Patent GB-543262-A (GB)
Title: Improved apparatus for de-twisting metal sections
IPC: B21D3/12
Filed: 1940-08-15
Abstract: 543,262. Roller tables. HEAD, WRIGHTSON & CO., Ltd., and LAKE, N. C. Aug. 15, 1940, No. 13061. [Class 83 (iv)] An apparatus for de-twisting metal sections having a variation in degree of twist along their length comprises a frame having two heads which are adapted to allow free passage of the section therethrough but to grip the section for detwisting one head having a rotatable gripper connectible to driving means and the other being free to move longitudinally with respect to the rotatable gripper to allow for variation in length during detwisting. The head A which is fixed in a 'frame comprising four members B symmetrically arranged about the de-twisting axis and disposed so as to give freedom of access to the section, is bored to receive a gripper E which is rotatable on ball bearing rollers N therein and is driven by a spur gear O, P.R. connected by a clutch T to a motor U through a gear reduction unit S. The gripping jaws F are faced with polished metal or fabric and are moved radially by wedges H provided with dovetail slides I. Some of the jaws may be adjusted positively by screws M to facilitate alignment of the gripping surfaces in the rotary E and non-rotary heads C and the remaining jaws are operated by fluid pressure in cylinders J. The jaws in the head C are similarly operated. Both heads are also provided with adjustable cylinders furnished with pistons carrying rollers and for supporting the part of the section between the heads when the jaws are released. The head C which is mounted on ball bearing wheels Z and provided with steadying rollers A<SP>1</SP> is free to move longitudinally during de-twisting and may also be positively traversed to deal with varying lengths of sections by a hand wheel A<SP>2</SP> operating through sprockets and a fixer chain or a rack and pinion, or by an electrically driven winch. The cylinders J in the head E are connected at apposite ends to a divided manifold A<SP>8</SP> which communicates by flexible pipes A<SP>7</SP>, A<SP>10</SP> with the divided hub of a drum A<SP>6</SP> on which the pipes are wound so as to allow the head E to rotate 180 degrees. To avoid damage to the pipes due to excessive angular movement of the head E limit switches A<SP>13</SP> are provided so as to stop the motor. The head is balanced by one or more weights A<SP>12</SP>. The hub of the drum is connected by pipes A<SP>4</SP>, A<SP>5</SP> to a four way valve A<SP>3</SP> which controls the clamping or releasing of the jaws. The air connections for operating the jaws of the head C are directly coupled to another four way valve. Entry and delivery conveyers C2, G<SP>1</SP> are provided the conveyer G<SP>1</SP> being vertically adjustable by a hand wheel G<SP>2</SP> and the conveyer C<SP>2</SP> being raised and lowered through bell crank levers C3 through pipes so as to raise the conveyer to allow the section to be pushed through the apparatus clear of the jaws and to lower it out of the way during de-twisting. The cylinders carrying the rollers Y are also coupled with the cylinders J so as to be raised when the conveyer C<SP>2</SP> is raised. The gripper E is provided with a pointer V moving over a scale W on the part D so as to indicate the amount of twist and de-twist. To effect the de-twisting operation a section is pushed towards the gripper E over the raised conveyer C<SP>2</SP> and the gripper E is operated by the motor U to bring the jaws F into line with the end of the section to be de-twisted. The operator continues to push the section along the conveyer and through the gripper E until a change in the degree of twist occurs. The valve A3 is then operated to clamp the jaws F in the gripper E and the gripper is again rotated by the motor U until the end of the section is in a position in which it will enter the jaws of the head C. Air valve A<SP>16</SP> on head C is then operated to grip the section at this end. The motor U is then operated to effect de-twisting until the pointer indicates a degree of anti-twist whereupon the clutch T is disengaged to allow the stored energy in the section to rotate the gripper until the section is in its natural position. If the pointer still indicates a twist the operation is repeated. The operator then reopens the jaws and the section is pushed farther through the heads over the raised conveyer C<SP>2</SP> and rollers Y and the process repeated until the whole of the section is free from twists. The section is finally delivered on to conveyer G<SP>1</SP>.