US2207205A - Blasting cartridge - Google Patents

Description

July 9, 1940. c. J. SANDOE BLASTING CARTRIDGE Filed May 4, 1936 Patented July 9, 1940 amazes 2,297,205 naas'rma mammals Giarence i. Sandoe, University City, Mo., as-

signor to Carrion Corporation, a corporation of Illinois Application May 4,1936, Serial No. 77,725

My invention relates to blasting cartridges, particularly cartridges for use in the mining of coal and employing carbon dioxide or compressed air as the blasting medium. The invention has as its principal object a blasting cartridge which will remain in the blasting recess.

The invention consists principally in the provision of an annular peripheral flange at or near .the end of the cartridge that is foremost in the blasting recess, this rib fitting closely in the blasting recess, whereby the force of the blast tends to push the cartridge further into the recess instead of forcing it backwards out of the recess as is now commonly the case. The invention further consists in the blasting cartridge and in the parts and combinations and arrangements of parts hereinafter described and claimed.

In the accompanyin drawing,

Fig. l is a side elevation of a blasting cartridge embodying my invention shown in place in the blasting recess of a bed of coal,

Fig. 2 is an' enlarged view of the front end portion of said cartridge;

' Fig. 3 is a sectional view onthe line 88 in 25 Fig. 2, I

' Fig. 4 is an elevation of the end portion of a modification of the invention,

Fig.. 5 is an elevation of the end portion of another modification, whose rib is provided with a sealing washer,

Fig. 6 is a sectional view on the line BB in Fig. 5,

Fig. 'l is anelevation oi the end portion of a cartridge having a modified sealing washer arrangement, and

Fig. 8 is a sectional view on the line 8-8 in Fig. .7. Y Y

The drawing shows an external view of a blasting cartridge, which may use any desired blasting medium, carbon dioxide and compressed air being two blasting mediums commonly employed. The nature of the blasting medium and the details of the method and mechanism for setting off the charge are immaterial and form no part of the present invention which is concerned with the holding in the blasting recess of any type of blasting cartridge, regardless of the blasting medium employed.

In Figs. 1-3 is illustrated a cartridge I of con- '50 ventional type arranged in a blasting recess 2 in a coal body 3, the recess 2 being of somewhat larger diameter than the body portion of the cartridge. My invention is concerned with the provision of an annular rib i at or near the end 55 of the cartridge that is foremost in the blasting recess, Figs. 1-3 illustrating such a rib d welded to the head portion 5 or said cartridge near the rounded end thereof, forwardly of the obliquely arranged openings 8 through which the blasting gases pass into the coal body 8. The rib 4 is of 6 such outside diameter as to pass through the blasting recess 2, but to fit closely enough therein to prevent the gases from passing forwardly of said rib. By this arrangement, the discharge blast has a tendency to force the cartridge fur- 10 ther forward into the recess, it being noted that the rib 4 creates an area for the forward pressure of the gases that is larger than the area on which the rearward pressure of the discharge blast can act. The rib 4 prevents the blast gases from working forwardly of the head 5 of the cartridge and thus exerting a pressure on the front end to force the cartridge from the recess. The oblique arrangement of the openings 6 not only initially directs .the discharge of the blast away from the end of the cartridge which is provided with the sealing rib tolessen the sealing operation which must be performed by the rib d but the force of the discharging blast toward the outer end of the cartridge also produces a re- :5 action tending to hold the cartridge in the recess. In other words, the high pressure blast of gases issuing out of the rearwardly inclined discharge openings at high velocity will react upon the surrounding walls of the recess, producing a 80 resultant force tending to project the entire cartridge further inwardly toward the closed end of the recess. I

As illustrated in Fig. 4, the head of the cartridge is provided with a projecting stem 20 at 85 the end of which is a disk 2| of larger diameter than the body of the cartridge, this disk having the same function as the rib 4. A

In Figs. 5 and 6 is illustrated a modification wherein the blasting cartridge has a flat frontdll face and a projecting annular rib 4b is formed integral with the cartridge.

A sealing washer 3| of any desired construction may be secured to the rib 4b, Figs. 5 and 6 showing the washer 3i mounted against the rear face of said rib 4b. This washer has a rearwardly facing skirt portion 32. The forward pressure oi the blast gases ,will crowd the sealing washer into thespace between-the'rib and the blasting recess, thereby sealing off the forward end of the recess against the entry of blast gases.

In the modification shown in Figs. '7 and 8,

a sealing ring 40 has an inturned flange portion 4| overlapping the head of the cartridge and secured in place by means of a plate 42 riveted or otherwise secured to the head of the cartridge.

All of the above described constructions provide an enlarged portion that is seated in the blasting recess and sealed to prevent the blasting gases from working forwardly of thecartridge. The rib alone makes a satisfactory seal under most conditions, so that thersealing washer may commonly be dispensed with. The cartridge is effectively held in the blasting recess against any rearward movement. It is noted that by reason of said rib, the area against which the forward pressure of the gases can work is considerably larger than the area against which the rearward pressure of the gases can work, so that the whole tendency of the blast is to force the cartridge deeper into the blasting recess.

Obviously, the invention is applicable generally to blasting cartridges of various types, regardless of the blasting medium and blasting methods employed; so that I do not wish to be limited to the details 01' construction above shown and described.

ing charge is released in the general direction of the remaining end of the container, and blasting charge sealing means of greater effective diameter than and attached to the first mentioned and of'the container on the side of said discharge orifice away from the direction of release of the charge, said sealing means being constructed to substantially fit the bore hole and thereby prevent the blasting charge from working past the said means,'said sealing means and oblique discharge orifice serving to prevent a tendency for said cartridge to be forced out of the bore hole upon release of said charge when the cartridge is placed the bottom thereof.

CLARENCE J. SANDOE.

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