Coal plane with chain operated turning head

Abstract

A coal plane for use against a coal face, comprises a plane body which has a plane guide. A plane chain is arranged in the plane guide and has chain ends engaged on respective sides of the plane body. A bit support is mounted in the plane body for pivotal movement about a vertical axis in a working direction toward the coal face. A horizontal control shaft, mounted orthogonally to the longitudinal direction of the plane chain on the plane body, is provided, to actuate the bit support. A turning head is mounted on a control shaft for rotation therewith and it operates between two spaced apart slide plates. A lever arm is secured to the control shaft for rotation therewith and a control chain mounted for reciprocating motion is engaged with the lever arm and is connected to the ends of the plane chain. The control chain acts on the plane body with a clearance of motion in order to transform a reciprocating movement of the control chain in dependence on the pulling direction of the plane chain during pivoting of the turning head on the control shaft into a pivotal movement of the bit support about its vertical axis in a working direction toward the coal face.

Dependencies are inferred from the claim text.