Chicken hutch door catch

The idea of this catch is to enable a sliding chicken hutch (or similar) door to be lifted by a string but to prevent it being pushed up by a fox or other animal.

The string runs through the locking catch and bracket. When pulled, it lifts the catch clear of the lock position.
When the door is pushed up the catch engages as a lock

In my example, it locks onto the wire bar of the weldmesh behind it
It would also work on a smooth surface if you provide an edge to engage the lock.

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