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US 9,958,329 B2Granted
Photoelectric switch
AssigneeKeyence Corporation
InventorShinichi Tsukigi
Life of this patent
Estimating the term…
Abstract
There is provided a photoelectric switch capable of accurately detecting even such a workpiece where a tint changes within the same workpiece, while preventing erroneous detection. The photoelectric switch includes: a light projecting unit; a light receiving unit; a coincidence degree calculating unit for comparing the acquired color information with a reference color to calculate a coincidence degree of both of the color information. When the color information is newly acquired, a detection signal generating unit compares, with a detection determination threshold, the highest coincidence degree of coincidence degrees calculated by respectively comparing the color information newly acquired, with the two or more reference colors, to perform workpiece determination.
Claims14
A photoelectric switch comprising:
- a light projector configured to project a light toward a detection area;
- a light receiver configured to receive the light from the detection area to generate a plurality of light reception signals respectively corresponding to a plurality of specific wavelengths;
- and
- a controller configured to repeatedly acquire a receiving color based on the plurality of light reception signals respectively corresponding to the plurality of specific wavelengths,
- configured to accept at least one of capture instructions to capture a plurality of reference colors,
- configured to specify the receiving colors acquired in response to the at least one of capture instructions as the plurality of reference colors,
- configured to compare the receiving color repeatedly acquired with each of the plurality of reference colors to calculate a coincidence degree between the receiving color repeatedly acquired and the plurality of reference colors, and
- configured to compare the coincidence degree with a predetermined threshold to generate a detection signal representing a workpiece determination;
- wherein, when the receiving color is newly acquired, the controller compares, with the predetermined threshold, the highest coincidence degree of coincidence degrees calculated by respectively comparing the receiving color newly acquired, with each of the plurality of reference colors, to generate the detection signal.
6 more elements
A photoelectric switch comprising:
- a light projector configured to project a light toward a detection area;
- a light receiver configured to receive the light from the detection area to generate a plurality of light reception signals respectively corresponding to a plurality of specific wavelengths;
- and
- a controller configured to repeatedly acquire a receiving color based on the plurality of light reception signals respectively corresponding to the plurality of specific wavelengths,
- configured to accept at least one of capture instructions to capture a plurality of reference colors including a start reference color, an additional reference color and an interpolated reference color,
- configured to specify the receiving colors acquired in response to the at least one of capture instructions as the start reference color, the additional reference color and the interpolated reference color,
- configured to compare the receiving color repeatedly acquired with each of the plurality of reference colors to calculate a coincidence degree between the receiving color repeatedly acquired and the plurality of reference colors, and
- configured to compare the coincidence degree with a predetermined threshold to generate a detection signal representing a workpiece determination;
- wherein
- the controller specifies the receiving color acquired based on a first one of the capture instructions, as the start reference color, and specifies the receiving color acquired based on a second one of the capture instructions after the first one of the capture instructions, as the additional reference color, and specifies at least one interpolated reference color that interpolate a color between the start reference color and the additional reference color based on the start reference color and the additional reference color,
- when the receiving color is newly acquired, the controller compares the receiving color newly acquired, with the start reference color, the interpolated reference color, and the additional reference color, to respectively calculate the coincidence degrees, and
- the controller compares, with the predetermined threshold, the highest coincidence degree of the coincidence degree with respect to the start reference color, the coincidence degree with respect to the interpolated reference color, and the coincidence degree with respect to the additional reference color, to generate the detection signal.
9 more elements
A photoelectric determination method for generating a detection signal representing a workpiece determination, the method comprising:
- projecting a light toward a detection area;
- receiving the light from the detection area to generate a plurality of light reception signals respectively corresponding to a plurality of specific wavelengths;
- repeatedly acquiring a receiving color based on the plurality of light reception signals respectively corresponding to the plurality of specific wavelengths;
- accepting at least one of capture instructions to capture a plurality of reference colors;
- specifying the receiving colors acquired in response to the at least one of capture instructions as the plurality of reference colors;
- comparing the receiving color repeatedly acquired with each of the plurality of reference colors to calculate the highest coincidence degree of a plurality of coincidence degrees between the receiving color repeatedly acquired and each of the plurality of reference colors;
- and
- comparing the highest coincidence degree with a predetermined threshold to generate a detection signal representing a workpiece determination.
5 more elements
Dependencies are inferred from the claim text.