918,001. Permutation locks. SIMPLEX LOCK CORPORATION. May 26, 1961, No. 19111/61. Class 44. A permutation lock comprises a number of individually rotatable code gear assemblies, each of which has an opening 37 and its own operating means by which it can be rotated so that it moves into connection with teeth on and rotates with, a counter gear shaft, subsequent rotation of other code gear assemblies after the first by their corresponding operating means bringing them successively into connection with the teeth on and rotating them with the counter gear shaft so that the code gear assemblies which have previously been brought into connection with the counter gear shaft are also rotated, the lock also comprising a slide 61 which has parts 62 that are adjacent to the code gear assemblies and that can enter the openings 37 so that the slide can move to an unlocking position when the openings have been moved to predetermined positions as a result of the rotation of the code gear assemblies by the operating means according to a predetermined sequence. As shown in Figs. 7 and 10, the operating means for each code gear assembly consists of a spring- loaded plunger 27, a pivoted member 51 and an idler assembly; each of the code gear assemblies consists of a gear-wheel 35, having teeth around the whole of its periphery, and a disc 36, the gear 35 and disc 36 being fixed together and the opening 37 being a notch in the periphery of the disc. Five code gear assemblies are used in the lock and they are freely rotatable on a shaft 32 but are prevented from axial movement along the shaft. Each idler assembly consists of a gear 38, having teeth around a part of its periphery only, and two discs 39, 40 which are fixed together and to the gear 38, the gear 38 meshes with the gear 35 of its corresponding code gear assembly; the disc 39 has a notch 41 in its periphery and this is engaged by a prong 56<SP>1</SP> on the pivoted member 51 so that when the plunger 27 is depressed to pivot the member 51 the prong 56<SP>1</SP> rotates the idler assembly and hence the code gear assembly. The disc 40 has a recess 42 extending over a portion of its periphery and when the plunger 27 is depressed a portion 50 of the plunger moves into the recess and by engagement with an end wall of the recess limits the rotation of the idler assembly to a predetermined amount. The idler assemblies are freely rotatable on a shaft 33 but cannot move axially on the shaft. Each gear 43 on the counter gear shaft has teeth over only a portion of its periphery and is so mounted in relation to its idler assembly that movement of the idler assembly through a distance of one tooth takes place before the first tooth of the idler assembly engages a tooth of the counter gear 43; the depression of each plunger 27 moves the corresponding idler assembly and hence the code gear assembly a distance of two teeth and hence the corresponding counter gear is only rotated a distance of one tooth since depression of each plunger 27 rotates its counter gear a distance of one tooth and all the gears are rigidly connected together by means of a shaft 34. The operation of each plunger after the first not only moves its associated code gear assembly a distance of two teeth but also moves the previously rotated code gear assembly or assemblies a distance of one tooth through the counter gears and idler assembly or assemblies. When all the plungers in the sequence have been depressed in a predetermined order the openings 37 in the code gears assemblies are aligned. The code assemblies are held in the aligned position by a spring-loaded pawl which bears on the teeth of one of the counter gears. When the openings 37 are aligned a shaft 29 which can be rotated by a knob 30 is freed for rotation in a clockwise direction since the slide 61 which normally prevents its rotation can move into the openings 37. The shaft 29 is connected to for example, a combined ignition and starter switch of a motor vehicle which is controlled by the lock; the shaft 29 carries a cam 75, Figs. 11 and 13, which has three projections 76, 77, 78, the projection 78 normally engaging the slide 61 and preventing rotation of the shaft 29 in the clockwise direction until the openings 37 are aligned. The shaft 29 also carries a disc 74 which has a notch 90 in its periphery which is rotatable on the shaft 29; a pin 79 on the cam 75 projects into the notch 90 and thus provides a lost-motion connection between the cam and the disc. The outside diameter of the disc is greater than the protrusion of the projection 78 and the arrangement is such that rotation of the shaft 29 first moves the slide 61 into the openings 37 of the code gear assemblies by the engagement of the projection 78 with the slide and further rotation results in the edge of the disc 74 moving underneath the slide and lifting it above the projection 78; since the slide is biased to the left by a spring 67 it then moves to the left out of the openings 37. Further clockwise rotation of the shaft 29 causes the projection 76 of the cam 75 to engage a surface 80 on the shaft 34 which carries the counter gears and the clockwise movement of the shaft 29 turns the shaft 34 and returns the counter gears to their initial positions. The idler assemblies are turned towards their initial positions by the rotation of the counter gears 43 and when their teeth have cleared the counter gears, springs 55 which bias the members 51 complete the return of the idler assemblies to their initial positions through their engagement with the discs 39; the movement of the idler assemblies moves the code gear assemblies back to their initial positions. The shaft 29 can be turned still further clockwise beyond the position in which the slide 61 is released, to operate, for example, switch contacts controlling the starting motor of the motor vehicle. Such further movement of the shaft 29 biases a spring 72 by engagement of an arm 70 connected to the shaft with a leg 71 of the spring so that immediately the shaft is released it returns to the position taken up before said further rotation. To lock the shaft 29 again against clockwise rotation it must be manually moved anti-clockwise beyond its locking position, this being necessitated by the lost-motion connection of the shaft with the disc 74 through the pin-and-notch connection. When the periphery of the disc 74 moves clear of the slide 61 the slide drops back to its locking position and release of the shaft 29 re-engages the projection 78 with the slide 61. The shaft 29 is biased to the locked position by the spring 72 since when it is rotated anti-clockwise beyond the locked position the spring 72 is tensioned by engagement of a second leg 71 with an arm 73 connected to the shaft 29. To change the permutation the plungers 27 are depressed in the existing sequence to bring the openings 37 of the code disc assemblies into alignment and the shaft 32 carrying the code disc assemblies is then moved to the left so that the parts 62 of the slide 61 enter the openings 37 to prevent rotation of the code disc assemblies and to disengage the gear-wheels 37 of the code disc assemblies from the gears 38 of the idler assemblies. The shaft 32 is retained either in its normal position or in the position to which it has been moved by a spring 84 which engages a cam 82, Fig. 14, on the shaft. The shaft is moved to the left by pressing on the end 88 of a slide 44 the end 88 engaging an enlarged end 89 of the shaft 32. Pressing on the end 88 of the slide also moves the slide 44 to the left, causing the slide to engage in a recess of a cam 68 fixed to the control shaft 29 to prevent rotation of the control shaft clockwise; the shaft 29 is then turned anti-clockwise and the projection 77 of the cam 75 engages the follower surface 80 on the shaft 34 and so causes rotation of the shaft 34 to move the counter gears 43 back to their initial positions and to allow the idler assemblies to return to their initial positions. The slide 44 is also returned to its initial position by a projection (not shown) on the cam 68 so that the portion 88 is clear of the enlargement 89 of the shaft 32. The plungers 27 are then operated according to a chosen sequence to give a new permutation, rotating the idler assemblies and counter gears 43 as described above. The shaft 29 is then turned clockwise beyond the locking position to move the slide to the right, since the parts 62 of the slide 61 are already engaged with the code gear assemblies, they and their shaft 32 are also moved to the right to their normal positions so that the gear-wheels 35 engage the idler gears 38 again. The new permutation is then set up and the shaft 29 can be locked by turning it further clockwise to allow the disc 74 to lift the slide 61 so that the slide moves back to its initial position and so that the cam 75 rotates the counter gears and idler assemblies and hence the code gear assemblies to their locking positions as described above. When this has been done, the shaft 29 is rotated anti-clockwise beyond its locking position and then released as described above, so that it is moved by the spring 72 to the locked position. In a modification, Fig. 18 (not shown), instead of the idler assemblies being mounted on a separate shaft they are on the same shaft as the code gear assemblies and instead of each code gear assembly having a gear-wheel which engages with the gear of the idler assembly a dog clutch is provided; this consists of a gear-like member on the idler assembly engaging an internal gear-like part of the code gear assembly so that the code gear assembly can take up a number of positions relative to the idler assembly depending upon the number of teeth. Instead of the code gear assemblies being moved by moving their shaft they are moved by a slide having a projection for each assembly which engages an annular groove in the assembly. The other details are sim