GB1178228A - Expanding mandrels. - Google Patents

Abstract

1,178,228. Winding mandrels. E. W. BLISS CO. 23 Aug., 1968 [18 Oct., 1967], No. 40385/68. Heading F2U. An expanding winding mandrel has segments 50, Fig. 4, expandable outwardly relative to a fixed portion 14, Fig. 1, and sheet material securing means which comprise a stationary gripper jaw 86 in one segment, a rotatable gripper jaw 92 in the same segment and operating means, connected between the non-movable portion and the rotatable gripper jaw, automatically rotating the gripper jaw in a clamping direction when the segment is expanded outwardly. When rod 32, Fig. 1, is moved axially by a mechanism (not described) a spider member secured thereto and engaged at its radial ends with outer wedge bars 26 moves the latter axially along inner wedge bars 18 so that the engagement of ramps 24, 28 causes the outer wedge bars 26 to move radially inwardly or outwardly. The outer wedge bars 26 have inclined surfaces (30), Fig. 3 (not shown), which engage corresponding surfaces (50) of spring-loaded segments (48) and 50 which thereby move inwardly or outwardly with the outer wedge bars 26. Each segment 50 has the hardened stationary gripper jaw 86 in an insert 84 and a further insert 88 mounting the rotatable gripper member 92 having a shaft portion 94 and a jaw portion 96. The shaft portion 94 has at its left-hand end in Fig. 1, a crank 118 which engages by a pin 120 in the end of a spring-loaded operating member 112. The latter has a shaft 106 which passes through a block 104 secured by a pin 102 to an end plate 74 secured to the non-movable portion 14. Thus as the segment 50 is moved outwardly the operating mechanism tends to maintain a fixed distance between pins 120 and 102 causing the gripper member 92 to rotate to grip the sheet material 98, any slight differences in material thickness being accommodated by the compression of spring 124. Another segment 50 may have a similar gripper mechanism which is orientated to grip material for winding in the opposite direction of rotation. The right-hand end of shaft portion 94 is fixed to a cam (130), Fig. 8 (not shown), whereby the gripper jaws can be levered free .should they become jammed on the sheet material.