JP2004338019A - Control device for single axis robot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the cost of a single axis robot and to improve reliability by avoiding a conversion circuit for converting position detection signals into pulse signals, being placed in undesirable environment. <P>SOLUTION: The single axis robot R using a linear motor, and a controller C can communicate each other through a communication means. The single axis robot R is provided with a position detector comprising an MR sensor 12 or the like for reading a magnetic scale 11, and detector output signals outputted from the position detector are inputted to the controller C through the communication means. Further, the conversion circuit 30 for converting the detector output signals comprising sinusoidal wave or cosine wave, into the pulse signals is provided in the controller C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a controller for a single-axis robot including a single-axis robot using a linear motor and a controller for controlling the driving of the single-axis robot.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as shown in Patent Literature 1, for example, there is provided a stator unit in which permanent magnets are arranged in an axial direction, and a movable member provided with a coil surrounding the stator unit, and energization of the coil is controlled. A linear motor is generally known in which a movable member moves linearly in a direction along an axis of a stator section. Such a linear motor is used for transporting articles in various fields and can be applied to a single-axis robot.
[0003]
Generally, this type of linear motor is provided with a position detector that detects the position of the movable member, and based on the detection by the position detector, the controller controls the energization of the coil to control the linear motor. It has become so.
[0004]
For example, in a single-axis robot R using a linear motor as shown in FIG. 4, a magnetic or optical scale 111 extending linearly is provided on the robot body, and the scale 111 is read to determine the position of the movable member. A position detection unit 120 including a sensor 112 for detecting the position of the sensor 112 and an amplifier 121 for amplifying the output of the sensor 112 is provided on the movable member. Further, the single-axis robot R is integrally provided with a conversion circuit 130 for converting a signal composed of a sine wave or a cosine wave output from the sensor 112 via the amplifier 121 into a pulse signal. A controller C for controlling the single-axis robot R is installed at an appropriate place away from the single-axis robot R, and a communication cable 125 is connected between the controller C and the single-axis robot R, and the conversion is performed. The position detection data converted by the circuit 130 is input to the controller C via the communication cable 125.
[0005]
[Patent Document 1]
Japanese Patent Publication No. 5-34902
[Problems to be solved by the invention]
According to the structure as shown in FIG. 4, it is necessary to equip the single-axis robot R with a unit constituting the conversion circuit 130 separately from the position detection unit 120, and further, a housing or the like for protecting the unit of the conversion circuit 130 Need to be provided integrally, the cost of the single-axis robot R increases. In addition, the single-axis robot R is in an environment that is not preferable for an electronic circuit due to a rise in temperature and vibration, and the controller C is installed at a remote place with respect to the single-axis robot R. Is provided in the undesired environment because it is provided on the single-axis robot R side, and may be affected by heat or the like.
[0007]
The present invention has been made to solve such a problem, and can reduce the cost of a single-axis robot, and avoid placing a conversion circuit that converts a position detection signal in an unfavorable environment, It is an object of the present invention to provide a control device for a single-axis robot capable of improving the performance.
[0008]
[Means for Solving the Problems]
The present invention includes a single-axis robot using a linear motor, and a controller for controlling the driving of the single-axis robot. The single-axis robot and the controller can communicate with each other via communication means. A control device for a single-axis robot provided with a position detector for magnetically or optically detecting a position of the axis robot, wherein the detector comprises a sine wave or a cosine wave output from the position detector. An output signal is input to the controller via the communication means, and a conversion circuit for converting the detector output signal into a pulse signal is provided in the controller.
[0009]
According to the present invention, a conversion circuit for converting a detector output signal consisting of a sine wave or a cosine wave into a pulse signal is not provided on the single-axis robot side, but in a controller installed at a place remote from the single-axis robot. , It is possible to prevent the influence of heat and vibration generated in the single-axis robot from affecting the conversion circuit. In addition, since the conversion circuit is removed from the single-axis robot, the structure of the single-axis robot is simplified, and since the conversion circuit is included in the controller, it is necessary to provide a separate unit for forming the conversion circuit. Absent.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings.
[0011]
FIGS. 1 and 2 show the structure of a single-axis robot to which the present invention is applied. In these figures, a single-axis robot R has a robot main body 1 and a linearly-movable linear direction with respect to the robot main body 1. And a movable member 2 that can be moved.
[0012]
The robot body 1 includes a base portion 3 and a pair of cover members 4 forming both side wall portions, and is formed in a horizontally long frame shape extending in one axial direction.
[0013]
In the robot main body 1, a guide rail 5 having a fixed width is provided on the base portion 3, and a stator portion 6 is disposed above the guide rail 5. The stator portion 6 has a plurality of annular permanent magnets 6a arranged in the axial direction such that N and S magnetic poles are alternately located in opposite directions, and is formed in a shaft shape. It is supported by the main body 1.
[0014]
Further, the movable member 2 has a hollow movable block 8 through which the stator section 6 is inserted, and a guided section 9 that engages with the guide rail 5 is provided at a lower end of the movable block 8, whereby the above-described section is provided. The movable block 8 is slidably supported by the guide rail 5.
[0015]
A coil 7 constituting an armature is fixed to the inner periphery of the hollow portion of the movable block 8. The coil 7 surrounds the stator 6 in a state where the movable member 2 is assembled to the robot body 1.
[0016]
A work member supporting table 10 is provided on the upper part of the movable member 2, and various work members according to the use are mounted on the table 10. The table 10 is attached to the movable block 8 by bolting or the like.
[0017]
Further, the single-axis robot R is provided with a position detector for detecting a position magnetically or optically. In this embodiment, the position detector is constituted by an MR sensor 12 that reads the magnetic scale 11.
[0018]
The magnetic scale 11 is provided on the upper surface of the base 3 on one side of the guide rail 5 over substantially the entire length of the base 3. On the other hand, the MR sensor 12 is arranged at the lower end of one side of the movable block 8 so as to face the magnetic scale 11. Note that a magnetic shield 13 is provided above the MR sensor 12 to prevent magnetic effects from the stator unit 6 and the coil 7 from affecting the MR sensor 12. A connector 16 is provided on one side surface of the table 10 of the movable member 2, and the MR sensor 12 is connected to the connector 16 via an electric wire or the like. A connector 18 provided at one end of a cable (not shown) accommodated in a flexible duct 17 is connected to the connector 16, and the other end of the cable is connected to a communication cable 25 (to be described later). Can be connected via.
[0019]
FIG. 3 shows a configuration of a control device for controlling the single-axis robot R. In this figure, a single-axis robot R is equipped with a position detecting unit 20. The position detecting unit 20 reads the magnetic scale 11 to detect a position, and amplifies the output of the MR sensor 12. And an amplifier 21 to be provided. Then, a signal composed of a sine wave or a cosine wave is output from the MR sensor 12 via the amplifier 21.
[0020]
A controller C for controlling the single-axis robot R is provided outside the single-axis robot R. The controller C is installed at a position away from the single-axis robot R, and the controller C and the position detection unit 20 are connected by a communication cable 25 (communication means).
[0021]
A conversion circuit 30 for converting a detector output signal (a signal output from the MR sensor 12 via the amplifier 21) into a pulse signal is provided in the controller C. The conversion circuit 30 converts a signal consisting of a sine wave or a cosine wave into a pulse signal having a period corresponding to the signal. Then, in the controller C, the position of the movable member 2 of the single-axis robot R is obtained from the position detection data including the pulse signal output from the conversion circuit 30, and the control amount is obtained based on the position. A control signal is output to the robot R.
[0022]
According to the apparatus of the present embodiment as described above, the magnetic scale 11 is read by the MR sensor 12 during the operation of the single-axis robot, and a signal consisting of a sine wave or a cosine wave is output from the position detection unit 20 accordingly. Then, the detector output signal is input to the controller C via the communication cable 25 as it is. Then, the output signal of the detector is converted into a pulse signal by the conversion circuit 30 in the controller C, and is used for controlling the single-axis robot R.
[0023]
By providing the conversion circuit 30 in the controller C in this way, the structure of the single-axis robot R is simplified as compared with the conventional structure provided on the single-axis robot side, and the cost of the single-axis robot R is reduced. This is advantageous.
[0024]
Further, since the conversion circuit 30 including the electronic circuit is separated from the single-axis robot R, it is avoided that the conversion circuit 30 is placed in an unfavorable environment for the electronic circuit. To the conversion circuit 30 is avoided.
[0025]
In the above embodiment, the position detection in the single-axis robot R composed of a linear motor is performed by magnetic means using the magnetic scale 11 and the MR sensor 12, but the position detection is performed by an optical scale and a sensor. You may do so. Also in this case, a signal consisting of a sine wave or a cosine wave is output from the sensor via an amplifier or the like, and a conversion circuit for converting this signal into a pulse signal is provided in the controller, as in the above embodiment.
[0026]
【The invention's effect】
As described above, according to the present invention, a single-axis robot using a linear motor and a controller that controls the single-axis robot can communicate with each other via communication means, and the single-axis robot has a position detector. In the apparatus, a conversion circuit for converting a signal output from the position detector into a pulse signal is provided in the controller, so that the structure of the single-axis robot can be simplified and the cost can be reduced. At the same time, it is possible to prevent the influence of heat or the like generated in the single-axis robot from affecting the conversion circuit and improve the reliability.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an example of a single-axis robot to which the present invention is applied.
FIG. 2 is a cross-sectional view of the single-axis robot.
FIG. 3 is a block diagram illustrating a schematic configuration of a control device for a single-axis robot according to an embodiment of the present invention.
FIG. 4 is a block diagram showing a conventional example.
[Explanation of symbols]
R Single-axis robot 11 Magnetic scale 12 MR sensor 20 Position detection unit C Controller 25 Communication cable 30 Conversion circuit

Claims (1)

A single-axis robot using a linear motor and a controller for controlling the driving of the single-axis robot are provided.The single-axis robot and the controller can communicate with each other via communication means. A single-axis robot control device provided with a position detector that magnetically or optically detects the position,
A detector output signal consisting of a sine wave or a cosine wave output from the position detector is input to the controller via the communication means,
A control device for a single-axis robot, wherein a conversion circuit for converting the detector output signal into a pulse signal is provided in the controller.

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