GB404999A - Improvements in vulcanizing presses - Google Patents

Abstract

404,999. Vulcanizing tyres. MACBETH, C., 67, Norwich Union Chambers, Congreve Street, Birming- ham. June 25, 1932, No. 17972. [Class 70.] In a vulcanizing-press comprising a horizontal lower member, and hinged upper members, the opening, closing, and locking means comprise a power-operated toggle mechanism formed of main links connected to the top mould member by overhead links, and a power cylinder between this mould member, and the overhead link. At the back of a lower mould member C is a pedestal D to which are hinged intermediate and upper moulds B, A. The toggle linkage consists of links i trunnioned to the member C at i<1>, and i<2> trunnioned to the member A at i<3>. Mounted on the link i<2> is a double-acting cylinder g, the piston-rod of which is pivoted at g<2> on the front of the mould A. To open the mould, power is admitted to the back of the cylinder g, and the links swing from the closed position, Fig. 1, to that shown in Fig. 3. The swinging of the link i causes a cam i<4> bearing on a roller b<4> to separate the mould member B from C, while a cam surface j prevents the members B and A from sticking together. At the same time, a cam k operated through links k<1>, k<2> raises the hinge k<4> of the member B, and also, acting through links k<6>, k<5>, that of A, so that the initial open and final closing movements are parallel. When the hinges have reached their maximum lift, continued operation swings the member A into the position shown in Fig. 3. To raise the intermediate member B, a separate cylinder h operates a depending lever extension of the member. The apparatus may be locked when closed by a catch p controlled by a cylinder p<2> communicating with the interior of the tyre, so that the catch cannot be released while there is pressure in the tyre. In a modification a single mould is described. For small work, parallel opening and closing it not necessary ; the cam operated hinges may then be dispensed with.