Patent GB-1175602-A (GB)
Title: Workpiece Conveyor System
IPC: B24C3/08
Filed: 1967-03-16
Abstract: 1,175,602. Blasting. PANGBORN CORP. 16 March, 1967 [19 April, 1966], No. 12398/67. Heading B3D. [Also in Division B7] A workpiece conveyer system, for guiding a workpiece 11, Fig. 1, through an area 18, where it is treated by abrasive blasting by blast wheels 20, comprises a trolley 10 supported by wheel pairs 78, 80 from an overhead monorail 12, a workpiece engaging hook 66 on the trolley for holding the workpiece 11 and for rotating it about a vertical axis or alternatively about a horizontal axis, as it is treated by the blast wheels, and an independent drivemeans, e.g. an electric motor 26, Figs. 2, 3 and 4, mounted on the trolley for moving the trolley along the rail and, when required, for rotating the workpiece hook 66. Rollers 82 on the top of the trolley engage the underside of the rail 12 and lower rollers 84 on the trolley are adapted to engage plates 86 on the sides of an upper opening in the treatment area 18 the rollers maintaining the verticality of the workpiece hook 66. The motor 26, which is supplied with electric current from a bus-bar 28, Fig. 3, and collectors 30, drives a forward motion system for the trolley and which comprises a clutch 32, a brake 34, electric switch 36, cam 38 and retractable stop mechanism 40. The switch 36, which is operable when desired e.g. at an automatic loading station 14, a dwell station or at an automatic unloading station 24, controls the clutch 32 and brake 34 with respect to the motor 26. The stop 40 includes an extendable stop member operable by a fluid pressure cylinder. The stop is retracted by the operation of a valve under the control of a timer started by the operation of another valve controlled by the cam 38 on top of the trolley, whereby the switch 36 can be released to allow the trolley to provide to the dwell station as described with reference to Fig. 4a (not shown). The motor 26 also drives a rotary drive system for the work hook 66 and which comprises a clutch 54, brake 56, electric switches 58, 60, preset cam 62 and a cam 64, Fig. 1, in the area 18 for actuating the switch 58. The hook 66 does not rotate until it enters the treating area 18. When the switch is operated in the area 18 the brake 56 is disengaged and the clutch 54 engaged to rotate the hook 66. Rotation is stopped by the switch 60 and cam 62. The latter ensures that the hook is correctly orientated for unloading. In a modified trolley the hook can be rotated at high or low speed by separate motors as described with reference to Fig. 5 (not shown). Also the hook is provided with a solenoid operated clamp and the clamp may be adjusted for vertical position on the hook 66 by a rack and pinion mechanism operable from the motor 26, as described with reference to Figs. 6 and 7 (not shown). The treating area 18 has an entrance vestibule 16 and an exit vestibule 22. Both vestibules have two sets of doors arranged so that when one set is closed the other set is open to thus ensure that debris does not escape from the area 18 when a workpiece is admitted to or leaves the area. The blasting wheels are movable vertically relative to sealing plates as described with reference to Figs. 8 and 10 (not shown). The forward motion of the trolley in the treatment area 18 is effected by a drag chain or chains provided with dogs detachably connectible with the trolley as described with reference to Figs. 12 to 14 (not shown). At this time the forward drive system on the trolley is rendered inoperative by the operation of an electric switch 124, Fig. 4, which also engages the cam 64. The drive arrangements in the area 18 may be such as to move the workpieces back and forth and have dwell periods all as described with reference to Figs. 15 to 20 (not shown). The workpiece may be rotated about a horizontal axis as described with reference to Figs. 21 to 24 (not shown).