US2405507A

US2405507A - Charger for explosives

Info

Publication number: US2405507A
Application number: US466391A
Authority: US
Inventors: Edward K Lefren
Original assignee: Hercules Powder Co
Current assignee: Hercules Powder Co
Priority date: 1942-11-21
Filing date: 1942-11-21
Publication date: 1946-08-06
Anticipated expiration: 1963-08-06

Description

1946- E. K. LEFlEN 2,405,507

CHARGER FOR EXPLOSIVES Filed Nov. 21, 1942 INVENTOR.

BY EDWARD K. LEFRE/V W Q\Ma.-

Patented Aug. 6, 1946 CHARGER FOR EXPLOSIVES Edward K. Lefren, Port Ewen, N. Y., assignor to Hercules Powder Company, Wilmington, DeL, a corporation of Delaware I Application November 21, 1942, Serial No. 466,391

3 Claims.

This invention relates to an improved machine for charging detonator shells and similar articles with explosives.

Heretofore equipment used for the chargin Having now indicated in a general way the nature and purpose of this invention, there follows a more detailed description of the preferred embodiment thereof with reference to the accomof detonator shells With explosives has not been panying drawing in which: provided with means adapted to insure a uniform Fig. 1 is an elevational View, partly in section, weight of charge of explosive. It is common pracshowing the improved explosive charging device tice in charging detonator shells to dump the ex in charge receiving position. plosive on the top side of a charging plate con- Fig. 2 is a fragmentary view showing the device sisting of a plurality of explosive receiving bins in charge releasing position. or openings each having a fixed volume. The ex- Referring to the drawings, numeral 4 indicates plosive is then moved across the face of the plate a supporting means as, for example, a platform by means of a Wiper thereby filling the openings. or a table supporting the explosive charger indi- The excess explosive spills over the edges of the cated generally at 5 through leg supports 6. An charging plate into a suitable catch means. The e p os ve releasing means or dump plate I is held charging plate is then moved into shell loading in fixed position by means of said legs 6 in spaced position in order to dump the fixed volume of relationship with said support 4. The dump plate explosive into a detonator shell. This method of l is provided with a plurality of openings 8 unicharging by spilling the explosive into the charg formly spaced throughout the plate. The number ing plate openings permits considerable variations of openings depends upon the number of shells in the weight of the charge of explosive delivered desired to be charged at a single operation and toeach detonator or series of detonators, because may be as many as 500. variations occur in the volume of the charge Spaced from the dump plate 1 is an explosive (even though each opening in the charging plate storage means or plate 9 provided with a pluralit is of the same volume) due to the tendency for of explosive receiving bins or openings I0. These the wiper or explosive moving means to carry a bins may be conical in shape as shown and may portion of the explosive out of the top of some have a capacity sufficient to receive enough exholes and, in other cases, for the wiper to ride plosive to charge five or more consecutive series over the explosive leaving extra explosive on the of shells without the necessity of charging the charge plate opening. Furthermore, the weight bins with more explosive, of the explosive charge varies with the degree to The bins are charged by means of an explosive which it is packed, which varies with the amount storage means or hopper l l adapted to be slidof explosive being moved across a particular ably moved across the face of the storage plate charge plate opening. When varying weight 9 and into registry-with the openings it. As each charges of explosive are charged into a shell and R5 bin It] comes into registr with the moving hopthe shell is subjected to a pressing operation, per the explosive l2, which may be mercury fulthere is a tendency for the charge to be overminate, diazodinitrophenol,pentaerythritol tetrapressed in the case where an excess of explosive nitrate, etc., drops from the hopper into the bin. is charged, and to be underpressed when an in- Movement of the hopper is regulated to permit sufiicient amount of explosive is charged. When 10 complete filling of each bin. the priming charge of a detonator is overpressed, An explosive charging means or fixed Weight adefective detonator results which detonator may charge receiving plate or metering plate i3 is fail to explode when put into use. Defective detomovably positioned between th storage plate 9 nators are dangerous to work with and may result and the dump plate 1 and provided with explosive in loss of life. charge receiving openings or chambers Hi. There Therefore, it is an object of this invention to are as many chambersl l as there are bins I0 in provide a charging device for detonator shells the storage plate and openings 8 in the dump and the like, whereby a fixed weight of explosive plate. In order to reduce to a minimum the poscharge will always be delivered to the detonator, sibilty of the sensitive explosive l2 being accithereby insuring uniform pressing of the charge dentally detonated through pinching which would in the shell. occur should the explosive be caught between two A further object is to provide means for charghard surfaces, a soft rubber facing l5 and I6 is ing a detonator with a fixed weight of explosive placed on the surface of the storage plate and charge in an economical, efiicient and safe mandump plate, and soft rubber facing 23 and 24 is n91" 5.5 placed on the upper surface of storage plate 9 nator shells 2t.

glas es and on the lower surface of storage hopper II respectively. The charging plate I3 moves in sliding contact with and between the spaced rubber facings I5 and I 5 between guides I1 and I8 which limit the movement of the charge plate and permit positive alignment of the chambers I4 with the bins I0 and with the openings 8, respectively. Other guides (not shown) prevent movement of the charging plate laterally to its normal movement.

A suitable vibrating means as, for example. the

vibrating means I9 is attached to the table {land through its controlled operation the explosive I? may be packed in the chambers It to a; uniform density, Uniform density may be accomplished in the chambers I l, thereby resulting. in explosiv'e charge having a uniform density. Since each chamber i4 is of the same volume and each chamber is uniformly packed, then each shell will receive a fixed Weight charge of explosive.

Explosive receiving containers as, for example, detonater shells 26 are carried in a suitable support means as, for example, shell press block 2! which is slid. on the top side' of the table l'b'eneath the charger 5. Each shell is moved into registry or axial alignment with a corresponding opening 3 in the dump plate I by reason of the fact that the shell press block 2 i" is guided into a predetermined position fixed by means of the guides 22 and other stop means (not shown) located on the far side of the table 4.

The charger is operated by first moving the chambers I l'out of registry with the bins I6 by moving the charging plate is to the right relative to Fig. 1. This movement closes the bottom of each bin. The hopper II is then moved across the face of the storage plate 9 slowly enough to fill each bin with the explosive I2. The charging plate 'is' then moved to the left relative to Fig, 1 the guide Il stops the movement at a position where each chamber I l is in registry with a corresponding bin Ill, The explosive I2 drops from each bin into the chamber in registry therewith filling each chamber with a uniform amount of explosive. The charging plate is then moved to the right relative to Fig. 1 until each chamber is in registry with a corresponding opening 8 which movement is determined by means of the guide 58. The fixed weight charge of explosive drops through the opening 8- into corresponding deto- The shell press block is then removed from the table and another series of shells are moved into position under the charger and the same procedure repeated.

Occasionally the density of a batch of explosive to be charged will vary in respect to the density of another batch of explosive. This density variation is a function of the grain size of the explosive. Thus, it may be readily seen that when the grain size of the explosive is unintentionally increased, a lesser number of rains are received in the chambers I0 and consequently the resulting ill density of the charge will be less under a given condition of packing than when the regular and desired grain size of explosive is charged under the same conditions of packing. Where the grain size is smaller than the desired grain size, a greater number of grains of explosive will be received in the chambers and consequently the resulting density of the charge will be greater than when a regular grain size is being charged, In order to compensate for these occasional density variations, it has been found that the vibrator I 9 may be used to bring the density of the charge to a predetermined value regardless of the normal variation in" grain size which may occasionally occur.

It is apparent that the objects of this invention have been attained by providing an improved machine for charging detonator shells; that the machine in accordancewith the present invention permits uniform weight charging of detonator shells and the like, eliminates the spilling of explosive; all of which is accomplished in a more economical, efficient, and safe manner than heretofore realized.

What I claim and desire to protect by Letters Patent is:

l. In a device for charging explosive containers with a fixed weight of explosive, the combination ofa storage plate havinga plurality of explosive receiving bins therein; a storage hopper slidable over said storage plate; a dump plate with a plurality of openings displaced from axial alignment with said bins; and a metering plate in close fitting slidable relationship between saidstorage and dump plates and a plurality of chambers in said metering plate alignable in registry with the receiving bins and dump plate openings.

2; in a device for charging explosive containers with a fixed weight of explosive, the combination of a storage plate having a plurality of explosive receiving bins therein; a storage hopper slidable over said storage plate; a dump plate with a plurality'of openings displaced from axial alignment with said bins; a metering plate in close fitting slidable relationship between said storage and dump plates and'a plurality of chambers in said metering plate align'able in registry with the receiving bins and dump plate openings; and means fo'r'vibrating the aforesaid device.

In a device for charging explosive containers with a fixed weight ofexplosive, the combination of a" storage plate having a plurality of explosive receiving bins therein; a storage hopper slidable over said storage plate; a resilient facing between the storage hopper and storage plate; a dump plate with a plurality of openings displaced from axial alignment with said bins; a resilient facing on the lower side of said storage plate; a resilient facing on the upper side of said dump plate; a metering plate in close fitting slidable relationshipbetween resilient fa'cings on said storage and dump plates and a pluralit of chambers in said metering plate alignable in registry with the receiving bins and dump plate openings; and means for vibrating the aforesaid device.

EDWARD K. LEFREN.