Patent GB-714941-A (GB)
Title: Method and apparatus for applying covering material to a molded article, for example, a portable typewriter case or an article of luggage
IPC: B29C63/04
Filed: 1952-01-07
Abstract: 714,941. Cabinets. HAWLEY, PRODUCTS CO. Jan. 7, 1952 [Jan. 25, 1951], No. 458/52 Class 52(1) [Also in Groups V and XVII] A blank of covering material is applied to a three-dimensional moulded article, e.g. a portable typewriter case or article of luggage, having rounded corners and edges, by applying adhesive to the article or to the blank or to both, placing the article on a male die member, positioning the blank over the article, advancing the male die into a complemental female die, pressing the blank into wrinkle-free contact with the article and overlapping the edges of the blank to form a wrinkle-free joint at the rounded corners and edges of the article. The article may have been made from an aqueous slurry of fibrous material, and may incorporate a resin, this resin being added to the slurry or being applied to the formed article and set by heating. The covering material may be plastic sheet or leather and the adhesive may be polyvinyl acetate. Fig. 3 shows a moulded article 50 having non-planar surfaces and rounded edges, to which a cover 51 has been applied by pressure between a female die 18 and a male die 29. The die 18 is stationary, being secured to the tops of rods 19, and includes a forming face 24, a heating chamber 23 and flanges 25 to which are secured cover-positioning members 27, 28. The die 29 includes a rigid perforated plates 40 over which is secured a resilient forming member 39. Fluid under pressure is delivered from a source not shown into space 48 within plate 40 and passes through perforations 49 to force member 39 outwardly. The die 29 is slidable vertically on rods 19, and is pushed up to the pressing position shown by a.hydraulic piston via shaft 45. Four plates co-operate with the dies in applying the covering to the article. Two of these plates 27 and 28, are secured to the underside of die 18, and the other two, 55 and 56, are secured to a draw ring 52 urged upwardly by springs 53 surrounding rods 19, or by a foot treadle. The plates 27, 28 have at their ends recesses 59 which seat around locating pins 64 fixed in ring 52; these plates are thinned out at their edges 57 and have corner notches 61. Fig. 2 shows the covering before application to the moulded article. The covering includes tabs 16 at the corners and side panels 13, 15. One panel 15 has a notch 17 for marking the position of the covering during its application Operation.-The adhesive having been applied, the moulded article 9 is placed on the. resilient face member 39, Fig. 7, and the cover 10 is superimposed thereon, the tabs 16 having been bent by hand to underlie the side panels. The cover lies under the plates 27, 28, but over the plates 55, 56, and is supported by pins 63 which retract against spring pressure when the dies are brought together. The inner die then rises, Fig. 9, end the plates 27, 28 press the two side panels 15 on the article. At the same time, Fig. 10, the other two side panels 13 are held out of engagement with the article by the plates 55, 56, which underlie the panels (see also Fig. 13). The inner die continues to rise and the panels 13 pass between the flange 25 on die 18 and the plates 55, 56 and are pressed on to the article, their edges lying on and overlapping the edges of panels 15. Compressed fluid then expands member 39 to press the article and covering together.