Feather center
The spring center punch or self-releasing center punch is a tool used in metalworking that can be used to provide metal or plastic parts with a small indentation, the so-called grain size. In contrast to the normal center punch , which is used with a hammer, the spring center punch works with spring force . Usually, the grain is used to give a drill the first guidance (centering), in the technical assistance z. B. by the fire brigade leads to the controlled destruction of toughened safety glass .
Use in technical assistance
Like the emergency hammer in buses and trains, the spring center punch is used by rescue workers for the controlled destruction of toughened safety glass (e.g. side and rear windows in cars ) and is therefore a tool for technical assistance . In terms of appearance, the pen center resembles a pencil . There is a steel tip at the tapering end , and a spring is located inside the device . Feather grains can develop a compressive force of up to 16 kg. On some models, it can be continuously adjusted by turning the rear end.
functionality
The pane to be destroyed is often masked with adhesive tape or special adhesive films beforehand. This protects patients and emergency services from splinters flying around in an uncontrolled manner and the disc can still be removed in one piece after punching. People in the vehicle are additionally protected from any glass splinters by means of a soft patient protection (e.g. a transparent film). Then the spring center punch is placed in the edge area of the glass and light pressure is applied to the device. If possible, the pane should be secured from falling from the inside if there is still an injured person in the work area. As a result of the pressure exerted on the grain, the steel point snaps against the glass and lets it burst. The pane can now be pushed out in one piece and removed from the danger area.
In addition to the conventional self-releasing center punch, there are also so-called safety spring centers especially for use in technical assistance. These work with an external spring balancer and are tensioned by manually pulling out the spring. When you let go, a bolt hits the tip and destroys the glass. The advantage: In contrast to the standard grain, no pressure has to be exerted on the disc, so there is no risk of punching your hand through the grained disc and causing cuts.