Abstract:
A battery powered personal security device is designed to be worn on the wrist of a wearer like a bracelet. The device includes an electrical circuit adapted to generate a discharge voltage of around 1500 volts sufficient to deter an attacker but not cause tissue damage. There are two adjacent electrodes that protrude through the sloped front face of the device. The sloped front face is adapted to contact facial skin and when the electrodes are in simultaneous contact with the skin of the attacker the device discharges.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of provisional patent application No. 61015351 filed in the United States Patent and Trademark Office on Dec. 20, 2007. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention pertains to security devices that are worn on the person and in particular to a personal security bracelet that is adapted to discharge electricity onto the skin of an attacking person at a voltage sufficiently high so as to deter an attack but not to cause tissue damage. 
       BACKGROUND OF THE INVENTION 
       [0003]    Security devices that discharge electricity are well known. Examples include the TASER™ family of Electronic Control Devices (ECD) manufactured by TASER International. The TASER™ C2 is a self-defense ECD using propelled wires or direct contact to conduct electrical energy onto the body of an attacker. The electrical discharge can be as high as 50,000 volts in order to affect the sensory and motor functions of the nervous system of a potential attacker. The TASER C2 uses a replaceable cartridge, containing compressed nitrogen, to deploy two small probes that are attached to the TASER C2 by insulated conductive wires with a maximum length of 15 feet (4.5 meters). The probes can penetrate up to two cumulative inches of clothing. 
         [0004]    This type of stand-off device works best when the individual has sufficient time to deploy it from a purse or holster. In other situations, such as when an individual is ambushed without warning, the TASER-type device is not effective as there is no time to deploy, aim and fire the device. 
         [0005]    Hand-held TASER-type devices are also available for personal security. These devices are often kept in a purse or similar container. The obvious disadvantage with this type of device is that if a person is attacked without warning then it is almost impossible to retrieve the device from its storage location in order to use it against the attacker. 
         [0006]    Therefore, there is a continued need for a close-in deterrent device that is capable to delivering a sufficient electrical shock to an attacker and is worn on the body so that pre-deployment is not necessary. 
       SUMMARY OF THE INVENTION 
       [0007]    The shortcomings of the prior art are resolved by the provision of a personal security device to be worn securely on a person comprising: a body having a sloped front face having an angle of approximately 60 degrees and a vertical rear face, means for power storage in electrical communication the said body, means for generating a discharge voltage; and, means for discharging the discharge voltage onto the skin of an attacker sufficient to deter the attacker without tissue damage. The invention is adapted to be worn as a bracelet on the wrist of a person and is secured by an adjustable strap. The means for discharging the discharge voltage comprises a first exposed electrode and an adjacent second exposed electrode adapted for communicating the discharge voltage onto the skin of the attacker. The electrodes protrude from the sloped front face of the body. When the electrodes are in simultaneous contact with the skin of the attacker the discharge voltage will discharge. The electrodes are in contact with a voltage storage capacitor which is in contact with the high voltage side of a transformer housed within the body of the invention. The invention is powered by at least one DC battery and typically an AA or MA sized battery although other sizes can be used. The discharge voltage is in the range of 1500 volts. 
         [0008]    In another example of the invention there is provided a “dead man switch” which must be depressed in order for the device to discharge. This prevents a person from being stuck on the discharging electrodes. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a schematic of the electrical circuit of one example of the invention. 
           [0010]      FIG. 2  is a front view of one example of the invention placed on the wrist of a wearer. 
           [0011]      FIG. 3  is a top view of one example of the invention. 
           [0012]      FIG. 4  is a rear view of one example of the invention. 
           [0013]      FIG. 5  is a side view of one example of the invention. 
           [0014]      FIG. 6  is a schematic of the electrical circuit of another example of the invention. 
       
    
    
     DESCRIPTION OF THE INVENTION 
       [0015]    The drawings enclosed herein illustrate at least one example of the invention which is a personal security bracelet. The following descriptions and the figures, to which it refers, are provided for the purpose of describing examples and specific embodiments of the invention only and are not intended to exhaustively describe all possible examples and embodiments of the invention. Many specific implementations of the personal security bracelet described herein that a person skilled in the art would see as novel and inventive. 
         [0016]    The invention is intended to be used as a personal security device for people who feel somewhat uncomfortable in their immediate surroundings and require some extra security and protection. The invention provides this extra security and protection inexpensively and effectively. Some applications of the invention include: persons walking late at night in the city or wilderness, to repel an unwanted intrusion of personal space by people or animals, persons walking in areas of known high crime; to defend against animal/dog attack, jogging alone or walking alone. The invention is well adapted for use by individual citizens as well as by law enforcement personnel. 
         [0017]    Referring now to  FIG. 1  and  FIG. 2 , there is shown a schematic of the circuit of the invention  10 . On the low voltage side of the circuit there is at least one battery but generally two batteries stored in casings  22  and  24 . These can be AA or AAA sized batteries but other even smaller high voltage batteries can be used such a mini 12 volt batteries. The batteries are in series with an on/off switch  20  and connected to LED  26 . LED  26  is on when the device is switched on and fully charged with a discharge voltage. The circuit also includes transistor  32  and the low voltage coil  35  of transformer  34 . On the high voltage side of the circuit there is the high voltage coil  37  of transformer  34  in series with diode  36  and connected to the discharge switch  21 , the capacitor  38  and the discharge electrodes  14  and  15 . A person skilled in the art will realize that this circuit is but one example of a discharge voltage generating circuit and that other circuits can be used to generate and safely store a discharge voltage of desired magnitude. 
         [0018]    Referring to  FIG. 2 , there is shown a front view schematic drawing of one example of the invention  10  placed on the wrist  27  of a wearer. The invention comprises body  16 , battery casings  22  and  24 , discharge electrodes  14  and  15  and LED  26 . The LED shows when the device is “on” and “off” and remains illuminated when the device is fully charged with a discharge voltage. This drawing shows the relationship between the various components of invention  10  and a person skilled in the art of design would understand that the invention is intended to adapt a comfortable profile so that it can be worn for long periods and easily deployed against an attacker. Other profiles are possible. The size of the invention is shown to a generally accurate scale with respect to the wrist  27  of the wearer. It can be configured to be smaller than illustrated depending on the type of battery used and circuit design. The device is secured to the wrist  27  of the wearer by adjustable strap  29  which is looped around the battery casings  22  and  24  by loops  23  and  25 . The strap is adjusted by a VELCRO™ type loop and hook fastener or some other suitable means. As previously mentioned, the battery casings  22  and  24  do not necessarily have to be connected to the body  16  as shown but can be independent of the body  16  for attachment elsewhere on the user in a battery magazine, for example, a battery magazine worn on a waist belt. 
         [0019]    Referring to  FIG. 3 , there is shown a top view schematic drawing of one example of the invention  10  comprising a body  16  containing the circuitry shown in  FIG. 1  and the battery casings  22  and  24 , the LED  26 , the discharge electrodes  14  and  15 , the on/off switch  20  and the discharge button  21 . Loops  23  and  25  are shown in cross section around the battery casings  22  and  24  and through slots  31  and  33  between the battery casings and the body  16  of the device. The discharge button permits discharge of the capacitor so that the invention can be stored safely in a discharged state. 
         [0020]    Referring to  FIG. 4 , there is shown a schematic drawing of a rear view  20  of one example of the invention  10  with the strap omitted. The invention comprises body  16 , an on/off switch  20 , a discharge button  21  disposed above the on/off switch and the batteries  22  and  24 . 
         [0021]    Referring to  FIG. 5 , there is shown a side view of on example of the invention  10  without the strap and comprising body  16 , an on/off switch  20 , a discharge button  21 , battery casing  24 , discharge electrode  14  and LED  26 . The angle  40  of the front face  42  is illustrated as being 60 degrees. This is one optimum angle of attack for the electrodes to ensure that they contact the skin of the attacker simultaneously so the capacitor is able to discharge. Other embodiments of the invention with other profiles of body  16  may have different optimum attack angles. 
         [0022]    Referring to  FIG. 6 , there is shown an electrical schematic drawing of another example of the invention. The voltage source  50  is a pair of 1.5V AAA size batteries although other battery sizes and voltages can be used with the invention. Resistor R 1   52  is about 7.5 k ohms. First switch  54  is the on/off switch for the device and LED  56  glows red when the device is on. When the device is fully charged LED  58  glows green. Second switch  60  is a hand-held switch like a “dead man&#39;s switch” which must be closed in order to discharge the device. The switch would be in the hand of the wearer like a spring trigger. When depressed the device is capable of discharging but when no depressed the device is not able to discharge or ceases discharge. This prevents the contacts from sticking to a skin surface. The second switch  60  is connected to the circuit by way of a wire attached across the leads of the switch that connects to the hand-held trigger. Resistor R 2   64  is 100 ohms and resistor R 3   66  and R 4   68  are both 20 k ohms. Capacitor  70  is 224J 400VDC. The circuit also includes transistor  72  and step-up transformer  74  the high voltage side of which is connected to capacitor  70 . 
         [0023]    Referring to  FIG. 7 , there is shown one example of the invention  78  similar to that shown in  FIG. 3 , with the hand switch  80  comprising a body  82  a thumb button  84  and a spring  86  connected to the body  16  of the device by wire  88 . The body is grasped by the hand and the device cannot be discharged until the wearer depresses thumb button  84 . 
         [0024]    Although the description above contains much specificity, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. Thus the scope of the invention should be determined by the appended claims and their legal equivalents.