Classification and die of tablet press machine

Classification and die of tablet press machine

The tablet press can be divided into single punch tablet press and multi punch rotary tablet press.

The single stamping machine is to press the tablet through the cam (or eccentric wheel) linkage mechanism (similar to the working principle of the punch) to make the upper and lower punch produce relative movement to press the tablet. The single punch type does not necessarily have only one die working, but can also have two or more pairs. However, multiple pairs of dies can punch at the same time, which results in strict requirements for the stability and reliability of the mechanism, and the structure is complex, so it is rarely used. Single punch tablet machine is intermittent production, intermittent feeding, intermittent tablet, low production efficiency, suitable for laboratory and large-scale tablet production.

The multi punch rotary tablet press is a circular device of multiple punching dies on the working turntable. The tail of each upper and lower punching is controlled by a fixed lifting guide rail. When the upper and lower punch rotate synchronously with the rotary table, they are controlled by the guide rail to do the axial lifting movement, thus completing the tablet pressing process. At this time, the process of the tablet press is continuous, continuous feeding and continuous tablet. From the whole machine point of view, the force is more uniform and stable, which is widely used in the formal production. Multi punch rotary tablet press is usually designed according to the punch module, such as 19 punch, 35 punch, etc.

Die

The die is a tablet press mold for pressing tablets. The upper and lower working end faces form the surface shape of the tablet, and the diameter of the middle die is the diameter of the tablet.

Stamping die is the main working component of tablet press. Generally, a pair of stamping die includes three parts: upper punch, middle punch and lower punch. The structure of upper and lower punch is similar, and the diameter of punch is the same. The punch diameter of upper and lower punch is matched with the die hole of middle die, which can slide up and down freely in the middle die hole, but there is no gap that can leak powder.

According to the structure shape of the die, it can be divided into circle and special shape (including polygon and curved line). The shape of punch end face includes plane shape, bevel shape, shallow concave shape, deep concave shape and comprehensive shape, etc. plane shape and oblique side shape punch are used to press flat cylinder shaped tablet, shallow concave shape is used for pressing double convex surface tablet, deep concave shape is mainly used for pressing chip of coated tablet, and comprehensive shape is mainly used for pressing special-shaped tablet. In order to identify and take medicine conveniently, drug name, dosage and vertical and horizontal lines can also be engraved on the end face of the die. In order to press different doses of tablets, a suitable die should be selected.