A hammer assembly (51) for a glass bottle breaking apparatus comprises a shaft (52), a series of collars (53) secured on the shaft (52) and spaced one from another longitudinally of the shaft (52), a series of links (58) each being pivotally connected to a corresponding one of the collars (53) and a series of hammers (55) each being connected for pivotal movement relative to a corresponding one of the links (58), the arrangement being such that the links (58) are each provided with a curved profile (65) for locating an adjacent portion of the shaft (52) so that if, in operation, one of the hammers (55) should strike a glass fragment obstruction without dislodging it immediately, the link (58) associated with the hammer (55) will wind up on the shaft (52) thus reducing a radial displacement between the link (58) and the shaft (52) and drawing the hammer (55) under the obstruction without causing jamming of the apparatus.