Apparatus for surface coating of small parts

1. A device for surface coating of small parts comprising a facility ( 10 ) with multiple processing stations ( 11 through 14 ) arranged sequentially in the processing direction, in which respectively one of multiple perforated drums filled with small part ( 1 a through 1 m ) are stepwise conveyed via a longitudinal conveyor ( 27 ) and by means of a disengageable drive are brought into rotation, wherein the first station ( 11 ) includes dip bath ( 21 ), filled with a liquid coating material, in which the drum ( 1 e ) is lowered with slow rotation via a lift device, the second station ( 12 ) includes a drip pan ( 22 ) for catching the excess coating material dripping during slow rotation of the drum ( 1 f ), the third station ( 13 ) is provided with a rapidly rotating drive in the manner of a centrifuge and the fourth station ( 14 ) includes a device for opening and emptying drums ( 1 h ) and a pallet ( 24 ) for receiving the coated small parts.

2. A device according to claim 1 , wherein between the fourth station ( 14 ) and the first station ( 11 ) a conveyor ( 40 ) is provided for return transport of the emptied drums ( 1 i , 1 k , 1 l ) as well as a filling device ( 30 ) for charging the drums ( 1 a through 1 d ) with small parts.

3. A device according to claim 2 , wherein the filling device includes a round table ( 30 ) rotating stepwise with a first station ( 31 ) for locking in and rotating the open drum ( 1 a ) in a position which makes filling possible, with a second station ( 32 ) for filling the open drum ( 1 b ), with a third station ( 33 ) for closing and rotating the drums ( 33 ) in a position which makes possible the advancement and rotation of the drums ( 33 ) as well as a fourth station ( 34 ), from which the drum ( 1 d ) properly oriented, is passed to the first station ( 11 ) of the facility ( 10 ).

4. A device according to claim 3 , wherein the device or, as the case may be, the round table, includes multiple stations with the same function, which are arranged sequentially in the direction of processing.

5. A device according to claim 2 , wherein in the path of the return transport conveyor ( 40 ) a cleaning facility is provided for the automatic cleaning of the emptied and opened drums ( 1 i through 1 l ).

6. A device according to claim 5 , wherein the cleaning device includes water jets, with which water is sprayed with high pressure of preferably 1200 bar against the drums.

7. A device according to claim 5 , wherein the cleaning device includes ultrasound emitters for producing ultrasound effective for cleaning the drums.

8. A device according to one of claim 1 , wherein the drums ( 1 ) are comprised of two mirror-symmetric half shells ( 2 , 3 ), which are provided axially displaceable but fixed against rotation on an axle ( 4 ) and which via a thrust mechanism are slideable towards each other and away from each other.

9. A device according to claim 1 , wherein the drum axle ( 4 ) projects from both sides of the half shells ( 2 , 3 ) and the projecting ends ( 4 a, b ) are in operable communication with the longitudinal conveyor ( 27 ) and can be brought into rotational connection with each rotation drive ( 2 , 29 ) provided in each station.

10. A device according to claim 1 , wherein the longitudinal conveyor ( 27 ) comprises lift beams ( 25 ) provided on both sides of the facility and are mounted transversally displaceable in guide rails ( 28 ), and the lift beams ( 25 ) include upwardly open axle receptacles ( 26 ) spaced apart from the stations ( 11 through 14 ), in which the drums ( 1 ) can be hung-in via their axle ends ( 4 a, b ) projecting from the sides.

11. A device according to claim 1 , wherein the drum shells ( 2 , 3 ) in cross section are multi-sided, preferably hexagonal, and in diagonal section are trapezoid shaped, wherein the drum shells ( 2 , 3 ) with their longer trapezoid sides face each other.