ELECTROMAGNETIC HAMMER Russian patent published in 1995 - IPC

FIELD: mining industry. SUBSTANCE: electromagnetic hammer has four similar in size electromagnetic coils 1-4 enclosed in separate circular ferromagnetic bodies 5-8 with ferromagnetic poles 9 and 10 and diamagnetic flanges 11-16. In this case, electromagnetic coils 1-4 and poles are centered by diamagnetic guide 17 with striker 18 moving inside guide 17 to hit head 19 and working tool 20. Each electromagnetic coil 1-4 is connected to its power supply unit 21-24. Located between head 19 and lower electromagnetic coil are position pickups 41-43 connected to matching unit 44. Pickups 41-43 send signals on position of striker 18 and matching unit 44 forms signals based on this information for control of operation of power supply units 21-24. Matching unit 44 employs logic elements and has NOR circuits 45 and 46, univibrators 59 and 50 with potentiometers 51 and 52, pulse delay element 53 of pickup 42, AND circuits 54 and 55, RS-flip-flops 56 and 57, and START and STOP buttons 47 and 48, respectively. Energizing of electromagnetic coils 1-4 for motion of striker 18 takes from the first electromagnetic coil 1 to the third electromagnetic coil, or from the second electromagnetic coil 2 to the fourth electromagnetic coil at the moment when upper end face of striker 18 does not reach the point of separation of the second and third or the third and fourth electromagnetic coils. Such switching promotes improvement of the process of transformation of energy of switched off coil into switched on one. EFFECT: higher efficiency of hammer due to control optimization. 3 dwg