Gas regulator with adjustable safety device
BACKGROUND OF THE INVENTION 
     This invention concerns a gas regulator with an adjustable safety device, which is connected between a gas tank and a gas stove or burner, possible to automatically regulate gas pressure at a stabilized value and also cut off gas supply in case of gas leakage. 
     SUMMARY OF THE INVENTION 
     This invention has been devised to have the following features. 
     1. It has two pressure regulators to regulate the pressure in a chamber in a main body at a stabilized value to be supplied to a gas stove or burner so that two diaphragms in the pressure regulators may have a longer service life and gas volume going out can be kept steady and gas filling time can be comparatively short. 
     2. It can automatically cut off gas supply in case of gas leakage. 
     3. A steel ball in a micro adjusting unit included in it can be adjusted in its sensitivity for blocking up gas passage to acquire controlling function for safe gas flowing volume. 
     The gas regulator with an adjustable safety device in the present invention comprises a body, two pressure regulators, two valve caps, a recovery unit and a micro adjusting unit combined together. 
     The two regulators combined on and under a pressure regutating base have two diaphragms and two pressure regulating plates. The diaphragms and the plates can swell up and shrink down together in accordance with the gas pressure in a chamber in the body. When the gas pressure becomes comparatively large, the diaphragms and the plates swell up to close up temporarily a gas hole communicating with a gas inlet hole and shrink down to leave off the gas hole if the gas pressure becomes less so that the gas pressure in the chamber can be regulated at a stabilized value. The micro adjusting unit has a steel ball placed in a tube, and the ball can be pushed by a large gas pressure to block up an end opening of the tube to cut off gas supply in case of an irregular occasion such as gas leakage, to acquire automatic safety measure. 
     The recovery unit has a turning button, which can be manually screwed to make a stem in the recovery unit move inward to push the steel ball off the end opening in the tube to recover the usual gas supply in case of the steel ball automatically cutting off gas supply and screwing the turning button can retreat the stem back outward. The sensitivity of the steel ball against the gas pressure can be adjusted by changing the distance between the steel ball and the end opening of the tube by means of the micro adjusting unit, so as to acquire the best possible safety to cope with gas leakage. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     FIG. 1 is an exploded perspective view of the gas regulator with an adjustable safety device in the present invention. 
     FIG. 2 is a cross-sectional view of the gas regulator with an adjustable safety device in the present invention, which is in assembled condition, with two pressure regulators being under abnormal pressure and with two regulating plates extending outward. 
     FIG. 3 is a cross-sectional view of the gas regulator with an adjustable safety device in the present invention, which is in assembled condition, with the pressure regulators being under normal pressure and with the regulating plates in flat condition. 
     FIG. 4 is a cross-sectional view of a steel ball pressed forward to close up an end opening in a round tube in a micro adjusting unit in the gas regulator with an adjustable safety device in the present invention in case of gas leakage. 
     FIG. 5 is an actional cross-sectional view of a recovery unit in the gas regulator with an adjustable safety device in the present invention. 
     FIG. 6 is an actional cross-sectional view of a micro adjusting unit in the gas regulator with an adjustable safety device in the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in FIGS. 1 and 2, the gas regulator with an adjustable safety device comprises a main body 1, an inlet tube 11 and an outlet tube 13 oppositely and integrally attached to the main body 1. A chamber 10 is provided in the main body 1, extending vertically with its top and bottom open, and a pressure regulating base 14 is placed in the chamber 10 near the inlet tube 11. The pressure regulating base 14 has several threaded holes 140 in the top and the bottom, a pin groove 141 behind each hole 140, a gas hole 142 behind the pin groove 141 communicating with the inlet hole. The main body 1 also has two opposite nut holes 15, 16 in the right (rear) portion, and the nut hole 15 continues to be formed with a two-stage stem hole 17. 
     Two pressure regulators 2, 3 are respectively provided on and under the regulating base 14, consisting of two round diaphrams 21, 31, two regulating plates 20, 30, and two coil springs 22, 32. The regulating plates 20, 30 are flat and rectangular, having two round downward projections 200, 300 near their left end, two pairs of engaging projections 201, 202, 301, 302 near the projections 200, 300. Two pairs of pins 203, 204, 303, 304 are fixed sidewise on the engaging projections 201, 202, 301, 302 and stoppers 205, 305 adhered on the projections 200, 300. Two pulling blocks 210, 310 are provided to connect with the regulating plates 20, 30, having connecting holes 211, 311 for one ends of the plates 20, 30 to engage therein. The diaphragms 21, 31 have projecting cones 212, 312 at the center of the upper surface and two caps 4, 5 are provided to cover and be screwed on and under the body 1, having a conical cap posts 40, 50 bored with threaded holes 400, 500 for bolts 41, 51 to screw with. The cap posts 40, 50 are also bored with spring holes 42, 52 for the springs 22, 32 to fit therein. 
     A recovery unit 16 is provided in the front portion of the body 1, consisting of a turning button 60, a nut 61, a stem 62 and a coil spring 63. The turning button 60 has an inner cavity 600 for mounting the nut 61 therein, and through holes 601, 610 are provided in the button 60 and the nut 61 for the stem 62 to extend therein. The stem 62 has a stop ridge 620 at the intermediate portion, several anti-leak packing rings 621 around a front threaded portion 622 and a coil spring 63 being sleeved around the rear portion. 
     A micro adjusting unit 7 is provided in the rear portion of the body 1, consisting of an anti-leak packing ring 70, a tube 71, a steel ball 72, a stem 73, a nut 74 and a micro adjusting button 75. The anti-leak packing ring 70, the tube 71 and the steel ball 72 are in order mounted between a nut hole 16 and a stem hole 17 provided in the rear portion of the body 1. The tube 71 has a number of air holes 710. The micro adjusting button 75 has an inner cavity 750 for the nut 74 to fit in, and a central through hole 751 to communicate with a central through hole 740 in the nut 74. The stem 73 is mounted in the through holes 740 and 751, projecting in the tube 71, and having the conical front end 730, several anti-leak packing rings 731 around the rear threaded portion 733 and a stop ridge 732 at the beginning of the threaded protion 733. The nut 74 screws with the nut hole 16. 
     After this gas regulator has been wholly assembled for use, and if the gas in a gas tank flowing through the connecting tube 11, a gas hole 142 and into the chamber 10 is in high pressure condition or flows out in a large volume, the chamber 10 can be filled up with flowing gas, forcing the regulating plates 20, 30 to move outward and thus the diaphrams 21, 31 also to swell outward compressing the springs 22, 32, as shown in FIG. 2. When the regulating plates 20, 30 have moved to become horizontal, the stoppers 205, 305 can close up the gas hole 142 as shown in FIG. 3 so that the pressure within the chamber 10 may be kept at a stabilized value. After the gas in the chamber 10 has flown out, the springs 22, 32 so far compressed will recover elasticity to push back the disphragms 21, 31 and the regulating plates 20, 30, forcing the stoppers 205, 305 to separate from the gas hole 142 as shown in FIG. 2. Then the chamber 10 can be refilled with gas swiftly, and the steel ball can be prevented from blocking up the tube 71 to cut off gas flow completely caused by large pressure difference. And the diaphragms 21, 31 can have longer service life. 
     In case the gas stove or burner connected with the outlet tube 13 should have broken or gotten out of order, flowing speed of gas at the leaking side (or the connecting tube 13) will become faster than the inlet side (or the connecting tube 11), and the pressure in the chamber 10 will become bigger than the leaking side, breaking the original pressure balance and giving rise to a pressure difference. Then the steel ball 72 in the tube 71 can be pushed to and block up the front end opening of the tube 71, automatically cut off gas supply, to resultant safety. 
     After the gas supply has been cut off by the steel ball 72, it can be restored by screwing rearward the turning button 60 in the recovery unit 6 to retreat rearward the stem 62 so as to push the steel ball 72 to leave off the front end opening of the tube 71 as shown in FIG. 5. Then gas can be supplied again as usual, and the turning button 60 can be screwed back outward to pull the stem 62 out of the tube 71. 
     The micro adjusting unit 7 is used to adjust the sensitivity of the steel ball 72 to acquire the best possible safety to cut off gas supply in case of gas leakage. The adjusting button 75 is screwed inward and outward, moving inward and outward the stem 73, which then pushes the steel ball 72 to adjust the distance between the ball 72 and the end opening of the tube 71. If the distance between them is adjusted short, the ball 72 can be absorbed to block up the end opening of the tube 71 even if the pressure in the chamber 10 is small as shown in FIG. 6. But if the distance between them is adjusted long, the ball 72 needs to be pushed to block up the end opening of the tube 71 by a larger pressure in the chamber 10.