Patent GB-803605-A (GB)
Title: Improvements in or relating to control apparatus for magnetic recorder-reproducer
Inventor: PASTOR SHELDON LEE
IPC: G11B15/10
Filed: 1956-10-15
Abstract: 803,605. Magnetic recording and reproducing apparatus. REVERE CAMERA CO. Oct. 15, 1956, No. 31309/56. Class 40 (2). The pressure roller 45 and capstan 43 of a magnetic recorder - reproducer, spring - biased apart, are manually brought into engagement, e.g. by rotation of a cam 66 in either direction from the neutral position shown to a " record " position (anticlockwise) or a " play-back " position (clockwise), and are so held by an automatic catch such as a member 97 spring-biased clockwise about a post 83 to cause a pawl 100 thereon to engage a shoulder 78 or 79 on the cam 66; the catch is manually released, e.g. by a plate 88 fixed at 89, 90 to the knob (not shown) used to control the cam 66 and having a sufficient lost-motion connection 73, 92 with the latter to enable its cam part 95 to force the pawl 100 clear of the shoulders 78, 79. The cam 66 shown is keyed to a shaft 65 coupled to the required electric switches (not shown), and is made of two plates spaced apart by short pillars, on two of which are mounted rollers 70, 71 which alternatively engage follower surfaces 112a, 113 on an arm 108 pivoted at 110 and having at its free end two overhanging plates 111 to hold it in alignment with the end 106 of a link 105 of a known reel-brake mechanism 60, 61 ; through a pin-and-slot connection and cushioning spring 46, the link 105 transmits the cam action to a lever 48 spring-loaded anti-clockwise at 47 about a pivot 49 and carrying the pressure roller 45 at its free end. A shoulder 75 may be provided on the cam 66 to prevent it from being turned to " record " except when a stop 76 is retracted by a push button 32. As applied to a machine having a known re-wind-neutralrapid-forward control slide 115, the mechanism includes a two-armed lever 117, 118 (having edges 130, 131 acted on by the slide 115) which is spring-biased clockwise about the post 83 and has a lost-motion connection 125, 126 with the member 97; when the slide 115 is moved from its neutral position, the anti-clockwise movement of the lever 117, 118 trips the catch-pawl 100 and also allows another two-armed lever 135, 140, spring-biased anticlockwise about the post 83, to rotate so that a recess 138 therein engages the part 89 and locks the plate 88 in its neutral position. The member 97 has an extension 99 engaged by a depending finger 102 on the " off-on-volume " knob 20, so that when the latter is switched off the catch-pawl 100 is always tripped, and the capstan and pressure roller are separated to avoid the formation of flat spots on the latter. The machine includes a motor 35 which by its roller 36, and through an idler 38, drives a flywheel 40 (carrying the capstan 43) coupled by a belt 51 to the take-up reel pulley 50; for rapid forward drive a roller 54 coupled directly to the take-up reel and frictionally to the pulley 50 is coupled to the flywheel 40 by an idler roller 53 cammed into contact. For re-wind, the lever mounting 56 of the supply reel is shifted to bring the roller 55 into contact with the motor roller 36.