Patent GB-653251-A (GB)
Title: Automatic press for the final shaping of objects of moulded cardboard
IPC: B31B50/59
Filed: 1947-08-27
Abstract: 653,251. Shaping cupped articles. MARGUERAT, G. Aug. 27, 1947, No. 23778. Convention date, May 19, 1943. [Class 100 (ii)] In an automatic press for the final shaping of objects of moulded cardboard by compression of the objects by fluid pressure exerted between a steel matrix and a flexible mandrel, the mandrel is brought into position within the object by mechanical means and the fluid pressure is applied only when the mandrel is in position. - As shown in Fig. 1, the press comprises a slide 31 carrying the expansible mandrel 33 reciprocable on a pair of parallel shafts, one of which is shown at 4, and which are mounted at one end on a support 1 and at the other end in a support 2 in which the matrix carrying head is mounted. Support 1 journals a driving shaft 6 on which are keyed three cams 7, 8, 9 which respectively move the expansible mandrel 33 into position, and operate hydraulic devices producing low and high pressures within a cylinder chamber 35 to effect compression of the object when matrix and mandrel are in operative position. Cam 7 co-acts with a follower 15 to oscillate a bell-crank 13, 10 and by a toggle lever 11 pivoted to the bellcrank at 12, moves the slide 31 so that the mandrel penetrates into the object to be compressed carried by the matrix. Cam 8 co-acts with a roller 17 on a bell-crank 16, 18 and by an intermediate toggle connection 21, 20, 23 and guide 22 drives a piston 25 of a cylinder 26 and thus forces fluid through piping 41, 45 into the chamber 35 in the slide 31 to effect the low pressure expansion of the mandrel. Cam 9 operates, through the medium of roller 28, a piston 29 of a cylinder 30 and drives the fluid through piping 41, 45 to subject the article between the matrix and mandrel to the high pressure. The hydraulic pressures are adjustable by means of the hand-operated piston and cylinder 42, 40. The head of the press is mounted to rotate in 120 degrees steps on a shaft 47 journalled in the support 2 and comprises three radial recesses seating steel matrices composed of half shells 52, 521 held in seating position by a spring-loaded ring 57. To facilitate their ejection after shaping the objects are thrust partially out of their seatings and separated from each other by means of a finger 53 operated by riding on a stationary cam 48 on the shaft 47. In a modification, Fig. 4, the toggle mechanism 10, 11, 12 is operated by a hydraulic jack 39 connected between the elbow of the toggle and a pivot 60 on the support 1. Pressure fluid is supplied to the jack 39 from a pump 38 which supplies a low pressure to operate the piston 61 and a high pressure for the compression of the object by the mandrel 33. The fluid is directed at the low pressure into the jack 39 by one position of a distributer 73 which is operated by a cam 75 and plunger 83, 81 and in the other position of the distributer, fluid is directed at the high pressure through telescopic tubes 74 into the slide 31 carrying the mandrel 33. The low-pressure fluid also operates a cylinder and piston 66, 65 to effect a step-by-step rotation of the matrix-carrying head by means of a rack-andpinion mechanism 67, 69.