JP2741723B2 - Material testing machine load measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load measuring device of a material testing machine particularly suitable for measuring a peel load.

[0002]

2. Description of the Related Art Conventionally, when measuring the bonding strength using a material testing machine, the load applied to a test piece by a load device is detected by a load detector such as a load cell, and a load signal is A / D. The data is digitized by the converter and read into the CPU, the change in the load is observed by the CPU, and the upper limit load and the lower limit load are measured from the data. FIG. 6 shows a characteristic diagram of the load measured in this manner.

[0003]

When the load is measured as described above, the sampling cycle A (ms) is applied to the load signal indicated by the solid line as shown in FIGS.
Therefore, there is a problem that the true upper limit load and the lower limit load at the interval of the sampling time cannot be measured.

[0004]

In order to solve the above problems, the present invention employs the following configuration. That is, the load measuring device of the material testing machine according to the present invention includes a reading unit that reads a load signal from a load detector at a predetermined sampling timing, a peak hold circuit that stores a peak value and a valley value of the load signal, and The valley hold circuit, and the peak value and the valley value held in the peak hold circuit and the valley hold circuit are read every sampling time, and then each hold circuit is reset. And an arithmetic processing circuit for measuring the lower limit load.

[0005]

The peak value and the valley value of the load signal held in the peak hold circuit and the valley hold circuit are read into the CPU while being updated at each sampling time, and are compared with the data read at the time of the previous sampling. Since the values are obtained and measured as the upper limit load and the lower limit load, the upper limit load and the lower limit load can be accurately obtained from the load signal.

[0006]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. In this load measuring apparatus 1, a load signal output from a load detector (load cell) 3 of a material testing machine 2 is output by a load amplifier 4. And input to the peak hold circuit 6, valley hold circuit 7, and multiplexer 9.
In the peak hold circuit 6 and the valley hold circuit 7,
Peak value of the load value that changes every moment until sampling time,
The valley value is stored. The stored peak value and valley value are digitized by the A / D converter 10 together with the direct value from the load detector 4 at each sampling time via the multiplexer 9 and read into the CPU 11. When the load data is read, the peak hold circuit 6 and the valley hold circuit 7 are reset by a reset signal from the CPU 11. The CPU 11 performs data processing based on the read load signal. The processed data is recorded by the printer 15 via the I / 014.

The data reading process in the CPU 11 is performed according to the processing procedure shown in the flowchart of FIG. When measuring the upper limit load, as shown in the figure, the peak value stored in the peak hold circuit 6 is read at each sampling time by setting the multiplexer 9 to the peak hold, and the multiplexer 9 is directly read.
No. Read data every sampling
To determine the maximum value of the data, and measure the maximum value as the upper limit load. Similarly, when measuring the lower limit load, the multiplexer 9 is set to valley hold, the valley value stored in the valley hold circuit 7 is read at each sampling time, and the multiplexer 9 is read directly to obtain the minimum value. Measure as the lower limit load. The load data obtained in this manner is, as shown in FIGS.
The measurement value indicated by the triangle is updated as data indicated by the circle.

When the direct value, peak hold value, and valley hold value of the load need to be measured simultaneously with respect to the circuit of the above embodiment, as shown in FIG. 17 and 18 may be provided, and data may be read in accordance with the processing procedure shown in the flowchart of FIG.

Since the load measuring device of the material testing machine measures the change in load by comparing the data at each sampling time while maintaining the peak value and valley value of the load data during the sampling cycle as described above. The upper limit load and the lower limit load can be accurately measured based on the load signal.

[0010]

As is apparent from the above description, according to the load measuring device of the material testing machine according to the present invention, the upper limit load and the lower limit load on the sample can be accurately measured at the time of the peel strength test. became.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a data reading procedure in the embodiment device.

FIG. 3 is a diagram for explaining updating of data when load data is read.

FIG. 4 is a block diagram showing a configuration of a modified example.

FIG. 5 is a flowchart showing a data reading procedure in a modified embodiment.

FIG. 6 is a characteristic diagram showing a conventional load measurement.

FIG. 7 is a diagram illustrating a problem in a conventional load measurement.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Load measuring device 2 Material testing machine 3 Load detector 6 Peak hold circuit 7 Valley hold circuit 11 CPU (comparison processing circuit)

Claims (1)

(57) [Claims] A reading means for reading a load signal from a load detector at a predetermined sampling timing; a peak hold circuit and a valley hold circuit for respectively storing a peak value and a valley value of the load signal; An arithmetic processing circuit that reads the peak value and valley value held in the valley hold circuit at each sampling time, resets each hold circuit, and detects the maximum value and the minimum value of the read data as an upper limit load and a lower limit load. A load measuring device for a material testing machine comprising: