GB1178313A - Drive System for Film Processing Apparatus. - Google Patents

Abstract

1,178,313. Handling thin material. PHOTOMEC (LONDON) Ltd. 28 June, 1968 [21 July, 1967], No. 33722/67. Heading B8R. [Also in Division G2] In a roller system for transporting a continuous strip of film through a processing apparatus, the drive rollers 20 are driven by being drawn, against biasing means, into contact with a drive shaft 22, and the rate of advance of the film by the rollers is higher than the rate at which the film traction system is drawing the film on. As shown in Fig. 1, the film 9 passes from a supply spool 10 over an elevator system 12, 13, and then through a section 15 comprising one or more processing tanks, to a drying section 16, then between drive rollers 17, 18 and over another elevator system 19 to a take-up spool 11. In the tank section the film passes over several sets of rollers 20 and lower rollers 21. Each of the upper rollers 20 is mounted separately on a pivot 24 at one end of a lever 25 swingably mounted on a spindle 26 common to each set of upper rollers. The upper rollers are urged upwards by springs 28. Below each set of upper rollers is a drive shaft 22, all these drive shafts being coupled together by belts 31, and driven via a belt 34 and spindle 33 from a motor 32. The rollers 20 are normally biased by springs 28 so that they are out of contact with drive shafts 22, but can be drawn into contact with them when the tension in the film increases sufficiently. The same motor 32 serves to drive roller 17 via a gear-box 44, the speed being adjustable by a knob 45. The speed at which the film is drawn through the apparatus by drive roller 17 is less than the speed at which the film is advanced when rollers 20 are drawn into contact with drive shafts 22. Thus an increase in the film tension, causing rollers 20 to contact shafts 22, is rapidly relieved, and fed back to the elevator at the feed-in side.