GB2267373A - Personal security alarm - Google Patents

Abstract

A personal security alarm device comprising a first, housing part (10) which is adapted to be attached to a user's wrist by a strap, thong (12) or the like, and a second, actuating part (24) which is mounted displaceably on the housing part (10) such that a predetermined displacement of the second part (24) relative to the first part (10) is arranged to trigger an audible alarm within the device. The device can be worn on either wrist, in a similar manner to a watch, and is activated simply by depressing the second part (24) relative to the housing part (10) by a sufficiently determined "knock", which causes the second part to become locked in its "down" position in which a shrill alarm signal can be continuously or periodically emitted. Outwardly, the device in addition to providing personal security, can be so designed as to appeal long-term to the fashion wearer of any age. <IMAGE>

Description

DESCRIPTION PERSONAL SECURITY ALARM The present invention relates to alarm devices of the type used for personal security and intended to be carried on, or about, the person.

Numerous personal alarm devices are in existence which range from a simple mechanical whistle to sophisticated electronic units. However, such devices are not used widely by the public because of a number of practical disadvantages associated with them.

Whistles have the disadvantage that the user must be in a position to physically blow them which, in an emergency situation, may not be possible. Available electronic devices tend to be quite large, of the order of size of a small cigarette packet, and have to be kept in a pocket or handbag, if available, when not in use. There is thus the problem of actually locating and getting hold of such devices in an emergency situation. Often, because of their size, such devices end up not being carried at all, so that their whole object is nullified.

It is an object of the present invention to provide a personal security alarm device which overcomes the practical problems and disadvantages of currently known devices in that it will be much more likely to be carried by a potential user and will be very easy to activate in most emergency situations.

In accordance with the present invention, there is provided a personal security alarm device comprising a first, housing part which is adapted to be attached to a user's wrist by a strap, thong or the like, and a second, actuating part which is mounted displaceably on the housing part such that a predetermined displacement of the second part relative to the first part is arranged to trigger an audible alarm within the device.

Preferably, the audible alarm is in the form of an alarm unit disposed within said second, actuating part. In this case, electrical connections to the alarm unit can be arranged to be "made" when said predetermined relative displacement of said first and second parts has been brought about.

The second part is preferably spring-biassed in a direction away from the first housing part whereby said relative displacement of the parts must be made against the force of a strong spring.

In one embodiment, the second part includes a projecting sleeve portion which is slidably received on a cylindrical boss on the first part (or vice versa), said spring being disposed coaxially around or within this sliding connection to bias the first and second parts apart.

Preferably, when said predetermined displacement has been brought about, it is arranged to be retained until a special action has been taken by the user to release it. For example, this can be achieved by a spring loaded pin which is driven into a bore or recess in said sleeve/boss when said predetermined relative displacement has occurred. Only upon withdrawal of the pin by the user can the firstmentioned main spring then return the second part to its initial de-activated position.

Advantageously, the second part can have a domed cover whereby to define an internal domed chamber for housing the alarm unit. The outside surface of the domed cover and the straps/thong etc., can be provided with suitable decoration to enhance the aesthetic appearance of the device, as described further hereinafter.

The present device can be worn on either wrist, in a similar manner to a watch, and is activated simply by depressing the second part relative to the casing part by a sufficiently determined "knock", which causes the second part to become locked in its "down" position in which a shrill alarm signal can be continuously or periodically emitted. Outwardly, the device in addition to providing a new level of personal security, can be so designed as to appeal long-term to the fashion wearer of any age. This is achieved by the multi-choice of casing colours and the variety of easily changeable, matching wrist straps and thongs, etc., to encourage the wearer to wear the device for all occasions and for all times.

Depending on size requirements, it may even be possible to mount a watch face in the top of the second part, whereby the device would serve the double function of time-piece and security device.

The invention is described further hereinafter, by way of example only, with reference to the accompanying drawings, wherein: Fig.1 is a diagrammatic sectional side view on the line I-I of Fig.3 of one embodiment of a personal security device in accordance with the present invention; Fig.2 is a sectional plan view on the line II-II in Fig.3; and Fig.3 is a perspective view of the device of Figs. 1 and 2 showing one possible pattern for the decorative casing top.

Referring to the drawings, the illustrated device is adapted to be worn on the user's wrist and comprises a main casing 10 having respective strap halves 12a,12b pivotally connected to two opposite sides, in the same manner as a conventional wrist watch. Thus, one strap half 12a may contain holes 14 and the outer strap half 12b may carry a buckle 16.

However, any other convenient means of fixing the strap halves together around the wearer's wrist may be used. The main casing 10 is made of a rigid material, such as metal or plastics, and has a central recess 18 which is of general cylindrical configuration in this embodiment. The central recess 18 is disposed between a pair of thicker shoulder portions 20a,20b which carry the swivel pivots 22a,22b by which the strap halves are attached to the main casing 10.

The device further comprises a domed part 24 which is adapted to be mounted displaceably relative to the main casing 10 and includes a dome base 26 of circular configuration in this embodiment and made of a rigid material, such as metal or plastics. Mounted to the dome base 26 around its upper peripheral edge (as viewed in Fig.1) is a domed decorative casing top 28. There is thus defined between the casing top 28 and the dome base 26 a domed chamber 30. Disposed within this chamber 30 and attached to the dome base around its periphery is an alarm unit 32 of a known type (in this embodiment) comprising first and second parallel alarm discs 34a,34b which cause a loud, highpitched sound to be generated when they are subjected to a high frequency voltage, applied to the discs via respective electrical wires 36a,36b.

Depending from the underside of the dome base 26, in this embodiment at a central position, is a rigid cylindrical sleeve 38 which is dimensioned so as to be slidably received over an upstanding, cylindrical casing boss 40 which is fixed rigidly to the main casing 10, within the casing recess 18. Disposed coaxially within the casing sleeve/boss coupling is a helical coil spring 42 which serves to bias apart the main casing 10 and the dome base 26. The device includes a clip means 41 for limiting the movement of the sleeve 38 in a direction away from the casing boss 40 in the assembled state so that the coaxial coupling of these components is not broken.

As shown diagrammatically in Fig.1, the two wires 36a,36b terminate at respective contacts 44a,44b which are normally separated from respective counter contacts 46a,46b mounted on a printed circuit board 48 disposed within the lower part of the recess 18 in the main casing 10. However, when the domed part 24 is moved downwardly (as viewed in Fig.1) against the force of the coil spring 42, the pairs of contacts 44a,46a and 44b,46b engage whereby to connect the alarm unit 32 to an electrical drive circuit, as described hereinafter.

The printed circuit board 48 is disposed in the recess 18 of the main casing, around the upstanding casing boss 40 and includes a number of components necessary for generating an electrical drive signal capable of actuating the alarm unit 32. In a typical case, these components would include an integrated circuit chip 50 having an oscillator function, a miniature transformer 52 for providing a high output voltage and other circuit elements such as resistors, capacitors, etc. One or more battery cells/packs 54 are also disposed within the casing recess 18, on or adjacent the circuit board 48. The underside of the casing can have an openable door (not shown) to enable the battery cell or cells to be charged or easily replaced by the owner. Alternatively, the battery cells may have to be accessed by removing the dome part 24.

Also disposed within the casing recess 18 is a means by which the domed part 24 is held in its depressed position if it has been displaced far enough into the recess. In the illustrated embodiment, this means comprises a pin 56 which is slidable in a guide bore 58 disposed in the main casing 10. The pin 56 is biassed by a coil spring 60 towards the left as viewed in Fig.l, the left-hand end of this pin normally engaging a non-recessed part of the sleeve 38.

However, if the sleeve 38 is displaced sufficiently far onto the casing boss 40, corresponding to an activated position of the device, the pin is forced by the spring 60 to enter a recessed part 64 of the sleeve 38 whereby the sleeve 38, and hence the domed part 24, is prevented from returning until the pin 56 is deliberately withdrawn by the user by pulling on a release button 66 at the opposite end of the pin.

Until the pin is withdrawn, the electrical connection of the pairs of contacts 44a,46a and 44b,46b remains and the alarm unit remains activated.

Thus, in order to activate the alarm unit 24 of the device and cause a shrill alarm signal to be emitted, the domed part 24 is caused to be displaced/ depressed towards the main casing part 10 whereby to cause the electrical connection to be made and the domed part to be locked in the down position by means of the spring-loaded pin 56. The main spring 42 is preferably selected such that a fairly determined knock on the domed part 24 is necessary in order to achieve the activated condition, thereby reducing the likelihood of inadvertent activation by day-to-day knocks to the domed part. To stop the alarm and re-set the device, all that is necessary is for the pin to be withdrawn by means of the button 66 so that the spring 42 can return the domed part 24 to its original position.

If the alarm is allowed to operate for any significant period, then a replacement battery cell(s) should be fitted to ensure that the device is ready for use when called upon.

In the device as described above, the integrated circuit and associated components are connected to the battery cell(s) permanently so that a certain, small amount of battery current is drawn continuously.

However, the small battery drain can be avoided if a switch is fitted which is also adapted to be activated by depression of the domed part 24. Such a switch could be disposed to detect displacement of the sleeve 38 or could be disposed elsewhere in the casing recess 18 for detecting displacement of the dome base 26.

In order to assist in efficient sound emanation from the alarm unit 32, the domed casing top 28 may contain holes 63 which also provide a patterned and decorative appearance.

One of the principal features which can be associated with the present device and will serve to encourage it to be worn by a potential user, is that, outwardly it can be designed to be aesthetically attractive and thereby be seen by the wearer as an individual/personal fashion accessory. This can be achieved by the application of pleasing designs to the domed part 28 and also, if desired, to the strap parts 12a,12b. Thus, for example, this can be achieved by the multi-choice of casing colours and patterns and the variety of matching (easily changeable) wrist straps and thongs etc., to encourage the wearer to use the device for all occasions and at all times.

In summary, the device is capable of serving as a fashionable, low-cost, high volume security product which can be designed so as to have significant appeal for all ages of user and which can provide a level of personal and practical security which, unlike existing personal alarms currently available, does not require to be constantly remembered, pocketed, nor extracted from a bag before it can be put into use.

Claims (10)

1. A personal security alarm device comprising a first, housing part which is adapted to be attached to a user's wrist by a strap, thong or the like, and a second, actuating part which is mounted displaceably on the housing part such that a predetermined displacement of the second part relative to the first part is arranged to trigger an audible alarm within the device.

2. An alarm device as claimed in claim 1, wherein the audible alarm is in the form of an alarm unit disposed within said second, actuating part.

3. An alarm device as claimed in claim 2, wherein electrical connections to the alarm unit are arranged to be "made" when said predetermined relative displacement of said first and second parts has been brought about.

4. An alarm device as claimed in claim 1, 2 or 3, wherein the second part is spring-biassed in a direction away from the first housing part whereby said relative displacement of the parts must be made against the force of a strong spring.

5. An alarm device as claimed in any of claims 1 to 4, wherein the second part includes a projecting sleeve portion which is slidably received on a cylindrical boss on the first part (or vice versa), said spring being disposed coaxially around or within this sliding connection to bias the first and second parts apart.

6. An alarm device as claimed in claim 4 or 5, wherein, when said predetermined displacement has been brought about, it is arranged to be retained until a special action has been taken by the user to release it.

7. An alarm device as claimed in claim 6, comprising a spring loaded pin which is driven into a bore or recess in said sleeve/boss when said predetermined relative displacement has occurred, whereby only upon withdrawal of the pin by the user can the first mentioned spring force then return the second part to its initial de-activated position.

8. An alarm device as claimed in any of claims 1 to 7, wherein the second part has a domed cover whereby to define an internal domed chamber for housing the alarm unit.

9. An alarm device as claimed in claim 8, wherein the outside surface of the domed cover and the straps/thong are provided with decoration for enhancing the aesthetic appearance of the device.

10. A personal security alarm device substantially as hereinbefore described, with reference to and as illustrated in the accompanying drawings.