WO2008120022A1

WO2008120022A1 - A carabiner

Info

Publication number: WO2008120022A1
Application number: PCT/GB2008/050235
Authority: WO
Inventors: Simon Neve; Brian Obsourne
Original assignee: Balfour Beatty PLC
Current assignee: Balfour Beatty PLC
Priority date: 2007-04-02
Filing date: 2008-04-01
Publication date: 2008-10-09
Anticipated expiration: 2009-10-02
Also published as: GB2448137A; GB0706414D0

Abstract

A carabiner (1) comprises a sensor arrangement (9) for detecting the presence of an object within the carabiner enclosure (8), and an indicator device (14) for indicating that there is no detected object.

Description

A CARABINER

The present invention relates to carabiners.

Typically, a carabiner is a device made up of a metal loop with a sprung or screwed gate. Figure 1 shows a carabiner of known type, comprising a body 2, gate 3, hinge 4, spring 5, pin 6 and notch 7. Generally, the body 2 of a carabiner has a C-shape. Attached at one end of the body is a gate 3 pivoted about an axis 4. The second end of the body is equipped with a notch 7. The gate 3 is urged by the spring 5 to pivot to a closed position forming an enclosure 8. The free end of the gate 3 is equipped with a pin 6 which is received by the notch 7.

Typically, an object is connected to a carabiner by pushing the object through the gate 3 into the carabiner enclosure 8. Opening the gate 3 and passing the object back through the open gate releases the object. This operation cannot take place by accident because the gate is spring-biased into a closed position, so that the removal of an object from the carabiner is a more complicated manual operation.

The body of a carabiner can take any shape, but they are typically oval, pear- shaped or D-shaped. The gate can be locking or non-locking, depending on the level of security desired. A locking gate typically has a threaded sleeve which is screwed over the end of the body to prevent accidental opening of the gate.

Carabiners are generally used to join two objects together such as climbing harnesses to safety lines. In one mode of operation, both objects are passed through the carabiner gate 3 into the carabiner enclosure 8. Alternatively, carabiners can be made so that they are permanently attached to an object, such as a harness. This can be done by sewing a lanyard or rope to the body of the carabiner. Alternatively, the body of the carabiner can be equipped with a slot or hole where a lanyard of rope can be attached. Carabiners are devices used to quickly and reversibly connect components together. As such, carabiners are often used to link a user wearing a safety harness to a safety line, where the user is engaged in a potentially dangerous activity and where the user also requires a certain degree of mobility. The user is often in an elevated or precarious position. Carabiners allow users to move relatively free along safety lines, and allow these users to clip on and off the safety lines with relative ease. However, if the user slips or falls, the carabiner serves to attach the user to the safety line, thus greatly reducing the risk of serious injury or death to the user.

The ease with which carabiners can be attached to rings, loops or fixed ropes has led to the wide use of carabiners in many potentially dangerous recreational activities such as climbing, caving or sailing, as well as non- recreational activities such as emergency rescue, construction, window cleaning and the inspection and maintenance of outdoor structures.

The safe use of a carabiner relies on the user being vigilant in attaching the carabiner to a safety line and/or to the harness. The user may become distracted or disoriented in a busy working environment, or may simply forget to attach the carabiner to the safety line. The failure to attach a carabiner to a safety line can, if the user slips or falls, result in the serious injury or death of the user.

However, monitoring and enforcing the correct use of a carabiner is difficult.

According to a first aspect of the invention, there is provided a carabiner arrangement comprising a surround and a gate for providing access to an enclosure defined by the surround and the gate, wherein the carabiner arrangement further comprises a sensor arrangement for detecting the presence of an object within the carabiner enclosure, and an indicator device for indicating that there is no detected object, wherein the sensor arrangement detects continuity of an electric circuit, and wherein continuity is provided by the object within the carabiner enclosure. The carabiner of the present invention provides a mechanism for alerting the user and/or work colleagues that the user is not safely attached by the carabiner to a safety line or other structure. The user is thus reminded to attach to the safety line, either directly or by work colleagues.

By detecting continuity of an electric circuit made by the object to be detected, there is no need for any moving parts, and a simple and reliable detection mechanism is formed.

There are a number of different ways to implement the sensor arrangement.

One implementation uses an electrical circuit through the carabiner surround, wherein an object in the carabiner enclosure completes the electrical circuit to ground. Another implementation uses a pair of conductors, wherein an object in the carabiner enclosure shorts the pair of conductors together. These approaches use a simple electrical circuit to detect continuity. This is suitable for applications in which the object to be retained in the carabiner is a conductor. This is the case in most applications, as the safety line will often be a metal cable.

According to a second aspect of the invention, there is provided a carabiner arrangement comprising a surround and a gate for providing access to an enclosure defined by the surround and the gate, wherein the carabiner arrangement further comprises a sensor arrangement for detecting the presence of an object within the carabiner enclosure, and an indicator device for indicating that there is no detected object, wherein the sensor arrangement comprises a radiation source and radiation detector, for detecting the presence of an object in the enclosure.

This can be a line of sight type arrangement. A carabiner typically has a shape which hangs always the same way from a cable. For example, a pear shape is common, and this will normally hang from the sharper bend. As a result, it is known where the cable will be situated within the enclosure, and the line of sight arrangement can detect presence of the cable in the known position.

This arrangement again avoids the need for any moving parts.

The sensor arrangement can be adapted to detect a number of objects within the carabiner enclosure. This may be useful if the user is required to retain two items in the carabiner, for example a cable associated with a harness of the user and a safety line.

A signal used to indicate that there is no detected object can be audible and/or visual and/or can be a vibration.

A further modification can use a memory for storing data from the sensor arrangement. This can be used for training purposes. A GPS system can also be used so that it is known at what times the user should have been coupled to a safety line based on their position.

Examples of the present invention will now be described with reference to the accompanying drawings, in which:

Figure 1 shows a carabiner of known type;

Figure 2 shows a first embodiment of a carabiner of the present invention;

Figure 3 shows a second embodiment of a carabiner of the present invention;

Figure 4 shows the carabiner of Figure 3 in use; and

Figure 5 shows a third embodiment of the carabiner of the present invention.

The invention provides a carabiner which has a mechanism for alerting the user and/or work colleagues that the user is not safely attached by the carabiner to a safety line or other structure. Figure 2 shows a first embodiment of the invention, which comprises those features of the general type as shown in Fig 1. The carabiner further comprises a sensor arrangement 9 in the form of a pair of closely spaced wires. These are insulated from the material of the carabiner. Each wire connects to an indicator device 14, and the wires are disconnected from each other. A cable within the enclosure provides a short circuit between the wires, and this completes an electric circuit. This is detected by the indicator device, and it produces an output in the form of a buzzer (shown as 15) and/or light when the circuit is not connected.

In this example, when the circuit is made, the buzzer/light is turned off, and this inversing function can be implemented by a simple transistor or other logic circuit.

The indicator device is electrically connected to the carabiner by wires passing in the lanyard, and the indicator device can be carried in the clothing of the user.

In an alternative but similar arrangement, the cable in the enclosure can provide an electrical path to ground. The indicator device then detects a continuous circuit through the carabiner enclosure, and the retained cable to ground, and provides the same warning as above.

Figure 3 shows a second embodiment of the invention which comprises a sensor arrangement 9 in the form of a plurality of pressure detectors 10. Each pressure detector 10 is a spring-loaded electrically conductive bearing (spring not shown) having an insulated region 11. The pressure detectors 10 are biased to project into the carabiner enclosure 8 so that the non-insulated portion of the pressure detectors 10 completes the electrical circuit 12. A power supply 13, preferably a battery, powers the indicator device 14.

In this case, the indicator device can simply power the output device, as the sensor arrangement already provides a positive output when the enclosure is empty (unlike the examples above). Figure 4 shows the arrangement of Figure 3 when an object 16 has been inserted into the carabiner enclosure 8. In use, the object 16 moves the pressure detectors 10 from a first position 17, to a second position 18. The insulated region 11 breaks the electrical circuit 12 and the buzzer 14 turns off. The carabiner thus has a sensor arrangement for detecting the presence of an object 16 within the carabiner enclosure 8, and an indicator device 14 for indicating that there is no detected object.

Figure 5 shows a further embodiment in which the sensor arrangement comprises a line of sight sensor, in the form of one or more emitters 19, which emit radiation detectable by detectors 20. These may be IR or laser devices, for example. The emitters 19 are arranged so that they are substantially directed towards the detectors 20. The detected profile is varied when an object is present, as a result of the interruption of one or more paths. This type of arrangement can detect an object in a single location, or it may be arranged to detect the presence of an object at any location within the enclosure.

In its simplest form, a single emitter and a single detector can be provided, as a simple line of sight detector. The use of multiple emitters and detectors enables multiple discrete locations to be detected, or even the full volume of the enclosure. This may require signal processing capability to interpret the detector signals received.

Figure 5 shows the indicator device 21 in the form of a light output (such as an LED). The electrical circuitry connecting to the emitters and detectors has not been shown.

The carabiner of Figure 5 is connected to a lanyard 24, which is threaded through a slot 23 to form a loop. The loop of lanyard 24 is permanently fixed around slot 23 by stitching 25. The lanyard also houses part of the internal electrical circuitry required to connect the emitters 19 and the detectors 20 to the indicator device 21 and to the power supply 13. The emitters and detectors in Figure 5 are located so that they use light paths across the enclosure. Instead, a light path can be defined around the inner surface of the carabiner enclosure, for example by designing the surface to have a provide a path of light using total internal reflection. If an object is present against the surface, this can interrupt the total internal reflection, and cause a break in the signal path.

A further alternative arrangement is to provide a circuit which includes a switch, the switch being operated when an object passes through the gate. This can be a spring loaded tracer wire near the gate mechanism.

A further alternative arrangement is to provide a circuit which drives a current around the carabiner, causing a magnetic flux, and a change in detected magnetic flux intensity is used to detect the presence of a metal (ferrous) object.

The system can include a GPS system so that the location of a user is known. This enables the times when the safety line should have been used to be determined. Together with information stored from the sensor arrangement, this can enable evidence to be obtained to show whether or not the required safety guidelines have been followed. This can be used for training purposes, or for disciplinary purposes, as a further way to ensure that safety procedures are followed.

The device of the invention requires the user to deliberately ignore the warning signals in order to continue working in an unsafe environment. This greatly increases the likelihood that the expected safety measures will be adopted.

The circuits required to implement the desired function of detecting the absence of an object in the carabiner will be routine to those skilled in the art. It will be clear from the description above that there are numerous ways to implement the sensor arrangement, and only a few have been shown in any detail. These fall into various categories; optical sensing using interruption of an optical path, electrical sensing using interruption of an electrical circuit by a cable in the enclosure, electrical sensing using making of an electrical circuit by a cable in the enclosure.

Other techniques are possible, such as pressure sensing, and gate operation detection. Furthermore, magnetic or electric field detectors can be used, and detect when an electric or magnetic field is interrupted by the presence of an object in the enclosure.

Other versions and modifications will be apparent to those skilled in the art.

Claims

1. A carabiner arrangement comprising a surround and a gate for providing access to an enclosure defined by the surround and the gate, wherein the carabiner arrangement further comprises a sensor arrangement for detecting the presence of an object within the carabiner enclosure, and an indicator device for indicating that there is no detected object, wherein the sensor arrangement detects continuity of an electric circuit, and wherein continuity is provided by the object within the carabiner enclosure.

2. A carabiner arrangement as claimed in claim 1 , wherein the sensor arrangement comprises an electrical circuit through the carabiner surround, wherein an object in the carabiner enclosure completes the electrical circuit to ground.

3. A carabiner arrangement as claimed in claim 1 , wherein the sensor arrangement comprises a pair of conductors around the surround, wherein an object in the carabiner enclosure shorts the pair of conductors together.

4. A carabiner arrangement comprising a surround and a gate for providing access to an enclosure defined by the surround and the gate, wherein the carabiner arrangement further comprises a sensor arrangement for detecting the presence of an object within the carabiner enclosure, and an indicator device for indicating that there is no detected object, wherein the sensor arrangement comprises a radiation source and radiation detector, for detecting the presence of an object in the enclosure.

5. A carabiner arrangement as claimed in any preceding claim, wherein the sensor arrangement is adapted to detect a number of objects within the carabiner enclosure.

6. A carabiner arrangement as claimed in any preceding claim, wherein the detectable signal is audible and/or visual and/or is a vibration.

7. A carabiner arrangement as claimed in any preceding claim, further comprising a memory for storing sensor arrangement data.

8. A carabiner arrangement as claimed in any preceding claim, further comprising a location tracking device.

9. A carabiner arrangement as claimed in claim 8, wherein the location tracking device is for recording GPS data.

10. A safety harness comprising a carabiner according to any of the proceeding claims.