JPH0749814Y2 - Optical coupling device for sphere detection - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an optical coupling device, and relates to a transmissive optical coupling device (photointerrupter) that detects passage of an object to be detected such as a pachinko ball.

<Prior Art> Conventional pachinko ball passing detectors include a magnetic type shown in FIG. 10 (hereinafter referred to as prior art 1) and an optical type shown in FIG. 11 (hereinafter referred to as prior art 2). .

[Prior Art 1] The magnetic pachinko ball passage detector shown in FIG. 10 includes a pachinko ball passage hole 1 and a magnetic coil 2 mounted on the inner wall of the passage hole 1. Then, the passage of the pachinko ball is detected without contact by detecting the change in the magnetic field of the magnetic coil 2 when the pachinko ball passes through the passage hole 1.

[Prior Art 2] The optical pachinko ball passage detector shown in FIG. 11 is a transmissive optical coupling device (photointerrupter), and includes a light emitting element 4 and a light emitting element 4 and a passage 5 in the device body 3. The light receiving elements 6 that are arranged so as to face each other in between are housed so as to be optically coupled. Then, when the pachinko balls pass through the passage 5, the pachinko balls block the optical path formed on the passage 5 to detect the passage of the pachinko balls without contact.

In FIGS. 10 and 11, 7 is a printed wiring board (PWB), and 8 is
Is an electronic component, 9a is a light projecting window, and 9b is a daylighting window.

<Problems to be Solved by the Invention> However, the following problems have been pointed out in the above-mentioned conventional techniques.

(1) In the related art 1, since the change of the magnetic field of the magnetic coil 2 at the time of passing the pachinko ball is detected to detect the passing of the punch ball, malfunction occurs due to electromagnetic noise due to the communication radio wave.

(2) Since the prior art 2 is a non-light modulation system or an asynchronous type even in a light modulation system, it is weak against ambient light noise and malfunctions due to intrusion of ambient light noise.

(3) Further, in the prior art 2, even if it is the synchronous type of the light modulation method, the device body (holder) 3 is formed in a U-shape, and each lead terminal of the light emitting element 4 and the light receiving element 6 is formed. Since it is drawn out in the direction orthogonal to the optical path, it becomes thicker and larger, and it cannot be made thinner and smaller than the magnetic type shown in FIG.

In view of the above, the present invention has an object to provide an optical coupling device capable of preventing a malfunction at the time of detecting a detection object which is a sphere and realizing a thin and small size.

<Means for Solving the Problems> The means for solving the problems according to the present invention is, as shown in FIGS. 1 to 4, housed in a device body 11 so that a light emitting element 12 and a light receiving element 13 are optically coupled. In the optical coupling device for detecting the presence or absence of passage of the sphere 10 which is the object to be detected without contact, the light emitting element 12 is pulse-driven and the light receiving element 13 is synchronized with this drive to pass the sphere 10. The light modulation synchronous drive circuit 14 for detecting the presence or absence of the through hole, the passage hole 15 penetrating the device body 11 for passing the spheres 10 one by one, and the passage direction orthogonal to the passage direction of the sphere 10. A wiring board having lead terminals 12a, 12b, 13a, 13b, 13c, 13d arranged in parallel and mounted with the light emitting element 12 and the light receiving element 13 from which the lead terminals 12a, 12b, 13a, 13b, 13c, 13d are drawn out. 17 and a first guiding light from the light emitting element 12 to the passage hole 15. The light guide part (41) and the second light guide part (42) for guiding the light from the first light guide part (41) to the light receiving element (13) are provided. With the passage hole side end of the portion 42,
The optical axis A connecting the both ends is arranged so as to deviate from the center of the passage hole 15.

<Operation> In the above means for solving problems, when the sphere 10 does not pass through the passage hole 15, the light emitted from the light emitting element 12 is the first light guide portion 41.
The light is guided to the passage hole 15 through the second light guide portion 42, is received by the light receiving element 13 through the second light guide portion 42, and outputs a signal without a sphere.

When the sphere 10 is passing through the passage hole 15, the sphere 10
Thus, the light emitted from the light emitting element 12 is blocked and does not reach the light receiving element 13. Therefore, a signal indicating that there is a sphere is output.

At this time, since the light modulation synchronous drive circuit 14 is provided, the light emitting element 12 can be pulse-driven, and the light receiving element 13 can be synchronized with this drive to detect whether or not the sphere 10 has passed, and disturbance light noise, etc. The incident frequency is different from the frequency detected by the light receiving element 13, so that no malfunction occurs.

Further, since the optical axis A in the passage hole 15 is deviated from the center of the passage hole 15, even when the two spheres 10 are in contact with each other and pass through substantially the center of the passage hole 15, a gap between the spheres 10 is generated. Light does not pass, and the two spheres 10 are not mistakenly detected as one.

<Embodiment> An embodiment of the present invention will be described below with reference to FIGS. 1 to 6.

FIG. 1 is a cross-sectional plan view of an optical coupling device showing an embodiment of the present invention, FIG. 2 is a vertical side view of the same, FIG. 3 is a plan view of the same, and FIG. 4 is a light modulation type synchronous drive circuit. Circuit diagram, Fig. 5 is a diagram showing a state in which no pachinko balls have passed, No. 6
The figure is a diagram showing a state in which a pachinko ball is passing through the passage hole.

As shown in the figure, the transmission type optical coupling device (photo interrupter) of the present embodiment is a device for detecting the presence or absence of passage of the object to be detected (pachinko ball) 10 without contact, and in the device body 11,
The light emitting element 12 and the light receiving element 13 are housed so as to be optically coupled.

An optical modulation synchronous drive circuit 14 for detecting the presence or absence of passage of the object to be detected 10 by pulse-driving the light-emitting element 12 and synchronizing the light-receiving element 13 with this drive is provided in the device body 11. Passage hole 15 for passing detection object 10
And the light emitting element 12 and the light receiving element 13 are arranged in parallel, and the lead terminals of the light emitting element 12 and the light receiving element 13 are formed.
12a, 12b, 13a, 13b, 13c, 13d is pulled out in a direction orthogonal to the passing direction of the object 10 to be detected, the light emitting element 12 in the passage hole 15
An optical guide 39 for efficiently guiding the light from the light receiving element 13 to the light receiving element 13 is provided.

As shown in FIGS. 1 to 3, the device main body 11 is formed of a light-shielding resin in a box shape. The device body 11 has an outlet for passing the detected object 10 out of the device body 11 on the bottom surface, and the light emitting element 12, the light receiving element 13, and these optical elements 12, 13 and the electrical component 16 are mounted. The printed wiring board (PWB) 17 to be accommodated is provided with a storage portion 18 and an inlet for guiding the detected object 10 into the apparatus main body 11 at a position corresponding to the outlet, and the storage portion 18 is arranged from above. The lid portion 19 is configured to be closed, and the lid portion 19 is fixed to the storage portion 18 by screwing or the like. In FIGS. 1 and 3, 25 is a screw insertion hole.

The light emitting element 12, a light emitting diode is used,
The lead terminals 12a and 12b of the light emitting element 12 are, as shown in FIG.
It is connected to a predetermined position of the printed wiring board 17 by soldering.

The light receiving element 13 is a four-terminal type photodiode, and the lead terminals 13a, 13b, 13c, 13d of the light receiving element 13 are connected to predetermined positions of the printed wiring board 17 by soldering.

As shown in FIG. 4, the light modulation synchronous drive circuit 14 includes a light receiving element.
An oscillator 26 for pulse-driving the light-emitting element 12 and a synchronization detection circuit unit 27 for detecting whether the output signal of the light-receiving element 13 is synchronized with the pulse driving of the light-emitting element 12 are provided. And a demodulation circuit section 30 for demodulating the output signal of the light receiving element 13 which has been amplified and compared by the amplifier 28 and the comparator 29 arranged in the preceding stage of the synchronization detection circuit section 27, that is, modulated.
And a constant voltage circuit section 31. Further, the optical modulation synchronous drive circuit 14 has a signal processing function of determining the detection level for the first time in three consecutive cycles even if a pulse of the same frequency comes in. We are taking serious measures. In FIG. 4, 32 and 33 are transistors, 34 is an ammeter, 35 is a negative feedback resistor, 36 and 37 are capacitors, and 38 is a resistor.

The passage hole 15 is formed by fitting an optical guide 39 into the outlet of the storage portion 18 and the inlet of the lid portion 19.

As shown in FIG. 1, the optical guide 39 is a light emitting device.
An optical system that forms a detection optical path for detecting the presence or absence of passage of the object 10 to be detected together with 12 and the light receiving element 13 is provided so as to efficiently guide light from the light emitting element 12 to the light receiving element 13. It is made of light-sensitive resin.

The optical guide 39 includes an annular portion 40 forming the passage hole 15, an L-shaped first light guide portion 41 that guides light from the light emitting element 12 to the annular portion 40, and a first light guide portion from the annular portion 40. The second light guide section 42 guides the light guided from the section 41 to the light receiving element 13. The second light guide section 42 is arranged in phase with respect to the connection point between the first light guide section 41 and the annular section 40. That is, the optical axis A is arranged at a position separated from the axis B so that the optical axis A is formed by separating the axis B connecting the connection point and the center of the annular portion 40 by l. As a result, the optical system including the light emitting element 12, the light receiving element 13, and the optical guide 39 can continuously detect the passage of the object to be detected.

Further, at the end of the second light guide portion 42, a reflection surface 42a for reflecting the light from the light emitting element 12 and guiding the light to the light receiving element 13 arranged below the second light guide portion 42 is provided downward. It is formed to be inclined.

The optical coupling device is assembled as follows.

First, the detection object outlet is placed in the storage portion 18 of the apparatus main body 11 and the lid portion.
An entrance for the object to be detected is provided in advance in 19, and the light emitting element 12, the light receiving element 13, and the electronic component 16 are mounted on the printed wiring board 17, and these are housed in the housing portion 18.

Next, the lower end of the optical guide 39 is fitted into the outlet of the housing portion 18, and the upper end of the optical guide 39 is fitted into the inlet of the lid portion 19, and the lid portion 19 is fixed to the housing portion 18 by screwing or the like.

At this time, the passage hole 15 for the object to be detected is provided so as to penetrate the apparatus main body 11 by the optical guide 39, and the lead terminals 12 of the light emitting element 12 and the light receiving element 13 are provided.
Since the a, 12b, 13a, 13c, and 13d are drawn out in the direction orthogonal to the passing direction of the detected object 10, the device main body 11 can be made thin.

By the way, as shown in FIGS. 7 to 9, the optical guide 39
It is also possible to consider an example in which is composed of an annular portion 40 and a light guide portion 42 that guides light from the light emitting element 12 from the annular portion 40 to the light receiving element 13. However, in this example, the light emitting element 12 and the light receiving element 13 must be arranged to face each other with the passage hole 15 in between, and the shape of the printed wiring board 17 becomes complicated.

On the other hand, the optical guide 39 of the present embodiment has an annular portion 40 that forms the passage hole 15, an L-shaped first light guide portion 41 that guides light from the light emitting element 12 to the annular portion 40, and an annular portion. Since the light guide element 42 and the second light guide section 42 guide the light guided from the first light guide section 41 to the light receiving element 13, the light emitting element 12 and the light receiving element 13 can be arranged in parallel, and printed wiring can be provided. The shape of the substrate 17 can be simplified, and the device body 11 can be downsized.

With the above, the device itself can be made thinner and smaller than the magnetic type.

Next, the operation of detecting the presence or absence of passage of the detected object (pachinko ball) 10 of the optical coupling device will be described.

As shown in FIG. 5, when the detected object 10 does not pass through the passage hole 15, the light emitted from the light emitting element 12 is received by the light receiving element 13 and a signal indicating that the detected object 10 is absent is output.

Further, as shown in FIG. 6, when the detected object 10 passes through the passage hole 15, the light from the light emitting element 12 is blocked by the detected object 10 and does not reach the light receiving element 13. That is, when the detection optical path is blocked by the detected object 10, a signal indicating that the detected object 10 exists is output.

At this time, the light emitting element 12 is pulse-driven by the oscillator 26 of the optical modulation synchronous drive circuit 14 inside the light receiving element 13, and the amplifier 2
8. The output signal of the light receiving element 13 modulated by the comparator 29 is emitted by the synchronization detection circuit section 27 of the optical modulation synchronization drive circuit 14 as a light emitting element.
It is detected whether or not it is synchronized with 12 pulse driving, and demodulated by the demodulation circuit unit 30.

In this way, the light modulation synchronous drive circuit 14 pulse-drives the light-emitting element 12 and synchronizes the light-receiving element 13 with this drive to detect the presence or absence of passage of the object to be detected 10. Even if this happens, no malfunction occurs because the frequencies detected by the light receiving element 13 are different.

Further, the second light guide portion 42 of the optical guide 39 has an optical axis A separated by 1 from an axis B connecting the connection point between the first light guide portion 41 and the annular portion 40 and the center of the annular portion 40. The light from the light emitting element 12 is efficiently guided to the light receiving element 13, and the optical system including the light emitting element 12, the light receiving element 13 and the optical guide 39 continuously detects the detected object. Therefore, no malfunction occurs when continuously detecting the detected object.

It should be noted that the present invention is not limited to the above embodiments, and it goes without saying that many modifications and changes can be made to the above embodiments within the scope of the present invention.

<Effect of Device> As is apparent from the above description, according to the present invention, (1)
Since the light modulation synchronous drive circuit is provided, the light emitting element can be pulse-driven and the light receiving element can be synchronized with this drive to detect the presence or absence of passage of the sphere. Even if ambient light noise is incident, the light receiving element can be detected. Since it is different from the frequency detected at
It is possible to prevent malfunctions when detecting a sphere.

(2) Further, a light emitting element and a light receiving element, each having a through hole penetrating the apparatus main body and having lead terminals drawn out in a direction orthogonal to the passing direction of the sphere, are arranged in parallel, and these are the passing direction of the sphere. Since it is mounted on the wiring board arranged in the direction orthogonal to, the device body can be made smaller and thinner.

(3) Further, since the optical axis connecting the passage hole side end of the first light guide portion and the passage hole side end of the second light guide portion is deviated from the center of the passage hole, the spherical bodies are in continuous contact with each other. Even when passing through the passage hole, the spheres can be reliably detected one by one.

[Brief description of drawings]

FIG. 1 is a cross-sectional plan view of an optical coupling device showing an embodiment of the present invention, FIG. 2 is a vertical side view of the same, FIG. 3 is a plan view of the same, and FIG. 4 is a light modulation type synchronous drive circuit. Circuit diagram, Fig. 5 is a diagram showing a state in which no pachinko balls have passed, No. 6
The figure shows a state in which a pachinko ball is passing through a passage hole, FIGS. 7 to 9 show other proposed examples, FIG. 10 is a cross-sectional view showing prior art 1, and FIG. 11 is prior art. It is sectional drawing which shows 2. 10: Object to be detected, 11: Device body, 12: Light emitting element, 13: Light receiving element, 14: Light modulation synchronous drive circuit, 15: Passage hole, 39: Optical guide, 12a, 12b, 13a, 13b, 13c, 13d: Lead terminal.

Claims (1)

[Scope of utility model registration request] 1. An optical coupling device for detecting a sphere in which a light emitting element and a light receiving element are housed so as to be optically coupled to each other in a main body of the apparatus, and whether or not a sphere which is an object to be detected passes is detected without contact. An optical modulation synchronous drive circuit for pulse-driving the light-emitting element and synchronizing the light-receiving element with this drive to detect the presence or absence of passage of the sphere; and one sphere formed penetrating the apparatus main body. Passing holes to be passed and the light emitting element and the light receiving element whose lead terminals are drawn out in a direction orthogonal to the passing direction of the sphere are arranged in parallel and mounted, and are arranged in a direction orthogonal to the passing direction of the sphere. A wiring board; a first light guide section that guides light from the light emitting element to the passage hole; and a second light guide section that guides light from the first light guide section to the light receiving element. The passage hole side end of the light guide and the second guide The passage hole side end parts, optical coupling device for sphere detection, wherein the optical axis connecting the both end portions are arranged so as to deviate from a center of the passage hole.