JPH0662322U - Absolute encoder device - Google Patents

Abstract

(57) [Abstract] [Purpose] It is possible to obtain highly accurate absolute position data of a detected object over multiple rotations with a simple configuration. [Configuration] During normal energization, while the multi-rotation absolute position data is created by using the highly accurate incremental position detection unit 12 with a simple configuration, immediately after switching from the power failure state to the energized state, the simple configuration is performed. Absolute position detection unit 13 is used to obtain relatively coarse in-revolution absolute position data, and a predetermined control operation is executed based on the relatively coarse in-revolution absolute position data. Then, when the power is switched from the power failure state to the energized state, the incremental position detection section 12 corrects the relatively coarse absolute position data within one rotation with high accuracy, and again the simple configuration makes it possible to perform the highly accurate incremental position detection section 12 again. Configured to create multi-turn absolute position data using.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an absolute encoder device that detects the absolute position of an object to be detected over multiple rotations.

[0002]

[Prior art]

 BACKGROUND ART Conventionally, in a brushless motor or the like, an encoder device has been used to detect the rotational position of a detected object. Of the encoder devices, the absolute encoder device is for detecting the absolute position of the object to be detected, and for example, as shown in FIG. 2, a multi-rotation detecting section for detecting the number of revolutions of the object to be detected over many revolutions. 1 and an absolute-in-one-rotation absolute position detector 2 that detects an absolute position within one rotation of the object to be detected.

In the example shown in FIG. 2, the two-phase detection output from the Hall elements 4 and 4 arranged to face the disc-shaped detection magnet 3 is applied to the multi-rotation detection unit 1. The rotation speed data is obtained by the multi-rotation detecting section 1 based on the outputs from the scroll elements 4 and 4. Further, for example, a detection output from the resolver 5 is applied to the within-one-revolution absolute position detection unit 2, and based on this, the within-one-revolution absolute position data is obtained. The rotational speed data and the absolute position data within one rotation, which are respectively output from the multiple rotation detection unit 1 and the absolute position within one rotation detection unit 2, are sent to the multiple rotation absolute position data creation unit 6, where the detected object Absolute position data over multiple revolutions can be obtained. This multi-rotation absolute position data is sent to a predetermined host device and used for position control, speed control, and various other controls.

[0004]

[Problems to be solved by the device]

 However, in the above-mentioned conventional absolute encoder device, it is necessary to correct the rotational position and temperature in order to obtain a predetermined positional accuracy, and therefore the entire device becomes complicated and it is difficult to reduce the size. .

Therefore, an object of the present invention is to provide an absolute encoder device capable of highly accurately obtaining absolute position data over multiple rotations of an object to be detected with a simple structure.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, an absolute encoder device according to the present invention includes an auxiliary power supply for a power failure, a multi-rotation detecting unit that detects the number of revolutions of a detection target over multiple rotations, and a detection target when energized. Incremental position detection unit that outputs a rotational position detection signal according to the rotational movement of the object together with the origin position instruction signal, and detects the absolute position within one rotation of the detected object when switching from the power failure state to the power supply state. The absolute position data of the object to be detected is created based on the detection signals from the absolute position detection unit, the multi-rotation detection unit, the incremental position detection unit, and the absolute position detection unit described above. A structure equipped with a multi-rotation absolute position data creation unit that corrects the origin by the origin position instruction signal from the incremental position detection unit. The it has.

[0007]

[Action]

 According to the absolute encoder device in such means, the multi-rotation absolute position data is created by counting the output of the highly accurate incremental position detection unit with a simple configuration and a high accuracy during normal energization, and at the same time, a power failure is generated. Immediately after switching from the state to the energized state, the absolute position in-revolution absolute position data with relatively high accuracy is obtained using the absolute position detection unit with a simple structure. A predetermined control operation is executed based on the data and the multi-rotation data from the multi-rotation detector. Then, when the power is switched from the power failure state to the energized state, the incremental position detection unit corrects the relatively coarse absolute position data within one rotation with high accuracy by the incremental position detection unit, and the highly accurate incremental position detection unit again with a simple configuration. Is used to create multi-rotation absolute position data.

[0008]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. The absolute encoder device according to the embodiment shown in FIG. 1 uses a rotating shaft of a brushless motor as a detected object, and is used in a control system for performing position control, speed control, etc. of the rotating shaft. It has a multi-turn detection unit 11 that detects the number of rotations of the rotary shaft over multiple revolutions, and an incremental position detection unit 12 that outputs a rotation position detection signal according to the rotational movement of the rotary shaft, and also has an auxiliary In addition, it has a single-revolution absolute position detection unit 13 with a simple configuration. Further, the detection output signals from the multi-rotation detecting unit 11, the incremental position detecting unit 12, and the in-one-turn absolute position detecting unit 13 are multi-rotation absolute position data creating units that create absolute position data over multiple revolutions of the rotary shaft. 14 has been input.

To the multi-rotation detector 11, two-phase outputs from two Hall elements 112, 112, which are arranged to face a disc-shaped detection magnet 111, are applied. The multi-rotation detection unit 11 is provided with a sensor circuit for counter-outputting the rotation speed data obtained based on the detection outputs of the elements 112, 112 to the multi-rotation absolute position data creation unit 14 described above. In addition, a backup battery 113 is attached to the multi-rotation detection unit 11 and the multi-rotation absolute position data creation unit 14 as an auxiliary power supply for a power failure.

Further, the incremental position detection unit 12 outputs a two-phase rotational position detection signal (A phase, B phase) corresponding to the rotational movement of the rotary shaft and an origin position instruction signal (Z phase) to the multi-rotation. An output from the magnetoresistive element (MR element) 122, which is arranged to face the magnetized outer peripheral surface of the cylindrical magnetic recording drum 121, is output to the absolute position data creation unit 14. The incremental position detector 12 is configured to operate only when the power is normally applied.

On the other hand, the absolute position detection unit 13 employs, for example, a Hall element output type resolver having a simple structure, and is arranged to face the disc-shaped detection magnet 111 of the multi-rotation detection unit 11. Two-phase outputs from the Hall elements 131, 131 of the body are applied. This Hall element output outputs one cycle of pseudo sine wave when the encoder makes one rotation. By comparing the voltages of the two hall element outputs that are 90 ° out of phase, You can know the absolute position of. The absolute position detection unit 13 operates when the power failure state is switched to the energized state, and outputs the absolute position within one rotation of the rotary shaft to the multi-rotation absolute position data generation unit 14. The absolute position data within one rotation is relatively coarse data having an error because the absolute position detection unit 13 has a simple structure. However, the absolute position data within one rotation is converted to the incremental position detection unit 12 described above. The multi-rotation absolute position data generation unit 14 is provided with a circuit for correcting the origin by the origin position instruction signal (Z phase) from the.

In the absolute encoder device according to such an embodiment, at the time of normal energization, first, the rotational position detection signals (A phase, B phase) from the incremental position detection unit 12 with a simple structure and high accuracy and Based on the origin position instruction signal (Z phase) and the rotation speed data from the multi-rotation detection unit 11, the multi-rotation absolute position data creation unit 13 creates absolute position data over multiple rotations of the rotary shaft.

On the other hand, at the time of power failure, only the multi-rotation detecting unit 11 is operated by the power supply from the backup battery 113, and the multi-rotation detecting unit 11 obtains the rotation speed data. This is to reduce power consumption and prolong battery backup time.

Next, when the power is switched from the power failure state to the energized state, the absolute position detecting unit 13 is operated in addition to the multi-rotation detecting unit 11, and the absolute position within one revolution of the rotary shaft is changed to the multi-rotation absolute position data creating unit. Obtained at 14. The absolute position data within one revolution is relatively coarse data that has an error because the absolute position detection unit 13 has a simple structure. However, based on the absolute position data within one revolution, immediately after energization, A predetermined control operation is executed, and the motor is rotated about once, for example.

When the incremental position detection unit 13 is operated by the above-described predetermined control operation and the origin position instruction signal (Z phase) from the incremental position detection unit 13 enters the multi-rotation absolute position data creation unit 14. The origin position signal (Z-phase) corrects the origin with respect to the relatively inaccurate one-revolution absolute position data at the time of switching from the power failure state to the energized state as described above and improves the accuracy. When this correction is completed, it is returned to the above-mentioned normal energization, multi-rotation absolute position data is created again using the highly accurate incremental position detection unit 12 with a simple configuration, and the predetermined control operation is continuously executed. It has become so.

As described above, according to the present embodiment, since highly accurate multi-rotation absolute position data can be obtained with a simple configuration, simplification and downsizing of the entire device can be achieved.

The above-mentioned incremental position detecting unit 12 may be an optical type, and the absolute position detecting unit 13 may be a winding type resolver having a simple structure. is there. Further, an optical type can be adopted as the multi-rotation detecting unit 11, and a circuit configuration can also be used which is also used as an absolute position detecting sensor within one revolution.

Although the invention made by the present inventor has been specifically described based on the embodiment, the invention is not limited to the above-mentioned embodiment, and various modifications can be made without departing from the gist of the invention. Needless to say.

[0019]

[Effect of device]

 As described above, the absolute encoder device of the present invention uses a highly accurate incremental position detection unit with a simple structure during normal energization, and a relatively coarse absolute position detection unit with a simple structure immediately after a power failure. Precise control operation is performed based on the absolute position data within one revolution of accuracy, and when the power is switched from the power failure state to the energized state, the origin is corrected by the incremental position detection unit to improve the accuracy. It is possible to perform highly accurate position detection while achieving miniaturization and miniaturization, and it is possible to enhance the reliability of the absolute encoder device.

[Brief description of drawings]

FIG. 1 is a block diagram of an absolute encoder device according to an embodiment of the present invention.

FIG. 2 is a block diagram of a conventional absolute encoder device.

[Explanation of symbols]

 11 Multi-Rotation Detection Unit 12 Incremental Position Detection Unit 13 Absolute Position Detection Unit 14 Multi-Rotation Absolute Position Data Creation Unit

Claims (1)

[Scope of utility model registration request] 1. A multi-rotation detecting unit that is equipped with an auxiliary power supply for a power failure and detects the number of revolutions of a detected body over multiple revolutions, and a rotational position detection signal according to the rotational movement of the detected body when energized, An incremental position detection unit that outputs together with an origin position instruction signal, and an absolute position detection unit that detects an absolute position within one rotation of the detected object when the power failure state is switched to the energized state, and the multi-rotation detection unit, The absolute position data of the object to be detected is created based on the detection signals from the incremental position detection unit and the absolute position detection unit, and the absolute position data is corrected by the origin position instruction signal from the incremental position detection unit. An absolute encoder device comprising: a rotation absolute position data creation unit.