GB957661A - Improvements in tension lockup apparatus for printing apparatus - Google Patents

Abstract

957,661. Printing surfaces. WOOD NEWSPAPER MACHINERY CORPORATION. Dec. 31, 1962 [March 19, 1962], No. 49125/62. Heading B6C. An apparatus for securing a stereotype printing plate to a printing cylinder by plate tensioning fingers, the fingers being operated by a member which is rotatable and movable along its longitudinal axis, includes Belleville springs for exerting a predetermined minimum of pressure of the fingers independent of rotation of the operating member beyond a predetermined position. The printing cylinder 1 shown has four pairs of longitudinally adjacent printing plates P each having underside recesses 9 for receiving plate engaging fingers 5 and 7. The fingers associated with the four plates on each side of the centre of the cylinder 1 as viewed in Fig. 1 are operated from the associated cylinder and, the apparatus at each end being identical although displaced relatively by 90 degrees. The fingers 7 for one edge of the plate P as viewed in Fig. 3 on the left are fixedly mounted on a shaft 8 which is positioned by adjustment of screws 50 and 51. Similar fingers 7 for the plate edge in axial alignment with the said plate of Fig. 3 are also mounted on a shaft 8 but this shaft is adjusted by screws 50 and 51 located in the central peripheral region of the cylinder. The fingers 5 for engaging one edge of the plate as viewed in Fig. 3 to the right are attached to a hollow shaft 13 on which is mounted a gear 17 which meshes with a worm gear 21 on a member 21<SP>1</SP> rotatably mounted in thrust bearings 25, 25<SP>1</SP>. A pre-stressed Belleville spring 26 acting between a member 29 and a collar 27 urges the member 211 to the right as viewed in Fig. 3. The member has a portion on which a handle may be fitted. Rotation of the member initially causes rotation of the fingers 5 to clamp the associated plate on the cylinder but after a predetermined pressure is exerted by the fingers 5 further rotation of member 21<SP>1</SP> causes compression of the spring. The spring thus serves to take up any wear in the plate recesses engaged by the fingers and to ensure a predetermined minimum pressure being exerted by the fingers on the plate. The pre-stressing of the spring may be adjusted through actuation of a spring setting plug 30 whilst an adjustable stop 32 limits axial movement of the member 21<SP>1</SP>. Similar fingers 5 are provided on a shaft 11 for engagement in the recesses on the plate edge in axial alignment with said right-hand viewed plate of Fig. 3. An extension of the shaft 11 passes through the shaft 13 and carries a gear 15 meshing with a worm gear 19. The apparatus associated with this gear is identical to that described above with reference to the gear 21. Specification 852,167 is referred to.