GB362820A - Improvements in and relating to a method of and mechanism for mechanically extracting the inter-connecting threads between stitched books - Google Patents

Abstract

362,820. Book - stitching machines. POLLAK, J. E., 20, Holborn, London.-(Brehmer, Geb. ; Plagwitz, Leipsic, Germany.) Nov. 14, 1930, No. 11830/31. Divided on 362,132. [Class 112.] The interconnecting threads between two stitched books are mechanically extracted by a member which forces the foremost book away from the remainder of the book pad after manual or mechanical severance of the thread of the idle stitch made between the complete books according to the method described in Specification 362,863. The book pad a, Fig. 1, is shown stitched in the usual manner with a row of looped stitches, the thread e, forming part of the idle stitch between the completely stitched book c and the remainder of the book pad a. When the thread e is severed, either manually or by the method described in Specification 362,863, it will remain looped with the loop hand will hang in the loop g of the adjoining stitch. The thread e must therefore be extracted from the loop h before the book can be separated. To this end, a separator member 23, Fig. 8, is passed between the completely stitched book c and bookpad a. The book signatures are fed to the stitching device by the carrier 11, Fig. 5, and an idle stitch formed after the completion of each book. The threads e of the idle stitch are engaged by selector members 18 down which they travel to encounter arms 14 which the threads rock to trip the parts 14a out of engagement with stops 22. This enables a spring to urge a bar carrying the separator members 23 to the right during which movement the bar is guided by cam-slots to a lower position to enable the members 23 to enter between the finished books the rest of the book pad 15 force the book awav and withdraw the threads e cut by the knives 23a, Fig. 8, forming part of the members 23. The withdrawal of the threads e tighten the last loop g of the stitching. The thread extracting mechanism is restored to initial position by the cam 28, roller 27 and arm 26. In the case of books stitched by a staggered stitch, Fig. 11, and having a backing strip, the cutter is in advance of the separator member and the book first separated slightly from the pad for cutting, and then completely separated for extracting the thread. Specification 362,828 also is referred to.