| 摘要 |
402,434. Bending wood. HIRSCH-FIELD, A., 32, Holborn Viaduct, London. March 23, 1932, Nos. 8696 and 14510. [Class 145 (ii).] A tennis racket or similar frame is formed of separate laminations which are secured together by " dry " glue. This glue is caused to adhere by the application of heat and pressure which simultaneously bends the plies to the required shape. A composite structure from which a number of racket frames can be obtained by slicing is made of a laminated member framing the head ring 1 and handle 2, a central handle piece 12 and a wedge 3 composed of three or more pieces each laminated in themselvas and having a central rod 7a and a covering piece 8, 9. These elements are placed in a press, Fig. 8, with the requisite sheets of dry glue between them and the frame is then bent to shape by first closing the hydraulically operated platen 15 towards the central frame 14 and afterwards the platens 16, 17, 18 in pairs in the order named. Each platen is heated by steam coils to melt the glue. The former 14, which is also heated, is withdrawn vertically and is supported by recesses in the top and bottom plates of the press. The neck is secured by a rivet 29, Fig. 4. |
