Light Scanning Photoelectric Switch

• US 20090287453A1
• Filed: 04/21/2009
• Published: 11/19/2009
• Est. Priority Date: 05/14/2008
• Status: Active Grant

• Current Assignee: Keyence Corporation (Keyence)
• Original Assignee: Keyence Corporation (Keyence)
• Inventors: Oh, Choryon
• Granted Patent: US 8,069,007 B2
• Time in Patent Office: Days
• US Class Current: 702/159
• CPC Class Codes: G01B 11/03 by measuring coordinates of points

Abstract

This invention provides a light scanning photoelectric switch with which various settings of the light scanning photoelectric switch such as setting of a protection area can be easily set. The light scanning photoelectric switch includes: a display unit having a display screen that displays information including at least one of a status of a safety function of the light scanning photoelectric switch, and information of a failure status; and an operating unit provided in vicinity of the display unit, and for switching the information displayed in the display screen to different one of the safety signal, the result of the determination, setting contents of the light scanning photoelectric switch, the status of the safety function of the light scanning photoelectric switch, and the information of the failure status.

Claims

1. A light scanning photoelectric switch that outputs a safety signal indicating that an operation of a device connected to the switch is either enabled or disabled, comprising:

a light irradiating unit that applies light along a first axis;

a light scanning unit disposed so as to be angled substantially at 45 degrees to the first axis, the light scanning unit rotating about the first axis, deflecting light applied by the light irradiating unit toward a detection area within a plane perpendicular to the first axis, and deflecting reflected light which is the light reflected on an object within the detection area in a direction along the first axis;

a light receiving lens having a light axis along the first axis, the light receiving lens for collecting the reflected light deflected along the first axis by the light scanning unit;

a light receiving reflecting body disposed so as to be angled substantially at 45 degrees to the first axis, the light receiving reflecting body deflecting the light axis of the reflected light that has been collected by the light receiving lens in a direction substantially perpendicular to the first axis;

a photoelectric transducer that receives the reflected light deflected by the light receiving reflecting body, and photoelectrically converts the received light into a light receiving signal;

a distance calculation unit that calculates a distance to the object based on the light receiving signal from the photoelectric transducer;

a direction calculation unit that calculates a deflect direction of the light deflected toward the detection area by the light scanning unit;

a position recognition unit that recognizes a position of the object based on the deflect direction calculated by the direction calculation unit, and on the distance to the object in the deflect direction calculated by the distance calculation unit;

a failure sensing unit that senses a failure status of the light scanning photoelectric switch;

a determination unit that determines whether or not the object is present within a predetermined protection area based on the position of the object recognized by the position recognition unit, and outputs a safety signal based on a result of the determination, based on the failure status sensed by the failure sensing unit, and on a status of a safety function of the light scanning photoelectric switch;

a display unit disposed substantially parallel to the light receiving reflecting body and angled substantially at 45 degrees to the axis, the display unit having a display screen that displays information including at least one of the safety signal, the result of the determination, setting contents of the light scanning photoelectric switch, the status of the safety function of the light scanning photoelectric switch, and information of the failure status; and

an operating unit provided in vicinity of the display unit, and for switching the information displayed in the display screen to different one of the safety signal, the result of the determination, the setting contents of the light scanning photoelectric switch, the status of the safety function of the light scanning photoelectric switch, and the information of the failure status.

2. The light scanning photoelectric switch according to claim 1, wherein

the detection area includes at least a front area and both side areas of the light scanning photoelectric switch, and the photoelectric transducer is disposed at a rear side of the light scanning photoelectric switch.

3. The light scanning photoelectric switch according to claim 1, wherein

as the setting contents that are displayed in the display screen, three directions from a reference point of the protection area and distances in the three directions from the reference point are displayed.

4. The light scanning photoelectric switch according to claim 1, further comprising:

an indicating lamp for an OSSD that indicates the result of the determination on whether or not the object is present within the protection area; and

an indicating lamp for an interlock status in which, when the object is present within the protection area, an operation is disabled until a predetermined input for resetting is inputted, wherein

the indicating lamp is provided in vicinity of the display screen of the display unit.

5. The light scanning photoelectric switch according to claim 1, wherein

the operating unit further includes an operation button for setting the setting contents, and the operation button is provided on a surface on which the display screen is provided.

6. The light scanning photoelectric switch according to claim 1, further comprising:

a light projecting device that projects the light along a line formed by having a normal line that passes through the light axis of the light receiving lens and that is perpendicular to the rear side rotate about the light axis by an angle substantially at 40 to 50 degrees.