GB1111111A - Improvements in or relating to mechanisms for coating surfaces with liquid - Google Patents

Abstract

1,111,111. Coating apparatus. PURDY MACHINERY CO. Ltd. 24 July, 1964 [2 Aug., 1963], No. 30818/63. Heading B2L. [Also in Division H2] Mechanism for coating a travelling surface with liquid includes a transfer roller for transferring the liquid to the surface, means including a pump for delivering the liquid to the roller and coating the roller surface with the liquid, and driving means for the roller and pump comprising two inputs, each including a unidirectional clutch, the first arranged to drive the roller and pump when the second is idle and the second arranged to drive the roller and pump when the first is idle. The machine shown in Fig. 1 includes a drum 1 which rotates uniformly during operation of the machine, picker mechanism (not shown) which takes labels from magazines 2, 3 and applies them to drum 1 where they are held by suction and carried past mechanism M which applies adhesive to the exposed surfaces of the labels. The labels are then applied to bottles carried along by an endless conveyor 4 and a scroll 5 at position B. The adhesive applying apparatus M (Fig. 3) consists of a sump 6 from which the adhesive is pumped by helix 18 via tube 20 and discharged adjacent the top of carrier roller 10. A spreader roller 11 (behind roller 10 and not visible in Fig. 3) spreads the adhesive evenly over the surface of roller 10 such that an even layer of adhesive is transferred from roller 10 to transfer roller 12 which is in sections 12a, 12b and 12c arranged to contact labels at various heights on the drum 1. Fingers 26 fixed on rod 27 project into grooves 28 in roller 12 to avoid the labels being drawn away from the drum I by roller 12. The spreader roller 11 (not shown) is adjustable relatively to roller 10 so as to provide the required adhesive layer thickness and the roller 12 is movable round the periphery of roller 10 so that it can be moved out of contact with the drum 1 when there is any absence of labels thereon. This can be done automatically by sensing means operating a solenoid device for moving roller 12. In order that the mechanism M can be operated before the machine starts to apply labels so that the adhesive roller 10 is properly wetted before the first labels arrive to receive the adhesive, the mechanism shown in Fig. 6 is provided. This comprises a gear box having two input shafts 79, 80, 79 being connected to the main driving motor of the machine and 80 being connected to an auxiliary motor. The arrangement is such that the respective drives are through unidirectional clutches 93 and 81 such that which-ever drive has the higher speed this drive drives the respective output shafts 86 to the adhesive pump, 91 to the roller 10 and 96 through flexible couplings 94, 95 to roller 12. On starting up, the auxiliary drive 80 only is operated, the main drive motor being stationary so that there is a period for the rollers to be properly wetted with the coating liquid before the machine starts operating. When the main motor is started shaft 79 begins to rotate at a higher speed than shaft 80 so that the shaft 79 takes over the drive of the gear train. The auxiliary motor may then be stopped. The auxiliary motor is preferably a two-speed motor so that it can be run at a higher speed and this can be used for pumping water through the apparatus for cleansing purposes.