JPH03112029A - Optical fiber type photoelectric switch - Google Patents

Abstract

PURPOSE:To input logical operation results of detected signals of multiple detecting sections to a light receiving section and reduce the installation space of the whole device by properly combining and arranging optical fibers and detecting sections connected to a light projecting section and the light receiving section. CONSTITUTION:The light from the light projecting section 11 of a photoelectric switch main body 10 to a light projecting optical fiber 21 is projected from tips of detecting sections 40 through separate optical fibers 22. The reflected light from an object M is again fed to the detecting section 40 and fed to the light receiving section 12 of the main body 10 through a light receiving optical fiber 32. When at least one of multiple detecting sections 40 detects the object M, the detected signal is inputted to the light receiving section 12 in OR connection.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an optical fiber type photoelectric switch, and more specifically, a light emitting element and a light receiving element are combined to detect the interruption or reflection of light by an object to be detected and switch the switch. The present invention relates to an optical fiber type photoelectric switch, which is one of the photoelectric switches that operate, in which an optical fiber is connected to a light emitting element and a light receiving element so that a detection section can be set at a position away from the light emitting element and the light receiving element.

[Conventional technology]

Photoelectric switches have features such as non-contact detection of the presence or absence of objects to be detected and reliable switch operation, and can be incorporated into control mechanisms for controlling various mechanical devices. It is being used. In particular, with optical fiber photoelectric switches, the detection section provided at the tip of the optical fiber can be installed in any position and orientation. They have come to be widely used because of their advantages, such as the fact that they do not require much space for installation, and that multiple photoelectric switches can be collected and managed in one place.

Figure 9 shows the external structure of a general optical fiber type photoelectric switch.The photoelectric switch main body 1 includes a light emitting element and a light receiving element, as well as a device that controls the light emitting element and the light receiving element and amplifies the detection signal. It incorporates an amplifier unit consisting of a control circuit that performs various functions. Photoelectric switch body 1
A light emitting optical fiber 2 and a light receiving optical fiber 3 are connected to each other, and a detection section 4 is provided at the tips of both fibers 2.3. The illustrated photoelectric switch is a reflective photoelectric switch, in which light is projected from the tip of the detection unit 4 into the detection target space, is reflected by the detection target, and the reflected light is received again by the detection unit 4. By doing so, it is activated by detecting the object to be detected. In addition to the reflective type shown in the figure, photoelectric switches have a light-emitting detection section and a light-receiving detection section arranged facing each other, so that an object to be detected blocks the optical path between the light-emitting detection section and the light-receiving detection section. There are also transmissive photoelectric switches that are activated by

When using an optical fiber type photoelectric switch such as the one described above, there are cases where it is desired to perform a switch operation based on the result of a combination of main detection forces in a plurality of detection sections. For example, when you want to operate the switch only when an object to be detected is detected by both of the two detection parts, or when you want to operate the switch when the object to be detected is detected by at least one of the two detection parts. etc. In other words, a plurality of detection units, that is, photoelectric switches, are
This is a case of ND connection or OR connection. In this way, when performing a switch operation based on the logical operation results of detections in multiple detectors, conventionally, multiple photoelectric switches corresponding to the number of detectors are lined up, and the detection output from each photoelectric switch is The switch was operated based on the result of logical operation processing of the signal using an appropriate electronic circuit.

FIG. 10 shows an example of a circuit in which a plurality of photoelectric switches are combined to output a logical operation result.
In figure fa) two photoelectric switches S8. The output from the output transistor t of S2 is OR-connected on the electric circuit C to switch the load P, and the first
In Figure 0 (bl), AND connections are made in the same way.

[Problem to be solved by the invention]

However, with the above-mentioned conventional technology, the number of photoelectric switch bodies 1 equal to the number of inputs for logical operations, that is, the number of detection units 4, is required, resulting in very high costs and the problem of requiring additional installation space. there were. Furthermore, an electric circuit for performing logical operations on the output from the photoelectric switch is also required. In the case of the AND circuit shown in Figure 10 (bl), the circuit current of one photoelectric switch Sl also flows to the output transistor of the other photoelectric switch S2, so care must be taken to the current capacity and voltage drop. In this case, there is a problem that the electrically connected photoelectric switches Sz, St are affected by each other, such as there is a limit to the number of photoelectric switches S,... that can be connected at the same time. Since the outputs from S1, . . . are subjected to electrical logical operations, there is also a problem that the response speed up to the final switch operation is delayed by the rise time of the photoelectric switch S1.

Therefore, as mentioned above, the object of this invention is to provide an optical fiber photoelectric switch that can perform logical operations on detection information from multiple detection units and output it, and the device can be made simple and compact while requiring less installation space. The objective is to provide something that does not take much time, operates reliably, and has a fast response speed.

[Means to solve the problem]

Among the optical fiber photoelectric switches of the present invention that solve the above problems, the optical fiber photoelectric switch according to claim 1 includes a photoelectric switch main body having a light emitter, a light receiver, and an amplifier unit, and a light emitter and a light receiver. A reflective optical fiber type photoelectric switch that includes connected optical fibers and a detection section provided at the tip of the optical fiber, and one detection section emits and receives light, with one set of two fibers each for the light emission section and the light reception section. A plurality of detection units are provided such that one end of each set of the plurality of optical fibers is connected to each other, and each other end of each set is connected to the same detection unit.

The optical fiber type photoelectric switch of the present invention includes a photoelectric switch main body that includes a light emitting part having a light emitting element, a light receiving part having a light receiving element, an amplifier unit that controls the light emitting element and the light receiving element, and amplifies a detection signal. and an optical fiber connected to the light emitting part and the light receiving part of the photoelectric switch body,
It consists of a detection part installed at the tip of an optical fiber, and the detection part has a light emitting optical fiber and a light receiving optical fiber lined up, and reflects the light emitted from the tip of the light emitting optical fiber on the object to be detected. It constitutes a so-called reflective photoelectric switch that receives the returned light at the tip of a light-receiving optical fiber. The basic structure of such a photoelectric switch, especially the structure of the photoelectric switch body, can be exactly the same as that of a normal optical fiber type photoelectric switch.

The present invention uses a combination structure of an optical fiber and a detection section to perform a logical operation on a detection signal, and inputs the result of the logical operation to the light receiving section of the photoelectric switch body. In the optical fiber, a plurality of light-emitting optical fibers are connected to a light-emitting part, and a plurality of light-receiving optical fibers are also connected to a light-receiving part. Among these, one or more sets of light emitting optical fibers and light receiving optical fibers are connected to one detecting section, and a plurality of sets of such detecting sections are provided. That is, multiple sets of detection units are connected in parallel to one set of light projecting unit and light receiving unit. - If any one of the multiple sets of detectors detects the object to be detected, the detection signal is input to the light receiving unit, so the detection signals from the multiple sets of detectors can be processed by logical operation. The OR operation is performed and the signals are input to the light receiving section of the photoelectric switch body.

The number of detection units installed depends on the number of detection information required.
It can be implemented with two or three or more. As the number of detection units increases, the amount of light emitted to each detection unit decreases, so it is preferable to increase the output of the light emission unit of the photoelectric switch body or increase the number of light emission units. Furthermore, if the amount of light received by the light receiving section decreases, the sensitivity of the light receiving section may be increased or the number of light receiving sections may be increased.

The optical fiber type photoelectric switch according to claim 2 includes a photoelectric switch main body having a light emitting part, a light receiving part, and an amplifier unit, an optical fiber connected to the light emitting part and the light receiving part, and a detection part provided at the tip of the optical fiber. A reflection type optical fiber type photoelectric switch that emits and receives light with one detection section, the detection sections are provided in multiple stages, and a first
One end of a light emitting optical fiber connected to the light emitting part and another light receiving optical fiber connected to the light emitting part are connected to the detection part of the stage, and the detection parts of the second and subsequent stages are connected to the previous stage detection part. The other end of the light-receiving optical fiber of the first stage is connected as the light-emitting optical fiber of the detection part, and one end of another light-receiving optical fiber is connected to it, and the other end of the light-receiving optical fiber of the final stage detection part is connected to the light-emitting optical fiber of the detection part. It is connected to the light receiving section of the switch body.

The basic structure is the same as that of the above-mentioned invention according to claim 1, and also in this case, the structure of the detection section constitutes a reflective photoelectric switch.

In this invention, the light emitting optical fiber connected to the light emitting part of the photoelectric switch main body is first connected to the first stage detection part, and the light receiving optical fiber of the first stage detection part is connected to the light receiving part of the photoelectric switch main body. One end of the light-receiving optical fiber is connected to the light-emitting optical fiber of the second-stage detection section, and the other end of the light-receiving optical fiber of the final-stage detection section is connected to the light-receiving section of the photoelectric switch main body. It is now connected to.

The basic structure is the same as that of the above-mentioned invention according to claim 1, and also in this case, the structure of the detection section constitutes a reflective photoelectric switch.

In this invention, the light emitting optical fiber connected to the light emitting part of the photoelectric switch main body is first connected to the first stage detection part, and the light receiving optical fiber of the first stage detection part is connected to the light receiving part of the photoelectric switch main body. It is not connected to the optical fiber, but is used as a light emitting optical fiber for the second stage detection section. The light-receiving optical fiber of the final stage detection section is connected to the light-receiving section of the photoelectric switch body. In other words, multiple stages of detection sections are sequentially connected in series using optical fibers, and the light emitted from the light emitting section of the photoelectric switch body returns to the light receiving section through each detection section. It looks like this. Therefore, the detection signal will not be input to the light receiving section unless all the detection sections detect the object to be detected, and the detection signals from the multiple stages of detection sections will be ANDed and input to the light receiving section of the photoelectric switch main body. become.

The optical fiber type photoelectric switch according to claim 3 includes a photoelectric switch main body having a light emitting part, a light receiving part, and an amplifier unit, an optical fiber connected to the light emitting part and the light receiving part, and a detection part provided at the tip of the optical fiber. A transmission-type optical fiber type photoelectric switch in which a light-emitting detection section and a light-receiving detection section are disposed facing each other, the light-emitting section and the light-receiving section each having a plurality of sets of two optical fibers. Each one end of each set is connected, and each other end of each set is connected to one end.
A plurality of sets of detecting sections are provided such that they are separated into sets of light emitting detecting sections and light receiving detecting sections and are connected to each other.

The basic structure is the same as that of the invention according to claim 1 described above, but in the case of this invention, the detection section constitutes a transmission type photoelectric switch. In other words, the light emission detection section and the light reception detection section are installed separately and facing each other, and the light emitted from the light emission detection section is either directly received by the light reception detection section, or is emitted by the light reception detection section. The switch operation is performed depending on whether the light cannot be received by the light receiving detection section because it is blocked by an existing object to be detected.

In this invention, in the optical fiber, a plurality of light-emitting optical fibers are connected to the light-emitting part, and a plurality of light-receiving optical fibers are also connected to the light-receiving part.

Among them, one or more light emitting optical fibers are combined into one set and connected to one light emitting detection section, and the same one
A set of one or more light-receiving optical fibers is used.
The light emitting detecting section and the light receiving detecting section are connected to one light emitting detecting section and arranged to face each other to form one set of detecting sections. A plurality of sets of detection units as described above are installed. That is, multiple sets of detection units are connected in parallel to one set of light projecting unit and light receiving unit. If the object to be detected does not block the light in all detection sections, the light reception at the light receiving section cannot be blocked, so the detection signals from multiple sets of detection sections are ANDed and input to the light receiving section of the photoelectric switch body. It turns out.

The optical fiber type photoelectric switch according to claim 4 includes a photoelectric switch body having a light emitting part, a light receiving part, and an amplifier unit, an optical fiber connected to the light emitting part and the light receiving part, and a detection part provided at the tip of the optical fiber. A transmission-type optical fiber type photoelectric switch in which a detection section for light emission and a detection section for light reception are disposed facing each other, the detection sections are provided in a plurality of stages, and the detection section in the first stage is arranged to face the detection section for light emission. It is composed of a light emitting detection section connected to the light section by a light emitting optical fiber, and a light receiving detection section connected to one end of a light receiving optical fiber different from the light emitting optical fiber. The detection section includes a light emitting detection section to which the other end of the light reception optical fiber of the front detection section is connected, and a light reception detection section to which one end of a light reception optical fiber different from the light reception optical fiber of the front detection section is connected. The other end of another light-receiving optical fiber connected to the light-receiving detection section at the final stage is connected to the light-receiving section of the main body of the photoelectric switch 7.

The basic structure is the same as in the case of the invention according to claim 3 described above, and also in this case, the structure of the detection section constitutes a reflective photoelectric switch.

In this invention, the light projecting optical fiber connected to the light projecting section is first connected to the first stage detecting section, and the light receiving optical fiber is connected to the first stage detecting section. This light-receiving optical fiber is used as a light-emitting optical fiber in the next-stage detection section.In this way, multiple stages of detection sections are connected in order, and the light-receiving optical fiber of the final stage detection section is used as a photoelectric fiber. Connected to the light receiving section of the switch body.

In other words, multiple stages of detection sections are connected in series with optical fibers, and light emitted from the light emitting section of the photoelectric switch body passes through the multiple stages of detection sections in order and returns to the light receiving section. It's starting to come. Therefore, if an object to be detected is detected by any one detection section, the light is not received by the light receiving section, and the detection signals from the multiple stages of detection sections are ANDed and input to the light receiving section of the photoelectric switch body. [Function] According to the invention set forth in claim 1, in the plurality of sets of reflective detection sections installed in parallel as described above, each detection section is independently connected to the light emitting section and the light receiving section. Therefore, if one of the detection parts detects the object,
The detection signal is input to the light receiving section of the photoelectric switch body.

That is, the detection signals from the plurality of detection sections are ORed.

According to the invention as set forth in claim 2, as described above, in the plural stages of reflective detection sections installed in series, all the detection sections are connected in series from the light emitting section to the light receiving section. Therefore, a detection signal will not be input to the light receiving section of the photoelectric switch body unless all the detection sections detect the object to be detected. That is, the detection signals from a plurality of output sections are ANDed.

According to the invention set forth in claim 3, as described above, in the plurality of sets of transmission type detection sections installed in parallel, each detection section is independently connected to the light projecting section and the light receiving section. Therefore, if light passes through even one detection section, it will be received by the light receiving section of the photoelectric switch. Therefore, light reception at the light receiving section is interrupted only when all the detecting sections have detected the object to be detected. That is, the detection signals from the plurality of detection sections are AND-operated.

According to the invention set forth in claim 4, in the plural stages of transmission type detection sections installed in series as described above, all the detection sections are connected in series from the light emitting section to the light receiving section. Therefore, if any one of the detection sections detects the object to be detected, light reception at the light receiving section is blocked. That is, the detection signals from the plurality of detection sections are ORed.

〔Example〕

Next, embodiments of the present invention will be described in detail below with reference to the drawings.

In the embodiment shown in FIG. 1, an output can be obtained by OR-connecting reflective photoelectric switches.

The photoelectric switch main body 10 includes a light emitting element, a light receiving element, an amplifier unit, a power source, and other structures similar to those of a normal photoelectric switch. At one end of the photoelectric switch body 10,
A light projector 11 and a light receiver 12 are provided.

A light projecting optical fiber cable 20 is connected to the light projecting section 11 via a connector 21 . The optical fiber cable 20 for light projection is composed of an aggregate of a plurality of optical fibers 22. In the figure, an enlarged end view of the connector 21 is shown on the side of the connector 21, and in this figure,
Black circles represent individual optical fibers 22. Light receiving part 1
A light-receiving optical fiber cable 30 is connected to 2 via a connector 31. The light-receiving optical fiber cable 30 is also composed of an aggregate of a plurality of optical fibers 32. In the enlarged end view of the connector 31, the light-receiving optical fiber 32 is represented by a white circle.

The light-emitting optical fiber cable 20 and the light-receiving optical fiber cable 30 are brought together by a coupling tool 70 in the middle, and then divided into individual detection optical fiber cables 60 from a coupling tool 70 near the tip, and connected to the detection section 40 at the tip. is connected to. In the detection unit 40, a light emitting optical fiber 22 and a light receiving optical fiber 32 are arranged side by side. In the figure, an enlarged end view of the detection section 40 is shown on the side of the detection section 40, and the light emitting optical fiber 22 is shown as a black circle, and the light receiving optical fiber 32 is shown as a white circle. That is, the optical fiber cable 20.3 for light emission and light reception
From 0, split several optical fibers 22.32,
Take out to one optical fiber cable 60 for detection,
It is connected to the detection section 40.

The operation of the optical fiber type photoelectric switch having the above structure will be explained. Arrows in the figure indicate the progress of light.

The light emitted from the light emitting section 11 of the photoelectric switch main body 10 to the light emitting optical fiber 22 passes through different optical fibers 22 and is emitted from the tip of each detection section 40, 40. When there is an object, that is, a detection target M to be detected, in front of the detection unit 40, the light is reflected and reaches the detection unit 4 again.
The light returns to 0 and is received by the light receiving optical fiber 32. The received light that has entered the light receiving optical fiber 32 is input to the light receiving section 12 of the photoelectric switch main body 10, passes through the amplifier unit of the photoelectric switch main body 10, and an electrical detection signal is output and input to an external control device, etc. be done. As shown in FIG. 1, of the two detection units 40, 40, only the detection unit 40 located at the upper side in the figure detects the detection target M,
If the detecting section 40 located at the lower part of the figure does not detect the detection target M, the light receiving optical fiber 32 from the lower detecting section 40 cannot receive the light, but the upper detecting section 40
The light received is transmitted to the light receiving section 12 without any trouble through the light receiving optical fiber 32. That is, in this embodiment, if at least one of the plurality of detection sections 40 detects the detection target M, a detection signal is input to the light receiving section 12, using an OR connection.

FIG. 2 shows an embodiment partially modified from the above embodiment. In this embodiment, a large number of detection units 40 are used, and two optical fiber cables 20 for light projection are used. Each optical fiber cable 20 for light projection has a connector 21
and are connected to respective light projectors 11.11. Therefore, the photoelectric switch main body 10 is provided with a plurality of light projecting parts 11°11.

In this way, the number of detection units 40 installed can be increased arbitrarily as necessary. When the number of detection units 40 increases, if the light emitted from one light emission unit 11 is divided, each detection unit 4
Since the amount of light projected at 0 is reduced, the amount of light projected is increased by using a plurality of light projecting sections 11 as shown in the figure. Note that in order to increase the detection sensitivity of the light receiving section 12, the number of light receiving sections 12 may be increased to a plurality of pieces.

The embodiment shown in FIG. 3 obtains an AND-connected output using a reflective photoelectric switch. Structural parts common to those of the previous embodiment are given the same reference numerals, and redundant explanations will be omitted.

A light projection optical fiber cable 20 containing one optical fiber 22 is connected to the first stage detection section 40. One end of an optical fiber cable 61 containing an optical fiber 62 for receiving light is connected to the detection unit 40 . However, this optical fiber 62 and optical fiber cable 61 are not directly connected to the light receiving section 12, but are connected to the next stage detection section 41. This detection section 41 includes
The optical fiber 62 and the optical fiber cable 61
At the same time, an optical fiber cable 30 containing a light receiving optical fiber 32 is connected. That is, in this embodiment, two stages of detection sections 41 are provided.

The operation of the optical fiber type photoelectric switch having such a structure will be explained.

The light that is projected from the light projecting section 11 to the light projecting optical fiber 22 and from the light projecting optical fiber 22 at the tip of the detecting section 40 is reflected by the object M to be detected, and then passes through the optical fiber 62 of the detecting section 40 again. The light is received by That is, the optical fiber 62 functions as a light receiving optical fiber. The light transmitted through the optical fiber 62 is projected from the tip of the optical fiber 62 at the next stage detection section 41 . That is, in this detection section 41, the optical fiber 62 functions as a light projecting optical fiber. When the light is reflected by the detection target M, the light is received by the light receiving optical fiber 32 of the detecting section 41, and a detection signal is manually inputted to the light receiving section 12. In other words, the light projecting section 11, the detecting section 40, the detecting section 41, and the light receiving section 12 are connected in series through one optical path.

Therefore, when the detection target is detected by both the detection unit 40 and the detection unit 41, a detection signal is input to the light receiving unit 12, but if either the detection unit 40 or the detection unit 41 detects the detection target If the object M cannot be detected, that is, if the reflected light cannot be received, no detection signal is input to the light receiving section 12. The AND connection in FIG. This is an embodiment in which the detection units 40, 41 . ..., as shown in 42, a large number of detection units 40... are connected to an optical fiber 61.
The light emitting fiber optic cable 20 is connected to the detection section 40 at the first stage, and the detection section 42 at the final stage is connected to the detection section 40 at the first stage.
An optical fiber 30 for receiving light is connected to. In this way, an arbitrary number of detection units 40... can be connected by AND connection. As the number of detection units 40 increases, the amount of light emitted becomes insufficient. Therefore, the light emission units 11 are provided at two locations, and the optical fiber cables 20 connected to each location are sent together to the first stage detection unit 40. There is.

The embodiment shown in FIG. 5 obtains an AND-connected output using a transmission type photoelectric switch. Structural parts common to each of the embodiments described above are given the same reference numerals, and redundant explanations will be omitted.

In this embodiment, the light-emitting fiber optic cable 20 is connected to the coupler 70 by two light-emitting fiber optic cables 23.
It is divided into 23 parts. The divided light projection optical fiber cables 23 and 23 are connected to separate light projection detection sections 43 and 23 respectively.
．． It is connected to 43. Therefore, the light projecting optical fibers 22, 22 connected to the light projecting section 11 are separately connected to each light projecting detecting section 43, 43.

Light receiving detectors 44 and 44 are provided opposite to the light projecting detectors 43 and 43, respectively. For light reception, detection section 44
．． 44, an optical fiber cable 33.33 in which a light receiving optical fiber 32 is housed is connected, and the two optical fiber cables 33.33 are combined into one light receiving optical fiber cable 30 with a connector 70, and the light receiving part 12
is connected to. The light projected from the light projecting section 11 is
For each set of detection units, from the light emission optical fiber 22 to the light emission detection unit 43, the detection target space, and the light reception detection unit 44
, is transmitted to the light-receiving optical fiber 32, and is transmitted to the light-receiving section 12.
The light is received by

The operation of the optical fiber type photoelectric switch having such a structure will be explained.

When the detection target M blocks the optical path between the two sets of light emitting detectors 43 and light receiving detectors 44, the light receiving detector 44 at that location cannot receive light. However, if at least one of the light receiving detection sections 44 receives light, the light receiving section 1
Since the light is transmitted up to 2, no detection signal is output from the photoelectric switch main body IO. If the optical paths of both detection sections are blocked by the detection target M, it means that the light reception by the light receiving optical fiber 32 and the light receiving section 12 is blocked, and a detection signal is output. That is, the detection signals in the two sets of detection units 43 and 44 are OR-connected in the sense of logical operation, and the detection signals are output to the light receiving unit 1.
2 will be input.

As shown in FIG. 6, the number of detection units 43, 44 can be increased arbitrarily. Furthermore, if the number of installed detection units 43 and 44 increases and the amount of light becomes insufficient, the number of light projecting units 11 may be increased.

The embodiment shown in FIG. 7 obtains an output that is OR-connected using a transmission type photoelectric switch. Structural parts common to each of the embodiments described above are given the same reference numerals, and redundant explanations will be omitted.

In this embodiment, the light emitting optical fiber cable 20 containing the light emitting optical fiber 22 is connected to the light emitting detection section 43 of the first stage, and the light emitting optical fiber cable 20 is connected to the light emitting detecting section 43 facing the light emitting detecting section 43. A section 44 is provided. One end of an optical fiber cable 65 in which an optical fiber 64 is housed is connected to the light receiving detection section 44 . The other end of the optical fiber cable 65 is connected to the second stage light projection detection section 43. A second-stage light-receiving detector 44 is provided opposite to the light-emitting detector 43, and a light-receiving optical fiber cable 30 containing a light-receiving optical fiber 32 is connected to the light-receiving detector 44. There is. Therefore, in this embodiment, the optical fiber 64 functions as a light-receiving optical fiber in the first-stage detection section, and functions as a light-projecting optical fiber in the second-stage detection section.

The operation of the optical fiber type photoelectric switch having the above structure will be explained.

The path of light from the light projecting unit 11 is a light projecting optical fiber 22.
, first stage light emitting detection unit 43, detection target space, light receiving unit 43
Output section 44, optical fiber 64, second stage light projection detection section 43
, the detection target space is connected in series from the light-receiving detection section 44 to the light-receiving optical fiber 32, so if the detection target M blocks the optical path in either the first or second stage detection space, Since no light is transmitted to the light-receiving optical fiber 32, a detection signal is output.

That is, the output obtained by OR-connecting the detection signals of the first stage and the second stage is input to the light receiving section 12.

In this embodiment as well, the number of detection stages can be increased by increasing the light emitting detection section 43, the light reception detection section 44, and the intermediate optical fibers 64, and can be implemented with any number of stages. Furthermore, as shown in FIG. 8, the number of light projecting sections 11 can be increased to compensate for the decrease in the amount of light in the optical path and to improve the sensitivity of the light receiving section 12.

It is of course possible to use each of the optical fiber and detection section arrangement structures of the embodiments described above alone, but it is also possible to combine the structures of a plurality of embodiments. For example, if the detection signals of multiple AND-connected detection units and the detection signals of OR-connected multiple detection units are input to the same light receiving unit, more complex logic operation output can be achieved. It is also possible to obtain

〔Effect of the invention〕

In each of the optical fiber photoelectric switches according to claims 1 to 4 of the present invention described above, the optical fibers and the detection section connected to the light emitting section and the light receiving section of the photoelectric switch body are arranged in appropriate combinations. With such a simple structure, it is possible to input the results of logical operations on detection signals from a plurality of detection sections to the light receiving section. In other words, unlike conventional methods, it is not necessary to provide a photoelectric switch for each detection section, and one photoelectric switch body can be used for multiple detection sections, which reduces device costs and reduces the overall cost of the device. The installation space can also be reduced.

Conventional technology that electrically performs logical operations on the output of a photoelectric switch has a problem in that the internal circuits of the photoelectric switch electrically influence each other. Since it does not use , the above problems are completely solved. Moreover, since there is no electrical logic operation circuit and the output of the photoelectric switch can be used immediately, the response speed is extremely fast (and various controls can be performed quickly).

[Brief explanation of drawings]

Figure 1 is a structural layout diagram showing an embodiment of this invention, Figures 2-
FIG. 8 is a structural layout diagram showing different embodiments, FIG. 9 is a perspective view of a conventional example, and FIG. 10(a). (bl is a circuit configuration diagram. 10... Photoelectric switch main body 11... Light projecting section 12
...Light receiving part 22...Optical fiber for light emission 32.
...Optical fiber for light reception 40-44...Detection part M
...Detected object

Claims (1)

[Scope of Claims] 1. A photoelectric switch main body having a light emitter, a light receiver, and an amplifier unit, an optical fiber connected to the light emitter and the light receiver, and a detection unit provided at the tip of the optical fiber. This is a reflective optical fiber type photoelectric switch that emits and receives light in a detection part, and one end of each set of two or more optical fibers is connected to the light emitter and the light receiver, respectively. An optical fiber type photoelectric switch characterized in that a plurality of detection sections are provided such that each other end is connected to the same detection section. 2.Equipped with a photoelectric switch main body having a light emitter, a light receiver, and an amplifier unit, an optical fiber connected to the light emitter and the light receiver, and a detection unit provided at the tip of the optical fiber, one detection unit can transmit and receive light. A reflection type optical fiber type photoelectric switch is provided with a plurality of stages of the detection section, and the first stage detection section includes a light emitting optical fiber connected to the light emitting section and a separate light receiving section. The other end of the light-receiving optical fiber of the previous-stage detection section is connected to the detection section after the second stage as the light-emitting optical fiber of the detection section, and a separate An optical fiber type photoelectric switch characterized in that one end of a light receiving optical fiber is connected, and the other end of the light receiving optical fiber in a final stage detection section is connected to a light receiving section of a photoelectric switch main body. 3. A photoelectric switch main body having a light emitting part, a light receiving part, and an amplifier unit, an optical fiber connected to the light emitting part and the light receiving part, and a detection part provided at the tip of the optical fiber, which includes a light emitting detection part and a light receiving part. A transmission type optical fiber type photoelectric switch in which a detection part is disposed facing the light emitting part, and one end of each of a plurality of sets of two optical fibers is connected to the light emitting part and the light receiving part, respectively. An optical fiber type photoelectric switch characterized in that a plurality of sets of detection sections are provided such that each other end of each set is separated and connected to one set of light emission detection section and light reception detection section. . 4 A photoelectric switch body including a light emitting part, a light receiving part, and an amplifier unit, an optical fiber connected to the light emitting part and the light receiving part, and a detection part provided at the tip of the optical fiber. A transmission type optical fiber type photoelectric switch in which a detection section is disposed facing each other, the detection section is provided in multiple stages, and the detection section in the first stage is connected to the light projection section by a light projection optical fiber. It is composed of a light-emitting detection section connected to a light-receiving optical fiber different from the light-emitting optical fiber, and a light-receiving detection section connected to one end of a light-receiving optical fiber other than the light-emitting optical fiber. It consists of a light emitting detection section to which the other end of the optical fiber is connected, and a light receiving detection section to which one end of the light receiving optical fiber is connected, which is different from the light receiving optical fiber of the previous stage detection section. An optical fiber type photoelectric switch characterized in that the other end of another light receiving optical fiber connected to the section is connected to the light receiving section of the photoelectric switch main body.