Patent GB-1352848-A (GB)
Title: Web slitting apparatus and motion-transmitting apparatus therefor
IPC: B26D7/26
Filed: 1970-04-23
Abstract: 1352848 Cutting apparatus MASSON SCOTT THRISSELL ENG Ltd 22 April 1971 [23 April 1970] 19595/70 Heading B4B A carrier arrangement for cutting elements of a web slitting apparatus comprises a pair of carrier members 10, 14 the carrier member 14 being adapted to carry a knife 6 and the member 10 adapted to carry a counter member 7 against which the knife can cut a web 4 moved between the cutting elements, and confronting faces on the carrier members, the faces having rollers 21, 22 which when the carrier members are urged together interengage so as to oppose relative movement between the carrier members while permitting relative movement between the carrier members and a web engaged therebetween. The lower carrier member 10 is provided with rollers 15 arranged to run on a track 16 and the upper carrier member 14 with rollers 19 arranged to run on ribs 20 formed on a beam 18 which can be raised or lowered by means of pneumatic rams 24. During a slitting operation, the beam is raised so that the rollers are out of engagement with the web and the knife 6, which is pivotally mounted on an arm 12, is lowered so as to be in cutting engagement with the counter member 7. A splitter plate 26 is provided for separating the severed strips. In order to set the cutters to a different position across the width of the web, the beam is lowered so as to bring the rollers 21 on the upper carrier into engagement with the rollers 22 on the lower carrier thereby maintaining the relationship between the knife and counter member. The upper and lower carriers are then moved together across the web either manually or by means of an hydraulic or pneumatic ram connected to the lower carrier. In a modification a single set of interengaging rollers may be used. In order to prevent damage to the edge of the web when it is necessary to move a carrier assembly thereacross as shown at the L.H. side of Fig. 2, cam grooves are provided in the upper carrier for co-operation with pins 31 in the beam thereby causing one end of the upper carrier to be tilted so that the edge 23 of the web passes freely between the rollers; the other set of rollers 21, 22 are maintained in engagement so that alignment of the knives is maintained. In a modification, the cam-and-pin arrangement is dispensed with and the edge of the web is protected by means of a pair of tapes (40, 41), Fig. 3 (not shown), stretched across the width of the machine. Alternatively, endless belts (52, 54), Fig. 4 (not shown), are trained around their respective rollers 21 and 22 on the upper and lower carriers, additional idler rollers being provided on each carrier for the belts. In a further modification the rollers 21, 22 are replaced by pipes 60, 61 having perforations 62, 63 through which compressed air is fed thereby providing an air bearing enabling the carriers to be moved across the web. In a still further embodiment, the interengaging rollers may be replaced by balls in one member engaging with recesses in the other; alternatively one ball in one member may engage with three balls, arranged in triangular formation, in the other member.