50 ment. It will be seen that the lock bar has been moved relatively to the rod and in doing so the ball has been pushed from the rod into the housing wall whereby the plunger has been pushed by the ball into the rod. 55 From the position shown by Fig. 10, further movement will effect complete registration of the groove in the lock bar and the plunger opening. When this complete registration has been effected the lock bar and recipro-60 cating rod move together until they jointly reach the position of the ball in the housing wall when the plunger again engages the casing and forces the ball into the lock bar. Figs. 11, 12, and 13 show still another 65 form which the invention may take. In this form the second and third speed fork 25'' is moved relatively to the fixed rod 21''. A spring-actuated ball 133 is located in the fork 25''. It serves to locate selected posi-70 tions of adjustment for neutral, second, and third speed by engaging notches 135 within the fixed rod 21''. The lever 29' engages between arms 134 on an upward extension of the fork 25''. It will be noted that the dis-75 tance between the arms 134 affords a clearance which must be taken up before the fork is moved. Slidable axially relative to the fork is a lock bar 137. This bar has a notch 139 dimensioned to snugly fit the lower end 80 of the lever 29' when moved transversely to engage the fork. It will therefore be seen that before taking up the clearance between the arms 134, the lever moves the lock bar. Within the fixed rod 21'' is a spring-actu-85 ated plunger 141. This plunger is intended to enter one or the other of two straight-sided notches 143 within the fork 25'' whereby the fork when in selected speed ratio positions may be locked to the rod. The lock 90 bar has two notches 145 with curved walls. These notches are spaced somewhat further apart than the notches of the fork. If the fork is in its neutral position and if the lever is midway between the arms 134, the 95 parts are substantially as shown in Fig. 12. If desired, there may be a further notch in the fork marked 146 on the drawings and there may be a shallow groove 148 in the lock bar, these parts serving to permit the 100 plunger 141 to act as a spring detent for the neutral position. If now the shift lever is moved, it first moves the lock bar to a position in which its notch is in full registration with a notch of the shift fork. The 105 two parts, the fork and the lock bar, there-after move together. When the movement is sufficient for the plunger to enter the registering notches of the fork and bar the engagement of the plunger with the notch in 110 the fork locks the latter to the fixed rod 21''. Thereafter the parts can be moved only by the movement of the shift lever. The angular faces of the notches of the lock bar associated with the free limited move-115 ment between the lock bar and the shift fork permit the plunger to be forced back into the rod 21'' at the beginning of the reverse movement of the lever. Upon a continuation of the movement of the lever the 120 parts may be moved to and locked in the other position of adjustment. Still another modification is shown by Figs. 14 and 15. This form shows a horizontally slidable rod 151 for shifting into 125 second and high speed. The shifts to second and to high are effected by moving in opposite directions from the neutral position which may be that shown in Fig. 15. The casing has a plurality of notches 153 to 130 engage a plunger 155 reciprocable in the | ||