JP2003111465A - Revolution pulse detector and dc motor comprising it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a revolution pulse detector capable of detecting the revolution pulse of an armature accurately without using a large scale sensor, e.g. a rotary encoder, and a DC motor comprising the revolution pulse detector. SOLUTION: The revolution pulse detector 1 in a DC motor comprises at least a pair of brushes 82a, b and an armature 84 arranged with a commutator 83 and windings 85a, b, c. The revolution pulse detector 1 comprises means 9 for detecting revolution pulses 13 based on a current flowing between specified segments 83, b among a plurality of segments 83a, b, c formed in the commutator 83.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation pulse detecting device and a DC motor, and more particularly to a rotation pulse detecting device and a DC electric motor, which determine a rotation angle of an armature based on a current flowing between specific segments among a plurality of segments formed in a commutator. The present invention relates to a rotation pulse detecting device for detecting a rotation pulse and a DC motor using the rotation pulse detecting device.

[0002]

2. Description of the Related Art Conventionally, in a DC electric motor for adjusting an angle of a movable member such as an air mix door or a mode switching door of a vehicle air conditioner mounted on an automobile, a rotary encoder or other sensor is used to rotate an armature. The rotation pulse according to the angle is detected, and the voltage application time of the DC motor is controlled based on this rotation pulse.

However, in the above DC motor, the complicated structure due to the mounting of the sensor has been a factor that hinders downsizing and cost reduction.

Therefore, in order to detect the rotation pulse according to the rotation angle of the armature without using a large-scale sensor such as a rotary encoder, the current ripple generated in the current flowing between the brushes of the DC motor is resistor or hall element. An apparatus for measuring using a simple device is used.

Here, the current ripple is a vibration waveform containing an AC component generated in the current flowing between the brushes due to a change in the contact state between the brush and each segment of the commutator due to the rotation of the armature.

In order to detect the rotation pulse according to the rotation angle of the armature by the device for measuring the current ripple using a simple device such as a resistor or a hall element, first use the resistor or the hall element. A current ripple is detected, and this current ripple is smoothed by an integrating circuit to obtain a comparison signal.

Then, this comparison signal is compared with the above-mentioned current ripple using a comparison circuit such as a comparator, and when the oscillation waveform of the current ripple becomes higher than the threshold value by the comparison signal, a pulse signal is generated. Therefore, the rotation pulse corresponding to the rotation angle of the armature is detected.

FIG. 17 shows an operating state of the rotation pulse detecting device according to the prior art. Here, as an example, the current ripple generated in the current flowing between the brushes of the brush DC motor having the three-pole armature is shown. Also,
In the figure, the vertical axis represents voltage [V] and the horizontal axis represents time [S].

As shown in the figure, the current ripple 311 has six peak values P1 per revolution of the armature (not shown).
Through P6 appear. Then, in order to generate the desired rotation pulse 313 based on the peak values P1 to P6, each processing is performed using the integration circuit and the comparison circuit as described above.

[0010]

However, the level of the waveform of the current ripple 311 changes with the aging of the brush and the commutator (not shown), and the noise N is near the peak values P1 to P6 as shown in the figure. There were times when they overlapped each other.

Then, the rotation pulse 313a is generated by comparing the current ripple 311 with the current ripple 311 using the comparison signal 312a obtained by smoothing the current ripple 311.

However, as shown, the rotation pulse 313a
In addition to the normal signal S, the error signal E, which is an erroneous signal related to the rotation pulse detection, is also output by the noise N.

On the other hand, the comparison signal 312a is generated by using a well-known amplifier circuit composed of transistors (not shown) and the comparison signal 312b is generated, and the comparison signal 312b is compared with the current ripple 311 to generate the rotation pulse 31.
3b is generated.

However, as shown, the rotation pulse 313b
Are the peak values P1, 3, 5, 6 of the current ripple 311.
However, the normal signal S that is supposed to be obtained by the peak values P2 and P4 of the current ripple 311 is not output.

As described above, when the current ripple changes with the aging of the brush and the commutator, or noise is superimposed, an erroneous signal is output in addition to the rotation pulse, and the armature rotates. There is a problem that the detection accuracy of the rotation pulse depending on the angle is reduced.

The present invention has been made in view of the above problems, and can accurately detect the rotation pulse according to the rotation angle of the armature without using a large-scale sensor such as a rotary encoder. It is an object of the present invention to provide a detection device and a DC motor using the rotation pulse detection device.

[0017]

In order to solve the above problems, the invention according to claim 1 provides at least a pair of brushes, an armature on which a commutator and a winding are arranged, and a yoke housing which accommodates the armature. A rotation pulse detection device in a DC electric motor comprising:
The rotation pulse detection device includes pulse detection means for detecting a rotation pulse based on a current flowing between specific segments among the plurality of segments formed in the commutator.

The invention described in claim 2 is the same as claim 1.
The rotation pulse detection device according to claim 1, wherein the pulse detection means is a resistor connected in parallel with the winding between the specific segments, and a current connected in series on the cathode side of the pair of brushes. The detection means and the rotation pulse generation means connected to the current detection means.

The invention described in claim 3 is the same as that of claim 1.
The rotation pulse detection device according to claim 1, wherein the pulse detection means is an oscillator connected in parallel with the winding between the specific segments, and a current detection connected in series to the cathode side of the pair of brushes. And a rotation pulse generating means connected to the current detecting means.

The invention according to claim 4 is the same as claim 1.
The rotation pulse detection device according to claim 1, wherein the pulse detection means includes a light emitting element connected in parallel with the winding between the specific segments, a light receiving element optically coupled to the light emitting element, and the light receiving element. And a rotation pulse generating means connected to.

The invention described in claim 5 is the invention according to claim 2.
The rotation pulse detection device according to claim 1, further comprising a diode connected in series with the resistor.

The invention according to claim 6 is the same as claim 1.
It is a direct-current motor using the rotation pulse detection device according to any one of 1 to 5.

[0023]

According to the first aspect of the invention, the rotation pulse detecting device comprises pulse detecting means for detecting the rotation pulse based on the current flowing between the specific segments among the plurality of segments formed in the commutator.

Here, the commutator is configured such that the current flowing between specific segments among the plurality of segments formed in the commutator fluctuates according to the rotation angle of the armature.

Therefore, according to the invention of claim 1,
It is possible to detect a rotation pulse according to the rotation angle of the armature based on the current flowing between specific segments among the multiple segments formed in the commutator, eliminating the need for a large-scale sensor such as a rotary encoder. it can.

Further, in the invention described in claim 2, the pulse detection means is a resistor connected in parallel with the winding between the specific segments, and a current detection connected in series to the cathode side of the pair of brushes. Means and rotation pulse generating means connected to the current detecting means.

Here, the resistance value of the entire circuit of the resistance circuit constituted by the resistor and the winding changes in accordance with the rotation angle of the armature so as to cause periodic fluctuations. Therefore,
The currents flowing on the cathode side of the pair of brushes also change in a cyclic manner according to the rotation angle of the armature. The current detecting means is configured to detect the current detection signal according to the magnitude of the current flowing to the cathode side of the brush. Further, the rotation pulse generating means is configured to generate a rotation pulse from the current detection signal.

Therefore, according to the invention described in claim 2,
It is possible to detect a rotation pulse according to the rotation angle of the armature based on the current flowing between specific segments among the multiple segments formed in the commutator, eliminating the need for a large-scale sensor such as a rotary encoder. it can.

Further, in the invention described in claim 3, the pulse detecting means is an oscillator connected in parallel with the winding between specific segments, and a current detecting means connected in series to the cathode side of the pair of brushes. And a rotation pulse generation means connected to the current detection means.

Here, a current flows through the oscillator only when the armature is at a predetermined rotation angle. Further, the oscillator is configured to superimpose an AC component having a specific frequency on the current flowing between the specific segments only when the current flows. Further, the current detection means is configured to detect the current detection signal according to the magnitude of the current flowing on the cathode side of the brush. Further, the rotation pulse generating means is configured to generate a rotation pulse from the current detection signal.

Therefore, according to the invention described in claim 3,
It is possible to detect a rotation pulse according to the rotation angle of the armature based on the current flowing between specific segments among the multiple segments formed in the commutator, eliminating the need for a large-scale sensor such as a rotary encoder. it can.

Further, in the invention described in claim 4, the pulse detecting means is connected to the light emitting element connected in parallel with the winding between the specific segments, the light receiving element optically coupled to the light emitting element, and the light receiving element. Rotation pulse generating means.

Here, a current flows through the light emitting element only when the armature is at a predetermined rotation angle. Further, the light emitting element is configured to output a light emission signal in a specific frequency band only when a current flows. The light receiving element is configured to output a light receiving signal by inputting a light emitting signal. Further, the rotation pulse generating means,
It is configured to generate a rotation pulse from the received light signal.

Therefore, according to the invention of claim 4,
It is possible to detect a rotation pulse according to the rotation angle of the armature based on the current flowing between specific segments among the multiple segments formed in the commutator, eliminating the need for a large-scale sensor such as a rotary encoder. it can.

When a diode connected in series with a resistor is provided as in the invention described in claim 5,
It is possible to halve the power consumed by the resistor per one rotation of the armature.

Further, according to the invention of claim 6, since the rotation pulse detecting device of any of claims 1 to 5 is used, a large-scale sensor such as a rotary encoder is not used. Further, it is possible to accurately detect the rotation pulse according to the rotation angle of the armature, and further it is possible to adjust the driven mechanism (not shown) connected to the DC motor to a desired angle.

[0037]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. The members, arrangements, etc. described below do not limit the present invention, and it goes without saying that various modifications can be made in accordance with the spirit of the present invention.

1 to 13 show one embodiment of the present invention, and FIG. 1 is a block diagram showing the configuration of a rotation pulse detecting device according to the first embodiment of the present invention. Figure 2
FIG. 6 is a block diagram showing a configuration of a rotation pulse detection device according to a second embodiment of the present invention. FIG. 3 is a block diagram showing the configuration of the rotation pulse detection device according to the third embodiment of the present invention.

FIG. 4 is a circuit diagram showing a low pass filter according to an embodiment of the present invention. FIG. 5 is a circuit diagram showing an integrating circuit according to an embodiment of the present invention.

FIG. 6 is a diagram showing a partial configuration of the DC motor according to the first embodiment of the present invention. 7 and 8 show
It is a figure which shows the rotation state of the direct-current motor which concerns on 1st embodiment of this invention.

9 and 10 are views showing a rotation pulse generation process by the rotation pulse detection device of the first embodiment of the present invention. FIG. 11: is a figure which shows the rotation pulse generation process by the rotation pulse detection apparatus of 2nd embodiment of this invention. FIG. 12 is a diagram showing a rotation pulse generation process by the rotation pulse detection device of the third embodiment of the present invention.

FIG. 13 is a block diagram showing the structure of the DC motor according to the first embodiment of the present invention.

For easy understanding, FIGS. 7 and 8 show the configuration of only the motor section 81 shown in FIG.
Further, as shown in (1) to (12), the armature 84 is in an operating state in which it is rotating in the R direction.

The rotation pulse detecting device and the DC motor according to the embodiment of the present invention will be described below with reference to FIGS. 1 to 13.

(First Embodiment) First, although the rotation pulse detecting device 1 according to the first embodiment of the present invention shown in FIG. 1 is not shown, for example, a vehicle air conditioner mounted on an automobile. It is used for a DC motor for adjusting the angle of movable members such as the air mix door and the mode switching door.

In the above DC motor, the rotation pulse detecting device 1 according to the first embodiment of the present invention is disposed integrally with the motor section 81 of this DC motor, and the armature 84, which is a component of the motor section 81, is provided. The rotation pulse 13 corresponding to the rotation angle is detected.

The configuration of the rotation pulse detection device 1 according to the first embodiment of the present invention shown in FIG. 1 will be described below.

The rotation pulse detecting device 1 according to the first embodiment of the present invention includes a pulse detecting device 9 as a pulse detecting means.
Is equipped with. This pulse detection device 9 includes a resistor 2 and
It is composed of a current detector 3 as current detection means and a rotation pulse generation circuit 4 as rotation pulse generation means.

The rotation pulse generation circuit 4 is composed of an amplification circuit 41, a comparison signal generation circuit 42, and a comparison circuit 43.

The resistor 2 includes a plurality of windings 85a, b, between the specific segments 83a, b among the plurality of segments 83a, b, c formed in the commutator 83.
It is connected in parallel with a predetermined winding 85a of c.

One end of the current detector 3 is connected to the brush 82b on the cathode side, and both ends thereof are connected to the input terminal of the amplifier circuit 41. The output of the amplifier circuit 41 is the input terminal of the comparison signal generation circuit 42 and the comparison circuit 4.
3 are respectively connected to the positive side input terminals. The output of the comparison signal generation circuit 42 is connected to the negative input terminal of the comparison circuit 43.

As the resistor 2 and the current detector 3, a metal oxide film fixed resistor having a terminal, a carbon film fixed resistor or the like is used. A chip resistor may be used for downsizing. Further, a variable resistor may be used to change the resistance value and obtain a desired voltage waveform. In addition, the resistance value of these resistors is the winding 85a,
It is set within the limit of the rated current of b, c or the brushes 82a, b.

The amplifier circuit 41 is for amplifying an input signal with a constant amplification factor and outputting it, and a general operational amplifier is used. Further, a resistor (not shown) or the like is connected to the operational amplifier according to the amplification factor.

Further, the comparison signal generation circuit 42 is for smoothing the input signal, and as shown in FIG.
2a, operational amplifier 42b, low-pass filter 47 to which capacitor 42c is connected, or integrator circuit 4 to which resistor 42a and capacitor 42c are connected as shown in FIG.
It is composed of 8.

It should be noted that the output of the low-pass filter 47 or the integrating circuit 48 used as the comparison signal generating circuit 42 may be connected to an amplifier circuit composed of transistors (not shown) for amplifying the output signal.

The comparison circuit 43 is for comparing two input signals and outputting a binary signal concerning the magnitude thereof, and is constituted by a general comparator or the like.

The comparator has two input terminals on the plus side and the minus side, and if the signal input to the plus side input terminal is larger than the signal input to the minus side input terminal, It is configured so that a predetermined voltage signal can be output from the output terminal. On the other hand, if the signal input to the positive input terminal is smaller than the signal input to the negative input terminal,
The voltage signal is not output from the output terminal.

Note that, as shown in FIG.
The diode 31 may be connected in series. As the diode 31 in this case, a rectifier diode that can pass a current only in the forward direction is used.

The configuration of the rotation pulse detecting device 1 according to the first embodiment of the present invention is as described above. Next, the operation of the rotation pulse detection device 1 according to the first embodiment of the present invention will be described.

The rotation pulse detector 1 according to the first embodiment of the present invention detects the rotation pulse 13 according to the rotation angle of the armature 84.

In order to detect the rotation pulse 13, first, a drive voltage is applied between the brushes 82a and 82b from an external power source (not shown).

When a drive voltage is applied between the brushes 82a and 82b, the armature 84 rotates. Armature 84 at this time
The current flowing from the external power supply (not shown) to the brush 82a during the rotation of the
It flows through any of 5a, b, and c to the brush 82b side.

Here, when the armature 84 rotates, the path of the current flowing between the brushes 82a and 82b differs depending on the rotation angle of the armature 84 shown in FIGS.

That is, in the state (1) shown in FIG.
The current flowing from the external power supply (not shown) to the brush 82a flows in parallel with the winding 85a and the resistor 2 and flows to the brush 82a.
b flow path and winding 85c after flowing through winding 85b
To the brush 82b.

Then, from the state of (1), the armature 84
Is rotated in the direction R to the state shown in (2), the current flowing from the external power supply (not shown) to the brush 82a flows through the winding 85a and the resistor 2 in parallel with each other. 85b to branch to the flow path of brush 82b
Flow to. Here, no current flows through the winding 85b because both ends of the winding 85b are short-circuited by the brush 82a to have an equal potential.

Then, from the state of (2), the armature 84
In the state in which the brush rotates in the direction R and becomes as shown in (3), the current flowing from the external power supply (not shown) to the brush 82a flows through the winding 85b and then the winding 85a and the resistor 2a.
To a brush 82b.

Then, from the state of (3), the armature 84
In a state in which the brush rotates in the direction R and becomes as shown in (4), the current flowing from the not-shown external power source to the brush 82a is branched into a path flowing through the winding 85b and a path flowing through the winding 85c. And flows to the brush 82b. Here, no current flows through the winding 85a and the resistor 2 because both ends thereof are short-circuited by the brush 82b to have an equal potential.

Then, from the state of (4), the armature 84
In the state shown in (5) by rotating in the direction R, the current flowing from the external power source (not shown) to the brush 82a flows through the winding 85b and the winding after flowing through the winding 85c. 85a and the path | route which flows through the resistor 2 in parallel are branched, and it flows into the brush 82b.

Then, from the state of (5), the armature 84
Is rotated in the direction R to the state shown in (6), the current flowing from the external power source (not shown) to the brush 82a is parallel to the path through the winding 85b and the winding 85a and the resistor 2. And flow to the brush 82b. Here, no current flows through the winding 85c because both ends of the winding 85c are short-circuited by the brush 82a to have an equal potential.

Then, from the state of (6), the armature 84
Is rotated in the direction R as shown in (7), the current flowing from the external power supply (not shown) to the brush 82a flows through the winding 85c and then the winding 85b, and 85a and the path | route which flows through the resistor 2 in parallel are branched, and it flows into the brush 82b.

Then, from the state of (7), the armature 84
Is rotated in the direction R as shown in (8), the current flowing from the external power source (not shown) to the brush 82a causes the current flowing through the winding 85c and the winding 85a and the resistor 2 to be parallel to each other. And flow to the brush 82b. Here, no current flows through the winding wire 85b because both ends thereof are short-circuited by the brush 82b to have an equal potential.

Then, from the state of (8), the armature 84
In a state in which the brush rotates in the direction R as shown in (9), the current flowing from the not-shown external power source to the brush 82a is parallel to the path flowing through the winding 85c and the winding 85a and the resistor 2. And then flows to the brush 82b.

Then, from the state of (9), the armature 84
In the state in which the brush rotates in the direction R and becomes as shown in (10), the current flowing from the not-shown external power source to the brush 82a is branched into a path flowing through the winding 85c and a path flowing through the winding 85b. And flows to the brush 82b. It should be noted that no current flows through the winding 85a and the resistor 2 because both ends thereof are short-circuited by the brush 82a to have an equal potential.

Then, from the state of (10), the armature 8
In the state in which 4 rotates in the direction R and becomes as shown in (11), the current flowing from the external power source (not shown) into the brush 82a flows through the winding 85a and the resistor 2 in parallel and then the winding A path flowing through the brush 85b is branched into a path flowing through the winding 85b and a path flowing through the winding 85b.

Then, from the state of (11), the armature 8
In the state in which 4 rotates in the direction R and becomes as shown in (12), the current flowing from the external power source (not shown) to the brush 82a is wound in the winding 85a and the resistor 2 in parallel. The brush 82b is diverged into a path flowing through the line 85b.
Flow to. Here, no current flows through the winding 85c because both ends of the winding 85c are short-circuited by the brush 82b to have an equal potential.

As described above, the path of the current flowing between the brushes 82a and 82b differs depending on the rotation angle of the armature 84. In the states (1) to (12), the windings 85a,
The resistance value of the resistance circuit combined with b and c and the resistor 2 changes.

That is, the resistor 2 shown in FIG.
By being connected in parallel with 5a, it plays a role of periodically varying the resistance value between the segments 83a, 83b. Therefore,
The current flowing from the brush 82b changes periodically.

Then, the current detector 3 detects the voltage between the terminals corresponding to the magnitude of the current flowing from the brush 82b with periodic fluctuations as the current detection signal 10 and the amplifier circuit 41.
Output to.

The amplifier circuit 41 receives the current detection signal 10 and does not change the fluctuation cycle of the current detection signal 10
Only the amplitude is amplified by a predetermined amplification factor, and the amplified signal 11 having an oscillating waveform is output to the comparison signal generation circuit 42 and the comparison circuit 43.

The comparison signal generation circuit 42 receives the amplified signal 11, smoothes it, and outputs it as the comparison signal 12 to the comparison circuit 43.

The comparator circuit 43 inputs the amplified signal 11 at the plus side input terminal and the comparison signal 12 at the minus side input terminal. Then, the comparison circuit 43 compares the input amplified signal 11 and the comparison signal 12 in real time,
When the amplified signal 11 is smaller than the comparison signal 12, low (L) is output, and when the amplified signal 11 is larger than the comparison signal 12, high (H) which is a predetermined voltage is output.

As described above, the output terminal of the comparison circuit 43 outputs low (L) or high (H) depending on the magnitude of the amplification circuit 41 and the comparison signal 12, which is used as a pulse signal for the rotation pulse. 13 is output.

FIG. 9 shows a process of generating the rotation pulse 13 for one cycle of the armature 84 using the amplified signal 11 and the comparison signal 12.

In the figure, the vertical axis represents voltage [V] and the horizontal axis represents time [s]. Further, the peak values P1 to 12 are
The voltage value at each rotation angle during one rotation of the armature 84 shown in (1) to (12) of FIGS. 7 and 8 is shown.

As shown in FIG. 9, the above-mentioned amplified signal 11 has a waveform with periodic vibration. On the other hand, the above-mentioned comparison signal 12 has a linear waveform showing substantially the same voltage value over time.

When the voltage value of the amplified signal 11 is smaller than the voltage value of the comparison signal 12, the rotation pulse 13 is low (L). On the other hand, when the voltage value of the amplified signal 11 is larger than the voltage value of the comparison signal 12,
The rotation pulse 13 is high (H). Further, the rotation pulse 13 has two pulses per cycle.

While the armature 84 shown in FIG. 1 is continuously rotated, the rotation pulse 13 for one cycle shown in FIG. 9 can be continuously detected for each rotation of the armature 84.

In the present embodiment shown in FIG. 1, for convenience, the windings 85a, b, c are shown to have three poles, but the number of windings 85a, b, c is seven poles. Alternatively, the number of poles may be increased to nine.

In this way, the number of windings 85a, 85b, 85c is increased, and the segments 83a, 83a of the commutator 83 are
By configuring the numbers of b and c to be the same as that of the windings 85a, b and c, the pulse number of the rotation pulse 13 during one rotation of the armature 84 can be increased.

Further, by increasing the number of pulses of the rotation pulse 13, the rotation angle of the armature 84 detected per pulse can be made small, so that the armature 8
The detection accuracy of the rotation angle of No. 4 can be improved.

Further, in the rotation pulse detecting device 1, a flip-flop (not shown) or the like is connected to the output terminal of the comparison circuit 43, and as shown in FIG. 9, the reference clock 1 (not shown) is synchronized with the rising edge of the rotation pulse 13. It may be configured to output the rotation pulse 13a that is a pulse output.

As described above, when the rotation pulse 13a, which is one pulse of the reference clock, is output, the processing in the arithmetic processing unit (not shown) connected to the subsequent stage of the rotation pulse detecting device 1 is performed. Is preferable because it is simple.

Further, as shown in FIG. 6, when the diode 31 is connected in series to the resistor 2, the armature 84 is
It is possible to halve the power consumed by the resistor per one rotation of the.

Here, for the motor section 81 shown in FIG. 6, the armature 8 using the amplified signal 11 and the comparison signal 12 is used.
10 shows the process of generating the rotation pulse 13 for one cycle of 4
Shown in. Further, the vertical axis of the figure shows the voltage [V] and the horizontal axis shows the time [s].

As for the peak values P1 to P12, the armature 84 shown in FIG.
The voltage values are shown for each rotation angle shown in (12).

Although the waveform is different from that of the amplified signal 11 shown in FIG. 9, the amplified signal 11 shown in FIG. 10 also has a waveform accompanied by periodic vibration. Further, the comparison signal 12 also has a linear waveform that shows substantially the same voltage value over time. Moreover, the number of pulses per cycle of the rotation pulse 13 is one.

That is, as shown in FIG. 6, by connecting the diode 31 to the resistor 2 in series, the diode 3 is changed depending on the rotation angle of the rotating armature 84.
When 1 goes in the forward direction, current flows through the resistor 2, and when the diode 31 goes in the reverse direction, the current flowing through the resistor 2 is limited to one direction so that the current does not flow through the resistor 2.

Therefore, the power consumed by the resistor 2 per one rotation of the armature 84 can be halved.

The configuration of the rotation pulse detection device 1 according to the first embodiment of the present invention is as described above. Next, the configuration of the DC motor 91 using the rotation pulse detection device 1 according to the first embodiment of the present invention shown in FIG. 13 will be described.

Although not shown, the DC motor 91 according to the present embodiment is for adjusting the angle of a movable member such as an air mix door or a mode switching door of a vehicle air conditioner such as an automobile. Is.

For this DC motor 91, the rotation pulse detecting device 1 according to the first embodiment of the present invention shown in FIG. 1 is used, and further, the motor section 81, the drive voltage generating device 6, the control device 7, and the arithmetic device. 8 are provided.

The motor portion 81 includes a yoke housing 86.
Is used. A pair of magnets 87 is arranged inside the yoke housing 86. An armature 84 is housed inside the pair of magnets 87.

The armature 84 is provided with a rotary shaft 90. The rotating shaft 90 has a commutator 83,
A core 88 is arranged. Also, windings 85a, b, and c are wound around the core 88.

The rotary shaft 90 is connected to the yoke housing 8
The bearings 89 are rotatably supported by a pair of bearings 89 disposed in the bearing 6. The armature 84 is the yoke housing 8
It is arranged so as to be rotatable within 6.

In the yoke housing 86, a pair of brushes 82a and 82b are disposed so as to be in sliding contact with the commutator 83 by a brush holder (not shown). Further, the brushes 82a, 82b are configured to be able to energize the windings 85a, 85b, 85c via the commutator 83.

For the drive voltage generator 6, a general regulator (not shown) is used. This regulator
While inputting a constant control signal, a constant voltage can be output. The output voltage at this time is predetermined by the rated voltage of the motor unit 81. The output terminal of the drive voltage generator 6 is
It is connected to the pair of brushes 82a and 82b, respectively.

The control unit 7 has a general MP (not shown).
U is used. A program capable of outputting a desired signal according to an input signal is written in the MPU. And by this program,
The above-mentioned MPU is configured so as to be able to output a pulse having a constant cycle according to an operation signal from a user (not shown). The control device 7 is connected to the arithmetic device 8.

As the arithmetic unit 8, although not shown, a counter having two input terminals for inputting a pulse is used. This counter is configured to count and store the pulses input from one of the input terminals.

When an output command signal is input from an external operating device (not shown), the counter reaches the count value of the pulses input from the other of the input terminals until it reaches the count value of the pulse input from one of the input terminals. , Is capable of outputting a constant signal. The arithmetic unit 8 is connected to the drive voltage generator 6.

The configuration of the rotation pulse detecting device 1 used in the DC motor 91 is as described above. The rotation pulse detection device 1 is connected to the arithmetic device 8.

The rotation pulse detector 1, the drive voltage generator 6, the controller 7, and the arithmetic unit 8 are collectively mounted on a small printed circuit board or the like (not shown) and arranged inside the yoke housing 86. Is desirable.

The configuration of the DC motor 91 using the rotation pulse detecting device 1 according to the first embodiment of the present invention is as described above. Next, the operation of the DC motor 91 using the rotation pulse detection device 1 according to the first embodiment of the present invention shown in FIG. 13 will be described.

The DC motor 91 using the rotation pulse detecting device 1 according to the first embodiment of the present invention detects the rotation pulse 13 according to the rotation angle of the rotating armature 84 and sets the armature 84 at a desired angle. It is something that rotates.

Then, the DC motor 91 according to the present embodiment.
In order to rotate the armature 84 to a desired angle, an operation signal (neither is shown) is output to the control device 7 by an external operation device.

The external operation device at this time is, for example, a central control device provided in a vehicle such as an automobile.
Therefore, a driver (not shown) operates the operation switch of the indoor air conditioner at the driver's seat,
An operation signal is output to the control device 7.

Then, the control device 7 receives the above-mentioned operation signal, generates a rotation angle command pulse 14 consisting of a pulse having a constant cycle according to the operation signal, and outputs it to the arithmetic device 8.

Then, the arithmetic unit 8 inputs the rotation angle command pulse 14 from one input terminal (not shown), counts and stores the number of pulses of the rotation angle command pulse 14.

Further, the arithmetic unit 8 receives a control signal 15 when an output command signal (not shown) is input from the above-mentioned external operating device.
Is output to the drive voltage generator 6.

The drive voltage generator 6 receives the control signal 15 and applies the drive voltage 16 for rotating the armature 84 between the brushes 82a and 82b.

When a drive voltage is applied between the brushes 82a and 82b, it is rectified by the commutator 83 and the winding 85a and
A current flows through b and c sequentially. The windings 85a, b,
The armature 84 is rotated by the field between c and the magnet 87.

When the armature 84 rotates, the rotation pulse detector 13 outputs the rotation pulse 13 to the arithmetic unit 8.

The arithmetic unit 8 inputs the rotation pulse 13 and, while counting the pulse number of the input rotation pulse 13, compares it with the count value of the pulse number of the rotation angle command pulse 14 described above. While the count value of the number of pulses of the rotation pulse 13 is smaller than the count value of the number of pulses of the rotation angle command pulse 14, the arithmetic unit 8 continues to output the control signal 15 to the drive voltage generator 6.

When the count value of the number of rotation pulses 13 reaches the count value of the number of rotation angle command pulses 14, the arithmetic unit 8 stops outputting the control signal 15. At this time, all the count values stored in the arithmetic unit 8 are cleared, and the input of the rotation angle command pulse 14 output next time is awaited.

DC motor 9 according to the first embodiment of the present invention
The operation of 1 is as described above. In this way, the DC motor 91 can detect the rotation pulse 13 according to the rotation angle of the armature 84 by using the rotation pulse detection device 1 and rotate the armature 84 to a desired angle.

(Second Embodiment) The operation of the DC motor 91 using the rotation pulse detecting device 1 according to the first embodiment of the present invention is as described above. Next, the configuration of the rotation pulse detection device 101 according to the second embodiment of the present invention shown in FIG. 2 will be described.

The rotation pulse detecting device 101 according to the second embodiment of the present invention shown in FIG. 2 is similar to the rotation pulse detecting device 1 shown in FIG. It is used in a DC motor for adjusting the angle of a movable member such as a mode switching door.

In the above DC motor, the rotation pulse detecting device 101 according to the second embodiment of the present invention is disposed integrally with the motor section 81 of this DC motor, and the motor section 81
The rotation pulse 113 corresponding to the rotation angle of the armature 84, which is a component of the above, is detected.

The rotation pulse detecting device 101 according to the second embodiment of the present invention includes a pulse detecting device 109 as a pulse detecting means. This pulse detector 1
09 is composed of an oscillator 102, a current detector 3, and a rotation pulse generation circuit 104 as a rotation pulse generation means.

The rotation pulse generating circuit 104 includes an amplifier circuit 41, a filtering circuit 144, and an integrating circuit 14.
5 and a waveform shaping circuit 146.

Then, the oscillator 102 includes the commutator 8
Between the specific segments 83a, b among the plurality of segments 83a, b, c formed in
Of b and c, it is connected in parallel with a predetermined winding 85a.

The oscillator 102 is composed of an electric circuit to which a crystal oscillator or the like (not shown) is connected, and is configured to be able to output an AC signal having a specific frequency when a power supply voltage is applied. Has been done.

It is necessary that the frequency of the oscillator 102 is not synchronized with the rotation speed of the armature 84, and it is desirable to use a frequency of about 100 KHz, for example. Further, it is preferable to use a clock IC or the like composed of CMOS for the oscillator 102 because the device is simplified.

One end of the current detector 3 is the brush 82b.
Of the amplifier circuit 41, and both ends thereof are connected to the input terminal of the amplifier circuit 41. The output terminal of the amplifier circuit 41 is connected to the input terminal of the filtering circuit 144, and the output terminal of the filtering circuit 144 is connected to the input terminal of the integrating circuit 145. Further, the output terminal of the integrating circuit 145 is connected to the input terminal of the waveform shaping circuit 146.

The current detector 3 and the amplifier circuit 41 are the same as those used in the rotary pulse detector 1 shown in FIG. 1 and are designated by the same reference numerals. Therefore, regarding the configurations of the current detector 3 and the amplifier circuit 41, the above description will be referred to. However, the amplifier circuit 41 is
It is necessary to use the one having a frequency characteristic capable of processing the AC signal emitted from the two.

The filtering circuit 144 is composed of a well-known electric circuit capable of extracting only a specific AC component from the input signal and outputting the AC signal.

The integrating circuit 145 is an electric circuit that integrates the input AC signal and outputs a smoothed signal.
It is composed of an integrating circuit in which a capacitor and a resistor are connected.

The waveform shaping circuit 146 is an electric circuit for binarizing an analog signal with a specific threshold value, and is composed of, for example, a digital circuit using a flip-flop (not shown) or the like.

The configuration of the rotation pulse detecting device 101 according to the second embodiment of the present invention is as described above. Next, the operation of the rotation pulse detection device 101 according to the second embodiment of the present invention will be described.

The rotation pulse detecting device 101 according to the second embodiment of the present invention is for detecting the rotation pulse 113 according to the rotation angle of the armature 84.

In order to detect the rotation pulse 113, first, a driving voltage is applied between the brushes 82a and 82b from an external power source (not shown) to rotate the armature 84.

Here, when the armature 84 rotates, the path of the current flowing between the brushes 82a and 82b becomes as described above.
It depends on the rotation angle of the armature 84.

Therefore, the current flows from the brush 82a to the winding 8
Oscillator 10 only if it flows to brush 82b through 5a.
No. 2 is energized. Then, when the oscillator 102 is energized, it outputs an AC signal having a specific frequency.

The AC component of this AC signal is superimposed on the current flowing between the brushes 82a and 82b.

The current detector 3 detects a terminal voltage corresponding to the magnitude of the current flowing between the brushes 82a and 82b as a current detection signal 110 and outputs it to the amplifier circuit 41.

The amplifier circuit 41 inputs the current detection signal 110, amplifies only the amplitude of the current detection signal 110 at a predetermined amplification rate without changing the fluctuation cycle of the current detection signal 110, and outputs the amplified signal 111 to the filtering circuit 144. Output.

The filtering circuit 144 outputs the amplified signal 1
Enter 11. Then, only the AC component of the amplified signal 111 is extracted to generate the AC signal 118, and the integrating circuit 1
Output to 45.

The integrating circuit 145 inputs the AC signal 118, smoothes it, and outputs the smoothed signal 119 as a waveform shaping circuit 1.
Output to 46.

The waveform shaping circuit 146 uses the smoothed signal 119.
Enter. Then, the smoothed signal 119 is converted into a digital value. Then, the rotation pulse 13 is output by using this as a pulsed signal.

FIG. 11 shows a process of generating the rotation pulse 113 for one cycle of the armature 84 using the amplified signal 111. The vertical axis of the figure represents voltage [V] and the horizontal axis represents time [s].

As shown in FIG. 11, the amplified signal 111 is
It has a waveform with periodic vibrations. Further, the AC component 120 is superimposed on the amplified signal 111 by the AC signal emitted from the oscillator 102.

Then, the AC signal 118 is generated by extracting the AC component 120 from the amplified signal 111. A smoothed signal 119 is generated by smoothing this AC signal 118.

Then, the rotation pulse 113 is generated by converting the smoothed signal 119 into a digital value.

It should be noted that while the armature 84 shown in FIG. 2 is continuously rotated, the armature 84 shown in FIG.
The rotation pulse 113 for one cycle shown in can be continuously detected.

In the present embodiment shown in FIG. 2, the windings 85a, b, c are shown to have three poles for the sake of convenience, but the number of windings 85a, b, c is seven poles. Alternatively, the number of poles may be increased to nine. Also, a plurality of oscillators 102 can be connected. However, the oscillator 102 needs to be smaller than the number of the windings 85a, 85b, 85c provided.

As described above, by increasing the number of windings 85a, 85b, and 85c and connecting a plurality of oscillators 102, the number of rotation pulses 113 during one rotation of the armature 84 can be increased.

Further, by increasing the number of rotation pulses 113, the armature 84 detected per pulse is detected.
Since the rotation angle of the armature 84 can be reduced, the detection accuracy of the rotation angle of the armature 84 can be improved.

Further, in the rotation pulse detecting device 101, a flip-flop (not shown) or the like is connected to the output terminal of the waveform shaping circuit 146, and as shown in FIG.
1 of the reference clock not shown in synchronization with the rising edge of 3
It may be configured to output the rotation pulse 113a that is a pulse output.

As described above, when the rotation pulse 113a, which is one pulse of the reference clock, is output, the processing in the arithmetic processing unit (not shown) connected to the subsequent stage of the rotation pulse detection device 1 is performed. Is preferable because it is simple.

The operation of the rotation pulse detecting device 101 according to the second embodiment of the present invention is as described above. Next, FIG.
A DC motor 191 using the rotation pulse detection device 101 according to the second embodiment of the present invention shown in will be described.

Although not shown, the DC motor 191 according to the present embodiment is for adjusting the angle of movable members such as an air mix door and a mode switching door of a vehicle air conditioner such as an automobile. Is.

The DC motor 191 using the rotation pulse detecting device 101 according to the second embodiment of the present invention is the same as the DC motor 91 using the rotation pulse detecting device 1 according to the first embodiment of the present invention described above. It is composed.

That is, the DC motor 1 according to this embodiment.
91 is configured by using the rotation pulse detection device 101 according to the second embodiment of the present invention shown in FIG. 2 instead of the rotation pulse detection device 1 according to the first embodiment of the present invention shown in FIG.

Further, the DC motor 191 according to this embodiment.
The drive voltage generating device 6, the control device 7, and the arithmetic device 8 which are the components of the above are the same as those used for the DC motor 91 using the rotation pulse detecting device 1 according to the first embodiment of the present invention. Therefore, the description of the drive voltage generator 6, the controller 7, and the arithmetic unit 8 is omitted here.

With the above structure, the DC motor 191 according to this embodiment can detect the rotation pulse 113 corresponding to the rotation angle of the rotating armature 84 and rotate the armature 84 to a desired angle. .

(Third Embodiment) A DC motor 19 using a rotation pulse detecting device 101 according to a second embodiment of the present invention.
The description of 1 is as described above. Next, the configuration of the rotation pulse detection device 201 according to the third embodiment of the present invention shown in FIG. 3 will be described.

The rotation pulse detecting device 201 according to the third embodiment of the present invention shown in FIG. 3 is similar to the rotation pulse detecting device 1 shown in FIG. It is used in a DC motor for adjusting the angle of a movable member such as a mode switching door.

In the above DC motor, the rotation pulse detecting device 201 according to the third embodiment of the present invention is disposed integrally with the motor section 81 of this DC motor, and the motor section 81
The rotation pulse 213 corresponding to the rotation angle of the armature 84, which is a component of the above, is detected.

The rotation pulse detecting device 201 according to the third embodiment of the present invention includes a pulse detecting device 209 as a pulse detecting means. This pulse detector 2
A light emitting element 202, a light receiving element 203, and a rotation pulse generation circuit 204 as a rotation pulse generation means.

The light emitting element 202 is composed of a light emitting diode or the like, and is configured to be capable of emitting infrared rays having a specific wavelength only when a current flows in the forward direction.

The light emitting element 202 has a plurality of windings 85 between specific segments 83a, b among the plurality of segments 83a, b, c formed in the commutator 83.
It is connected in parallel with a predetermined winding 85a among a, b, and c.

The light receiving element 203 is composed of a phototransistor or the like, and is configured to be able to output a constant voltage when the light receiving section receives infrared rays having a specific wavelength. Then, the light receiving element 203
Are arranged so that they can be optically coupled to the light emitting element 202.

The rotation pulse generation circuit 204 includes the light receiving element 2
It is composed of an amplifier, a buffer, etc. for amplifying the voltage output from the circuit 03, and is configured to be able to output a digital signal.

It is preferable to use the one package in which the light receiving element 203 and the rotation pulse generating circuit 204 are composed of CMOS because the device is simplified.

The configuration of the rotation pulse detecting device 201 according to the third embodiment of the present invention is as described above. Next, the operation of the rotation pulse detection device 201 according to the third embodiment of the present invention will be described.

The rotation pulse detector 201 according to the third embodiment of the present invention is for detecting the rotation pulse 213 according to the rotation angle of the armature 84.

In order to detect the rotation pulse 213, first, a driving voltage is applied between the brushes 82a and 82b from an external power source (not shown) to rotate the armature 84.

Here, when the armature 84 rotates, the path of the current flowing between the brushes 82a and 82b is as described above.
It depends on the rotation angle of the armature 84.

Therefore, the current flows from the brush 82a to the winding 8
Light emitting element 2 only when it flows to brush 82b through 5a
02 is in a state of being energized in the forward direction. When the light emitting element 202 is energized in the forward direction, the light emitting signal 210 having a specific wavelength is emitted.

The light receiving element 203 is the light emitting element 20.
2 receives the light emission signal 210 output according to the presence or absence of energization, detects the light reception signal 211, and outputs the rotation pulse generation circuit 2
Output to 04.

Then, the rotation pulse generation circuit 204 receives the light reception signal 211 output from the light receiving element 203, converts it into a digital signal, and outputs a rotation pulse 213.

FIG. 12 shows a process of generating the rotation pulse 213 for one cycle of the armature 84 by using the received light signal 211. The vertical axis of the figure represents voltage [V] and the horizontal axis represents time [s].

As shown in FIG. 12, when the light reception signal 211 has a pulse, the rotation pulse 213 also has a pulse.

It should be noted that while the armature 84 shown in FIG. 3 is continuously rotated, the armature 84 shown in FIG.
The rotation pulse 213 for one cycle shown in can be continuously detected.

In the present embodiment shown in FIG. 3, for convenience, the windings 85a, b, c are shown to have three poles, but the number of windings 85a, b, c is 7 poles. Alternatively, the number of poles may be increased to nine. Further, a plurality of light emitting elements 202 can also be connected.

As described above, by increasing the number of windings 85a, 85b, 85c and connecting a plurality of light emitting elements 202, the number of rotation pulses 213 during one rotation of the armature 84 can be increased.

Further, by increasing the number of rotation pulses 213, the armature 84 detected per pulse is detected.
Since the rotation angle of the armature 84 can be reduced, the detection accuracy of the rotation angle of the armature 84 can be improved.

Further, in the rotation pulse detecting device 201, a flip-flop (not shown) is connected to the output terminal of the rotation pulse generation circuit 204, and as shown in FIG. 12, a reference clock (not shown) is synchronized with the rising edge of the rotation pulse 113. It is also possible to output the rotation pulse 213a which is the output of one pulse.

As described above, when the rotation pulse 213a, which is one pulse of the reference clock, is output, the processing in the arithmetic processing unit or the like (not shown) connected to the subsequent stage of the rotation pulse detecting device 1 is performed. Is preferable because it is simple.

The operation of the rotation pulse detecting device 201 according to the third embodiment of the present invention is as described above. Next, FIG.
A DC motor 291 using the rotation pulse detection device 201 according to the third embodiment of the present invention shown in will be described.

Although not shown, the DC motor 291 according to this embodiment is for adjusting the angle of movable members such as an air mix door and a mode switching door of an air conditioner for a vehicle such as an automobile. Is.

The DC motor 291 using the rotation pulse detecting device 201 according to the third embodiment of the present invention is the same as the DC motor 91 using the rotation pulse detecting device 1 according to the first embodiment of the present invention described above. It is composed.

That is, the DC motor 2 according to this embodiment.
91 is configured by using the rotation pulse detection device 201 according to the third embodiment of the present invention shown in FIG. 3 instead of the rotation pulse detection device 1 according to the first embodiment of the present invention shown in FIG.

Further, the DC motor 291 according to this embodiment.
The drive voltage generating device 6, the control device 7, and the arithmetic device 8 which are the components of the above are the same as those used for the DC motor 91 using the rotation pulse detecting device 1 according to the first embodiment of the present invention. Therefore, the description of the drive voltage generator 6, the controller 7, and the arithmetic unit 8 is omitted here.

With the above configuration, the DC motor 291 according to this embodiment can detect the rotation pulse 213 corresponding to the rotation angle of the rotating armature 84 and rotate the armature 84 to a desired angle. .

As described above, the rotation pulse detecting device 1 according to the first embodiment of the present invention shown in FIG. 1 is provided with the pulse detecting device 9 as the pulse detecting means. The pulse detection device 9 includes a resistor 2, a current detector 3 as a current detection means, and a rotation pulse generation circuit 4 as a rotation pulse generation means.

The resistor 2 is connected in parallel with the winding wire 85a between specific segments 83a, b of the plurality of segments 83a, b, c formed in the commutator 83. Further, the current detector 3 is connected to the brush 82b on the cathode side, and the rotation pulse generation circuit 4 is further connected to the current detector 3.

Here, the resistance value of the entire circuit of the resistor circuit (not shown) formed by the resistor 2 and the windings 85a, 85b, 85c changes in accordance with the rotation angle of the armature 84 so as to cause periodic fluctuations. To do. Therefore, the cathode side brush 82b
Also, the current flowing through changes with the rotation angle of the armature 84 with periodic fluctuations.

The current detector 3 is composed of the brush 8 on the cathode side.
It is configured to generate the current detection signal 10 in accordance with the magnitude of the current flowing through 2. Further, the rotation pulse generation circuit 4 is configured to generate the rotation pulse 13 from the current detection signal 10.

Therefore, according to the rotation pulse detecting apparatus 1 in the first embodiment of the present invention, the current flowing between the specific segments 83a, b among the plurality of segments 83a, b, c formed in the commutator 83 is reduced. Based on this, the rotation pulse 13 according to the rotation angle of the armature 84 can be detected, and a large-scale sensor such as a rotary encoder conventionally used can be eliminated.

The rotation pulse detecting device 101 according to the second embodiment of the present invention shown in FIG. 2 is provided with a pulse detecting device 109 as a pulse detecting means. This pulse detection device 109 includes an oscillator 102 and a current detector 3
And a rotation pulse generation circuit 1 as rotation pulse generation means
It is composed of 04.

The oscillator 102 is connected in parallel with the winding 85a between specific segments 83a, b of the plurality of segments 83a, b, c formed in the commutator 83. The current detector 3 is attached to the brush 82b on the cathode side.
Is connected to the current detector 3. Further, the rotation pulse generation circuit 104 is connected to the current detector 3.

Here, the oscillator 102 has an armature 8
The current flows only when 4 is at a given rotation angle. Further, the oscillator 102 is configured to superimpose an AC component having a specific frequency on the current flowing between the pair of brushes only when the current flows.

The current detector 3 is composed of the brush 8 on the cathode side.
2 is configured to generate the current detection signal 110 according to the magnitude of the current flowing through the device 2. Further, the rotation pulse generation circuit 104 receives the rotation pulse 11 from the current detection signal 110.
3 is generated.

Therefore, according to the rotation pulse detecting device 101 according to the second embodiment of the present invention, the current flowing between the specific segments 83a, b among the plurality of segments 83a, b, c formed in the commutator 83 can be reduced. Based on this, the rotation pulse 113 according to the rotation angle of the armature 84 can be detected, and a large-scale sensor such as a rotary encoder that has been conventionally used can be eliminated.

The rotation pulse detecting device 201 according to the third embodiment of the present invention shown in FIG. 3 is provided with a pulse detecting device 209 as a pulse detecting means. The pulse detection device 209 includes a light emitting element 202 and a light receiving element 2
03, and a rotation pulse generation circuit 204 as a rotation pulse generation means.

The light emitting element 202 is connected in parallel with the winding wire 85a between specific segments 83a, b among the plurality of segments 83a, b, c formed in the commutator 83. Further, a light receiving element 203 is arranged so that it can be optically coupled with the light emitting element 202. Further, the light receiving element 20
A rotation pulse generation circuit 204 is connected to the circuit 3.

Here, a current flows through the light emitting element 202 only when the armature 84 is at a predetermined rotation angle.
Further, the light emitting element 202 is configured to output the light emission signal 210 in a specific frequency band only when a current flows.

Also, the light receiving element 203 is the light emitting element 202.
It is configured to receive the light emission signal 210 output according to the presence or absence of energization and to detect the light reception signal 211.
Further, the rotation pulse generation circuit 204 is configured to generate the rotation pulse 213 from the light reception signal 211.

Therefore, according to the rotation pulse detecting device 201 of the third embodiment of the present invention, the current flowing between the specific segments 83a, b among the plurality of segments 83a, b, c formed in the commutator 83 is reduced. Based on this, it is possible to detect the rotation pulse 213 according to the rotation angle of the armature 84, and it is possible to eliminate the need for a large-scale sensor such as a rotary encoder that has been conventionally used.

Further, as shown in FIG. 6, when the diode 31 is connected in series with the resistor 2, the power consumed by the resistor 2 per one rotation of the armature 84 can be halved. .

Further, according to the DC motor 91 according to the first embodiment of the present invention shown in FIG. 13, the rotation pulse detecting device 1
Therefore, it is possible to accurately detect the rotation pulse 13 according to the rotation angle of the armature 84 without using a large-scale sensor such as a rotary encoder that has been conventionally used. A driven mechanism (not shown) connected can be adjusted to a desired angle.

Also, the DC motors 191 and 291 according to the second and third embodiments of the present invention, as well as the DC motor 91 according to the first embodiment of the present invention, have been used conventionally. It is possible to accurately detect the rotation pulses 113 and 213 according to the rotation angle of the armature 84 without using a large-scale sensor such as an encoder. Further, a driven mechanism (not shown) connected to the DC electric motors 191 and 291 is provided. It can be adjusted to a desired angle.

The embodiment of the present invention may be modified as follows. FIG. 14: is a block diagram which shows the structure of the 1st modification of the rotation pulse detection apparatus which concerns on 1st embodiment of this invention. FIG. 15: is a block diagram which shows the structure of the 2nd modification of the rotation pulse detection apparatus which concerns on 1st embodiment of this invention. FIG. 16 is a block diagram showing the configuration of the third modification of the rotation pulse detection device according to the first embodiment of the present invention. Hereinafter, modified examples of the embodiment of the present invention will be shown.

(Modification 1) As shown in FIG. 14, in the rotation pulse detecting device 1 according to the first embodiment of the present invention,
A filtering circuit 44 that removes noise in a specific frequency range may be connected to the subsequent stage of the amplifier circuit 41.

In this way, by connecting the filtering circuit 44 to the subsequent stage of the amplifier circuit 41, the amplifier circuit 41
The noise of the amplified signal 11 output from the device can be removed, and the rotation pulse 13 can be accurately output.

(Modification 2) As shown in FIG. 15, in the rotation pulse detecting device 1 according to the first embodiment of the present invention,
The rotation pulse generation circuit 4 may use the differentiating circuit 45 in the subsequent stage of the amplifying circuit 41. However, the output terminal of the differentiating circuit 45 must be connected to the positive input terminal of the comparing circuit 43.

By thus connecting the differentiating circuit 45 to the subsequent stage of the amplifying circuit 41, the comparing circuit 43 is used to compare the signal obtained by differentiating the amplified signal 11 by the differentiating circuit 45 with the amplified signal 11. The rotation pulse 13 can be generated.

(Modification 3) As shown in FIG. 16, in the rotation pulse detector 1 according to the first embodiment of the present invention,
A differentiating circuit 45 and an integrating circuit 46 may be connected to the rotation pulse generating circuit 4 after the amplifying circuit 41. However,
The output terminal of the differentiation circuit 45 needs to be connected to the plus side input terminal of the comparison circuit 43, and the output terminal of the integration circuit 46 needs to be connected to the minus side input terminal of the comparison circuit 43.

By connecting the differentiating circuit 45 and the integrating circuit 46 to the subsequent stage of the amplifying circuit 41 in this way, the comparing circuit 4
3 can be used to compare the signal obtained by differentiating the amplified signal 11 by the differentiating circuit 45 and the signal obtained by integrating the amplified signal 11 by the integrating circuit 46 to generate the accurate rotation pulse 13.

(Modification 4) The rotation pulse detecting device 1 according to the embodiment of the present invention may be applied to the armature 84 which can rotate in both directions.

That is, the well-known rotation direction detector capable of detecting the rotation direction of the armature 84 is used as the rotation pulse detection device 1.
In addition, a current detector similar to the current detector 3 is also connected to the brush 82a side.

The current detection signal detected by the current detector connected to the brush 82a side is also amplified by the amplifier circuit 4.
It is configured so that the rotation pulse 13 can be generated by inputting 1 to 1.

The rotation direction signal obtained from the rotation direction detector is input to the control device 7.

With the above-mentioned structure, the control device 7 can detect the rotation pulse 13 according to the rotation angle regardless of the direction of rotation of the armature 84.

Further, in the DC motor 91, when the armature 84 is configured to rotate in both directions, the rotary pulse detecting device 1 modified to the above-described configuration.
By using, the rotation pulse 13 according to the rotation angle is detected regardless of which direction the armature 84 rotates,
The armature 84 can be rotated to a desired angle.

The rotation pulse detecting devices 101 and 201
May be modified and configured similarly to the configuration of the rotation pulse detection device 1 modified as described above, and may be applied to the armature 84 that can rotate in both directions.

Further, in the DC motors 191 and 291, when the armature 84 is configured to rotate in both directions, by using the rotary pulse detecting devices 101 and 201 modified to the above-described configuration, the armature is Regardless of which direction the 84 rotates, the rotation pulses 113 and 213 according to the rotation angle can be detected, and the armature 84 can be rotated to a desired angle. (Modification 5) In the rotation pulse detection device 1 according to the first embodiment of the present invention, a Hall element may be used instead of the resistor 3.

By using the Hall element in this way,
A good current detection signal 10 having high frequency characteristics can be obtained.

[0229]

As described above, according to the present invention, the rotation pulse according to the rotation angle of the armature can be accurately detected without using a large-scale sensor such as a rotary encoder.

Further, it is possible to accurately detect the rotation pulse according to the rotation angle of the armature without using a large-scale sensor such as a rotary encoder. Further, a driven mechanism (not shown) connected to this DC motor is desired. The angle can be adjusted.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a rotation pulse detection device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a rotation pulse detection device according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a rotation pulse detection device according to a third embodiment of the present invention.

FIG. 4 is a circuit diagram showing a low pass filter according to an embodiment of the present invention.

FIG. 5 is a circuit diagram showing an integrating circuit according to an embodiment of the present invention.

FIG. 6 is a diagram showing a partial configuration of a DC motor according to the first embodiment of the present invention.

FIG. 7 is a diagram showing a rotating state of the DC motor according to the first embodiment of the present invention.

FIG. 8 is a diagram showing a rotating state of the DC motor according to the first embodiment of the present invention.

FIG. 9 is a diagram showing a rotation pulse generation process by the rotation pulse detection device according to the first embodiment of the present invention.

FIG. 10 is a diagram showing a rotation pulse generation process by the rotation pulse detection device according to the first embodiment of the present invention.

FIG. 11 is a diagram showing a rotation pulse generation process by the rotation pulse detection device of the second embodiment of the present invention.

FIG. 12 is a diagram showing a rotation pulse generation process by the rotation pulse detection device of the third embodiment of the present invention.

FIG. 13 is a block diagram showing a configuration of a DC motor according to the first embodiment of the present invention.

FIG. 14 is a block diagram showing a configuration of a first modified example of the rotation pulse detection device according to the first embodiment of the present invention.

FIG. 15 is a block diagram showing the configuration of a second modification of the rotation pulse detection device according to the first embodiment of the present invention.

FIG. 16 is a block diagram showing a configuration of a third modified example of the rotation pulse detection device according to the first embodiment of the present invention.

FIG. 17 is a diagram showing a rotation pulse generation process in the prior art.

[Explanation of symbols]

1,101,201 Rotation pulse detector, 2,42a
Resistor, 3 Current detector, 4, 104, 204 Rotation pulse generation circuit, 6 Driving voltage generator, 7 Control device, 8 Arithmetic device, 10, 110 Current detection signal, 1
1,111 amplified signal, 12,312a, 312b comparison signal, 13,13a, 113,113a, 213,2
13a, 313, 313a, 313b rotation pulse, 1
4 rotation angle command pulse, 15 control signal, 16 drive voltage, 31 diode, 41 amplifier circuit, 42b operational amplifier, 42c capacitor, 42 comparison signal generation circuit, 43 comparison circuit, 44, 144 filtering circuit, 45 differentiation circuit, 46, 48 , 145 integration circuit,
47 low-pass filter, 81 motor section, 82a, b
Brush, 83 commutator, 83a, b segment, 84 armature, 85a, b, c winding, 86
Yoke housing, 87 magnets, 88 cores, 89 bearings, 90 rotating shafts, 91, 191,291 DC motors, 102 oscillators, 118 AC signals, 119 smoothing signals, 120 AC components, 146 waveform shaping circuits, 2
02 light emitting element, 203 light receiving element, 210 light emitting signal, 211 light receiving signal, 311 current ripple

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2F077 AA21 CC02 PP00 TT02 TT05                       TT32 TT35 VV01                 2F103 BA43 DA01 DA13 EA13 EB06                       EB12                 5H571 AA03 BB10 CC02 EE02 GG02                       HA08 HA16 JJ03 JJ17 JJ22                       JJ26 KK06 LL08 LL22 PP04

Claims (6)

[Claims] 1. A rotation pulse detection device in a DC electric motor comprising at least a pair of brushes, an armature in which a commutator and a winding are arranged, and a yoke housing which accommodates the armature, the rotation pulse detection device. The device comprises a pulse detection means for detecting a rotation pulse based on an electric current flowing between specific segments among a plurality of segments formed in the commutator. 2. The pulse detecting means includes a resistor connected in parallel with the winding between the specific segments, a current detecting means connected in series to the cathode side of the pair of brushes, and the current. The rotation pulse detection device according to claim 1, further comprising a rotation pulse generation means connected to the detection means. 3. The pulse detection means includes an oscillator connected in parallel with the winding between the specific segments, a current detection means connected in series to the cathode side of the pair of brushes, and the current detection means. The rotation pulse detecting device according to claim 1, further comprising: a rotation pulse generating means connected to the means. 4. The pulse detecting means includes a light emitting element connected in parallel with the winding between the specific segments, a light receiving element optically coupled to the light emitting element, and a rotation pulse connected to the light receiving element. The rotation pulse detection device according to claim 1, further comprising a generation unit. 5. The rotating pulse detecting device according to claim 2, further comprising a diode connected in series with the resistor. 6. A DC electric motor using the rotation pulse detecting device according to any one of claims 1 to 5.