Patent GB-1044365-A (GB)
Title: Improvements in or relating to the cutting-machining of tubing
Inventor: MARSHALL WALTER
IPC: B23D45/12
Filed: 1963-04-02
Abstract: 1,044,365. Grinding; milling. SPEEDEX (ENGINEERING) Ltd. June 23, 1964 [April 2, 1963]. No. 12924/63. Headings B3D and B3K. [Also in Division B5] Apparatus for cutting and machining tubing 6 comprises at least one rotary groove cutting means 2 and at least one rotary saw 22, carrier means 5 for mounting the cutting means and saw externally of the tubing 6, means for causing relative rotation between the carrier means and tubing to produce at least one groove in the periphery of the tubing, and means for causing the saw to cut off at least one length of tubing. In the embodiment shown, the groove cutting means and the saw, which may be a rotary cutting blade or abrasive disc, are each mounted on the end of an arm 1a connected by a pin 12 to a further arm 1 mounted on a pivot 3 secured to a ring 5 which is mounted and operated by means such as described in Specifications 970,752 and 907,969 to give a planetary motion to the cutter and saw about the axis of the tubing 6. Each arm 1 is secured to an operating lever 8 connected at its end to an air motor 10 to rock the arm about the pivot 3; alternatively, cam means may be provided for rocking the arm. The cutter 2 is mounted on a spindle 11 at the end of the arm 1a, the spindle being connected by a belt drive to a motor 16 carried by the arm 1a. The depth of cut of the cutter is controlled by a wheel 14 which engages the surface of the tubing or a cam profile and is mounted on an. eccentric quill rotatable to vary the depth of cut of the cutter 2. The arm 1 can be adjusted to suit the size of tubing by a worm 18 which is carried by the lever 8 and meshes with a toothed segment 19 on the arm. The arm 1a carrying the spindle 11 for the groove cutter 2 is loaded by an adjustable compression spring 15 for setting the contact pressure between the wheel 14 and tubing 6. The arm 1a carrying the spindle 11a for the saw 22 is not spring loaded and is connected by a fixed joint to the arm 1. In operation, the cutter 2 is moved through 360 degrees or more to cut the annular groove in the tubing and the saw blade 22 is then used by rotating the ring 5 in the same or reverse direction to cut through the tube. More than two arrangements 1, 1a may be mounted on the ring for operating on large diameter tubing, or one or more arrangements of arms 1, 1a may be used each having a saw mounted between a divided milling cutter for chamfering the two ends of the tubing as it is being sawn. A single chamfer may be formed by a cutter mounted on one side of the saw. For badly distorted tubes, a wheel 14 may be mounted each side of a cutter, and the arms 1, 1a be free to pivot about a line tangential to the contact point between the tubing and a point midway between the wheels. Instead of wheels 14, a V-block free to pivot about the spindle 11 may be used, and angle of the V may be adjustable to compensate for wear of the cutter. Scrapers and/or air jets or brushing means may be provided to prevent swarf interfering with the wheels 14. In another embodiment, the arm 1a is double-ended with the saw at one end and the cutter at the other, the saw and cutter being driven by a single motor and an air cylinder or cam is used to rock the arm to present either the cutter or saw to the tubing. In further embodiments, the saw is given a reciprocatory movement, the tubing may be rotated instead of the carrier ring 5, and the cutter may be angularly adjustable on the arm to vary the angle of the groove. The apparatus is mounted on travelling means for cutting the tubing as it moves linearly and returns to its starting position after each cutting operation.