A bottle crushing machine having a feed chamber, at the bottom of which is located a crusher disk. The disk includes a set of beater bars extending upward into the feed chamber to intercept falling bottles and initially shatter them. Near the surface of the disk are cross bars that further crush the glass fragments. The disk is situated in a portion of the feed chamber under the upper surface of an expanded portion of the chamber. The only route for glass fragments to exit the chamber is between the disk and the upper surface of the expanded portion, between the side walls of the expanded portion and the outer edge of the disk, to an area below the disk. By relative movement of the disk in the vertical direction, the gap between the disk and the upper surface will be varied, adjusting the size of fragments that are created.

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