GB2242399A - Adjustable strap for an electronic tagging device - Google Patents

Abstract

An adjustable strap 10 for attaching an electronic tagging device 110 a wearer's wrist or ankle is described in which opposed ends 6, 6 of the strap are permanently connected to the device, the strap constituting a VHF aerial and D.C. link for the tagging device. The strap is placed over the wrist or ankle so that it loosely encircles same, it being rigidly attached thereto by pinching together any excess length of the strap, folding back the pinched together region 12 to lie adjacent the strap and sliding a sleeve 11 over the pinched together region and the adjacent strap, and securing the sleeve to the strap. <IMAGE>

Description

ADJUSTABLE STRAP This invention relates to an adjustable strap and is particularly applicable to an adjustable strap for use with electronic tagging devices.

An electronic tag is normally worn by a "client", usually on the wrist or leg, and may be used to determine whether the wearer of the tag has remained in a defined area, usually in the home, during defined curfew hours. The strap of the tag is an important feature which, apart from securing the tag to the wearer, usually contains the VHF aerial and also plays a key role in ensuring that the tag is tamper resistant.

The strap must be easily, quickly and safely fitted to the client "in the field", perhaps in th clients home or in a court room. Known methods of strapping an electronic tag to a client have involved the strap being externally connectable to the tag or have involved the strap being cut to length and have suffered from the difficulty in guaranteeing that the strap affords a robust, reliable, waterproof and tamper resistant electrical connection to the tag.

It is an object of the present invention to provide an improved form of adjustable strap particularly suited for use with electronic tags.

According to the present invention there is provided an adjustable strap for attaching an associated device to a supporting member, said strap having opposed ends permanently connected to said device such that with said device it may be placed over said member to loosely encircle same, said device being adapted to be rigidly attached to said supporting member by pinching together any excess length of said strap, folding back the pinched together region to lie adjacent said strap, and by providing a sleeve which is positioned over the pinched together region and the strap adjacent thereto and which is secured to said strap.

It may be arranged that the sleeve is permanently positioned on said strap and is slid over said pinched together region.

In a preferred arrangement according to the invention there is provided a strap as aforesaid in combination with an associated electronic tagging device, said strap being adapted to attach said tagging device to a human limb.

In carrying-out said preferred arrangement it may be arranged that said tagging device includes a transmitter and that said strap incorporates an antenna for said transmitter, and, preferably, a D.C.

link for said transmitter.

An exemplary embodiment of the invention will now be described reference being made to the accompanying drawings, in which: Figure 1 is a partially block schematic diagram of an electronic tagging device to which the adjustable strap of the present invention is particularly applicable; Figure 2 depicts an adjustable strap in accordance with the present invention connected to the electronic tagging device of Figure 1; and, Figure 3 to 7 depict successive stages used in attaching the strap and tagging device of Figure 2 to a human limb.

In Figure 1 there is shown an electronic tagging device 1 which is designed to be worn by a "client" either on the wrist or leg and is used to determine whether the wearer of the tag has remained in a defined area, usually the home, during defined curfew hours. The electronic tagging device 1 of Figure 1 comprises a VHF transmitter 2 which is powered from a battery 3 which is indirectly connected between supply terminals VCC and E (earth) of the transmitter 2.

The transmitter 2 is also provided with an "RF OUT" terminal 4 which is connected to via a blocking capacitor 5 and an antenna terminal 6 to a loop antenna 7, the other end of which is connected via an earth terminal 8 to the supply terminal E of the transmitter 2. An inductor 9 is also provided, connected between the battery 3 and the antenna terminal 6, whereby the antenna 7 constitutes a DC link in the power supply circuit to the transmitter 2.

The electronic tagging device of Figure 1 normally operates by transmitting, typically, an 8-bit signal pulse at very short intervals to a receiver. The receiver can be attached to a nearby telephone which can be intermittently interrogated, during curfew hours, by a main computer at a surveillance centre. The signal transmitted by the tagging device uniquely identifies it to the surveillance centre and may also be used to indicate when a low battery power state exists.

The system sensitivity is tuned in accordance with the particular surrounding which the electronic tagging device is used in and any received signal level below a specified limit indicates a curfew violation.

In Figure 2 of the drawings there is depicted the electronic tagging device 1 of Figure 1 connected to an adjustable strap 10 by means of which it may be rigidly attached to a "client". Each end of the strap 10 is permanently "factory fitted" and sealed to the body of the device 1 and is provided with an integral metal band or wire (not shown) which constitutes the loop antenna 7 of the tagging device 1.

The loop antenna 7 is permanently connected to the terminals 6 and 8 of the tagging device 1, and also constitutes the D.C. link to the device 1 as has already been explained.

The adjustable strap 10 of Figure 2 is made sufficiently long so that it can be slid over a hand or foot and it is provided with an adjustable sleeve 11 the purpose of which will be described later.

In order to rigidly attach the electronic tagging device 1 or Figure 1 to a "clients" wrist, the strap 10, with the device 1, is slipped over the hand and onto the wrist. Any excess length of the strap 10 is then pinched together as shown at 12 in Figure 3 of the drawings.

The pinched together region 12 may then, optionally, be secured together, such as by a rivet or eyelet 13, pre-made holes (not shown) possibly being provided in the strap 10 for this purpose.

The pinched together region 12 is then folded-back to lie closely adjacent the strap 10 as shown in Figure 5 and sleeve 11 is slid over the folded back region 12 and the adjacent part of the strap 10, as is shown in Figure 6, and the end view of Figure 7, and the sleeve 11 is secured to the strap 10 in some suitable way.

In this way the adjustable strap 10 enables the electronic tagging device 1 to be easily attached to a "client" in the home, court room, or wherever and provides a substantially tamper-proof attachment. The device may only be removed by cutting through the strap 10 and this would have the effect of open-circuiting the loop antenna (7 - Figure 1) incorporated in the strap and breaking the D.C.

link afforded by the loop antenna, thereby open-circuiting the battery connection to the transmitter (2 - Figure 1) of the electronic tagging device 1. If this is done, the electronic tagging device 1 will stop transmitting and this will be detected by the surveillance centre when the device is next interrogated.

It will be appreciated that the adjustable strap which has been described may be made in a variety of ways and manufacturing methods dependent upon particular requirements. Thus, it is envisaged that the strap may comprise, for example, compression moulded rubber or injection moulded plastic with a thin metal steel band insert, extruded plastic coated wire, graphite foil laminated between plastic sheets, conductive rubber within a woven fabric sleeve, etc.. The sleeve sealing can be achieved quickly and simply by a variety of methods. For example, adhesive, solvent welding, low temperature heat shrink sleeving, solvent shrink sleeving. The fastening option could, for example, include a plastic ratchet rivet which presses together by hand, is almost flush fitting and is tamper resistant.

Although particularly applicable to electronic tagging devices, it will be appreciated that the adjustable strap which has been described could apply equally to similar electronic equipment requiring similar features.

Claims (7)

CLAIMS:

1. An adjustable strap for attaching an associated device to a supporting member, said strap having opposed ends permanently connected to said device such that with said device it may be placed over said member to loosely encircle same, said device being adapted to be rigidly attached to said supporting member by pinching together any excess length of said strap, folding back the pinched together region to lie adjacent said strap, and by providing a sleeve which is positioned over the pinched together region and the strap adjacent thereto and which is secured to said strap.

2. A strap as claimed in claim 1, in which the sleeve is permanently positioned on said strap and is slid over said pinched together region.

3. A strap as claimed in claim 1, or claim 2 combination with an associated electronic tagging device, said strap being adapted to attach said tagging device to a human limb.

4. A strap as claimed in claim 3, in which said tagging device includes a transmitter and in which said strap incorporates an antenna for said transmitter.

5. A strap as claimed in claim 4, in which said strap incorporates a D.C. link for said transmitter.

6. An adjustable strap substantially as hereinbefore described with reference to the accompanying drawings.

7. An adjustable strap in combination with an electronic tagging device substantially as hereinbefore described with reference to the accompanying drawings.