Stamper-holding apparatus for use in injection mold

Claim 1

In a stamper holding apparatus for use in and injection mold comprising a stationary mirror block having a first mirror surface, a movable mirror block having a second mirror surface, said movable mirror block being reciprocable relative to said stationary mirror block, an annular stamper disposed on one of said first and second mirror surfaces, and a holding structure for supporting the outer circumferential edge portion of said stamper so as to hold said stamper between said one mirror surface and said holding structure, the improvement which comprises: a plurality of first side actuation units arranged around the outer periphery of said stationary mirror block and spaced radially outwardly from said stamper, a plurality of second side actuation units arranged around the outer periphery of said movable mirror block and spaced radially outwardly from said stamper, said first side actuation units having first operating rods and said second side actuation units having second operating rods, said first and second operating rods being operable in opposing directions relative to said stamper, said holding structure being located between said first and second actuation units and comprising a member movable back and forth in a direction transverse to the direction of movement of said operating rods between two positions, said member being alternately engageable with and disengageable from said first and second operating rods at said two positions so that when said member is in one position with said first operating rods engaging said member, said second operating rods are disengaged from said member, and when said member is at the other position with said second operating rods engaging said member, said first operating rods are disengaged from said member.