JPS5968647A - Fatigue testing device - Google Patents

Abstract

PURPOSE:To give a wide-range load with a simple structure to perform measurement, by generating the repeated load given to a test piece by an electromagnetic driving mechanism. CONSTITUTION:One end 1A of an expanding and contracting test piece 1 is fixed to a fixed base 2, and the other end 1B is attached to an output end 4 of an electromagnetic driving mechanism 3. An oscillator 5 is provided in the driving mechanism 3, and an output of the oscillator 5 is amplified in an amplifier 6 and is supplied to a coil 7, and a diaphragm of a speaker 8 is vibrated by the supplied exciting current of the coil 7. The output end 4 attached as one body together with the diaphragm is moved back and forth in accordance with the exciting current, and this motion is allowed to act upon the test piece 1, and the displacement of the output end 4 is detected by a displacement measurer 9.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fatigue testing apparatus, and particularly to an apparatus for carrying out fatigue tests on thin plate materials such as metal plates as test pieces.

In a power solar cell device, a plurality of solar cell elements are usually electrically connected in series and parallel to obtain a desired output.
- It is used in In order to electrically connect such solar cell elements, interconnectors made of metal plates are used.

When a solar cell is used as a power source for an artificial satellite, the interconnector including the solar cell will be exposed to a wide temperature range of about +100° C. to -150° C. in the space environment. Under such an environment, the interconnectors that connect the solar cell elements are subject to repeated expansion/contraction or bending loads, which may cause fatigue failure of the interconnectors. Fatigue failure of the interconnector impairs the functionality of the solar cell device, and has a major impact on equipment that uses solar cells as a power source, leading to a situation where the equipment cannot achieve its intended purpose.

In order to prevent the above situation from occurring, it is necessary to conduct a fatigue test in advance by subjecting the metal plate of the interconnector to a load that is expected to cause expansion, contraction, or bending, and to confirm in advance that it has the necessary durability. There is. One possible alternative test method would be an expansion/contraction test using temperature cycles, but this poses problems in terms of time and cost, so accelerated testing methods are generally used.

BACKGROUND ART Conventionally, a method of mechanically creating and applying a 0:1 load has been used as a device for fatigue testing by repeatedly applying a load to a metal piece. For example, a stretching or bending fatigue test is performed on a test piece using a mechanism that uses a cam or the like to convert the rotational rhythm of a motor into a linear reciprocating motion and adjusts the stroke to a required stroke. However, the fatigue test equipment that generates a load according to (1) above has the following drawbacks.

b) The extension/contraction stroke required for the test usually covers a wide area ranging from several millimeters to several millimeters, and it is extremely difficult to obtain a particularly small area (for example, 100 μm or less) 'C' by external mechanical control such as a cam. is difficult, and accuracy is significantly compromised.

In a mechanical load generating mechanism such as a cam, it is difficult to cut a wide range of expansion and contraction strokes with one device, and in order to change the expansion and contraction stroke, high precision is required according to the desired stroke. Since elements such as cams must be manufactured and replaced each time, the device becomes extremely expensive. The present invention provides a one-gauge fatigue testing device for thin plate materials that can continuously change the expansion/contraction or bending stroke over a wide range depending on the amount of force generated. The present invention will be explained in detail by giving examples below.

In the figure, 1 is a stretchable test piece, for example, a metal plate for electrically connecting solar cell elements mounted on an artificial satellite, and is therefore processed into a form that will actually be used as a connection part. . One end IA of the test piece 1 is fixed to a fixing base 2, while the other end IB is attached to an output end 4 of an electromagnetic drive mechanism 3.

The electromagnetic drive mechanism 3 is a mechanism for applying a load such as stretching or bending to the test piece 1 at a desired period and amplitude, and is provided with an oscillator 5 that generates, for example, a sine wave, and the output of the oscillator 5 is The signal is amplified via an amplifier 6 and then supplied to a coil 7. The excitation current supplied to the coil 7 vibrates the so-called diaphragm of the speaker 8, and the output end 4, which is integrally attached to the diaphragm, responds to the waveform and amplitude of the excitation current. - to make a reciprocating motion. However, since the ID test piece 1 is attached to the output end 4, the reciprocating motion taken out due to the conversion acts on the test piece 1.
The displacement of the output end 4 due to the addition of the test piece 1 is detected. A displacement measuring device 9 is provided to measure the displacement of the output end 4, and the displacement of the output end 4 is detected and inputted to the next stage expansion/contraction number recorder 10, so that the number of repetitions of one expansion/contraction test is one measurement. be done.

If the test piece 1 breaks due to fatigue, or if a defect occurs even if it does not break, the displacement signal detected at the output end 4 changes, making it possible to detect an abnormality in the test piece.
You can learn about the characteristics of fatigue tests.

According to the electromagnetic drive mechanism described above, by controlling the waveform and amplitude of the excitation current supplied to the coil 7, it is possible to adjust the stroke that affects the test specimen 1, and it is also possible to change it continuously. The speed of expansion and contraction (the number of strokes per unit time) can also be easily set (continuously) by changing the frequency of the excitation current. The method is not limited to , and can also be applied to the evaluation of similar thin sheet monthly interest rates.

As described above, according to the present invention, in an apparatus for performing a fatigue test on a thin plate, a load over a wide range can be changed with a simple structure by creating a reciprocating load on a test piece using an electromagnetic drive mechanism. Tei! 111 constant, the mechanism for changing measurement conditions is significantly simplified compared to conventional devices, and highly accurate test results can be obtained, making it possible to obtain a test device that is highly profitable.

[Brief explanation of drawings]

1. Test piece 2. Fixed 3. Electromagnetic drive mechanism 4. Output end
5° pounder 6. Amplifier 7 Coil 8゛Speaker

Claims (1)

[Claims] (2) An oscillator that forms an output signal of a desired frequency, an electromagnetic transducer that converts the oscillator output into a position displacement output, and a test piece that is coupled to the electromagnetic transducer and has one end circumferentially circumferentially connected to the other end of the test piece. A fatigue testing device comprising a test piece holder that is displaced in response to a positional displacement output of an electromagnetic transducer, and a displacement measuring device that detects the displacement of the test piece holder.