WO2022190551A1

WO2022190551A1 - Optical sensor

Info

Publication number: WO2022190551A1
Application number: PCT/JP2021/047172
Authority: WO
Inventors: 紘行水崎; 裕介小田
Original assignee: オムロン株式会社
Priority date: 2021-03-11
Filing date: 2021-12-21
Publication date: 2022-09-15
Also published as: JP2022139166A

Abstract

Provided is an optical sensor (1) which makes it possible to easily mount a cable (10) to a circuit substrate (3) while conserving space. An optical sensor (1) is equipped with: a housing (2) in which a through-hole (9) is formed; a cable (10) which has a plurality of wires (11, 12) comprising core wires (11) covered by inner sheaths (12), and also has an outer sheath (13) for bundling the plurality of wires (11, 12) with one another; a flange (14) which is integrally formed with the outer sheath (13) and the inner sheath (12) at an end of the outer sheath (13), and is formed to have a dimension which can pass through the through-hole (9); a stopper (15) which restricts the position (P1) of the flange (14) relative to the through-hole (9); a cover (17) which is secured to the outer surface (2B) of the housing (2) and covers the boundary (B) between the through-hole (9) and the flange (14); a first sealing material (16A) for sealing the gap (G1) between the cover (17) and the outer surface (2B) of the housing (2); and a second sealing material (16B) for sealing the gap (G2) between the flange (14) and the cover (17).

Description

light sensor

The present invention relates to optical sensors.

Optical sensors such as photoelectric sensors and image sensors have a circuit board that constitutes the control unit, etc., built into the housing. A cable is connected to the circuit board through the housing in order to supply power from outside the housing to the circuit board and transmit signals processed by the circuit board to the outside of the housing (for example, Patent Documents 1 and 2). reference).

Japanese Patent Application Laid-Open No. 2007-3348 Japanese Patent Application Laid-Open No. 2020-150205

　In the assembly process of the optical sensor, the outer sheath of the cable is fixed to the housing and cannot be moved freely. If the strands of wire extending from the end of the outer cover are short, workability is poor when mounting the cable on the circuit board by soldering, which increases the burden on the operator. FIG. 2 of Patent Literature 1 discloses an optical sensor in which wires are extended long from the end of the outer skin to facilitate soldering. However, if the work is performed by extending the wires, a space is required to accommodate the long wires by folding them, which increases the size of the housing. Since optical sensors are often installed inside production lines and equipment in factories, compact housings are desired.

The optical sensor of Patent Document 2 has been proposed as an optical sensor that does not need to be soldered inside the housing. In Patent Document 2, a flexible board with a connector is preliminarily soldered to the tip of a cable, and in the process of assembling the optical sensor, the flexible board is elastically deformed to pass through the through hole, and the flexible board is attached to the connector of the circuit board. The cable is mounted on the circuit board by inserting the connector. According to Patent Document 2, although the burden on the operator is reduced, the manufacturing cost of the optical sensor increases because it is necessary to add an expensive flexible substrate and connector to the cable.

Therefore, an object of the present invention is to provide an optical sensor in which a cable can be mounted on a circuit board in a simple and space-saving manner.

An optical sensor according to an aspect of the present disclosure includes a housing in which a through hole is formed, a plurality of strands whose core wires are covered with an inner skin, a cable having an outer sheath that bundles the plurality of strands, and an end of the outer sheath. a flange integrally molded with the outer skin and the inner skin and formed to a size that can pass through the through-hole; a stopper that regulates the position of the flange with respect to the through-hole; a cover that covers a gap between the flange and the cover; a first sealing material that seals a gap between the outer surface of the housing and the cover; and a second sealing material that seals a gap between the flange and the cover.

A method for manufacturing an optical sensor according to an embodiment of the present disclosure includes: accommodating a circuit board in a housing in which a through hole is formed; preparing a cable having a flange dimensioned to be able to pass through the through-hole, inserting the flange into the through-hole deeper than the predetermined position at the time of completion, and soldering the core wire of the cable to the circuit board; The circuit board is accommodated in the housing, the through-hole and the flange are arranged in a predetermined position, the stopper is attached and positioned, and the sealing material and the cover are attached to seal the boundary between the through-hole and the flange. includes doing.

According to these aspects, since the cable can pass through the through-hole, the cable and the circuit board are soldered while the cable is inserted deeper than the predetermined position at the time of completion, so that the burden on the operator can be reduced. . Since there is no need to work by extending the wire from the outer cover, the housing can be made compact by omitting the space for folding and accommodating the wire. Since a stopper is provided to regulate the position of the flange with respect to the through hole, the housing and cable can be positioned even after soldering. Further, the housing and the flange are in close contact with the stopper, and the inner skin and the outer skin are integrally molded with the flange and are in close contact with each other. Since it is provided with a material and a cover, it is possible to fully satisfy the design requirements for the cable root, such as tensile resistance, bending resistance, and sealing performance. Since the optical sensor can be configured with inexpensive parts, the manufacturing cost of the optical sensor can be suppressed.

In the above aspect, a light source that emits light may be further provided, the flange may be made of translucent resin, and the light from the light source may be reflected by the stopper to enter the flange.

According to this aspect, if the light source is mounted on the circuit board or the like, the translucent flange into which the light is incident can be lit or blinked. The flange can be used as an indicator to show the operational status of the optical sensor.

In the above aspect, a twin ring is provided in which the second O-ring and the first O-ring surrounding the second O-ring are integrally formed, the first sealing material is the first O-ring, and the second The sealing material may be the inner second O-ring.

According to this aspect, since the first sealing material and the second sealing material are integrally molded, the burden on the operator can be reduced in the assembly process compared to positioning them individually.

In the above aspect, a first groove is formed in the outer peripheral surface of the flange, a second groove is formed in the through-hole at a position corresponding to the first groove, and the stopper includes the first groove and the second groove. It may be a sheet metal inserted across the

According to this aspect, the stopper can be configured with inexpensive parts. The manufacturing cost of the optical sensor can be suppressed.

According to the present invention, it is possible to provide an optical sensor in which a cable can be easily mounted on a circuit board while saving space.

FIG. 1 is a cross-sectional view showing the internal structure of an optical sensor according to one embodiment of the present invention. FIG. 2 is a partially exploded perspective view of the optical sensor shown in FIG. 1, viewed from the through hole side. 3 is a cross-sectional view showing an enlarged root of the cable shown in FIG. 1. FIG. FIG. 4 is a sectional view showing a state in which the stopper shown in FIG. 3 is removed and the cable is inserted deeper than the predetermined position. FIG. 5 is a cross-sectional view taken along line VV in FIG. FIG. 6 is a diagram showing an example of a procedure for manufacturing a photosensor according to one embodiment of the present invention.

A preferred embodiment of the present invention will be described with reference to the accompanying drawings. It should be noted that, in each figure, the same reference numerals have the same or similar configurations. Hereinafter, each configuration will be described in detail with reference to the drawings. FIGS. 1 and 2 disclose a photoelectric sensor provided with a light projecting portion 4 for emitting light and a light receiving portion 5 for receiving light as an example of the optical sensor 1. FIG. The amount of light reaching the light receiving section 5 changes when the projected light is blocked or reflected by the workpiece. The photoelectric sensor can detect this change, convert it into an electric signal, and output it to an external device.

However, the optical sensor 1 is not limited to a photoelectric sensor. The optical sensor 1 may be a displacement sensor that measures the distance from the sensor to the object by detecting the amount of physical change in the object with an optical element and calculating the amount of change as a distance, or by using a camera. It may be an image sensor that calculates the area, center of gravity, length, position, etc. of the object by image processing the captured image and outputs data and judgment results, or reads barcodes and two-dimensional codes. It may be a code reader.

FIG. 1 is a cross-sectional view showing the internal structure of an optical sensor 1 according to one embodiment of the present invention. In the illustrated example, the optical sensor 1 is configured as a retroreflective photoelectric sensor, and in addition to the light projecting unit 4 and the light receiving unit 5, includes an amplifier unit, a control unit, etc. (not shown). 10, it is connected to an external power source and an external device. The optical sensor 1 may be configured as a transmissive photoelectric sensor, and the light projecting section 4 and the light receiving section 5 may be accommodated in separate housings 2, respectively. It may be configured as an amplifier-separated photoelectric sensor in which the amplifying section is separated outside the housing 2 , or may be configured as a power-source photoelectric sensor in which the power section is built in the housing 2 .

The amplifier section, control section, etc. described above are mounted on the circuit board 3 housed in the housing 2 . The circuit board 3 may further comprise an indicator light source 6 for indicating the operating state of the optical sensor 1 . A base end of a cable 10 is mounted by soldering in a mounting area 7 defined by the circuit board 3 . A connector 8 that can be connected to an external power source or a connector of an external device may be provided at the tip of the cable 10 . The housing 2 is made of a metal material such as stainless steel or zinc die-cast, except for

windows

4W and 5W in which the light projecting section 4 and the light receiving section 5 are provided. However, the material of the housing 2 is not limited to the metal material. For example, the housing 2 may be formed from a resin material such as polybutylene terephthalate resin or ABS resin. The

windows

4W and 5W are made of, for example, a translucent material such as methacrylic resin or glass.

FIG. 2 is a partially exploded perspective view of the optical sensor 1 shown in FIG. 1 as seen from the through hole 9 side. As shown in FIG. 2 , the housing 2 includes a case body 20 formed in a substantially rectangular parallelepiped cup shape, and a lid 21 that covers the opening of the case body 20 . The case body 20 includes a bottom wall 22 and a peripheral wall 23 rising from the bottom wall 22 and extending toward the lid 21 . In the housing 2 , the bottom wall 22 is located on the opposite side of the lid 21 .

In the illustrated example, a circular through hole 9 is formed in the peripheral wall 23 . A cable 10 is inserted through the through hole 9 . The cable 10 includes a plurality of strands (11, 12), an outer sheath 13 that bundles the plurality of strands (11, 12), a flange 14 that integrally forms the outer sheath 13 and the inner sheath 12 at the end of the sheath 13, have. The strands (11, 12) have a core wire 11 made up of a plurality of conducting wires and an inner skin 12 covering the core wire 11. - 特許庁The inner skin 12 and the outer skin 13 are made of vinyl chloride resin, for example.

The flange 14 is made of a resin material such as polybutylene terephthalate resin or ABS resin. Flange 14 may be formed from a translucent material. The translucent material may be transparent or milky white. In that case, the light from the light source 6 (shown in FIG. 1) mounted on the circuit board 3 or the like may be reflected by the stopper 15 formed of sheet metal or the like and incident on the flange 14 . When the flange 14 is made of translucent resin, the flange 14 can be used as an indicator for displaying the operating state of the optical sensor 1 .

The flange 14 is formed in a cylindrical shape having substantially the same cross section as the through hole 9 . The aforementioned through hole 9 may have a shape other than circular. For example, the through hole 9 may be substantially D-shaped or oval. In that case, the flange 14 has a substantially D-shaped (D-cut) or elliptical cross section. If the through hole 9 is formed in a shape other than circular, the flange 14 can be configured so as not to rotate with respect to the through hole 9 .

FIG. 3 is a cross-sectional view showing an enlarged root of the cable 10 shown in FIG. As shown in FIG. 3 , the flange 14 integrally forming the outer skin 13 and the inner skin 12 is formed to have dimensions that allow it to pass through the through hole 9 . A portion of the flange 14 protruding outward from the housing 2 is formed into a reduced diameter portion 19 having a smaller diameter than other portions. A step surface formed by a step between the diameter-reduced portion 19 and other portions is flush with the end surface of the through hole 9 . At the root of the cable 10, the optical sensor 1 further comprises a stopper 15, a cover 17, and first and

second sealing members

16A, 16B.

The stopper 15 regulates the position P0 of the flange 14 with respect to the through hole 9. A first groove 18 is formed on the outer peripheral surface of the flange 14 , and a second groove 28 is formed on the inner peripheral surface of the through hole 9 at a position corresponding to the first groove 18 . The stopper 15 is formed, for example, from sheet metal in a substantially C shape (see FIG. 2), and is inserted across the first groove 18 and the second groove 28 . Note that the configuration of the stopper 15 is not particularly limited, and other configurations may be used.

The cover 17 is made of the same material as the housing 2 and covers the boundary portion B between the inner peripheral surface of the through hole 9 and the outer peripheral surface of the flange 14 . As shown in FIG. 2, the cover 17 has a substantially rectangular flat plate shape with a through hole in the center, and is fixed to the outer surface 2B of the housing 2 with tightening screws 17S or the like. The reduced diameter portion 19 of the flange 14 is inserted into the through hole of the cover 17 .

As shown in FIG. 3, the first sealing material 16A seals the gap G1 between the outer surface 2B of the housing 2 and the inner surface of the cover 17. The second sealing member 16B seals the gap G2 between the outer end surface of the flange 14 and the inner surface of the cover 17. As shown in FIG. In the illustrated example, the first and

second seals

16A, 16B are the second O-ring 16B and the first O-ring 16A surrounding (circumscribing the second O-ring 16B) the second O-ring 16B. It is composed of a twin ring 16 integrally formed with. The sealing material is not limited to the illustrated example, and may be other types of sealing material. For example, the gaps G1 and G2 may be sealed with two separable large and small O-rings. The twin ring 16 is arranged across the step surface of the flange 14 and the end surface of the through hole 9 .

Next, a procedure for manufacturing the optical sensor 1 will be described with reference to FIGS. 4 to 6. FIG. FIG. 4 is a cross-sectional view showing a state in which the stopper 15 shown in FIG. 3 is removed and the cable 10 is inserted to a position P1 deeper than the predetermined position P0, and FIG. 1 is a cross-sectional view along a line; FIG. As shown in FIGS. 4 and 5, the flange 14 is configured to be able to pass through the through hole 9 when the stopper 15 is removed.

Therefore, the assembly work can be performed by bringing the tip of the cable 10 close to the mounting area 7 of the circuit board 3 to the position P1 where soldering is easy. After mounting the cable 10 on the circuit board 3 by soldering, the cable 10 can be attached to the housing 2 by placing the flange 14 at a predetermined position P0 in the completed state of the optical sensor 1 and attaching the stopper 15 to the flange 14. can be fixed to

FIG. 6 is a diagram showing an example of the procedure for manufacturing the optical sensor 1. FIG. A cable 10 having a flange 14 in which an inner skin 12 and an outer skin 13 of the cable 10 are integrally formed is prepared. The dimensions of the cross section of the flange 14 are formed so as to pass through the through hole 9 formed in the housing 2 (step S1).

Next, the flange 14 is inserted into the through hole 9 from the outer surface 2B side of the housing 2 to a position P1 deeper than the predetermined position P0 at the time of completion, and the core wire 11 of the cable 10 inserted through the through hole 9 is inserted into the housing. The core wire 11 of the cable 10 is soldered to the mounting area 7 of the circuit board 3 in a state of being pulled out of the body 2 (step S2). Since the soldering work can be performed in a state in which the core wire 11 can be freely moved, the burden on the worker can be reduced. The circuit board 3 to which the core wire 11 of the cable 10 is soldered is housed in the housing 2 (step S3).

Then, the through hole 9 and the flange 14 are arranged at a predetermined position P1, and the stopper 15 is attached to position the housing 2 and the cable 10 (step S4). Place the twin ring 16 on the outer surface 2B of the housing 2 while visually confirming the position thereof, attach the cover 17 so as to press the twin ring 16, and seal the boundary portion B between the through hole 9 and the flange 14 (step S5). ). Thereby, the cable 10 is fixed to the housing 2, and the inside and outside of the housing 2 are sealed.

According to the optical sensor 1 of the present embodiment configured as described above, since the cable 10 and the circuit board 3 are soldered in a state where the cable 10 is inserted deeper than the predetermined position P0 at the time of completion, work is required. It can reduce the burden on people. Since there is no need for a space next to the mounting area 7 to accommodate the folded wires 11, the housing 2 can be made compact. The housing and the flange are in close contact with the stopper, the inner skin and the outer skin are integrally molded with the flange, and the first sealing material, the second sealing material, and the second sealing material for sealing the boundary between the through hole and the flange Since the cover is provided, it is possible to sufficiently satisfy the design requirements for the cable root, such as tensile resistance, bending resistance, sealing performance, and the like. Since the root portion of the cable 10 can be configured with inexpensive parts such as sheet metal, the manufacturing cost of the optical sensor can be suppressed.

The embodiments described above are for facilitating understanding of the present invention, and are not intended to limit and interpret the present invention. Each element included in the embodiment and its arrangement, materials, conditions, shape, size, etc. are not limited to those illustrated and can be changed as appropriate. Also, it is possible to partially replace or combine the configurations shown in different embodiments.

[Appendix 1]
A housing (2) in which a through hole (9) is formed;
A cable (10) having a plurality of strands (11, 12) in which a core wire (11) is covered with an inner sheath (12), and an outer sheath (13) bundling the plurality of strands (11, 12);
a flange (14) formed integrally with the outer skin (13) and the inner skin (12) at the end of the outer skin (13) and having a dimension that allows passage through the through hole (9);
a stopper (15) that regulates the position (P0) of the flange (14) with respect to the through hole (9);
a cover (17) fixed to the outer surface (2B) of the housing (2) and covering a boundary (B) between the through hole (9) and the flange (14);
a first sealing material (16A) for sealing a gap (G1) between the outer surface (2B) of the housing (2) and the cover (17);
A second sealing material (16B) that seals the gap (G2) between the flange and the cover,
Optical sensor (1).

[Appendix 2]
A flange (14) in which the inner skin (12) and the outer skin (13) are integrally molded, and has a dimension that allows the flange (14) to pass through a through hole (9) formed in the housing (2). preparing a cable (10) (S1);
The flange (14) is inserted into the through hole (9) to a depth (P1) beyond the predetermined position (P0) at the time of completion, and the core wire (11) of the cable (10) is attached to the circuit board (3). soldering (S2),
housing the circuit board (3) in the housing (2) (S3);
Arranging the through-hole (9) and the flange (14) at the predetermined position (P0) and attaching a stopper (15) for positioning (S4);
Attaching sealing materials (16A, 16B) and a cover (17) to seal the boundary (B) between the through hole (9) and the flange (14) (S5);
A method for manufacturing an optical sensor (1).

DESCRIPTION OF SYMBOLS 1... Optical sensor, 2... Housing, 2A... Inner surface, 2B... Outer surface, 3... Circuit board, 4... Light projecting part, 5... Light receiving part, 4W, 5W... Window part, 6... Light source, 7... Mounting area, 8 Connector 9 Through hole 10 Cable 11 Core wire 12 Inner skin 13 Outer skin 14 Flange 15 Stopper 16 Twin ring 16A First seal 16B Second seal Material 17 Cover 17S Clamping screw 18 First groove 19 Reduced diameter portion 20 Case body 21 Lid 22 Bottom wall 23 Peripheral wall 28 Second groove B Boundaries, G1, G2, Gap, P0, P1, Position, S1 to S5, Optical sensor manufacturing method.

Claims

a housing in which a through hole is formed;
A cable having a plurality of strands in which a core wire is covered with an inner skin and an outer sheath that bundles the plurality of strands;
a flange that integrally molds the outer skin and the inner skin at the end of the outer skin and is formed to have dimensions that allow passage through the through hole;
a stopper that regulates the position of the flange with respect to the through hole;
a cover fixed to the outer surface of the housing and covering a boundary between the through hole and the flange;
a first sealing material that seals a gap between the outer surface of the housing and the cover;
a second sealing material that seals a gap between the flange and the cover,
light sensor.
further comprising a light source for emitting light,
The flange is made of translucent resin,
configured such that light from the light source is reflected by the stopper and enters the flange;
The optical sensor of claim 1.
A twin ring in which a second O-ring and a first O-ring surrounding the second O-ring are integrally formed,
The first sealing material is the first O-ring, and the second sealing material is the second O-ring,
3. The optical sensor according to claim 1 or 2.
A first groove is formed on the outer peripheral surface of the flange, and a second groove is formed in the through hole at a position corresponding to the first groove,
The stopper is a sheet metal inserted across the first groove and the second groove,
4. The optical sensor according to any one of claims 1-3.
Preparing a cable having a flange in which an inner skin and an outer skin are integrally molded and having a dimension that allows the flange to pass through a through hole formed in a housing;
inserting the flange deeper into the through hole than a predetermined position at the time of completion, and soldering the core wire of the cable to the circuit board;
housing the circuit board within the housing;
arranging the through-hole and the flange at the predetermined position and attaching a stopper for positioning;
installing a sealant and cover to seal the interface between the through hole and the flange;
A method for manufacturing an optical sensor.