JPH02186233A - Vibration testing machine - Google Patents

Abstract

PURPOSE:To prevent a distortion of an output waveform minimizing the generation of a couple by arranging a plurality of vibrating machines which are arranged radially on the same plane with a vibration base with a vibration neutral so that intersection of the center lines thereof coincides with the center of the vibration base and the center of gravity of a moving part and a pre-force attaching mechanism. CONSTITUTION:Eight vibrating machines 1a are connected to a vibration base 022 with a square plane shape so that the center of gravity GT of the base 022 passes through the center line of the vibrating machine 1a. A pre-force type tensile force f1 is applied with horizontally vibrating machines 1a so that it is generated to attract the base 022 with vibration neutral while cancelling these combined attracting forces to zero. This can minimize a couple tending to generate a yawing motion.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a vibration testing machine.

[Conventional technology]

For example, as shown in the 10th factor plane diagram, the vibrating table 022 of a square plane is arranged parallel to the There is one that is excited by the two horizontal vibration exciters 023.

Here, Fl is the excitation force of the vibration exciter, GT is the center of gravity of the vibration table, 11 is the length of the perpendicular line drawn from the center of gravity GT of the vibration table to the line of force of the vibration exciter, and x, y, and z are the XIs, Y axis,
It is the Z axis.

Furthermore, as shown in the 11th factor diagram, the vibration table 022 is
In some cases, the vibration is excited in the X-axis direction by two vibration exciters 023 arranged in parallel in the axial direction, or the vibration is excited by two vibration exciters 023 arranged in parallel in the Y-axis direction. Here, 024
is the specimen, and Go is the composite center of gravity of the weight of the movable parts such as the vibration table, the specimen, and the vibrator.

Furthermore, as shown in the 12th factor diagram, the vibration table 022
Vibration is performed in the X-axis direction by two pairs of left and right vibration exciters 023 arranged parallel to the axial direction, or vibration is excited in the Y-axis direction by two pairs of front and rear vibration exciters 023 arranged parallel to the Y-axis direction. Some things are done.

As shown in the 13th factor diagram, the vibration table 022 is vibrated in the X-axis direction by a pair of left and right vibrators 023 facing each other with different lines of action in the X-axis direction, and is also acted on in the Y-axis direction. There is also one that is excited in the Y-axis direction by a pair of front and rear vibration exciters 023 facing each other with different lines.

However, in these arrangement guidelines, the line of action of the vibration exciter 023 is located at the center of gravity G of the vibration table, as shown in Figures 1O to 12.
The leg length of the perpendicular line is deviated from T by 11, and the vibration table 02
2. Specimen 024. The center of gravity GO of the weight of movable parts such as the vibrator 023 is generally not on the X-Y plane, and the center of gravity GO
Since the vertical projection point on the X-Y plane is often eccentric from the origin O of the X-Y plane, the
When an unbalance occurs in the excitation force F1 between the vibration exciters for the axis or the Y-axis, and focusing on the vibration table 022, ΣFtXlt
(N is the total number of horizontal shakers) acts on the vibration table 022, and the X-axis.

Rotational motion around the Z-axis (hereinafter referred to as yawing motion) perpendicular to the X@Y-axis is added to the Y-axis or X-axis/Y-axis translational excitation motion, and this tendency is remarkable in the one shown in FIG.

Therefore, these devices have the following drawbacks.

(1) In the case of FIG. 10, it is necessary to provide a guide structure that allows the vibration table 022 to move only in the excitation direction.

(2) In the case of FIGS. 11 to 13, the structure of (1) above cannot be used.

(3) In the case of Figure 10.11.13, the vibration exciter 0
When a mechanism with a gap is adopted in the joint between the vibration table 23 and the vibration table 022, the required output waveform is changed due to discontinuity and nonlinearity during reciprocating motion due to the influence of the clearance.
Distortion occurs in the acceleration waveform of No.2.

[Problem to be solved by the invention]

The present invention was proposed in view of these circumstances, and
The purpose of the present invention is to provide a highly accurate vibration testing machine in which yawing motion is less likely to be derived from excitation motion, and in which distortion does not occur in the output waveform even if there is a gap in the joint between the vibrator and the vibration table. .

[Means to solve the problem]

To this end, the present invention provides a vibration tester in which a vibration table on which a specimen is attached is reciprocated by a vibrator.
A plurality of vibration exciters are arranged radially on a plane, and the intersection of their center lines coincides with the center of gravity of the vibration table or the center of gravity of the entire movable part in the neutral vibration state, and The present invention is characterized by comprising a pre-force applying mechanism that applies a pre-force to the vibration table that attracts or presses each other and makes the resultant force zero.

[Effect]

The vibration exciter is installed on the vibration table in a radial manner on a flat surface, and the center of the radial line coincides with the center of gravity of the vibration table or the center of gravity of the entire movable part in the neutral state of vibration, so that the excitation force is reduced. Even if unbalance occurs, the generation of force couples that cause yawing can be minimized. In addition, each of the above-mentioned vibrators is equipped with a pre-force applying mechanism that attracts the above-mentioned vibration table in the neutral state of vibration, and the resultant force of these forces becomes zero. Even if there is a gap between the joint between the vibration exciter and the vibration table, it is possible to perform vibration without distortion in the output waveform, which eliminates the influence of the gap, and eliminates the couple generated in the vibration table due to disturbance. be able to.

〔Example〕

One embodiment of the present invention will be explained with reference to the drawings.
The same numbers as in Fig. 13 indicate the same members as in the same figure. First, in the first factor plane view and the side view in Fig. 2, 1 is a vibration table 022 with a square planar shape and eight vibrator exciters. 1a is a vibration tester that is connected radially and the center line of the vibrator 1a passes through the center of gravity GT of the vibration table 022; 2 is a static pressure bearing that supports the horizontal movement of the vibration table 022; This is a 100-type tensile force that is generated by the vibrator 1a to attract the vibrating table 022 in the neutral state of vibration, and whose combined attractive force becomes zero.

Next, in the partially enlarged vertical cross-sectional views of FIGS. 3 to 5, 3 is a fixed end joint protruding from the fixed end 4, and 5° and 6 are vibrating exciters protruding from the base end and tip of the vibrator 1a, respectively. Machine joints, 7 and 8 are the cylinder chamber and preload chamber of the vibrator 1a, 9 is the air opening in the cylinder bored at the base end and center of the vibrator 1a, respectively, 10 is the both ends of the vibration table 0220 11 is a hydraulic pump, 12 is an oil tank, 13 is a servo valve, and 14 is an air accumulator attached to the vibrator 1a.

CI, C2, P, and T are boats bored in the servo valve 13, respectively, and δ is the gap between the connection between the vibration exciter joint 7 and the vibration table joint 8.

In such a device, as shown in Fig. 1, the horizontal vibrator 1a is arranged radially, and its center point is aligned with the center of gravity GT of the shaking table in the neutral state of excitation, so that the The leg length 11 of the perpendicular line can be minimized. Therefore, even if an imbalance occurs in the excitation force F1 of each exciter 1a during excitation, the couple ΣFiX11 that generates the yawing motion can be minimized. I can figure it out.

In addition, as shown in FIG. 3, when the vibration table 022 is in the neutral state of vibration, the air accumulators 14 of the left and right vibration exciters 1a cause the vibration table 022 to
A tensile force f1 due to a preload is applied to the left and right sides, respectively, and then, as shown in FIG. At the same time, by returning the hydraulic pressure from the cylinder chamber 7 of the left vibrator 1a to the oil tank 12 using the servo valve 13 on the left side, even if the vibration table 022 is moved to the right as shown by the arrow 15, the pressure between each joint is maintained. The connection state can maintain the initial state shown in FIG. 3, and therefore, even if there is a gap δ between each joint, the effect of the gap δ can be eliminated by performing the above-mentioned attractive vibration.

Note that the same effect can be obtained in the case of FIG. 5 in which the vibration table 022 is vibrated to the left.

In addition, as shown in FIG. 6, in addition to the excitation force Fl and F2°, KF3. When F4 is applied, a couple is generally generated due to the play between the vibrator and the vibration table, but even in such a case, by employing a preliminary reference means, as shown in the figure, Generation of couples can be prevented.

Next, in the first modification of the vibration testing machine 1 shown in the seventh factor diagram, 16 is a vibration testing machine in which four vibration exciters 1a are connected radially to a vibration table 022, and the effect is that the vibration In addition to being substantially the same as that of the testing machine 1, it has the advantage that the number of vibration exciters 1a can be reduced.

Furthermore, in the second modification of the vibration tester 1 shown in the 8th factor diagram, 17 is a vibration table 18 having a circular planar shape.
A is a vibration testing machine in which eight units are connected in a radial manner, and its operation and effect are substantially the same as those of the vibration testing machine I, and the feature is that there is a large degree of freedom when installing the specimen 024 on the vibration table 18. be.

In addition, in a third modification of the vibration testing machine 1 shown in the side view of FIG. Its operation and effect are substantially the same as those of the vibration testing machine 1, and it also has the advantage of being able to perform vertical vibration.

Note that the best effects can be obtained when the center of gravity GO of the entire movable part coincides with the intersection of the center lines of the plurality of radially attached vibrators 1a.

According to the devices of these embodiments and modified examples, the following effects can be achieved.

(1) The vibration exciters are installed radially on the vibration table, and the intersection of the center lines of each vibration table coincides with the center of gravity of the vibration table, so even if the excitation force is unbalanced, the yaw The generation of force couples that induce motion can be minimized, and a highly accurate vibration testing machine can therefore be obtained.

(2) Each vibration exciter installed radially on the vibration table,
A pre-force applying mechanism is installed that pulls or pushes the vibration table in the neutral state of excitation, and the resultant force of these forces becomes zero, so even if there is a gap between the joint between the vibration exciter and the vibration table, It is now possible to excite without causing distortion in the output waveform that eliminates this influence, and it also becomes possible to eliminate the couple force generated in the vibration table due to the play in the joint, making it possible to use a high-precision vibration tester Obtainable.

〔Effect of the invention〕

In short, according to the present invention, in a vibration testing machine in which a vibration table on which a specimen is attached is reciprocated by a vibrator, the vibration table is arranged radially on a plane, and the intersection of the center lines is in the neutral state of vibration. A plurality of vibration exciters that coincide with the center of gravity of the above-mentioned vibration table or the center of gravity of the entire movable part, and a pre-force such that the above-mentioned vibration tables are attracted or pressed against each other in the neutral state of vibration, and the resultant force thereof becomes zero. By providing the above-mentioned pre-loading mechanism for the vibration table, yawing motion is less likely to be derived from the excitation motion, and even if there is a gap in the joint between the vibration exciter and the vibration table, distortion will not occur in the output waveform. The present invention is industrially extremely useful because it provides a highly accurate vibration testing machine.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing one embodiment of the present invention, and Fig. 2 is a plan view showing an embodiment of the present invention.
3 is a side view of the figure, FIG. 3 is a vertical sectional view showing a neutral state along line 1-1 of FIG. 1, and FIG. 4 is a side view of the figure. Figure 5 is a vertical sectional view showing the vibration table in Figure 3 vibrating to the right and left, respectively, and Figure 6 is the elimination of the couple by applying a child attraction to the vibration table in Figure 1. Explanatory diagrams showing the action, Figures 7 and 8 are the first part of diagram s1, respectively.
The same plan view showing the modified example and the second modified example, FIG. 9 is the first
FIG. 1O, FIG. 11, FIG. 12, and FIG. 13 are plan views showing different known vibration testing machines, respectively. 1... Vibration tester, 12L... Vibrator, 2... Static pressure bearing, 3... Fixed end joint, 4... Hard, 2 ends, 5,
6... Vibrator joint, 7... Cylinder chamber, 8...
Preload chamber, 9... Air discharge port, 10... Vibration table joint,
Engineering 1...Hydraulic pump, 12...Oil tank, 13...
・Servo valve, 14...Air accumulator, 15...Arrow, 16
．． 1? ... Vibration tester, 18... Shaking [stand, 19...
・Vibration tester, 20... Vertical vibrator, 022... Vibration table, 024... Specimen, CI...
CI boat, C2...C2 port, Fi...excitation force, fl...tension force, Go...center of gravity of the entire moving part, G
T...Center of gravity of the shaking table, 11...Length of the perpendicular leg, 0
...Origin, P...P boat, T...T boat, X
...X axis, Y...Y axis, 2...Z axis, δ...gap, Fig. 5

Claims (1)

[Claims] In a vibration testing machine in which a vibration table on which a specimen is attached is reciprocated by a vibrator, the vibration table is arranged radially on the same plane as the vibration table, and the intersection of the center lines is the center of gravity of the vibration table or A plurality of vibrators aligned with the center of gravity of the entire movable part, and a pre-force applied to the vibrating table so that the vibrating table is attracted or pressed against each other in the neutral state of vibration, and the resultant force thereof becomes zero. A vibration testing machine characterized by comprising a mechanism.