GB1138931A - Apparatus for punching sheet material - Google Patents

Abstract

1,138,931. Cutting-out presses. INDUSTRIEWERKE KARLSRUHE A.G. 11 Jan., 1967 [2 March, 1966], No. 1538/67. Heading B4B. [Also in Division B3] In an apparatus for punching blanks the work material, which is drawn from a roll or is in lengths, is oscillated in the feed plane about an axis perpendicular to the feed plane, the axis of oscillation being spaced from the axis of the punching tool by four to ten times the width of the strip and is characterized in that interdigitated blanks are punched on a multi-stage press in one pass by two punching tools, each comprising a punch and a die, the tools being relatively angularly displaced by 180 degrees. The oscillating feeding and straightening device 4 is described in Specification 1,036,993 and feeds the strip 6 alternately to each of two punching stations A and B which include respectively dies 10 and 11. After a blank has been punched from the strip at one station the strip is fed forwardly and simultaneously swung to a position over the other die. Below the dies are a pair of rails 14 which carry grippers 15 and 16. The rails reciprocate longitudinally and also transversely so that punched blanks are forwarded step-by-step in the direction of the arrow 9. Under the die 11 are four resiliently biased sliders 17, one end of each of which projects under the die opening and the other ends of which have a downwardly turned lip, which is engaged by an upwardly turned lip 19 on each of four tongues 20. The tongues are attached to the rails 14 and move into engagement with the sliders 17 when the rails 14 are displaced one step to the right from the position shown in Fig. 2. Station C is an idle station and at station D there is a blank rotating device 21 which reciprocates vertically in synchronism with the punches which cooperate with the dies 10 and 11. Alternate blanks 8 reach Station D in the position shown in dotted outline and when in this position they obstruct the downward movement of a pin 22 which is resiliently mounted in the device 21. This causes rotation of the device to move the blank to the position 7 shown in solid outline. Operation.-A blank punched at Station A is carried by the grippers 15 to station B during the upward movement of the punches and deposited under the die 11. Simultaneously the strip is moved over the die 11. At the next stroke of the press a blank is pushed through the die 11 and is prevented from dropping on to the first blank by the sliders 17. As the punches retract the grippers 16 close on to the first blank and move it to station C. This brings the tongues 20 in alignment with the sliders 17 so that as the grippers move apart to deposit the first blank at station C, the second blank is released at station B.