US2083734A

US2083734A - Air-shooting apparatus

Info

Publication number: US2083734A
Application number: US730829A
Authority: US
Inventors: Noble Warren
Original assignee: SAFETY MINING CO
Current assignee: SAFETY MINING Co
Priority date: 1934-06-15
Filing date: 1934-06-15
Publication date: 1937-06-15
Anticipated expiration: 1954-06-15

Description

June 15, 1937. w. NOBLE 2,083,734

AIR SHOOTING APPARATUS Filed June l5, 1934 .inve/nya? if Wwm 7105@ lll l' ,e6 ywa' www' f v an@ 25,means of the blasting cartridge.

Patented June 15, 1937 UNITED STATES PATENT OFFICE 2,083,734 AIR- SHOOTING APPARATUS pany, Chicago, Ill., a corporation of Illinois Application June 15, 1934, Serial No. 730,829

24 Claims.

'Ifhisinvention relates to blasting cartridges and more particularly to improvements in the pressure release control means for a blasting cartridge of the type wherein high pressure gas is 5 employed as a blasting medium.

An object of this invention is to provide an improved pressure release control means for a blasting cartridge. Another object is to provide an improved control means for a blasting cartridge of the type wherein a highly compressed -gas is employed as a blasting medium, so that when it is desired to eect release of the blasting charge the same may be readily and quickly eiected. A further object is to provide an improved control means for the valve mechanism of a blasting cartridge of the above character whereby when it is desired to eiect a blasting function, the valve mechanism may be quickly opened to effect release of the blasting pressure.

20 Yet another object is to provide an improved automatic vent means for a blasting cartridge of the high pressure gas type whereby venting is effected in an improved manner thereby to effect quick operation of the blasting pressure release These and other objects and advantages of the invention will, however, hereinafter more fully appear.

In the accompanying drawing there is shown for purposes of illustration one form which the invention may assume in practice.

In this drawing:-

Fig. 1 is a somewhat diagrammatic view showing the association of the improved control means with respect to the blasting cartridge.

35 Fig. 2 is an enlarged longitudinal sectional view taken through the illustrative form of the improved pressure release means and the associated blasting cartridge.

Fig. 3..:is a fragmentary .view of the control 40 means shown in Fig. 2, showing the valve means in its pressure releasing position.

Fig. 4 is a cross sectional view taken on line 4 4 of Fig. 3. Fig. 5 is a cross sectional view taken on line 5-5 of Fig. 2.

I tion the improved pressure release control means, generally designated I, is shown associated with ,a blasting cartridge generally .designated 2, the latter, in Fig. l, being shown in position in a blast hole 3, and held therein by usual tamping 4. This blasting cartridge is herein of the type wherein a high pressure gas is used as a blasting medium, and in this instance is similar in design to that 65 disclosed in my copending application Ser. No.

In this illustrative embodiment of the inven-l '730,828 filed June 15, 1934. As above mentioned this cartridge is receivable in the blast hole 3 in the coal face and high pressure gas, herein air under high pressure, is conducted thereto through a short tube or pig tail connection 5. The blast hole is tamped at 4 at the outer end of the cartridge so that when the blasting pressure is released at the inner end of the cartridge the latter will tend to stay in the hole, thereby to enable the compressed gas to act expansively on the rear of the mine wall to break down the latter. The blasting cartridge 2 comprises a cylindrical metallic casing or shell 8, having a chamber 9 for receiving a charge of gas compressed to a high pressure. The chamber 2 at the outer end of the shell is closed by a head I threaded within the outer end of the shell. As shown, formed in the inner end portion of the shell is a bore II alined with a pressure chamber 9 and communicable therewith through a large axial opening I2. The outer end of this bore Il is closed by a cap I3 threaded within the inner end of the shell. Slidably mounted within the bore II is a piston I4, having formed thereon an end seating valve I adapted to engage a conical valve seat I6 surrounding the opening I2 to cut off communication between the bore I I and the pressure chamber 9. This piston carries an outer cup packing I1, tightly engaging the walls of the bore II to prevent leakage of pressure from the bore II past the piston I4. Also carried by this piston is an inner cup packing I8 tightly engaging the exterior periphery of a tube I9. This tube is herein secured at 20 within the rear head I0 and extends centrally through the pressure chamber 9 and through the piston I4 into the bore II, the interior of this tube communicating with the bore I I at the inner side of the piston I4. Compressed gas is adapted to be conducted through this tube I9 through a passage 2l communicating with the short tube or pig tail connection 5. In this instance connecting the bore II with the exterior of the shell is a series of outwardly inclined pressure releasing passages 22. When compressed gas is supplied to the tube I9 from the connection 5 the conipressed gas ows into the bore I I at the inner side of the piston and through the piston past the cup packing I8 to the pressure chamber 9. When a predetermined blasting pressure is attained within the chamber 9, the supply of compressed gas through the connection 5 is cut 01T, and thereafter this connection is suitably vented to atmosphere so that the pressure in the tube I9 and within the bore II at the inner side of the piston is substantially reduced. Pressure from the chamber 9 is prevented from leaking past the piston by the cup packing i8, and the relatively high pressure in the chamber 9 overcomes the reduced pressure in the bore l l, thereby causing the piston I4 to move suddenly inwardly and as a result unseat the valve l 5 to release the blasting charge from the chamber 9 through the axial opening I2, past the valve and through the pressure release passages 22.

Now referring to the improved pressure release control means for eiecting rapid venting of the cartridge, it will be noted that in Figs. 2 and 3 there is shown a cylindrical casing 25 having a bore 26 closed at its upper end by a head 2l and at its lower end by a head 28. Reciprocable in the bore 26 is a piston 29 carrying a cup packing 30 to prevent leakage of compressed gas from above the piston to below the same. Interposed between the lower side of the piston and the lower head 28 is a coil spring 3l which normally urges the piston 29 to its uppermost position. The bore 26 at the lower side of the piston is vented to atmosphere through a small vent passage 32. Connected to the upper head 2l is a pipe connection 33, leading to any suitable source of compressed gas supply, and this connection communicates through a passage 3d with the bore 26 at the upper side of the piston 29. In this illustrative construction, the upper head 2l is formed with a chamber 35 with which the short tube or "pig tail 5 communicates, and this chamber is connected by a passage 36 with the bore 26 at the upper side of the piston 29. Also communicating with the chamber 35 is a vent passage 3l which may be larger in cross section than tlie cross sectional area of the supply line of the smallest portion of the latter as desired. Flow of compressed gas from the bore 26 through the passage 36 to the chamber 35 is controlled by a check valve 38 normally maintained in its seated position by a coil spring 39. Flow of gas from the chamber 35 to the vent passage 3l is controlled by an end seating valve 60 engageable with a conical seat El surrounding the vent passage 3'1.' The valve 40 is herein inthe form of plunger 42 guided in a bore 63 formed centrally in the head 2l, and the inner end of this plunger projects inwardly within the bore 26 and is exteriorly grooved at 46. The head 21 is transversely slotted at 45, and swingably mounted in this slot are levers 49 herein .in the form of trigger release means for the valve 40 and having projections engaging the groove M. These levers 46 are pivotally mounted on pins il carried by the head 2l, and engageable with these levers are actuating

levers

48, 48 suitably mounted on pins 49 carried by the piston 29, these levers being pivotally mounted in a transverse slot 50 formed in the piston. 'Ihe lower ends of these

levers

48, 48 are constantly urged away from each other by a coil spring 5i interposed therebetween, thereby to maintain the upper ends of these levers in operative engagement with the trigger levers d6.

In the operation of the improved pressure release control means it will be noted that when Ahigh pressure gas is supplied through the pipe connection 33 and passage 34 to the bore 26 at the upper side of the piston 29, the latter is moved downwardly against the tension of the spring 3| and, the levers 68 being movable therewith, causes the upper ends of the latter to move below a transverse plane including the centers of the pivot pins 41 and as a result the trigger levers d6 are quickly swung about their pivots with a snap action to move the valve i9 tightly against its seat lil. The compressed gas in the bore 26 ilows through passage 36, unseating the check valve 38, and flows through the short tube or pig tail 5 to the blasting cartridge shell. When the desired blasting pressure is attained Within the blasting cartridge shell the supply of compressed gas to the pipe connection 33 is cut oi and the latter is vented to atmosphere and as a result the pressure in the bore 29 at the upper end of the piston 29 is substantially reduced, the coil spring 3l then quickly moving the piston 29 into its uppermost position, thereby moving the upper ends of the snap action levers @Il to the opposite side of the transverse plane including the centers of the pins 97, and as a result the trigger levers 4S are quickly swung about their pivots to move the plunger 92 downward, thereby to unseat the valve fill and to open the chamber 35 to atmosphere through the vent passage 3l. When the parts are thus positioned the cartridge is vented to atmospherethrough the pig tail" connection 5, chamber 35 and vent passage 3l, thereby to eiect operation of the valve mechanism of the cartridge to release the blasting charge.

As a result of this invention it will be noted that an improved pressure release control means is provided for a blasting cartridge of the type wherein high pressure gas is employed as a blasting medium, so that is desired the cartridge may be quickly vented to atmosphere to effect sudden release of the blasting charge control means. It will further be noted that an improved vent control means is provided for controlling the a blasting cartridge of the compressed gas type whereby the blasting charge may be quickly released to effect actuation of the pressure release mechanism. Obviously a spring 9i may be provided of such strength that valve @il will be opened much sooner than valve i5 would move to open position, i. e. upon a smaller pressure drop, and a much faster rate of venting of chamber l l can be secured, even aside from the quicker valve action. These and other uses and advantages of the improved pressure release control means will be clearly apparent to those skilled in the art.

While there is in this application specifically described one form which the invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a material breaking apparatus a casing having a storage chamber and a control chamber to be charged with a gaseous medium stored at high pressure, means in the casing to suddenly release the charge to a point of use by the venting of the control chamber, and a pressure control device for effecting quick venting of such control chamber comprising a vent valve and snap action means for quickly opening said vent valve having pressure responsive controlling means.

2. In a material breaking apparatus a casing having a storage chamber and a control chamber to be charged with a gaseous medium stored at high pressure, means in the casing to suddenly release the charge to a point of use by the venting of the control chamber, and a pressure control device for effecting quick venting oi such when a blasting function r valve mechanism of :v

control chamber comprising a vent valve and ,a charge of vgaseous pressure in a casing andis released suddenly to a valve' comprising a cylinder having a bore, a piston reciprocable in said bore and a snap action,

lvalve-actuating means operated by said piston.

3. In a material breaking apparatus a casing having a storage chamber and acontrol chamber to be charged with gaseousmedium stored at high pressure, means in the casing to suddenly release the charge to a point of use by the venting of the control chamber, and aypressure control device for effecting quick venting of such control chamber comprising a vent valve and pressure actuated means for effecting sharp opposite movements of said valve.

4. In a material breaking apparatus a casing having a storage chamber and a control chamber to be charged with a gaseous medium stored at high pressure, means in the casing to suddenly release the charge to a point of use by the venting of the control chamber, and a pressure control device for'effecting quick venting ofsuch control chamber comprising a vent valve and pressure actuated means for sharply opening and closing said'valve comprising a piston-actuated, snap action, valve actuating means operated to close said valve by the charge of gaseous medium on its way to the casing.

5. In a material breaking/apparatus a casing having` a storage'chamber and a control chamber to be charged with a gaseous medium stored at high pressure, means in the casing to suddenly release the cha'rge to a point of use by the venting of the control chamber, and a pressure control device for effecting-quick venting of such contro-1 chamber comprising a .vent valve and pressure actuated means for sharply opening and closing said valve comprising a pressure chamber, a piston reoiprocable in said chamber and a snap action valve actuating means operated by said piston.'

6. In a material breaking apparatus in which a charge of gaseous medium is stored at high pressure in a casing and is released suddenly to a point of use bythe venting of a control chamberwhich is lled with high pressure gaseous medium while the casing is charged, a pressure control device for effecting quick venting of such control chamber comprising a vent valve and pressure actuated means for quickly opening or closing said valve comprising a pressure chamber, a piston reciprocable in said chamber, and a snap action' valve actuating means operated by'said piston, said snap action means comprising levers pivotally mounted on said piston. Y

'7. In a material breaking apparatus in which medium is stored at high l point of use by the venting of a control chamber which is lled with high pressure gaseous medium while the casing is charged, a pressure control device for' eiecting quick venting ofsuch control chamber comprising a vent valve and pressure actuated means for quickly opening or closing said valve comprising a pressure chamber, a piston reciprocable in said chamber, and a snap action valve actuating means operated by said piston, said snap action means comprising levers pivotally mounted on said piston and snap action levers actuated by said piston levers.

8. In a material breaking apparatus in which a charge of gaseous medium is stored at high pressure in a casing and is released suddenly to a point of use by the venting of -a control chamber which is lled with high pressure gaseous medium having a bore, a piston reciprocable in said bore,

means for supplying compressed gas to said bore at'one side of said piston, a check valve for controlling flow of gas from said bore to the cartridge, and snap-action controlled means actuated by said piston for venting the chamber to eiect charge release.

9. In a material breaking apparatus in which a charge of gaseous medium is stored at high pressure in a casing and is released suddenly to a point of use by the venting of a control chamber which is lled with high pressure gaseous medium while the casing control device for effecting quick venting of such control chamber comprising a vent valve and means embodying a snap-action for quickly opening said valve comprising a cylinder having a bore, a piston reciprocable in said bore, means for 4supplying compressed gas to said bore at one side of said piston, a check valve for controlling the flow of gas from said bore to the cartridge, and means actuated by said piston for venting the chamber to eiect charge release, said check is charged, a pressure valve closing automatically when said vent valve is opened.

10. In a material breaking apparatus a casing having a storage chamber and a control chamber to be charged with a gaseous medium stored at high pressure, means in the casing to sudden- -ly release the charge to a point of use by the venting of the control chamber, and a pressure control device for effecting quick venting of such control chamber comprising a vent valve and pressure responsive trigger mechanism for actuating said valve.

11. In a material breaking apparatus a casing having a storage chamber and a control chamber to be charged with a gaseous medium stored at high pressure, lmeans in the casing to suddenly release the charge to a point of use by the venting of the control chamber, and a pressure control device for eiecting quick venting of such control chamber comprising a vent valve and pressure responsive trigger mechanism for actuating said valve effective to cause sharp closing movement of said valve when gas is supplied to charge the casing.

12. In a material breaking apparatus a casing having a storage chamber and a control chamber to be charged with a gaseous medium stored at high pressure, means in the casing to suddenly release the charge to a point of use by the venting of the control chamber, and a pressure controldevice for eiecting quick venting of such control chamber comprising a vent valve and quick acting pressure control means embodying a snap-action for actuating s'aid valve, said means acting to close quickly said valve when compressed gas is supplied to the cartridge,and to open quickly said valve when the supply of compressed gas to the cartridge is cut ofi and the cartridge is vented.

13. The combination with a cartridge having provision for storing a charge of gas under a high pressure, a supply line therefor, and means for releasing the charge to a point of use upon a reduction of pressure in the supply line, of means between the ends of said supply line for providing a vent orice larger than the minimum cross sectional area of the supply line, upon pressure reduction in said supply line.

14. The combination with a cartridge having provision forstoring a charge of gas under a high pressure, a supply line therefor, and means for releasing the charge to a point of use upon a reduction of pressure in the supply line, of means between the ends of said supply line and adjacent to but spaced from said cartridge for venting the latter upon pressure reduction in said supply line.

15. In a material-breaking apparatus a casing having a storage chamber and a control chamber to be charged with a gaseous medium is stored at high pressure, means in the casing to suddenly release the charge to a point of use by the venting of the control chamber, and means for effecting quick venting of such control chamber including a venting valve, a pressure responsive element and operative connections between said valve and element providing for different rates of movement between them.

16. In a material-breaking apparatus a casing having a storage chamber and a control chamber to be charged with a gaseous medium stored at high pressure, means in the casing to suddenly release the charge to a point of use by the venting of the control chamber, a conduit alternatively pressure-filled and vented to atmosphere, and a control apparatus connecting said conduit with said'control chamber and providing a chamber-venting device, a pressure responsive element oppositely movable upon rise and fall of conduit pressure, and means operative while said pressure responsive element is moving at a slow rate for` effecting a rapid opening movement of said venting device.

17. In a material-breaking apparatus a casing having a storage chamber and a control chambcrv to be charged with a gaseous medium stored at high pressure, means in the casing to suddenly release the charge to a point of use by the venting of the control chamber, a conduit alternatively pressure filled and vented Vto atmosphere, and a control apparatus connecting said conduit with said control chamber and providing a chamberventing device, a pressure responsive element oppositely movable upon rise and fall of conduit pressure, and means operative while said pressure responsive clement is moving at a slow rate for effecting a rapid closing movement of said venting device.

18. In combination, a casing providing a storage space for a charge of gaseous medium at high pressure and a control space, a charge release valve for said storage space having controlling means governed by pressure conditions in said control space and held closed when high pressure prevails in said space and opened and held open during charge release upon rapid venting of said control space, and means for governing pressure conditions in said control space including means providing a chamber adjacent said casing and in continuous communication with the control space of the latter and having a plurality of stationary valve seats, a conduit selectively connectable to a source of supply or to exhaust communicating withr one of said seats, a check valve on said seat preventing back ow through said conduit, the other seat communieating with exhaust and having a valve cooperating therewith, and controlling means for said last mentioned valve responsive to pressure conditions in said conduit and operative with a snap action.

19. In a material breaking apparatus, a control device for effecting quick venting of a high pressure gaseous blasting medium supply line comprising a vent valve, and pressure actuated means for quickly opening or closing said valve comprising a pressure chamber, a piston reciprocable in said chamber, and a snap-action valve actuating means operated by said piston, said snap-action means comprising levers pivotally mounted on said piston.

20. In\a material breaking apparatus, a control device for eifecting quick venting of a high pressure gaseous blasting medium supply line comprising a vent valve, and pressure actuated means for quickly opening or closing said valve comprising a pressure chamber, a piston reciprocable in said chamber, and a snap-action valve actuating means operated by said piston, said snapaction means comprising levers pivotally mounted on said piston and additional levers actuated by said piston levers.

21. In a material breaking apparatus, a control device for eiecting quick venting of a high pressure gaseous blasting medium supply line comprising a vent valve, and means for quickly opening said valve comprising a cylinder having a bore, a piston reciprocable in said bore, means for supplying compressed gas to said bore at one side of said piston, a check valve for controlling flow of gas from said bore, and snap-action ccntrolled means actuated by said piston for venting the chamber.

22. In a material breaking apparatus, a control device for effecting quick venting of a high pressure gaseous blasting medium supply line comprising a vent valve, and means embodying a snap-action for quickly opening said valve comprising a cylinder having a bore, a piston reciprocable in said bore, means for supplying compressed gas to said bore at one side of said piston, a check valve .for controlling the ow of gas from said bore, and means actuated by said piston for venting the chamber, said check valve closing automatically when said vent valve is opened.

23. In a material breaking apparatus, a control device for eiecting quick venting of a high pressure gaseous blasting medium supply line comprising a vent valve, a pair of levers for effecting a snap-action opening or closing of said valve when said levers are moved bodily longitudinally of each other, and pressure responsive means for effecting said longitudinal movement.

24. In a material breaking apparatus, a control device for effecting quick venting of a high pressure gaseous blasting medium supply line comprising a vent valve, a pair of levers for effecting a snap-action opening or closing of said valve when said levers are moved longitudinally of each other, and a pressure responsive piston operatively connected to one of said levers for effecting said longitudinal movement.

WARREN NOBLE.