Patent GB-538368-A (GB)
Abstract: 538,368. Sterilizers. HOBART MANUFACTURING CO. Jan. 27, 1940, No. 1697. Convention date, Feb. 1, 1939. [Class 1 (i)] [Also in Groups XXX and XXXVII] A device for sterilizing dishes, glassware &c. by means of ultra-violet or other germicidal rays comprises a casing divided by a partition for part of its length into front and rear compartments, a continuous horizontally-arranged conveyer moving in one direction along one side of the partition past reception and delivery openings provided in the rear wall of the casing, and moving in the opposite direction under and over sterilizing lamps provided in the front compartment. The casing comprises a base frame 10, Fig. 2, formed with cross-braces 11, end walls 15, Fig. 3, provided with windows, and removable combined front and rear walls and cover portions 22. The partition 53 separating the reception &c. compartment 51 from the sterilizing compartment 52 is provided with a glass window 56. Pivoted guards are provided to restrict the reception and delivery openings to those purposes, and the insertion compartment is provided with a drip tray 155. The conveyer is constituted by a series of wire members 81 attached by means of loops 82 to alternate links of a chain engaging sprocket wheels 90, 91, Fig. 4 ; along the straight portions of their travel the outer and inner ends of the wires move along grooved guides 44, 50, formed between plates supported respectively by posts 40 attached to the base frame and supports 46, 46a, rising from the cross-braces. At the end adjacent to the driven sprocket wheel 90 a guide 105 of semicircular form is afforded for the outer ends by plates 102 ... 104 clamped to the end wall, a correspondingly shaped guide for the inner ends being provided by rounding the ends of plates 47 ... 49. Sprocket wheel 91 is adjustably mounted on a bracket arm 135 slidable horizontally with respect to post 46 to provide means for keeping the chain taut ; this arm carries semicircular plates 132, 133, Fig. 6, forming with plate 134 a guide groove 145 for the outer ends of the wires in continuation of the side grooves 44. The inner ends are guided in a groove formed between auxiliary plates 146 ... 148 fastened to stud 138 so as to be movable with the sprocket wheel 91. Sprocket wheel 90 is driven from motor 110, Fig. 8, provided with speed-reducing mechanism 111 through means permitting temporary disengagement of the drive when resistance to the movement of the conveyer is experienced, followed by re-establishment on release of the obstruction. For this purpose the speed reducer is provided with a crank arm 113 carrying a drive plate 114 in engagement with a drive arm 120 on a worm shaft 118 meshing with a worm on the spindle 116 of sprocket wheel 90 ; spring means 121 on shaft 118 tends to maintain the drive, allowing the shaft 118 to move axially to interrupt it in the event of obstruction of the conveyer. A switch arm 160 extending through a slot 161 opposite to the delivery opening is contacted by any article not removed from the conveyer after passing through the sterilizing chamber, and being swung through an angle of about 75 degrees stops the conveyer ; this arm may be put out of action by being turned manually through 90 degrees to enable articles to be passed two or more times through the chamber. In compartment 52 a pair of lamps 60 providing the ultra-violet or other radiation are mounted above the conveyer and a single lamp beneath it, reflectors 70, 72, 73, 76 and 77 being provided to concentrate the radiation. The lamps are resiliently mounted in tubular sockets detachably carried by brackets attached to the casing. To prevent emergence of the sterilizing rays when the casing is open, a switch 183, Fig. 16, carried by a slidable tubular sleeve 176, is moved to the " off " position when either of the casing walls 22 is removed. The switch arm 184 is engaged between the inner ends of a slidable bolt 172 and a spring-controlled bolt 179 slidable in the sleeve. The electric circuits of the device are controlled from a main switch, the motor and lighting circuits being independentally controlled by the automatic means described above. The lamps are energized from a step-up transformer.