GB1059583A - Improvements in or relating to apparatus for making cartons - Google Patents

Abstract

1,059,583. Making cartons; seaming non- metallic sheet material. WEYERHAEUSER CO. Oct. 18, 1963 [Oct. 18, 1962], No. 41339/63. Headings B5D and B5K. [Also in Division B8] Lateral flanges (14) (Fig. 1, not shown) on wall sections of one of a pair of crossed blanks of material with thermoplastic properties are turned inwardly to overlie wall sections (10) of the other blank by the flared mouth 34, Fig. 4, of a reciprocating female die 32 co - operating with a stationary male die 20 to set up the wall sections, and the flanges (14) and sections (10) are bonded together by heating means incorporated in holes (35) (Fig. 6, not shown) in the walls of the female die. The blanks, which are fed to the dies either singly, or in pairs each assembled in a conveyer pocket wherein they may be subject to radiant pre-heating, are initially clamped on the male die by a platen head 29, Fig. 4, also containing heating elements 30, and the wall sections 10 are turned inwardly before the wall sections 12 by an inwardly projecting pair of spring prongs (36) (Fig. 6). The female die 32 makes a short dwell at the bottom of its cycle to ensure complete bondage of the seams and the carton (see Division B8) is finally ejected by upward movement of a stripper plate 22 mounted on a hollow shaft 23 through which a blast of air is blown to complete the ejection. The male die 20 may be cooled by circulation of a coolant through a chamber 26. For heavy duty cartons the seams are reinforced by additional pressure at the carton edges due to engagement of longitudinal splines (39) (Fig. 11, not shown) in the female die within corresponding grooves (40) in the male die, causing the thermoplastic coatings of the blanks to bond round the edges of the wall sections 10. The carton material may be paperboard treated with thermoplastic material or fibrous sheet material faced with polyethylene or polypropylene film.