Patent GB-560843-A (GB)
Title: Improvements in the making of protective coverings for wearing apparel
IPC: B29C51/00
Filed: 1942-07-06
Abstract: 560,843. Hat covers, linings &c. WEIKERT, R. J. July 6, 1942, No. 9340. [Class 63] [Also in Groups V, VIII, and XXIX] A sheet of rubber-hydrochloride composition is clamped between two members which leave the central part of the sheet unsupported, one or both sides of the central part is or are subjected to the action of a moist heating medium, e.g. wet steam, and one side of the central part is subjected to pressure to stretch it into the shape of, e.g. a hat covering or lining. The sheet may be of " Pliofilm " (Registered Trade Mark). Apparatus.comprises a stationary plate 3 having an oval central opening below which is mounted a steam chest 4a. A clamping plate 4 having a similar central opening and a plungercarrying plate 14 both slide vertically on.guides 2. Plate 4 is raised by means of a handle. 5 through links 6, 8, fast on a shaft 7, and links 10. Plate 14 may be lowered separately by means of handle 18, arms 19 integral with a loose sleeve 20, and links 16. Links 10, 16 are bowed so that handle 5 can be rocked upwardly beyond a dead-centre position, whereby the plates are held raised. A saw-toothed knife 26, fixed in a recess 31 in the plate 3, co-operates with a groove 27 in the plate 4. (When a wide brim is required, the recess 32 and groove 27a are used.) Operations : (1) The plates 4, 14 are raised from the position shown in Fig. 1 to their uppermost position. (2) A sheet of " Pliofilm " is fed in over the plate 3, the knife 26 being masked by sponge-rubber rings 28, 29. (3) The ,plate 4 is lowered, whereupon the plate presses back the sponge-rubber rings and a hat blank 66 is cut out and clamped between plates 3, 4. (4) Handle 18 is lowered and the plunger 21 descends. At the beginning of the descend, a cam 34 on the sleeve 20 opens a steam valve 36, and steam travels through pipe 33 to steam chest 4a and conditions the blank clamped across the mouth thereof. Just before the bottom of the descent, the cam 34 allows the valve 36 to close. At'the .bottom of the descent (Fig. 1), when the 'plunger has. shaped the blank, a cam 53 on the sleeve 20 opens a vacuum valve 49, whereupon vacuum is transmitted through pipe 48 to a recess 51 'in the plate 4, and thence by channels (not shown) to the space between the plunger 21 and the shaped blank. Perforations may be made in the blank by depressing a handle 25. (5) The whole assembly of plunger, shaped blank, and plates is raised by rocking handle 5 (towards the observer, Fig. 1). At the upper limit of the ascent, the cam 53 allows 'the vacuum valve to close, and the cooled shaped blank is removed. The steam valve remains closed during the ascent. The valve 36 comprises a member 41 normally spring-urged to closing position. To open the valve, a cam surface 37 on cam 34 engages follower 38 on lever 39 pivoted on lever 42, pivoted at a fixed point 43. The valve closes when follower 38 drops off the camsurface end 46. On the return movement of the cam, the end 46 rocks lever 38 idly in a groove in lever 42. The valve 49 also comprises a spring-urged closing member 60. The cam 53 comprises a member 57 urged by a spring into contact with the cam. Pins 54, 55 rock member 57, with lost motion, so that member 60 either rests in a recess 59 or rides down a ramp 58 on the member 57.