JP3782489B2 - Surface mount photo reflector and photo interrupter - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a photo reflector and a photo interrupter that detect the passage or approach of an object in a non-contact manner.
[0002]
[Prior art]
Conventional surface mount photoreflectors and photointerrupters are shown in FIGS. 12 and 13, respectively. That is, as shown in FIG. 12, the photoreflector is made of glass epoxy in which first and second electrode patterns 2 and 4 including a pair of electrode patterns 2a, 2b, 4a and 4b arranged in a line are formed on the surface. A substrate 6, a light-emitting diode (hereinafter abbreviated as “LED”) 8 and a phototransistor 10 that are die-bonded to the electrode patterns 2 a and 4 a and wire-bonded to the electrode patterns 2 b and 4 b, respectively. A mold frame 12 that opens and surrounds the LED 8 and the phototransistor 10 except for a necessary direction and shields light, and a light-transmitting material such as epoxy or silicon that fills the mold frame 12 and seals the LED 8 and the phototransistor 10 And resin 14.
[0003]
As shown in FIG. 13, the photo interrupter is a phototransistor die bonded to each pair of lead frames 16 to 22 and one of the lead frames 16 and 20 and wire bonded to the other lead frames 18 and 22, respectively. 24 and the LED 26, epoxy resins 28 and 30 for sealing them, and a housing 32 made of plastic for sealing and fixing the sealed phototransistor 24 and the LED 26 so that they face each other. It was.
[0004]
[Problems to be solved by the invention]
In the conventional photoreflector and photointerrupter described above, the mold frame 12 is mounted on the substrate 6 for light shielding, and the lead frames 16 to 22 and the casing 32 are used for positioning and the like, so that the size and thickness are reduced. There was a problem that it was difficult to make it.
[0005]
Further, in the conventional photo reflector and photo interrupter, after the LEDs 8 and 26 and the phototransistors 10 and 24 are mounted on the substrate 6 and the lead frames 16 to 22, they are attached to the mold frame 12 or inserted and fixed to the housing 32. Therefore, there is a problem that the manufacturing and assembly processes increase.
[0006]
Further, since the LEDs 8 and 26 and the phototransistors 10 and 24 are wire-bonded to the electrode patterns 2b and 4b and the lead frames 18 and 22, when sealing with the translucent resin 14 and the epoxy resins 28 and 30, May break. In addition, the translucent resin 14 and the epoxy resins 28 and 30 expand due to heat when reflow soldering the photo reflector and the photo interrupter, and the wire may be disconnected due to the stress stress.
[0007]
In addition, the conventional photo reflector and photo interrupter have a structure in which light is emitted or received through the translucent resin 14 and the epoxy resins 28 and 30. Since the translucent resin 14 and the epoxy resins 28 and 30 are easily attached with dust and dust, the optical coupling characteristics may be hindered. Further, the translucent resin 14 and the epoxy resins 28 and 30 are formed relatively thick to protect the wires attached to the upper electrodes of the LEDs 8 and 26 and the phototransistors 10 and 24. For this reason, there also existed the subject that the efficiency of light emission and light reception fell.
[0008]
The present invention has been made in view of the problems of the above-described conventional example, and an object thereof is to provide a highly reliable surface-mount photoreflector and photointerrupter that can be reduced in size and thickness, and has high production efficiency. It is in.
[0009]
[Means for Solving the Problems]
The surface-mounted photo reflector of the present invention has a first mounting portion having a translucent bottom portion provided at the protruding end, with the front surface side having a convex shape and a back surface side having a concave shape by protruding to the front surface side, A second mounting portion that protrudes to the front surface side and has a convex shape on the front surface side and a concave shape on the back surface side, and a bottom portion provided at the protruding end has translucency and is arranged in parallel with the first mounting portion; And a substrate on which the first and second electrode patterns are formed on the back surface so as to correspond to the first and second attachment portions, and the first electrode is attached to the bottom portion of the first attachment portion. A light emitting element electrically connected to the pattern, a light receiving element attached to the bottom of the second attachment portion and electrically connected to the second electrode pattern, and a synthetic resin covering each of the light emitting element and the light receiving element It consists of.
[0010]
Further, the surface mount type photo interrupter of the present invention has a first mounting portion that protrudes to the front surface side so that the front surface side has a convex shape and the back surface side has a concave shape, and the bottom portion provided at the protruding end has translucency. And the bottom side provided at the protruding end has translucency and is provided at a predetermined interval in the first mounting part by projecting to the front side and forming the convex side on the front side and the concave side on the back side. A second mounting portion, and a substrate on which the first and second electrode patterns are formed on the back surface so as to correspond to the first and second mounting portions, and is attached to the bottom of the first mounting portion. A light emitting element electrically connected to the first electrode pattern, a light receiving element attached to the bottom of the second attachment portion and electrically connected to the second electrode pattern, and the light emitting element and the light receiving element Synthetic resin covering each of the above and the light emission A support member child and the light receiving element is supported by bending the substrate so as to face, it is made of.
[0011]
[Action]
In the surface mount photo reflector and the photo interrupter of the present invention, the substrate is provided with the first and second mounting portions, and the LED and the phototransistor are mounted and accommodated in the first and second mounting portions. For this reason, it is not necessary to use a mold frame, a lead frame, a casing, or the like in the conventional example, so that the thickness and size can be reduced, and the manufacturing process can be reduced.
[0012]
The surface mount photo reflector and photo interrupter of the present invention are configured to emit light or receive light through the bottoms of the first and second mounting portions of the substrate, thereby improving the optical coupling characteristics. It is.
[0013]
【Example】
FIG. 1 is a perspective view showing a surface mount photo reflector according to an embodiment of the present invention. Reference numeral 40 denotes a substrate made of an insulating material having translucency and heat resistance. The board | substrate 40 in a present Example is comprised with the thermoplastic polyimide film, and has the thickness of 0.1-several mm. The substrate 40 is provided with first and second mounting portions 40a, 40b arranged in parallel so that the front side protrudes convexly and the back side is concave. In addition, first and second electrode patterns 42 and 44 are provided on the back side of the substrate 40. The first and second electrode patterns 42 and 44 include a pair of electrode patterns 42a, 42b, 44a, and 44b. The first and second electrode patterns 42 to 44 are provided from the through-hole electrode portions 46 to 52 provided at the four corners of the substrate 40, respectively. 2 It is formed over the bottom portions 40c and 40d of the mounting portions 40a and 40b.
[0014]
Reference numeral 54 denotes a light emitting element composed of an LED whose back surface 54a is fixed to the back surface side of the bottom 40c of the first mounting portion 40a of the substrate 40. As shown in FIG. 2, the light-emitting element 54 in this embodiment is a cube or a rectangular parallelepiped, and has electrodes 54d and 54e on the side surfaces 54b and 54c near the back surface 54a, respectively. The electrodes 54d and 54e are electrically connected to the electrode patterns 42a and 42b of the first electrode pattern 42, respectively. The light-emitting element 54 has the same structure as when the conventional LED 8 having electrodes on the front and back surfaces as used in the photoreflector shown in FIG. It is configured to make.
[0015]
A light receiving element 56 includes a phototransistor having a back surface 56 a fixed to the back surface side of the bottom 40 d of the second mounting portion 40 b of the substrate 40. The conventional phototransistor 10 used in the photoreflector shown in FIG. 12 has electrodes on the front and back surfaces. As shown in FIG. 3, the light receiving element 56 in this embodiment is provided with an emitter electrode 56b and a collector electrode 56c on the back surface 56a. The emitter electrode 56b and the collector electrode 56c are electrically connected to the electrode patterns 44a and 44b of the second electrode pattern 44 when the back surface 56a is fixed to the bottom 40d of the second mounting portion 40b.
[0016]
58 and 60 are synthetic resins made of epoxy resin or the like that fill the first and second mounting portions 40a and 40b and cover and seal the light emitting element 54 and the light receiving element 56, respectively. The synthetic resins 58 and 60 in this embodiment are colored in a color that blocks or absorbs light, such as black, in order to limit the direction of light emission or light reception and prevent the influence of external light. In the case where the substrate 40 colored or shielded so that only the bottom portions 40c and 40d of the first and second mounting portions 40a and 40b are translucent is used, the synthetic resin 58 and 60 is transparent. Can also be used.
[0017]
The surface mount photoreflector having the above configuration is mounted by mounting on a mother board and fixing the through-hole electrodes 46 to 52 to the electrode pattern on the mother board with solder or the like. In this photoreflector, when light is supplied to the first electrode pattern 42, the light emitting element 54 emits light, and the light is irradiated upward in the figure through the bottom 40c of the first mounting portion 40a. Then, when the irradiated light is reflected by the object and the reflected light reaches the light receiving element 56 via the bottom 40d of the second mounting portion 40b, the light receiving element 56 becomes conductive, and from the second electrode pattern 44 Operates to output a signal.
[0018]
Next, a manufacturing process of the surface mount photo reflector will be described. First, hundreds to thousands of photo reflectors as shown in FIGS. 4 and 5 were formed by printing or etching copper on the back surface of the aggregate substrate 62 made of a thermoplastic polyimide film or the like that can be manufactured at the same time. The first and second electrode patterns 42 and 44 shown in FIG. 1 are formed in the region where each photoreflector is formed by plating gold, nickel or solder on the pattern or the copper foil pattern thus formed. To do.
[0019]
Thereafter, the first and second attachment portions 40a and 40b shown in FIG. 1 are formed in the region where each photoreflector is formed on the collective substrate 62 by heating press or injection molding.
[0020]
Next, as shown in FIGS. 6 and 7, the light-emitting element 54 and the light-receiving element 56 are die-bonded in the first and second mounting portions 40a and 40b of the collective substrate 62, respectively, and the electrodes 54d, 54e and the emitter electrode 56b and collector electrode 56c of the light receiving element 56 are fixed with high temperature solder or silver epoxy resin.
[0021]
Further, the first and second mounting portions 40a and 40b are filled with synthetic resins 58 and 60, and the light emitting element 54 and the light receiving element 56 are sealed.
[0022]
As described above, in order to emit and receive light only in the set direction, when sealing with synthetic resin 58, 60, it may be further sealed with infrared cut epoxy resin or light blocking insulator. good. In addition, by applying a light blocking resist or a copper foil pattern to the front surface or the back surface of the collective substrate 62 in advance, it is possible to reliably shield light other than the portion that transmits light.
[0023]
Finally, a line in the X and Y axis directions passing through the center of the through-hole electrode portion of the collective substrate 62 is cut by slicing or the like, and separated into individual photo reflectors.
[0024]
FIG. 8 is a perspective view showing a surface mount type photo interrupter according to an embodiment of the present invention, and FIG. 9 is a perspective view showing a state before attaching a support member of the photo interrupter shown in FIG. This photo interrupter has the same basic structure as the photo reflector shown in FIG. 1, and the material of each part is also the same. For this reason, the structure and manufacturing process will be described below with a focus on the differences from the photo reflector described above. The substrate 140 in this photo interrupt has an elongated rectangular shape, and includes three regions 140e to 140g on the left, right, and center. First and second attachment portions 140a and 140b similar to those of the photo reflector are formed in the left and right end regions 140e and 140g of the substrate 140, respectively. The first and second electrode patterns 142 and 144 formed on the back side of the substrate 140 and made up of a pair of electrode patterns 142a, 142b, 144a, and 144b are divided into left and right end regions 140e and 140g and a central region 140f. Are formed from the electrodes 146 to 152 provided on the back surface of the bent portion between the first and second mounting portions 140a and 140b to the bottom portions 140c and 140d. In this photo interrupter, concave portions 140h to 140k are provided on the side surfaces near the boundaries of the regions 140e to 140g of the substrate 140 for easy bending.
[0025]
A light emitting element 154 and a light receiving element 156 having the same structure as the light emitting element 54 and the light receiving element 56 of the photoreflector described above are mounted in the first and second mounting portions 140a and 140b of the substrate 140. These are sealed with synthetic resins 158 and 160 in the same manner as the photo reflector.
[0026]
The support member 170 shown in FIG. 8 supports the substrate 140 to which the light emitting element 154 and the light receiving element 156 are fixed and sealed as shown in FIG. 9 by bending the substrate 140 so that the light emitting element 154 and the light receiving element 156 face each other. Is to do. The support member 170 in this embodiment is formed by bending a plate-like member having the same size as that of the substrate 140 so as to form a U-shape with the upper portion opened in the figure, and is formed on the arm portions 170a and 170b at the left and right ends. Are formed with notches 170c and 170d that fit the first and second attachment portions 140a and 140b. The substrate 140 is bent and fixed along the outer surface of the support member 170. In this embodiment, a plurality of small protrusions 170e are provided on the outer surfaces of the arm portions 170a and 170b of the support member 170, and the small protrusions 170e are press-fitted into small holes provided in the substrate 140, whereby the substrate 140 is inserted into the support member 170. Is attached. In addition, the substrate 140 can be attached to the support member 170 by adhesion, pressure bonding, or the like.
[0027]
The photo interrupter having the above-described configuration is mounted by placing on the mother board and fixing the electrodes 146 to 152 provided on the back surface of the bent portion to the electrode pattern on the mother board with solder or the like. In this photo-interrupter, the power is supplied to the first electrode pattern 142 so that the light emitting element 154 emits light, and the light is irradiated in the direction of the light receiving element 156 facing through the bottom 140c of the first mounting portion 140a. The Then, when the irradiated light is blocked by the object and does not reach the light receiving element 156 via the bottom part 140d of the second mounting part 140b, the light receiving element 156 becomes non-conductive, and at this time, the second electrode pattern The passage of an object is detected from the signal output from 144.
[0028]
Further, the manufacturing process of the photo interrupter having the above-described configuration is almost the same as that of the above-described photo reflector. As shown in FIGS. 10 and 11, the first and second electrode patterns are formed on the large substrate 162 in the same manner as the photo reflector. 142, 144, first and second attachment portions 140a, 140b are formed, and similarly, a light emitting element 154 and a light receiving element 156 are attached and sealed with synthetic resins 158, 160, and each photo interrupter is attached to each photo interrupter. Separately, the product shown in FIG. 9 is manufactured. Thereafter, the substrate 140 is attached to the support member 170 to complete the photo interrupter.
[0029]
【The invention's effect】
According to the present invention, a mold frame, a lead frame, or a housing is not used, and the outer shape is formed by a plate-like or film-like substrate or the substrate and a plate-like support member. can do.
[0030]
Further, in the present invention, since the wire bonding process is not used, it is possible to prevent deterioration in quality due to defective wire bonding or the like, and it is possible to provide a highly reliable photo reflector and photo interrupter.
[0031]
Furthermore, large-scale substrates can be used for mass production, and mass productivity can be improved.
[0032]
In addition, it does not emit or receive light through a synthetic resin that easily adheres to dust, dust, etc., but it emits and receives light through a substrate that is less likely to adhere to dust and dust and is easy to remove. This can reduce the factors.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a surface mount photo reflector according to an embodiment of the present invention.
FIG. 2 is a perspective view showing the light emitting device shown in FIG.
3 is a perspective view showing the light receiving element shown in FIG. 1. FIG.
4 is a plan view showing a large-sized substrate for manufacturing the surface-mounted photo reflector shown in FIG. 1. FIG.
5 is a cross-sectional view of the large substrate shown in FIG.
6 is a partially enlarged plan view showing a state in which a light-emitting element and a light-receiving element are attached to the large-sized substrate shown in FIG.
7 is a cross-sectional view showing a state in which the large substrate shown in FIG. 6 is filled with a synthetic resin.
FIG. 8 is a perspective view showing a surface-mount photo interrupter according to an embodiment of the present invention.
9 is a perspective view showing a state before the support member of the photo interrupter shown in FIG. 8 is attached. FIG.
10 is a partially enlarged plan view showing a state in which a light emitting element and a light receiving element are attached to a large-sized substrate for manufacturing the surface mount type photo interrupter shown in FIG. 8;
11 is a cross-sectional view illustrating a state in which the large substrate illustrated in FIG. 10 is filled with a synthetic resin.
FIG. 12 is a perspective view showing a conventional photo reflector.
FIG. 13 is a perspective view showing a conventional photo interrupter.
[Explanation of symbols]
40, 140 Substrate 40a, 140a First mounting portion 40b, 140b Second mounting portion 42, 142 First electrode pattern 44, 144 Second electrode pattern 54, 154 Light emitting element 56, 156 Light receiving element 58, 60, 158, 160 Composition Resin 170 support member

Claims (4)

By projecting to the front side, the front side has a convex shape and the back side has a concave shape, and the bottom part provided at the projecting end has a translucent first mounting part and the front side projects by projecting to the front side. And the bottom surface provided at the protruding end has a light transmitting property and has a second mounting portion arranged in parallel with the first mounting portion, and the first and second A substrate on which the first and second electrode patterns are formed on the back surface so as to correspond to the attachment portions,
A light emitting device attached to the bottom of the first attachment portion and electrically connected to the first electrode pattern;
A light receiving element attached to the bottom of the second attachment part and electrically connected to the second electrode pattern;
A synthetic resin covering each of the light emitting element and the light receiving element;
A surface-mounted photo reflector characterized by comprising: Forming a plurality of first and second electrode patterns on the back surface of the light-transmitting aggregate substrate;
The collective substrate is formed with a concave shape and protrudes to the front surface side so that the front surface side has a convex shape and the back surface side has a concave shape. A step of forming a plurality of second mounting portions arranged in parallel to the first mounting portion, the bottom side being formed in the protruding end and the bottom surface being formed in a concave shape on the front surface side is convex ,
Attaching a light emitting element and a light receiving element to the bottom of the first and second attachment parts, respectively, and electrically connecting to the first and second electrode patterns, respectively;
Sealing the light emitting element and the light receiving element with a synthetic resin;
Cutting the aggregate substrate and separating it into photo reflectors;
A method for manufacturing a surface-mounted photo reflector, comprising: By projecting to the front side, the front side has a convex shape and the back side has a concave shape, and the bottom part provided at the projecting end has a translucent first mounting part and the front side projects by projecting to the front side. The bottom surface provided at the projecting end has translucency and has a second attachment part provided at a predetermined interval from the first attachment part, the first attachment part having a concave shape on the back side . And a substrate on which the first and second electrode patterns are formed on the back surface so as to correspond to the second mounting portion, and
A light emitting device attached to the bottom of the first attachment portion and electrically connected to the first electrode pattern;
A light receiving element attached to the bottom of the second attachment part and electrically connected to the second electrode pattern;
A synthetic resin covering each of the light emitting element and the light receiving element;
A support member that bends and supports the substrate so that the light emitting element and the light receiving element face each other;
A surface-mount photointerrupter characterized by comprising: Forming a plurality of first and second electrode patterns on the back surface of the light-transmitting aggregate substrate;
The collective substrate is formed with a concave shape and protrudes to the front surface side so that the front surface side has a convex shape and the back surface side has a concave shape. A step of providing a plurality of second mounting portions having a convex shape on the front surface side and a concave shape on the back surface side, a bottom portion formed at the protruding end thereof, and provided at a predetermined interval in the first mounting portion ;
Attaching a light emitting element and a light receiving element to the bottom of the first and second attachment parts, respectively, and electrically connecting to the first and second electrode patterns, respectively;
Sealing the light emitting element and the light receiving element with a synthetic resin;
Cutting the collective substrate so that the light emitting element and the light receiving element each form a pair;
Bending the cut substrate and fixing it to the support member;
A method for manufacturing a surface-mounted photointerrupter, comprising:

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