| 摘要 |
1,243,009. Vulcanizing rubber. ENGLISH ELECTRIC CO. Ltd. 6 Dec., 1968 [9 Dec., 1967], No. 56105/67. Heading C3E. [Also in Division H5] Microwave heating apparatus, for preparing rubber sheet material 24 for vulcanization in a press 15, comprises an enclosure 1, 30, which is reciprocated relative to the stationary sheet to avoid hot spots, the usual mode stirrers 4, 52 being provided also. Chokes 13, 43 are provided at each end of the enclosure 1, 30, to prevent escape of microwave energy through the slots 12 through which the sheet material passes. A section of rubber conveyer belting 24, comprising several rubber-impregnated canvas plies bonded between rubber outer covers, is engaged and stretched between a gripper 22 and stretcher 23, microwave energy is supplied to enclosure 1, and a reciprocating unit 8 is operated to move the enclosure relative to the belting 24. The heated belting is then passed into the hydraulically-operated press 15, jacks 14, 19 operating in synchronism to keep the belting straight during pressing, between steam-heated platens 17, 18. Alternatively, the enclosure 30 comprises a number of cells 35 and is supported on a frame 31 pivotally attached at 32 and 34 to a pedestal 33 and a movable part of the press, respectively. A framework 36 for the enclosure 30 is oscillated by a mechanism 42 relative to frame 31, to move the enclosure 30 backwards and forwards, the framework 36 being on rollers 39 rolling in guides 40 of frame 31. The belting 24 is carried through the enclosure 30 on a continuous conveyer belt 44, transparent to microwave energy, and supported on a bed 50, also transparent to microwave energy. A preferred choke is described, Fig. 3 (not shown). |
