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Renin Angiotensin Mechanism.

Rotary Tablet Press: Multiple Station Tablet Machine.

Rotary Tablet Press.



  • It is also called multi-station tablet press.

  • Multi-station presses are termed rotary because the head of the machine that holds the upper punches, dies and lower punches in place rotate.

  • As the head rotates the tablet granulation runs from the hopper through the feed frame into dies.

  • Feed frame promotes a uniform fill of the die.

  • Compression takes place as the upper and lower punches pass between a pair of rollers.

  • The up and down movement of the punches is guided by fixed cam tracks.

  • The portion of the head that hold the upper and lower punches are called upper and lower turrets and the portion holding the dies are called the die table.

  • Rotary Tablet Press

  • At the start of a compression cycle, granules from hopper empty into the feed frame, which has several interconnected compartments.

  • These compartments spread the granules over a large area to provide time for the dies.

  • Weight Adjustment cam guides the lower punches to the bottom of their vertical travel, allowing the die to the cam, which reduces the fill in the dies to the desired amount.

  • A wipe-off blade at the end of the feed frame removes the excess granulation and backs it into the front of the feed frame.

  • Next, the lower punch travel over the lower compression roll and upper punches ride below the upper compression roll.

  • The upper punch enters a fixed distance into the dies, while the lower punches are raised and compact the granules within the dies.

  • To regulate the upward movement of the lower punches, the height of the pressure roll is changed.

  • After compression, the upper punches are withdrawn by upper punch raising cam and lower punch ride up by the cam, which brings the tablet above the surface of the dies.

  • The tablet strikes a sweep off blade attached at the front of the feed frame and slides down to the receiver.

  • At the same time, the lower punch reenters the pull-down cam and the cycle is repeated.

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