JPS6091423A - Controller of vibrating stage - Google Patents

Abstract

PURPOSE:To compensate the cooperation between a specimen and a vibrator by providing a logarithm converter connected to an accleration amplitude setter, etc. at a target signal generating part and adding the signals of these converter and the signal generator to each other for conversion of exponent. CONSTITUTION:A target signal generating part 24 is provided with in addition to an acceleration amplitude setter 1 and a sine wave sweep oscillator 2, a pair of logarithm converters 1a for the acceleration and frequency signals sent from the setter 1 and the oscillator 2, a variable slope setter 1b for generated signals, an adder 1c and an exponent converter 1d. Then the setter 1 generates a fixed acceleration speed G0 which is converted into a logG0 by the converters 1a. At the same time, a frequency signal (f) sent from a transmitter 2 is also converted into a logf and furthermore into a Klogf by the setter 1b with addition of the adder 1c. Thus a signal 22 of G0f<k> is obtained through the converter 1d. Thus it is possible to produce vibrations of a fixed stroke, a fixed speed and a fixed acceleration by controlling the value of (k).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vibration table/control device, and particularly to a vibration table control device that can be applied to vibration, fatigue testing equipment, and the like.

Conventionally, in vibration table apparatuses and the like using electro-hydraulic servo actuators, sine wave sweep tests with constant acceleration have been frequently used in durability tests or resonance tests of test objects, and are also required by JI8 and the like.

As shown in Fig. 1, this is a signal that is obtained by comparing the constant set by the acceleration amplitude setting device I and the acceleration amplitude detected by the peak value detection circuit I8 in the error detector 3, and appropriately amplifying it in the variable amplifier 4. By adding these to the main acceleration input signal 2I in the adder 7, the amplitude of the output acceleration applied to the vibration exciter IK is made to match a constant input value regardless of the vibration frequency.

In FIG. 1, I is an acceleration amplitude setter, 2 is a sine wave sweep oscillator, 3 is an error detector, 4 is a variable amplifier,
5.6 is a multiplier, 7 is an adder, 8 is an error detector, 9 is a servo amplifier, 10 is a servo valve, 11 is an exciter, I21
13 is a table, 13 is a test object, 14 is a displacement detector, I5 is a displacement amplifier, 16 is an acceleration detector, 17 is an acceleration amplifier, I8 is a peak value detection circuit, 20 is a target signal generator, 2
1 to 23 are respective signals.

However, in the conventional device shown in FIG. 1 above, in reality, the dynamic characteristics of the test specimen and the vibrator system are coupled, and there is usually a frequency range in which constant acceleration cannot be vibrated. There was a drawback that durability tests or resonance tests could not be carried out satisfactorily.

The present invention was proposed to solve the above-mentioned drawbacks.
The purpose is to provide a control device for a vibration table that has the function of compensating the performance of the test specimen and the vibration exciter, and also has the function of performing sweeping vibration along an arbitrary slope straight line passing through an arbitrary point. There is something to do.

A vibration table control device according to the present invention is a vibration table control device that drives a vibration table using an excitation force according to an excitation signal output from a target signal generation section having an acceleration amplitude setting device and a sine wave sweep oscillator. , a logarithmic converter connected to the acceleration amplitude setter in the target signal generating section, a logarithmic converter and a variable slope setter connected to the sine wave sweep oscillator, and a logarithmic converter and a variable slope setter connected to the acceleration amplitude setter, respectively. an adder that adds the signal output from the logarithmic converter and the signal output from the variable slope setter; and an index converter that converts the signal output from the adder into an index. In addition to the conventional constant acceleration amplitude sweep signal oscillation and excitation functions, it also includes constant velocity and stroke amplitude sweeps, and also includes constant amplitude sweep signals of any power of the excitation frequency. An oscillator and excitation control using the oscillator can be performed.

An embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a block diagram showing the configuration of a main part of an embodiment of the present invention, and FIG. 3 is an explanatory diagram of sweep vibration according to an embodiment of the present invention.

What is shown in FIG. 2 shows the configuration of a target signal generating section 24 corresponding to the target signal generating section 20 in FIG. In addition to the sine wave sweep oscillator 2, there are two pairs of logarithmic converters 1a for logarithmically converting the acceleration signal and frequency signal emitted from them, a variable slope setting device 1b for setting the slope of the generated signal, an adder XC, and an exponential conversion. It consists of a container Id. The rest of the configuration is the same as that shown in FIG.

The operation of the above embodiment of the present invention will be explained.

In FIG. 2, an acceleration amplitude setter I generates a constant acceleration Go, and a logarithmic converter 1a converts it into JogGo. On the other hand, the frequency signal N emitted from the sine wave sweep oscillator 2 is also converted to log f by the logarithmic converter Ia, and further converted to k10g/ by the variable slope setter Zb, added to the previous signal by the adder IC, and (Go
/k) and finally passes through an index converter 1d to generate a signal 22 GOfk.

By appropriately setting the acceleration (constant) and gradient k, sweep excitation can be performed along a straight line of any gradient passing through any point within the limit performance of the device, as shown in FIG. For example, a conventional constant acceleration sweep is obtained by setting k-0, a constant velocity sweep is obtained by setting k=1, and a constant stroke sweep is obtained by setting k=1.

As described above, according to the present invention, for example, by finely adjusting the slope k near θ, it is possible to provide a function of performing constant acceleration vibration to compensate for the achievement of the test specimen and the vibration exciter.
Excitation with a constant stroke, constant speed, and constant acceleration can be performed simply by adjusting the value of k.

Further, by finely adjusting k to around 1.2, it is possible to provide a function of constant speed or constant stroke excitation that compensates for the achievement of the test specimen and the vibrator.

In addition, other excellent effects can be achieved, such as the ability to perform non-sweep vibration along an arbitrary slope straight line passing through an arbitrary point within the limit performance according to the user's needs.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a conventional example, FIG. 2 is a block diagram showing the configuration of essential parts of an embodiment of the present invention, and FIG. 3 is an explanatory diagram of sweep excitation according to an embodiment of the present invention. It is. I: Acceleration amplitude setter, 2: Sine wave sweep oscillator, Za: Logarithmic converter, Ib: Variable gradient setter, IC: Adder, 1d: Exponential converter , 24・
...Target signal generator. Applicant Sub-Agent Patent Attorney Suzue Takehikoju 113--] Koni ",-"

Claims (1)

[Claims] In a control device for a vibration table that drives a vibration table by an excitation force according to an excitation signal output from a target signal generation section having an acceleration amplitude setting device and a sine wave sweep oscillator, each of the target signal generation sections has the A logarithmic converter connected to an acceleration amplitude setter, a logarithmic converter and a variable slope setter connected to the sine wave sweep oscillator, and an output from the logarithmic converter connected to the acceleration amplitude setter. A vibration table comprising: an adder for adding a signal outputted from the variable gradient setter with a signal outputted from the variable slope setting device; and an index converter for converting the signal outputted from the adder into an index. Control device.