MULTIPLE GROOVED VACUUM COUPLING
The present invention relates to a coupling system ( 10 ) to releasably clamp a cylindrical target ( 12 ) to a spindle ( 14 ) by means of an interface ring ( 22 ) and a clamping ring ( 26 ), whereby the interface ring ( 22 ) and the cylindrical target ( 12 ) have engaging surfaces comprising two or more circular grooves ( 18 ). In another embodiment the clamping ring and the interface ring are the same piece. The advantage of the present coupling system is that it allows a square fitting and avoids high mechanical stresses.
1 . A coupling system to releasably affix a cylindrical target to a spindle, said coupling system comprising:
a) a spindle having a flange portion;
b) a cylindrical target having an end portion abutting against said flange portion of said spindle, said end portion having an outer circumferential surface;
c) an interface ring having an inner circumferential surface adapted to engage with said outer circumferential surface of said end portion, and a flange extremity abutting against said flange portion of said spindle;
d) tightening means for tightening said cylindrical target to said spindle via said interface ring;
wherein
said end portion has two or more separate circular grooves which engage with said inner circumferential surface of said interface ring.
2 . A coupling system according to claim 1 , wherein said end portion has three or more separate circular grooves.
3 . A coupling system according to claim 1 , wherein said tightening means comprise a clamping ring adapted to engage at one side with said interface ring and at another side with said spindle.
4 . A coupling system according to claim 1 , wherein said two or more separate circular grooves are made by machining in said cylindrical target.
5 . A coupling system according to claim 3 , wherein said clamping ring is made out of two or more clamping ring segments and said interface ring of two or more interface ring segments.
6 . A coupling system according to claim 5 , wherein the joins of the interface ring segments are covered by clamping ring segments.
7 . A coupling system according to claim 5 , wherein said clamping ring segments form each one single piece with said interface ring segments.
8 . A coupling system according to claim 1 , wherein said circular grooves have different depths, the greater depth being at the side of said cylindrical target.
9 . A coupling system according to claim 1 , wherein said circular grooves are made by two or more separate rings positioned on said end portion of said target and forming said outer circumferential surface.
10 . A coupling system according to claim 3 , further comprising a sealing ring between said interface ring and said clamping ring.
11 . A coupling system according to claim 1 , wherein said circular grooves have a rounded, rectangular or conical shape.
12 . A coupling system according to claim 5 , wherein each interface ring segment forms one piece with a clamping ring segment, said clamping ring segment shiftedly connected to said interface ring segment.
13 . A coupling system to releasably affix a cylindrical target to a spindle, said coupling system comprising:
a) a spindle having a flange portion;
b) a cylindrical target having at its end an outer circumferential surface and an end portion abutting against said flange portion of said spindle;
c) clamping means for clamping said cylindrical target to said spindle, said clamping means having an inner circumferential surface;
wherein
said outer circumferential surface of said cylindrical target has two or more separate circular grooves adapted to engage with said inner circumferential surface of said clamping means.
14 . A cylindrical target adapted to work with the coupling of claim 1 , said cylindrical target comprising an end portion, said end portion having an outer circumferential surface, said outer circumferential surface having two or more separate circular grooves.
15 . A backing tube suitable for use in a cylindrical target, said backing tube being adapted to work with the coupling of claim 1 , said backing tube therefore comprising an end portion, said end portion having an outer circumferential surface, said outer circumferential surface having two or more separate circular grooves.
16 . An interface ring adapted to work with the coupling of claim 1 , said interface ring having an inner circumferential surface, said inner circumferential surface being adapted to engage with two or more separate circular grooves in the outer circumference of the end portion of a cylindrical target.