Patent GB-637465-A (GB)
Title: Coin controlled locking device for typewriters
IPC: G07F17/26
Filed: 1947-07-29
Abstract: 637,465. Coin-freed typewriters. FORD, M. C. July 29, 1947, No. 20456. Convention date, July 30, 1943. [Class 27] Coin-freed mechanism, embodied in a unit which can be applied to a typewriter for controlling its use, has an element connected to the typewriter carriage which it holds against movement until freed by an inserted coin, whereupon the reciprocations of the carriage as the typewriter is used are communicated to the element and ultimately cause its relocking when the carriage has made a predetermined number of reciprocations allowed for the coin. The mechanism shown is enclosed in a casing 1 secured to the rear of the typewriter and the element connected to the carriage is a reciprocable rack bar 4 meshing with a gear 44 which is normally locked by a pivoted spring-loaded pawl 40, a roller 39 on the pawl then resting in a recess 38 in a rotatable disc 36. An inserted coin frees a hand operated lever 26 which, when depressed, lowers a rack 29 to turn a pinion 31 clockwise (Fig. 1) so that a pin 33 on the pinion comes up to a stop 34 on a ratchet wheel 35 fast with the disc 36 and then carries forwardly the ratchet and disc a small amount. The handle returns under spring action when released, carrying with it the rack 29 and pinion 31, but the ratchet 35 and disc 36 remain displaced, the disc 36 disengaging the pawl 40 from the gear 44 so freeing the carriage of the typewriter. Whilst the typewriter is being operated the reciprocations of the carriage are communicated by the rack 4 to the gear 44 and thence, through a pawl 51 and ratchet 52, to an eccentric 53 which oscillates a pawl 54 engaging the ratchet wheel 35. In this way the initial displacement of the ratchet 35 and disc 36 is continued step-wise by the carriage movement until finally, when a predetermined number of lines or amount of matter have been typed, the ratchet and disc complete a revolution, the roller 39 drops back into the recess on the disc and the pawl 40 relocks the gear 44 to render the typewriter again inoperative. Coin action, mechanical-connection.- Full and effective downward movement of the hand lever 26 is normally prevented by a pawl 21, Fig. 3, pivoted to a lever 12 which is pivoted at 13 and urged towards a coin channel 8 by a spring 14. An inserted coin passes down the channel and lodges on a slope 18 on the lever 12. During its initial free downward movement the hand lever 26 bears down on the coin, so thrusting the lever 12 side-ways to carry the pawl 21 clear to permit a full movement of the lever, at the completion of which the coin is discharged into the till 3. The pawl 21 rocks on its pivot to clear the hand lever 26 on its return movement but, if a full forward movement has not been made, the coin remains in the channel 8 and holds the lever 12 in a position in which an off-set part 16 obstructs the full return of the hand lever. A pawl 46, Fig. 1, then locks the gear 44 to prevent use of the typewriter to compel the user to repeat actuation of the hand lever and so ensure correct displacement of the disc 36. The hand lever 26, when fully returned, rocks the pawl 46 clear of the gear 44.