Patent GB-801374-A (GB)
Title: Improvements in or relating to methods of and machines adapted for use in turning wood heel blanks
IPC: B27M3/20
Filed: 1956-02-02
Abstract: 801,374. Shaping wood by cutting. BRITISH UNITED SHOE MACHINERY CO., Ltd. Feb. 2, 1956 [Feb. 9, 1955], No. 3299/56. Class 145. A wooden heel blank 34 supported on a jack 36 is shaped in a single operation by a continuously-rotating cutter 26 and the rate of relative movement of the blank and cutter is controlled so that it can be slowed down while the cutter is operating on parts of the blank where the direction of the grain of the wood is liable to cause chipping. A motor 168 continuously drives a small pulley 158 and large pulley 160 and one or other pulley can be connected to a shaft 156 by two interacting clutches 162, 162a controlled by an arm 192. The shaft 156 is connected through a one-way clutch 130 to a drive shaft 70 geared to a cam shaft 62 and rotating the jack 36 through a universallycoupled drive 72, 76, 82, 92. The jack is rotatable in a tiltable bracket 86 carried by a frame 60 which slides on rods 54 and is loaded by springs 102 to bring the blank into contact with the cutter. Cams on the shaft 62 control the various movements of the machine and include cams 64, 66 for controlling, respectively, the sliding movement of the frame 60 and the tilting of the jack and also a master cam 131 mounted for restricted angular movement on the shaft 62 within the limits imposed by a slot 141 and lug 139, the cam 131 being initially moved relative to the cam shaft by a ratchet mechanism 159 operated by a compressed-air motor 161 controlled by an automatic or manual valve 163. When a blank 34 has been on the jack, the ratchet mechanism 159 is operated to move the cam 131 relative to the stationary cam shaft until the lug 139 meets the end of the slot 141. A cam surface 122 has then caused compressed air to be supplied to a cylinder 120 operating a clamp 113 for the blank and a cam surface 137 has operated a valve 149 to supply air to a cylinder 155 which engages the one-way clutch 130. The cam shaft 62 begins to rotate at its higher speed, the smaller pulley 158 being effective, and the blank is moved towards the cutter, under the control of cam 64, the jack is rotated and the jack bracket 86 is tilted under control of the cam 66. When the cutter nears the back of the heel, where the grain of the wood is generally lengthwise of the blank, a striker 220b on the shaft 62 closes a switch 208 and energizes a solenoid to control a fluid-powered motor 204 that disconnects the clutch 162 and engages the clutch 162a for the larger pulley 160. The drive speed is then reduced until a striker 220 closes a second switch 206 to energize another solenoid controlling the motor 204 so that it reverses the clutches. If the heel shape is such that there is a tendency for the wood to chip in the area at the end of the cutting operation, additional strikers 220c and 220a are provided to slow down and then increase the drive speed in that area. At the end of the cutting operation, the cam 122 releases the blank clamp 113 and a cam 173 engages a valve plunger 175 to cause a jet of air to eject the finished blank. Just before the jack arrives at a final dwell position, the cam 137 moves away from the plunger of the valve 149 with the result that the clutch 130 is disengaged. A spring-loaded stop arm 142 engages the clutch 130 to ensure that the jack stops in the dwell position ready to receive another blank. Specifications 530,401 [Group XXIV], 690,250 [Group XXVI] and U.S.A. Specification 2,488, 100 are referred to.