GB2285878A - Personal attack alarm - Google Patents

Abstract

A personal attack alarm comprises an alarm carrying member (1) and means for producing an audible alarm consisting of one or more human screams. In one embodiment the audible alarm comprises a sequence of human screams interspersed by one or more audible siren tones. In the preferred embodiment this sequence is continuously repeated in a loop. The attack alarm has a wrist band (2) for securing the alarm carrying member about a user's wrist, the strap and alarm carrying member forming a closed loop which remains closed even when the attack alarm is being secured about or removed from the user's wrist. One end of the strap is coupled to the alarm carrying member by a safety catch (8). <IMAGE>

Description

PERSONAL ATTACK ALARM This invention relates to an alarm which may be carried on or by a person and which can be activated to summon assistance in the event of a personal attack.

Personal attack alarms are known which emit electronically produced audible tones upon activation.

However, such audible tones have become largely redundant as effective alarms as the public have become complacent towards such sounds which are now often produced by vehicle alarm systems. Many such vehicle alarms are activated erroneously or for reasons other than an attempted theft of the vehicle. Alarm sounds of this kind can therefore no longer be relied upon to attract attention in the event of a personal attack.

Personal attack alarms are also known where the alarm is worn about a person, and activated by removal of the alarm from the body of the person. Such an alarm, worn about a person's wrist, is described in, for example, US Patent Specification No. 459 1836. This alarm is activated by releasing the wrist strap of the alarm from the wearer's wrist. The disadvantage of this type of alarm is that in order to activate the alarm it must be separated from the body of the person being attacked, and could easily drop to the ground in any struggle between the attacker and his/her victim. This could allow the attacker to simply remove the victim to a location distant from the dropped alarm device. The alarm would then attract people to a place where the victim is not, serving as a diversion for the attacker.

From a first aspect the invention consists in a personal attack alarm comprising an alarm carrying member and means for producing an audible alarm in which the audible alarm comprises a human scream.

The human scream may be derived from a recording of a real human scream, or synvhesised to sound like a real human scream. Preferably the scream sounds as though it is a child's scream. It may be derived from a child's scream. This has surprisingly been found to be particularly effective at attracting attention over and above the effect of a woman's scream which surprisingly can sound too deep to cause the same psychological immediate effect as a higher pitched scream. In addition to being higher pitched than a woman's scream the child's scream may also seem a louder and more intense sound to the listener.

The alarm according to the invention has the advantage that people are likely to pay attention to the sound of the human scream. Additionally, many women or children (or men) who are attacked may be too frightened to be capable of screaming themselves and therefore can instead use the alarm to "scream" for them. Also, the human scream from the alarm may have the advantageous effect of disorientating the attacker who may wonder from where, or from whom, the scream is coming. It is also a surprising alarm sound.

Preferably, the audible alarm further comprises an audible siren tone. The audible alarm may comprise a sequence of sounds including one or more human screams followed by one or more audible siren tones.

Preferably, the audible alarm comprises a repeated sequence of sounds consisting of one or more human screams interspersed by one or more audible siren tones. The sequence is preferably continuously repeated in a loop. This combination of screams and siren tones has the advantage of being an even more effective alarm with respect to the ability of the alarm to attract attention.

Preferably there is at least one, and most preferably more than one, silence or gap in the repeated sequence of sounds.

Instead of having a repeated sequence, or a loop, of sounds there may be a library of sounds, which are played in a random or pseudonym sequence. A silence or gap may comprise a "sound" for this purpose.

Preferably, the means for producing the audible alarm comprises an annunciator which is attached to the alarm carrying member and which is adapted to produce the human scream. The annunciator may comprise a piezoelectric crystal and a generally conical member.

The conical member may be made of a plastics material.

The annunciator may effectively act as a speaker which is tuned to a single frequency.

Preferably the means for producing the audible alarm further comprises electronics adapted to send signals to the annunciator and the annunciator is preferably adapted to emit the audible alarm in response to one or more signals received from the electronics.

Preferably the electronics comprises stored signal information derived from or equivalent to a pre-recorded human scream. The frequency of the human scream is preferably substantially equal to the natural frequency of the piezoelectric crystal. The piezoelectric crystal is preferably adapted to receive signal information from the electronics which may cause the crystal to vibrate at a frequency which is such as to cause the annunciator to produce either the human scream or the audible siren tone.

The alarm may be activated by moving an activation member, for example a push button located on the alarm carrying member. It may be possible to test the alarm by activating a test member (for example by semi-depressing or tapping the push button which may cause the attack alarm to emit a brief screaming noise). Preferably the alarm may be fully activated by activating the same test member, most preferably by placing it in a locked condition which causes the audible alarm to be activated. Once it has been activated the alarm will preferably continue to sound until the batteries expire or until it is reset by means of a reset button (if provided), preferably located on the underside of the alarm mounting member.

Preferably the reset button (or other member) can only be operated by means of a fine tipped implement, such as a pencil point. Thus an attacker cannot stop the alarm sounding without locating and operating the reset button.

From a second aspect the invention consists in a personal attack alarm comprising an alarm carrying member and means for producing an audible alarm and further comprising a strap for use in securing the alarm carrying member about a user, the arrangement being such that the strap and the alarm carrying member together comprise a closed loop which remains closed even when the attack alarm is being secured about, or being removed from the user.

The strap may be formed from a band, wire, chain, rope or any other suitable means for forming a strap.

Preferably, the strap comprises a band formed from injection moulded plastics material.

The alarm mounting member may comprise a housing.

Preferably, the attack alarm is adapted to be secured about the user's wrist. One end of the strap may be coupled to the alarm carrying member by means of a hinge. The other end of the strap may be coupled to the alarm carrying member by a coupling means which enables the attack alarm to be secured about the user's wrist in such a way that the attack alarm cannot be easily removed from the user. The coupling means preferably comprises a safety lock having operative and inoperative conditions, its arrangement being such that when the safety lock is in its operative condition the attack alarm cannot be removed from the user and with the safety lock in its inoperative condition the attack alarm can be removed from the user.

The safety lock may comprise a retaining member attached to the strap and having a latch component which registers with a notch in the alarm carrying member when the lock is in its operative condition, and does not register with the notch in the alarm carrying member when the lock is in its inoperative condition.

With the lock in its operative condition, the retaining member may be either partially or fully inserted within the alarm carrying member. The retaining member may be moved in order to change the lock from its operative to its inoperative condition. Although the loop formed by the strap and the alarm carrying member may be extended when the safety lock is in its inoperative condition, the retaining member remains partially inserted within the alarm carrying member such that the loop is still a closed loop which must be slid over the user's hand in order to remove it from the user's wrist.

The alarm is therefore not easily removable from the user's wrist. In order to remove the alarm in a struggle between an attacker and the user, the attacker would need to operate the safety lock to its inoperative condition and then slide the alarm over the user's hand. Such an operation would be fiddly and time consuming.

According to a third aspect the invention consists in a method of emitting an audible alarm for a personal attack alarm in which a sequence of sounds comprising one or more human screams is produced.

Preferably the human screams are interspersed by one or more audible siren tones.

Preferably the human screams and siren tones are repeated in a loop sequence.

There now follows a detailed description of the invention to be read with reference to the accompanying drawings of which: Figure 1 is a plan view of a personal attack alarm according to the invention; Figure 2 is a side view of the attack alarm; Figure 3 is a sectional side view of the attack alarm, including a wrist band, taken along the line B-B of Figure 1; Figure 4 is a partial sectional view of an alarm carrying member of the attack alarm, taken along the line C-C of Figure 3; Figure 5 is an end view of the attack alarm; Figure 6 is a sectional end view of the attack alarm, not showing the contents of the alarm carrying member, taken along the line D-D of Figure 3, and Figure 7 is a partial end view of an end of the attack alarm containing a hinge.

Referring to Figures 1 and 2, a personal attack alarm comprises an alarm mounting member in the form of a housing 1, and a wrist band 2. The housing 1 has two ends 3, 4 and the wrist band 2 has two ends 5, 6. One end 3 of the housing 1 is attached to one end 5 of the wrist band 2 by means of a hinge 7. The other end 4 of the housing 1 is attached to the other end 6 of the wrist band 2 by coupling means defined by a safety lock in the form of a catch 8. The housing 1 and wrist band 2 form a closed loop through which a person's wrist may be inserted, thus enabling the attack alarm to be worn about the person's wrist. The housing and/or strap may be of a gold colour, or other decorative colour, so that the alarm looks as if it is an item of jewellery, and does not look immediately like an alarm.

The housing 1 is shown in detail in Figures 1 to 6 and is a hollow member, having a front wall 9 and a rear wall 10, which in plan view is a generally elliptically shaped member with the two opposing tips of the ellipse which lie on the major axis of the ellipse having been effectively cut off, as shown in Figure 1. The two ends 3, 4 of the housing 1 are each curved towards the respective wrist band end 5, 6 in order to form the closed loop, as shown in Figure 2.

Inside the housing there is a chamber 11, as shown in Figure 3, which contains one or more battery cells 12, a piezoelectric crystal 13, electronics comprising a printed circuit board (PCB) 14 and a generally conical member comprising a Mylar (Registered Trade Mark) cone 15. The housing 1 is formed with a removable portion 16b in its rear wall 10 which may be removed to gain access to the chamber 11 in order to insert or replace the battery cells 12. The housing 1 further comprises a sound baffle 16 located on the upper wall 9 of the housing 1, directly above the Mylar cone 15 and covering a hole or gap 17 in the front wall 9 which is also located directly above the Mylar cone 15.The cone 15 is located directly above the piezoelectric crystal 13 such that the central axis of the cone lies substantially perpendicular to the crystal 13 and with the circumferential edge 18 of the wide end of the cone being glued to the front wall 9 of the housing 1 and the tip 19 of the cone 15 being attached to an upper surface 20 of the piezoelectronic crystal 13 such that when the crystal 13 vibrates it causes the Mylar cone 15 to vibrate which, in turn, produces sound. The Mylar cone 15 and the piezoelectronic crystal 13 together comprise an annunciator, with the cone 15, the front wall 9 of the housing 1, and the sound baffle 16 together forming an acoustic chamber 21 which amplifies sound produced by the annunciator. The sound leaves the chamber 21 through gaps 17b located between edges of the baffle 16 and the front wall 9 of the housing 1 (see Figures 5 and 6).

The PCB is located directly above the crystal 13, within the housing 1, such that it lies in a plane substantially parallel to the crystal 13 and largely underneath the walls of the Mylar cone 15. The PCB has an elongate slot 23 extending, inwardly from one of its edges, towards the centre of the PCB, shown in Figure 4, which enables the PCB to be slotted around the tip 19 of the cone 15, as shown in Figure 3. The PCB comprises all or most of the electronics of the attack alarm and is electrically connected to the piezoelectronic crystal 13 to enable it to send electrical signals to the crystal 13 which cause the crystal to vibrate. The PCB further comprises one or more chips containing stored signal information including signal information derived from a pre-recorded human scream.This pre-recorded scream originates from two studio recordings of a human scream, each of these recordings having been "cleaned up" by removing spurious frequencies, to leave a main "scream" frequency. The two recordings are split in different ways to make up the pre-recorded scream which is stored as signal information in a chip on the PCB 14. The frequency of this scream is substantially equal to the natural frequency of the piezoelectric crystal 13, which may be substantially 2.5kHz. When this scream signal information is sent to the piezoelectronic crystal 13 by the PCB 14, it causes the crystal to vibrate at the scream frequency in order to cause the annunciator to produce the scream.

Additionally, one of the PCB chips contains stored signal information which, when sent to the piezoelectronic crystal, causes the annunciator to produce an audible siren tone at a different frequency to the scream frequency. The PCB may be capable of boosting the output power of the battery cells 12 to approximately 60 volts.

One of the PCB chips holds stored information relating to the actual form of the emitted audible alarm. The audible alarm comprises a repeated sequence of sounds, the sequence consisting of human screams interspersed by at least one audible siren tone. This chip contains signal information which, when sent to the piezoelectronic crystal 13, dictates the number and length of the various constituent sounds of the emitted audible alarm, which comprises: one long scream lasting approximately 4 seconds, followed by one siren tone lasting approximately 3 seconds, followed by a short scream lasting approximately 1 second, followed by a silent gap of approximately 0.5 second, followed by a further short scream of approximately 0.5 seconds, followed by a further silent gap of approximately 0.5 seconds.The final silent gap may be followed by a further siren tone which may last for approximately 2 seconds. There may or may not then be a further silent gap of about 0.5 seconds before the sequence is repeated.

Activation of the attack alarm causes the PCB 14 to send a series of signals to the piezoelectronic crystal 13 which causes the annunciator to produce the above sequence of sounds. This sound sequence forms a basic building block of the emitted audible alarm and lasts for approximately 10 to 12 seconds in total. This sound sequence building block is effectively held in a repeating loop within the electronics of the PCB 14 so that when the attack alarm is activated this block is repeated continuously until either the alarm battery cells 12 expire or until the attack alarm is reset.

The housing 1, as shown in Figures 3 and 5, carries a push button 22 which is mounted in the front wall 9 of the housing 1, to one side of the baffle 16, such that the button 22 partially extends into the chamber 11. Inside the chamber 11 is a switch mechanism (not shown) which has an operative and an inoperative condition. Before activation of the alarm, the switch is in its inoperative condition. The alarm remains unactivated until the switch is operated to its operative condition. The alarm may be tested by tapping the push button 22 briefly, or semi-depressing it, which causes the button to operate the switch to its operative condition for a brief length of time which, in turn, causes the alarm to emit a short audible scream burst if the battery cells 12 are still properly charged.The alarm is fully activated by depressing the push button 22 into the chamber 11 of the housing 1 until it locks into its operative condition which, in turn, locks the switch in its operative condition, causing activation of the audible alarm. A reset button 24 is located in the rear wall 10 of the housing 1. The reset button 24 may only be accessed from the rear of the housing 1 and may only be operated by a fine tipped implement such as a pencil point.

Operation of the reset button allows the alarm to be reset after it has been activated.

The wrist band 2 has inner and outer surfaces 31, 32. In normal use, the attack alarm would be secured about the person's wrist by means of the safety catch 8, shown in cross-section in Figure 3. The catch 8 comprises a spring member which is a generally elongate strip having one end integrally attached to the end 6 of the wrist band 2, proximate to the inner surface 31 of the wrist band 2, and having one end free. The strip is bent along a line which lies substantially half way along, and perpendicular to, its length to create a fold 33 in the strip such that the strap is doubled back on itself to form two overlapping leaves 29, 30. The free end of the strip comprises a protruberance 25 which extends at substantially a right angle to the fold 33 in the strip, away from the end of the strip which is integrally attached to the wrist band 8.The spring member further comprises a small, latch protruberance 26 located on the same leaf 30 which has the protruberance 25 and extending in the same direction as the protruberance 25. The end 4 of the housing 1 comprises a gap between the front and rear walls 9, 10 through which the fold 33 of the spring member extends such that the two leaves 29, 30 of the folded spring member extend into the chamber 11 of the housing 1, as shown in Figure 3.

The safety catch 8 has an operative and an inoperative condition. With the safety catch 8 in its operative condition the two leaves 29,30 are fully inserted within the chamber 11, through the gap in end 4 of the housing 1 such that the housing 1 and the wrist band 2 form a closed loop. The protruberance 25 is squeezed between the portion of the housing end 4 comprising the front wall 9 of the housing, and the end 6 of the wrist band 2, with the resilient force of the spring tending to push the protruberance 25 on the free end of the strip outwardly between the wrist band end 6 and the housing end 4 so that it protrudes past the outer surface 32 of the wrist band 2, and the front wall 9 of the housing 1.The latch protruberance 26 is pushed, by the resilient force of the spring member, into a locating notch in the front wall 9 of the housing 1 so that the housing end 4 and the wrist band end 6 cannot be separated. With the catch 8 in its operative condition the closed loop formed by the housing 1 and the wrist band 2 is not sufficiently large to allow the attack alarm to be slipped over the wearer's hand.

The spring member may be moved to its inoperative condition by depressing the protruberance 25 to compress the two leaves 29, 30 together in order to retract the latch protruberance 26 from the locating notch. This enables the housing 1 to be pivoted slightly about the hinge 7 in order to slide the housing end 4 away from the wrist band end 6.

(Alternatively or additionally the strap 2 may be flexible, for example comprising plastics material.) However, the two ends 4, 6 are prevented from separating entirely by at least one projection 27 attached to leaf 30 of the spring member and located near the fold 33 in the strip, which contacts with an abutment 28 projecting into the chamber 11 from the front wall 9 of the housing 1. The closed loop formed by the housing 1 and the wrist band 2 therefore remains a closed loop at all times. However the circumference of the loop may be extended, while the catch 8 is in its inoperative condition, by an amount which enables the attack alarm to be slid over the hand of the wearer in order to remove it from the wearer.

The housing 1 and the wrist band 2 is formed from injection moulded plastics material. In an alternative embodiment they are integrally moulded. In a further embodiment the wrist band is formed of a flexible material.

Claims (27)

1. A personal attack alarm comprising an alarm carrying member and means for producing an audible alarm in which the audible alarm comprises a human scream.

2. A personal attack alarm according to claim 1, in which the human scream is derived from a recording of a real human scream.

3. A personal attack alarm according to claim 1, in which the human scream is synthesised to sound like a real human scream.

4. A personal attack alarm according to any preceding claim, in which the human scream is a child's scream.

5. A personal attack alarm according to any preceding claim, in which the audible alarm further comprises an audible siren tone.

6. A personal attack alarm according to claim 5, in which the audible alarm comprises a repeated sequence of sounds consisting of human screams interspersed by one or more audible siren tones.

7. A personal attack alarm according to claim 6, in which the sequence of sounds is repeated in a continuous loop.

8. A personal attack alarm according to claim 6 or claim 7, in which the repeated sequence of sounds comprises at least one silence or gap.

9. A personal attack alarm according to any preceding claim, in which the means for producing the audible alarm comprises an annunciator which is attached to the alarm carrying member and which is adapted to produce, in use, the human scream.

10. A personal attack alarm according to claim 9, in which the annunciator comprises a piezoelectric crystal and a generally conical member.

11. A personal attack alarm according to any preceding claim, in which the alarm carrying member comprises an acoustic chamber and a sound baffle.

12. A personal attack alarm according to any one of claims 9 to 11, in which the means for producing the audible alarm further comprises electronic circuitry adapted to send signals to the annunciator which is adapted to emit the audible alarm in response to one or more signals received from the electronic circuitry.

13. A personal attack alarm according to claim 12, in which the electronic circuitry comprises stored signal information derived from or equivalent to a pre-recorded human scream.

14. A personal attack alarm according to any one of claims 10 to 13, in which the frequency of the human scream is substantially equal to the natural frequency of the piezoelectric crystal.

15. A personal attack alarm according to claim 14, in which the piezoelectric crystal is adapted to receive a signal from the electronic circuitry in response to which signal the crystal vibrates at its natural frequency and the annunciator produces the human scream.

16. A personal attack alarm according to claim 14 as dependent from claim 12, in which the piezoelectric crystal is adapted to receive a signal from the electronic circuitry in response to which signal the crystal vibrates at a frequency which is such that the annunciator produces the audible siren tone.

17. A personal attack alarm according to any preceding claim, further comprising a moveable activation member located on the alarm carrying member.

18. A personal attack alarm according to claim 1, further comprising a strap for use in securing the alarm carrying member about a user, the arrangement being such that the strap and the alarm carrying member together comprise a closed loop which remains closed while the attack alarm is being secured about, or being removed from, the user.

19. A personal attack alarm according to claim 18, in which the strap comprises a band adapted to be secured about the user's wrist.

20. A personal attack alarm according to claim 18 or claim 19, in which one end of the strap is coupled to the alarm carrying member by a coupling means comprising a safety lock having operative and inoperative conditions.

21. A personal attack alarm according to claim 20, in which the safety lock comprises a retaining member attached to the strap, the retaining member having a latch component which registers with a notch in the alarm carrying member when the lock is in its operative condition.

22. A personal attack alarm according to claim 21, in which the alarm mounting member comprises a housing.

23. A personal attack alarm according to claim 22, in which the retaining member is at least partially inserted within the housing when the safety lock is in its operative condition.

24. A method of emitting an audible alarm for a personal attack alarm in which a sequence of sounds comprising one or more human screams is produced.

25. A method according to claim 24, comprising interspersing human screams with one or more audible siren tones.

26. A method according to claim 25, comprising repeating human screams and siren tones in a loop sequence.

27. A personal attack alarm substantially as described herein and with reference to the accompanying drawings.