JP2003169493A - Motor controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To remove the influence of an electromagnetic field on a transformer in a motor controller for superposing, separating and transmitting rotary position information of a servo motor to a pair of (two) power lines. <P>SOLUTION: The transformer for superposing and separating the rotary position information of the servo motor contained in a motor position detector 11 or a motor driver 12 of the motor controller for superposing, separating and transmitting the rotary position information of the servo motor to the pair of (two) power lines is sealed to remove the influence of the electromagnetic field on the transformer 1. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a pair (2) of rotational position information of servo motors used in industrial robots and the like.
The present invention relates to a motor control device that transmits via a power supply line.

[0002]

2. Description of the Related Art There is a system in which rotational position information of a servo motor is transmitted via a pair (two) power supply lines by AC coupling of a signal winding and an electric wire winding by a transformer.

[0003]

In the above-described conventional motor control device, the transformer is used for superimposing and separating the signal on the power supply line (transmission line). Therefore, an electromagnetic field from the outside is applied to the transformer. If this happens, the signal may not be transmitted due to noise intrusion into the signal or a decrease in the magnetic permeability of the core due to the electromagnetic field. It is an object of the present invention to provide a motor control device capable of removing the influence of an electromagnetic field from the outside and transmitting the rotational position information of the motor by the electromagnetic field from the outside.

[0004]

In order to solve this problem, a motor control device of the present invention includes a motor position detector and
It has a motor driver connected to the motor position detector by a power cable having a pair of electric wires, supplies control power from the motor driver to the motor position detector via the power cable, and In a motor control device that transmits information for driving a motor between motor drivers via a power cable, an iron plate for a transformer for superimposing or separating the signal for driving the motor on the power cable. It is a motor control device that shields in the case of
By covering with a shield material, the invasion and influence of electromagnetic fields are eliminated.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION To solve this problem, a motor control device of the present invention has a motor position detector and a motor driver connected to the motor position detector by a power cable having a pair of electric wires, Motor control that supplies control power from the motor driver to the motor position detector via the power cable, and also transmits information for driving the motor between the motor position detector and the motor driver via the power cable. In the device, it is a motor control device that shields a transformer for superimposing signals on the power cable or separating signals with a steel plate case in the device, and by covering the transformer with a shield material Eliminate the invasion and influence of electromagnetic fields.

Further, according to the present invention, the shield of the transformer is covered with a resin mixed with a shield material to carry out the shield. Further, in the present invention, the transformer shield may be covered with a tape, cloth, or tube having a shielding effect. Further, in the present invention, the substrate on which the transformer is mounted may be a multilayer substrate, and one layer may be GND. Further, in the present invention, the shield may be applied to the whole of either one of the motor position detector that houses the transformer and the motor driver.

[0007]

EXAMPLES Example 1 Hereinafter, examples of the present invention will be described with reference to the drawings.

FIG. 6 is a motor control device in which the rotational position information of the servo motor is transmitted through a pair of (two) power supply lines by AC coupling of the transformer of the signal winding and the power supply winding of this embodiment. It is a block diagram of.

The motor control device is an encoder body,
It consists of a pair (two) of power lines and a motor driver body.

The encoder body has an encoder-side transformer d composed of one encoder-side signal winding a and two encoder-side power-source voltage supply windings c connected to two power-source voltage supply lines f. The driver is built in, and the driver body is composed of one driver-side signal winding part b and two driver-side power-voltage supplying winding parts c connected to two power-supply voltage supplying lines f. The side transformer e is built in.

The two electric wires serving as the encoder-side power supply voltage supply winding section c (or the driver-side power supply voltage supply winding section c) have a DC voltage of 5V, 0 which is an encoder-side control voltage.
V from the driver body to the encoder body, 1 from the power supply
Two lines are connected, one for 5V and one for 0V, and two driver side power supply voltage supply windings c, two power supply voltage supply lines f, two encoder side power supply voltage supply windings c Connect and supply.

Motor position information obtained by serially converting the motor position detection signal is differentially output by the line driver h by the transmission circuit having the line driver h and transmitted to the encoder side signal winding a.

The motor position detection signal is a total of six types of signals, namely, an A-phase signal, a B-phase signal, a Z-phase signal, and three types of CS signals. The motor position information is the six types of signals.
The signals of various types are serial-converted so that the six types of signals at constant time intervals can be transmitted as a single piece of information by a pair (two wires) of electric wires.

The motor position information transmitted to the encoder-side signal winding a is superimposed on the encoder-side power supply voltage supply winding c by the encoder-side transformer d by electromagnetic induction (AC coupling).

The motor position information superimposed on the two encoder side power supply voltage supply windings c is the two power supply voltage supply lines f.
Since the encoder side power supply voltage supply winding c connected to the side and the power supply voltage supply line f are connected, it is transmitted to the driver side power supply voltage supply winding c of the two driver side transformers e that are also connected. .

The motor position information transmitted to the two driver side power supply voltage supply windings c by the driver side transformer e is separated from one driver side signal winding into a driver side receiving circuit having a line receiver i. It takes in, decodes the motor position information of the serial signal, and takes in the motor as a parallel position motor position detection signal necessary for motor control to perform the motor control.

The feature of this embodiment is that at least one of the encoder-side transformer d and the driver-side transformer e is shielded. The details will be described below.

The transformer 1 is covered with a case 2 made of an iron plate (sheet metal), and the electric wire portion 3 is drawn out. With such a configuration, it is possible to prevent noise due to an electromagnetic field and a decrease in magnetic permeability of the core. Case 2 is GND or FG
It is more effective to connect to.

The transformer 1 is, as shown in FIG.
Even if it is covered with the resin case 4 and the electric wire portion 3 is pulled out, it is possible to prevent noise due to an electromagnetic field and a decrease in magnetic permeability of the core.

The transformer 1 is, as shown in FIG.
Even if the electric wire portion 3 is pulled out by covering with a shield member 5 covered with a tape, cloth, or tube having a shield effect,
It is possible to prevent noise due to electromagnetic fields and a decrease in magnetic permeability of the core.

(Embodiment 2) FIG. 4 is a motor control in which rotational position information of a servomotor is transmitted through a pair of (two) power supply lines by AC coupling of a signal winding and a power supply winding by a transformer. This is the transformer of the device, and when the transformer 1 is directly mounted on the motor substrate, one layer of the multilayer substrate 6 is GND.
The layer 7 is formed and the transformer 1 is mounted on the layer 7. Further, by covering the portion other than the mounting surface of the transformer 1 with the shield cover 8 of an iron plate case or a resin case, it is possible to prevent noise due to an electromagnetic field and a decrease in magnetic permeability of the core.

(Embodiment 3) FIG. 5 is a motor control in which the rotational position information of a servomotor is transmitted through a pair of (two) power lines by AC coupling of a signal winding and a power winding by a transformer. It is a motor position detector of the device, and a transformer 1
Motor position detector 11 and motor driver 1
By covering the whole of either one of the two devices with the shield covers 9 and 10 shielded with the case of an iron plate or a resin, it is possible to prevent noise due to an electromagnetic field and a decrease in the magnetic permeability of the core.

[0023]

According to the present invention, it is possible to prevent noise due to an electromagnetic field and a decrease in magnetic permeability of the core.

[Brief description of drawings]

FIG. 1 is a diagram showing a motor control device according to a first embodiment.

FIG. 2 is a diagram showing a transformer according to the first embodiment.

FIG. 3 is a diagram showing a transformer according to the first embodiment.

FIG. 4 is a diagram showing a transformer according to a second embodiment.

FIG. 5 is a diagram showing a motor position detector according to a third embodiment.

FIG. 6 is a configuration diagram of a motor control device according to the first embodiment.

[Explanation of symbols]

1 transformer 2 iron plate case 3 electric wires 4 resin case 5 Shield member 6 Multi-layer board 7 GND layer 8 shield cover 9 Motor position detector shield cover 10 Motor driver shield cover 11 Motor position detector 12 motor driver

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hirozo Tagami             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Taro Kishibe             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F-term (reference) 5E321 AA01 AA17 AA22 BB33 GG05                 5H560 AA07 DA07 RR10 SS01 TT08                       TT16 TT20

Claims (5)

[Claims] 1. A motor position detector and a motor driver connected to the motor position detector by a power cable having a pair of electric wires, and a control power source from the motor driver to the motor position detector via the power cable. In the motor control device that supplies the information for driving the motor between the motor position detector and the motor driver via the power cable, the signal for driving the motor is superimposed on the power cable. , Or a motor control device in which a transformer for signal separation is shielded by an iron plate case. 2. The motor control device according to claim 1, wherein the shield of the transformer is covered with a resin containing a shield material to carry out the shield. 3. The motor control device according to claim 1, wherein the transformer shield is covered with a tape, cloth, or tube having a shielding effect. 4. The motor control device according to claim 1, wherein the substrate on which the transformer is mounted is a multilayer substrate, and one layer is GND. 5. A motor position detector for housing a transformer,
The motor control device according to any one of claims 1 to 4, wherein the entire one of the motor drivers is shielded.