JPS60186701A - Photoelectric device - Google Patents

Abstract

PURPOSE:To easily make a front surface flat so that light is prevented from straying and stains on the surface are cleaned up easily by coupling tips of light shield cylinder parts for projection and photodetection with the light shield member of a dust protective plate. CONSTITUTION:The dust protective plate 3 consists of an insert plate 31 made of a light-transmissive member and the light shield member 32 which is formed integrally with the insert plate 31 so that the front and rear surfaces of the insert plate are covered. The light shield member 32 is formed to surround window parts 31a-31c on the front surface of the insert plate 31 and also separate them optically from one another. Tips of a light shield cylinder part for projection which contains a projection part A and a light shield part for photodetection which contains photodetection parts B and B' are coupled with the light shield member 32 of said dust protective plate. Consequently, light is prevented from straying between the projection part and photodetection parts and its front surface is made flat easily to facilitate the cleaning of stains.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is for projecting light such as infrared rays and detecting the anti-AJ light to measure the presence or absence of an object or the distance 1 to the object. relating to photoelectric devices.

(Prior art) This type of photoelectric device is used as one of the production sensors in a factory to determine whether an object has passed in front of it, or to identify whether or not an object has passed in front of it, or if high precision is required. It is used to detect whether an object has passed within the distance.

The light emitting part and the light receiving part of such a photoelectric device are the 12th
As shown in the figure, one cylinder part 71a of the light-shielding cylinder 71 is used for light emission, and the other cylinder part 71b is used as a Y river, and the light projection part ear 21 is placed in the back of one cylinder part 71a. The other cylindrical part 71
A light-receiving element 722 is attached to b, and one cylindrical portion 71a is installed.
4.1 on the front! J! : Optical lens;
'132 is held (fixed) by a light-shielding holding frame 74. 75 is a main body case to which the light projecting section and the light receiving section configured as described above are attached.

By the way, dirt adhering to both condensing lenses 731 and 732 will affect the performance of the photoelectric device, so it must be avoided.
Although it is necessary to remove it by sweeping t#, in the above configuration, there is always a step between the presser frame 74 and the condensing lenses 731 and 73. Therefore, if there is a difference in level, it is important to completely clean it.

Therefore, as shown in FIG. 13, a lens 76 is constructed in which a condensing lens for light emission and light reception is integrated, and the lens part 76'a on one side is used for light emission, and the lens part 76b on the other side is used There are some with a flat front surface for receiving light. With this configuration, there is no step on the front surface, so it is easy to clean dirt on the front surface. However, in this case, the tip portions of the light projecting tube ffH71a and the light receiving tube 71b are optically coupled by the intermediate portion 76c of the lens 76, causing light to circulate between them.

In order to completely eliminate this light circulation, lens 7
Although it is necessary to eliminate the transparent intermediate portion 76c of Figure 6, there is a problem that a population problem will arise in Figure L2.

(Purpose of the Invention) The present invention has been made in response to these points, and its purpose is to prevent the penetration of light by +1, and to clean the dirt of 011011. It is an object of the present invention to provide a photoelectric device that can be easily formed so that its front side is flat so as to provide a 1-fit.

(Structure of the Invention) For this purpose, the present invention includes a light projecting element, a light projecting condensing lens located in front of the light projecting element, and a top d'' light projecting element and the above light projecting condensing lens. A light projecting section composed of a light shielding tube section for projecting light, a light receiving element that receives reflected light from a detected object of the light projected from the light projecting section, and a condensing lens for light receiving located in front of the gizzard optical element. , and the light receiving element and the light receiving condensing lens I! a light-receiving section composed of a light-receiving light-shielding cylinder section to accommodate the light-receiving part;
2. A light-emitting window covering the front surface of the light-emitting part and a dust-proof plate formed by separating the light-receiving window part covering the front surface of the light-receiving part by a light-shielding member, the light-emitting light-shielding cylinder part A tip of the light-receiving light-shielding cylinder portion is coupled to the light-shielding member of the dustproof plate.

(Example) Hereinafter, an example of the photoelectric device of the present invention will be described with reference to the drawings. As shown in FIG. 1, the photoelectric device of this embodiment includes an optical unit and other components provided inside 1a of a main body case 1.
The lid 2 is closed so as to cover them (FIGS. 4 and 5). On the front surface 1b of the main body case 1, an infrared light projecting section A is provided at the center thereof, and light receiving sections B and B' are provided on both sides of the projecting section at the same distance apart. Then, the light projecting section A and the light receiving sections B, B
' constitutes an optical unit I. Further, on one side surface 1c adjacent to the front surface 1b described above, there is a distance setting section C for setting a detection distance area and a distance for indicating when an object to be detected enters the set distance area. A display section is provided. Furthermore, a cord connecting portion 11 is provided at a corner portion of the back surface.

” 2. The forward direction of the light emitting section and the light receiving section B, B' is
It is covered with a dustproof plate j3 as shown in FIGS. 2 and 3. This dustproof plate 3 is integrally attached to the insert plate 31 so as to cover the inserts 1-1 & 31 made of a transparent member such as a red transparent part shrine, and the front and back sides of the insert plate 31. It is constituted by, for example, a black light shielding member 32 which has a light shielding property and is formed by two-color molding of +l14 resin.

That is, the insert plate 31 has a protruding shape such as a dustproof window 31a of the light receiving section 13', a dustproof window 31c of the light receiving section B, and a dustproof window 31c of the light receiving section B. , are formed separated in the alignment direction by slits 31d, 31d having stepped portions, and the respective window portions 31a to 31c (7) are connected to the upper and continuous viscosity nH3i e, 31e. There is.

On the other hand, the light shielding member 32 is the inserter I.$1. j 3 J
On the front side, a window frame portion 32a is formed to surround each of the window portions 31a to 31c to optically separate them, and on the back side, a flange portion 32b for suspending the O-ring 4 is formed. It is formed. This collar part 32
The notch 32 formed in b is used for positioning a lens, which will be described later. Also, in the window frame portion 32a, the slit 3
A recess 32e into which the tip of a light-shielding tube 5 (to be described later) fits is formed on the back surface of the light-shielding portion 32d that is embedded in 1d and continuous between the front and back sides.

Therefore, this dustproof plate 3 has no step or the like at the boundary between the front surfaces of the window sections 31a to 31c and the front surface of the window frame section 32a, and is flat and flat, so that dust does not adhere to the front surface. Even if the window portions 318 to 31c are exposed to air, the entire front surface of each of the window portions 318 to 31c can be easily cleaned with a cloth or the like. In addition, the window portion 31a~
31c, the mutually adjacent portions are the light shielding portions 32d of the light shielding member 32.
Since the window portions 318 to 31C are separated by the window portions 318 to 31C, the phenomenon of light going around does not occur between the window portions 318 to 31C. Furthermore, the light shielding member 32 is integrated with the insert plate 31 by integral molding in which the resin of the light shielding member 32 is passed through both the front and back sides of the insert plate 31, so the connection between the two is complete and there is no possibility of separation. do not have.

The light-shielding tube 5 described above is a tube section (not shown) for the light receiving section B'.
, a cylindrical part 5b for the light projecting part A, and a cylindrical part 5c for the light receiving part B, and the tip of the partition wall 5d that separates each cylindrical part is located in the recess of the light shielding part 44'32 of the dustproof plate 3, as described above. 32e, and the tip of the outer peripheral portion 5e fits inside the flange 32b of the light shielding member 32.

Therefore, for example, between the cylindrical part 5b and the cylindrical part 5C, the abutment surface between the recess 32e of the light shielding member 32 and the tip 1 of the partition wall 5d becomes an optical path, but since the path is curved, the light passes through. There is no fear that it will.

A condensing lens for light reception is placed in the cylindrical portion for the light receiving section B', a condensing lens 62 for light emission is placed in the cylindrical section 5b for the light emitting section A, and a condensing lens 62 for light emission is placed in the cylindrical section 5C for the light receiving section B. A condensing lens 63 for receiving light is arranged respectively. The q5 optical lens 62 is attached as shown in FIG.
2a into the notch 32c of the light shielding member 32 of the dustproof plate 3, and press the tips of the -L plate part 5h and the lower plate part 5i of the light tube :) with the 11. The same applies to other condensing lenses≦
l.

A light projecting element (light emitting diode) 8 is attached to the inner valve of the cylindrical portion 5b of the light projecting section B via an IJ and an aperture 7 (FIG. 4).

Further, a force 41 portion 5f is formed at the back of the cylindrical portion 5C of the light receiving portion B by the upper piece 5f+, the upper piece 5f2, and the protrusion 5f3, and the body 92 is forcefully guided by the guide portion 5f. ing. 92a is a recess that fits into the projection 5fz. A position detection light receiving element (P
SD) 102 is fixed and held by adhesive or the like. Reference numeral 11 is a filter for cutting off unnecessary wavelength regions (FIG. 5).

This position detection light receiving element 102 has a horizontally long light receiving section 102.
a, and the reflected beam from the object to be detected is transmitted to the light receiving part 1.
The output current is changed depending on the position in the longitudinal direction of 02a where the light is received. 102b is a bias terminal, and 102C and 102d are output terminals.

At this position detection light receiving element 102 (:l, its holder 92 is provided so as to be movable in the direction of the arrow X, thereby making the position detection light receiving element 102 itself movable in the longitudinal direction That is, a hole 5g is formed in the upper piece 5f+ of the guide part 5f at the back of the cylindrical part 5C, and a long groove 92b is also formed in the holder 92.

The eccentricity 122 is installed so that the main body 122a enters the hole 5g and the pin 122b enters the long groove 92b. 122c is a groove for a driver.

Note that the eccentricity of the pin 122b from the axis of the main body 122a is shown (FIGS. 7 and 8).

Therefore, when a screwdriver is applied to the groove 122c and the eccentric amount 122 is rotated, the pin 122b moves within the long groove 92b, so that the entire holder 92 moves to the upper piece 5f of the guide portion 5f! ,
The lower piece 5f2 and the protrusion 5f.

It moves a maximum distance of 2 L in the direction of arrow X. Therefore, since the position detection light receiving element 102 also moves in the same way, its position can be adjusted.

To explain this point in more detail with reference to Figure 9,
If the eccentricity 122 is rotated in the direction of the arrow α, a force E is applied to the holder 92 and at the same time a force F is applied to the eccentricity 122.
is added. In this case, if the lower surface 92c of the boulder 92 is used as the abutment surface, a moment M is applied around the lower surface 92C, and the holder 92, which should normally move from side to side, moves around the lower surface 92C. At this time, a fairly large stick slip phenomenon occurs at the lower surface 92C, making left and right adjustment difficult. In order to prevent this, it is sufficient to bring the abutting surface of the force F onto the surface of the eccentric rivet 122 on which the force E acts.

In this embodiment, since it is difficult to solve the above problem in terms of space, the abutment surface that receives the force F is moved as much as possible by eccentric studs 12.
In order to bring the force closer to the surface on which force E'0') acts, a recess 92a is provided in the holder 92, and a protrusion 5 is provided in the guide portion 5f.
f3 is provided so that it is received by the fitting surface G of both. This provides a considerable improvement compared to the case where the abutting surface is the lower surface 92C.

Although one light receiving section B has been described here, the position detection light receiving element 7-101 and the holder 9 of the other light receiving section B' have been described.
1, eccentric stud] and 21 have exactly the same structure except that the entire structure is symmetrical.

Light projecting section A, light receiving section B, B' configured as above.
is provided as an optical unit of llll11 integrally with the light-shielding tube 5, and when the main body case 1 is attached, the opening 1 formed on the side 1b of the main body case 1 is opened.
d, and is installed in a water-tight structure with an O-ring 4. That is, the O-ring 4 is suspended on the outer surface of the flange 32b of the light-shielding member 32. , the step 1d+ formed at the front part of the opening 1d
When the ring 4 is inserted so that it fits, the entire optical unit 1 appears on the back of the main body 1, as shown in Figures 1, 4, 5, etc. It is installed in a watertight structure.In particular, in the structure of these few examples, when an external force is applied to the main body case 4), that external force is absorbed by the O-ring 4, so the force applied to the optical unit itself can be buffered and its adverse effects on the optical unit can be avoided.

1) As the ring 4, a ring formed during molding into a substantially rectangular shape similar to the outer shape of the flange portion 32b of the dustproof plate 3 that is fitted into the ring 4 is used. If a circular O-ring is used, not only will the ease of assembly be worse, but the corners of the dust-proof plate 3 will apply force to the O-ring, causing the O-ring to stretch locally, making waterproofing less reliable. By using the O-ring 4 which is made approximately rectangular as shown in FIG.

A distance setting section C for setting the detection distance area and a distance display section for indicating that the object to be detected has entered the set area are provided in an opening 1e formed in the side surface 1c of the main body case 1. (Figures 1 and 6). 13 is a printed wiring board, and there is a variable resistor 1 for distance setting in this part.
4 and display light source (light emitting diode) 15 for distance display
is attached, and the rotary working part 1 of the variable resistor 14 is
A knob 16 is attached to 4a via a connecting plate 17.

The printed wiring board 13 is positioned relative to the two protrusions 18a and 18b of the display body 18 made of a transparent member, and is fixed by welding one of the protrusions 18b. The display main body 18 is engaged with the opening 1e of the main body case 1 by the engaging protrusions 18c and 18d, and is prevented from being pulled out. 18e is a display window configured in a protruding shape so that it can be seen over a wide area as a lens part.a)
The surface has a rough finish.

Four parts 18 formed on the display body 18 of the knob 16
It is attached inside f via U7 through an O-ring 19 for waterproofing. Further, the front part of the display body 18 also has an O-ring 20 attached to the step 1e+ of the opening surface of the opening 1e of the body case 1.
・U (watertight structure).

21 is a nameplate, which is pasted on the step IC 1 of the main body case 1 and the front of the display main body 18 with double-sided tape. A ring-shaped sheet 22 is interposed between the name plate 2 and the knob 16 to prevent the name plate 21 and the knob 16 from adhering to each other. Therefore, there is no problem with the rotation of knob 16.

Therefore, display this distance setting part C and tfli 1ii1! 't111), these are integrated into one display block with navy blue embedded in the display body 18, which not only makes it possible to inspect the display block as an iB body, but also simplifies assembly. position adjustment when incorporating into the main body case 1 (especially position adjustment between the variable resistor and knob 16 on the printed wiring board 13, position adjustment between the display light source 15 on the printed wiring board 13 and the window 18e, etc.) ) becomes unnecessary.

FIG. 10 shows the principle of an optical system for detecting the object to be detected Q.
3 are the same distance j2o, and the distance between the condenser lens 61.63 and the position detection light receiving element 101.102 is f. Note that the position detection light receiving element 101 is a semiconductor device detection element (Position
A device known as Sen51g Device (PsD) 7 is used, and the output terminal 101C11
01d has a subo-nodohikari r' and electrodes 101e, 101.
An output current is produced that is inversely proportional to the distance to f. The same applies to the other position detection light receiving element 102. Also,
Position detection light receiving element 1 ON, 102 is the condenser lens 6
The distance from 1.63 is I! 1, which is the same as the eccentric stud 121.1 described above.
This is done by adjusting the position of the holders 91 and 92 in the direction of the arrow X by rotating 22.

Now, when infrared rays are emitted from the light emitting element 8, the light becomes a light beam P having a certain width by the condensing lens 62 and is projected onto the object to be detected Q, which is reflected as a reflected beam R. , R' are focused by silver beam lenses 61, 63 and incident on position detection light receiving elements 101, 102, respectively.

Therefore, by detecting the position of either one of the light-receiving spots r and r' generated on the position detection light-receiving elements 101 and 102, the distance β to the detected object Q can be determined by triangulation. ,given name. That is, if the distance %ill j2 is short, for example, one light-receiving spot r will be relatively biased towards the opposite side (outside) from the light projecting element 8, and if it is long, it will be relatively biased towards the light projecting element 8 side (inside). To position. Therefore, by comparing the output currents of the output terminals 102C1102d of the light-receiving element 1'02, it is possible to know where the light-receiving spoiler) r is located. Then, a comparison signal obtained by comparing both of the above output currents indicates the distance β.

Therefore, if a reference level corresponding to a predetermined distance is set by the variable resistor 14 of the distance setting section C, the detected object Q can be set by detecting whether or not the comparison signal exceeds the reference level. It is possible to detect whether or not the vehicle is within the specified distance.

Then, when the distance is within the set distance, the display light source 15 of the distance display section can be turned on. In addition, the above-mentioned light-receiving slot r is a position detection light-receiving element 1.02
Of course, the presence or absence of an object to be detected can also be detected depending on whether or not light is received by the object.

The same is true for the other position detection light receiving element 101, so it seems that only one is sufficient and both position detection light receiving elements 101 and 102 are unnecessary, but this is because the detection error is corrected. It was established in

That is, the light emitted from the light projecting element 8 is turned into a parallel light beam P by the condenser lens 62, but since the light beam P has a certain width, not all of the light beam P but one part of the light beam P is formed. When the portion is projected onto the object to be detected, a light spot of the reflected beam from the projected portion enters the position detection light receiving element, causing a detection error there. In other words, as shown in FIG.
Although the light beam J is at the same distance l as in the case of diagram O,
, P is projected onto the detected object Q', the light receiving spora l on the light receiving surface of the position detection light receiving element 102
-r position distribution is different from that in Figure 1O, and the output terminal 1
The comparison signal for comparing the output currents from 02C1102d is different from that shown in FIG. 10, and an error occurs.

Therefore, the two position detection light receiving elements 101 and 102 are provided symmetrically with respect to the light emitting element 8. If the above error occurs, the two position detection light receiving elements 101 and 102 are arranged symmetrically with respect to the light emitting element 8. The output current comparison signals 102 change in opposite directions. Therefore, by adding the outputs of the inner terminals 101c and 102C of the reposition detection light receiving elements 101 and 102, adding the outputs of the outer terminals 101d and 102d, and comparing the two added signals, the error can be canceled out. hand,
A signal indicating the correct distance %1tβ can be obtained.

(Results of the Invention) As described above, according to the present invention, the light emitting window and the light receiving window in the dustproof temporary are separated by the light shielding part, and the light emitting tube is connected to the light shielding member. Since the part and the light-receiving cylindrical part are combined, it is possible to prevent the phenomenon of light wrapping between the light-emitting part and the light-receiving part.

Second, since it is easy to form the front surface of the dustproof temporary to be flat, by doing so, the +iiJ surface can be thoroughly cleaned for each item.

[Brief explanation of the drawing]

Fig. 1 is a -L view of a photoelectric device according to an embodiment of the present invention with the lid removed, Fig. 2 is a perspective view of a dustproof plate, and Fig. 3 is a perspective view of the dustproof plate.
A cross-sectional view of the longitudinal force treated as η4, Figure 4 is a in Figure 1.
5 is a sectional view taken along line b-h, FIG. 6 is a sectional view taken along line dd, and FIG. 7 is a sectional view taken along line d-d.
4J is a cross-sectional view taken along line ee-e, FIG. 8 is a plan view of the guide portion of the holder of the light-receiving element for position detection, FIG. 9 is an explanatory diagram of position adjustment using eccentric studs, FIG. Figure 11 is an optical diagram for explaining distance %lIl measurement, Figures 12 and 13
The figure is a sectional view C showing a conventional photoelectric device. A... Light projecting section, B, F3'... Light receiving jl (, c
-#l! , t'jl setting section, 1]... distance 1iQII table small section, II... 21-1 connection section, 1... main body case, 2... lid, 3... protection 11J4 &, ;(1...
Insert plate, 32... light shielding member, 4... 0 link,
5... Light-shielding cylinder, (tl, ((2, [;;
12...Bokuto・'I'',,I (l I, j02...
Position detection light receiving element, 11...filter, 121.1
22... Eccentric rivet, 13... Cylinder 1.c! 1l
IT board, 14... I11 variable resistor for distance setting, 15.
・・Koya for small table, 16・Knob for setting Nil, 1
゛7... Connecting plate 1.13)... Main body, 19.2
0...(D ring, :21...Inscription 41zo, 22...
・Sheet. Patent applicant: Makoto Konishi Rokunai Kogyo Co., Ltd. R1 Matsushita Electric Works Co., Ltd. Representative Patent Attorney Tsuneakite Nagao Li Bi Nejlf, xiE (spontaneous) (Method)
May 8, 1981 Patent Application No. 04+781 2 Name of the invention Photoelectric device 3, Relationship to the case of the person making the amendment Patent applicant address 1-26-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Name Name
(127) Konishi Rokuyoma] - Industry Co., Ltd. and 1 other person 4, agent

Claims (1)

[Claims] (1) A light projector consisting of a light projecting element, a light projecting condensing lens located in front of the light projecting element, and a light projecting light-shielding tube portion that accommodates the light projecting element and the light projecting condensing lens. a light receiving element, a light receiving element that receives the reflected light from the object to be detected of the light projected from the light projecting part, a condensing lens for receiving light located in front of the light receiving element; A light-receiving section composed of a light-receiving light-shielding cylinder section that accommodates a condensing lens, a light-emitting window section that covers the front surface of the light-emitting section described in -, and a light-receiving window section that covers the front surface of the light-receiving section are separated by a light-shielding member. 11, and the tips of the light-emitting light-shielding cylinder part and the light-receiving light-shielding cylinder part are coupled to the light-shielding member of the dust-proof plate in 1. Photoelectric device.