Abstract
This paper examines mechanisms the operating elements of which perform linear oscillations the frequencies of which are too high for the weights of the elements. This can create a considerable nonproductive mechanical reactive inertial power, which can by far exceed the productive (useful) dissipative power. A significantly higher energy efficiency can be achieved through neutralization of the mechanical reactive inertial power. Self-neutralization of the mechanical reactive inertial power can be possible in mechanisms with a constant equivalent moment of inertia due to displaced oscillation phases of the operating elements, the number of which may, in fact, be any. For a mechanism with two operating elements, the phase displacement is /2, whereas for a mechanism with three operating elements it is 2/3. Practical use of the mechanism with a constant equivalent moment of inertia with two big operating elements may be hindered because of the lack of balance. The degree to which a mechanism is balanced (or unbalanced) is directly related to the "degree" of central symmetry of the pattern formed by the cranks. The objective of this research is to identify the self-balancing conditions for mechanisms with a constant equivalent moment of inertia with four and three operating elements. It is shown that the star patterns formed by the cranks of mechanisms with a constant equivalent moment of inertia that have more than two operating elements are indeed centrally symmetric. Such mechanisms are balanced. It was found that, in a balanced mechanism with a constant equivalent moment of inertia, at least three operating elements perform linear oscillations.
Keywords
Oscillations, phase, inertial power, self-balancing, central symmetry.
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