JP3515389B2 - Power supply for rotary encoder - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary encoder power supply device for supplying DC power to a rotary encoder mounted on a rotary electric machine.

[0002]

2. Description of the Related Art When a rotating electric machine such as an electric motor is operated by an inverter device, the rotary position of the electric motor is detected by a rotary encoder, and an AC sine is supplied to the electric motor by the inverter device based on a pulse signal from the rotary encoder. I'm trying to create waves. In this case, in a production line such as a factory, the distance between the electric motor and the inverter device that controls the operation of the electric motor is often significantly increased. Therefore, the rotary encoder directly connected to the electric motor and the DC The distance to the DC power supply device that supplies power also inevitably increases.

[0003]

SUMMARY OF THE INVENTION In the above conventional configuration,
If the distance between the rotary encoder and the DC power supply becomes long, it is necessary to use long positive and negative power supply lines that connect them, and the rotary encoder will operate normally due to the voltage drop due to the positive and negative power supply lines. It sometimes stopped working. That is, for example, when a rotary encoder rated at 5V is used, the power supply specification is 5V ± 0.
This is because it is as severe as 5 V (may be 5 V ± 0.25 V) and the power supply voltage cannot be increased unnecessarily.

It is also conceivable to use a rotary encoder having a rating of 15V in which a voltage drop due to the positive and negative power supply lines is not a problem, instead of the rotary encoder having a rating of 5V, but a differential encoder having excellent noise resistance is used. Since a rotary encoder of the 5V rating is generally used, 1
An alternative to a 5V rated rotary encoder is not practical.

Therefore, it is conceivable to separately provide the DC power supply device in the vicinity of the electric motor, that is, the rotary encoder, which is separated from the inverter device. However, in this case, the DC power supply is turned on and off with respect to the rotary encoder, and the voltage is adjusted by measuring the voltage of the DC power supply device. There is a problem that the operability of becomes worse.

The present invention has been made in view of the above circumstances, and a first object thereof is to reduce the voltage drop of one of the positive and negative power supply lines for supplying DC power from the DC power supply to the rotary encoder. It is an object of the present invention to provide a power supply device for a rotary encoder that can measure on the DC power supply side.

A second object of the present invention is to provide a power supply device for a rotary encoder capable of measuring the power supply voltage between the positive and negative power supply terminals of the rotary encoder on the DC power supply device side.

A third object of the present invention is to make it possible for the DC power supply unit to automatically correct the voltage drop on the positive and negative power supply lines for supplying DC power from the DC power supply unit to the rotary encoder. It is to provide a power supply device for an encoder.

[0009]

According to a first aspect of the present invention, there is provided a rotary encoder power supply device which has a positive power supply line connected to a positive power supply terminal and a negative power supply terminal of a rotary encoder which outputs a signal in accordance with rotation of a rotary electric machine. And a DC power supply having a positive power supply terminal and a negative power supply terminal for supplying DC power through a negative power supply line, and the DC power supply includes a positive power supply terminal and a negative power supply of the rotary encoder. A detection terminal to which a detection line connected to one of the terminals is connected is connected to one of the positive side power supply terminal and the negative side power supply terminal.
This detection terminal and the positive side power supply terminal are provided in the vicinity of
And a resistor connected to one of the negative side power supply terminal and the negative side power supply terminal .

According to this structure, the voltage generated between the detection terminal and one of the positive power supply terminal and the negative power supply terminal indicates the voltage drop of one of the positive power supply wire and the negative power supply line. Therefore, the voltage drop of one of the positive and negative power supply lines can be measured on the DC power supply side.

[0011] Power supply device of the rotary encoder according to claim 2, in a DC power supply, an auxiliary terminal is provided, based on the voltage generated between one of the detection terminals and the positive power supply terminal or the negative side power supply terminal In addition, an arithmetic circuit is provided which creates a potential obtained by subtracting twice the voltage from the potential of one of the positive side power supply terminal and the negative side power supply terminal of the rotary encoder and applies it to the auxiliary terminal.

According to this structure, the electric potential of the auxiliary terminal is changed from the electric potential of one of the positive power supply terminal and the negative power supply terminal of the rotary encoder to the detection terminal and one of the positive power supply terminal and the negative power supply terminal. The voltage between the auxiliary terminal and the other of the positive side power supply terminal and the negative side power supply terminal is
The DC power supply voltage between the positive and negative power supply terminals of the rotary encoder becomes the DC power supply voltage between the positive and negative power supply terminals of the rotary encoder, which can be measured on the DC power supply side.

According to a third aspect of the present invention, there is provided a rotary encoder power supply device in which a positive side power source line and a negative side power source line are provided to the positive side power source terminal and the negative side power source terminal of the rotary encoder which outputs a signal in accordance with the rotation of the rotary electric machine. A DC power supply device having a positive power supply terminal and a negative power supply terminal for supplying DC power via the DC power supply device is provided, and the DC power supply device is connected to the positive power supply terminal and the negative power supply terminal of the rotary encoder, respectively. positive detection line and the positive-side detection terminal and a negative-side detection terminal the positive power supply terminal negative detection line is connected
Provided in the vicinity of the child and the negative side power supply terminal, these positive
Detection terminal and negative side detection terminal and the positive side power supply terminal
And a resistor connected between the negative side power supply terminal and the negative side power supply terminal .

According to such a configuration, the voltage between the positive side power supply terminal and the positive side detection terminal shows the voltage drop of the positive side power supply line, and the negative side power supply terminal and the negative side detection terminal. The voltage between the terminals and the negative side power supply line shows the voltage drop, so the voltage between the positive and negative detection terminals becomes the power supply voltage between the positive and negative power supply terminals of the rotary encoder. The power supply voltage between the positive and negative power supply terminals of the rotary encoder can be measured on the DC power supply side.

According to a fourth aspect of the present invention, there is provided a rotary encoder power supply device in which a positive side power source line and a negative side power source line are provided to the positive side power source terminal and the negative side power source terminal of the rotary encoder which outputs a signal in accordance with the rotation of the rotary electric machine. A DC power supply device having a positive power supply terminal and a negative power supply terminal for supplying DC power via the DC power supply device, and the DC power supply device provides a DC output voltage between the positive power supply terminal and the negative power supply terminal. Mainly composed of a voltage regulator, the DC power supply device is provided with a detection terminal to which a detection line connected to one of a positive power supply terminal and a negative power supply terminal of the rotary encoder is connected, and 2 of the voltage generated between one of the positive power supply terminal and the negative power supply terminal
A correction circuit for generating a doubled voltage and feeding it back to the voltage regulator to correct the DC output voltage is provided.

According to such a configuration, the voltage regulators of the DC power supply device are fed back with the voltage drop components of both the positive and negative power source lines, so that the voltage regulator components are supplied with the voltage drop components. The corrected DC output voltage is output, so that the rated DC power supply voltage is automatically corrected and supplied between the positive power supply terminal and the negative power supply terminal of the rotary encoder.

In the rotary encoder power supply device according to a fifth aspect of the present invention, the voltage regulator is configured to control the DC output voltage at a constant level by feeding back a divided voltage value obtained by dividing the DC output voltage. Gain adjusting means for adjusting the divided voltage value is provided, and the voltage from the correction circuit is added to the divided voltage value. According to this structure, the same effect as that of the fourth aspect can be obtained, and further, the variable voltage DC power supply can be easily produced by the DC power supply device.

According to a sixth aspect of the present invention, there is provided a rotary encoder power supply device in which a positive side power source line and a negative side power source line are connected to the positive side power source terminal and the negative side power source terminal of the rotary encoder, which output signals in accordance with the rotation of the rotary electric machine. A DC power supply device having a positive power supply terminal and a negative power supply terminal for supplying DC power via the DC power supply device, and the DC power supply device provides a DC output voltage between the positive power supply terminal and the negative power supply terminal. A positive side detection terminal, which is mainly composed of a voltage regulator, and to which the positive side detection line and the negative side detection line connected to the positive side power source terminal and the negative side power source terminal of the rotary encoder are connected to the DC power supply device, respectively. And a negative side detection terminal are provided, and the voltage regulator outputs DC voltage by feeding back a divided voltage value obtained by dividing the voltage between the positive side detection terminal and the negative side detection terminal. Characterized in that it is configured to correct a voltage. With such a configuration, the same effect as that of claim 4 can be obtained.

According to a seventh aspect of the present invention, there is provided a rotary encoder power supply device including a gain adjusting means for adjusting a partial pressure value. According to such a configuration, claim 5
The same effect as can be obtained.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described below with reference to FIGS. First,
FIG. 2 shows a control system of an electric motor that is a rotary electric machine, for example, an induction motor. In FIG. 2, the inverter unit 1 is configured by integrating the inverter device 2, the pulse signal receiving circuit 3, and the DC power supply device 4.
In the inverter device 2, its input terminals R, S, T are connected to a three-phase AC power source 5, and output terminals U, V, W are input terminals of a three-phase induction motor 9 via feeder lines 6, 7, 8. It is connected to the.

The induction motor 9 is provided with a rotary encoder 10 having a coding disc directly connected to its rotary shaft, and its output terminal is provided with a pulse signal receiving circuit 3 via signal lines 11, 12 and 13. Is connected to the input terminal of. In this case, the rotary encoder 10 generates A, B, and Z phase pulses in response to the rotation of the rotor of the induction motor 9, and the A, B, and Z phase pulses are respectively different as shown in FIG. It is adapted to be applied to the differential receivers 17, 18, 19 of the pulse signal receiving circuit 3 via the dynamic drivers 14, 15, 16 and the pair of signal lines 11, 12, 13. And the differential receivers 17, 18,
The A, B, and Z phase pulses from 19 are supplied to the inverter device 2. The rotary encoder 10 having such a structure is referred to as a differential type having excellent noise resistance and is rated at 5V (power supply specification is 5V ± 0.5V.
Or 5V ± 0.25V) is common.

Therefore, the inverter device 2 applies an energizing signal to the switching element of the inverter circuit by PWM control based on the A, B and Z phase pulses given from the pulse signal receiving circuit 3 to output terminals U, V. ，
It is designed to output a three-phase AC voltage of a sine wave of variable frequency and variable voltage from W.
It is adapted to be supplied to the induction motor 9 via 8.

Now, the DC power supply device 4 will be described with reference to FIG. The DC power supply device 4 is mainly configured by a voltage regulator 20 including, for example, a switching regulator. In the voltage regulator 20, the power supply input terminal Vi is connected to the power supply line 21 of the DC voltage 24V, the positive side output terminal Vp is connected to the positive side power supply terminal Tp, and the negative side output terminal Vn is the negative side (ground side). ) It is connected to the power supply terminal Tn and also to the ground. The voltage dividing resistors 22 and 23 are connected in series between the output terminals Vp and Vn of the voltage regulator 20, and the common connection point is connected to the control terminal Vc of the voltage regulator 20.

The positive side power supply terminal Tp and the negative side power supply terminal Tn of the DC power supply device 4 are respectively connected to the positive side power supply terminal tp and the negative side (ground side) power supply terminal tn of the rotary encoder 10. They are connected via a power supply line 24 and a negative power supply line 25, and the DC power supply device 4, the positive power supply line 24, and the negative power supply line 25 constitute a power supply device 26 of the rotary encoder 10.

Further, the DC power supply device 4 is provided with a negative side detection terminal Tdn located near the negative side power supply terminal Tn, and the negative side detection terminal Tdn is connected to the negative side detection line 2.
Negative side power supply terminal tn of the rotary encoder 10 via
It is connected to the. Then, in the DC power supply device 4,
A resistor 28 is connected between the negative power supply terminal Tn and the negative detection terminal Tdn. In this case, the positive power line 2
4, the DC resistance components of the negative power supply line 25 and the negative detection line 27 are substantially equal, and the resistance value of the resistor 28 is set to be much larger than this.

Next, the operation of this embodiment will be described.
The voltage regulator 20 of the DC power supply device 4 has a power input terminal Vi.
The DC voltage of 24V applied to the output terminal Vp is adjusted by stepping down to output the DC power supply voltage of 5V between the output terminals Vp and Vn. In this case, the output voltage between the output terminals Vp and Vn is the voltage dividing resistor 22, By being divided by 23 and applied to the control terminal Vc, feedback control is performed so that the DC voltage output between the output terminals Vp and Vn always becomes the rated DC power supply voltage of the rotary encoder 10 of 5V.

Therefore, the DC power supply voltage output from the voltage regulator 20 passes through the positive and negative power supply terminals Tp and Tn, the positive and negative power supply lines 24 and 25, and the positive and negative sides of the rotary encoder 10. Side power supply terminal t
It is supplied between p and tn, whereby the rotary encoder 10 receives A, A according to the rotational position of the rotor of the induction motor 9.
B and Z phase pulses are output. in this case,
The DC power supply voltage supplied between the positive and negative power supply terminals tp and tn of the rotary encoder 10 due to the voltage drop due to the DC resistance of the positive and negative power supply lines 24 and 25 is 5V-0.5V (the power supply specification). Or 5V-0.25V)
If it is less than the limit, the rotary encoder 10 may not operate normally.

Therefore, for example, before starting the operation control by the inverter device 2 of the induction motor 9, the voltage measuring device 2
9, the voltage between the negative power supply terminal Tn and the negative detection terminal Tdn is measured. That is, the negative power supply terminal Tn
Between the negative side detection terminal Tdn and the negative side detection terminal Tdn, a resistor 28 having a resistance value much larger than the direct current resistance of the negative side power supply line 25 and the negative side detection line 27 is connected. Almost no current flows through the line 27, and the potential of the negative side detection terminal Tdn becomes equal to the potential of the negative side power supply terminal tn of the rotary encoder 10. Therefore, the voltage between the negative side power supply terminal Tn and the negative side detection terminal Tdn shows a voltage drop due to the DC resistance of the load side power supply line 25.

As a result, the worker can generate a voltage twice as high as the voltage measured by the voltage measuring device 29 (the positive and negative power supply lines 2).
The voltage regulator 20 by the voltage drop of both 4 and 25)
Of the voltage regulator 20 (eg, variable resistor) so that the DC output voltage between the output terminals Tp and Tn of the
Adjust.

As described above, according to this embodiment, the DC power supply device 4 is provided with the negative side detection terminal Tdn, and the negative side detection terminal Tdn and the negative side power supply terminal tn of the rotary encoder 10 are connected to the negative side detection line 27. And a resistor 28 having an extremely large resistance value is connected between the negative side power supply terminal Tn and the negative side detection terminal Tdn of the DC power supply device 4, and the negative side power supply terminal is connected. The voltage between Tn and the negative side detection terminal Tdn is measured. Therefore, by measuring the voltage between the negative-side power supply terminal Tn and the negative-side detection terminal Tdn, the voltage drop due to the negative-side power supply line 25 can be confirmed on the DC power supply device 4 side, and the positive and negative sides can be confirmed. Preliminary measures such as correction adjustment of the voltage drop of both the side power supply lines 24 and 25 can be performed. As a result, the DC power supply device 4 side can perform the measurement work, the adjustment work, and the DC power supply ON / OFF work, and the workability is excellent.

FIG. 4 shows a second embodiment of the present invention.
The same parts as those of the above are denoted by the same reference numerals, and different parts will be described below. In the second embodiment, the DC power supply device 4 is provided with a positive side detection terminal Tdp located near the positive side power supply terminal Tp, and this positive side detection terminal Tdp is similar to the negative side detection line 27. It is connected to the positive power supply terminal tp of the rotary encoder 10 via the positive detection line 30.
Further, the DC power supply device 4 is provided with a positive auxiliary terminal Tsp located near the positive detection terminal Tdp. A resistor 31 similar to the resistor 28 is connected between the positive power supply terminal Tp and the positive detection terminal Tdp.

The positive side detection terminal Tdp is connected to the ground via the series circuit of the resistor 32 and the capacitor 33, and the common connection point of the resistor 32 and the capacitor 33 is
It is connected to the inverting input terminal of the operational amplifier 35 via the resistor 34. Further, in the operational amplifier 35, the non-inverting input terminal is connected to the positive power supply terminal Tp via the resistor 36.
Connected to the ground via a resistor 37, and the output terminal is connected to the inverting input terminal via a resistor 38 and to the positive side auxiliary terminal Tsp via a resistor 39. ing. The arithmetic circuit 40 is configured as described above. The DC power supply device 4
In the above, in place of the voltage dividing resistor 22 of the first embodiment, a variable resistor 41 as gain adjusting means is provided.

In the second embodiment, the DC resistance component of the positive power supply line 24 is provided between the positive power supply terminal Tp and the positive detection terminal Tdp according to the same principle as in the first embodiment. A voltage corresponding to the voltage drop is generated, and the arithmetic circuit 40 applies a voltage twice this voltage to the positive power supply terminal Tp.
Create a potential subtracted from the potential of the positive side auxiliary terminal Td
It is supposed to be given to p.

Therefore, if the voltage measuring device 29 measures the voltage between the positive side power supply terminal Tp and the positive side auxiliary terminal Tdp, the voltage drop due to both the positive side power supply line 24 and the negative side power supply line 25 will be calculated. I can know. If the voltage measuring device 29 measures the voltage between the positive side auxiliary terminal Tdp and the negative side power supply terminal Tn, the rotary encoder 1
The DC voltage between the positive power supply terminal tp and the negative power supply terminal tn of 0 can be known.

Therefore, the operator uses a variable resistance based on the voltage drop due to both the positive and negative power supply lines 24 and 25 or the DC voltage between the positive and negative power supply terminals tp and tn of the rotary encoder 10. By adjusting the device 41, the DC voltage between the positive and negative power supply terminals tp and tn of the rotary encoder 10 is adjusted to the rated value of 5V.

As described above, according to the second embodiment, the positive side detection terminal Tdp and the positive side auxiliary terminal Ts are included in the DC power supply device 4.
p is provided, the positive side detection terminal Tdp and the positive side power supply terminal tp of the rotary encoder 10 are connected by the positive side detection line 30, and the positive side power supply terminal Tp and the positive side detection terminal of the DC power supply device 4 are further connected. A resistor 31 having an extremely large resistance value is connected between Tdp and Tdp, and based on the voltage between the positive-side power supply terminal p and the positive-side detection terminal Tdp, a voltage twice as high as the positive voltage is applied. The arithmetic circuit 40 is provided in which a potential obtained by subtracting from the potential of the side power supply terminal Tp is created and given to the positive auxiliary terminal Tsp.

Therefore, by measuring the voltage between the positive power supply terminal Tp and the positive detection terminal Tdp, the positive and negative power supply lines 24 and 25 on the DC power supply 4 side.
Can be confirmed, and by measuring the voltage between the positive side auxiliary terminal Tsp and the negative side power supply terminal Tn, the positive side and negative side power supply terminals tp and The DC voltage between tn can be confirmed, and the positive and negative power supply terminals tp of the rotary encoder 10 can be adjusted by adjusting the variable resistor 41.
It is possible to take a pre-treatment such as a correction adjustment of the DC voltage between tn and tn to the rated voltage.

FIG. 5 shows a third embodiment of the present invention.
The same parts as those in FIG. 4 are designated by the same reference numerals, and different parts will be described below. In the third embodiment, the DC power supply device 4 is provided with a positive side detection terminal Tdp and a negative side detection terminal Tdn, and the positive side detection terminal Tdn and the negative side detection terminal Tdn are connected to the positive side detection line 30. And the positive side power supply terminal tp and the negative side power supply terminal tn of the rotary encoder 10 via the negative side detection line 27,
A resistor 31 is connected between the positive power supply terminal Tp and the positive detection terminal Tdp, and a resistor 28 is connected between the negative power supply terminal Tn and the negative detection terminal Tdn. .

Therefore, in the third embodiment, the voltage between the positive side detection terminal Tdp and the negative side detection terminal Tdn is a DC voltage between the positive side power supply terminal tp and the negative side power supply terminal tn of the rotary encoder 10. Is
Therefore, by measuring the voltage between the positive side detection terminal Tdp and the negative side detection terminal Tdn on the DC power supply device 4 side with the voltage measuring device 29, the voltage between the positive side power supply terminal tp and the negative side power supply terminal tn of the rotary encoder 10 is increased. You can check the DC voltage. Moreover, since the arithmetic circuit 40 as in the second embodiment is unnecessary, there is an advantage that the circuit configuration is simple.

FIG. 6 shows a fourth embodiment of the present invention, which is shown in FIG.
The same parts as those of the above are denoted by the same reference numerals, and different parts will be described below. In this fourth embodiment, the first
The following configuration is added to the embodiment. That is, the negative side detection terminal Tdn is connected to the ground via the series circuit of the resistor 42 and the capacitor 43, and the common connection point of the resistor 42 and the capacitor 43 is the resistor 44.
Is connected to the inverting input terminal of the operational amplifier 45 via. Further, in the operational amplifier 45, the non-inverting input terminal is connected to the ground, and the output terminal is connected to the inverting input terminal via the resistor 46 and the resistor 47.
Is connected to the common connection point of the voltage dividing resistors 22 and 23 via. The correction circuit 48 composed of the inverting amplifier circuit is configured as described above.

Therefore, the voltage between both terminals of the resistor 28, which corresponds to the voltage drop of the negative power supply line 25, is amplified to a negative double voltage by the correction circuit 48 composed of the inversion amplifier circuit, and the voltage dividing resistor. 22 and 23 are provided at a common connection point. That is, since the voltage drop due to the positive and negative power supply lines 24 and 25 is given as a negative value to the voltage division value of the voltage dividing resistors 22 and 23, the voltage regulator 20 outputs the output voltage corresponding to the voltage drop. Therefore, the correction is automatically performed so as to increase the value, and therefore, the positive power supply terminal t of the rotary encoder 10 is increased.
A rated DC power supply voltage of 5 V is supplied between p and the negative power supply terminal tn.

As described above, according to the fourth embodiment, the correction circuit 48 creates and divides a negative double voltage from the voltage between both terminals of the resistor 28 corresponding to the voltage drop of the negative power supply line 25. Since it is given to the divided voltage value of the piezoresistors 22 and 23, the voltage regulator 20 automatically corrects so as to raise the output voltage by the amount of the voltage drop, and therefore the voltage measurement by the operator is performed. No need to adjust the voltage, which is extremely convenient for use.

FIG. 7 shows a fifth embodiment of the present invention, which is shown in FIG.
The same parts as those in FIG. 4 are designated by the same reference numerals, and different parts will be described below. In the fifth embodiment, the positive side detection terminal Tdp is connected to the ground via the series circuit of the resistor 49 and the capacitor 50, and the common connection point of the resistor 49 and the capacitor 50 is the resistor 51.
Is connected to the non-inverting input terminal of the operational amplifier 52. Further, in the operational amplifier 52, the inverting input terminal is connected to the positive power supply terminal Tp via the resistor 53, the inverting input terminal is connected to the ground via the resistor 54, and the output terminal is connected to the resistor 55. Is connected to the inverting input terminal via the resistor 56 and is also connected to the common connection point of the voltage dividing resistors 22 and 23 via the resistor 56. The correction circuit 57 including the inverting amplifier circuit is configured as described above.

Therefore, the voltage between both terminals of the resistor 31, which corresponds to the voltage drop of the positive power supply line 24, is amplified to a negative double voltage by the correction circuit 57 composed of the inversion amplifier circuit, and the voltage dividing resistor. 22 and 23 are provided at a common connection point. That is, the voltage drop due to the positive and negative power supply lines 24 and 25 is given as a negative value to the voltage division values of the voltage dividing resistors 22 and 23, so that the voltage regulator 20 outputs the voltage drop corresponding to the voltage drop. Therefore, the correction is automatically performed so as to increase the value, and therefore, the positive power supply terminal t of the rotary encoder 10 is increased.
A rated DC power supply voltage of 5 V is supplied between p and the negative power supply terminal tn. As a result, the same effects as those of the fourth embodiment can be obtained by the fifth embodiment.

FIG. 8 shows a sixth embodiment of the present invention.
The same parts as those of the above are denoted by the same reference numerals, and different parts will be described below. The sixth embodiment differs from the fourth embodiment (FIG. 6) in that a variable resistor 41 is provided instead of the voltage dividing resistor 22.

According to the sixth embodiment, the variable resistor 4
If the resistance value of 1 is adjusted, the voltage dividing value by the variable resistor 41 and the voltage dividing resistor 23 changes, so the voltage regulator 20
The DC output voltage from the DC power supply can also be adjusted and adjusted. Therefore, the same advantageous effects as in the fourth embodiment can be obtained, and a variable voltage DC power supply can be obtained from the DC power supply device 4.

FIG. 9 shows a seventh embodiment of the present invention, and FIG.
The same parts as those of the above are denoted by the same reference numerals, and different parts will be described below. In the seventh embodiment, the positive side output terminal Vp and the negative side output terminal Vn of the voltage regulator 20.
Are connected to the positive power supply terminals Tp and Tn, respectively. A series circuit of voltage dividing resistors 22 and 23 is connected between the positive side detecting terminal Tdp and the negative side detecting terminal Tdn, and a common connection point of these voltage dividing resistors 2 and 23 is a resistor 58 and It is connected to the ground via the series circuit of the capacitor 59, and the common connection point of the resistor 58 and the capacitor 59 is the control terminal V of the voltage regulator 20.
connected to c.

However, as described in the third embodiment (FIG. 5), the positive side detection terminal Tdp and the negative side detection terminal Td are detected.
The voltage between n becomes the DC power supply voltage between the positive power supply terminal tp and the negative power supply terminal tn of the rotary encoder 10,
This voltage is divided by the voltage dividing resistors 22 and 23 and given to the control terminal of the voltage regulator 20 via the integrating circuit composed of the resistor 58 and the capacitor 59. Negative side detection terminal Td
The voltage between n, that is, the voltage between the positive-side power supply terminal tp and the negative-side power supply terminal tn of the rotary encoder 10 is the rated 5V.
So that the positive output terminal Vp and the negative output terminal V
The DC output voltage between n is automatically adjusted.

Therefore, according to the seventh embodiment, the same effect as that of the fourth embodiment can be obtained, and since the correction circuit 48 is not required, the circuit structure can be simplified. .

FIG. 10 shows an eighth embodiment of the present invention. The same parts as those in FIG. 9 are designated by the same reference numerals, and different parts will be described below. The eighth embodiment differs from FIG. 9 in that a variable resistor 41 is provided instead of the voltage dividing resistor 22 in FIG. With such a configuration, the same effect as that of the seventh embodiment can be obtained, and the same effect as that of the sixth embodiment can be obtained.

The present invention is not limited to the embodiments described above and shown in the drawings, and the following expansions and modifications are possible. The rotary encoder is not limited to the differential type, but may be a normal type. The present invention can be applied not only to induction motors that are electric motors but also to general rotary electric machines including generators.

[0052]

As is apparent from the above description, according to the power supply device for the rotary encoder of the present invention, the voltage drop of one of the positive and negative power supply lines can be measured on the side of the DC power supply device. Therefore, the work of voltage measurement, voltage adjustment, and power on / off can be facilitated.

Further, according to the power supply device for a rotary encoder of the present invention, the DC power supply voltage between the positive and negative power supply terminals of the rotary encoder can be measured at the DC power supply device side, so that the same effect as described above can be obtained. can get.

Further, according to the power supply device for the rotary encoder of the present invention, since the voltage drops of both the positive and negative power supply lines are fed back to the voltage regulator of the DC power supply device, the positive power supply of the rotary encoder is supplied. The rated DC power supply voltage is automatically corrected and supplied between the terminal and the negative power supply terminal, which eliminates the need for an operator to perform voltage measurement and voltage adjustment work.

[Brief description of drawings]

FIG. 1 is an electrical configuration diagram of essential parts showing a first embodiment of the present invention.

FIG. 2 is an electrical configuration diagram of the entire control system.

FIG. 3 is an electrical configuration diagram of a rotary encoder-related portion.

FIG. 4 is a view corresponding to FIG. 1 showing a second embodiment of the present invention.

FIG. 5 is a diagram corresponding to FIG. 1 showing a third embodiment of the present invention.

FIG. 6 is a diagram corresponding to FIG. 1 showing a fourth embodiment of the present invention.

FIG. 7 is a view corresponding to FIG. 1 showing a fifth embodiment of the present invention.

FIG. 8 is a view corresponding to FIG. 1 showing a sixth embodiment of the present invention.

FIG. 9 is a view corresponding to FIG. 1 showing a seventh embodiment of the present invention.

FIG. 10 is a view corresponding to FIG. 1 showing an eighth embodiment of the present invention.

[Explanation of symbols]

In the drawings, 1 is an inverter unit, 2 is an inverter device, 3 is a pulse signal receiving circuit, 4 is a DC power supply device, 9 is an induction motor (electric motor), 10 is a rotary encoder, 1
4 to 16 are differential drivers, 17 to 19 are differential receivers, 20 is a voltage regulator, 22 and 23 are voltage dividing resistors, 24 is a positive power supply line, 25 is a negative power supply line, and 26 is a power supply device. , 27 is a negative detection line, 28 is a resistor, 30 is a positive detection line, 31 is a resistor, 35 is an operational amplifier, 40 is an arithmetic circuit, 41 is a variable resistor (gain adjusting means), 45 is an operational amplifier, 48 Is a correction circuit, 52 is an operational amplifier, 57
Is a correction circuit, Tp is a positive power supply terminal, Tn is a negative power supply terminal, tp is a positive power supply terminal, tn is a negative power supply terminal,
Tdp is a positive side detection terminal, Tdn is a negative side detection terminal, Tsp
Indicates a positive side auxiliary terminal, and Tsn indicates a negative side auxiliary terminal.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoichi Goji 2121 Nobuo, Asahi-cho, Mie-gun, Mie Prefecture Mie Factory, Toshiba Corporation (56) Reference JP-A-7-286860 (JP, A) JP-A 7-270180 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) G01D 5/00-5/62 G06F 1/00 H02K 11/00

Claims (7)

(57) [Claims] 1. A positive-side power supply for supplying direct-current power to a positive-side power supply terminal and a negative-side power supply terminal of a rotary encoder that outputs a signal in response to rotation of a rotating electric machine, via a positive-side power supply line and a negative-side power supply line. comprising a DC power supply device having a terminal and a negative side power supply terminal, to the DC power supply device, wherein the detection terminal positive power supply terminal and one connected to the detection line of the negative power supply terminal of said rotary encoder is connected Positive power supply terminal and negative side
Provided near one of the power supply terminals , this detection terminal and
Between one of the positive power supply terminal and the negative power supply terminal
A rotary encoder power supply device characterized in that a resistor is connected to . 2. The DC power supply device is provided with an auxiliary terminal, and based on the voltage generated between the detection terminal and one of the positive-side power supply terminal or the negative-side power supply terminal, a voltage twice as high as that is applied to the positive encoder of the rotary encoder. 2. The power supply device for a rotary encoder according to claim 1, further comprising an arithmetic circuit that creates a potential subtracted from one of the side power supply terminal and the negative side power supply terminal and supplies the potential to the auxiliary terminal. 3. A positive power supply for supplying direct-current power to the positive power supply terminal and the negative power supply terminal of a rotary encoder that outputs a signal in accordance with the rotation of a rotating electric machine, via a positive power supply line and a negative power supply line. A DC power supply device having a terminal and a negative power supply terminal is provided, and a positive detection line and a negative detection line connected to the positive power supply terminal and the negative power supply terminal of the rotary encoder, respectively, are connected to the DC power supply device. The positive side detection terminal and the negative side detection terminal to the positive side power supply terminal and the negative side power supply terminal.
Provided near the supply terminal , these positive side detection terminal and negative side
Detection terminal, positive side power supply terminal and negative side power supply terminal
A power supply device for a rotary encoder, characterized in that resistors are respectively connected to the child . 4. A positive power supply for supplying DC power to a positive power supply terminal and a negative power supply terminal of a rotary encoder that outputs a signal in response to rotation of a rotating electric machine, via a positive power supply line and a negative power supply line. A direct current power supply device having a terminal and a negative side power supply terminal, the direct current power supply device is mainly composed of a voltage regulator for providing a direct current output voltage between the positive side power supply terminal and the negative side power supply terminal; The power supply device is provided with a detection terminal to which a detection line connected to one of the positive power supply terminal and the negative power supply terminal of the rotary encoder is connected, and the detection terminal, the positive power supply terminal, and the negative power supply terminal. And a correction circuit for generating a voltage twice as high as the voltage generated between the voltage regulator and one of them and feeding it back to the voltage regulator to correct the DC output voltage. Power supply device of the re-encoder. 5. The voltage regulator is configured to control the DC output voltage at a constant level by feeding back a voltage division value obtained by dividing the DC output voltage, and gain adjusting means for adjusting the voltage division value. 5. The rotary encoder power supply device according to claim 4, wherein the voltage from the correction circuit is added to the divided voltage value. 6. A positive power supply for supplying DC power to the positive power supply terminal and the negative power supply terminal of a rotary encoder that outputs a signal in accordance with the rotation of a rotating electric machine, via a positive power supply line and a negative power supply line. A direct current power supply device having a terminal and a negative side power supply terminal, the direct current power supply device is mainly composed of a voltage regulator for providing a direct current output voltage between the positive side power supply terminal and the negative side power supply terminal; The power supply device is provided with a positive side detection terminal and a negative side detection terminal to which a positive side detection line and a negative side detection line respectively connected to the positive side power source terminal and the negative side power source terminal of the rotary encoder are connected, and the voltage adjustment The device is configured to correct the DC output voltage by feeding back a divided voltage value obtained by dividing the voltage between the positive side detection terminal and the negative side detection terminal. Rotary encoder power supply device. 7. The power supply device for a rotary encoder according to claim 6, further comprising a gain adjusting means for adjusting a partial pressure value.