Patent ID: 6774357
Filing Date: 2004-08-10
Classification: G01S,G01V,H03K

Abstract:
A photoelectric switch device for detecting a presence or an absence of an object in a specified field of detection, which has at least a light projecting means including a light emitting means and an optical means for projecting light forward to the field of detection, light receiving means including photoelectric element and optical means for receiving light from the field of detection and generating an electric signal of a level representing an amount of light incident thereupon and processing means for processing the electric signal from said photoelectric means, for making a determination of the presence or the absence of the object in the field of detection on the basis of a comparison of the level of the electric signal from said photoelectric means with a specified threshold and for providing an electric signal representing a result of the determination, all of said means being installed in a generally rectangular-parallelepiped box casing defined by a plurality of walls, said photoelectric switch device comprising:a transparent window panel disposed in a rear wall of said generally rectangular-parallelepiped box casing; a display board disposed behind said transparent window panel within said generally rectangular-parallelepiped box casing; display means disposed on said display board and operatively connected to said processing means for providing a numerical display of the specified threshold of the electric signal from said photoelectric means; adjusting switch means disposed on said display board and operatively connected to said processing means for adjusting said numerical display of the specified threshold when operated; manually operable switch means disposed on said rear wall for operating said adjusting switch; a first circuit board provided with a power supply circuit printed thereon through which electric power is supplied to the photoelectric switch device and disposed in said generally rectangular-parallelepiped box casing behind said display board in close proximity to and in parallel with either one of opposite side walls of said generally rectangular-parallelepiped box; and a second circuit board provided with an excitation circuit printed thereon and operationally connected to said processing means for exciting said light emitting means for emitting light and disposed behind said display board within said generally rectangular-parallelepiped box casing in close proximity to and in parallel with another one of said side walls of said generally rectangular-parallelepiped box.