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Allara (Al-E) did clamps with a hinge arrangement like this. Their design is a bit different as I recall it.

Here is one pattern from them -



It is possible yours may be Allara and just from a different pattern/era than the type in this image.

Edit:

Here is a larger format image which shows this design a bit more clearly -



The black piece is a roller which permits the user to roll their bottle in and out of the cage.

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