Earlier in the article, I described the modernization of an old balancing machine with soft-bearing supports. For such machines, we install the Balanset-1A balancing device in the case of machines with two supports, and the Balanset-4 in the case of machines with more supports.
In this article, we will consider the modernization of an old balancing machine with hard-bearing supports. Their supports are made in the form of rigid plates with shaped grooves (slots). The natural vibration frequencies of these supports are significantly (at least 2-3 times) higher than the maximum rotational speed of the rotor being balanced on the machine.
Machines with hard-bearing supports are more versatile than machines with soft-bearing supports, as they usually provide the ability to balance rotors with a larger range of mass characteristics. An important advantage of these machines is also that they allow for high-precision balancing of rotors at relatively low rotational speeds, which can be within the range of 200-500 rpm and below.
Figure 1 shows a photograph of a typical balancing machine with hard-bearing supports.
From this figure, it can be seen that individual parts of the support formed by the shaped grooves have different stiffness, which under the influence of unbalance forces on the rotor can lead to deformations (displacements) of some parts of the support relative to others. (In figure 2, the more rigid part of the support is highlighted in red dotted lines, and its relatively compliant part in blue).
To measure the specified relative deformations in machines with hard-bearing supports, either force sensors or highly sensitive vibration sensors of various types, including non-contact displacement sensors, can be used.
Our company has established the production of force sensors that can be connected to the Balanset-1A and Balanset-4 devices.