CUTTER CHAIN WITH STAGGERED ROTARY BITS

• US 3,841,707 A
• Filed: 03/19/1973
• Issued: 10/15/1974
• Est. Priority Date: 04/01/1971
• Status: Expired due to Term

• Current Assignee: Donald L. Leibee, Thomas J. Kniff
• Original Assignee: Donald L. Leibee, Thomas J. Kniff
• Inventors: Kniff, Thomas J., Leibee, Donald L.
• Primary Examiner(s): Crowder, Clifford D.
• Application Number:
  US05/342,533
• Time in Patent Office: 575 Days
• Field of Search: 37/142,191,192 299/82,83,86,84
• US Class Current: 299/84.1
• CPC Class Codes: E21C 35/18 Mining picks; Holders therefor planing knives E21C27/44

Abstract

A cutter chain, especially for the excavation of formations, in which the chain is made up of links pivotally interconnected in end to end relation with blocks mounted on the links and inclined at relative angles in opposite directions relative thereto and carries a pick type bit having a point end inclined forwardly in the direction of movement of the chain. Advantageously, each bit is rotatably mounted in a sleeve which, in turn, is rotatably mounted in a respective block.

Claims

1. A cutter chain, especially for excavating operations comprising:

a plurality of links pivoted together in end to end relation to form an endless chain adapted for being supported and driven in the direction of the length of the chain with both reaches of the chain in a single plane, a block fixed to each said link and projecting outwardly therefrom in the general direction of said plane, bores in said blocks, pick type bits each symmetrical about a respective longitudinal axis and each having a rearward shank portion which is round in cross section and a front portion which tapers inwardly to a point at the front end of said bit, a sleeve rotatable in the bore in each block and each bit having the shank portion thereof rotatably mounted in a respective sleeve, each sleeve and block and each bit and sleeve comprising interengaging elements of abutment means for sustaining axial thrusts imposed on the bits in operation, said blocks supporting said sleeves and bits with the longitudinal axes of the bits diverging from said chain in the forward direction when said chain is viewed from the side, each block having a planar bottom surface engaging the respective link of the chain, each said bottom surface being disposed at a respective angle with respect to a central axial plane of the block when viewed longitudinally of the chain for supporting the blocks on the chain so that some of said blocks are tilted on said chain in respective directions lateral to said plane when said chain is viewed in lateral cross section, at least said some of said blocks being positioned on the chain with the longitudinal axes thereof disposed at an angle to the said plane in which the reaches of the chain are disposed when the chain is viewed from above so the longitudinal axes of the respective bits therein diverge from said plane in respective directions in the forward direction and at respective angles, the said tilting of said blocks on said chain and the said angular positioning of the said longitudinal axes thereof relative to said plane disposing the point ends of the bits therein in laterally distributed relation with respect to the said plane in which the reaches of the chain are disposed, said blocks and bits being arranged in successive groups along said chain, an adjacent pair of groups forming a sequence, the leading group of blocks and bits in a sequence including a leading block whic presents the bit therein with the longitudinal axis in said plane, the other blocks of said groups presenting the bits carried thereby at respective angles of inclination to said plane so the point ends of the bits are disposed alternately on opposite sides of said plane, each group terminating at the trailing end in blocks disposed to support the bits therein with the point ends at the extreme side edges of the path spanned by the point ends of the bits of the sequence, the angle at which the axis of each bit following said leading bit diverges from said plane in the forward direction when viewed from above the chain increasing from front to back in each said group, the point ends of the bits of said groups being so disposed that when a sequence of bits is viewed in the direction of movement of the chain, the point end of each bit of the trailing group of the sequence other than the terminal bits thereof is disposed about midway between adjacent point ends of bits of the leading group of the sequence.

2. A cutter chain according to claim 1 in which the point ends of the bits viewed in the direction of the length of the chain are disposed substantially on a circular arc.