Patent GB-1243977-A (GB)
Title: Method and apparatus for producing filters containing filter granulate materials
Inventor: SCHUBERT BERNHARD
IPC: A24D3/02
Filed: 1967-09-05
Abstract: 1,243,977. Tobacco-smoke filters. HAUNI-WERKE KORBER & CO. K.G. 29 Aug., 1968 [5 Sept., 1967; 11 Sept., 1967; 10 Nov., 1967], Nos. 40466/67, 31305/67 and 6112/71. Heading A2C. In an apparatus for making tobaccosmoke filters comprising a granulate filter material confined between two stopper elements within a preformed tube, a stopper element, granulate material and a further stopper element are successively inserted into the ends of preformed tubes supported and conveyed in an upright position. In one embodiment preformed tubes 1 of filter case material and stopper forming rods 15 are simultaneously fed by concentrically mounted grooved feed drums 2, 7 respectively to a rotating filling drum 6 on which they are transported with their longitudinal axes vertical. Two plungers 3, 46, and a retaining groove 45 (for a rod 15) in the end of an arm 43 of a lever 39, are associated with each of a series of tuberetaining grooves 45 disposed around the periphery of the drum 6. The lower end of each groove 45 includes a protrusion 44 apertured to surround the whole periphery of a rod 15. Coaxial with and above each groove 27 are a receiving bore 26 and a measuring bore 36 separated by a narrow peripheral groove 37. Fixed cam rings 4, 47 and a cam disc 42 reciprocate the plungers 3, 46 and rock the levers 39 respectively during the rotation of the drum 6. In operation, after the simultaneous feeding of a tube 1 and a rod 15 to their respective grooves 27, 45, the associated plunger 3 is raised to slide the tube 1 into the receiving bore 26 and to support it there during the whole filling operation. Simultaneously plunger 46 is lowered and pushes the rod 15 along the groove 45 and through the aperture 66 to project therefrom so that one quarter of its length is inserted into the measuring bore 36. The rotation of the drum 6 carries the bore 36 past a circular cutter 8 which cuts off the quarter length to form a stopper element 61. During this cutting the plunger 46 is raised out of the groove 45. During further rotation of the drum 6 the lever 39 is rocked to move the remaining part (62) of the rod 15 out of the region between the bore 36 and the plunger 46, after which the plunger 46 is again lowered to push the element 61 through the bore 36 and through the tube 1 to the bottom thereof where it presses against the support plunger 3. The plunger 46 then withdraws and, as the bore 36 moves into a measuring region R (Fig. 1), a plate 63 (Fig. 5) comes to lie within the peripheral groove 37 to close the bottom of the measuring bore 36 which is then filled with filter granulate material from a magazine 12. As the bore moves away from the magazine 12 and past the end of the plate 63, the measured granulate 64 falls into the tube 1 aided by an electric vibrator 58. In similar manner, on further rotation of the drum 6, a double length stopper element 65 (half the length of the original rod 15) is cut off the remaining part (62) of the rod 15 by a cutter 9 and inserted in the tube 1 followed in turn by a second measured granulate filling 67 and a stopper element 66 comprising the remaiining quarter length of the rod 15 to complete a double length filter 68 comprising terminal stopper elements, a central double length stopper and two filter granulate fillings. Either the rods 15 or the tubes 1 are provided with narrow strips of thermoplastic adhesive running along their length at the periphery or on the inner side respectively, so that on moving the completed filter 68 past a heating drum 18 adjacent a grooved discharge drum 14 the stopper elements are stuck to the tubes 1. In a modification, the vibrator 58 is replaced by suction applied through a central bore in the support plunger. In another embodiment, the supporting and inserting plungers are all mounted in groups of four enabling four adjacent tubes on the filling drum to be taken through each stage of the filling process together.