GB797910A - Improvements in and connected with tube bending machines - Google Patents

Abstract

797,910. Angular bending. CHAMBERLAIN INDUSTRIES, Ltd. Feb. 20, 1957 [Feb. 27, 1956], No. 6081/56. Class 83 (4). A machine for bending rods or tubes having a rotary forming die to which the work is secured and about which the work is bent upon actuation of the die by an hydraulic fluid actuator, has valve means which stops the rotation of the forming die when the work has been bent through a predetermined angle and means to indicate the angle of bend. A spindle 26 is adjusted about its axis, by a cap 33, until a pointer 36 therein indicates on a fixed scale 37 the angle to which the work is to be bent, the spindle 26, by virtue of a one-way helical clutch spring 39, turning relative to a coaxial hollow shaft 31. A lever 10 is then actuated to rock a crank 14 linked to the stem 7 of a spool-type valve 6 in the supply line from the hydraulic power source to driving means for the forming die. The forming die, with the work clamped thereto, then rotates to bend the work and through chain-and-sprocket means drives the shaft 31 and, through the helical spring 39, the spindle 26 at twice the speed of the die. Rotation continues until a member 23 projecting from the spindle 26 hits a rocking cam 19, of inverted T shape, to depress the valve spindle 7 and close the valve 6 to stop the bending. The member 23 could alternatively engage a switch contact to make or break the circuit of a relay or solenoid operating the valve. Similar levers 10 may operate the clamp which secures the leading end of the work to the forming die, a pressure die, a mandrel and a booster.