Patent GB-1010949-A (GB)
Title: Apparatus for surface treating articles
IPC: B24C3/18
Filed: 1962-07-09
Abstract: 1,010,949. Blasting; chucks. AJEM LABORATORIES Inc. July 9, 1962 [July 7, 1961], No. 26246/62. Headings B3B and B3D. Apparatus for surface treating articles comprises a rotatable carriage disposed within a housing and carrying a plurality of support means, each, adapted to carry one or more articles to be treated and including means for rotating the articles, indexing means for rotating said carriage in a step-by-step manner successively to position each support means at a plurality of stations disposed within the housing around the axis of rotation of the carriage and at at least some of which the articles carried by the support means are subjected to the action of treating means, partitions on the carriage between said support means and co-operating with means in said housing, when said. support means are positioned at said stations, to form separate compartments for the support means whilst at said stations, treating means at one or more of the stations for subjecting articles carried by the support means to the action of liquid jet or jets having particulate material entrained therein, and further treating means at other stations subsequent to said one or more stations for washing and drying said articles. De-burring and washing apparatus comprises a housing 1 with a recess 3 at the front having a platform 4 where a workman stands to mount workpieces 5 on supports 7. The latter are mounted at uniform angular spacing on a rotatable carriage 9 having a central column 11 the upper end of which is supported by a frame 13 above the roof 14 of the housing 1. The carriage 9 is rotated intermittently by indexing mechanism 15 so that the workpieces are carried in turn through a number of stations. When a workpiece has been carried through all the stations it arrives back at the recess 3 where the workman unloads it from its support and replaces it by an unprocessed workpiece. The following stations are provided: 17, unloading-loading; 18, first vestibule; 19, 20, first and second blasting; 21, flushdown; 22, second vestibule; 23, blow-off and 24, third vestibule. The stations are defined by partitions 27 carried by the carriage 9 and co-operating with partitions 29, carried by the housing 1 and partitions 29<SP>1</SP> carried by an inner housing 33 secured to the underside of the roof 14. Each partition 27 has on its outer edge a V-shaped resilient member 35; each partition 29, 29<SP>1</SP> has on its inner edge a pair of resilient members 37. A lip 45 on the housing 1 fits in a trough 41 on the carriage 9. A support 7 is mounted on the carriage 9 between each of the partitions 27. A spindle 49 is rotatably mounted in a tubular housing 48 secured to the wall 39 of the carriage 9 and is driven, through a belt 51, by a motor 52 mounted on the carriage wall 39 and normally energized by a switch 67 mounted on the trough 41. A hub 53 fixed to the spindle 49 carries baffles 54, 55 co-operating with a baffle 56. A push-rod 57 supported for axial movement in the spindle 49 has at one end a bolt 65 and lock-nut 70; the other end of the rod extends through a sleeve 59 and has a collar 59<SP>1</SP>. The bottom 61 of a soft rubber cup 58 fits into a groove in the collar 59<SP>1</SP> and is clamped by nut 62. The cup 58 is engaged by a rib 60 on the sleeve 59, and an annular flange 63 on the cup 58 is clamped against the hub 53 by a ring 64. The rod 57 is urged by a spring 66 to cause the cup 58 to grip a bore in a workpiece 5. When the support is at the load-unload station 17, the push-rod 57 can be moved to release the workpiece by a rocker arm 71 engageable with the bolt 65 and actuated by an hydraulic motor 143 controlled by a chuck " off button 151 and a chuck " on " button 153, both in the recess 3. A control bar 149 opens the switch 67 of the motor 52 of the support which is at the station 17 to stop rotation of the support. The column 11 has at its lower end a stub shaft 72 mounted in bearings 73 and at its upper end a stub shaft 78 mounted in bearings 79. A stopping wheel 83 is secured to the top of column 11. An arm 85 pivoted on the shaft 78 is swung by an indexing hydraulic jack 103. An indexing pin cylinder 88 is mounted on the swing arm 85; the piston pin 91 passes through a hole in arm 85 and when extended passes also through one of the holes 89 in the stepping wheel 83. A locking pin cylinder 97 is mounted on the frame 13 and its piston pin 99, which has a bullet-shaped end, when extended engages one of the holes 89 in the stepping wheel 83. To effect indexing, locking pin 99 is retracted to disengage the stepping wheel 83, indexing pin 91 is extended to engage the stepping wheel 83 and arm 85 is swung against stop 107: locking pin 99 is extended to engage the stepping wheel 83, indexing pin 91 is retracted to disengage the stepping wheel 83 and arm 85 is returned against stop 109. Below the blasting stations 19, 20 and flushdown station 21 is a sump 111 containing liquid and particles. A manifold 113 supplies liquid under pressure to blast nozzles 115 below the blasting stations 19, 20. Particles settling in the bottom of the sump are entrained in the jets emerging from the nozzles 115. Ejector tubes 117 register with the nozzles and are held at selected angles. The entraining liquid, spent articles and material removed from the workpieces fall back into the sump. The re-usable particles settle to the bottom of the sump; lighter particles are carried away by liquid overflowing the edge of the sump. A baffle arrangement 125 is provided near the edge of the sump. The overflow liquid passes into a trough 131 which slopes around the sump 111 towards a settling tank 133. In the flushdown station 21 the workpiece is subjected to jets of washing liquid directed from a manifold positioned above the level of the liquid in the sump 111, the liquid and removed contaminants draining back into the sump 111. A motor-driven, large capacity, high pressure pump 155 draws from the settling tank 133 and supplies the blast manifold 113 and flushdown manifold. A by-pass pipe 163 leading back to the settling tank 133 is controlled by a diverting valve 161 operated by an hydraulic jack 167. During indexing, the liquid is passed back to the settling tank. Liquid can be drained from the manifolds through a pipe 166 having a normally closed valve 169. The settling tank 133 can be similarly drained. Access doors 172, 172a are provided, e.g. for cleaning out the settling tank 133. In the blow-off station 23 the workpiece is subjected to strong air blasts from nozzles 137 on a vertical manifold 135 and a horizontal manifold 135, both supplied by a motor-driven fan 141; exhaust louvres 140 are provided in the roof 14. The hydraulic jacks 88, 97, 103, 143, 167 are controlled by valves 197, 195, 193, 191 operated by solenoids A-H. Cycle.-Assuming that the chucking jack 143 has been extended to render the chuck at station 17 inoperative, and that a workpiece has been placed on the chuck, button 151 is pressed, energizing solenoid C operating valve 193 retracting chucking jack 143 so that the workpiece is gripped. When jack 143 is fully retracted, it closes switch LS-1 in series with already closed switches LS-4, LS-6, and normally open button switches 200; when the operator closes switches 200, requiring both hands, solenoid H is energized operating valve 197 retracting locking pin jack 97 and extending indexing pin jack 88. When the jacks are fully retracted and extended respectively they close switches LS-2a, LS-3b, energizing solenoid F operating valve 195 retracting indexing jack 103 whereby the carriage 9 is indexed. When the jack is fully retracted it opens switch LS-4 de-energizing solenoid H, and closes switch LS-5 energizing solenoid G; valve 197 is operated extending locking pin jack 97 and retracting indexing pin jack 88. When the jacks are fully extended and retracted respectively they close switches LS-2b, LS-3a energizing solenoid B operating valve 191 extending blast-and-flush jack 167 so that valve 161 now supplies pressure liquid to the blast and flushdown manifolds. When the jack is fully extended it closes a switch LS-15 energizing solenoid E operating valve 195 extending indexing jack 103 to set up subsequent indexing. When the jack is fully extended it closes switch LS-4, but since switch LS-6 was opened when blast-and-flush jack 167 was extended and button switches 200 are open, solenoid H is not energized. Closure of the switch LS-15 also energizes a timer 201 to control the duration of the dwell at each station and a spring-operated safety timer 211 which after a time in excess of the normal time shuts down the whole apparatus to prevent damage of the workpieces and waste of materials. When the timer 201 times out it energizes solenoid A operating valve 191 retracting blast-and-flush jack 167 so that valve 161 by-passes pressure liquid to the settling tank 133. When the jack is fully retracted it closes switch LS-6. The chuck "off" switch 153 is then pressed energizing solenoid D operating valve 193 extending chucking jack 143 so that the workpiece on the support in the station 17 is released. The workpiece is replaced by a fresh workpiece, the chuck " on " switch 151 is pressed, the switches 200, 200 closed whereupon the next cycle commences when the timer 201 has timed-out.