GB865432A - Tobacco smoke filter manufacture - Google Patents

Abstract

865,432. Making cigarette filters. LORILLARD CO., P. Nov. 27, 1958 [Jan. 3, 1958], No. 38323/58. Class 130. [Also in Group IX] Hooked pins 32, Fig. 3, mounted in helically wound strips 34, Fig. 2, of tape on a roller 30, Fig. 1, so as to pierce a moving band 17 of crimped 1 to 10 denier cellulose acetate filaments, catch and break a predetermined proportion, e.g. between 5% and 30%, of the filaments on retraction therefrom, the severed filament ends taking up heterogeneous angles relative to the band axis. The band 17 is tensioned between roller pairs 21a, 21b and 27a, 27b so as wholly or partially to remove the crimps during filament breakage, the roller 27a being driven slightly faster than the roller 21a, via a variable-speed gear 29 interposed between it and the common driving motor 23. After passing the rollers 27a, 27b, the band 17 is wholly or partly relieved of tension to allow the crimps to return and may first pass through a booth 43 where it is sprayed on both surfaces with dibutyl phthalate, triacetate, triacetin, triethyl citrate or other odourless and tasteless plasticizer, or an adhesive-like cellulose acetate, so that its filaments become tacky and adhere at their points of contact after tension relief. The booth 43 may precede the rollers 27a, 27b, when a further tensioning roller pair 44a, 44b is dispensed with. The band 17 is then passed as a bundle 17<SP>1</SP> into a machine 45 for making compressed and paperwrapped cigarette filter plugs, e.g. as in Specification 725,471, preferably having feed rolls which allow the tension on the bundle 17<SP>1</SP> to be adjusted. The band 17 is formed from a bundle 14 by an air blast from a perforated table 15 and by rollers 18a, 18b, freely rotatable apart from being braked by an oil pump 25 or friction brake. The rollers 18a, 18b and 21a, 21b, respectively, have intermeshing axial corrugations, or the roller 21b may be rubbersurfaced. The rollers 27a, 27b may be similarly corrugated, or the roller 27b or both rollers may be rubber-surfaced. The rollers 21b, 27b are held against stops by springs 24, 24b yielding on overload. Fixed guides 26, 31 are provided. The roller 30 is freely rotatable apart from being braked by an oil pump 35 or friction brake; and the angle its axis makes with the band axis is adjustable by moving one bearing 38, Fig. 2, along a slot 41 about the other bearing 36 as a pivot, so varying the effectiveness of the pins 33; alternatively or additionally the helical pitch of the strips 34 may be altered. The roller 30 may be mounted above the band 17 or may be followed by a like roller 30 above or below the band or by a roller with straight pins 32. U.S.A. Specification 2,794,239 also is referred to.