Patent GB-545810-A (GB)
Title: Improvements in or relating to rod or pipe bending machines
IPC: B21D7/024
Filed: 1940-12-10
Abstract: 545,810. Angular bending. PARKER, A. LA R. Dec. 10, 1940, No. 17493. Convention date, Jan. 16, 1940. [Class 83 (iv)] In a rod or pipe bending machine of the kind in which the pipe &c. is clamped to either side of a radius block rotatable in either direction to impart either right or left hand bends to the pipe &c. means are provided movable with the pipes &c. and opposed to the radius block for engaging the pipe &c. at the immediate point of bend for maintaining the pipe &c. in contact with the radius block. The peripherally grooved radius block 58 is mounted on pins 24, 23 on a disc 21 which is carried by a spindle 14 and is rotated in bearings 13, 12 respectively in a housing 5 and in a base plate 10. The clamp, which is carried by a bar 47 pivatally mounted at 48 on the pin 24, consists of a replaceable grooved rectangular block 52 resting on the base 51 of a slide 49 which is adjusted along the bar on guides by a screw 54. The abutment, which is carried by a bar 27 pivotally mounted on the spindle 14, consists of a replaceable grooved rectangular block 45 similar to the block 52 and resting either on the projecting end of a plate 42 secured to a block 40 carried by a longitudinally adjustable plunger 35 when bending large pipes or resting on pins 44 projecting from the block 40 when bending small pipes &c. The plunger 35 is adjusted by a hand operated screw 38 in a block 32 having guide ears 33 straddling one of the portions 28 or 29 of the bar 27. The block 32 is adjustable along the bar and is fixed in position by a pin 31 passing through one of the apertures 30 therein. During bending the block 45 slides over the pins 44 and against the surface of the block 40 so as to avoid abrasion of the pipe &c. When bending by rotating the block 58 in a counterclockwise direction the arms 47, 27 are critically positioned as shown in Fig. 2 with the block 32 mounted on the limb 28 of the arm 27. When bending by rotating in a clockwise direction the arms are swung round into the dotted position shown in Fig. 2 and the radius block is reversed on the pins 24, 23 as shown dotted. For large pipes a radius block may be provided having radial recesses 67, Fig. 12, at both sides to engage removable radial driving lugs projecting upwardly from the sleeve 21. During operation the arm 27 is held against the stop walls 8 of a concentric deck portion 7 of the housing 5. Wrinkling of the pipes is prevented by providing a mandrel 72 carried by a rod 73 secured to a threaded anchor rod 75, this rod is adjustable in a cross slot 76 in a standard, which is graduated from the centre point in alignment with the axis of the disc 21 so as to position the mandrel tangentially with respect to the radius block according to the diameter of block and pipe and direction of bending. The spindle 14 carries a gear wheel 15 which is driven by a pinion 112 on a spindle 110 provided also with a gear wheel 121 which may be driven by a ratchet lever 124 directly clutched thereto for small pipes &c. or through pinions 123 on shafts 122 on which similar clutch levers 124 are mounted when bending larger pipes &c. The levers on shafts 122 may be operated separately or collectively. The levers are provided with ratchet toothed plugs 126 which are longitudinally slotted to engage pins 134 and are normally pressed forward by springs 135 but can be retracted by pulling back forked members 136 in order that the plugs may be rotated to position them in a seated postion or in a forward or backward driving position. The gear wheel 15 is provided on its underside with a heartshaped cam 16 which operates a slide 18 engaging a stop 80 to limit the angle of bend. The stop 80 is carried by a screw 81 which is adjusted by a screwed sleeve 82 operated by a handle 85. The screwed sleeve carries an adjustable abutment member 87 between which and a bearing 89 is mounted a spring 88 so that during bending the slide 18 after coming into contact with the stop 80 moves back the stop and sleeve 82 until the abutment engages bearing 89. The movement of the hand wheel 85 thus' produced can be observed by the operator and forms a visual indication of the desired angle of bend. This angle can be shown when setting the stop 80 by providing a worm portion on the sleeve meshing with a worm wheel 90 on a shaft 91 carrying a graduated dial 93. The termination of the bending operation may also be effected by the abutment 87 engaging a trip lever so as to remove a detent from a recess in a pivoted spring-pressed bail 95 which thus rises so that notches 99 or 101 in its upper surface engage lugs 141 on the ratchet levers 124 to lock them in position. In order that the progress of the bending operation may be observed the spindle 110 is provided at one end with a small pinion 113 engaging a gear 118 carrying a graduated dial 117 rotating under a sight window 116 in a closure plate 115. Specification 545,831 is referred to.