METHOD AND DEVICE FOR MAKING CORE RECEIVER Russian patent published in 1994 - IPC

FIELD: drilling engineering. SUBSTANCE: device has cylinder 1 whose outer side is provided with grooves 2 made of dielectric material 3. Strips (wire, belt) are set in groove 2 and cylinder is inserted in core receiver 7. Voltage is then applied to contact 6. In so doing, plungers 5 are set in operation, projected out, press strips 2 to core receiver 7, and they are welded. When the voltage is cut off plungers 5 moves back under the action of springs and cylinder 1 is extracted from core receiver 7. If grooves 2 are wound cylinder 1 is extracted with rotation. Central passage 8 and radial passages are used for supplying power to contacts 6 for filling with fluid that creates pressure on plunger 5. EFFECT: simplified method and device. 5 cl, 3 dwg