Improvements relating to painting machines

摘要

A coating machine comprises a spray gun mounted on a carriage adapted to be moved in synchronism with a conveyer for the articles to be coated, and means for collecting excess coating material delivered by the gun. Referring to the drawings, shaft 15 carrying spokes 20 supporting turret rim 23 covered with sheet 24 and eave 25 is driven by motor 30 operating pinion 33 through speed reducer 31 and main drive shaft 32 driving sprocket 34 by means of chain 35. The rim 23 carries a plurality of spindles 40 supported on sleeve 41 fixed to rim 23 and carrying on the top of shaft 42 a demountable wheel chuck 44 and on the bottom a V-belt pulley 48, so that as the rim 23 rotates the pulley engages V-belt 52 and so rotates the spindles. A similar arrangement is shown at 60. The carriage 70 travelling in track 71 carries spray guns 74 to 77, and carriage 80 has guns 84 and 85. A spider 90 is rotatably mounted on shaft 15 and comprises arms 92 and 93 connected to carriages 70 and 80, a tie-rod 94 connecting these arms and a cam-follower 95 with roller 96 which co-operates with cam 100 on shaft 32, this cam having both a spiral displacement surface and a quick return surface. Spring 97 holds cam follower 95 against cam 100 and hence rotation of shaft 32 oscillates 70 along track 71, a piston 98, 99 easing the return of follower 95 on to cam 100. The spray guns are operated by compressed air supplied through valve 113 operated by cam follower 112 and cam 120 on shaft 32. The spraying operations are carried out in booths A and B disposed about turret 20. These booths comprise a ceiling 130 and side walls 131, the rear wall being an apron 132 of sheet material of the contour shown in Fig. 6 and having a small vertical wall extending across it adjacent its upper edge to provide a trough 135 receiving water from pipe 136 and allowing it to flow down the apron 132, thus forming a seal which removes excess spray and returns it to separating sump 152. Further excess spray is removed by the usual tower 140 and returned to the sump 152. The apparatus is particularly useful for painting automobile wheels.