Patent GB-538968-A (GB)
Title: Improvements relating to machines for coating containers with paraffin wax and the like
IPC: B31B1/74
Filed: 1940-03-06
Abstract: 538,968. Coating containers. AMERICAN CAN CO. March 6, 1940, No. 4223. Convention date, March 17, 1939. [Class 95] A machine for coating containers with paraffin wax or the like, of the kind comprising in combination a reservoir for the molten wax, a coating conveyer in said reservoir for carrying containers down into and through said wax with their longitudinal axis extending transversely of the direction of movement, a chilling chamber adjacent said reservoir, a chilling conveyer in said chamber for carrying coated containers therethrough, means for transferring the coated containers to said chilling conveyer and means for draining excess paraffin wax from the containers, is characterized in that said draining means comprises means for rocking each container about an axis extending in the direction of movement of the container. Directly beneath the container magazine A is the container feeding device B which comprises a rotatable double disc turret 31 carrying cam-operated container saddles or carriers 35. The closure element b of the container a is held open, as the turret 31 rotates, by a member 48, and, on reaching the bottom of the feed turret 31, the containers are transferred into a rotatable auxiliary feed turret 51, provided with spaced angular pockets 52, and thence, by means of the guide bars 131 into the coating conveyer C. The two turrets 31 and 51 are driven in unison. The coating conveyer C comprises a plurality of double-conical holders or buckets 101, and its rollers 105 ride in grooved tracks 111 and engage between the teeth of sprockets 108, 109. The lower inclined run of the conveyer C extends down into a steam-jacketed wax containing tank D, and the containers are entirely submerged in the molten wax, which also enters the containers through their dispensing holes c. On leaving the guide bars 131, 133, the containers contact a curved guide plate 135, and are thereby rotated through 180 degrees so that the wax is spread completely over the inside and outside thereof. The containers are then engaged by upper guide bars 141, 142, the entrance ends of which have a quarter turn twist, and by this means the containers are swung into inverted position so that they are emptied and drained of excess wax. After traversing a half-turn runway section, the containers, now in upright position are discharged from the coating conveyer C, by a horizontal rotatable transfer turret 151, being held against displacement by cam-operated pivoted fingers 181. The transfer turret 151 conveys the containers to the chilling conveyer E, disposed in a chilling chamber F, located adjacent to the wax tank D. This conveyer E comprises a chain 192 provided with container cages 201 and holding-prongs 202, 203, and guides 208, 211 and 212 are provided. Air, from the blower 241, passes through a filtering and cooling device 231 and is continuously circulated through the chamber F, and, as the containers pass around the sprocket 194, they are charged with filtered air by a charging device G comprising spaced air-charging heads 256, the filling tubes 257 of which enter the containers through their filling openings c. On removal of the filling tubes 257, the closure elements b of the containers are closed by the belt 275 and are sealed by the wax which fully sets before leaving the belt. Filtered air is thus trapped within the containers. The closed containers are discharged by means of a double turret 301 carrying pivoted cam-operated fingers 311 and guides 324. Specifications 470,098, [Group XVII], and 538,980, [Group XXX], are referred to.