JP3120205B2 - Period and average current 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 period and average current measuring device for measuring a rate and an average current of a timepiece.

[0002]

2. Description of the Related Art For example, when performing a quality inspection of a timepiece, a rate is measured by a day difference meter, and a current consumption of a stepping motor is measured by an average current meter in several step cycles. . Thus, the rate and the average current are:
The measurement was performed using different devices.

[0003]

As described above, if the rate and the average current were measured using different devices, respectively, the measurement time would be lengthened accordingly and two measuring devices would be required. Therefore, the cost was increased accordingly.

[0004] Further, depending on the timepiece, the step cycle of the stepping motor for moving the hand may be different, and in that case, the measurement cycle of the average ammeter has to be switched each time.

It is an object of the present invention to provide a period and average current measuring device capable of simultaneously and simply measuring the period and average current of an object to be measured.

[0006]

According to the present invention, a power supply voltage is supplied to an object to be measured which operates intermittently, such as a clock , via a current limiting resistor.
And a DC power supply circuit for supplying
When the power supply voltage is supplied to the DUT,
A first pulse signal generating means for generating a pulse signal corresponding to a voltage change across the current limiting resistor which changes in accordance with the operation of the above, a reference pulse generating means for generating a pulse signal of a reference frequency, A first counting means for counting reference pulses from the reference pulse generating means in response to a pulse signal from the pulse signal generating means; and an operation of the device under test based on a counting result of the first counting means. A period detecting unit for detecting a period, a second pulse signal generating unit for generating a pulse signal having a frequency corresponding to the operating current of the device under test, and a pulse signal from the first pulse signal generating unit. A second counting means for counting pulses from the second pulse signal generating means, and an average current detecting means for detecting an average current of the device under test based on the counting result of the second counting means. By providing solves the above problems.

[0007]

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a DC power supply circuit having a current limiting resistor 1a for preventing an overcurrent in order to stabilize its output voltage at, for example, 3 volts. Reference numeral 2 denotes an intermittently operated object to be measured, for example, a stepping motor drive circuit of a timepiece, which generates a drive pulse every second. The power supply terminal on the high voltage side of the DUT 2 is connected to the DC power supply circuit 1.
And a power terminal on the low voltage side is connected to a current-
It is connected to voltage conversion means 6. Reference numeral 3 denotes first pulse signal generating means for generating a pulse signal according to a voltage change between both ends of the current limiting resistor 1a due to the operation of the device under test 2, and 4 is a reference frequency for measuring an operation cycle of the device under test 2. Reference pulse generating means 5 for generating a pulse signal from the first pulse signal generating means 4 counts the reference pulse from the reference pulse generating means 4 in response to the pulse signal from the first pulse signal generating means 3, A current-voltage conversion circuit for converting a current generated by the operation of the measuring object 2 into a voltage;
Is a voltage-frequency converter that generates a pulse signal having a frequency corresponding to the output voltage of the power supply. The current-voltage conversion circuit 6 and the voltage-frequency converter 7 constitute a second pulse signal generating means. Reference numeral 8 denotes second counting means for counting the pulses from the voltage-frequency converter 7 according to the pulse signal from the first pulse signal generating means 3, and 9 denotes the first counting means 5 and the second counting means 8. Calculating means for calculating an operation cycle and an average current of the device under test 2 based on each counting result of
Numeral 0 is a keyboard for controlling the arithmetic processing of the arithmetic means 9, and 11 is a display means for displaying the arithmetic result by the arithmetic means 9.

Next, the operation of calculating the operation cycle and average current of the DUT 2 will be described with reference to the flowchart of FIG.

When the power supply terminal on the high voltage side of the DUT 2 is connected to the terminal A of the DC power supply circuit 1 and the power supply terminal on the low voltage side is connected to the terminal B of the current-voltage conversion circuit 6, the DUT 2 , And a drive pulse for the stepping motor is generated from the device under test 2 every 1 second. The voltage across the current limiting resistor 1a changes according to the operation of the device under test 2. In response to this voltage change, the first pulse signal generating means 3
As shown in FIG. 3A, a one-second pulse signal is generated.

As shown in FIG. 3B, a current corresponding to the drive current of the step motor is generated at the terminal B. The current-voltage conversion circuit 6 generates a voltage signal according to a current change at the terminal B, as shown in FIG. The voltage-frequency converter 7 generates a pulse signal having a frequency corresponding to the voltage signal from the current-voltage conversion circuit 6, as shown in FIG. The frequency of this pulse signal is a value proportional to the drive current of the step motor.

The first counting means 5 is reset and started by the rise of the pulse signal from the first pulse signal generating means 3 (step A). Thus, the first counting means 5 starts counting pulses of the reference frequency from the reference pulse generating means 4 shown in FIG.

The second counting means 8 is also reset and started at the same timing as the first counting means 5 by the rise of the pulse signal from the first pulse signal generating means 3 (step B). Thereby, the second counting means 8 starts counting pulses from the voltage-frequency converter 7.

Next, the first counting means 5 and the second counting means 8 stop counting at the next rising of the pulse signal from the first pulse signal generating means 3 (step C).

Next, the arithmetic means 9 comprises the first counting means 5
The counting time, that is, the period of the stepping motor drive pulse, is calculated based on the counting result of (i.e., the number of reference pulses counted in the counting period). Based on the number of pulses from the frequency converter 7, the average value of the current consumed by the step motor during the counting period is calculated.

In this way, the time of one cycle from the rising of the pulse signal from the first pulse signal generating means 3 to the next rising and the average current consumption of the step motor in the one cycle are calculated.

The calculating means 9 performs the above-described series of operations for a period designated by the keyboard 10, and calculates an average value of the data (step D). The calculation result is displayed on the display unit 11.

As described above, the period and the average current of the DUT 2 can be measured at one time, and the detection of the average current
Since a pulse signal generated by the first pulse generation means 3 and corresponding to the operation cycle of the device under test 2 is used, the device under test having any period can be measured. Therefore, the trouble of manually switching the measurement cycle of the average ammeter according to the operation cycle of the DUT 2 as in the related art can be eliminated, and the cycle of the DUT and the average current can be easily measured.

In the above example, a clock is used as the DUT 2, but the DUT is not limited to this, and a torsion pendulum, an electronic metronome, or the like may be used.

In the above example, the operation cycle and the current consumption are measured every cycle. However, the measurement is not limited to one cycle, but can be changed as appropriate such as two cycles or three cycles. In this case, it is necessary to appropriately set the reset timing of the first counting means 5 and the second counting means 8 in accordance therewith.

[0021]

According to the present invention, a power supply voltage is supplied to an object to be measured which operates intermittently, such as a timepiece , via a current limiting resistor.
DC power supply circuit and the DUT from the DC power supply circuit
When the power supply voltage is supplied to the
In response to a voltage change across the current limiting resistor
First pulse signal generating means for generating the same pulse signal
And reference pulse generation that generates a pulse signal of the reference frequency
Means, and a pulse signal from the first pulse signal generating means.
The reference pulse from the reference pulse generator
Counting means for counting the number of
A cycle for detecting the operation cycle of the DUT based on the numerical results.
Period detecting means, and a frequency corresponding to the operating current of the device under test
Second pulse signal generating means for generating a pulse signal of
According to the pulse signal from the first pulse signal generating means
Counting the pulses from the second pulse signal generating means.
Second counting means for performing counting, and counting results of the second counting means.
Average current for detecting the average current of the DUT based on
Since the detecting means is provided , the operating cycle of the object to be measured driven by a DC power supply that performs an intermittent operation such as a clock is measured, and at the same time, the average current is measured based on the periodic signal. Therefore, the average current in the operation cycle of the device under test can be easily and accurately measured. Therefore,
The trouble of manually switching the measurement cycle of the average ammeter according to the operation cycle of the device under test as in the related art can be eliminated, and the cycle of the device under test and the average current can be easily measured.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration example of the device of the present invention.

FIG. 2 is a flowchart for explaining the operation of the device of the present invention.

FIG. 3 is a waveform chart for explaining the operation of the device of the present invention.

[Explanation of symbols]

 Reference Signs List 3 first pulse signal generating means 4 reference signal generating means 5 first counting means 6 current-voltage conversion circuit 7 voltage-frequency converter 8 second counting means 9 calculating means

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G01R 23/10 G01R 19/00 G01R 23/02 G04D 7/00 G04D 7/12

Claims (1)

(57) [Claims] 1. A conductive intermittently operated to the object to be measured such as a watch
DC power supply circuit that supplies power supply voltage via a current limiting resistor
When, the power supply voltage supply is above the measured object from the DC power supply circuit
That changes depending on the operation of the device under test
First pulse signal generating means for generating a pulse signal according to a voltage change at both ends of the current limiting resistor; reference pulse generating means for generating a pulse signal of a reference frequency; and pulses from the first pulse signal generating means First counting means for counting a reference pulse from the reference pulse generating means in response to a signal; cycle detecting means for detecting an operation cycle of the device under test based on the counting result of the first counting means; Second pulse signal generating means for generating a pulse signal having a frequency corresponding to the operating current of the device under test; and generating the second pulse signal in response to the pulse signal from the first pulse signal generating means. Second counting means for counting the pulses from the means, and average current detecting means for detecting the average current of the device under test based on the counting result of the second counting means. And the average current measuring device.