5.8 Stability Analysis of Machine Operation
The stability of the operation of the machine has been described above, but it is limited to a certain situation, and it is analyzed from the overall point of view. If the machine is operated stably, the load is constant and the moment of inertia should be constant. However, due to the fact that there is a mechanism for variable speed movement inside the printing press, the roller's operation has a deviating value (caused by the notch of the roller), and therefore its moment of inertia and load are all changed. The moving parts on the printing press are divided into two major categories: centered rotating and non-centering rotating. The former's moment of inertia is a constant, and the latter's moment of inertia is a variable. The total moment of inertia is:
J=J (regular)+J (variable)
To make the total moment of inertia J constant or approaching constant, J (variable) should be close to zero, which requires a minimum of non-uniform motion parts on the machine. even if:
J=J(Frequency)+J(Variable)=J(Frequency)
The total load is divided into three major categories from the major aspects: 1 the load formed by the printing pressure; 2 the load formed by the opening and closing of the tooth force; and 3 the load formed by the frictional force of each link. Due to the presence of a gap in the drum, the printing pressure changes once a week. That is non-constant load. The opening and closing force is also performed once a week. It is also a non-constant load. The friction of each link can't always be constant by the above two reasons. It can be seen from the above analysis that to make it a constant load, the printing pressure should be zero, and there is no switching action to open and close the teeth, which is obviously impossible. In the actual process, the printing pressure should be controlled to a minimum so that it is close to zero. The force to open and close the teeth should also be minimal, in addition to avoid all the junctions at the same time open and close the teeth, otherwise it will form a larger impact. It is best to allow all opening and closing teeth of the drum to work. This also includes changes in printing pressure.