Distance measuring device and method thereof for seeking distance measuring starting point

Patent metadata

Field	Value
Publication number	US-11460328-B2
Application number	US-202016851020-A
Country	US
Kind code	B2
Filing date	Apr 16, 2020
Priority date	Nov 21, 2013
Publication date	Oct 4, 2022
Grant date	Oct 4, 2022

Abstract

A distance measuring device includes a motor, a control box and a code discs which are relative rotate driven by the motor. A point position tooth is comprised on the code disc. The control box comprises a distance measuring unit, a detection part and a control unit. The detection part comprises a light emitter and a light receiver which are correspondingly arranged. The control box is rotated relative to the code disc, so that the point position tooth passes through a corresponding position between the light emitter and the light receiver; the control unit receives the signal output of the light receiver, judges the information on alignment status of the point position tooth with the corresponding position, and sends a start or stop operation instruction to the distance measuring unit on the basis of the status information. A method for seeking a distance measuring starting point is also provided.

First claim

What is claimed is:

1. A distance measuring device, comprising a motor, a control box and a code disc; wherein,
the control box and the code disc rotate relative to each other under the driving of the motor;
a point position tooth is provided on the code disc;
the control box comprises a distance measuring unit, a detection part and a control unit;
the detection part comprises a light emitter and a light receiver arranged correspondingly;
the point position tooth passes through a corresponding position between the light emitter and the light receiver when the control box and the code disc rotate relative to each other;
the light receiver output a signal whether the point position tooth is aligned to the corresponding position to the control unit; and
the control unit controls the distance measuring unit to operate or not according to the signal.

2. The device according to claim 1 , comprising a base; wherein,
the code disc is fixed on base, a motor pulley is provided at an output end of the motor, and an O-ring is provided on a periphery of the motor pulley and the control box; and a bearing is connected to a central portion of the base, an outer ring of the bearing is fixed to the base and an inner ring of the bearing is fixed to the control box.

3. The device according to claim 1 , wherein, a plurality of equidistant teeth are provided on a circumference of the code disc evenly, and a tooth width of the point position tooth is smaller or larger than that of the equidistant teeth; and the point position tooth and the equidistant teeth pass through the corresponding position when the control box and the code disc rotate relative to each other.

4. The device according to claim 3 , wherein, the code disc comprises one point position tooth and fourteen equidistant teeth, and in clockwise direction, the angle between left edges of two adjacent equidistant teeth is 24°; the angle between left and right edges of the point position tooth is 6°, and the angle between the right edge of the point position tooth and the left edge of an adjacent equidistant teeth on the right side of the point position tooth is 18°; and the angle between the left and right edges of each equidistant tooth is 12°.

5. The device according to claim 3 , wherein, the control unit identifies status information according to the signal, and sends a start operation instruction or a stop operation instruction to the distance measuring unit according to the status information; and wherein, the status information indicates that the point position tooth is aligned to the corresponding position to the control unit.

6. The device according to claim 5 , wherein, the control unit sends the start operation instruction to the distance measuring unit when the status information is identified for a first time, and the control unit sends the stop operation instruction to the distance measuring when the status information is identified for a second time.

7. The device according to claim 6 , wherein, the light receiver outputs waves with square waveforms to the control unit, and the control unit identifies the status information according to levels and widths of the waves.

8. The device according to claim 7 , wherein, the light receiver outputs a wave with a first level and a first width to the control unit when the point position tooth is aligned to the corresponding position, the light receiver outputs a wave with a first level and a second width to the control unit when one of the equidistant teeth is aligned to the corresponding position, otherwise outputs a second level to the control unit; and the control unit identifies the status information according to the wave with the first level and the first width.

9. A method for seeking a distance measuring starting point with the distance measuring device according to claim 3 , comprising:
outputting, by the light receiver, a signal whether the point position tooth is aligned to the corresponding position to the control unit when the control box and the code disc rotate relative to each other, to the control unit; and
controlling, by the control unit, the distance measuring unit to operate or not according to the signal.

10. The method according to claim 9 , the controlling, by the control unit, the distance measuring unit to operate or not according to the signal, comprises:
identifying, by the control unit, status information according to the signal; and
sending, by the control unit, a start operation instruction or a stop operation instruction to the distance measuring unit according to the status information; and wherein, the status information indicates that the point position tooth is aligned to the corresponding position to the control unit.

11. The method according to claim 10 , wherein, the controlling, by the control unit, the distance measuring unit to operate or not according to the signal, comprises:
sending, by the control unit, the start operation instruction to the distance measuring unit when the status information is identified for a first time; and
sending, by the control unit, the stop operation instruction to the distance measuring when the status information is identified for a second time.

12. The method according to claim 11 , wherein, the outputting, by the light receiver, a signal whether the point position tooth is aligned to the corresponding position to the control unit when the control box and the code disc rotate relative to each other, to the control unit, comprises:
outputting, by the light receiver, waves with square waveforms to the control unit;
and wherein, the controlling, by the control unit, the distance measuring unit to operate or not according to the signal, comprises:
identifying, by the control unit, the status information according to levels and widths of the waves.

13. The method according to claim 12 , wherein, the outputting, by the light receiver, a signal whether the point position tooth is aligned to the corresponding position to the control unit when the control box and the code disc rotate relative to each other, to the control unit, comprises:
outputting, by the light receiver outputs, a wave with a first level and a first width to the control unit when the point position tooth is aligned to the corresponding position, or outputting a wave with a first level and a second width to the control unit when one of the equidistant teeth is aligned to the corresponding position, otherwise outputting a second level to the control unit;
and wherein, the controlling, by the control unit, the distance measuring unit to operate or not according to the signal, comprises:
identifying, by the control unit, the status information according to the wave with the first level and the first width.

14. The device according to claim 1 , wherein, the control unit identifies status information according to the signal, sends a start operation instruction to the distance measuring unit when the status information is identified for a first time, and sends a stop operation instruction to the distance measuring when the status information is identified for a second time; and wherein, the status information indicates that the point position tooth is aligned to the corresponding position to the control unit.

15. The device according to claim 14 , wherein, the light receiver outputs waves with square waveforms to the control unit, and the control unit identifies the status information according to levels of the waves.

16. The device according to claim 15 , wherein, the light receiver outputs a first level to the control unit when the point position tooth is alig

Assignees

• Ecovacs Robotics Co Ltd

Inventors

• Tang Jinju

Classifications

• G01D5/3473 Primary

  Circular or rotary encoders · CPC title

• G01C3/08

  Use of electric radiation detectors · CPC title