JP2015165520A - photoelectric switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal photoelectric switch which is provided with relatively large display means capable of displaying an amount of light received and a distance thereby improving the convenience of the photoelectric switch and minimizes enlargement of the photoelectric switch which is caused by the display means.SOLUTION: A photoelectric switch includes a display window 6 formed on a wall arranged perpendicular to another wall on which a one-side opening 30 of a metal housing is provided. A detection value displayed by a display member 36 is displayed through the display window 6. The display window 6 has a step part forming an opening peripheral part. A display cover 40 is fixed to the step part. The display cover 40 and the display member 36 are positioned in the display window 6.

Description

  The present invention relates to a photoelectric switch having a metal casing.

  Photoelectric switches have a function of detecting the presence or absence of an object by projecting and receiving light and are used in a wide range of fields. As seen in Patent Documents 1 to 4, the photoelectric switch is miniaturized and highly functionalized, and a resin molded product that is convenient for forming a complicated shape for accurately mounting the built-in components is adopted. The outer shape is made of molded products.

  When using a photoelectric switch in a harsh usage environment for a resin molded product, measures are taken to surround the photoelectric switch with a dedicated metal cover. Patent Document 5 proposes a photoelectric switch that can meet demands such as chemical resistance, oil resistance, and robustness. This photoelectric switch has a metal casing, and a built-in component is accommodated in the metal casing. Specifically, Patent Document 5 makes a metal (stainless steel) housing in which a peripheral wall and one side wall are integrally formed by a metal injection mold, and a built-in component is opened from an opening opened on one side. A photoelectric switch is disclosed in which a lid plate constituting the other side wall is bonded to the peripheral edge of the opening of the housing after being filled in.

  By manufacturing the case by the metal injection molding method, the wall of the metal case can be made relatively thin, thereby reducing the size of the photoelectric switch provided with the metal case, that is, the synthetic resin photoelectric switch. A small metal photoelectric switch corresponding to the above can be provided.

JP 2001-194140 A JP 2001-202859 A JP 2001-211062 A JP 2001-210202 A JP 2007-73417 A

  The synthetic resin photoelectric switch has a relatively large display window, and the amount of received light and the distance are displayed on the display window. When this display means is applied to a photoelectric switch having a metal casing, the metal photoelectric switch is increased in size.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a photoelectric switch that can be provided with a relatively large display means capable of displaying the amount of received light and the distance to increase the convenience of the metal photoelectric switch and suppress the increase in size associated with it. is there.

According to the present invention, the above technical problem is
A light projecting element that projects light toward the detection area;
A light receiving element that receives light from the light projecting element reflected by the detection region and outputs a signal corresponding to the received light;
A control unit that calculates a detection value corresponding to an amount of light received or a distance based on the signal from the light receiving element, and outputs a detection output based on the calculated detection value and a predetermined threshold;
An output indicator lamp for displaying according to the detection output;
A display member for displaying the detected value;
A metal housing that houses the light projecting element, the light receiving element, the control unit, and the display member;
A metal plate member for closing one side opening formed on one side wall of the walls of the metal housing;
A display window for displaying the detection value formed on the other wall of the housing orthogonal to the one side wall provided with the one side opening and displayed by the display member;
A step portion constituting an opening peripheral edge portion of the display window;
A display cover fixed to the stepped portion and covering the display window;
This is achieved by providing a photoelectric switch in which the display cover and the display member are located in the display window.

  According to the present invention, by positioning the display cover and the display member in the display window, it is possible to reduce the size and improve the visibility of the display member.

  Further operational effects, other objects and operational effects of the present invention will become apparent from the following detailed description of preferred embodiments of the present invention.

It is the perspective view which looked at the photoelectric switch of 1st Example from diagonally forward. It is the perspective view which looked at the photoelectric switch of 1st Example from diagonally backward. It is a side view of the photoelectric switch of 1st Example. It is the disassembled perspective view which looked at the photoelectric switch of 1st Example from diagonally backward. It is the disassembled perspective view which looked at the photoelectric switch of 1st Example from diagonally forward. It is the disassembled perspective view which looked at the built-in component group of the photoelectric switch of 1st Example from diagonally backward. It is the disassembled perspective view which looked at the built-in components group of the photoelectric switch of 1st Example from diagonally forward. It is a cross-sectional view of the photoelectric switch cut along the line VIII-VIII in FIG. It is a longitudinal cross-sectional view of the photoelectric switch of 1st Example. FIG. 10 is an enlarged cross-sectional view of a portion indicated by an arrow X10 in FIG. FIG. 10 is an enlarged cross-sectional view of a portion indicated by an arrow X11 in FIG. FIG. 10 is a longitudinal cross-sectional view corresponding to FIG. 9, and is a diagram illustrating a control board, an optical system module, operation buttons, and related members, cables, and related members omitted. It is a top view of the photoelectric switch of 1st Example, Comprising: It is the figure which excluded the light-diffusion component of the output indicator lamp, and the output indicator lamp cover. It is a top view of the photoelectric switch corresponding to FIG. 13, Comprising: It is the figure which abbreviate | omitted the output indicator lamp cover of the output indicator lamp. It is a block diagram of the photoelectric switch of 1st Example. It is a figure for demonstrating operation | movement of the photoelectric switch of 1st Example. It is a figure for demonstrating operation of the photoelectric switch of 1st Example, Comprising: It is a rear view of a photoelectric switch. It is a figure for demonstrating operation of two-point tuning of the photoelectric switch of 1st Example. It is a figure for demonstrating operation of datum tuning of the photoelectric switch of 1st Example. It is a figure for demonstrating operation of the maximum sensitivity tuning of the photoelectric switch of 1st Example. It is a figure for demonstrating operation of the full auto tuning of the photoelectric switch of 1st Example. It is a figure for demonstrating operation which switches the display of the 7 segment display window of the photoelectric switch of 1st Example from a distance display to a threshold value display. It is a figure for demonstrating the output change operation of the photoelectric switch of 1st Example, and the change of the display of a 7 segment display window accompanying this. It is a figure for demonstrating the transition of the display in the operation mode of the photoelectric switch of 1st Example. It is a figure for demonstrating the transition of the display in the operation mode following FIG. It is a figure for demonstrating the switching setting of a peak hold and a bottom hold. It is a figure for demonstrating the shift function of the photoelectric switch of 1st Example. It is a figure for demonstrating the clamp function of the photoelectric switch of 1st Example. It is the perspective view which looked at the photoelectric switch of 2nd Example from diagonally forward. It is the perspective view which looked at the photoelectric switch of 2nd Example from diagonally backward. It is a side view of the photoelectric switch of 2nd Example. It is the perspective view which looked at the photoelectric switch of 2nd Example from diagonally forward and diagonally upward, and is the figure which removed and illustrated the cover plate from the housing | casing. It is the figure which looked at the photoelectric switch of 2nd Example from the front. It is the disassembled perspective view which looked at the photoelectric switch of 2nd Example from diagonally forward. It is a top view of the photoelectric switch of 2nd Example. It is a cross-sectional view of the photoelectric switch of the second embodiment. FIG. 37 is an enlarged partial cross-sectional view of a portion indicated by X37 in FIG. 36. It is the perspective view which looked at the photoelectric switch of 2nd Example from diagonally forward and diagonally downward, and is the figure which removed and showed the cover plate from the housing | casing. It is a longitudinal cross-sectional view of the photoelectric switch of 2nd Example. It is a cross-sectional view of the top of the photoelectric switch of the second embodiment. It is a block diagram of the photoelectric switch of 2nd Example.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

First Example (FIGS. 1 to 12) :
The photoelectric switch of the first embodiment has external dimensions of 43 mm in length, 28 mm in width, and 14 mm in depth, and includes a stainless steel casing manufactured by a metal injection molding method. The photoelectric switch of the first embodiment employs a CMOS sensor as a light receiving element, the object detection principle is distance, and the object detection is output as an ON / OFF signal. In addition, the photoelectric switch of the first embodiment has a relatively large output indicator lamp, and includes a 7-segment display that displays a distance or a threshold value by selective switching. Also, there are a plurality of buttons operated by the user, and the operation mode, teaching mode, and operation setting mode can be switched by operating these buttons. And sensitivity can be adjusted by button operation. It is also possible to perform so-called rewriting during RUN (rewriting during operation) in which the setting value is changed while executing the detection operation during the teaching mode and the operation setting mode.

  1-3 is a figure which shows the external appearance of the photoelectric switch 100 of 1st Example. FIG. 1 is a view of a photoelectric switch 100 provided with a light projecting / receiving window as viewed obliquely from the front, FIG. 2 is a view of a rear surface provided with a 7-segment display window as viewed from an oblique rear, and FIG. It is a side view.

  1 to 3, the photoelectric switch 100 has an outer contour formed of a stainless steel housing 2 and a stainless steel flat lid plate 4 (FIG. 3) bonded to one side thereof. . The housing 2 is manufactured by a metal injection molding method. The lid plate 4 is manufactured by cutting out a flat plate. The housing 2 has a shape in which one of the four corners of the rectangle in side view is obliquely cut, and a 7-segment display window 6 is provided on the side where the diagonally cut corner is located. (FIG. 2), and a light projecting / receiving window 8 is provided on the opposite side (FIG. 1). Hereinafter, the side on which the light projecting / receiving window 8 is provided is referred to as the front surface, and the side on which the 7-segment display window 6 is provided is referred to as the back surface.

  As shown in FIGS. 1 to 3, the photoelectric switch 100 is provided with switch installation holes SH at the upper end portion and the lower end portion of the front portion, respectively, and bolts (not shown) inserted through the switch installation holes SH. The photoelectric switch 100 is installed at a desired position by using.

  A cable 12 is positioned at the corner 10 having an obliquely cut shape (FIGS. 2 and 3). The power supply to the photoelectric switch 100 and the detection signal from the photoelectric switch 100 to an external device, that is, the detection signal, that is, An ON / OFF signal is output. An output indicator lamp 16 (FIGS. 1 and 3) is disposed at a corner portion 14 diagonally opposed to the corner portion 10 diagonally cut out where the cable 12 is located. When the corner 10 where the cable 12 extends is called the “lower surface” and the corner 14 side where the output indicator 16 is located is called the “upper surface”, the cable 12 is oblique to the photoelectric switch 100. It is disposed at the inclined lower back corner. The above-described output indicator lamp 16 is disposed at the upper front corner of the photoelectric switch 100, and the output indicator lamp 16 extends from the front end portion of the upper surface to the upper end of the front surface, as can be seen from FIGS. Moreover, it has the shape which protruded from the front surface and upper surface of the housing | casing 2. As shown in FIG.

  The photoelectric switch 100 also has an UP button 18 and a DOWN button 20 up and down across the 7-segment display window 6 on the back side, and the user looks at the display of the 7-segment display window 6 and the UP button 18 or DOWN button. The threshold value can be adjusted by depressing 20. The photoelectric switch 100 also has a SET button 22 on its upper surface, and threshold tuning can be performed by a pressing operation of the SET button 22, that is, a push operation (tuning mode). Different tunings can be performed with long and short combinations.

  4 and 5 are exploded views of the photoelectric switch 100, FIG. 4 is a perspective view seen from the back side, and FIG. 5 is a perspective view seen from the front side. As best seen from FIG. 4, the housing 2 has a peripheral wall 26 and has a box shape with one side wall and the other side open, and the above-described 7-segment display is provided on the peripheral wall 26. A window 6 and a light projection window 8 are formed, and a total of three through holes 24 in which the UP button 18, the DOWN button 20, and the SET button 22 are installed are formed. A side opening of the box-shaped housing 26 is indicated by reference numeral 30.

  Referring to FIGS. 4 and 5, reference numeral 32 denotes a group of built-in components that are filled in the housing. Although the built-in component group 32 will be described in detail later, the built-in component group 32 is fastened to the side wall 28 (FIG. 5) constituting a part of the housing 2 using two screws S1.

  From the outside, the casing 2 has a lens cover 34, a 7-segment display part 36, a light diffusion sheet 38, and a 7-segment display of the light-transmitting resin molded product, which are members related to light projection and reception. A cover 40, a light diffusing component 42 constituting a part of the output indicator lamp 16, and an output indicator lamp cover 44 of a resin molded product having a shape protruding outward are attached. Specifically, the 7-segment display component 36 is also called a reflector and substantially defines the shape of each segment, and is made of a plate-like insulating material in which an opening corresponding to the shape of each segment is formed. In the member, the inner wall of the aperture is made of white or a highly reflective material such as metallic luster. The light emitted from the 7-segment display LED group 70 (FIG. 6) of the distance display / control board 52 described later is reflected by the inner wall of the hole corresponding to the shape of each segment of the 7-segment display component 36, and each segment is reflected. It can be displayed evenly. The lens cover 34 of a resin molded product is bonded to a step portion constituting the peripheral portion of the light projecting / receiving window 8 of the housing 2, and the lens cover 34 seals the light projecting / receiving window 8 by this adhesion. Further, the 7-segment display cover 40 of the light-transmitting resin molded product is bonded to a step portion constituting the peripheral portion of the 7-segment display window 6 of the housing 2, and the 7-segment display cover 40 is bonded to the 7-segment display window 6 by this bonding. To seal. With respect to the creeping distance related to the light projecting / receiving window 8 and the 7 segment display window 6, a lens cover is formed on the outer surface of the housing 2 by forming a step at the peripheral edge of the light projecting / receiving window 8 and the 7 segment display window 6. Not only can the 34 and 7 segment display covers 40 be flush with each other, it is also easy to ensure a creepage distance by the stepped portions at the peripheral portions of the light projecting / receiving windows 8 and the 7 segment display windows 6.

  6 and 7 are exploded views of the built-in component group 32, FIG. 6 is a perspective view seen from the 7-segment display side, and FIG. 7 is a perspective view seen from the light projecting / receiving side. Referring to FIGS. 6 and 7, reference numeral 50 denotes a light projecting / receiving substrate, and reference numeral 52 denotes a distance display / control board. The light emitting / receiving substrate 50 has a three-dimensional structure in which a part of a flexible substrate is reinforced with a board, and two output display LEDs 54 and 56 having different colors are arranged side by side on the top surface, that is, aligned in the width direction of the photoelectric switch 100. In addition, an electronic component switch 58 related to the SET button 22 is positioned adjacent thereto.

  With continued reference to FIGS. 6 and 7, reference numeral 60 denotes an optical system module. The optical system module 60 includes a light receiving element 62 (FIG. 6), a light receiving lens 64 (FIG. 7) positioned corresponding to the light receiving element 62, and a laser diode (light projecting element) 66 (FIG. 6). The optical system module 60 is made by assembling the above to a resin molding frame. The light receiving element 62 is fixed by adhering it to a resin molding frame. The terminal 66 a of the laser diode 66 is soldered to the light projecting / receiving substrate 50.

  Referring to FIG. 6, a connector 68 is fixed to the three-dimensional light projecting / receiving substrate 50, and a distance display / control board 52 is fitted to the connector 68 to connect the distance display / control board 52 to the light projecting / receiving board. 50. Reference numeral 69 in FIG. 7 denotes a connector of the distance display / control board 52. The distance display and control board 52 has a 7-segment display LED group 70 (FIG. 6) and electronic component switches 72 and 74 disposed above and below the 7-segment display LED group 70. The upper electronic component switch 72 is a switch corresponding to the UP button 18 (FIG. 2), and the lower electronic component switch 74 is a switch corresponding to the DOWN button 20 (FIG. 2).

  The code | symbol 76 seen in FIG. 6, FIG. 7 shows an insulating sheet, and the code | symbol 78 shows a thermal radiation rubber | gum. The heat radiation rubber 78 is used to transmit heat generated by the laser diode 66 to the metal housing 2.

  On the distance display / control board 52, a light shielding rubber 80 as a light shielding member is attached to the 7-segment display LED group 70, and a positioning through hole 80a is formed in the light shielding rubber 80. The light shielding rubber 80 is fixed in position by a distance display resin molding frame 82. This resin-molded frame 82 has a positioning pin 82a (FIG. 7) integrally molded, and this positioning pin 82a passes through the positioning through hole 80a of the light shielding rubber 80, and the recess 52a (FIG. 6), the relative positioning between the light shielding rubber 80 and the 7-segment display LED group 70 is performed. The resin molding frame 82 also has an outer contour complementary to the distance display / control board 52, and a locking claw 82 b that engages with the peripheral edge of the distance display / control board 52 at the periphery of the resin molding frame 82. Are formed, and the resin-molded frame 82 can be positioned with respect to the distance display / control board 52 by snap-fitting the locking claws 82b to the peripheral edge of the distance display / control board 52.

  As best seen from FIG. 6, the resin-molded frame 82 has two elongated positioning protrusions 82d extending in the lateral direction spaced apart from each other in the vertical direction, and a groove (not shown) for receiving the positioning protrusions 82d is formed in the housing. The resin molding frame 82 is positioned with respect to the housing 2 by the positioning projections 82d.

  The zenith portion of the group of built-in components 32 sub-assembled in advance is a third LED disposed on the electronic component switch 58 corresponding to the two LEDs 54 and 56 and the SET button 22 constituting a part of the output indicator lamp 16. The resin molding frame (resin molding frame for output display) 90 is configured. The output display resin molding frame 90 has two positioning pins 90c extending downward, in addition to the LED window 90a and the opening 90b for the SET button 22. The two positioning pins 90c extend toward the top of the light projecting / receiving substrate 50. Two positioning holes 50a are formed at the top of the light projecting / receiving substrate 50 with the electronic component switch 58 interposed therebetween. The resin molding frame 90 for output display is positioned with respect to the light projecting / receiving substrate 50 by inserting the two positioning pins 90c into the positioning holes 50a and thermally crimping the tip portions of the positioning pins 90c. The output display resin molding frame 90 also has two positioning protrusions 90d protruding upward (FIG. 6), and a recess having a complementary shape corresponding to the positioning protrusion 90d and receiving it is provided. Formed on the inner wall of the metal casing 2, the output display resin molding frame 90 is positioned with respect to the casing 2.

  With further reference to FIGS. 6 and 7, the above-mentioned resin molded frame for output display 90 constituting the zenith portion of the built-in component group 32 includes a first extending in the width direction of the housing 2 on the 7-segment distance display side. A spring piece 92 is integrally formed. As will be described in detail later, the first spring piece 92 works in the front-rear direction of the housing 2 to urge the group of built-in components 32 toward the front side of the photoelectric switch 100 and to display the distance display / control board 52. Is urged toward the back side of the photoelectric switch 100.

  With reference to FIG. 8, in the assembly process of the photoelectric switch 100, the built-in component group 32 is filled into the metal casing 2 through the side opening 30 of the metal casing 2. That is, the built-in component group 32 is accommodated in the housing 2 through the side opening 30 as a pre-assembled assembly. The width of the built-in component group 32 is indicated by BW in FIG. On the other hand, the width of the side opening 30 is indicated by Ow. As can be seen from FIG. 8, the width BW of the built-in component group 32 is smaller than the width Ow of the side opening 30 (Bw <Ow). After the built-in component group 32 is accommodated in the housing 2, a 7-segment display component 36 is inserted from the outside into the 7-segment display window 6 as an additional component related to the 7-segment distance display, and thereafter, the light diffusion sheet 38. Then, a 7-segment display cover 40, which is a resin molded product, is bonded to the stepped portion constituting the opening peripheral edge of the 7-segment display window 6. At the time of this bonding, the opening corresponding to each segment formed in the 7-segment display component 36 and the opening corresponding to each segment formed in the light shielding rubber 80 are coincident with each other. The component 36 is attached to the distance display / control board 52 in a state where the light shielding rubber 80 is compressed, and is held by the repulsive force. The 7-segment display component 36 preferably has a shape whose outer contour is complementary to the 7-segment display window 6 of the housing, whereby all or a part of the 7-segment display member 36 is replaced with the 7-segment display window of the housing. The 7-segment display component 36 may be positioned by the 7-segment display window 6 by being positioned at the portion 6.

  In the photoelectric switch 100 according to the embodiment, as shown in FIG. 4, the 7-segment display unit 36 has a plurality of positioning pins 36 a, and on the other hand, a distance display that faces the 7-segment display unit 36. A plurality of positioning holes 82c for receiving the positioning pins 36a are formed in the resin molding frame 82, and the 7-segment display portion 36 is interposed through the distance display resin molding frame 82 by the positioning pins 36a and the positioning holes 82c. Are positioned on the housing 2.

  The 7-segment display component 36 disposed from the outside has a width dimension indicated by La in FIG. 8. When the 7-segment display component 36 is sub-assembled into the built-in component group 32, the width BW of the built-in component group 32 is obtained. And the width La of the 7-segment display component 36 is a value that exceeds the value of the width OW of the side opening 30 of the metal casing 2 and is incorporated into the casing 2 through the side opening 30. I can't do that. In other words, when the housing 2 is filled in the built-in component group 32 with the 7-segment display component 36 sub-assembled, the housing 2 is filled through the side opening 30. Therefore, it is necessary to set the width dimension of the housing 2 to be larger than that of the first embodiment. As a result, the width dimension of the photoelectric switch 100 is enlarged and the photoelectric switch 100 is enlarged.

  By separating the 7-segment display component 36 from the built-in component group 32 as in the first embodiment, the width dimension of the metal housing 2 can be set to a relatively small value, and the display of 7 segments and the like is possible. Miniaturization of the photoelectric switch 100 including the unit can be realized. Looking at the photoelectric switch 100 according to the embodiment from another viewpoint, the photoelectric switch 100 according to the first embodiment employs an optical system including a relatively large light receiving lens 64, but has 7 segments at a position opposed to this. When a relatively large distance display unit such as is arranged, the width of the housing 2 must be set large. That is, there arises a problem that a relatively small optical system must be employed to avoid the increase in size of the photoelectric switch 100. On the other hand, in the photoelectric switch 100 of the first embodiment, the 7-segment display component 36 is separated from the built-in component group 32 and the 7-segment display component 36 that is a constituent element of the distance display member is assembled from the outside of the housing 2. Thus, it is possible to achieve downsizing of the photoelectric switch 100 in which the optical system and the distance display unit are arranged at positions facing each other in the width direction and the metal casing 2 is provided.

  Further, by adopting a method in which the 7-segment display cover 40 and the lens cover 34 are directly bonded to the housing 2, a width for installing another member for ensuring a waterproof function, for example, a packing member is required. It can be reduced by that amount.

  9 to 11 are views showing a longitudinal section of the photoelectric switch 100, FIG. 9 is a longitudinal sectional view of the photoelectric switch 100, FIG. 10 is a partial sectional view indicated by X10 in FIG. 9, and FIG. It is a fragmentary sectional view shown by. As will be readily understood with reference to FIGS. 9 to 11, the three buttons on the peripheral wall 26 of the housing 2, that is, the periphery of the UP button 18, the DOWN button 20, and the SET button 22, indicate the stability of these buttons 18, 20, 22. In order to ensure the stability of the general push-down stroke and return stroke, it is designed to be relatively thicker than other parts. By arranging the 7-segment display window 6 at a position between the UP and DOWN buttons 18 and 20, the portion of the 7-segment display window 6 is also relatively thick. By using the relatively large wall thickness of the peripheral wall 26, the above-mentioned 7-segment display component 36 can be stably accommodated in the 7-segment display window 6 for the first time. In other words, the method of separating the 7-segment display component 36 from the built-in component group 32 and assembling the 7-segment display component 36, which is a constituent element of the distance display member, from the outside of the housing 2 is relatively easy. It can be said that this is a technique that can be adopted by having a large thickness.

  The UP button 18, the DOWN button 20, and the SET button 22 have a common mounting structure, and circumferential grooves 18 a, 20 a, and 22 a are formed in a part of the buttons 18, 20, and 22. The circumferential grooves 18 a, 20 a, By providing a seal ring 96 in contact with the wall surface of the through hole 24 at 22a, the waterproofness of the through hole 24 for assembling the UP button 18, the DOWN button 20, and the SET button 22 is secured.

  Regarding the cable 12 extending from the photoelectric switch 100, the cable 12 is fixed inside the photoelectric switch 100 by a cable fixing frame 98 (FIGS. 4 and 5) which is a resin molded product. The cable fixing frame 98 is fixed to the integrally formed side wall 28 of the housing 2 by the second screw S2. As best seen in FIG. 4, the cable fixing frame 98 includes a second spring piece 102 extending in the width direction of the housing 2, and the biasing force of the second spring piece 102 is the front-rear direction of the housing 2. To work. That is, the second spring piece 102 of the cable fixing frame 98 abuts on the front surface of the distance display / control board 52, that is, the surface on the deep side of the housing 2. The lower end portion is urged toward the back surface of the photoelectric switch 100.

  FIG. 12 is a diagram in which the illustration of the built-in component group 32 of the photoelectric switch 100 is omitted. Referring to FIG. 12, a third resin molding frame (resin molding frame for output display) 90 is positioned at the upper end of photoelectric switch 100, and a cable fixing frame 98 is positioned at the lower end. The resin display frame 90 for output display is positioned with respect to the housing 2 by engaging and recessing 104 with the first screw S1 and the inner surface of the housing 2. On the other hand, the cable fixing frame 98 is positioned with respect to the housing 2 by the second screw S2 as described above.

  The resin display frame 90 for output display and the cable fixing frame 98 positioned above have spring pieces 92 and 102, respectively. When the spring piece 92 of the resin display frame 90 for output display is called an upper spring piece and the spring piece 102 of the cable fixing frame 98 is called a lower spring piece, the upper spring piece 92 and the lower spring piece 102 are respectively displayed as distances. The both ends of the cum control board 52 on the front side, that is, the upper end and the lower end on the optical system side are brought into contact with each other, so that the distance display / control board 52 faces the inner surface on the back side of the peripheral wall 26 of the housing 2. Energized. When the housing 2 is filled with the built-in component group 32, the built-in component group 32 is displaced to the front side by the reaction force from the distance display / control board 52 by the upper spring piece 92 and the lower spring piece 102, and the first screw By fixing the built-in component group 32 to the housing 2 in S1, the built-in component group 32 is positioned at a predetermined position. The built-in component group 32 is sealed by bonding the flat lid plate 4 to the housing 2. Reference numeral 106 shown in FIG. 5 indicates a heat dissipation sheet. When it is necessary to improve the heat dissipation of the photoelectric switch 100, it is preferable to attach the heat dissipation sheet 106 to the inner surface of the lid plate 4 as shown in FIG.

  The output indicator lamp 16 of the photoelectric switch 100 will be described with reference to FIGS. 10 and 12. The LEDs 54 and 56, which are light sources for output display, are arranged inside the housing 2, and the lights of the LEDs 54 and 56 are It is discharged to the outside through the light diffusion component 42 of a resin molded product. As can be clearly understood from FIGS. 4 and 13, the light diffusing component 42 is disposed in a recess 108 formed at the upper front corner of the housing 2. FIG. 13 is a plan view of the photoelectric switch 100 with the light diffusion component 42 and the output indicator lamp cover 44 removed. FIG. 14 is a plan view of the photoelectric switch 100 with the output indicator light cover 44 removed. As can be seen from FIG. 14, the light diffusing component 42 has a relatively large shape extending to the vicinity of the front surface, and the entire light diffusing component 42 shines. The output indicator lamp cover 44 that is larger than the light diffusing component 42 extends from the upper surface of the housing 2 to the upper end of the front surface and has a shape protruding outward. The light emitted by the light diffusing component 42 substantially becomes a surface light source, and the surface light source produced by the light diffusing component 42 is widely diffused including the reflection on the metal surface of the housing 2, and the output indicator lamp cover. It will be discharged to the outside from all 44 areas. Therefore, the output state of the photoelectric switch 100 can be visually recognized from the front, upper, side, and rear. Further, the light diffusion component 42 made of this resin molded product can also serve as an insulation between the substrates of the output display LEDs 54 and 56 and the metal housing 2.

  As described at the beginning, the photoelectric switch 100 has switch installation holes SH formed at the upper end and lower end of the front portion thereof, and as best seen from FIG. 12, the periphery of the switch installation hole SH of the housing 2 is formed. Is designed to be thick so as to ensure the installation rigidity of the photoelectric switch 100 (prevention of mounting play).

  As described above, the output display LEDs 54 and 56 are installed in the upper corner of the front surface of the photoelectric switch 100. However, because of the presence of the switch installation hole SH, the output display LEDs 54 and 56 are arranged on the rear side of the upper switch installation hole SH. Displaced and output display LEDs 54 and 56 are installed. In order to solve the problem that the output display LEDs 54 and 56 have to be displaced on the back side in this way, the light diffusing component 42 described above is prepared in the photoelectric switch 100 of the first embodiment. By designing the part 42 into a shape that is enlarged in the front-rear direction, the light emitted from the output display LEDs 54, 56 can be sent to the upper area of the upper switch installation hole SH and can be made as a uniform surface light source as much as possible. It is designed to ensure visibility from a wide range by an output indicator lamp cover 44 that is expanded in front of the light diffusing component 42 as the surface light source and up to the front surface of the photoelectric switch 100.

  Two LEDs 54 and 56 are arranged side by side as a light source for output display. By these two LEDs 54 and 56, display linked with the ON / OFF output signal of the photoelectric switch is performed. Different display contents may be assigned to the two LEDs, for example, to display in conjunction with two ON / OFF output signals corresponding to different threshold values, or the emission colors of the respective LEDs may be different. It may be. For example, the ON / OFF output display of the photoelectric switch is assigned to the LED 54, the emission color is set to red, and the stable operation display indicating whether the photoelectric switch can stably detect the detection target is assigned to the LED 56, and the emission color is set. May be green. When assigning different display contents to the LEDs 54 and 56, a light diffusing member corresponding to each of the LEDs 54 and 56 is provided, and a light shielding member is interposed between the light diffusing members, so that the colors of the LEDs 54 and 56 are mixed or color leakage is caused. Is prevented. On the other hand, the photoelectric switch 100 of the first embodiment is capable of displaying the detection value and the like corresponding to the stable operation display by the large 7-segment display window 6 provided on the back surface for displaying the detection value and the like. , 56 are assigned to display in conjunction with the ON / OFF output signal of the photoelectric switch. In this case, since the LEDs 54 and 56 can be handled as an integrated light source and no light shielding member is required, the light shielding member can also be used as a light diffusion member, and the display area of the output display is large in the width direction. Can be

  FIG. 15 is a block diagram of the photoelectric switch 100 of the first embodiment. The photoelectric switch 100 outputs a detection signal corresponding to the distance to the detection object (work) W detected using the laser light, and the detection output is ON / OFF as described above. More specifically, the light from the laser according to the laser drive circuit is projected toward the detection area, and the reflected light from the detection target W in the detection area is received by the one-dimensional CMOS sensor (light receiving element 62). The light reception signal is sent to the control circuit as a light reception waveform indicating the light quantity distribution on the one-dimensional CMOS sensor, and the light reception position of the reflected light on the one-dimensional CMOS sensor is specified based on the light reception waveform, and the distance from the light reception position is determined. Is calculated. A detection signal is output by comparing the calculated distance with a predetermined threshold value. The threshold value can be adjusted, and after pressing the SET button 22 to switch to the teaching mode, the threshold value is based on the actual detection value (distance) detected by operating in the teaching mode as shown in FIG. As shown in FIG. 17, the threshold value can be finely adjusted by operating the UP button 18 and the DOWN button 20 while viewing the numerical display of the 7-segment display window 6. it can. The output indicator lamp 16 is turned on or off in conjunction with the detection output (ON / OFF output) of the photoelectric switch 100.

  The teaching mode includes (1) two-point tuning (FIG. 18), (2) datum tuning (FIG. 19), (3) maximum sensitivity tuning (FIG. 20), and (4) full auto tuning (FIG. 21). .

Two-point tuning (Figure 18) :
This tuning method is the most standard threshold setting method. More specifically, the detection value (distance) when there is a detection target and the detection value (distance) when there is no detection target are captured according to the operation timing of the user of the SET button 22 (teaching button), and the detection target This is a method of setting a value between a detection value (distance) in a state where there is a detection value and a detection value (distance) in a state where there is no detection target as a threshold value (setting value). Typically, an intermediate value between the detection value (distance) when there is a detection target and the detection value (distance) when there is no detection target is set as the threshold value (setting value).

  The photoelectric switch 100 according to the first embodiment is configured such that different teaching methods are executed by a combination of short pressing (for example, 1 second or less) and long pressing (for example, 3 seconds or more) of the SET button (teaching switch button) 22. Has been. When performing two-point tuning, press the SET button 22 for a short time with a detection target, and press the SET button 22 for a short time with a detection value (distance) with no detection target. The detection value (distance) is captured according to the operation timing of 22.

  When the control circuit determines that the difference between the detection value (distance) when the detection target is present and the detection value (distance) when there is no detection target is sufficiently stable to be detected In the 7 segment display window 6, an intermediate value between a detection value (distance) in a state where a detection target is present and a detection value (distance) in a state where there is no detection target is set as a threshold value (set value). The threshold set by this teaching is displayed on the (display section), and after a certain time has elapsed (for example, after 3 seconds have elapsed), the detected value (distance) is again displayed on the 7-segment display window 6 (display section). Is displayed. After the threshold is set, a detection operation is performed according to the set threshold.

  If the control circuit determines that the difference between the detection value (distance) when there is a detection target and the detection value (distance) when there is no detection target is not enough to be detected stably, The threshold value is not set, the value before teaching operation is maintained as it is, and an indication that the threshold value could not be set on the 7-segment display window 6 (display section), for example, “----” or the like Is displayed, and after a predetermined time has elapsed (for example, after 3 seconds have elapsed), the detected value (distance) is displayed again on the 7-segment display window 6 (display unit).

  The detection value (distance) after execution of the two-point tuning is a value such that the value far from the photoelectric switch 100 among the detection values (distance) acquired when the two-point tuning is executed is “0 (zero)”. Are shifted, and the shifted detection value (distance) is displayed in the 7-segment display window 6. Further, the detection value (distance) is displayed so that the detection value (distance) increases as the distance from the photoelectric switch 100 increases. By displaying in this way, when there is only a background object in the detection target region, the detection value (distance) is displayed as “0 (zero)” in the 7-segment display window 6, while When there is a detection target in the target area, a value corresponding to the height (thickness) of the detection target will be displayed as a detection value (distance) on the display unit. Become. In this case, when the threshold value is displayed on the 7-segment display window 6, it is displayed on the same scale as the detected value (distance), and is a value that can be directly compared with the detected value (distance).

Datum tuning (FIGS. 19 and 20) :
In this tuning method, the surface shape of the detection target W is complicated, the surface is a material with little diffuse reflection such as metal, or the detection target W is a translucent body and the detection position is optically stable. This is suitable for a case where the material is difficult to perform, and when the position of the background object is stable along the detection direction (measurement distance direction) of the photoelectric switch.

  For example, when the detection target W of the mirror body is conveyed by the conveyor, when the presence or absence of the detection target is determined, the specular body has an extremely small amount of diffuse reflection components. The reflected light hardly returns to the photoelectric switch. In such a case, the photoelectric switch cannot determine whether the detection object is too far away to return the reflected light, or whether the reflected light does not return due to the surface tilt state of the specular body. There is a risk of false detection with the set threshold value.

  Datum tuning is a setting for determining whether there is only a background object in the detection target region and other states and determining the presence or absence of the detection target W. In the above example, the surface tilt state of the mirror body Even if the reflected light does not return due to, it is determined that the reflected light does not return because some object exists, that is, it is determined that the detection target W exists, and a detection signal indicating the presence of the object is output (ON output) )

  In this photoelectric switch 100, normal datum tuning (FIG. 19) and high-sensitivity datum tuning (FIG. 20) are achieved by a combination of short pressing (for example, 1 second or less) and long pressing (for example, 3 seconds or more) of the SET button 22. Are selectively executed.

  In datum tuning, the SET button 22 is pressed for a short time when only the background object is in the detection target area, and then the SET button 22 is pressed for a long time while only the background object is in the detection target area. When the control circuit determines that the SET button 22 has been pressed for a long time, “Set” is displayed on the display unit to notify the user that the long press has been detected. In this way, a detection value (distance) in a state where only the background object is present in the detection target region is captured. When the control circuit determines that the background object has been stably detected from the detection value (distance) captured by datum tuning, the detection value (distance) in a state where only the background object exists in the detection target region is set to a predetermined value. In addition to setting the threshold value as the threshold value, the 7-segment display window 6 (display section) displays “0 (zero)”, and datum tuning is performed. Turn on the indicator. After a certain period of time (for example, after 3 seconds), the detected value (distance) is displayed again on the 7-segment display window 6 (display unit), and an indicator indicating datum tuning continues to be lit. After the threshold is set, a detection operation is performed according to the set threshold.

  If the control circuit determines that the background object could not be stably detected from the detection value (distance) captured by datum tuning, an indication that the threshold value could not be set on the display unit, for example, “− "---" or the like is displayed, and after a predetermined time has elapsed (for example, after 3 seconds have elapsed), the detection value (distance) is displayed again on the display unit 7-segment display window 6 (display unit).

  The detection value (distance) after execution of datum tuning is shifted so that the value of the state where there is only a background object in the detection target region is 0, and is shifted to the 7-segment display window 6 (display unit). The detected value (distance) is displayed. Further, the detection value (distance) is displayed so that the detection value (distance) increases as the distance from the photoelectric switch 100 increases. By displaying in this way, when there is only a background object in the detection target region, the detection value (distance) is displayed on the 7-segment display window 6 (display unit) as “0 (zero)”. On the other hand, when a detection target exists in the detection target region, a value corresponding to the height (thickness) of the detection target is displayed on the 7-segment display window 6 (display unit) as a detection value (distance). As a result, the display is intuitive and easy to understand. In this case, when the threshold value is displayed on the 7-segment display window 6 (display unit), the threshold value is displayed on the same scale as the detected value (distance) and can be directly compared with the detected value (distance).

Full auto tuning (Figure 21) :
Full auto tuning is a tuning method used when the detection target W is transported and a threshold value is set (teaching) in the transported state. Threshold value that can divide the distribution of detected values (distance) into two groups based on the distribution of detected values (distance) captured during full auto tuning. An intermediate value between the maximum value and the minimum value of the distribution is set as a threshold value.

  In this full auto tuning, the distribution of detected values (distance) cannot be divided into two groups from the distribution of detected values (distance) captured during full auto tuning. When the control circuit determines that the difference between the maximum value and the minimum value is not sufficient to be detected stably, maximum sensitivity setting tuning is executed instead of full auto tuning. Full-auto tuning assumes that detection values (distance) corresponding to the object to be detected and background are obtained alternately during tuning, and the distribution of detection values (distance) can be divided into two groups. The maximum sensitivity setting tuning assumes that only the detection value (distance) corresponding to the background is obtained during teaching. When the maximum sensitivity setting tuning is executed, a value that does not detect the background and that can easily detect the detection target is set as a threshold value, and the set threshold value is the 7-segment display window 6. (Display section).

  If the control circuit determines that the distribution of detected values (distance) cannot be divided into two groups from the distribution of detected values (distance) captured during full auto tuning, do not set a new threshold value. The threshold value before the teaching operation may be maintained as it is, and the detection value (distance) may be displayed again.

  As described above, the photoelectric switch 100 is configured such that different teaching methods are executed by a combination of short pressing (for example, 1 second or less) and long pressing (for example, 3 seconds or more) of the SET button (teaching switch button) 22. Therefore, when full auto-tuning is executed, the detection value (distance) is captured by holding down the SET button (teaching switch button) 22 while the detection target is being conveyed. .

  Then, the distribution of detection values (distance) can be divided into two groups from the distribution of detection values (distance) captured during full auto tuning. When the control circuit determines that the difference from the minimum value is stable enough to be detected stably, the value that divides the distribution of the detection value (distance) into two groups is simply the detection value. An intermediate value between the maximum value and the minimum value of the (distance) distribution is set as a threshold value (set value), and the set threshold value is displayed on the display unit. After the second), the detection value (distance) is displayed again on the display unit. After the threshold is set, a detection operation is performed according to the set threshold.

  The distribution of detected values (distance) cannot be divided into two groups from the distribution of detected values (distance) acquired during full auto tuning. For simplicity, the maximum and minimum values of the distribution of detected values (distance) If the control circuit determines that there is not enough difference to be detected stably, the threshold value is not set, the value before teaching operation is maintained as it is, and the 7-segment display window 6 (display unit) displays that the threshold value could not be set, for example, “----” or the like. After a predetermined time (for example, after 3 seconds), a 7-segment display window 6 is displayed. The detection value (distance) is again displayed on the (display unit).

  The detection value (distance) after execution of full auto tuning is such that the value far from the photoelectric switch 100 among the detection values (distance) acquired during execution of full auto tuning is “0 (zero)”. Are shifted, and the shifted detection value (distance) is displayed on the 7-segment display window 6 (display unit). Further, the detection value (distance) is displayed so that the detection value (distance) increases as the distance from the photoelectric switch 100 increases. By displaying in this way, when there is only a background object in the detection target region, the detection value (distance) is displayed on the 7-segment display window 6 (display unit) as “0 (zero)”. On the other hand, when the detection target W exists in the detection target area, a value corresponding to the height (thickness) of the detection target is displayed as a detection value (distance) on the 7-segment display window 6 (display unit). Therefore, the display is intuitive and easy to understand. In this case, when the threshold value is displayed on the 7-segment display window 6 (display unit), the threshold value is displayed on the same scale as the detected value (distance) and can be directly compared with the detected value (distance).

Operation mode (FIGS. 22 to 28) :
Immediately after the power is turned on or after the above-described teaching mode ends, the mode automatically switches to the operation mode (normal operation mode).

  In the operation mode, the detected value (distance) is numerically displayed on the 7-segment display window 6 (display section), and the UP button 18 or the DOWN button 20 is pressed to switch from the distance display to the threshold display. (FIG. 22). Referring to FIG. 22 again, after switching to the threshold value display, if the UP button 18 is operated, the threshold value can be adjusted to increase. On the other hand, when the DOWN button is operated, the threshold value can be adjusted to decrease. Then, when the depression of the UP button 18 and the DOWN button 20 is stopped, the adjusted threshold value is displayed on the 7-segment display window 6 (display unit). If the non-operation state in which the UP button 18 and the DOWN button 20 are not operated is continued for a certain time, for example, 3 seconds, the display of the 7-segment display window 6 (display unit) returns to the display of the detection value (distance).

  The output switching in the operation mode will be described with reference to FIG. 23. When the UP button 18 is pressed for a long time in normal operation (during operation in the operation mode), the display mode is switched to the output logic switching. When the mode changes to the mode for setting the output logic switching, the 7-segment display window 6 (display unit) displays “L.ON” indicating that the detection output is ON output closer to the photoelectric switch 100, or “D.ON” is displayed to indicate that the detection output is ON output at a distance farther than the photoelectric switch 100. By operating the UP button 18 or the DOWN button 20, “L.ON” and “D. .ON "are alternately switched, and the display of the 7-segment display window 6 (display unit) is switched accordingly. When the non-operation state in which the UP button 18 and the DOWN button 20 are not operated is continued for a certain time, for example, 3 seconds, the display of the 7-segment display window 6 (display unit) returns to the detection value (distance).

  If the DOWN button 20 is pressed and held during operation in the operation mode, the mode can be changed to the function setting mode (FIGS. 24 and 25). In this function setting mode, when the DOWN button 20 is pressed and held, the normal state (operating state) is restored. Further, when the DOWN button 20 is pressed for a short time, the setting item transitions in the forward direction, and when the co-pressing operation for operating both the UP button 18 and the DOWN button 20 is performed, the setting item transitions in the reverse direction. The meanings of “response time”, “delay timer”, “timer time”, “hold function”, “shift function”, “clamp function”, “display”, and “end” shown in FIGS. explain.

“Response time” (FIG. 24) :
When the characters “SPd” are displayed on the 7-segment display window 6 (display unit), “SPd” means “response time”. By operating the UP button 18, the response time required for detection is displayed. Can be selected. Specifically, “10 ms” is the standard, and “50 ms” and “1.5 ms” can be selected. The longer the response time is set, the more stable the ability to detect a difficult-to-detect object such as a detection object with a small amount of reflected light.

"Delay timer" (Fig. 24) :
When the character “dLy” is displayed on the 7-segment display window 6 (display section), this “dLy” means “delay timer”, and the type of the delay timer is selected by operating the UP button 18. it can. “Off” is a delay timer function cancellation, “Ond” is an on-delay timer, “oFd” is an off-delay timer, and “Sht” is a one-shot timer. It is used for the purpose of avoiding an erroneous output at a difficult-to-detect location such as an edge portion of the detection target, or for the purpose of matching the characteristics of the input circuit of the control device that receives the detection output of the photoelectric switch.

“Timer time” (FIG. 24) :
When the character “dt” is displayed on the 7-segment display window 6 (display unit), this “dt” means “timer time”. By operating the UP button 18, the set delay timer is set. Function timer time can be set. This item is skipped when the delay timer function is cancelled.

“Hold function” (FIGS. 25 and 26) :
When “HLd” is displayed on the 7-segment display window 6 (display section), this “HLd” means “hold function”, and the detected value displayed by operating the UP button 18 A function for holding the maximum value or the minimum value of (distance) can be set. “Off” means canceling the hold function, “P_H” means holding the maximum value, and “b_H” means holding the minimum value. After setting, when both the UP button 18 and the DOWN button 20 are pressed for a short time in the normal state (operating state), the display of the 7-segment display window 6 (display unit) displays the selected hold value and the detected value (distance). Can be switched. When the selected hold value is displayed, the contents of the selected hold function and the hold value are automatically displayed alternately (FIG. 26).

“Shift function” (FIGS. 25 and 27) :
When “SFt” is displayed on the 7-segment display window 6 (display unit), this “SFt” means “shift function”. By using this shift function, the display during tuning can be shifted as can be seen from FIG.

“Clamping function” (FIGS. 25 and 28) :
When “cLP” is displayed on the 7-segment display window 6 (display section), this “cLP” means “clamp function”. By setting the clamp function to “ON”, when the light from the detection target W cannot be received, the display value and the output state immediately before that can be held.

“Display” (FIG. 25) :
When “dSP” is displayed on the 7-segment display window 6 (display unit), this “dSP” means “display” and is displayed on the 7-segment display window 6 during normal operation (during operation). The target to be selected can be selected. “On” shown in FIG. 25 means that the detected value (distance) is displayed numerically, “Off” means no display, and “BAr” means bar display. Even if “Off” or “BAr” is selected, when the UP button 18 or the DOWN button 20 is operated, the numerical value of the detection value (distance) can be displayed for a certain period of time. When the UP button 18 or the DOWN button 20 is further operated, the above-described manual adjustment of the threshold value becomes possible.

“End” (FIG. 25) :
It is a display item that explicitly notifies the end of the function setting mode, and the characters “End” are displayed in the 7-segment display window 6 (display section).

  In the first embodiment described above, an example is shown in which a laser is used as the light projecting element and a one-dimensional CMOS sensor is used as the light receiving element. However, as a modification, for example, an LED may be used as the light projecting element. Alternatively, a two-dimensional element, CCD, PSD, multi-segment PD, or the like may be used as the light receiving element. Moreover, although the example which comprised 7 segment display window using LED was shown, a liquid crystal etc. may be used and a matrix display element may be used.

Second Example (FIGS. 29 to 41) :
The photoelectric switch of the second embodiment has outer dimensions of 33 mm in length, 20 mm in width, and 11 mm in depth, and is relatively smaller than the photoelectric switch of the first embodiment described above. Similar to the first embodiment, the photoelectric switch of the second embodiment also includes a stainless steel casing manufactured by a metal injection molding method. The photoelectric switch of the second embodiment employs a photodiode (PD) as a light receiving element, the object detection principle is light quantity, and the object detection is output by an ON / OFF signal. Similarly to the first embodiment, the photoelectric switch of the second embodiment also has a relatively large output indicator lamp, and has a seven-segment display that displays the amount of received light. Moreover, it has a trimmer screw operated by the user, and the sensitivity of the amount of received light can be adjusted by operating this trimmer screw.

  FIGS. 29-31 is a figure which shows the external appearance of the photoelectric switch 200 of 2nd Example. FIG. 29 is a view of the photoelectric switch 200 provided with the light projecting / receiving window as viewed obliquely from the front, and FIG. 30 is a view of the rear surface provided with the 7-segment display window as viewed from the oblique rear (the illustration of the cable is omitted). FIG. 31 is a side view of the photoelectric switch 200. Note that FIG. 29 is shown with an output indicator lamp cover 266 described later omitted. FIG. 30 is illustrated with a 7-segment display cover 262 described later omitted.

  29-31, the photoelectric switch 200 of the second embodiment is similar to the first embodiment described above in that a stainless steel casing 202 and a stainless steel flat plate bonded to one side thereof are used. The outer contour is formed by the lid plate 204 (FIGS. 30 and 31). The casing 202 is manufactured by a metal injection molding method. As in the first embodiment, the housing 202 has a shape in which one of the four corners of the rectangle in side view is diagonally cut out, and the side on which the diagonally cut out corner is located. 7 segment display window 206 is provided (FIG. 30), and a light projecting / receiving window 208 is provided on the opposite side (FIG. 29).

  As shown in FIGS. 29 to 31, the photoelectric switch 200 is provided with switch installation holes SH at the upper end and the lower end of the front portion, and bolts (not shown) inserted through the switch installation holes SH. The photoelectric switch 200 is installed at a desired position using.

  A cable 212 is positioned at a corner 210 having an obliquely cut shape (FIG. 31), and power is supplied to the photoelectric switch 200 through the cable 212 and a detection signal, that is, ON / OFF from the photoelectric switch 200 to an external device. A signal is output. Output indicator lamps 216 (FIGS. 29 to 31) are arranged at diagonally opposite corners 210 where the cables 212 are located and opposite corners. 29 and 31, the output indicator lamp 216 has a shape extending from the front end portion of the upper surface to the upper end of the front surface (FIGS. 32 and 33), and from the upper surface of the housing 202. It has a shape protruding upward.

  FIG. 34 is an exploded view of the photoelectric switch 200. The housing 202 has a peripheral wall 220 and has a box shape with one side wall and the other side open, and the above-described 7-segment display window 206 and light projection window 208 are formed on the peripheral wall 220. Has been. The shape of the housing 202 and the arrangement of the 7-segment display window 206 and the light projecting / receiving window 208 are the same as those in the first embodiment. A side opening of the box-shaped housing 202 is indicated by reference numeral 222.

  Still referring to FIG. 34, the built-in component group 224 filled in the housing 202 includes a built-in module fixing frame 230 made of a resin molded product, a 7-segment module 232, an indicator / relay board 234, and a power / control. A substrate 236 and an element holder 238 are included. In the element holder 238, a photodiode 240 (PD: light receiving element), an LED (light projecting element) 242, and a light projecting and light receiving lens 244 are incorporated. In the housing 202, a cable substrate 250 and a holder 252 for holding the cable substrate 252 are assembled. 32 is an insulating sheet, and this insulating sheet 254 is interposed between the lid plate 204 bonded to the peripheral edge of the side opening 222 of the housing 202 and the power / control board 236. Is done.

  The housing 202 is a light source of a light-transmitting resin molded product lens cover 260, a light-transmitting resin molded product 7-segment display cover 262, and an output indicator lamp 216 from the outside. LED 290 and 292 (FIG. 40) are arranged in the width direction of the photoelectric switch 200, and the display light source board 263 incorporating two different color LEDs, a holder 265 for holding the LED, a light diffusion component 264, and outward. An output indicator lamp cover 266 of a resin molded product having a shape projecting toward is attached. This output indicator lamp cover 266 has an L-shaped cross section, and has a front extension 266b that hangs downward from the front end of the cover body 266a located on the upper surface of the photoelectric switch 200.

  The light diffusing component 264 is assembled to the casing 202 from the outside of the casing 202 via the packing 268, and an output indicator lamp cover 266 surrounding the indicator lamp light source component 264 is bonded to the casing 202. Similarly, the lens cover 260 and the 7-segment display cover 262 are also bonded to the housing 202.

  Reference numeral 270 shown in FIG. 32 and the like indicates a trimmer screw. The sensitivity of the photoelectric switch 200 can be adjusted by rotating the trimmer screw 270 clockwise or counterclockwise (FIG. 35). More specifically, the trimmer screw 270 can change the gain of the variable amplifier circuit by accessing the trimmer of the variable resistor that constitutes a part of the variable amplifier circuit. It is preferable that the portion for accessing the trimmer is made of an insulating material and the others are made of metal.

  The 7-segment module 232 described above includes a 7-segment LED board 274 and a reflector 276 with reference to FIG. 36, and the reflector 276 is installed in a 7-segment display window 206 opened in the housing 202. The reflector 276 substantially defines the shape of each segment. The reflector 276 is a member made of a plate-like insulating material in which an opening corresponding to the shape of each segment is formed. The inner wall of the opening is white or It is made of a highly reflective material such as metallic luster. The light emitted from the LED corresponding to each segment of the 7-segment LED substrate 274 is reflected by the inner wall of the aperture corresponding to the shape of each segment of the reflector 276, and each segment can be displayed without unevenness. It is preferable that a light diffusion sheet is interposed between the reflector 276 and the 7-segment display cover 262 so that display unevenness in each segment is eliminated.

  FIG. 37 is an enlarged view of the portion indicated by the arrow X37 in FIG. Referring to FIG. 37, a first step 280 for bonding the lid plate 204 is formed in the side opening 222 of the metal casing 202. A second step 282 for bonding the lens cover 260 is formed at the peripheral edge of the light projecting / receiving window 208 of the metal casing 202. As can be seen from FIG. 36, the second step portion 282 of the light projecting / receiving window 208 extends to the vicinity of the back surface of the housing 202, while the first step portion 280 of the side opening 222 is displaced to a position away from the front surface. ing. That is, the light emitting / receiving window 208 is designed to be as large as possible. As a result, it is possible to employ a relatively large lens cover 260 that emphasizes the performance as a photoelectric switch while being a relatively small casing 202.

  A built-in component group 224 is incorporated into the housing 202 through the side opening 222. FIGS. 32 and 38 show the housing 202 after the built-in component group 224 is incorporated. After incorporating the built-in component group 224, referring to FIG. 32, the contact of the power / control board 234 and the contact of the cable board 250 are soldered, and the contact of the power / control board 234 and the 7-segment LED board 274 The contacts are soldered. Referring to FIG. 38, the contact of power / control board 234 and the contact of indicator / relay board 234 are soldered. Thereafter, the lid plate 204 is bonded to the housing 202.

  Referring to FIG. 39, built-in module fixing frame 230 included in built-in component group 224 urges 7-segment module 232 toward 7-segment display window 206, and projects and receives an optical system module including element holder 238. It is biased toward the window 208 side.

  FIG. 40 shows the light diffusing component 264 and the display light source substrate 263. On the display light source substrate 263, two display LEDs 290 and 292 having different colors separated from each other in the width direction of the photoelectric switch 200 are mounted. The display light source substrate 263 is biased toward the front side by the built-in module fixing frame 230, and the front end of the light diffusion component 264 enters the recess 294 of the housing 202, thereby positioning the display light source substrate 263. Is called.

  36, in the photoelectric switch 200 of the second embodiment, the distance L1 between the 7-segment display module 232 and the lens 244 of the optical system module is larger than the width OW of the side opening 222 of the housing 202. Nevertheless, the reflector 276 is disposed in the 7-segment display window 206 of the housing 202, and the reflector 276 and the 7-segment LED board 274 are separated from the optical system module and incorporated into the housing 202. Then, by adopting a process of soldering the power / control board 234 and the 7-segment LED board 274, it can be incorporated into a relatively small casing 202. In other words, the light source switch 200 according to the second embodiment can adopt a relatively large optical system module while being a relatively small casing 202.

  The reflector 276 that constitutes a part of the 7-segment display member preferably has a shape whose outer contour is complementary to the 7-segment display window 206 of the housing, and all or a part of the reflector 276 is the housing 202. The reflector 276 may be positioned by the 7-segment display window 206 by being positioned in the portion of the 7-segment display window 206.

  In the photoelectric switch 200 of the second embodiment, the 7-segment LED substrate 274 and the reflector 276 are integrated as a 7-segment module 232, and the 7-segment module 232 is fixed to the internal module fixing frame. A reflector 276 is positioned (FIG. 34).

  FIG. 41 is a block diagram of the photoelectric switch 200 of the second embodiment. The photoelectric switch 200 outputs a detection signal (ON / OFF signal) corresponding to the amount of received light. More specifically, the light from the LED 242 according to the LED drive circuit is projected toward the detection area, and the reflected light from the detection target W in the detection area is received by the photodiode (PD) 240. The PD 240 amplifies the received light signal according to the received light amount by the variable sensitivity amplifier circuit, and the control circuit compares it with a predetermined threshold value and outputs a detection signal. The threshold is fixed. By adjusting the rotation angle of the trimmer screw 270, the sensitivity (amplification factor of the received light signal, etc.) can be adjusted. That is, the sensitivity is manually variable and adjustable. In the second embodiment, by adjusting the sensitivity adjustment trimmer screw 270, the amplification factor of the variable amplifier circuit can be adjusted to the amplification factor according to the rotation angle of the sensitivity adjustment trimmer screw 270. The detection signal is output by comparing the light reception signal amplified by the variable amplifier circuit with a fixed threshold value (for example, “100”) stored in the memory. The indicator lamp 264 performs ON / OFF lighting display in conjunction with the detection output (ON / OFF output). The 7-segment display unit 206 numerically displays the received light amount according to the amplified received light signal. Therefore, the received light amount displayed is variable according to the rotation angle of the trimmer screw 270 even if the state of the detection object is the same. The photoelectric switch 200 according to the second embodiment does not have a setting mode or display switching as in the first embodiment.

  In the second embodiment described above, an example in which an LED is used as the light projecting element has been described. However, for example, a laser diode may be used as the light projecting element. Moreover, although the example which comprised 7 segment display window using LED was shown, a liquid crystal etc. may be used and a matrix display element may be used. In addition, although the example in which the threshold value is fixed and the sensitivity (amplification factor) of the analog circuit is adjusted by the trimmer screw 270 has been shown, the sensitivity (amplification factor) may be adjusted digitally, You may comprise so that analog and digital may be mixed and adjusted. Further, instead of changing the sensitivity (amplification factor) with the trimmer screw 270, or in addition thereto, the threshold value may be adjusted with the trimmer screw 270.

DESCRIPTION OF SYMBOLS 100 Photoelectric switch of 1st Example 2 Metal housing 4 Flat cover plate 6 7 segment display window 8 Light emitting / receiving window 16 Output indicator 18 UP button 20 DOWN button 26 Surrounding wall of housing 28 One side of housing Side wall 30 Side opening of housing 36 7-segment display component 40 7-segment display cover 42 Light diffusion component 44 Output indicator cover 50 Emitter / receiver substrate 52 Distance display / control substrate 54, 56 Output display LED
232 7-segment module 262 7-segment display cover 264 Light diffusion component 274 7-segment LED board 276 Reflector

Claims (8)

A light projecting element that projects light toward the detection area;
A light receiving element that receives light from the light projecting element reflected by the detection region and outputs a signal corresponding to the received light;
A control unit that calculates a detection value corresponding to an amount of light received or a distance based on the signal from the light receiving element, and outputs a detection output based on the calculated detection value and a predetermined threshold;
An output indicator lamp for displaying according to the detection output;
A display member for displaying the detected value;
A metal housing that houses the light projecting element, the light receiving element, the control unit, and the display member;
A metal plate member for closing one side opening formed on one side wall of the walls of the metal housing;
A display window for displaying the detection value formed on the other wall of the housing orthogonal to the one side wall provided with the one side opening and displayed by the display member;
A step portion constituting an opening peripheral edge portion of the display window;
A display cover fixed to the stepped portion and covering the display window;
The photoelectric switch, wherein the display cover and the display member are located in the display window.   The photoelectric switch according to claim 1, wherein an outer surface of the display cover is flush with an outer surface of the metal casing at a peripheral edge of the display window.   The photoelectric switch according to claim 1, wherein the display cover has an outer surface curved in a vertical direction of a numerical value displayed by the display member.   The said display member has 7 segment LED, the reflector arrange | positioned on the outer side of this 7 segment LED, and the light-diffusion sheet | seat arrange | positioned on the outer side of this reflector. Photoelectric switch. The output indicator lamp has an output indicator LED and an output indicator lamp cover covering the output indicator LED;
The photoelectric switch according to any one of claims 1 to 4, wherein the output indicator lamp cover has a shape protruding outward. It further has a light diffusing component interposed between the output display LED and the output indicator cover,
The photoelectric switch according to claim 5, wherein the output indicator cover is larger than the light diffusion component. Further comprising an UP button and a DOWN button arranged on one wall of the housing and arranged to project outward from the wall surface of the one wall;
The photoelectric switch according to any one of claims 1 to 6, wherein the wall surface of the one wall is configured by a curved surface protruding outward in a cross section thereof. The UP button and the DOWN button are spaced apart in the longitudinal direction of the one wall,
The photoelectric switch according to claim 7, wherein the UP button and the DOWN button are arranged at the center in the width direction of the one wall.

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