GB712748A - Improvements in or relating to plant or apparatus for cleaning or otherwise treatingarticles in baths containing liquids - Google Patents

Abstract

<PICT:0712748/III/1> <PICT:0712748/III/2> Apparatus for treating articles in baths containing liquids, such as degreasing baths, comprises means including an arm for supporting the articles and linking means for connecting the supporting means to driving means for oscillating the arm to shake supported articles in a lowered position within the bath, the driving means being adjustable or bodily movable for movement of the arm to convey the articles between the lowered position and a raised position. The apparatus shown in Fig. 1 comprises a rectangular frame 1 or platform adapted to carry perforated containers for the articles to be treated, the containers resting on flanges 3 and fitting between flanges 2. The frame 1 is supported by four boomerang-shaped arms 4 each of which is pivoted at one end to a corner of the platform and at the other to a side wall of the bath 6 near its top edge. The pivot pin of one of the arms 4 is secured outside the bath to an arm 11 forming with links 10, 9 a toggle linkage operated by the piston rod 8 of a pneumatically operated cylinder 7, the supply to which may be controlled so that, after a full stroke to lower the platform, it is reciprocated through a reduced stroke to oscillate the arm 11. The linkage may be duplicated on the opposite side of the tank or a separate piston and linkage may be arranged to rotate each of the arms 4. The articles are fed to and from the platform 1 by roller-conveyers 13, 14. The pneumatic control arrangements shown in Fig. 5 comprise a selector valve 19 operated in a manner to be described later and adapted to admit compressed air from inlet 16 through pipe 21 to either of two pipes 22, 23. If the platform is in its uppermost position and the connection is to pipe 22, a hand-operated valve 15 is opened to admit air to serve cylinder 31, the piston of which thereupon rocks arm 30 to actuate selector switch 25 to reverse the connections to the actuating cylinder 7. The space on the lower side 35 of the piston, previously connected to high pressure through pipe 26 is connected to exhaust through a valve 29, providing restriction in the direction of the arrow so as to allow the pressure to fall gradually. This permits the platform to fall, and pressure at the same time builds up in the space on the upper side 36 of the piston, which space has now been connected by the selector switch 25 to high pressure through pipe 26. Compressed air now gradually enters cylinder 20 on side 37 of its piston through restricting valve 33, the side 38 being connected to exhaust so as to actuate the piston to reverse selector valve 19. Pressure is thereupon applied through pipe 23 to serve cylinder 32, and cylinder 31 is connected to exhaust, the resistor arm 30 and selector valve 25 being restored to the position shown in Fig. 5. Pressure is now supplied to side 35 of the actuating cylinder 7 and side 36 is connected to exhaust. Reciprocation of the piston rod 8 now proceeds with a throw determined by the setting of the restrictions 33, 34; both of these restrictions are effective only in the direction shown by the arrows. On closing the hand-operated valve 15, high pressure air supply is cut off from cylinder 31, restoring selector valve 25 to the position shown, admitting pressure to side 35 of actuating cylinder 7 and causing the piston to raise the platform to the top of its travel. Hydraulic instead of pneumatic operating means may be employed. In a modification for operation mechanically one or more of the arms supporting the articles or container is connected by a link to an eccentric sleeve or cam follower of an eccentric or cam mounted so as to be moved bodily to raise or lower the articles or container and then rotated to produce the oscillatory motion.