Patent GB-691762-A (GB)
Title: Escapement mechanism for controlling relative movement between projected character images and a light-sensitized surface in a photographic type-composing machine
IPC: B41B21/36
Filed: 1949-11-16
Abstract: 691,762. Photographic type - composing. HIGONNET, R. A. E., and MOYROUD, L. M. Nov. 16, 1949 [Nov. 24, 1948], No. 736/51. Divided out of 691,738. Class 98 (i). A photographic type-composing machine includes a film carriage which is displaced intermittently by the width of the character projected by means of a variable escapement, which escapement comprises a gear-wheel 37, Fig. 3, mounted coaxially with a toothed sector 39 provided with stop arms, the gear-wheel and sector both meshing with a pinion 40, and wherein (1) wheel 37 is locked by a pawl of a lever 47, and the pinion 40 is moved out of mesh with the wheel and the sector so that the sector 39 rotates under spring-action in the direction opposite to the normal direction of rotation of the wheel 37 until one of its stop-arms meets a member, being one of a number of members each of which, on operation, effecting different movement of gear-wheel 37; and (2) wheel 37 is freed by the pawl of lever 47 and pinion 40 meshes again with the wheel 37 and sector 39, so that the wheel and the sector are driven together by an outside source of power until one arm 57 of the sector reaches its fixed rest abutment 64. A number of members such as 41 are operated electromagnetically by the character selection mechanism of the machine, that member being operated to project into the path of one of the arms of sector 39 which will allow the sector to move, when freed, a distance corresponding to the width of the character selected. Immediately thereafter an electro-. magnet 42 is energized, drawing a rod 43 to the left. A shoulder 45 on the rod 43, and a spring 49 move lever 47 to bring its pawl into engagement with gear-wheel 37, which is thereby locked; and a shoulder 50 on the rod rocks a lever 51 carrying pinion 40, which is moved out of mesh with the wheel and the sector and is engaged by a stop-member 53. Sector 39 moves under spring action until one of its arms meets the member such as 41 which has been operated, a spring-pressed pawl 54 riding over the teeth of the wheel 37 and preventing any return movement of the sector. Magnet 42 is then de-energized, and rod 43 moves to the right under action of its return-spring 61. The shoulder 50 rocks lever 51, bringing pinion 40 into mesh with gear-wheel 37 and sector 39, and a shoulder 44 on the rod rocks lever 47, freeing gear-wheel 37. Wheel 37 then turns under spring action until arm 57 reaches stop 64. Wheel 37 meshes with a gear 19, Fig. 1, meshing with a gear 20 on a shaft 29 fast with a screw 17 which advances the film carriage, against action of a return spring on the carriage and of a spring acting on shaft 29 through a wire 25. Shaft 29 is held in in conical bearings 21, 22. Bearing 21 is mounted in the frame of the machine, while bearing 22 is mounted in a slidable cup 26 so that it may yield slightly against action of a spring 27 when the carriage stops suddenly. At the end of a line, an electromagnet DEB is excited, drawing the shaft 32 of gear 19 to the left to disengage gears 19, 37. The carriage then returns by action of its return springs. Shaft 32 is returned by spring 31 abutting an adjustable stop-piece 35. Specifications 669,531, 691,738 and 691,763 are referred to.