Precision punch running inertia force

2022-06-17

When the precision punch is running, the inertial force generated by the crank connecting rod slider mechanism is much larger than that of the ordinary punching machine. This inertial force causes the high-speed punching machine to produce vibration and noise pollution and reduces its stamping accuracy. It is extremely important to balance the inertial forces.
The inertial force of the high-speed punch is the vibration generated by the punch through the vertical force, the horizontal force and the force acting on the guide rail surface of the slider. Usually, the amplitude of the inertial force exceeds 20 times the weight of the slider, so the vertical inertial force is larger than the total weight of the punching machine. Such a huge inertial force can have a very serious impact on the normal stamping production of the punching machine, and the corresponding inertial force must be taken. balancing measures.
In order to reduce the inertial force and improve the balance effect of the inertial force, the quality of the rotating part and the reciprocating motion should be minimized. Since the high-speed reciprocating motion of the high-speed punch of the slider is the main source of the inertial force, while ensuring the strength, the slider should be moved. The quality of the machine is designed to be as small as possible (such as middle drilling, using high-strength and low-density alloys such as light alloy cast aluminum sliders, etc.); using double crankshaft two-point or four-point transmission mode; using advanced, high adjustability, maintenance Simple dynamic balancing device.
Due to the large inertia force of the high-speed punch, the size of the pneumatic balance cylinder is too large, the speed of the slider is too high, and the pneumatic sealing ring cannot bear it. The upper and lower chambers of the pneumatic balance cylinder need frequent intake and exhaust, and there is no suitable pneumatic valve to meet this requirement Too fast commutation frequency, therefore, it is not suitable to use the inertial force balance method in the form of a pneumatic balance cylinder on a high-speed punch.

The inertial force of the crank-slider mechanism includes three parts: the centrifugal inertial force generated by the rotating motion of the crankshaft; the reciprocating inertial force generated by the reciprocating motion of the slider; the inertial force generated by the plane motion of the connecting rod. Among them, the inertial force generated by the plane motion of the connecting rod is the most complicated. The C-type punch project uses the two-mass substitution method to equivalently convert the connecting rod mass to the hinge point of the connecting rod and the crank pin according to the static equivalent conditions, and then combines it with the crankshaft to calculate the rotational inertia force.

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