GB737880A - Improvements in or relating to tool carrying chains for use on mining cutters for coal and like minerals - Google Patents

Abstract

737,880. Chains. PROCTOR, S. E., and HOY & CO., Ltd., A. June 30, 1953 [April 21, 1952; July 4, 1952], Nos. 10033/52 and 16912/52. Class 24. A coal cutter chain of the type in which the joints between the links are ball-and-socket joints comprises means for adjusting the pitch of the chain by altering the spacing between the ball members thereof. In the chain shown, which is of the type described in Specification 626,080, the ball 18 of each ball-and-socket joint is eccentrically mounted on a shaft 17 adjustably supported in a chain link 11 so that rotation of the shaft with respect to the link results in variation of the pitch of the chain. The shaft 17 is locked in position by a pin 20 engaging one of a number of slots 19 cut in the face of the link block 15. Alternatively, the square 21 on the top of the stem 17 may be made longer and the upper portion of the bore in the block 15 constructed with a cross-section in the form of an eightpointed star. The square 21 engages the points of the star which provides positions of adjustment at angles of 45 degrees to one another. As further alternatives, the eccentric stem 17 may be located eccentrically in a surrounding bush of square cross-section mounted adjustably in the block 15, or the ball 18 may be made concentric with its stem 17 which passes at an angle through a bush mounted in the block 15, or a liner may be provided which is bored out so that the socket portion in the interior is eccentric to the exterior and the pitch can be adjusted by rotating the liner in its bore or by replacing the liner with another liner of different eccentricity. In the type of chain described in Specifications 699,636 or 715,776, in which the ball-stem extends from the socket directly towards the neighbouring link, the ball is made adjustable relative to the stem by means of a screwed joint.