downwardly when the outer frame 72 is put on it in order to prevent this a vacuum holding device 99 for the sword 80 is provided in the outer frame 72 as shown in fig1 to 15 a carrier plate 100 is secured on the upper side of the outer frame 72 by means of screws 101 a suction plate 102 is suspended from this carrier plate for this purpose the suction plate 102 has a plurality of and preferably three upwardly projecting threaded bolts 103 which project through corresponding bores 104 in the carrier plate 100 preloaded compression springs 105 are arranged on the threaded bolts between the suction plate 102 and the carrier plate 100 knurled nuts 106 serving as adjusting elements are screwed down on the threaded bolts 103 the maximum distance between the suction plate 102 and carrier plate 100 is set by means of these knurled nuts 106 adjustment of the suction plate 102 relative to the sword 80 can therefore take place in the lower side of the suction plate 102 there is formed a suction chamber 107 which is open towards the sword 80 i e downward and which is connected to a suction line 108 arranged in the central longitudinal axis 109 of the outer frame 72 and thus of the sword 80 is a lifting drive 110 which comprises a small pneumatically actuatable piston cylinder drive an overhanging arm 112 of the suction plate 102 rests on the free end of the piston rod 111 of this lifting drive 110 as a result of pneumatic actuation of the lifting drive 110 and consequent.