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Publication numberUS2376420 A
Publication typeGrant
Publication dateMay 22, 1945
Filing dateJan 19, 1942
Priority dateJan 19, 1942
Publication numberUS 2376420 A, US 2376420A, US-A-2376420, US2376420 A, US2376420A
InventorsDavis Charles R
Original AssigneeDavis Charles R
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Safe protection
US 2376420 A
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Description  (OCR text may contain errors)

.May 22, 1945. C. RQ AWS 2,376,420

SAFE PROTECTION Filed Jan. 19, 1942 2 sheets-sheet 1y la7/gm, @www r fm/L A Trop/vas.

May 22, 1945.

c. R. DAVIS 2,376,420

sAFE PRoTEcT1oN Filed Jan. 19, 1942 2 sheets-sheet z /Z .5. 54' a 7 a 57 j j' l 4 :Hlm h ya 25 4 49 67 g f77 ,4 TTO/VEYS.

Patented May 22, 1945 UNITED STATES PATENT OFFICE 2,376,420 `SAFE PROTECTION Charles R. Davis, Rochester, N'. Y.

Application January 19, 1942, Serial No. 427,268

Claims. (Cl. 10B- 44) This' invention relates to burglar resisting safes and is' in the nature of a continuation in part of my copending application Ser. No. 111,670 filed November 19, 1936, now Patent No. 2,270,274', issued' January 20, 1942.

An object of this invention is to provide improved means for protecting a safe or strong box, and particularly the door and locking mechanism thereof, against tampering of a kind which might enable the box or safe to be opened by thieves or burglar-s, with which the protective device will be rendered effective automatically when the door andl locking mechanism of the box or safe are tampered with or mutilated in an eilort to open the door except by the usual manner of operating the locking mechanism, which is particularly suitable for use with combination locks, with which the protective means for the box will be ineiective when the door is unlocked, even though closed, but which will be rendered effective automatically by the act of locking of the door, and which will be relatively simple, effective, practical and inexpensive.

Another object of the invention is to provide improved, simple and eflicient means for protect.. ingthe door of a safe or stro-ng box when the door is locked, which is automatically rendered ineffective when the door is unlocked, and which will be Veffective against mutilation of the locking mechanism, against drilling, against any attempt to disable the look by pulling the spindle from the combination lock by means of a puller or punching the spindle inwardly.

Other objects and advantages will be apparent from the following description oi two embodiments of the invention, and novel features of the invention will be pointed out hereinafter in connection with the appended claims.

In the accompanying drawings:

Fig. l is an inside face elevation of the door of a safe or strong box, constructed in accordance with this invention, but with the removable plate ori-the inner face removed, a portion of the door casing broken away, and a portion of the adjacent wall of the strong box, against which the door abuts, shown in section, which corresponds to a section approximately along the line I--I of Fig. 2;

` Fig. 2 is a sectional plan of the same, with the section taken approximately along the line 2--2 of Fig. 1;

Fig. 3 is a diagram illustrating the electrical circuits of the protective system;

Fig. 4 is a sectional elevation of a portion of means, modified slightly' from thatshown in Figs. 1 to 3, and' with the circuitl shown diagrammeti/cally.y

5 is asectional elevation through a portion of the. safe: shown in, Figs. 1 to 3, immediately behind the; dial plate, and' showing the manner of mounting the dial plate.;

Fig. 6. is a sectional elevation through the combinationlockv mechanism of the door;

Fig. 7 is: a, sectional plan of details used for fastening the: dial plate in place;

Fig'.` 8` is a sectional, plan of a mounting for a conducting member and associated parts, and forming part of the embodiment of Figs. 1 to 3 and 5 to,y 7.

In the embodiment of the invention illustrated in Figs.` 1 to 3, and; 5. to 8, the safev or strong box I is of the type disclosed in my prior copendingapplication, Ser. No. 111,670 led- November 19, 1936, now Patent No. 2,270,274, issued January 20, 1942;.

safe. or strong box 'is providedA with a displaceable door 2 which is hinged to the opening of the strong box or safe in any suitable manner, such as Vby' hinges 3; The safe or box I is provided with a` hardened outer steel jacket or plate.y 4, and against the innerface of this plate 4 is disposed a relatively thin layer of insulating material 5, such as a thin layer of insulating varnish, or a layer oi Empire cloth which is an impregnated textile fabric commonly used for insulating purposes. Against the insulating layer 5 is disposed a plate or layer E of conducting material such as copper wire screening. This screen layer 6. and the insulating layer 5 abut each other face to. facev and flat. against the, inner face of the steel jacket 4. Against the screen E I dispose another layer 'I of suitable insulating material. Aiiller 8 of, heat insulating material such as plaster. of Pariser other suitable heat nsulating material4 is disposed to substantially ll the space between the insulating layer 1 and the inner wall 9 of the. safe which deiines the storage chamber. v

Similarly, the door 2 is, provided with an outer steel plate.. or layer I0, against the inner face of which is disposed a thin insulating layer I I similar to, the layer 5, and a conducting layer I2 is disposed flat against. the insulating layer I0. The

. layer I 2 may also beof copper wirescreening similar tothe layer 6., but it will be understood that metal foil or other electrically conducting material may lbe. employed as` the inner conducting layers 6 and I2. The layer I2 is also covered by the locking mechanism and circuit controlling an insulating 'layer I3 and thatin turn is. covered by a metal plate I4. The space between the plate I4 and the rear wall I5 of the door may be lled With a suitable filler I6, similar to the ller 8, except that space is provided for the locking and protective mechanism carried in the door. The inner wall or face I5 of the door may have a removable plate il to enable access to be had to the locking mechanism and electrical connections. This plate Il was removed in Fig. l, in order to show the interior of the door chamber.

The door is provided with a lock spindle I8 which extends through the plates or layers I0, I2 and I4 and insulating layers II and I3, and is insulated from the plates or layers, such as by mounting the spindle I8 in a ber bushing which extends through all of these layers. 'I'he spindle I8 carries an operating handle I9 on the outer end thereof. The inner end of the' spindle I8 is provided with a crank disk carrying, eccentric to the axis of the spindle, a crank pin 2I which engages in an elongated slot 22 in a cross head or yoke 23 which carries locking bolts 24y at opposite ends of the arms thereof. These locking bolts 24v are disposed to extend through alined .openings 25 in the abutting plates of the door and door opening of the strong box in order to lock the door. By moving the bolts 24 through the alined openings 25, the door may be locked in closed position, and -by retracting the bolts 24 entirely into the door, the door will be released so that it can swing into open position. The bolts are projected into locking position or withdrawn merely by rocking the handle I9 and through it the spindle I8. During this rocking of the spindle I9, the pin 2| acts as a crank in the slot 22 and causes reciprocation of the yoke 23 and locking bolts 24. The yoke or cross head 23 is also provided with an elongated slot 26, at right angles to the slot 22, which receives a guide pin 2'I projecting from the inner plate I4 and the slot 26, by the engagement of its opposite ends 22 with pin 21, limits the movement of the locking bolts 24, although the throw of the crank pin 2| would also serve the purpose.

Also mounted on the inner face of the plate I4 of the door is a suitable combination lock 28 having a plurality of tumblers which, when properly set, control the yoke 23 and locking bolts 24. Such combination locks are purchased in the open market and the details of the same, per se, are not a part of this invention except as specifically pointed out herein. The tumblers in such a lock are mounted on a metal spindle 29, see Fig. 6, which is rotatably mounted in bearings 30 and 3I disposed in a bushing 32 of insulating material such as of ber. The bushing extends through the metal plates IU, I2 and I4 and insulating layers I I and I3. A ber nut 33 is threaded upon the outer end of bushing 32 and serves to clamp a metal dial plate 34 against the outer face or plate I0 of the door 2, there being an insulating layer 35 disposed between the dial plate 34 and the plate I0 which is of steel or other electrically conducting material. A button 36 xed upon the outer end of the spindle 29, serves as a medium by which the spindle 29 may be rotated to set the tumblers to release the locking mechanism, or to lock the bolt mechanism, the tumblers being designated generally at 3'I in Fig. 6, and the spindle 29 extends on through the same.

The bearing 3| may have an annular groove in its periphery into which the adjacent end of the fiber bushing 32 may be forced, or vthe bearing 3l may be threaded into the interior of the passage of the bushing 32, and this bearing 3l has a shoulder portion abutting against the end of the bushing 32, which shoulder portion receives upon it one wall of a casing 38 which is secured against plate I4 by a nut 39 screwed upon the bearing 3 I. The spindle 29 projects through an opening 4D in the rear face of the casing 38.

A U-shaped metal bracket 4I straddles the casing 38 with the arms of the U extending toward the front of the door and spaced from the casing 38 by insulating strips 42 and 43. This bridge 4I is secured to the upper and lower sides of the casing 38 in. any suitable manner, such as by bolts 44 which are insulated from the easing 38, but electrically connected to the bridge 4I.

The spindle 29 extends through an opening 45 Ain the cross part of the bridge 4I and out of contact with bridge 4I, and on opposite sides of this opening 45, the spindle carries metal pins 4B which are normally slightly spaced from the bridge 4I, so that if the spindle 29 of the combination lock-is given an endwise movement in either direction, such as by pulling outwardly on4 the spindle with a wheel puller or similar device, or by driving the spindle inwardly, one of the pins 48 will contact with the bridge 4I and thus electrically connect the bridge 4I with the spindle 29. The spindle 29 carries a metallic disc or dial 4l which is electrically grounded or connected to the spindle 29, and overlies a substantial area of the dial plate 34, and the edge of the dial 4'I terminates in close proximity to but is slightly spaced from, the dial plate 34, with no insulation between them. Operated by the tumbler mechanism in the usual manner is a link 48. Figs. 1. and 2, which, when the tumblers are properly set and turned by proper manipulation of the button 36, will be moved' generally endwise.

This link 43 is pivotally connected to a locking lug or member 49 which is slidingly mounted in the casing 38, so as to extend beyond the casing 38 to some extent and be movable into the path of an upstanding iiange 59 on the yoke 23. Thus when the locking lug or member 49 is moved in an outward direction into the position shown in full lines in Fig. l., it abuts against the ilange 50 and prevents retraction of the yoke 23. When the lug 49 is moved inwardly it moves away from the flange 5B and releases the yoke 23 for movement in a direction to withdraw the bolts 24 from locking position.

The locking lug 49 carries an angular member 5I Fig. 1, and upon the free end of the member 5I I support a generally U-shaped metallic member 52. The member 52, see Fig. 8, is insulated from the member 5I by a washer 53 of insulating material, and a bushing 54 of insulating material passes through an aperture 55 in the member 52. and terminates in a iiange 56 at the face of member 5I opposite the member 52. A bolt or rod 51 of electrically conducting material such as metal, passes through the bushing 54 and the end of the member 52 which abuts against the end of member 5I. Nuts 58 and 59 are threaded i upon the rod 5I so as to abut respectively against vlill of insulating material which is threaded or tightly forced into an opening SI in themetallic side wall 62 of the door. The adjacent wall 63 of the door jamb against which the door abuts is provided with an opening 64 which is alined with the opening 6I when the door is closed and the rod 51 is movable or projectable through the opening 64 when the locking lug 49- is moved into locking position, as shown by full lines in Figs. 1 and 2. The rod 51 is spaced slightly from the peripheral wall of the opening 64 so that it is normally out of contact therewith when the door is locked.

The dial plate 34 is secured to thefront face of the door not only by the fiber nut 33, but also by other mechanism shown in Figs. 5 and '1, and which will now be described. The dial plate 34 and front wall I0 are provided with a plurality of alined openings through which pass bushings 65 of electrically insulating material, each of which at its outer end hasv a flange 66 which overlies the dial plate 34 sufficiently to confine the dial against the plate I8 of the door. A bolt 61 passes through each bushing 65 and at its inner end carries nuts 68. A washer 69 of insulating material is disposed between the nuts 68 and the rinner face of the plate Il), so that the bolt 61 is fully insulated electrically from both the plate I0 of the door and the dial plate 34. Three of such bolts 61 are illustrated, and in addition, a contact stud to be described presently provided for making an electrical connection to the dial plate.

Referring now to Fig. 2, the plates ID, I2"and I4 of the door and the insulating layers II and I3 are provided with alined openings through which passes a bushing 10 of insulating material. A bolt 1I passes through the dial plate 34, the insulating layer 35, the bushing 1I), and at its inner end carries anut 12. A washer 13 of insulating material is disposed between the nut 12 and the inner plate I4, and the end of a wire or conductor 99 is clamped between the nut 12 and the washer 13 so as to have an electrical connection'to the bolt 1I. The head of the-bolt 1I overhangs and engages the dial plate 34, so as to form an electrical contact therewith, and this places the dial plate in electrical contact with" the. wire 99. The bolts 61 which clamp'the dial plate to the front plate IIJ of the door and the bolt 1I are all disposed beneath and are protected by the dial 41.

The portion of the wall of the strong box along the door opening and against which the free edgel of the door abuts when the door is closed, is provided` with an interior chamber 1.5 into which the locking bolts 24 and rod 51 project when the door is locked. Disposed in this chamber 15 is a normally open switch formed with spring contacts 16 and 11, and these contacts at their free ends are normally spaced apart slightly and dis-` posed closely adjacent to the opening64through which the rod 51 may be projected, so that when the rod 51 is projected through the opening 64 intothe chamber 15, its end will engage with the contact 16, make an electrical connection therewith, and also force the latter into engagement with the other switch element 11, as shown in Fig. 1.

The electrical circuits will next be described.

Referring now particularly to Fig. 3, the strong box or safe is shown as supported on ak cabinet 1-8, as described in my prior application above identified, and in this base 18 is disposed a suitable protective device which may be an alarm 19, or a gas releasing device as described in my prior application, or any other suitable means for protecting the safe. For simplicity, itis shown merely as an alarm, but it willbe understood that this is not to be limiting, and that any suitable protective device may be employed. This device`19 is supplied withl operating current from a suitable, dependable source, such as a battery 86, one terminal of which is connected by a wire 8l to the protective device 19, the other side of the protective device being connected by a wire 82 to a normally retracted switch element -83 of a relay 84. y

The switch element 83 is movable by the relay into engagement with a contact 85 when the relay 84 is energized and this contact 85 is connected by a wire 86 to the other side of the bat-y the inner plate or copper screen 6 of the strong' box. The other side vof the battery 88 is connected by a wire 9| to the Aouter wall 4 of the strong box. A second, normally retracted, switch member 92 is also operated by the relay 84 into closed position, when the relay is energized, where it engages a contact 93. The switch member 92 is connected by a wire. 94 to the wire 9|, and the contact 93 is connected by a wire 95 to the wire 89. When the relay 84 is energized, it moves both switch members 92 and 83 into circuit closing position, and switch member. 92 then completes a shunt circuit, sometimes known as a holding circuit or stick circuit, through the battery and relay 84 to hold the relay closed, even though they original circuit through the relay 84 is later broken. The movement of the switch member 83 by relay 84 renders the. protective device effective, and since the relay locks itself ln closed i circuit condition through the switch member 92, this will cause the protective device to remain effective, even though the original circuit through relay 84 has been opened.

The rod 51, as explained above, is electrically connected to the member 52 and this member carries a clamping or terminal post or bolt 96, Fig. 1, to which a number of wires may be connected. One wire 91 electrically connects the terminal bolt 96 to the bolt 44 on the bridge Imember 4I, another wire 98 electrically connects the bolt 96 to the copper mesh screen or conducting layer I2 oi the door and still another wire 99 connects the clamping bolt 96 to the dial plate 34. The dial 41 is groundedthrough the spindle 29 to the outer plate I8 of the door and the latter to the outer plate 4 of the strong box through the hingles 3, and this grounding is indicated diagrammatically in Fig. 3 by the wires |00.

With the connections as thus explained, if the safeis unlocked, the rod 51will be withdrawn from the opening 64, the locking bolts 24 will be withdrawn into the door, and the door is then free to open or close. When the rod 51 iswithdrawn in this manner, it is out of contact with the switch contact 16 in the chamber 15, and the two contacts 16 and 11 are then out of contact with one another because these contacts 16 and 11 form a normally open switch. Current from the battery 88 is unable to flow because the circuit is opened at the switch contact 16. There fore, any interference with the safe while the locking mechanism is unlockedA will not energize the relay 34 or render effective the protective device 19. Even though the door is closed, the operation of the locking bolts 24 into locking position by turning. ofthe handle I9 will not render thedevice effective until the conrbination lock is turned into locking condition in which lug 49 prevents withdrawal of the locking bolts 24,

If, after the door has been closed and the locking bolts 24 projected into locking position, the combination lock is set to locking condition, the parts will then be in the relative positions shown in full lines in Figs. 1 and 2. With the safe fully locked, one terminal of the battery 88 will be connected by wire 81 to the relay 84 and the latter by wire 89 to the switch contact 15. The switch contact 16 is then connected by rod 51 and wires 91, 98 and 99 and the inner layer I4 of the door to the dial plate 34, and to the Ibridge 4|. The switch element 16 is also connected to the switch element 11 which is connected to the inner layer 6 of the strong box, but until a ground or connection is established to the outer plate 4 of the strong box, or to the outer plate l of the door which is electrically connected by the hinges 3 to the outer plate 4 of the box, no current can ow through wire 9| back to the battery 88. The relay 84 is thus deenergized. If a burglar attempts t0 drill the wall of the safe, the drill in passing through the outer plate 4 and thin in sulating layer 5 will engage the conducting plate or screen 6 and thus electrically connect plates 4 and 5. This co-mpletes a circuit between the switch contact 11, wire 90, screen 6, the drill, outer plate 4 and wire 9| back to the battery 88. This would deenergize the relay 84 and start an operation of the protective device 19. This operation of device 19 will continue even though the burglar may immediately remove his drill. because when relay 84 is energized, it locks itself in closed circuit position by the shunt circuit in switch member 92.

If the burglar drills the front door, so as to get at the locking mechanism, the drill in passing through the front plate I 0 and insulating layer I l will engage the screen or conducting layer I2 which is electrically connected by wire 98, the supporting member 52, and rod 51 to the Contact 16. Current will then flow from the battery 88 through the relay 84, wire 89, switch element 16, rod 51, wire 98, screen I2, outer plate I0, hinges 3. outer plate 4 and wire 9| back to the battery 88. This a'lso would set off the alarm or protective device 19, and the latter would continue active, even through the drill is immediately removed to break the initial circuit between the screen I2 and the plate I0. If instead of these drilling operations, the outer plate I0 of the door or the outer plate 4 of the box is heated by an acetylene torch to burn a hole in either' plate, the bulging of the plate and heat will destroy the thin layer of insulation or render it conductive and thus complete a circuit either between the plate 4 and layer 6 or between the plate I0 and layer I2, as disclosed and claimed in my prior copending application Ser. No. 342,027, filed June 24, 1940.

If instead of any of these operations, a burglar attempted to force or jimmy the door by insert. ing a tool between the door and the door opening of the strong box, the forcing of the door would carry the rod 51 into contact with the peripheral wall of the opening 64 and thus electrically connect rod 51 to the wall 63, which in turn is electrically connected to the outer wall 4. This completes an electrical circuit to the relay 84 and starts an operation of the protective device. If the burglar attempts to insert a chisel or tool beneath the dial 41, it forms a connection between the dial 41 and dial ring 34 and thus completes a circuit through the relay 84. If an insulated tool is inserted between the dial 41 and dial plate 34, the resulting mutilation of the dial 41 will, because dial 41 is disposed so closely to the dial plat 34, cause a contact to be made between the dial and dial plate and complete the circuit to the relay.

If, instead of any of these operations, the burglar attempts to drive the spindle 29 of the coinbination lock inwardly, it will carry one of the pins 46 into engagement with the bridge 4I and thus connect the bridge 4I to the spindle and close a circuit through the relay 84. If instead of driving the spindle 29 inwardly, the burglar attempts to pull the spindle 29 outwardly, such as by a wheel puller, it; will carry the other of the pins 46 into contact with the bridge 4I and complete the circuit through the relay 84. Thus any attempt to mutilate the safe, the door, or the locking mechanism, or to force the door by jimmying will close a circuit through relay 84 and start the protective device 19 in operation, and the latter will then continue in operation even though the original circuit through the relay which was closed by the burglar is again opened.

Referring now to the embodiment shown in Fig. 4, the apparatus is substantially the same as shown in Figs. 1 to 3, and 5 to 8, except that the rod 51 which corresponds to the rod 51 of the other embodiment, instead of operating a normally open switch into closed position when projected through the opening 64, will engage in a knife contact IOI which is secured to the inner plate or layer 6 of the safe, and a second plunger |02 is provided on a member 52a corresponding to the member 52 of the rst embodiment. This plunger |02 moves through a tube |02a aligned with an opening in the casing into the chamber 15, and engages and closes a normally open switch having contacts 16a and 11a, which correspond generally to the contacts 16 and 11 of the rst embodiment.

The plunger I 02 is electrically inert. The relay 84 is thus connected to the contact 11a and to the inner conducting layer 6 by wires I 03 and I 04 respectively, and the battery 88 is connected at one side by Wire |05 to the switch contact 16a and at its other side by wire |08 to the plate 4 Which is the outer plate of the safe. The relay switch element 92 establishes a circuit between Wires |01 and |08, which are connected respectively to the wires |06 and |04. The relay switch member 83 and the circuit controlled thereby are the same as in Fig. 3 and have the same reference numer als. The circuit through the main battery 88 and relay 84 may be established by any of the actions of a burglar as described for the rst embodiment, and will not again be described here.

It will be understood that various changes in the connections, details, materials, and arrangements of parts which have been herein described and illustrated to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims,v

I claim:

1. In a burglar resisting safe having an electrically actuated protective device associated therewith, a source of electrical current supply, a cir-- cuit connecting the latter with the protective device, and a displaceable door to said safe, the improvement which comprises a combination lock on the door including a dial and dial spindle connected to one side of said circuit and insulated from the opposite side thereof, and an inner contact element in the lock on the other side of said circuit arranged to be engaged by the spindle and to close the circuit upon endwise movement of the spindle as when punched through the lock,

2. In a burglar resisting safe of the type having an electrically actuated protective device assothe spindle arranged to engage the contact ele-v ment and close the circuit when the spindle is punched or pulled longitudinally in either direction.

3. In a burglar resisting safe of the type having a displaceable door, an electrically actuated protective device associated therewith, and a source of electrical current, the improvement which comprises a combination controlled lock for said door including a spindle, a dial mounted on said spindle, a dial plate secured against the outer face' of said door and beneath said dialand insulated from said spindle and dial, and circuit connections to said dial plate and said spindle, whereby when said connections are included in a circuit connecting said source, said protective device and said dial and dial plate, with said dial and dial plate in series in said circuit, an attempt to mutilate the combination lock which will bring said dial and dial plate into contact and complete a circuit through said protective device.

4. In a burglar resisting safe having a displaceable door, an electrically actuated protective device associated therewith, a source of electrical current, and a locking bolt carried by the door and operable into locking engagement with the safe when the door is closed, the improvement which comprises a combination lock controlling said bolt and having tumblers and a tumblersetting spindle extending outwardly through the outer face of the door and rotatably to set said tumblers to lock and unlock said bolt, and normally open contact means operable into circuit closing condition upon movement of the spindle in each endwise direction, whereby when a circuit includes in series said contact means, said source, and' said protective device, any attempt to pull the spindle or drive it inwardly will complete the circuit to said protective device.

5. In a burglar resisting safe of the type having a displaceable door, the improvement therefor which comprises a combination lock for releasably securing said door in closed position and having a dial and cooperating ring electrically insulated from each other, and circuit wires leading to said dial and ring whereby when said wires are included in series in a control circuit for an alarm device, mutilation of said lock will initiate an operation of said alarm device.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2879725 *Feb 19, 1957Mar 31, 1959Audley V ZuverBurglar proof safe
US4615280 *Nov 2, 1983Oct 7, 1986Diebold IncorporatedHigh security support and enclosure structure for electronic equipment
US4729327 *Oct 2, 1986Mar 8, 1988Demonbreun Betty JSecurity box protection means
U.S. Classification109/44, 109/42, 109/40, 340/550, 200/61.64
International ClassificationE05B65/00
Cooperative ClassificationE05B65/0082
European ClassificationE05B65/00S4