| 摘要 |
884,979. Forming metal foil caps. FORDS (FlNSBURY) Ltd. Jan.21, 1958 [Jan.24, 1957; Oct. 21, 1957], Nos. 2598/57 and 32796/57. Class 100(2) [Also in Group XVII] Apparatus for forming a metal foil cap of the type described in Specification 857,668 comprises male and female tools including grooved annular former bodies between which a circular foil blank is fed, means for moving the former bodies together so as to press an outer annular area of the blank between them, means for moving a forming. plunger mounted within the male tool through the aperture in the female former body, means for relaxing the pressure between the former bodies slightly before completion of the forming stroke of the plunger, means for separating the former bodies, means for retaining the formed cap on one of the tools and means for ejecting the formed cap after complete separation of the tools. The male tool set comprises a cylindrical carrier member 1 slidable within a sleeve 3 secured to a fixed part of the machine. A transverse wall 2 of the carrier 1 supports an annular blanking punch 4 and the shaft 25 of a plunger 26. A stripper ring 10 mounted on a sleeve 11 is slidable relatively to the punch 4 and is biased to the position shown by a spring 13. A former body 16 having a shank 17 slidably mounted on the plunger shaft 25 has an annular, radially ribbed working face and an ejector ring 19 urged resiliently outwards by a spring 21. The female tool set comprises a former body 80 and a blanking die 77 carried in a die housing 73 secured to the sleeve 3. The former body 80 has a series of radial slots 96, see Fig. 4, cut in the face thereof in which are located ribs 97: an inner member 81 secured in the former 80 has a slightly tapering bore 82 and ribs 98 coplanar with the ribs 97 but slanted at an angle thereto and twisted slightly so as to turn over and flatten the pleats at the radiussed transition portion between the "crown" and the "brim" of the capsule. An ejector.85 is mounted in the bore 82 and urged outwards by a spring 87. A removable embossing die 90 is fastened in the front face of the ejector. A strip of foil 72 is fed intermittently between the tool sets through cut-out portions 71 of the sleeve 3. A boss 28 on the rear face of the wall 2 of the carrier 1 is pivoted by a gudgeon pin 31 to a piston rod 30 rigidly connected to a journal rod 59 on which the journal 60 is located round a pin 61 on an eccentric 62 secured to the main operating shaft 63 of the machine. Two push-rods 33, one above and one below the piston rod 30 are slidable in slots in the gudgeon pin 31 and apertures in the wall 2 and abut at one end a plate 24 carried by the rear end of the male former body shank 17 and at the other rollers 34 carried by links 35 which are pivoted at 36 to an extension of the piston rod 30. The other ends of the links 35 are pivoted to a sleeve 39 slidable in a bearing 42 on a bracket 40 fastened to the piston rod. Slidable in the bore 43 of the sleeve 39 is a rod 45 which is restrained against withdrawal from the sleeve by engagement with the bearing 42 of a laterally projecting pin carried thereby and projecting through slots in the wall of the sleeve 39. A collar 49 on the rod 45 provides abutments for two compression springs 52, 53 the other ends of which respectively abut a shoulder 48 on the sleeve 39 and the bearing 42. The other end of the rod 42 is pivoted to a link 56 which is itself pivoted at 57 to an extension 58 of the journal rod 59 and on which is mounted a cam follower 65. The cam follower 65 engages the periphery of a cam 64 secured to the pin 61 and is held in contact therewith by the spring 53. Rotation of the shaft 63 moves the carrier 1 towards the female tool set until the stripper ring 10 engages the blanking die 77 and the former body 16 forces the foil 72 against the former body 80. Continued rotation of the shaft 63 causes the punch 4 to cut out a foil blank and the plunger 26 to draw the blank into the bore 82 of the crimping tool 80, the former 16 being forced back towards the wall 2 as the plunger advances. The pressure exerted by the former 16 depends upon the compression of the spring 52 which is governed by the position of the stop 49. The shape of the cam 64 is such that the pressure is relaxed slightly before completion of the stroke of the plunger. As the shaft 63 is rotated further and the direction of movement of the carrier 1 changes the cam 64 allows the stop 49 to be moved sharply to the right in relation to the piston rod 30 thus releasing all pressure between the formers 16, 80. Thus as the male tool set moves away from the female set the plunger 26 is still advanced beyond the working face of the former body 16, the formed cap being held in contact with the plunger by the ejector 85. As soon as the plunger clears the ejector, however, a rise R on the cam 64 causes the tool 16 to be advanced and to eject the cap from the plunger, the ejector ring 19 serving to eject the cap from the ribs of the tool itself. The upper end of the cap is embossed by the die 90 which cooperates with a resilient pad fixed in the front end of the plunger 26. |
