JPS62101123A - Pulse type revolution counter - Google Patents

Abstract

PURPOSE:To prevent the measuring accuracy of the number of revolutions of a ring gear from being effected due to accuracy of the pitch of teeth supplied to the ring gear by correcting a data outputted from a pulse count means based on a stored pitch data. CONSTITUTION:A tooth formed to the ring gear 1 is detected by a pickup 2, a pulse signal is waveform-shaped by a waveform shaping circuit 3 and outputted to a clock pulse counter circuit 13. When a drive command signal is outputted from a control circuit 15 by a signal outputted to a clock pulse generating circuit 11, a pulse is outputted respectively from the clock pulse counter circuit 13. A correction circuit 14 uses a command signal from the control circuit 15 to obtain a pitch error epsiloni data read sequentially from a pitch error memory circuit 12 and a true measurement qi at each pitch. When a true measurement at each pitch is outputted from the correction circuit 14, a reciprocal of the measurement being a value inversely proportional to the number of revolutions of the ring gear 1 is displayed on a digital number of revolution display device 6.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention generally relates to a pulse type rotational speed measuring device, and more specifically, to a pulse signal that is output in accordance with the detected rotational speed of a rotating ring gear. This invention relates to a pulse-type rotational speed measuring device for counting.

[Conventional technology]

FIG. 4 is a block diagram showing an example of the configuration of a pulse type rotation speed measuring device according to the prior art. In Figure 4, 1
is the ring gear, 2 is the pickup, 3 is the waveform shaping circuit,
4 is a counter circuit, 5 is a control circuit, and 6 is a digital rotation speed display. The ring gear 1 described above is rotatably supported by a shaft (not shown), and constitutes a pulse generation mechanism. The pickup 2 detects teeth cut into the ring gear 1 and outputs a predetermined pulse signal. The waveform shaping circuit 3 receives the pulse signal output from the pickup 2, shapes the waveform of the pulse signal, and outputs the shaped waveform. The counter circuit 4 described above counts and outputs the pulse signal output from the waveform shaping circuit 3 within a prescribed time according to the control signal output from the control circuit 5. The control circuit 5 is configured to output a control signal for driving the counter circuit 4 as described above. The digital rotation speed display 6 receives count value data output from the color/return circuit 4 and displays the data digitally.

Next, the operation of the pulse type rotation speed measuring device having the above-described configuration will be explained.

When the ring gear 1 rotates and the pickup 2 detects the teeth carved into the ring gear 1, the pickup 2 outputs a pulse signal proportional to the number of detected teeth. The pulse signal is applied to a waveform shaping circuit 3, where the pulse signal is shaped, and then outputted to a counter circuit 4. On the other hand, the counter circuit 4 starts driving by outputting a control signal from the control circuit 5, and counts the number of pulse signals output from the waveform shaping circuit 3 within the time specified by the control signal. Then, the count value data proportional to the rotation speed of the ring gear 1 mentioned above is displayed on the digital rotation speed display 6.

[Problem that the invention seeks to solve]

The conventional pulse-type rotational speed measuring device is configured as described above, and has the following problems.

As mentioned above, in this pulse-type rotational speed measurement device, the rotational speed of the ring gear 1 is measured by the pickup 2.
This is done by counting the number of pulse signals output from the Now, suppose that the above-mentioned pulse-type rotational speed measuring device measures the rotational speed of the ring gear 1, which has 60 teeth approximately equally spaced. When the pickup 2 is rotating at speed m, a pulse signal of 100 pulses/second is outputted from the pickup 2 according to the formula of 00r 60gIA//4 rotations x --i J King==100 Palroy Cup. Therefore, if this pulse signal is measured for 1 second or more, it will be 1/1 including the measurement error of 1 pulse.
The measurement accuracy is 1%, and in order to improve the measurement accuracy further, the pulse signal counted by the counter circuit 4 must be increased by several tones. Therefore, in order to further improve the measurement accuracy mentioned above, for example, the control circuit 5 is provided with the function of a high-frequency clock pulse generation circuit to measure the interval between pulse signals output from the pickup 2 mentioned above. A method was devised. When measuring the rotational speed of the ring gear 1 using such a method, for example, if the oscillation frequency is 1.
■(Control circuit 5 with clock pulse generation function of 2)
If we use
For 00 seconds, lXl0 /10Q = 104 pulse signals inversely proportional to the number of rotations of the ring gear 1 are measured, and the reciprocal value of the measured data is displayed and output on the digital rotation number display 6. Therefore, if the above-mentioned measurement method is adopted, a measurement accuracy of 0.01 inch can be obtained.

However, both of the above-mentioned two types of measurement methods are valid on the assumption that there is no pitch error in the teeth carved on the ring gear 1, but in reality, the ring gear 1 is measured with no pitch error. It is extremely difficult to manufacture a pitch with no pitch error at all, and no matter how much effort is made to improve the accuracy, a pitch error of about 1 inch will inevitably occur.

Figure 2 shows ring gear 1 with such a pitch error.
An example is shown in which there is no pitch error ε] in the first pitch (that is, ε1=1.000), but the second pitch is 1% shorter than the first pitch (i.e., ε1=1.000).
g2=Q, 990), and the third pitch is also 0.5% longer than the first pitch (that is, ε3=1.005).
'). Under such an assumption, if the ring gear 1 is rotating at a constant rotation speed, 1011 (10,000) pulses are measured at the first pitch, but at the second pitch. 9 and 90 respectively on the third pitch
0 and 10,050, and it appears that the rotational speed has decreased when measuring the second pitch and has increased when measuring the third pitch. As is clear from the above, even if the number of pulses counted within a certain period of time by the temporary counter circuit 4 is increased to improve measurement accuracy, the pitch occurring in the ring gear 1 as described above Since the measurement accuracy deteriorates by the amount of error, it is practically difficult to carve the teeth into the ring gear 1 with high accuracy, so there is a problem that it is impossible to improve the measurement accuracy in the true sense.

This invention was made in order to solve the above-mentioned problems, and it is a pulse type rotation in which the measurement accuracy of the rotation speed of the ring gear is not affected by the precision of the pitch of the teeth carved into the ring gear. The purpose is to obtain a number measuring device.

[Means for solving problems]

The pulse type rotation speed measuring device according to the present invention is provided with pitch data storage means for storing pitch data for each pitch measured in advance, and performs pulse counting based on the pitch data stored in the pitch data storage means. The present invention is characterized in that a correction means is provided for correcting the data output from the means.

[For production]

The pitch data storage means in this invention stores pitch data for each pitch measured in advance, and the correction means outputs pitch data from the pulse counting means based on the pitch data stored in the pitch data storage means. O for correcting data [Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a pulse type rotational speed measuring device according to an embodiment of the present invention. Note that the symbols 1 to 3 and the symbol 6 shown in FIG. 1 are the same as those shown in FIG. 3 described above, so the explanation thereof will be omitted.

In FIG. 1, 11 is a clock pulse generation circuit, and 12 is a clock pulse generation circuit.
is a pitch data storage means, that is, a pitch error memory circuit;
13 is a clock pulse counter circuit, 14 is a correction means, that is, a correction circuit, and 15 is a control circuit.

The clock pulse generation circuit 11 described above, under the control of the control circuit 15, generates a clock pulse having a frequency of, for example, IMH2. Under the control of the control circuit 15, the clock pulse counter circuit 13 calculates the interval of pulse signals output from the waveform shaping circuit 3 within a specified time according to the clock pulse of the IMH2 transmitted from the clock pulse generation circuit 11. For example, in the first pitch, 1×106/100 per 1/100 seconds
=1o11 pulses are output, and at the second pitch, 0.990 mowing06/1/100 second is output.
100 = 9900 pulses and K 1 , 005 0 /1 for 1/100 seconds in said third pitch check
00=10050 pulses are output respectively. The pitch error memory circuit 12 stores pitch errors g, (Fi
l is a value indicating the number of teeth relative to a specific tooth of the ring gear 1. ) data from the second
The data is stored for each pitch of the ring gear 1 shown in the figure, and the data is output in accordance with a command signal output from the control circuit 5. Under the control of the control circuit 5, the correction circuit 14 described above calculates the number of pulses pl given from the clock pulse counter circuit 13 and the pitch error memory circuit 12 by 8. If you are wondering, r-
It is configured to calculate the true measured value q4'r for each pitch from the pitch error 61 data and based on the equation q, - Saraji. The control circuit 15 sends a drive command signal to the clock pulse generation circuit 11 to generate an I MHz clock pulse, and sends a drive command signal to the clock pulse counter circuit 13 to generate the clock pulse generation circuit 11.
A measurement command signal for measuring the interval of pulse signals output from the waveform shaping circuit 3 within a specified time is sent to the correction circuit 14 according to the clock pulse emitted from υ, as described above. A command signal for determining the true measurement value q1 for each pitch based on the formula is read out from the pitch error memory circuit 12 for each pitch, and ε1 data as described above is read from the circuit 12. and output command signals to be applied to the correction circuit 14. The control circuit 15 controls the drive of the entire system by adjusting the timing of outputting command signals to each of the aforementioned circuits.

Next, a pulse-type rotational speed meter with the above-mentioned configuration
The operation of f will be explained.

When the ring gear 1 rotates and the pickup 2 detects the teeth carved into the ring gear 1, the pickup 2 outputs a pulse signal proportional to the number of detected teeth. The pulse signal is applied to the waveform shaping circuit 3, where the pulse signal is shaped, and then outputted to the clock pulse counter circuit 13. On the other hand, when a clock pulse of I MHz is given from the circuit 11 by a signal output from the control circuit 15 to the clock pulse generation circuit 11 and a drive command signal is output from the control circuit 15, the clock pulse counter The circuit 13 uses the clock pulse of IMH1 given as υ,
Within the time specified by the drive command signal (for example, 1
/100 seconds), the interval between output pulses from the waveform shaping circuit 3 is measured. As mentioned above, the first pitch of the ring gear 1 shown in FIG. 2 is 1/1.
10,000 pulses in 00 seconds and 9,900 pulses in 1/'100 seconds at the second pitch.
Also, at the third pitch, 10,05 per 1/100 seconds
0 pulse counter circuit 1
It will be output from 3. These count values pi
are sequentially output to the correction circuit 14, the correction circuit 14 receives pitch errors ff sequentially read out from the pitch error memory circuit 12 in response to command signals from the control circuit 15.
From the t data and the pi f-ta, the above-mentioned qi=
Find the true measurement value (li) for each pitch using Bean's formula. In the example above, at the first pitch, pl ”
1 o, o OO* 'i = 1. Since OO, Ql = 10-000/1.00 = 10,000, and
At the second pitch p2=9,900 r 52=Q
, 990, so q2="" 0/ 0.99
0 = 10,000, and in the third pitch pler 1
0+050. Since t = 1.005, q =
``050/1.005=10.000, υ q2 at the second pitch and q5 at the third pitch both match ql at the first pitch. When the true measured values ql, q2, q5... are output from the correction circuit 14, the reciprocal value of the measured value ql+q21q5I°, which is a value inversely proportional to the rotation speed of the ring gear 1, becomes the aforementioned value. This is displayed and output on the digital rotation speed display 6.

Although the embodiment according to the present invention described above is intended to improve the accuracy of measuring the rotation speed of the ring gear 1, the technical idea of the present invention is to measure the rotation speed of a rotating body such as a ring gear. It can also be applied to improve measurement accuracy regarding linear motion or arbitrary curved motion.

〔Effect of the invention〕

As described above, according to the present invention, since the data output from the pulse counting means is corrected based on the pitch data for each pitch measured in advance, the pitch of the teeth etched in the ring gear is corrected. This has the effect of providing a pulse-type rotation speed measuring device in which the measurement accuracy of the rotation speed of the ring gear is not affected by the accuracy of the ring gear.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a pulse-type rotational speed measuring device according to an embodiment of the present invention, FIG. 2 is an explanatory diagram showing an example of pitch error of a generally used ring gear, and FIG. The figure shows a hitch 2-- according to an embodiment of the present invention.
The data diagram showing the pitch error for each pitch of the ring gear stored in the memory circuit, the measured value counted by the clock pulse counter circuit, and the true value corrected by the correction circuit, FIG. 4 is according to the prior art. FIG. 2 is a block diagram showing an example of the configuration of a pulse type rotation speed measuring device. In the figure, 1 is a ring gear, 11 is a clock pulse generation circuit, 12 is a pitch error memory circuit, 13 is a clock pulse counter circuit, and 14 is a correction circuit. In each figure, the same reference numerals indicate the same or corresponding parts. Patent applicant Mitsubishi Electric Co., Ltd. agent Patent attorney 1) Hiroshi Sawa (2 others) 114 @ Procedural amendment (voluntary)

Claims (1)

[Claims] Pulse type rotation speed measurement having a pulse counting means that counts and outputs a pulse signal output according to the detected pitch of a rotating ring gear by counting a high frequency clock pulse signal given from the outside. The apparatus is provided with a pitch data storage means for storing pitch data for each pitch measured in advance, and a correction means for correcting the data output from the pulse counting means based on the pitch data stored in the pitch data storage means. A pulse type rotation speed measuring device characterized by being provided with.