GB519052A - Automatic cathead especially for use in well-drilling plant - Google Patents

Abstract

519,052. Winches. OWEN, F. M. Oct. 4, 1938, No. 28830. Convention date, April 15. [Class 78 (v)] [Also in Group XXI] In line - reciprocating means for making and breaking connections in drill stems &c. wherein the line is wound on a continuously-rotating rotor and is freed therefrom after a partial rotation, the rotor having a rigid abutment and the end of the line a solid coupling member, an 'annular housing surrounds the part of the rotor on which the line is wound, the annular space therein being such that when the coupling is freed from the' abutment it may return to its first position without interference. Figs. 2, 3 and 4. A rotor 4 is keyed to a driven shaft 1 and between its end walls 11, 12 has a bifurcated projection 8 with a radial front abutment 6 and an arcuate rear face; the rotor may be integral with, or fixed to, a spool 9. A housing 13, open at its lower side, is supported on the rotor and is held, with play, by a bracket 20 connected to the draw-works frame. A bifurcated member 31 is held between the walls' of the housing by a pin 36 and has an upper part 41 of wedge form. A jerk line 18. of resilient wire and preferably with a spring steel core, carries a knob 24 held between a spring pulled lever 29 and the end member 13. On depressing the free end of the lever the 'knob 24. is raised into the path of the abutment 6 and a pull is applied to the line 18, the knob 24 being disengaged from the abutment when it engages the wedge 41. Figs. 5, 6 and 11. The housing 63 is centrally divided and the non-resilient jerk line or chain 18 carries a coupler 58 working within radial slots 56 in rotatable annuli 53, the slots having inward projections 57, and the coupler having split spring rings 61 riding on the walls of the slots. In operation, a lever 66 moves the coupler radially inward into the path of the abutment 6, the spring rings 61 yielding to permit the coupler to pass the projections 57, and then expanding to hold the coupler until it is moved outward by engagement with wedges 75 integral with the housing. Shoulders 72 on the housing limit return movement of the jerk line. The rotor 4 may have more than one abutment 6. Fig. 13. The jerk line or chain 84 has a coupler 80 carrying a pivotal latch 85, a coil spring 88 tending to force the latch outwardly; in operation, a lever moves the latch into engagement with an abutment 87 on the rotor, a wedge surface 89 ultimately disengaging the latch.