US2433543A - Means for positioning explosives in boreholes - Google Patents

Description

Dc. 30, 1 947. J. BISCH 2,433,543

MEANS FOR POSITIONING EXPLOSIVES IN BORE HOLES Filed Jan. 5, 1944 -9 6 I I I 'INVENTOR. v E BY Patented Dec. 30, 1947 MEANS FOR POSITIONING EXPLOSIVES IN BOREHOLES James L. Bisch, Valencia, Pa., assignor to Atlas Powder Company, Wilmington, Del., a corporation of Delaware Application January 5, 1944, Serial No. 517,142 2 Claims. (01. 1o2 22) A primary object of the invention is to provide a simple and inexpensive means for lowering large explosive cartridges into bore holes in such manner that while the cartridge is not ruptured to any material extent prior to its disposition at the bottom of the bore hole, it may thereafter, and through the medium of the lowering means, be so ruptured as to facilitate eflicient packing or tamping of the explosive in the bore hole.

Some of the explosive cartridges used in blasting are quite heavy, weighing 50 pounds or more. Heretofore it has been the practice. to equip individual cartridges with some form of device to which a lowering cable or rope could be attached. In some cases the individual cartridges, when manufactured, have been provided with string ties, fish net containers or a tape lowering device. These devices have not only increased the expense of manufacture, but they are more or less troublesome to attach.

The device of the present invention need not be packed with the cartridge, it may be used over and over again and it not only serves its function of supporting a cartridge while the cartridge is being lowered into a bore hole, but

it is so constructed as to rupture the cartridge shell as it is being disengaged from the cartridge. This rupturing of the shell makes it much easier to spread the shell and its contained explosive under tamping action. Thus, the device of the present invention not only serves to efficiently lower the cartridge, but it facilitates the achievement of a greater density of packing of the explosive in the bore hole.

The construction and method of use of the invention will be best understood by consideration of the accompanying drawing, wherein:

Fig. 1 is a side view of one form of tongs;

Fig. 2 is a side view of a modified form of tongs;

Fig. 3 is a sectional view upon line H of Fig. 1;

Fig. 4 is a reduced view of the tongs of Fig. 1, illustrating the manner of applying the same to an explosive cartridge.

The invention contemplates the provision of a tong-like structure comprising the legs 5 and 6 which extends from a resilient loop I of one or more turns. This structure is made of some non-sparking spring material, such as bronze or phosphor bronze wire. At their lower ends the legs are provided with vertical runs 5a, 6a, which terminate in inturned, upwardly inclined hooks B and 9. The tension of the loop I is such as to maintain the hooks in a position where upper'edges of the hooks are sharpened. In the use of the device a lowering cord or cable is attached to the loop 1 and the cartridge engaged by the tongs as described is lowered into a bore hole. After the cartridge has reached its position of rest at the bottom of the bore hole, or resting upon previously deposited cartridges, the lowering device is given a sharp upward jerk which causes the sharpened hooks to out vertically through the side walls of the shell and also to cut through the crimped-over portion of the shell formed, usually, by the folding over of the material of the shell to close it. It will be observed that the hooks 8 and 9 are upwardly inclined and thus, under the upward pull described, these hooks tend to move inwardly rather than outwardly and this insures the efiicient cutting of the cartridge shell, as.described. The structure of Fig. 2 is like that of Fig. 1 except that here it is illustrated that the runs 5a, 6a may be extended to provide a carrier for additional hooks l0 and H. These hooks may engage the cartridge at a lower point and thus provide not only additional support for the cartridge but an additional cutting means for rupturing the cartridge shell through a longer path. In this form of the invention each leg carries two hooks, instead of one.

The rupturing function of the two hook device of Fig. 1 is to cut through the crimp and get a tear started. In the four hook device of Fig. 2 much longer tears are made in the wrapper of the cartridge. In either case the explosive material is not exposed either outside the bore hole or while the cartridge is being lowered. The explosive material is not exposed until the cartridge is actually in place and the time has arrived for the tamping of the same to spread and pack it in the bore hole preparatory to the firing of the charge.

It is contemplated that the tongs will be made in different sizes to fit cartridges of varying diameters. It is also contemplated that the shape and degree of sharpness of the hooks will be varied in the manner necessary to secure the desired result. For example, with a relatively light Weight cartridge the hooks may be sharper and their bottom edges narrower than in the case of hooks used for lowering heavy cartridges. The reason for this will be readily understood. In the case of the heavier cartridge the inertia of the cartridge makes it possible to give a much stronger jerk on the lowering line without lifting the cartridge, than would be the case with a lighter cartridge. Thus, when lowering the heavy cartridge a hook not so sharp would be used toinsure that the lowering device would not cut its way out of the cartridge under the weight of the latter during the lowering operation. In handling some heavy cartridges the hooks may take the form of pointed rods. Other shapes of hooks may be employed. Also, in some cartridges, the explosive content is of such consistency as to provide a much firmer support for the hooks than is the case with other cartridges. Therefore, it should be understood that the configuration of the hook isdefinitely dependent upon the Weight of the cartridge and the consistency of its explosive content, which renders these tongs of special application and removes them from the class of mere lifting tongs, such as ice tongs, and the like. While I have illustrated a tong-like structure having only two legs .engageable with a cartridge at points 180 apart, it is clear that. it would be merely an extension of the idea to provide a tong with three legs engageable at points 120 apart or one with, four legs engageable at points 90 apart, etc. Therefore, the term tong-like, as herein used, is to be broadly construed. The invention, is not limited to the precise construction Shown and described, but includes within its purview whatever changes fairly come within-either the terms or the spirit of the appended claims.

Having described my invention, what'I claim is:

1,. A device for lowering into bore holes explosive packages comprising a body of explosive material and a wrapper for the same having a crimped over top, said device consisting of a tonglike structure comprising a plurality of substantially parallel legs provided with inturned upwardly directed hooks adapted to be thrust into the sides of the explosive package through the wrapper thereof, said hooks being substantially triangular shaped in cross-section and sufficiently sharp upon their upper edges to slit the wrapper and cut through the crimped top thereof when given a sharp upward jerk with respect to the explosive package, the lower sides of said triangular shaped hooks being sufliciently wide to support the weight of the explosive package without cutting out of the same in the absence of such sharp upward jerk.

2. A device for lowering into bore holes explosive packages comprising a body of explosive material and a Wrapper for the same having a crimped over top as claimed in claim 1 wherein each of said plurality of legs is provided with a plurality of said inturned hooks, said hooks on each leg lying in a common plane and being spaced from each other longitudinally of the leg.

JAMES L. BISCH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,807,819 Altgelt June 2, 1931 127,012 Bacher May 21, 1872 511,238 Hieatzman Dec. 19, 1893 1,468,718 Kneeland Sep. 25, 1923 2,353,458 Greene July 11, 1944 2,281,103 MacDonald Apr. 28, 1942 1,588,427 Karollus June 15, 1926

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