JPH0293380A - Measurement start system of measuring apparatus - Google Patents

Abstract

PURPOSE:To enhance operability without deteriorating probe operability by detecting the contact of the sensor part of a probe with an object to be measured to start a measured data processing means. CONSTITUTION:When the output of a probe 1 is changed on a higher side by the contact of the leading end of the probe 1 with the terminal of an object to be measured, the output of a comparator 4B comparing the output of a minute difference voltage circuit 2 with that of a reference voltage circuit 3 is reversed to L and the input of a microprocessor 7 becomes L by a time constant circuit of a resistor R7 and a condenser C. By this mechanism, the measured data processing means of a measuring unit 5 is started by the microprocessor 7. When the contact output of the probe is changed on a lower side, the same processing is performed through a comparator 4A and it is unnecessary to start the measuring unit by a button and measuring operability is enhanced without deteriorating probe operability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a measurement start method for a measuring device that measures voltage and the like by bringing a probe into contact with a measurement target.

(Prior Art) Conventionally, in this type of measuring device, a start switch that generates a start signal to activate the measuring circuit and start measurement is usually provided in the housing of the device, etc. . Therefore, when operating the start switch while holding the probe and touching the object to be measured, it is necessary to extend the hand to the start switch, resulting in poor operability. Additionally, there are methods that have a start switch on the probe, but with this method the probe becomes larger and a separate connection wire for the start switch is required, increasing the number of connection wires between the probe and the measuring device. There was a drawback to that.

(Problems to be Solved by the Invention) As mentioned above, in the measurement start method of the conventional measuring device,
The system in which the start switch is provided in the housing or the like has the disadvantage of poor operability since the user must extend his or her hand to the start switch to operate it. In addition, in order to avoid this drawback, the method of providing the start switch on the probe increases the size of the probe and increases the number of connection wires connecting the probe and the measuring device, which deteriorates the operability of the probe. There was a drawback. SUMMARY OF THE INVENTION Therefore, the present invention aims to eliminate the above-mentioned drawbacks, and provides a measurement start method for a measuring device that can improve the operability at the start of measurement without deteriorating the operability of the probe. .

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a measuring device in which data obtained by bringing a sensor portion of a probe into contact with an object to be measured is measured and processed by a measurement data processing means. detecting means for detecting whether or not the probe has touched the object to be measured from a voltage change in the sensor section of the probe; and a control means for activating the measurement data processing means, and while the control means is activating the measurement data processing means, the detection means detects that the connection between the sensor section of the probe and the object to be measured is broken for a certain period of time or more. If this is detected, the data obtained from the probe is invalidated.

(Function) In the measurement start method of the measuring device of the present invention, when the detection means detects contact of the sensor section of the probe with the object to be measured, the control means causes the measurement data processing means to process the data obtained from the probe. Start it up and start measurement. Further, while the control means is activating the measurement data processing means, when the detection means detects that the connection between the sensor section of the probe and the object to be measured is broken for a certain period of time or more,
Misjudgment is avoided by invalidating the data obtained from the probe.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a measuring device to which the measurement starting method of the measuring device of the present invention is applied. 1 is a probe whose tip touches the object to be measured, 2 is a resistor R1, R2
, R3 and R4 connected in series, 3 is a reference voltage circuit formed by connecting resistors R5 and R6 in series, 4A
, 4B is a comparator that compares the input voltage with a reference voltage,
5 is a measurement unit that processes the signal input from probe 1 and generates 1q of measurement data, and 6 is a measurement unit that processes the signal input from probe 1 and generates 1q of measurement data.
A flip-flop detects when the sensor moves away from the measurement object and becomes non-contact, and 7 is a microprocessor (MPtJ) that controls the measurement operation.

Note that the resistor R7 and the capacitor C form a time constant circuit.

Next, the operation of this embodiment will be explained. The measurer brings the tip of the probe 1 into contact with a terminal or the like of the object to be measured. As a result, the output voltage of the probe 1 becomes higher or lower than when it is not in contact.

Here, in the minute difference voltage circuit 2, the resistance value of each resistor is set to R1-
It is assumed that R3 and R2-R4 are selected, and the resistance value is selected so that R1pR2.

Further, it is assumed that the resistance value of the reference voltage circuit 3 is selected to be R5-R6. Therefore, during the period when the probe 1 is not in contact, the voltages at points a, b, and c in the figure are va, yb, and VC, and va>Vb>Vc. Further, the values of each of the resistors are selected so that the difference between va and VC is small.

Further, point a is connected to the non-inverting input terminal of comparator 4A, and point 0 is connected to the inverting input terminal of comparator 4B.

Therefore, during the period when the probe 1 is not in contact, both the outputs of the comparators 4A and 4B are at a high level, and the voltage Vd at the point d is also at a high level. This voltage Vd is MPU7
The MPU 7 does not activate the measurement unit 5 while the voltage Vd is at a high level. In this state, if the probe 1 is brought into contact with the object to be measured and the output voltage of the probe 1 changes to a higher side, Vc >
Vd, and the output of the comparator 4B becomes low level. Therefore, the voltage vd changes to a low level after a time delay determined by the time constant circuit of the resistor R7 and the capacitor C, and the MPU 7 detects this and starts the measurement unit 5. Also, by bringing the probe 1 into contact with the object to be measured,
If the output voltage of probe 1 changes to the lower side, va
As a result, the output of the comparator 4A becomes low level. Therefore, Vd changes to a low level after a time delay determined by the time constant circuit, and the MPLI 7 detecting this changes to start the measurement unit 5. The MPU 7 activates the measurement unit 5 and simultaneously clears the flip-flop 6. When activated, the measurement unit 5 processes the data input from the probe 1 and retains this data. When the measurement unit 5 completes data input and processing, it outputs a completion signal to the MPU 7 to notify the MPLJ 7 of the completion of the measurement. When the MPU 7 learns of the end of the measurement, it checks that the Noritsubu flop 6 is not set, reads the data from the measurement unit 5, and then reads the data from the measurement unit 5.
Determine whether the measurement target is good or bad from the read data. However, if the flip-flop 6 is set, the MPtJ7 determines that the probe 1 has moved away from the object to be measured during measurement, stops the operation of the measurement unit 5, and returns to monitoring the voltage d. Repeat the measurement operation.

FIG. 2 is an operation flowchart of the MPU 7. In step 201, it is monitored whether or not the probe 1 has contacted the object to be measured.
After clearing the flip-flop 6 in step 203, the measurement unit 5 is activated. Step 204
Then, it waits for an end signal from the measurement unit 5, and when the end signal is received, the flip-flop 6 is turned on in step 205.
A contact failure of the probe 1 is determined based on whether or not is set. If there is a contact failure, the process returns to step 201; otherwise, the process proceeds to step 206. In step 206, the measurement data is read from the measurement unit 5, and it is determined whether the object to be measured is good or not, and the process ends.

Here, the flip-flop 6 is connected to the MPU at the start of measurement.
7, so it remains cleared if the probe 1 does not move away from the object to be measured during measurement.

However, if the probe 1 separates from the object to be measured during measurement, the comparator 4A.

Both outputs of 4B become high level, and from the time when they become high level, the flip-flop 6 is repeatedly set by the voltage Vd for a certain period of time determined by the time constant circuit of the resistor R7 and the capacitor C.

Therefore, if the flip-flop 6 is activated, it can be determined that the probe 1 has left the object to be measured during the measurement period. However, if the change in the output voltage of the probe 1 is within a certain period of time determined by the time constant circuit, the Noribu flop 6 is not set. This prevents the output voltage change of the probe 1 from erroneously determining that the probe 11 is not in contact.

According to this embodiment, the MPU 7 determines whether or not the probe 1 has made contact with the minute difference voltage circuit 2 and the comparators 4A and 4B.
When the probe 1 makes contact, the measurement unit 5 is activated and the measurement process of the data obtained from the probe 1 is started. The device can be prompted to start measurement, and the operability of the device can be significantly improved. Moreover, probe 1 can be the same size as before,
The operability of the probe 1 is not impaired. In addition, if the probe 1 becomes non-contact during measurement, the flip-flop 6
By detecting this, it is possible to eliminate data errors due to poor contact of the probe 1 during measurement.

[Effects of the Invention] As described above, according to the measurement start method of the measuring device of the present invention, the operability at the start of measurement can be significantly improved without impairing the operability of the probe.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a measuring device to which the measurement starting method of the measuring device of the present invention is applied, and FIG. 2 is an operation flowchart of the microprocessor shown in FIG. 1. 1...Probe 2...Minute difference voltage circuit 3...Reference voltage circuit 4A, 4B...Comparator 5...Measuring unit 6...Flip-flop 7...Microprocessor (MPU) agent Patent Attorney Noriyuki Yamashita

Claims (2)

[Claims] (1) In a measuring device in which data obtained by bringing a sensor section of a probe into contact with an object to be measured is processed by a measurement data processing means, it is determined whether or not the sensor section of the probe has contacted the object to be measured. A detection means for detecting a voltage change in a sensor section of a probe, and a control means for activating the measurement data processing means when contact of the sensor section with an object to be measured is detected by the detection means. A measurement start method for a measuring device characterized by: (2) While the control means is activating the measurement data processing means, if the detection means detects that the connection between the sensor part of the probe and the object to be measured is broken for a certain period of time or more, the data obtained from the probe is invalidated. Claim 1 characterized in that
Measurement start method of the described measuring device.