US 2578556 A
Description (OCR text may contain errors)
3 Sheets-Sheet l G. JOHNSTON SAFETY EQUIPMENT FOR JAILS, BANKS, AND THE LIKE .u N m E @5 M W Z .IJJ V W I F fi W m m 1! 6 J 6 00 M W rl n @e m r 'ilm I 6 m f I" v.i|r.|I|!i[I.v\| a V Dec. 11, 1951 Filed Jan. 30, 1946 ATTORNEYJ De. 11, 1951 JOHNSTON 2,578,556
SAFETY EQUIPMENT FOR JAILS, BANKS, AND THE LIKE Filed Jan. 50, 1946 3 Sheets-Sheet 2 K J g Q i/ v V 10 27 i 27 4 /6 INVENTOR ms/w/0WJ0/msr0/V 33 BY /J4 m/ u am ATTORNEYJ Dec. 11, 1951 G. JOHNSTON 2,578,556
SAFETY EQUIPMENT FOR JAILS, BANKS, AND THE LIKE Filed Jan. 30, 1946 3 Sheets-Sheet 3 l N V E N TO R Gram How Jam/5m ATTORNEYS Patented Dec. 11, 1951 OFFICE SAFETY EQUIPMENT FOR JAILS, BANKS, AND THE LIKE Greenhow Johnston, Richmond, Va. Application January 30, 1946, Serial No. 644,381
The invention relates to a safety equipment for jails, banks, stores, and the like.
It is an object of the present invention to provide for jails, banks, stores, and other buildings, a safety equipment provided with means for signaling and otherwise notifying officials and others should the bars or windows, doors or the like, or the hinges and bolts of doors, be tampered with in an attempt to break out of jail or to break into banks, stores, or the like provided with the safety equipment.
A further object of the invention is to provide means for effectively preventing the bars of doors, windows, and the like, from being cut by saws, acetylene torches, or other means and for shocking, killing, or seriously injuring any person attempting to escape from jails or break into banks or other buildings should a bar or bars be cut to an extent to operate the protective safety features or should a bar or bars be bent to any considerable extent.
Another object of the invention is to provide a safety bar having a fixed outer tubular shell or member and an interiorly arranged gas and fluid pressure chamber, an explosive chamber, and one or more intervening compartments formed by rotary and longitudinally movable tubular members and adapted tov contain gas or liquids such as acid, oil, or other fiuid under pressure and capable of being released by the cutting of the safety bar.
It is also an object of the invention to provide means for exploding the explosive charge simultaneously with the release of gas and liquids should the cutting of the safety bar extend beyond the gas and fluid pressure chamber and rotate one of the interior tubular members.
It is also an object of the invention to provide a window frame having hollow gas and liquid tight top, bottom, and sides, and adapted to contain gas and liquids under pressure so that any penetration of the window frame will result in detection of the same.
A further'object of the invention is to provide a visual and audible alarm adapted to be located at a remote point and having a light and bell or similar signaling means associated with' each of the safety bars for indicating not only the cutting of a safety bar or the bendingof the same but the particular bar or bars operated on.
Another object of the invention is to provide a safety bar comprising fixed and rotary tubular members having thick and thin portions for controlling the direction of the firing-or discharge of the explosive contained within the safety bar and for positively directing the firing or discharge either inwardly or outwardly as desired so that in the protection of banks and other buildings the discharge will be exteriorly of the same while with jails or other places of incarceration, the firing may be solely interiorly or both interiorly and exteriorly.
It is also an object of the invention to provide means for enabling the explosive charge to be exploded either by mechanical or electrical action.
With these and other objects in view, the invention consists in' the novel construction, ar-
rangement, and combination of parts hereinafter fully described, illustrated in the accompanying drawings, and pointed out in the claims hereto appended, it being understood that various changes in the form, proportion, and minor details of construction may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.
In the drawings:
Fig. 1 is an elevation partly in section of a window provided with safety bars constructed in accordance with the present invention.
Fig. 2 is an enlarged vertical sectional view of the lower portion of one of the safety bars and the top and bottom of the window frame.
Fig. 3 is a similar view of the upper portion of the safety bar and the top of the window frame.
Fig. 4 is a horizontal sectional view of a safety bar taken on the line 4-4 of Fig. 2.
Fig. 5 is a horizontal sectional view of the safety bar taken on the line 55 of Fig. 3.
Fig. 6 is a detailed sectional perspective view illustrating the construction of the ratchet mechanism at the lower end of the safety bars, the gas and fluid chamber being omitted for convenience of illustration.
Fig. 7 is a detailed sectional perspective view illustrating another form of the invention in which the outer shell and the rotary tubular members are provided with a single thick portion and a single thin portion for controlling the direction of the firing of the explosive charge.
Fig. 8 is an enlarged horizontal sectional view of the same.
, zontal safety bars located at the top and bottom of the window frame.
Fig. 15 is a detailed sectional view mu g;
another manner of mounting the trigger.
Fig. 16 is a detailed sectional view showing the safety device applied to a sliding bolt H Fig. 17 is a detailed sectional view showin g a mercury switch arranged to be operated 'bya Within the outer tubular member or bar 9 is arranged a gas and fluid pressure chamber in, a central explosive chamber II, and outer and inner intermediate tubular members l2 and I3 which are spaced apart and also spaced from the central explosive chamber by spacing rings I4 and E5 of insulating or any other suitable material.
.The gas and fiuid pressure chamber. is preferably formed. by a lead container which may hold liquid such as oil and gas under pressure and the spacing of the tubular members I2 and I3 from each other and from the explosive chamber ratchet member for exploding the explosive charge.
Fig, 18 isa detailed sectional view showing a circuit closer arranged to' be operated}- by a ratchet bar for closing a circuit for exploding the explosive charge;
In the accompanying drawings, in which are illustrated the preferred embodiments of the invention, 'l. designates a window frame constructed of metal or other suitable material and composed of hollow horizontal "top and bottom por-' tions and'verti'cal side portions. The top portion is providedwith upper and lower walls 2 and 3 and the bottom portion is provided with upper and lower walls 4 and 5. The hollow window frame is'designed to be madeair and water tight to enable itto form'a compartment extending entirely around the'window for vholding gas and liquid under pressure or any other fluid which, when the window frame is punctured, will escape and'indicate such fact. 7
The opening enclosed by the window frame is partially closed by a plurality of vertical safety bars 6 extending through'the upper wall of the bottom portion of the window frame and through thelower wall of the upper portion of the window 'frame and rigidly connectedby'wel'ding or other suitable means to the top and bottom of the windowframef M Each of the side portions of the window frame is provided with two pairs' of safety bars 6 extending from the top to the bottom offthewindow frame and 'rigidlyisecured at theiren'dsto the same. The 'pairs'of safety bars 6 located in. the
side. portions of. the window frame are located between"pair's of'horizo'nta1 safety bars 1. and 8 which. may be constructed as illustrated in detail in Fig, 10 of the drawingsi.
The window illustrated in Fig. l of the drawings, as an example; may constitute the window of a jail or other place of incarceration but the present safety equipment is applicable to" banks and other buildings for preventing breaking into the same. Thewindow frame is designed to be mounted, in concrete or fixed in positionin any other suitable manner.,.
Each of the safety bars 6 off the same construction. and a detailed description of oneof the. safety bars 6 willapplyto. each of the other safety bars and I will form an ample explanation of the same.
H The safety. bar .6 comprises. in itsconstruction an outer tubular member or bar 9' constructed of steel or any. othersuitable material. and presenting the appearance of an ordinary round bar such as is. used in the. doors and windows of prisons and other barred windows or. doors.
provides annular compartments for other similar lead containers (not shown) for holding gas and liquid.
Lead or any other suitable material may be employed in'the construction of the containers which are designed to be of soft material so that they may be readily cut by a saw or other tools- The q i el i es Pe tainrs will release the gas and liduid which will flow from the safety bar and readily indicate that the same has .been tampered with. At thesame time, the gas contained within such receptacles may be a'teargas or any other form of telltale gas so that the tampering with the Safety bar may be quickly detected. The. container, which forms the'gas and fluid pressure chamber it extends throughout the entire length. of the safety bar.
The explosive chamber is preferably formed by a central tubular member extending from the, top to. thebottom or" thewindow frame. and containing a suitable explosive I6 which may be detonated by a cartridge 1! or by electrical means such as a fuse.
The cartridge and the firing mechanism are located within the top hollow portion of the window frame and the central tubular member l8 is provided with a reduced cylindrical portion or chamber IS in which -is placed the cartridge H.
The chamber i9 isenlarged at the upper end to.
receive the rim of. the cartridge which is in the form of a blank cartridge. and which is exploded by means of a vertically movable firin pin 20 slidably mountedin a bore of a guide block 2i and actuated by a coiled spring 22which is interposed betweenv the guide blo clc and a collar or flange 23- provi'ded .on the firing pin at a point adjacent the lower end .24.. whicl'ris "tapered for engaging and. exploding a center fire cartridge but any other desired form of cartridge and f1r ing; pin may of course be employed. When the cartridge is fired b the firing pin it will, produce an explosion of theexplosive charge It.
The firingfpin isheld retracted by means of trigger 25 pivotally mounted in a slot 28 in the upper portion of the central tubular member I8.
The inner end of the tri ger extends beneath the collar and its outer end is arranged within a recee's 27 in the tubularv member ,I3.. The pivot 28.
perhorizontal portion of the window to permitv vertical movementand the said members l2 and. lg are also capable ofrotarmmovement. Each.
is provided at its lower end with ratchet teeth 29 which are normally arranged in spaced relation with corresponding ratchet teeth 3!} of a tubular ratchet member 3| rigidly secured to the window frame in the bottom thereof and provided at intervals between its teeth with insulation 32 in the form of blocks or pieces which are adapted to support the tubular ratchet member in spaced relation with the teeth of the fixed ratchet members 3|. Any attempt to file or cut the tubular member I2 will result in a rotary movement and a simultaneous upward longitudinal movement sufiicient to cause the teeth 29 and 30 to engage one another and close an electric circuit for operating either an alarm or for subjecting the person operating on and producin such rotary movement of the tubular member l3 to the effect of a high voltage current which may be of any voltage for producing the desired result. It will thus be seen that the rotary movement of the tubular members |2 and I3 will cause the ratchet teeth 29 and 36 to engage one another and will also result in an operation of the trigger 25 either by releasing the firing pin by pivotal movement or by breakage of the shearing pin.
High voltage wires 33 and 34 and lead wires 35 and 36. are designed to be connected respectively with the tubular member [2 and the tubular member l3 and both sets of wires may be connected with the tubular member l2 and insulated from each other so that an alarm 3? may be operated by rotation of the outer tubular member IL.
In order to afford directional control of the firing of the explosive charge, the fixed outer tubular member or shell 9 is provided with thick portions 38 and thin portions 39 and the intermediate tubular member I2 is provided with thick and thin termediate tubular member 3 is provided with thick and thin portions 42 and 48. The thick and thin portions of the tubular members of the safety bar are located at diametrically opposite points and the thin portions are arrangedopposite one another so that when the charge of dynamite or any other explosive'is exploded the charge will be fired or blasted through the thin portions which may be inwardly or outwardly with respect to the cell of a jail.
- When the safety device is applied to banks and other buildings and it is desired to have the explosive charge fired outwardly, the safety bars will be constructed as illustrated in Figs. '7 and 80f the accompanying drawings in which all of the thin portions 44, 45, and 46 are located at the same side of the safety bar. The thick and thin portions of the shell and rotary members extend longitudinally thereof throughout the length of the same and the thick portions provide protective areas which may be arranged for shielding the interior of a bank or other building and which are also adapted to concentrate the effect of an explosive charge in the desired direction. In this form of' the invention, the
tubular members are provided with a limited number of ratchet teeth 47 which are located in an arcuate recess 48 in the upper edge of a ratchet member 49 which is provided with spaced teeth 50 and an intermediate block or piece of insulating material which normally maintains the teeth 41 and 59 out of contact with one another. By this construction only a slight rotary movement of the tubular ratchet members is permitted but this is suificient to operate a trigger 52 mounted ,on' a horizontal shearing pin portions 30 and 4| and the in one direction or the other. the form of a spiral slot or groove of any desired 6, 53 or a trigger 54 mounted on a vertical shearing pin 55.
By means of the form of the invention illustrated in Figs. 7 and 3, barred windows of a bank,- store, or other building are aiforded, complete protection without liability of any injury to the bank or other building by the explosion of the explosive charge contained within the safety bar.
The lead wires 35 and 38 may be of any desired length in order to locate the electric signaling means 31 at a point remote from prison cells, as, for instance, in a'guard room, wardens ofiice, or other desired location. The electric signaling means preferably consist of bells 56 and lights 51 which are mounted on a, block 58 of insulatingmaterial. Feed wires 59 and 60 extend into the block and are suitably connected with the signaling means and in practice a separate pair of signals, a lamp and a bell, will be associated with each of the safety bars of the safety window and will be numbered or otherwise marked so that a bar being tampered with will be accurately indicated by the signaling means.
The horizontal safety bars in the top and bottom of the window may be constructed as illustrated in-Fig'. 10 of the drawings and consist of a fixed outer tubular member or shell 5| and an inner rotary tubular member 62 which, when rot'ated, will be simultaneously moved longitudinally in one direction or another sufficient to op-' crate one or the other of circuit closers 63 electrically connected with the electric alarm mechanism, whereby when the bar 52 is rotated and moved longitudinally by an attempt to file or cut the same, an alarm will be sounded and a light shone which will indicate the particular bar being operated on.
In Fig. 10 of the drawings, the tubular member 62 is provided with a cam slot 64 which is engaged by a fixed lug 65 of a rod 66 suitably anchored in the adjacent concrete or by any other suitable means so that when the tubular member 62 is rotated, it will be moved longitudinally in The cam may be'in length to secure the necessary longitudinal movement of the tubular bar or member 52. Instead of the cam slot, the longitudinal movement of the tubular member 62 may be effected by ratchet teeth located at one end of the bar and maintained in cooperative relation by means of a spring located at the opposite end of the bar similar to the arrangement disclosed in Fig. 12 of the drawings.
The safety bars may, as illustrated in Fig. 11' of the accompanying drawings, be equipped with only a single tubular rotary ratchet member 61,
but it will be clear that any desired number of the tubular rotary ratchet members may be employed and any number of the liquid containers.
within the capacity of the safety bar may be used.
In Fig. 12 of the drawings is illustrated a door hinge equipped with safety means constructed in accordance with the present invention. The
female member of the hinge is provided with upper and lower eyes 68 receiving between them an eye 69 of the male member and connected therewith by a vertical pintle ID. The eyes 58 and 69 are provided with rotary longitudinally j movable ratchet members H and 12 provided at one end with ratchet teeth 13 or M which engage fixed ratchet members 15 or 16. The ratchet teeth are maintained in engagement by means of coiled springs l1 or 18 so that when any one of the. ratchet members is rotated it will be moved longitudinally and will operate a; circuit closing device designed to be arranged in circuit with a1 suitable alarmmechanism for indicating-that the hinge is being tamperedwith.
The pintle 101's tubular and has arranged with in it a vertical ratchet member-x179 capable of,
vertical and. .rotary movement andprovided; at:
its lower end-.withqratchet teeth 80zvvhich5cooperate with ratchet teeth .81 .ofa fixed ratchet memberBZ; :The ratchet member-1,19 is main-.-'
tained in..;cooperativerelation with :the fixed ratchet member 82 ,bygravity'and the cooper.-
ating ratchet teeth of :the hinge are. constructed,
ratchet member is rotated; 'A safety hinge is: thus provided which will operate an alarm should any attemptbe made to cut through .the eyes. or the pintle of the safety hinge.
In Fig. 16 of the drawings is illustrated a-hollow sliding bolt 83 containing a ratchet member 84 mounted in a suitable guide and provided at one end. with ratchet teeth 85 and engaged at its other end by a coiled spring 86 which malntains the ratchet teeth 85 in proper relation with ratchet teeth .81 of a fixed ratchet member 88. Any attempt to cut. through the sliding boltwill cause a rotation-of the ratchet member 84 and'a longitudinal movement of the same sufficient to operate a. circuit. closing means designed to be connected in. circuit with alarm mechanism for indicating that the bolt is. being tampered with.
In Fig. 14. of the drawings is illustrated the mounting, of a trigger 90 in a bracket 9i fixed to the window frameand controlling atone end a firing pin 92 and having its other end extending intoa recess 93 of a rotary ratchet member 94 constructed similar to the ratchet members heretofore described. The trigger 9.0, which is pivotally mounted by a. shearing pin 95, is adapted to be operated by the bending of thesafety, bar in addition. to a rotary movement of the ratchet member .94 so that any bending of the safety bar. will release the firing pin and will fire a cartridge intothe explosive charge. The shearing pin 95 is arranged vertically so that the trigger 90 may be, swung out of engagement with the collar'or flange of the firing pin 92 for releasing the latter. .Also upward vertical longitudinal movement of the tubular member 94 will swing the inner end, of the trigger upwardly and shear or rupture the'shearing pin 95 and release the firing pin. The bending of the safety barjinwardl'y or outwardly will either rupture the shearing pin orcarry the'outer end of the trig ger out of engagement with the collar or flange of the firing pin and release the latter.
In-Fig. 15, of the drawings, the. mounting ofthe trigger 54 on a vertical shearing pin 55 is illustrated in enlarged detail.
A mercury switch 96, shown in Fig. 17; which is designed to be electrically connected with'means for exploding an explosive charge, is adapted to be operated by a vertically movable ratchet member 91 and in Fig. 18 a circuit closing devic'e98' is arranged to beoperated by a ratchet. member 99 for closing acircuit for exploding an explosivecharge. Any other equivalent means may of course be provided for this purpose.
The containers may contain only gas or only liquid or a combination of the two with or. without pressure and the ratchet teeth of the tubularmembers have a camming action in producing orefiecting longitudinal movement of the' rotary tubular members. This rotary and longitudinal movement or the tubular ratchet members will effectually prevent a saw from cutting through the safety-bar as the rotary and upward and downward movement'of the tubular members-will tend to break saws, making it almost impossibletoout through these memberst The movement otthe' tubular members may be varied and: in F ig. 6 aid-additional tubular member I99 issillustratedr It will also be noted that when a chargeof explosive materialis. exploded and-the thinportions of thesaiety bar are blasted or blown out, the thick portions 'of the :bar will remain intact and such. .explosionwill'not afiorda prisoner any opportunity tdescape. 5.. x
In practice,g.the'rotary tubular members. 12 oftthe safety-"bars andztherfixed ratchet members. which cooperate with .the'tubular. members. l2 will allbe in.cireuit;.so.that theahigh voltage circuit may be closed by .an operationof anyone of the rotary tubular members it... The. rotary-tubular members t3. and their associated fixed ratchet members will be in.circuit withtheir respective. signals so. that when anyone of the. rotaryetubu i 1 lar members is -is;.operated,-;the proper signals of the signaling means: will be operated forindicating the particularone of: the safetybars. being tamperedwith.
. What isclaimed is:
1. Safety equipment-of the -class;-.,describ.ed .in-.' cluding a fixed outerimperforatetubular shell in the form of-a bar .for jails, banks and the:
like, a tubular member arranged withirrsaid shell? and extending throughout the length of the same and spacedfrom saidshellto :provide aninter vening space,- and asoft metal tubular fluid con-e tamer located within said intervening spacebe-a, tween the tubular member and the shellv andhaving inner and outerwalls substantially concentric; with the .tubular shell, said container being arranged inla position tobecut and have its contents released in the event ofthe cutting of the, shell andcapable of discharging its contents solely through the cut.
2. Safety equipmentof the class described including a. fixed outer tubular shell, a container: arranged within the. shell and having acharge oi explosive material,. a rotary member located within the shell and-arranged to berotated by a file, saw,-or the like cutting throughthe shell, means contained within the shell and associated with thecharge of explosive. material andwith; said rotaryv memberand operableby an upward longitudinal rotary, movement. of said member for exploding said charge. of. explosive material, and camming means responsive. to the rotary movement of said member for positively movingthe same longitudinally in an'upward direction;
'3. Safety equipment .of the class. described including a fixed tubular shell, a rotary member located in .said' shell, .camming means including normallyspaced contiguous portions arranged to engage each other-for effecting'a positive upward longitudinal movement of said member when the" same is rotated, a charge of explosive material located within theshellyand means operatedby said upward longitudinal movement of said member for exploding said charge of explosive-'- the same is rotated, a charge of explosive ma-' -terial located within the shell, and means operated by th'elongitudinalmovement or said mom- .9 v. ber for exploding said charge of explosive material.
, 5. Safety equipment of the class described in- I cluding a fixed shell, a rotary member located in said shellrand provided with ratchet teeth, a
fixed ratchet member having teeth arranged to be engaged by the teeth of the rotary member, whereby the latter when rotated will be moved longitudinally by said teeth, a charge of explosive material located within said shell, and means operated by the longitudinal movement of the rotary member for exploding the charge of explosive material.
6. Safety equipment of the class described including a fixed horizontal tubular shell, a horizontal rotary tubular member located in said shell and, camming means, fixed means engaging the cam for effecting longitudinal movement of the rotary tubular member when the same is rotated, and a circuit closing device arranged to be operated by the longitudinal movement of the rotary tubular member.
'7. Safety equipment of the class described including a fixed tubular shell in the form of a bar for jails, banks and the like, a rotary tubular member located within the shell, a charge of explosive material also contained within the shell, means operated by rotary movement of said member for exploding said charge, said shell' and member beingprovidedwith diametricallyopposed thick portions and diametrically opposed thin portions arranged respectively adjacent each other and extending longitudinally. for directional firing of the exploded charge through said thin portions and the thick portions providing longitudinal protective areas throughout the length of said bar.
8. Safety equipment of the class described including a fixed tubular shell, a central tubular member containing an explosive charge and having a cartridge receiving chamber, said member being disposed in spaced relation with said shell, a rotary tubular member arranged within the shell in the space between the central tubular member and said shell, a spring actuated firing pin arranged to discharge a cartridge in said chamber, a trigger for holding the firing pin in a retracted position, said trigger being pivoted for horizontal movement to engage and release the firing pin, and means carried by the rotary tubular member for maintaining the trigger in a set position, said tubular member operating through rotary movement to disengage the trigger and release the firing pin for exploding said cartridge.
9. Safety equipment of the class described including a fixed tubular shell, a central tubular member containing a charge of explosive and having a cartridge receiving chamber, a shearing pin mounted on the central tubular member, a spring actuated firing pin arranged to explode a cartridge in said chamber, a trigger mounted on said shearing pin and arranged to hold the firing pin in set position, and a rotary tubular member arranged between the central tubular member and the fixed outer shell and having means for engaging the trigger for maintaining the same in engagement with the firing pin, said rotary tubular member when rotated operating to shear the shearing pin and free the trigger and thereby release the firing pin.
10. Safety equipment of the class described including a fixed tubular shell, a central tubular member containing a charge of explosive material and having a cartridge receiving chamber,
a spring actuated firing pin mounted in the central tubular member and arranged to explode a cartridge in said chamber, a shearing pin mounted on said member, a, trigger pivoted to said member by the shearing pin and having one end arranged tohold the firing pin in set position, a rotary tubular member having a recess receiving the other end of the trigger and adapted through rotary movement to shear off said shearing pin and free the trigger to release the firing pin, and means operated by the rotary movement of the rotary tubular member for effecting longitudinal movement thereof for operating the trigger to release the firing pin through longitudinal movement of said rotary member.
11. Safety equipment of the class described including a frame, a safety bar mounted in the frame and comprising a fixed tubular shell, a rotary tubular member. a tubular container having a charge of explosive material and provided with a firing pin for exploding a cartridge, a rotary tubular member surrounding and spaced from said container, a bracket fixed to the frame and extending between the container and the rotary tubular member, a trigger privotally mounted by shearable means on the bracket and having one end arranged to engage the firing pin for holding the same in a retracted position and having its other end engaged by said rotary tubular member and adapted to be disengaged therefrom by a rotary movement of the tubular member pivotally actuating the trigger or a bending of the safety bar, whereby such bending in one direction will withdraw the trigger and release the firing pin and produce an explosion of the explosive charge and in the opposite direction will shear the pivot means and release the firing pin.
12. Safety equipment of the class described. including a fixed outer tubular shell, a rotary member located within the shell and arranged to be rotated by a file, saw or the like cutting through the shell, a charge of explosive material located within the shell, means for detonating the explosive material, trigger means operated by an upward longitudinal movement of the rotary member, said trigger means normally maintaining the detonating means inoperative, and camming means responsive to the rotary movement of said member for positively moving the same in an upward direction.
13. Safety equipment of the class described including a safety bar adapted to contain a charge of explosive and comprising a fixed outer tubular shell having thick and thin portions, an inner rotary tubular member having thick and thin portions, said thick and thin portions extending substantially throughout the length of the shell and the tubular member, and the thin portions of the tubular member facing the thin portions of said shell for directing the explosion of the explosive charge through said thin portions and said thick portions of the tubular member and said shell providing protective areas throughout the length of the safety bar, and means responsive to movement of the tubular member for exploding said charge of explosive material.
REFERENCES CITED The following references are of record in the file of this patent:
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501-142 H111 '1Ju1y-11, 1893 -a 763;890 :Henriksen 1111mm, 1904 11670434 971x00 mew, Qc't; 1910 5 1. 1 1,094,043 Witsch .Apr.:21,.1914 y 12 Name r Date Kane Mar. 25, 1919