HYDRAULIC CONTROL VALVE OF MECHANIZED SHAFT SUPPORTS Russian patent published in 1994 - IPC

FIELD: mining equipment. SUBSTANCE: hydraulic control valve of mechanized shaft support has body 1 with pressure channel 2, discharge channel 3, and working channel 4 and bore accommodating stack of bushings 5,6 and 7 accommodating, in their turn, cylindrical slide valve 8 with spring 9, pusher 10 and combined resilient packing 11 mounted on slide valve 8. Positioned between stack of bushings 5 and 6 is combined packing 12 intended for separating working channel 4 and discharge channel 3, while packing 11 separates pressure channel 2 and working chamber 4. Sectional dismountable slide valve 8 consists of two parts 13 and 14. Each part is made in the form of guide cylinder with female or male shank. Part 13 of slide valve 8 is located in zone of working and discharge channels 4 and 3 respectively. Female shank of part 13 has threaded socket with recess in front of it and through radial hole at its end. End face of shank is provided with collar 17. Part 14 of slide valve 8 has male shank with mounting seat and threaded union on its end. Bore and hole available inside part 14 are designed respectively to accommodate spring 9 and to pass working fluid. End face of slide valve part 14 , in the place of its transition to shank, is shouldered. Groove made in front of threaded union receives retaining resilient ring 24. When parts 13 and 14 of slide valve 8 are assembled, end face of collar 17 of part 13, end face shoulder and mounting seat of part 14 form groove for placing resilient packing 11, which consists of protective screen and power elastomeric round-section ring. Protective screen is manufactured also of elastomeric material of higher rigidity as compared with the ring and tightly envelops location of part 14 of slide valve 8. Sealing of pressure channel is ensured also by combined packing 27. Immovable bushings 5, 6 and 7 are sealed by means of packing rings 28, 29, 30 and 31. EFFECT: improved reliability. 2 cl, 5 dwg