Gooseneck (bracket)

Reading lamp with gooseneck

A gooseneck or flex arm is a semi-rigid, flexible connecting element made from coiled metal tubing . Similar to its natural role model, it can be bent in almost any direction and remain in any position. Areas of application are movable brackets for lights, magnifying glasses, microphones , etc. The hollow shape of the gooseneck allows electrical cables or fiber optic cables to be accommodated inside, for example.

construction

Detail of the gooseneck bracket for a reading lamp

A gooseneck contains a wire with a round cross-section inside, which has been shaped like a spring in the shape of a helix. A wire with a triangular cross-section is wound around this, so that the tips of the triangle protrude between the round wires into the inner spiral. If the gooseneck is bent in one direction, the distance between the round wires is slightly larger on the outside and slightly smaller on the inside. Correspondingly, the tips of the triangles slip outside between the round wires or are pushed out inside. The bend in the gooseneck is retained due to the friction between the inner spiral and the outer casing, so that the gooseneck remains in the set position.

Schematic representation and cut

straight

bent

Outer wire pushed between round wire (outer curve)

Outer wire pushed out of the gaps

Construction of a gooseneck from round wire helix with triangular wire wound over it (longitudinal section)

Applications

Goosenecks are used as brackets when quick, freely positionable alignment is required.

As components of lamps, the connecting elements are also called light holder tubes . Their high flexibility is used to adjust the lighting individually to the needs. The power supply for the lamp is provided through the inside of the gooseneck. The same applies to illuminated magnifiers, where the magnifying glass is held in addition to the lamp.

Applications in fiber optics are also typical. As microscope illumination, fiber optic bundles inside the gooseneck guide the light from a cold light source specifically to the area to be examined. The rigid shape of the gooseneck eliminates the need for additional stands or brackets.

Gooseneck constructions are used in automobiles to hold navigation systems or mobile phones. In the 1970s, the manufacturer Blaupunkt manufactured a number of car radios with a control unit on the gooseneck; so the models Berlin , Sylt and BEQ-S (equalizer) .

In some cases, the flexible arms are also used to carry out work in inaccessible places. Magnets or grippers at the end of the gooseneck can be used to 'fish out' of small parts from inaccessible places, a mirror or lighting allows glimpses into hidden corners. A gooseneck on a stick lighter enables easy lighting in hard-to-reach positions.

When used as a coolant hose on machine tools , a hose is pulled inside the gooseneck. A jet of liquid can be dosed with pinpoint accuracy. Today, however, liquid or air for cooling and rinsing is mostly passed through a chain of plastic fittings (articulated hose) plugged together like a ball joint, which retain their curvature with a suitable holding force.