JPS6158126A - Photoelectric switch - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a photoelectric switch, and more particularly to a photoelectric switch characterized by a structure in which the optical axis of an optical member is aligned with a light emitting/receiving element.

[Prior art and its problems]

A conventional photoelectric switch is composed of a circuit section such as a switching circuit, and an optical system block such as a lens provided on the front surface of the switch in alignment with the optical axis of the light emitting arm and the light receiving element. By the way, the light emitting element is driven by an electric signal, and the light receiving element needs to convert the received light into an electric signal. Therefore, in conventional photoelectric switches, the light emitting and receiving element is either provided in the switch circuit section or It is attached to a board, and the board and the circuit portion of the switching circuit are connected in advance.

However, since optical components such as lenses and circuit parts are fixed within the case, there are problems in that the distance between the lens and the light emitting/receiving element may become unstable, or the optical axes of the lens and the light emitting/receiving element may be misaligned. there were. Therefore, fine adjustments must be made to adjust the optical axis and maintain a constant distance between the lens and the light emitting/receiving element, which complicates the manufacturing process and, if these adjustments are incomplete, the detection characteristics may deteriorate. The problem is that each switch is different.

[Purpose of the invention]

The present invention has been made in view of the problems of conventional photoelectric switches, and the present invention is made by integrally forming a light emitting/receiving element, etc. and an optical member such as a lens, so that the lens and the light emitting/receiving element can be positioned at a predetermined position. The purpose of the present invention is to provide a photoelectric switch that can be connected reliably.

[Structure and effects of the invention]

The present invention is a photoelectric switch that detects an object based on the presence or absence of an optical signal, in which an optical board is attached to the back of an optical holder, and the optical holder and the optical board hold an optical member and an optical element, respectively. An optical member unit in which an optical element is integrally formed, a board unit 7) which is formed by integrating a circuit board including a board on which a detection circuit section is mounted, and an optical board of the optical member unit inside the case of the photoelectric switch. The present invention is characterized in that the base plate of the base unit and the base unit of the base unit are brought into contact with each other to electrically connect them, and the respective units are fixed.

According to the present invention having such characteristics, the light emitting/receiving element is integrally formed on the optical holder to which a lens etc. is attached as an optical member unit and the optical substrate provided on the back surface of the optical holder. It is possible to always appropriately set the distance between the lens and the light emitting/receiving element and the optical axis.

Therefore, it is possible to provide a photoelectric switch that always has stable detection characteristics without variations in characteristics from one photoelectric switch to another. Furthermore, since the board unit and the optical board of the optical member unit are connected by soldering at predetermined locations inside the case, the connection is extremely easy and the assembly work efficiency can be improved.

[Explanation of Examples]

FIG. 1 is an assembled configuration diagram showing an embodiment of a photoelectric switch according to the present invention. Resistance as shown in this figure.

A power supply circuit board 1 on which electronic components such as capacitors, transistors and coils are mounted, and a timer IC.

A timer circuit board 2 on which a timer circuit such as a transistor and a resistor is mounted is placed facing each other as shown in the figure, and an IC for detecting an object, a light emitting diode 3 for displaying operation and power supply, a resistor 4 for sensitivity adjustment, etc. are mounted on the top of the board. Amplifier circuit board 5 to be mounted
are integrally formed as shown in the figure to form a substrate unit 6.

Furthermore, an optical board 9 is attached behind a lens holder 8 that holds a second-class lens 7 provided on the front surface. As shown in the figure, projections 3a and 8b having outward claws are formed on the left and right inside of the lens holder 8. Then, the light emitting/receiving elements are installed on the optical board 8, the optical axis and the distance between the lens and the light emitting/receiving elements are accurately adjusted, and these are integrated into the optical member unit 10.
form as. Then, these board units 6 are inserted into the case 11, and a transparent plate 13 and a panel 14 in which usage conditions are written are fixed to the upper part of the board unit 6 via an O-ring 12 from the upper opening of the case 11. . Here, the transparent plate 13 has claws 13a and 13b having outward protrusions on all sides as shown in the figure.

13C and 13d are provided, and the board unit 6 is fixed in the case 11 by engaging with m1la to lid provided on four sides of the upper inner surface of the case 11. Similarly, the optical member unit 10 also has projections 8a, 8 of the lens holder 8.
b, the optical member unit 10 is fixed to the case 11 by engaging with a groove provided on the front inner wall of the case 11.

FIG. 2 is a partially cutaway sectional view of this reflective photoelectric switch after assembly. In this figure, the power supply circuit board 1 is omitted. Now, inside the case, as shown in this figure, after fixing the board unit 6 and the optical member unit 1-10 in the case 11, the optical board 9 and the amplifier circuit board 5 of each unit are fixed.
The connecting parts of the two are bridged by soldering to make an electrical connection. Then, as described above, the transparent plate 13 and the panel 14 are overlapped and fixed from the upper surface of the case 11 to form a photoelectric switch. In this figure, a light emitting element 15 and a light receiving element 16 are integrally formed on the optical substrate 9 with an optical member unit 10 as shown. In this way, the light emitting and receiving elements are formed with their optical axes and positions accurately adjusted within the lens 7 and the optical member unit 10, so there is no need to adjust these positions when attaching them to the case, making assembly easy. It becomes possible to do so.

In this embodiment, grooves are provided inside the case 11 so that the transparent plate 13 and the protrusions 13a to 13d, 8a to 8a of the lens holder 8 are provided with grooves.
8b connects the substrate unit 6 and the optical member unit 10 to the case 11, but it goes without saying that they can also be attached by screwing, heat caulking, or other methods. Although this embodiment has been explained using a reflective photoelectric switch as an example, it can be applied to either a retroreflection type or a diffuse reflection type photoelectric switch, and it can also be applied to either the light emitting/receiving part of a transmission type photoelectric switch. It is possible to apply the present invention to form a photoelectric switch.

Further, as shown in FIG. 3, it is also possible to apply the present invention to an optical fiber type photoelectric switch in which an optical fiber is fixed to a light emitting/receiving section. In this figure, the light emitting/receiving elements 15 and 16 of the optical member unit 10 are provided on the base 20. A pair of upper and lower apertures each having a female thread on the inner periphery are provided on the front surface of the base 20, and a small diameter aperture whose cylindrical axis coincides with these apertures is provided behind the aperture to hold the light emitting/receiving elements 15 and 16. ing. The pair of openings provided on the front surface of the base 20 have a through hole in the center for passing the optical fiber through, and conical tightening portions 20a and 20b, with claws inside the through holes. provided.

The clamping parts 20a, 20b are fixed to respective openings of the base 20 by clamping fittings 21, 22 having through holes along the axis. The fasteners 21 and 22 have male threads along the thread groove of the opening of the base 20, and have recesses corresponding to the conical shapes of the fastening parts 20a and 20b.

Now, the optical fibers 23 and 24 are passed through the through holes of the fastening fittings 21 and 22 and the M through holes of the fastening parts 20a and 20b of the base 20, and brought into contact with the front surfaces of the light emitting and receiving elements 1s and tM. 22, the tightening portions 20a and 2Gb of the base 20
Tighten as shown. Then, the tightening part 20a,
The optical fiber is fixed by the claws on the inner periphery of the optical fiber 20b, and it becomes possible to align the optical axes of the optical fiber 23.24 and the light emitting/receiving element 15.16 and fix them. The optical member unit 1-10 configured in this way is inserted into the case 11 in the same manner as in the embodiment described above, and connected to the board unit 6 which is similarly inserted and fixed into the case 11 to form an optical fiber type photoelectric switch. do. In this case as well, the optical member unit is integrally formed, and the base 20 eliminates the need for optical fibers and light emitting/receiving elements, making it possible to easily assemble the photoelectric switch.

[Brief explanation of drawings]

Fig. 1 is an assembled configuration diagram showing an embodiment of a photoelectric switch according to the present invention, Fig. 2 is a partially cutaway sectional view of a proximity switch after assembly, and Fig. 3 is a photoelectric switch according to the present invention using an optical fiber. FIG. 7 is a partially cutaway sectional view of a photoelectric switch showing another embodiment. 1--1---Power circuit board 2---Timer circuit board 3--Light emitting diode 4---
-One sensitivity fJ! a Adjustment variable resistor 5-----Amplifier circuit board 6---Board unit 7--Lens 8-----Lens holder 9------
Optical board 10...- Optical member unit 11.
--- Case 13 --- Transparent plate 15 --- Light emitting element 16 --- Light receiving element
20------・-Base 20 a, 20
b-----Tightening part 21, 22----
-・-Tightening fitting 23.2'4...--Optical fiber

Claims (6)

[Claims] (1) A photoelectric switch that detects an object based on the presence or absence of an optical signal, in which an optical board is attached to the back of an optical holder, the optical holder and the optical board hold an optical member and an optical element, respectively, and the optical member and an optical member unit integrally formed with an optical element; a board unit integrally formed with a circuit board including a board on which a detection circuit section is mounted; and an optical board of the optical member unit inside a case of a photoelectric switch. A photoelectric switch characterized in that the substrate of the substrate unit is brought into contact with the substrate of the substrate unit to be electrically connected, and each unit is fixed. (2) The photoelectric switch according to claim 1, wherein the optical holder of the optical member unit is a holder that holds a lens as an optical member on the front surface. (3) The photoelectric switch according to claim 1, wherein the photoelectric switch is a retroreflective photoelectric switch. (4) The photoelectric switch according to claim 1, wherein the photoelectric switch is a diffuse reflection type photoelectric switch. (5) The photoelectric switch according to claim 1, wherein the photoelectric switch is one of the light emitting and receiving parts of a transmission type photoelectric switch. (6) The photoelectric switch according to claim 1, wherein the optical holder of the optical member unit is provided with an optical fiber fixing member for fixing an optical fiber.