GB841206A - Improvements in or relating to machines for making stirrups for use in reinforced concrete constructions - Google Patents

Abstract

841,206. Angular bending; shearing. SOC. DES ANCIENS ETABLISSEMENTS VIDAL, J. B. Oct. 25, 1956 [Oct. 25, 1955; Oct. 11, 1956], No. 32626/56. Class 83 (4). A machine for forming stirrups for metal reinforcements in reinforced concrete comprises a first bending means for forming an 180 degrees bend at one end of a wire blank, a second bending means spaced from the first for forming an 180 degrees bend at the middle of the wire blank and to provide a return-bent portion extending past the first bending means, the first bending means being arranged also to bend the end of said return-bent portion through 180 degrees in register with the first 180 degrees bend. Wire f is drawn intermittently from a coil through straightening rolls 3 and 4 by peripherally - grooved continuously - rotated rollers 8<SP>2</SP> co-operating with similar rollers 9<SP>2</SP>, said rollers being urged together, against springs, into driving engagement with the wire by an adjustable rotating cam 19, on a driven shaft 10, operating through a lever. When the wire f is stationary a length is severed therefrom by a shear 26 actuated through a lever 27 by a cam 17 on the cam-shaft 10. The bending is then effected by means carried in casings 47, 48 adjustable along a rod 49 and a shaft 50. The shaft 50 is oscillated by half-toothed bevel means 51, 52 on the main shaft 10. A cam 68 on the shaft 50 operating through linkage means 64, 62, 61, 60 projects heads 601, around which the wire is to be bent, through plates 571, 57<SP>2</SP>. These plates, which carry bending pins 58, 58<SP>1</SP>, are fast with hollow shafts 57 rotated by rack- and pinion means 55 driven by the shaft 50 to bend, through 180 degrees at one end and at the middle, a wire f presented thereto and placed on the heads 60<SP>1</SP> by feed members 69 moved towards the plates by cam means 73 on the shafts 57. The shaft 50 then rotates in the reverse sense and the plates 57<SP>1</SP>, 57<SP>2</SP> are rotated in a direction opposite their previous rotation. This causes a pinion 56, which has a helical slot engaged by a stud on the shaft 57, to slide axially of the shaft 57, and, through a connection 58<SP>2</SP>, to project the pin 58 further through the plate 57<SP>1</SP>. This pin thus engages the bentover arm of the wire stirrup E to form the terminal loop thereof at the other end. A hook 65 is engaged by a cam 67<SP>1</SP> on the shaft 50 at the commencement of its rotation in the original direction to withdraw the heads 60<SP>1</SP> and allow the completed stirrup E to fall away.