JP2007228425A - Multiple optical axis photoelectric sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multiple optical axis photoelectric sensor capable of speedily detecting abnormality of mismatching between the number of projection means and the number of light-reception means. <P>SOLUTION: A projection element for detection as a terminal projection means which is driven for projection finally among projection elements for detection at a projector side, is driven for projection in a mode different from that of other projection elements for detection. If a waveform corresponding to the projection mode of the terminal projection element for detection can not be detected in a light reception signal Slr, a judgement circuit as a detection means then judges abnormality of mismatching that the number of light-reception elements for detection is less than the number of the projection elements for detection. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a multi-optical axis photoelectric sensor.

  2. Description of the Related Art Conventionally, a light projector having a plurality of light projecting means arranged in a straight line and a light receiver having a plurality of light receiving means arranged to face each of the light projecting means, each of the light projecting means and each light receiving facing each other. There is a multi-optical axis photoelectric sensor that detects whether or not each optical axis formed between means is in a light-shielded state (see, for example, Patent Document 1).

In such a multi-optical axis photoelectric sensor, each light projecting means is normally driven to project light sequentially at a predetermined light projecting timing, and each light receiving means receives light sequentially in synchronization with the light projecting timing of each light projecting means. Switchable as possible. The multi-optical axis photoelectric sensor described in Patent Document 1 is a so-called optical-synchronous multi-optical axis photoelectric sensor, and switching of the light-receiving means capable of receiving light is performed by receiving a synchronization optical signal transmitted from the projector side. This is performed based on the synchronization signal generated internally on the light receiver side. And it is configured to avoid erroneous detection between adjacent light receiving means by making it possible to detect and detect only light that forms a pair with the projecting light projecting means.
JP 2003-158448 A

  By the way, such a multi-optical axis photoelectric sensor is strongly required to have high installation flexibility and easy installation workability. For this reason, conventionally, the light receiving side is provided with a function as a light blocking detection means to increase the independence of the light projector and the light receiver, and a plurality of light projecting units and a light receiving unit are connected to form a pair. What can form a projector and a light receiver is used.

  However, such a multi-optical axis photoelectric sensor has a high degree of freedom in installation, so there is a possibility that the combination of projectors and light receivers or the number of connections will be wrong. May not match. In particular, when the number of light receiving means is insufficient, there is a problem that this insufficient area becomes a non-determinable area where the determination of the light shielding state cannot be performed.

  That is, as shown in FIG. 6, for example, in the multi-optical axis photoelectric sensor 32 in which the function of the light-shielding detection means is integrated on the light receiver 31 side, when the number of light-receiving means is “4”, the light projection on the light projector 33 side. Recognizing that the number of light means is “4”, the light receiver 31 determines that a series of light reception detection is completed at the stage of receiving the fourth optical axis (see FIG. 7). Note that a signal processing operation is performed after a series of light reception detection operations. The signal processing time required for this is generally set sufficiently longer than the light reception detection time. Even if a mismatch between the number of means and the number of light receiving means occurs, the synchronization does not shift. Therefore, when the number of connection between the light projecting unit 34 and the light receiving unit 35 is wrong, the number of light projecting means on the light projector 33 side is “8”, and the number of light receiving means on the light projector 33 side is “4”. The region corresponding to the second optical axis is the undecidable region.

  When the number of light receiving means is larger than the number of light projecting means, it is determined that there is no facing light projecting means, that is, a light receiving means that cannot receive light is generated, so that the region is determined to be in a light shielding state. become. For this reason, it is possible to estimate that the number of light projecting means and the number of light receiving means are inconsistent based on the light shielding determination result. However, it is more desirable that such anomaly is detected promptly and automatically.

  The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a multi-optical axis photoelectric sensor capable of quickly detecting an inconsistency between the number of light projecting means and the number of light receiving means. There is to do.

  In order to solve the above problems, the invention described in claim 1 includes a projector having a plurality of light projecting means arranged in a straight line, and a plurality of light receiving means arranged to face each of the light projecting means. Each of the light projecting units facing each other and a determination unit that determines whether or not each optical axis formed between the light receiving units is in a light-shielded state. The multi-optical axis photoelectric sensor is sequentially driven at a light projection timing, and the light receiver sequentially switches the light receiving means that can detect and receive light in synchronization with the light projection timing of each light projecting means, The gist of the invention is that the light receiver includes a detecting means for detecting a mismatch abnormality between the number of light projecting means and the number of light receiving means.

  According to the above configuration, it is possible to detect a mismatch abnormality in which the number of light projecting means and the number of light receiving means do not match. As a result, it is possible to prevent the occurrence of a non-determinable area where the light-shielding determination cannot be performed, thereby ensuring higher safety.

  According to a second aspect of the present invention, the terminal light projecting means is driven to project light in a different manner from the other light projecting means, and the light receiver is capable of receiving and detecting the different forms of light projection. And the detection means determines that the mismatch is abnormal when the light reception detection corresponding to the light projection mode of the terminal light projection means cannot be performed.

  According to a third aspect of the present invention, the light receiver sequentially switches the light receiving means capable of detecting light reception based on a synchronization signal input from the projector side, and the detection means includes the synchronization signal. Is input, and the synchronization signal includes a terminal identification waveform indicating the light projection operation of the terminal light projecting means, and the detection means is unable to detect the terminal identification waveform in the synchronization signal at a predetermined timing, The gist of determining that the discrepancy is inconsistent.

  According to each of the above configurations, identification information for detecting a discrepancy abnormality can be transmitted and received through a series of light projecting and receiving operations. Thereby, the same identification information can be reliably transmitted with a simple configuration, and a mismatch abnormality can be detected.

The gist of the invention described in claim 4 is that the terminal light projecting unit is driven to project at a light projecting timing different from the light projecting timing of each of the other light projecting units.
According to the above configuration, the light projecting drive of the terminal light projecting unit in a different configuration from the other light projecting units can be performed with a simple configuration. In addition, a characteristic end identification waveform can be included in the synchronization signal.

  According to a fifth aspect of the present invention, the light projector includes a transmission unit capable of transmitting an identification signal including the number of light projection units as the identification information, and the light receiver receives the identification signal. And the detecting means detects the inconsistency abnormality based on the received identification signal.

According to the above configuration, it is possible to more reliably detect a mismatch abnormality in which the number of light projecting means and the number of light receiving means do not match.
The gist of the invention described in claim 6 is that it comprises synchronization light projecting means and synchronization light receiving means for generating a synchronization signal.

  That is, in the optically synchronized multi-optical axis photoelectric sensor in which the synchronization line is not interposed between the projector and the receiver as in the above configuration, the degree of freedom of installation of the projector and the receiver is high. There is a high possibility that the above mismatch abnormality will occur due to the combination error. Therefore, a more remarkable effect can be acquired by applying to such a thing.

  According to a seventh aspect of the present invention, the synchronizing light projecting means is also used as the light projecting means provided in the projector, and the synchronizing light receiving means is the light receiving means provided in the light receiver. The gist is to be used together.

  According to the above configuration, the number of parts can be reduced by eliminating the dedicated light projecting means and light receiving means for synchronization, and the effective detection area can be expanded by making the area a light-shielding detection area. Can be achieved.

  According to an eighth aspect of the present invention, the light projector is formed by connecting a plurality of light projecting units having at least one light projecting unit, and the light receiver has a plurality of light receiving units having at least one light receiving unit. The gist is that they are connected.

  That is, in the unit-type multi-optical axis photoelectric sensor having the above-described configuration, since the degree of freedom of installation is high, there is a high possibility that the mismatch abnormality occurs due to an error in the number of connected units. Therefore, a more remarkable effect can be acquired by applying to such a thing. Furthermore, when applying the configuration of the above-mentioned claim 4, by making the terminal light projecting unit an independent light projecting unit, the light projecting timing of the terminal light projecting unit can be easily different from other light projecting units. This makes it possible to easily embody the present invention.

The gist of the invention described in claim 9 is that it comprises an informing means for informing the detection of the inconsistency abnormality.
According to the above configuration, it is possible to notify the operator of the detection of the mismatch abnormality and prompt the prompt correction.

  ADVANTAGE OF THE INVENTION According to this invention, the multi-optical axis photoelectric sensor which can detect rapidly the mismatch abnormality between the number of light projection means and the number of light reception means can be provided.

Hereinafter, an embodiment in which the present invention is embodied in an optical synchronous multi-optical axis photoelectric sensor will be described with reference to the drawings.
As shown in FIG. 1, the multi-optical axis photoelectric sensor 1 includes a projector 3 having a plurality of light projecting elements 2 and a light receiver 5 having a plurality of light receiving elements 4 arranged to face each of the light projecting elements 2. Has been.

  The multi-optical axis photoelectric sensor 1 of this embodiment is a light-synchronous multi-optical axis photoelectric sensor, and the projector 3 includes detection light projecting elements 6 a to 6 n and a synchronous light projecting element 7 as the light projecting element 2. And a light projecting circuit 8 for projecting and driving each of the light projecting elements 2. The light projecting circuit 8 sequentially drives the light projecting elements 6a to 6n for detection at a predetermined light projecting timing, and the optical signal is synchronized with the light projecting timing of each of the light projecting elements for detection 6a to 6n. The synchronizing light projecting element 7 is driven to transmit (synchronizing optical signal). The light projecting drive of the synchronization light projecting element 7 for transmitting the synchronization light signal is performed prior to the light projecting drive of each of the light projecting elements for detection 6a to 6n.

  On the other hand, the light receiver 5 includes, as the light receiving element 4, detection light receiving elements 9 a to 9 n and a synchronization light receiving element 10 corresponding to the respective detection light projecting elements 6 a to 6 n and the synchronization light projecting element 7 on the projector 3 side. In addition, a light receiving circuit 11 connected to each light receiving element 4 is provided. The synchronization light receiving element 10 is connected to the light receiving circuit 11 via the synchronization signal generating circuit 12, and a signal indicating that the synchronization optical signal output from the synchronization light receiving element 10 is detected (received) is the synchronization signal. In the signal generation circuit 12, the light reception timing, that is, the synchronization signal Ssy synchronized with the light projection timing of each of the detection light projecting elements 6 a to 6 n is converted and input to the light reception circuit 11. Then, the light receiving circuit 11 sequentially switches the detection light receiving elements 9a to 9n that can detect light reception (ON state) based on the synchronization signal Ssy, thereby pairing with the detection light projecting elements 6a to 6n that are projecting light. Only the detection light-receiving elements 9a to 9n forming the above can be received and detected, and the light-receiving signal Slr is generated by connecting the output signals of the detection light-receiving elements 9a to 9n at the timing.

  Further, in the present embodiment, whether or not the optical axis L formed between each of the opposing detection light projecting elements 6a to 6n and each of the detection light receiving elements 9a to 9n is in a light-shielded state in the light receiver 5. The light receiving signal Slr generated in the light receiving circuit 11 is input to the determining circuit 13. Then, the determination circuit 13 as the determination means sets the light axes L formed between the light projecting elements 2 and the light receiving elements 4 facing each other in a light-shielding state based on the signal level of the input light reception signal Slr. It is determined whether or not there is.

  That is, as shown in FIG. 2, in a state where each detection light receiving element 9a to 9n detects the light emission of each corresponding light projecting element 2, the light reception signal Slr output from the light receiving circuit 11 is detected. It has a pulse-like waveform whose signal level becomes Hi at timing synchronized with the light projection timing of the optical elements 6a to 6n. On the other hand, if any of the detection light receiving elements 9a to 9n cannot detect the light emission of the corresponding detection light projecting elements 6a to 6n, the timing corresponding to the detection light receiving element (detection section). ), The signal level remains Lo. Then, when there is a section where the signal level remains Lo in the input Slr, the determination circuit 13 determines that the optical axis L corresponding to the section is in a light shielding state (for example, the same X-th optical axis in the figure).

  The determination circuit 13 outputs a light reception detection signal Sse indicating the result of the light shielding determination. In this embodiment, the determination circuit 13 is configured to turn on the output of the light reception detection signal Sse when the optical axis L in the light shielding state cannot be detected.

(Disagreement abnormality detection function)
Next, the mismatch detection function between the number of light projecting means and the number of light receiving means in the multi-optical axis photoelectric sensor of this embodiment will be described.

  In the multi-optical axis photoelectric sensor 1 of the present embodiment, the light receiver 5 includes the number of the detection light projecting elements 6a to 6n and the detection light receiving elements 9a to 9n based on the identification information transmitted from the light projector 3 side. Detect a discrepancy error that does not match the number.

  Specifically, as shown in FIGS. 2 and 3, in the present embodiment, among the detection light projecting elements 6a to 6n on the light projector 3 side, the terminal light projecting element 6n at the end that is driven to perform light projection lastly. Are projected and driven in a manner different from the other detection light projecting elements (6a to 6n-1). Then, the determination circuit 13 serving as the detection means cannot detect the waveform corresponding to the light projection form of the terminal detection light projecting element 6n in the light reception signal Slr, and detects the light projecting elements 6a to 6a. The number of the light receiving elements 9a to 9n for detection is smaller than the number of 6n, and it is determined that the above-mentioned mismatch abnormality is present.

  That is, in this embodiment, the identification information for detecting the inconsistency abnormality is transmitted from the light projector 3 side to the light receiver 5 side through the light projection drive of the terminal detection light projecting element 6n as the terminal light projecting means, The light receiver 5 receives the identification information through a series of light detection. Then, the determination circuit 13 serving as a detecting means has the identification information embedded in the received light signal Slr, that is, the presence / absence of the terminal identification waveform corresponding to the light projection of the terminal detection light projecting element 6n driven in a different manner. By detecting this, the above-mentioned mismatch abnormality is detected.

  More specifically, in the present embodiment, each of the detection light projecting elements (6a to 6n-1) other than the terminal detection light projecting element 6n is periodically projected at a constant light projecting interval “t0”. On the other hand, the light projection interval between the detection light projecting element (6n-1) immediately before the end and the detection light projecting element 6n at the end is set to "t1". That is, the terminal detection light projecting element 6n is driven to project at a different light projection timing from the other detection light projecting elements (6a to 6n-1). Then, the determination circuit 13 determines that there is a discrepancy abnormality when a waveform indicating that light reception is detected at the light projection interval “t1” cannot be detected in the light reception signal Slr.

  For example, even if the number of light projecting elements on the light projector 3 side is “N” due to a mismatch error, the number of light receiving elements on the light receiver 5 side is only “M” (M <N). The device 5 side (determination circuit 13) recognizes that the number of light projecting elements on the light projector 3 side is also “M”. Here, in the present embodiment, the determination circuit 13 includes the Mth light receiving element that the determination circuit 13 recognizes as the “terminal optical axis” in the light reception signal Slr and the M−1th previous one. It is determined whether or not there is a waveform indicating that the light reception detection interval between the light receiving elements, that is, the light projection interval is “t1”. When the waveform cannot be detected (in this example, the light projection interval is constant at “t0”), the number of the detection light receiving elements 9a to 9n is larger than the number of the detection light projection elements 6a to 6n. It is determined that the above-mentioned inconsistency abnormality is small. In the present embodiment, the determination circuit 13 is configured to leave the output of the light reception detection signal Sse OFF when a mismatch abnormality is detected.

  As described above, according to the above configuration, it is possible to reliably detect a mismatch abnormality in which the number of the detection light projecting elements 6a to 6n and the number of the respective detection light receiving elements 9a to 9n do not match with a simple configuration. As a result, it is possible to prevent the occurrence of a non-determinable area where the light-shielding determination cannot be performed, thereby ensuring higher safety.

In addition, you may change this embodiment as follows.
In the present embodiment, identification information for detecting a discrepancy abnormality is transmitted from the light projector 3 side to the light receiver 5 side through the light projection drive of the terminal detection light projecting element 6n, and the light receiver 5 receives a series of light receiving operations. The identification information is received through detection. Then, the determination circuit 13 detects the inconsistency abnormality by determining whether or not there is a waveform (terminal identification waveform) corresponding to the light projection form of the terminal detection light projecting element 6n in the light reception signal Slr. It was decided. However, the present invention is not limited to this. The terminal identification waveform indicating the projection operation of the terminal detection light projecting element 6n is included in the synchronization signal Ssy, and the above-mentioned mismatch abnormality is determined depending on whether the terminal identification waveform can be detected at a predetermined timing. It is good also as detecting.

  That is, as in the above embodiment, the terminal detection light projecting element 6n is driven to project at a light projecting timing (light projecting interval "t1") different from the other detection light projecting elements (6a to 6n-1). In this case, the synchronization signal Ssy also has a terminal identification waveform having a pulse interval of “t1” corresponding thereto (see FIGS. 2 and 3). Accordingly, in the synchronization signal Ssy, the terminal identification waveform is detected at a predetermined timing, and in the example shown in FIG. 3, the light receiving detection of the M-1th optical axis and the Mth optical axis, which the determination circuit 13 recognizes as the “terminal optical axis”. If it cannot be detected at the timing to be performed, it can be determined that the above-mentioned mismatch is abnormal.

  The terminal identification waveform in this case changes the pulse interval as shown in the above example, and also corresponds to the pulse corresponding to the terminal detecting light projecting element 6n (Nth optical axis) as shown in FIG. It can be expressed by other methods such as making the width longer than others, or making the pulse shape corresponding to the terminal detection light projecting element 6n (Nth optical axis) into a burst shape as shown in FIG. May be. Further, as shown in FIG. 4 (c), the synchronization signal Ssy further includes each detection projection after a pulse waveform corresponding to the Nth optical axis corresponding to the terminal detection projection element 6n. It is good also as a structure containing the waveform to the effect that the sequential light projection of optical element 6a-6n was complete | finished.

  Similarly to the present embodiment, in the case of performing the mismatch abnormality determination based on whether or not the light receiving signal Slr has a waveform corresponding to the light projecting form of the terminal detecting light projecting element 6n, the light receiving signal Slr 4A and 4B may be included, that is, the terminal detection light projecting element 6n may be driven to project in a characteristic manner. In this case, it goes without saying that the light receiving circuit 11 as the light receiving detecting means is configured to be able to detect the light projection of the different mode.

  Furthermore, when there is no waveform corresponding to the light projecting form of the terminal detecting light projecting element 6n in the light receiving signal Slr over a plurality of scanning periods in which the signal processing operation following the light receiving detection operation is one cycle ( In the another example, the synchronization signal Ssy may be configured to determine that the inconsistency abnormality is present when the terminal identification waveform indicating the light projection operation of the terminal detection light projecting element 6n is not included. With such a configuration, it is possible to avoid misjudgment and detect a mismatch abnormality more accurately.

  A transmitting unit capable of transmitting an identification signal including the number of light projecting elements as identification information is provided on the light projector side, and a receiving unit capable of receiving this is provided on the light receiving side. And a detection means is good also as a structure which detects the said discrepancy abnormality based on the received identification signal. With such a configuration, a mismatch abnormality can be detected more reliably. In this configuration, when an activation signal (start pulse) is transmitted from the projector side at the time of activation, a pulse signal indicating the number of light projecting elements is output as an identification signal for a predetermined period. And it can implement easily by detecting the pulse signal in the light receiver side. In this case, dedicated transmission means and reception means may be provided on the light projector side and the light receiver side, and identification information indicating the number of light projecting elements may be included in the synchronization signal Ssy.

  In this embodiment, the light projector 3 and the light receiver 5 are separated from the light receiving elements 9a to 9n for detection and the light projecting elements 6a to 6n for detection, respectively, The synchronization light receiving element 10 is provided as a light receiving means. However, the present invention is not limited to this, and the synchronization light projecting element 7 may be used also as the detection light receiving elements 9a to 9n, and the synchronization light receiving element 10 may be used as the detection light projecting elements 6a to 6n. .

In the present embodiment, the present invention is embodied in the optically synchronized multi-optical axis photoelectric sensor 1, but may be embodied in a configuration in which a projector and a light receiver are connected by a synchronization line.
Further, like the multi-optical axis photoelectric sensor 21 shown in FIG. 5, the light projector 23 and the light receiver 25 each have a light projecting unit 27 having at least one light projecting element 26 and a light receiving unit having at least one light receiving element 28. You may embody in what is formed by connecting 29.

  That is, in such a unit-type multi-optical axis photoelectric sensor 21, an error in mismatch between the number of light projecting elements and the number of light receiving elements tends to occur due to an error in installation. Therefore, a more remarkable effect can be obtained by applying the present invention to such a configuration. Furthermore, by making the terminal light projecting element 26n an independent light projecting unit 27n, it is possible to easily make the light projecting timing of the terminal light projecting element 26n different from the other light projecting elements 26, Thereby, the present invention can be easily realized.

In the present embodiment, the determination circuit 13 has functions as a determination unit and a detection unit. However, the configuration is not limited to this, and an independent detection unit may be provided.
Further, a notification means for notifying the occurrence of a mismatch abnormality may be provided, and the specific configuration thereof may be anything such as lighting of a warning lamp or output of a warning sound.

Next, technical ideas other than the claims that can be understood from the above embodiments will be described.
(Appendix 1) In the multi-optical axis photoelectric sensor according to claim 2, each of the light projecting means is repeatedly driven by the sequential light with a predetermined scan period, and the detecting means includes a plurality of continuous light sensors. A multi-optical axis photoelectric sensor, wherein when the received light detection corresponding to the light projection mode of the terminal light projecting unit cannot be performed over the scan period, it is determined that the mismatch is abnormal.

  (Supplementary note 2) In the multi-optical axis photoelectric sensor according to claim 3, each of the light projecting means is driven to emit light sequentially and repeatedly at a predetermined scan period, and the detecting means includes a plurality of continuous light sensors. A multi-optical axis photoelectric sensor characterized in that, when the terminal identification waveform cannot be detected over the scan period, it is determined that the mismatch is abnormal. According to each of the above configurations, misjudgment abnormality can be detected with higher accuracy while avoiding erroneous determination.

The schematic block diagram of the multi-optical axis photoelectric sensor of this embodiment. The wave form diagram explaining the aspect of the light-shielding detection of this embodiment. The wave form diagram explaining the aspect of the mismatch abnormality detection of this embodiment. (A) (b) (c) The wave form diagram explaining the aspect of the mismatch abnormality detection of another example. The schematic block diagram of the multi-optical axis photoelectric sensor of this embodiment. Explanatory drawing of a mismatch abnormality and its cause. The waveform diagram explaining the cause of the occurrence of the discrepancy abnormality.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,21 ... Multi-optical axis photoelectric sensor, 2, 26, 26n ... Light projecting element, 3, 23 ... Light projector, 4, 28 ... Light receiving element, 5, 25 ... Light receiver, 6a-6n ... Light projecting element for detection, 7: Light projecting element for synchronization, 8: Light projecting circuit, 9a to 9n: Light receiving element for detection, 10: Light receiving element for synchronization, 11: Light receiving circuit, 12: Sync signal generating circuit, 27, 27n: Light projecting unit, 29. Light receiving unit.

Claims (9)

A light projector having a plurality of light projecting means arranged in a straight line, a light receiver having a plurality of light receiving means arranged to face each of the light projecting means, and between each of the light projecting means and each light receiving means facing each other. Determining means for determining whether or not each optical axis to be formed is in a light-shielded state, each light projecting means is sequentially projected at a predetermined light project timing, and the light receiver A multi-optical axis photoelectric sensor for sequentially switching the light receiving means capable of receiving and detecting light in synchronization with the light projection timing of each light projecting means,
The multi-optical axis photoelectric sensor, wherein the light receiver includes a detecting unit that detects a mismatch abnormality between the number of light projecting units and the number of light receiving units based on identification information transmitted from the projector side. The multi-optical axis photoelectric sensor according to claim 1,
The terminal light projecting unit is driven to project light in a mode different from each of the other light projecting units, and the light receiver includes a light receiving detection unit capable of receiving and detecting the light projection of the different mode
The multi-optical axis photoelectric sensor, wherein the detection unit determines that the mismatch is abnormal when the received light detection corresponding to the light projection mode of the terminal light projection unit cannot be performed. The multi-optical axis photoelectric sensor according to claim 1,
The light receiver sequentially switches the light receiving means capable of detecting and receiving light based on a synchronization signal input from the projector side,
The detection means is supplied with the synchronization signal, and the synchronization signal includes a terminal identification waveform indicating the light projection operation of the terminal light projection means,
The multi-optical axis photoelectric sensor, wherein the detection unit determines that the mismatch is abnormal when the terminal identification waveform cannot be detected in the synchronization signal at a predetermined timing. The multi-optical axis photoelectric sensor according to claim 2 or 3,
The terminal light projecting means is driven to project light at a light projection timing different from the light projection timing of each of the other light projecting means. The multi-optical axis photoelectric sensor according to claim 1,
The light projector includes a transmission unit capable of transmitting an identification signal including the number of light projection units as the identification information, and the light receiver includes a reception unit that receives the identification signal.
The detecting means detects the inconsistency abnormality based on the received identification signal;
A multi-optical axis photoelectric sensor. In the multi-optical axis photoelectric sensor according to any one of claims 1 to 5,
A synchronization light projecting unit and a synchronization light receiving unit for generating a synchronization signal;
A multi-optical axis photoelectric sensor. The multi-optical axis photoelectric sensor according to claim 6,
The synchronizing light projecting means is also used as the light projecting means provided in the projector, and the synchronizing light receiving means is also used as the light receiving means provided in the light receiver;
A multi-optical axis photoelectric sensor. In the multi-optical axis photoelectric sensor according to any one of claims 1 to 7,
The light projector is formed by connecting a plurality of light projecting units having at least one light projecting unit, and the light receiver is formed by connecting a plurality of light receiving units having at least one light receiving unit. Multi-optical axis photoelectric sensor. In the multi-optical axis photoelectric sensor according to any one of claims 1 to 8,
Providing an informing means for informing detection of the inconsistency abnormality;
A multi-optical axis photoelectric sensor.

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