JPH02229940A - Rotary body and regulation method for dynamic unbalance thereof - Google Patents

Abstract

PURPOSE:To facilitate secondary microadjustment control of a balance weight by a method wherein the given number of balance weights are disposed with a time in positions in a plurality of concentric recessed and protrusion parts, having difference radii, on the center of a rotary shaft and formed on the upper surface of a rotary body. CONSTITUTION:A dynamic unbalance is regulated as a test by a dynamic unbalance tester is applied on a rotary body 1. When a dynamic unbalance position is detected, a proper weight of a balance weight 5 is disposed in the dynamic unbalance position of an outer annular recessed part 2a. When the rotary body 1 is set to the dynamic unbalance tester again for rotation, it is detected that a dynamic unbalance is eliminated or a slight one remains. In order to remove an unbalance, a different balance weight 6 is disposed in a position in an inner annular recessed part. In which case, with the decrease in a distance to the inner annular recessed part from the rotary shaft compared with that to an outer annular recessed part 2a therefrom, the weight of a balance weight can be increased to a high value. Namely, microadjustment control is always heretofore difficult to make, but by increasing the weight of the balance weight 6 to a high value, a dynamic unbalance can be high-efficiently regulated by means of a total weight obtained by adding it to the already- arranged balance weight 5.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a rotating body, and more specifically, to a configuration for eliminating rotational unbalance or imbalance of a rotating body. (Prior art) Rotational unbalance (hereinafter referred to as dynamic unbalance) occurs during operation due to imbalance in the structure, shape, etc. of the rotating body. As a result, vibrations, noise, etc. were generated in the rotating body and the equipment to which it was attached, causing problems with the rotating body and equipment. In the first place, the dynamic unbalance of a rotating body is caused by an unbalanced amount of centrifugal force F, as shown in Figure 4. If the distance is r and the angular velocity is ω, it can be expressed by the formula F=mrω2. When performing dynamic unbalance adjustment, a balance weight with the same mass m' as the amount of unbalance m is placed at point A (Fig. 4) at a position symmetrical to the order n of this centrifugal force F. This makes it possible to eliminate dynamic unbalance.
Therefore, in the conventional rotating body, as shown in FIG. The dynamic unbalance position was determined using a testing machine, and an appropriate amount of balance weight 4 was attached to this dynamic unbalance position, for example, at an appropriate position in the annular groove 2, in order to remove the dynamic unbalance. (Problem to be solved by the invention) In the conventional example described above, when performing dynamic unbalance adjustment,
In order to improve rotation accuracy, it is necessary to provide the same amount of balance weight m' for the unbalance amount m shown in FIG. However, in order to adjust so that m = m',
It is necessary to repeatedly carry out minute adjustments, which is extremely cumbersome, requires special skill, and has problems such as poor adjustment efficiency. The present invention aims to eliminate the aforementioned problems. (Means for Solving the Problems) The present invention provides the following means to achieve the above object.
That is, by providing a plurality of annular concave portions or convex portions concentric with the rotating shaft on the upper surface of the rotary body, and placing predetermined balance weights at predetermined positions of each of these four portions or convex portions, the dynamic unbalance of the rotary body can be reduced. First, an appropriate amount of balance weight is placed in a concentric annular concave or convex portion with a large radius, and then a predetermined amount of balance weight is placed in a concentric concave or convex portion with a small radius in order to completely adjust the dynamic unbalance. In this method, the dynamic unbalance of the rotating body is adjusted by the total mass of the two balance weights. (Function) In the present invention, a plurality of concentric annular recesses or protrusions are provided on the upper surface of the rotating body around the rotation axis, and a balance weight is attached to the concentric annular recesses or protrusions with a large radius to correct the rough dynamic imbalance. First adjustment is performed by this, and then, in order to perform delicate second adjustment, dynamic unbalance is performed by placing a predetermined amount of balance weight in a concentric annular concave or convex portion with a small radius. In other words, as mentioned above, it is expressed by the equation of centrifugal force F=mrω2, where centrifugal force F is the unbalance amount m
Since the distance #r is proportional to the square of the angular velocity ω, if the same centrifugal force is obtained at a constant angular velocity, if the distance r is halved, the amount of unbalance can be doubled. Extremely efficient unbalance adjustment is possible by placing balance weights on the four concentric annular parts or the convex parts. (Example) An example of the present invention will be described below with reference to the attached drawings. FIG. 1 is a perspective view of a first embodiment of the present invention. 1 in the diagram
is a rotating body, 2a is an outer annular recess with a large radius provided concentrically with the rotating shaft 3, and 2b is an inner annular recess with a small radius that is concentric with the four annular portions 2a. Reference numeral 5 designates a balance weight for adjusting the first-order dynamic unbalance provided within the outer annular recess 2a, and reference numeral 6 represents a balance weight for adjusting the second-order dynamic unbalance provided within the inner four portions 2b. The distances from the rotating shaft 3 to the outer annular recess 2a and the inner annular four parts 2b are respectively Rl. R2, the rotating body l is rotating at an angular velocity ω, and the rotating body dynamic unbalance has not been adjusted. The dynamic unbalance is adjusted by subjecting this rotating body l to a dynamic unbalance testing machine. When the dynamic unbalance position is determined by the dynamic unbalance tester, an appropriate amount of balance weight 5 is placed at the dynamic unbalance position in the outer annular recess 2a. Next, when the rotating body 1 is rotated again by the dynamic unbalance tester, it is found that the dynamic unbalance is largely eliminated or remains slightly.
Therefore, in order to eliminate this unbalance, another balance weight 6 is placed at a predetermined position within the inner annular recess. As mentioned above, compared to the outer annular four portions 2a, the shorter the distance from the rotation axis, the greater the amount of balance weight can be taken. In other words, in the conventional example, there is a difficulty in constantly having to make minute adjustments, whereas by increasing the amount of balance weights 6, dynamic unbalance can be effectively balanced with the total amount of balance weights 5 already arranged. can be adjusted. FIG. 3 illustrates a second embodiment of the invention. A concentric outer annular protrusion 7a and an inner annular protrusion 7b are provided on the upper surface of the rotating body 1 with the rotation axis as the center, and predetermined amounts of balance weights 8 and 9 are arranged at predetermined positions on the side walls of the protrusions 7a and 7b. This is what I did. The dynamic unbalance of the rotating body can be adjusted using the same principle as in the first embodiment. (Effect) A plurality of concentric annular concave portions or convex portions with different radii are provided on the upper surface of the rotating body around the rotation axis, and a predetermined amount of balance weight is placed at a predetermined position of each of these concave portions or convex portions over time. This overcomes the difficulty of making secondary minute adjustments to the balance weight at one location, as in the conventional case, and makes it possible to make extremely efficient adjustments.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of a rotating body according to the present invention. FIG. 2 is a cross-sectional view of a state in which the eight lance weights shown in FIG. 1 are not provided. Figure 3 is a perspective view of another embodiment. Figure 4 is a schematic diagram showing the relationship between centrifugal force of a rotating body, unbalance amount, distance, and angular velocity. Figure 5 is a perspective view of a conventional rotating body. DESCRIPTION OF SYMBOLS 1...Rotating body, 2a...Outer annular recess, 2b...
Inner annular recess, 3... Rotating shaft, 5.6... Balance weight, 7a... Outer annular protrusion, 7b... Inner annular protrusion, 8, 9... Balance weight. Application
Person Kobal Electronics Co., Ltd. Agent Patent Attorney Eiji Kobayashi 1 Figure 3 Figure 3... 1'' Axis of rotation 5, 6...Bara Tsukaeito 2nd figure 7a...Ge L cloth 9 syndrome J round convex right side 8,9...Balun 2 quaight 7b...Inner Iri'4 4 Anal convex Ya

Claims (1)

[Claims] 1. A plurality of concentric annular recesses having different radii are provided on the upper surface of the rotating body around the rotation axis, and a predetermined amount of balance weight is disposed at a predetermined position in each of these recesses to achieve rotational movement. A rotating body characterized by adjusting unbalance. 2. The rotating body according to claim 1, wherein an annular protrusion is provided in place of the concentric annular recess, and a predetermined amount of balance weight is disposed at a predetermined position on a side wall of the protrusion. 3. A plurality of concentric annular recesses with different radii are provided on the top surface of the rotating body around the rotation axis, and first an appropriate amount of balance weight is placed at a predetermined position within the annular recess with a large radius, and then an appropriate amount of balance weight is placed at a predetermined position within the annular recess with a large radius. A method for adjusting dynamic unbalance of a rotating body using the masses of the two balance weights, which are arranged at predetermined positions in a small annular recess. 4. The rotating body dynamic unbalance adjustment method according to claim 3, wherein an annular convex portion is provided in place of the concentric annular concave portion, and appropriate amounts of balance weights are sequentially arranged at predetermined positions on the side wall of the convex portion.