Spring-loaded camming device

An active clamping device is a mobile security agent that takes climbing and mountaineering to attach a fixed point application. It has in contrast to the wedge by a spring mechanism, which allows to place the device at suitable points in the rock, such as cracks. In this case no positive engagement is necessary because the devices are designed so that the static friction of the instrument is sufficient on the rock to keep occurring in a fall of the climber force. The spring mechanism does not affect the maximum holding force. The clamping device is removed after its application from the rock and leaves no trace. Closely related to this is the idea of the clean climbing. It was not until the invention of the clamping device the commission of some routes in Clean style has become possible. Was invented in the clamping device in its present form in 1978 by Ray Jardine.

Principle of operation

The principle is based solely on the fact that over a deflecting mechanism proportional to the holding force contact force is generated. The retaining force acts on the axis of the device. About the moving segments on the axis part of the force is transmitted as a pressure force on the rock. This contact pressure ensures that the holding force can be released by friction of the rock. Clamping devices can be used in parallel cracks or even slightly opening cracks.

Application

All terminal devices have a preferred direction of loading. Only when the device is biased in this direction, it can keep the fall of a climber reliable. This direction must be taken into account when placing the device in the rock. Furthermore, it should be noted that the pressing force of the device under load can be very large ( explosive effect ). The rock must be robust enough to withstand this explosive effect. In particular, while placing behind Shed rock caution is necessary here. The surface should be free of dust and free of vegetation. To remove this device is pulled on so -called trigger that creates the segments so that they no longer touch the rock. The climber needs some experience to judge the reliability of the placed securely clamping device.

Clamping range and sizes

In order to protect different wide crack widths, all terminal devices are available in different sizes. The different sizes are numbered half of the manufacturers of simplicity. A Friend of size # 2 covers, for example, from the range of 29 up to 44 mm. A Camalot size # 2 covers 37-65 mm. The sizes of the various manufacturers have different clamping ranges. This is observed when size information is given to Friends needed in climbing guides.

Brands, manufacturers and types

• The name Friend is a product name of the company Wild Country. With the Friend in the late 1970s was brought for the first time, a clamping device on the market. The shape of the segments of Friends was not to patent protection, since it corresponds to a mathematical curve, the involute, so does not have the necessary level of invention. The inventor of the Friends, Ray Jardine, could only be the operating mechanism patented, so this is slightly different with imitation products.
• Clamping devices of the brand Camalot come from the manufacturer Black Diamond. At Camalots new generation the pivots of the clamping jaws are distributed on two axes instead of one, as with other similar clamping devices. Thus, a better clamping action and thus security can be achieved.
• Link Cams are clamping devices like the Camalots, Friends or aliens. With a base angle of 13.5 ° Link Cams ensure that the entire range can be exploited without much use of the hand. There are four jaws divided into three segments. These three segments of different sizes can be dismantled and re- wound. The span of the clamping device can thus be considerably extended in a simple manner.

Clamping devices from different manufacturers and their sizes compared

• The sizes given in brackets indicate that for the given application a further clamping device is still needed. If two variables specified without parentheses, both dimensions are necessary in approximately equal parts in order to achieve the application range of the Camalot.

Designs

The Friend has an axis, where there are four segments, two segments are aligned to the left and two to the right.

The Camalot has two axes, where there are two segments. The segments are located, which are aligned to the right and vice versa on the left axis. Through this design, a larger clamping range can be covered as the Friend. However, the second axis resulting in a higher weight.

The link has a cam shaft on which there are four segments as in Friend. The segments are in turn composed of smaller segments. Thus, the segments can be wound and unwound. This design leads to a particularly large clamping range.

The BigBro has a completely different design without axis and segments and resembles a diagonally bound tube. With BigBros cracks up to a width of 467 mm may be hedged.