Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS2927311 A
Publication typeGrant
Publication date1 Mar 1960
Filing date10 Dec 1957
Priority date10 Dec 1957
Publication numberUS 2927311 A, US 2927311A, US-A-2927311, US2927311 A, US2927311A
InventorsPeter Donaldson
Original AssigneeSecurity Products Mfg Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Portable containers provided with theft alarm devices
US 2927311 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

March 1, 1960 P. DONALDSON 2,927,311




PORTABLE CONTAINERS PROVIDED WITH THEFT ALARM DEVICES Filed Dec. 10, 1957 3 Sheets-Sheet 3 INVENTOR PETER bounLosoN aLLL/s ATTORN EYS United States Patent PORTABLE CONTAINERS PROVIDED WITH THEFT ALARM DEVICES Peter Donaldson, Staines, England, assignor to Security Products Manufacturing Company Limited, London, England, a British company Application December 10, 1957, Serial No. 701,899 7 Claims. (Cl. 340283) This invention relates to portable containers such as bags, boxes or cases provided with theft alarm devices. Such containers are used, for instance, by bank messengers, wage clerks and others who are required to carry money or other valuables.

Portable containers provided with electrical theft alarm devices triggered off by release of a switch in the handle of the container are already known. Such devices are not without their drawbacks since it is easy for the person carrying the bag to release the switch inadvertently and so set off the alarm. Moreover, if the thief is aware that there is an alarm switch in the handle he may be able to seize the container in such a manner as to prevent release of the switch. Portable containers provided with electrical or mechanical alarm devices have been proposed in which a trigger string or wire isattached to the person carrying the container so that if the container is snatched from him the string or wire will be pulled and the alarm device actuated. Here again there are disadvantages since accidental triggering is easy, and if the thief is aware of the mechanism he may first sever the string or wire.

The present invention provides a portable container equipped with a theft alarm device which is not subject to the aforementioned disadvantages.

A portable container according to the present invention is equipped with a theft alarm device which is actuated on the interruption of an electric triggering circuit through which a current normally flows, and is adapted to be attached to the person carrying it by means of a frangible conductor forming part of the triggering circuit.

Thus, if a thief should snatch the container from the person carrying it, the frangible conductor will break, thereby interrupting the triggering circuit and actuating the alarm device. Inadvertent actuation of the alarm device by the person carrying the container is less likely than with an arrangement which relies on the person continually holding a switch against release, and if the thief should deliberately sever the frangible conductor he will interrupt the triggering circuit and actuate the alarm device.

The alarm device may take any suitable form, for instance it may be an audible warning device such as an electric horn or siren, or it may be a device which hampers the thief, such as a tear gas bomb.

Preferably, the container includes a lockable compartment containing a switch controlling the alarm device and the triggering circuit, the said switch having an off position in which no current flows and the alarm device is inoperative, and an on position in which a current flows through the triggering circuit. This compartment may be the same compartment as that which accommodates the valuables.

Preferably, the alarm device and the means for actuating it are contained in a tamper-proof compartment.

In one form of the invention the frangible conductor 2,927,311 Patented Mar. 1, 1960 is adapted to be attached to the person who carries the container by a wrist strap, the conductor encircling the wrist when the strap is in place so that an attempt to remove the wrist strap will interrupt the triggering circuit and actuate the alarm device.

The triggering circuit preferably includes the winding of a relay which when energised by the current flowing through the triggering circuit holds open contacts in an actuating circuit of the alarm device and when de-energised by interruption of the triggering circuit permits the said contacts to close, thereby closing the actuating circuit of the alarm device.

- Preferably, de-energisation of the relay also opens contacts in the triggering circuit so that the 'alarm device cannot be stopped by re-connectingthe broken frangible conductor.

The invention may be performed in various ways and one particular form of container embodying the invention, namely a wages bag, will now be described by way of example with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of the bag being carried;

Figure 2 is a view of the wrist strap in its open position;

Figure 3 is a sectional elevation of an inner strong box of the bag with the electrical connections omitted; and Figures 4 to 7 are circuit diagrams showing respectively the connection'with the switch in the OE position, in an intermediate position and in the on position, and also when the frangible conductor has been broken. In Figures 5 to 7 the parts of the circuit through which a current is flowing are shown by heavy lines.

The bag shown in the drawing comprises an outer case 10 of leather, plastic or other suitable material, having a flap 11 secured by straps 12 and a lock 13. A carrying handle 14 is attached to the flap 11.

The case 10 contains a steel strong box 15 (shown in section in Figure 3) which has a hinged lid 16 provided with a stout lock 17. The box is divided by a horizontal partition 19 into an upper compartment 20 and a lower compartment 21. The upper compartment 20 contains a switch knob 22 and an indicator lamp lens 23, and also accommodates the money when the bag is in use.

The lower compartment contains an electric battery 24 of substantial capacity, and an electric horn or siren or other alarm device 25. The bottom of the box 15 may be perforated at 26 beneath the alarm device 25, and the bottom of the case 10 may be similarly perforated, in order that the noise emitted by the alarm device shall not be muflied, but the perforations should be such that they do not expose any vulnerable part of the alarm device. The lower compartment 21 also contains an upright bracket 27 which supports an electric relay 28 and an indicator lamp 29 disposed immediately below the lens 23. Switch mechanism 30 controlled by the knob 22 is also disposed in the lower compartment 21 and may be mounted on the bracket 27. The parts 24, 25, 28, 29 and 30 are connected by electric wiring in a manner to be described, which Wiring has been omitted from Figure 3 for clarity.

Part of the said wiring passes out through the wall of the box 15 and extends through a thong 31 provided with a readily-detachable plug and socket connector 32,

33 to a wrist band 34 which is shown in more detail in Figure 2.

The wrist band 34 includes conventional straps 3S and buckles 36 by which it can be fastened snugly round the wrist, and it also includes a tongue 37 provided at its end with a snap fastener socket 38 which is adapted to be snapped on to a stud 39 near the buckles 36. The

of therswitch section 30a. he-gswitch section j30c 'is-also connected by a wire 54 with one contact of the socket =plug 33 is of the c oaxial' type having a central conducting pin insulated from .a conducting sleeve, these parts being connected respectively to conductors and embedded in the thong'31 and the wrist strap 34 and leading to the snap fastener socket 38 and thestud 39 respectively. Thus,

when the strap is fitted around the wrist and the snap fastener 38,39 secured, the conductors --40 and 41 are connected together. 'If, however, thewrist strap should be removed by releasing the snap fastener 38, 39, contact between the conductors 40 and 41 will 7 be broken.

In the part of the thong 31attached'to thei'bag'there are likewise two conductors connected respectively to .acentral socket portion and an. outer sleeve portion .46:to .a terminal 47 of a third section sec of the switch. The other pole of the battery 24 isconnected by a .wire

.48 to a terminal 49of the switch section 30c. Also .con-

nected to the terminal 49 is a wire 50 leading'to the movable contact of a pair of c'ontactsSl of the relay 28.

The corresponding ,fixed contact is connected to the actuating winding 52 'of the alarm device 25, theother end of this winding being connected .to a contact 53 The :terminal '49 of 32.. The other contact 'of the socket 32 is connected .ito the moving contact of another contact pair,55 of the relay. The relay contacts'are so arranged that the contacts 55 are-closed when' the contacts-l are open, and The fixed contact of the contact pair 55 is vice versa. connected to ,a junction 56; From this vjunction one branch leads through the winding ,57 ofithe relay, 28 to a terminal 58 of the switch section:30b,' while the other branch 59 is connected to ,a terminal .60 of ;the :switch section 30c.

,The bagis used'and operated follows." Assume that the container is being usedby a wages clerk for drawing wages from-a bank. He opens the case and g the strong box on the bank counter. The switch :knob

22 will now be in the off positionyand since the terminals 43, 45, 47 and 49 are isolated within the switch 30; no cnrrent is flowing through any part ofthe circuit.

3 Hethen puts on the wrist strap, ifitis not on already,

making sure that the snap fastener38, 39 is properly connected. He also insertsthe plug '33 into the socket 32, thereby closing the triggering circuit at this point.

Current does not yet flow through the-triggering circuit, however, since the relay contacts 55. are open, and moreover no connections have yet been established 'to' the battery through the switch 30.

He then turns the switch knob 22 to the on position.

In moving from the off position to the *on. 'posi-.

tion the switch 30 passes'through an intermediate posi tion in which connections are established as shown in Figure 5. In this intermediate position the terminals 45 and 58' of the switch section 30b are'connected together, and the terminals 49 and 6,6 of the switch section 30c are connected together. the battery 24 through "thewlfe 42, the'terminal 43, the wire 44, the link between the terminals .45 and 58, the energising winding 57 of the relay 23, the junction 56, the wire 59, the link between the terminals 60 and 49, and the wire 48 back to the battery. The relay 28 is thus energised, opening the contacts 51 and closing the 'contacts 55.. Opening the contacts 51 introduces a furtherbreak into the alarm circuit which is already broken at the isolated switch terminal 53. Closing the contacts 55 causes a current'to flow through the triggering circuit A circuit is thusestablished from from the battery 24, the wire 42, the terminal 43, the

'wire'44, the link between the terminals ,45 and 58, the relay winding 57, the junction 56, the now closed relay contacts 55, the, plug and socket connector 32, 33, the

.snap fastener connection 38, 39, the wire 54, the terminal 49, and the wire '48 back to the battery.

The second part of thernovcnient of the switch towards the on position connects theterminals43and 53 of the switch section a, breaksthe connection between the terminals 49 and .60 of the switch section 300, and connectsthe terminals 47 and 49 of this switchsection. 'A circuit is thusestablished from'the terminal 'to the terminal 47 through the indicator lamp '29 and the resistor 4o, whereby theindicator lamp lights to indicate that the alarm device is now set. The clerk puts the money in the upper'compartment '20 of the box, closes the lid 16 and locks it, and closes the flap 11.'

7 When he wishes to remove the money he merely reverses the seriesjofloperations described and turns the switch back to the off position. This restores the :circuit to the condition shown inFigure 4 and enables him to disconnect the plug and socket connector 32,133 and rernove the wrist strap. without triggering ofithe alarm :thong:31 otherwise severed, or the wrist strap. removed,


However, should the. bag hssnatchedfrom him :orthe :the triggering circultwill beibroken as shown in Figure '7. This de-energises the relay: winding 57 so that the .contact's'51 are closed andthe contacts opened. As soon as the contacts 51.are closed'a circuit is established from the battery 24'through:.the 'wire'42, the link between the terminals 43 and 53, the actuatingv winding 52 of the'alarm device, the'closed contacts 51, the wire 50, the terminal 49 and'the wire 48'back tothe battery. The alarm V deviceqtherefore operates and will continue to operate until either the box is unlocked and opened and the switch'turned off, or until the battery runs 'down. The alarm device cannot be stopped byre-establishing contact between the two parts of'the socket 32, since the relay contacts 55 in the triggering circuit are open.

What I claim as my invention and desire to secureby Letters Patent is: c

1. A portable container, an alarm device disposed in said container, electricalactuating means for said alarm device, a sourceof electric current, anorinally interrupted electric actuating circuitjncluding said actuating means, and said source of electric-current such, that closure "of said actuating circuit sets off said alarm device,

a normallynclosed ,-.electric triggering circuit contact means for closing said actuating circuit on interruption of said triggering circuit, a Wrist strap, a conductor in said wrist strap terminating in separable contacts adapted to be connected-together when said wrist strap is in'a closed condition to complete a conductive loop, and frangible conductors connecting :said container to said wrist strap, said conductiveloop in said wrist strap and said frangible conductors forming part of said triggering circuit. r

2. A portable container according to claim l'in which said frangibleconductors include a double contact-plug and socket connector, said plugbeing a push fit in-said socket and separable from said socket by a direct pull.

,3. A portable container'according to claim 1 comprising walls and an'openable coverdefining a compartfromsaid lockablecompartmenhsaid alarm device, said source of electric current and said actuating circuit being 7. A portable container according to claim 1, in which accommodated in said second compartment. said alarm device gives an audible signal on closure of 5. A portable container according to claim 1, in which said actuating circuit.

saidtriggering circuit includes the Winding ofa relay Refec'se "lie th 111' atent which 18 energised by the current normally flowmg 5 i W3 5 b E m efile of p through said triggering circuit, and relay contacts in said UNETED STATES PATENTS actuating circuit which are held open when Said relay 1,747,194 Thomas Feb. 18, 1930 Winding is energised and which close when said relay 2 3 999 Poulson r Aug 17 1954 Winding is de-energised. V n a 6. A portable container according to claim 5, in which 10 FOREIGN PATENTS said triggering circuit includes relay contacts adapted to ,7 r at i n MIL 1934 open when said relay Winding is tie-energised. 1,011,667 France June 25, 1952 UNITED STATES PATENT OFFICE CERTIFICATE 0F CORRECTION March 1 1960 Patent Noan2 92'i 3ll Peter Donaldson It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below, a K

In the heading to the printed specification between lines 10 and 11 thereof insert Claims priority application Great Britain December l9 1956 Signed and sealed this 29th day of November 1960a (SEAL) Atcest:

KARL AALINE ROBERT c. WATSON Commissioner of Patents vAtteslzing Officer

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1747194 *12 Jun 192218 Feb 1930Le Roy ThomasTheft protection for vehicles
US2686909 *28 Dec 194917 Aug 1954Certified Burglar Alarm SystemElectric burglar alarm system
FR1011667A * Title not available
GB404727A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3253270 *2 Aug 196324 May 1966Downer FrankTheft alarm for shoplift prevention
US3530451 *20 Jan 196722 Sep 1970Security Systems IncHolster radio alarm
US3815118 *27 Dec 19714 Jun 1974Donald L McHandbag with a theft alarm and protection device
US3832705 *14 Jun 197327 Aug 1974King BAlarm device
US3851326 *17 Apr 197226 Nov 1974V CostaPurse alarm
US3938124 *23 May 197410 Feb 1976Salient Electronics, Inc.Alarm system sensing device
US4000488 *19 Apr 197428 Dec 1976Bernard EphraimLabel alarm system
US4155079 *2 Nov 197615 May 1979Hui-Lang ShiehTheft-proof suitcase
US4204202 *13 Jul 197820 May 1980Pai George CSecurity attache case with automatic alarm system
US4587517 *28 Jan 19856 May 1986At&T Technologies, Inc.Intrusion sensing device
US4881672 *3 May 198821 Nov 1989Olivia GustafsonSafety attachment pruse hook
US4908607 *23 Feb 198913 Mar 1990Yannotti Julian JAnti-pickpocket alarm
US5164706 *11 Sep 199117 Nov 1992Yoky ChenBriefcase/handbag alarm device
US5345221 *2 Jun 19926 Sep 1994John Michael PonsArm alarm system
U.S. Classification340/571
International ClassificationG08B15/00, A45C13/24, A45C13/00
Cooperative ClassificationA45C13/24, G08B15/00
European ClassificationA45C13/24, G08B15/00