Patent ID: 8764430

Claim:
A press device for manufacturing tablets from a mixture of at least one component, comprising: a turntable ( 1 ) in which is arranged at least one die ( 2 ) for receiving the mixture, at least one compaction assembly comprising a first punch ( 3 ) and a second punch ( 4 ), said first and second punches being laid out on either side of the turntable ( 1 ) facing the die ( 2 ), and being mounted so as to be translationally mobile coaxially with the die ( 2 ), first control means ( 7 ) and second control means ( 8 ) for controlling axial displacement of the first punch ( 3 ) and of the second punch ( 4 ) respectively, said first ( 7 ) and second ( 8 ) control means comprising means co-operating for maintaining the first ( 3 ) and second ( 4 ) punches in a fixed axial position in which the first ( 3 ) and second ( 4 ) punches define a confinement volume (V) with the die ( 2 ), wherein the first control means ( 7 ) comprise a compaction cam ( 9 ) for displacing the first punch ( 3 ) into a compaction position, said compaction cam ( 9 ) comprising a cam path on which said first punch ( 3 ) is capable of being displaced, the cam path comprising a planar portion ( 90 ) substantially perpendicular to the axis of the first punch ( 3 ), the planar portion ( 90 ) extending over an angular section comprised between 5° and 170° for maintaining the first punch ( 3 ) in the die ( 2 ) at a fixed compaction axial position during a determined compaction-maintaining time, the second control means ( 8 ) also comprising means for maintaining the second punch in said die at a fixed compaction axial position at least during said compaction-maintaining time, so as to maintain, during said compaction-maintaining time, the confinement volume (V) at a constant volume corresponding to a compaction volume for forming the tablet, and wherein the compaction cam ( 9 ) comprises three stress sensors (C 1 ;C 2 ;C 3 ) distributed in three cavities made in the compaction cam ( 9 ) for measuring stresses undergone by the cam path upon passing of the first punch ( 3 ), said three cavities being formed at a center and at two ends of the planar portion ( 90 ) of the cam path, respectively.