Page 26 - Kim Hong Tee - Design Booklet Year 3

Current Trigger Mechanism

Trigger Mechanism Study

This a study of the Ferrex glue gun mechanism on how the trigger is pulled to feed in the glue sticks in. The objective here is to reduced the trigger
reach at the mechanism level, to reengineer the mechanism to minimise the trigger reach at the dormant state.

The following image shows the stages of the glue gun in the dormant stage to a fully pulled stage, using line graphs and dots to simplify the study of

the mechanism, the black dots are the fixed point, the black lines are the hands, the orange dots are the moving joint point, the light blue is the spring,
the red dot and the dotted line is a moving point along a track, and the grey hook is the hook that feeds the glue sticks into it.

At the first/dormant stage, the hook is not deploy and stays under the feeder tube. After that at the second stage, with the trigger pulled a little bit, the
hook is activated grabing the glue stick and ready to hook it into the melting barrel. Lastly, at the third stage where the trigger is fully pulled, the hook

bites onto the glue stick and push it into the melting barrel, and the action repeats.

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