Patent GB-1444902-A (GB)
Title: Apparatus for bending wire
IPC: B21F1/00
Filed: 1972-05-13
Abstract: 1444902 Bending wire; feeding wire; shearing INTALOK Ltd 2 Aug 1973 [13 May 1972] 22590/72 Headings B3E and B3W Apparatus for bending wire 26 comprises a bending station, a feeding device 45 for feeding wire through the bending station, a bending device to bend wire projecting from the station about an abutment 16 at the station, a device to sequence the operation of the feeding device and bending device to produce a required wire component, a fixed guide 15 at the bending station having a bore through which the wire is fed, one end of the guide constituting the abutment, and the bending device comprising a plurality of fluid actuated rams 17, Fig. 6, each having a reciprocable piston-rod and a bending head 22 and mounted so that they can take up any relative angular position about the abutment. The rams are pneumatic and mounted by brackets 18 on an annular face plate coaxial with the guide. Grooves of semicircular crosssection are provided in faces 27, 28 of the head 22 to receive the wire and a stop 31, 32 is provided for limiting the travel of the head towards the guide. For the production of more than one angle of bend the adjustable stop 31, 32 is replaced by a variable stop unit comprising an indexing disc (34) carrying screw stops (35) Figs. 10, 11 (not shown). A wire straightening device (44), Figs. 1, 2, 4B (not shown), is provided ahead of the feeding device 45 which includes internal jaws 49, Fig. 5A, for gripping the wire 26 and is mounted on a reciprocating carriage (48), Fig. 7 (not shown), slidable along sliders 50, Fig. 4A, and driven by a pneumatic piston and cylinder unit 51, Fig. 5B. A cylindrical drum 56 is utilized to vary the stroke of the piston of unit 51 so that different lengths of wire can be fed through the guide 15 between successive bending operations. The drum is provided with a plurality of radially projecting adjustable stops 57 and the carriage (48) is provided with an abtument (58) for engagement with the stops. The drum is indexed by a pneumatic unit 66 whose piston-rod is pivotally connected to a crank arm (67) keyed to a clutch spindle 62. A clutch plate 69 is keyed to the spindle and is spring loaded to bear against a friction plate 70 with a one-way spring clutch 71 acting between the plate 70 and spindle 62. Movement of crank arm (67) rotates spindle 62 and then drum 56 through sprag clutch 71. On return movement of the piston the drum starts to rotate backwards through operation of the clutch 61 and is stopped by engagement between pin 65 and pawl 64. The wire may be guillotined using a die 79 slidable through a slot in the bore of the guide 15 via a guide channel 82. A steel insert 81 on the die co-operates with a steel insert 80 on the tip of the guide for shearing the wire. The die 79 is pivotally connected to a lever 83 in turn pivoted to a piston-rod of a unit (84). Sequencing of the apparatus is effected by using low pressure air jets to detect movements of the piston rods and cause closing of respective jets when a moving part reaches its end of travel to subsequently generate a signal which is then amplified. Gaskets with particular hole patterns corresponding to which low pressure air lines are to be closed are placed between the jets and a rotating distributor adjacent the amplifier.