Sensor Systems

Abstract

To detect the wiring abnormality and internal abnormality of a sensor without having to add a load, as compared with a conventional structure.SOLUTION: An abnormality detection device 3 comprises: a first output circuit 301 for outputting a first detection signal that indicates whether a detection body is located in a first range in a normal operating range; a second output circuit 302 for outputting a second detection signal that indicates whether the detection body is located in a second range, different from the first range, in the normal operating range; a power supply 304; a first switching element 305 for switching electrical continuity in accordance with the first detection signal; a second switching element 306 for switching electrical continuity in accordance with the second detection signal; a first load 307; a second load 308; and a detection unit 309 for detecting, on the basis of the states of the first and the second loads, the abnormality of a power supply wiring 311, a first output wiring 313, a second output wiring 314 and a ground wiring 312 and / or the internal abnormality of the sensor 1.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This invention relates to an abnormality detection device and a sensor system including the abnormality detection device.

Background Art

[0002] Conventionally, when a wiring abnormality such as a disconnection or a short circuit occurs in a conducting wire used inside a photoelectric sensor, the wiring abnormality can be detected based on the states of a first load and a second load connected to the conducting wire. A photoelectric sensor configured to do so is known (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the sensor of Patent Document 1 above, although a wiring abnormality of the sensor can be detected, an abnormality occurring inside the sensor (hereinafter referred to as an internal abnormality) cannot be detected. Therefore, the user may require a lot of time until noticing the internal abnormality. Further, when a large number of sensors are used inside a certain device, even if an internal abnormality occurs in any one of the sensors, it may take a lot of time to identify the abnormal location. Thus, it is conceivable to incorporate means for detecting the internal abnormality (for example, a known internal abnormality detection circuit) into the conventional sensor configuration described in Patent Document 1, so as to detect not only the wiring abnormality of the sensor but also the internal abnormality.

[0005] However, since the conventional sensor described in Patent Document 1 above is configured for the purpose of detecting wiring abnormalities in the sensor, it is conceivable that in order to detect internal abnormalities in addition to wiring abnormalities, it may be necessary to add an additional load for detecting internal abnormalities in addition to the first and second loads.

[0006] This invention was made to solve the above-mentioned problems, and aims to provide an abnormality detection device that can detect both wiring abnormalities and internal abnormalities of sensors without adding any load to the conventional configuration. [Means for solving the problem]

[0007] An abnormality detection device according to this invention includes: a first output circuit that outputs a first detection signal indicating whether or not the detected object is located in a first range within the normal operating range based on the detection result from a sensor; a second output circuit that outputs a second detection signal indicating whether or not the detected object is located in a second range different from the first range within the normal operating range based on the detection result from a sensor; a power supply with a positive terminal connected to a power supply wire and a negative terminal connected to a ground wire; and a first circuit that has one end connected to a power supply wire and the other end connected to one end of the first output wire, and switches the conduction state in accordance with the first detection signal output by the first output circuit. The system comprises a switching element, a second switching element with one end connected to a power supply wire and the other end connected to one end of a second output wire, which switches its conduction state in accordance with a second detection signal output by a second output circuit, a first load with one end connected to the other end of a first output wire and the other end connected to a ground wire, a second load with one end connected to the other end of a second output wire and the other end connected to a ground wire, and a detection unit that detects at least one of abnormalities in the power supply wire, the first output wire, the second output wire, and the ground wire, as well as an internal abnormality of the sensor, based on the state of the first load and the state of the second load.

[0008] Furthermore, the abnormality detection device according to this invention includes: a first output circuit that outputs a first detection signal indicating whether or not the detected object is located in a first range within the normal operating range based on the detection result from the sensor; a second output circuit that outputs a second detection signal indicating whether or not the detected object is located in a second range different from the first range within the normal operating range based on the detection result from the sensor; a power supply with a positive terminal connected to the power supply wiring and a negative terminal connected to the ground wiring; and a device with one end connected to the ground wiring and the other end connected to one end of the first output wiring, which switches the conduction state in accordance with the first detection signal output by the first output circuit. The system comprises a first switching element, a second switching element with one end connected to a ground wire and the other end connected to one end of a second output wire, which switches its conduction state in accordance with a second detection signal output by a second output circuit, a first load with one end connected to the other end of the first output wire and the other end connected to a power supply wire, a second load with one end connected to the other end of the second output wire and the other end connected to a power supply wire, and a detection unit that detects at least one of abnormalities in the power supply wire, the first output wire, the second output wire, and the ground wire, as well as an internal abnormality of the sensor, based on the state of the first load and the state of the second load. [Effects of the Invention]

[0009] According to this invention, with the configuration described above, it becomes possible to detect both wiring abnormalities and internal abnormalities of the sensor without adding any load compared to the conventional configuration. [Brief explanation of the drawing]

[0010] [Figure 1] This figure shows an example configuration of an anomaly detection device and a sensor system equipped with an anomaly detection device according to Embodiment 1. [Figure 2] This diagram illustrates the relationship between detection distance and detection level in Embodiment 1. [Figure 3] This figure illustrates examples of the first detection signal and the second detection signal in Embodiment 1. [Figure 4]This diagram illustrates wiring abnormalities and internal abnormalities in Embodiment 1, as well as the signal values ​​in each state. [Modes for carrying out the invention]

[0011] The embodiments of this invention will be described in detail below with reference to the drawings. Embodiment 1. Figure 1 shows an example configuration of an anomaly detection device 3 according to Embodiment 1 and a sensor system equipped with this anomaly detection device 3.

[0012] The sensor system according to Embodiment 1, as shown in Figure 1, is configured to include a sensor 1 and an anomaly detection device 3. Sensor 1 detects the presence or absence of a target object and outputs a signal (detection signal) indicating the detection result. Sensor 1 is composed of, for example, a proximity sensor and includes a target object detection unit 2 as its main component.

[0013] If the sensor 1 is a high-frequency oscillation type proximity sensor, the detection unit 2 has an oscillation circuit including, for example, a detection coil, a capacitor, and a nonlinear amplifier. The method by which the detection unit 2 detects the presence or absence of a detection object is known, so a detailed explanation will be omitted, but for example, the detection unit 2 determines the presence or absence of a detection object based on the level of the detection signal obtained when detecting the detection object (detection level). For example, in the case of a proximity sensor, the detection level usually changes according to the distance from the sensor's detection reference point to the detection object (detection distance).

[0014] Figure 2 illustrates the relationship between detection distance and detection level. The horizontal axis of Figure 2 represents detection distance (mm), and the vertical axis represents detection level. Reference numeral 201 indicates the detection distance and the change in detection level at each detection distance for a particular object.

[0015] As shown in Figure 2, three thresholds (approximately 400, 2,550, and 3,400) are pre-set for the detection level. For example, the detection unit 2 determines that an object is present when the detection level is between approximately 400 and 2,550. On the other hand, the detection unit 2 determines that there is no object present when the detection level is between approximately 2,550 and 3,400. For example, in the case of the object shown by reference numeral 201, the detection unit 2 determines that there is no object present when the detection distance is approximately 1.4 mm or more because the detection level is approximately 2,550 or more. However, when the detection distance is less than approximately 1.4 mm, the detection level falls below approximately 2,550, and the detection unit determines that an object is present.

[0016] Here, the range of detection levels in which the detection unit 2 determines that a detection object is present, i.e., the range of detection levels from approximately 400 to approximately 2,550, is referred to as the "first range," and the range of detection levels in which the detection unit 2 determines that no detection object is present, i.e., the range of detection levels from approximately 2,550 to approximately 3,400, is referred to as the "second range." The combined range of the first and second ranges is referred to as the "normal operating range." In other words, the detection unit 2 determines that a detection object is present when the detection object is located within the first range of the normal operating range and outputs a signal indicating the presence of a detection object. The detection unit 2 also determines that no detection object is present when the detection object is located within the second range of the normal operating range and outputs a signal indicating the absence of a detection object.

[0017] Furthermore, the detection unit 2 determines that an abnormality (internal abnormality) such as an oscillation abnormality has occurred inside the sensor 1 if the detection level is less than approximately 400 or if the detection level is greater than approximately 3,400. Here, the range of detection levels in which the detection unit 2 determines that an internal abnormality has occurred in the sensor 1, i.e., the range in which the detection level is less than approximately 400 or greater than approximately 3,400, is called the "abnormal operating range." The detection unit 2 determines that there is an internal abnormality when the detection level is within the abnormal operating range and outputs a signal indicating the presence of an internal abnormality. The detection unit 2 may also be equipped with a known internal abnormality detection circuit and use the function of this internal abnormality detection circuit to determine whether or not there is an internal abnormality in the sensor 1.

[0018] The abnormality detection device 3 includes a first output circuit 301, a second output circuit 302, a power supply 304, a first switching element 305, a second switching element 306, a first load 307, a second load 308, and a detection unit 309. Here, as an example, among these components, the first output circuit 301, the second output circuit 302, the first switching element 305, and the second switching element 306 are provided inside the housing of the sensor 1, and an example where the power supply 304, the first load 307, and the second load 308 are provided outside the housing of the sensor 1 will be described. However, this arrangement is merely an example, and the arrangement of each component is not limited to this.

[0019] The first output circuit 301 outputs a first detection signal indicating whether the detected object is located within a first range in the normal operation range based on the detection result by the detected object detection unit 2 (sensor 1).

[0020] The second output circuit 302 outputs a second detection signal indicating whether the detected object is located within a second range different from the first range in the normal operation range based on the detection result by the detected object detection unit 2 (sensor 1).

[0021] Here, examples of the first detection signal and the second detection signal will be described while referring to FIG. 3. As shown in FIG. 3, for example, when the first output circuit 301 detects that the detected object is located within the first range in the normal operation range (the presence of the detected object) by the detected object detection unit 2 (sensor 1), it outputs 1 (High) as the first detection signal indicating that the detected object is located within the first range. Further, when the first output circuit 301 detects that the detected object is not located within the first range in the normal operation range by the detected object detection unit 2 (sensor 1), it outputs 0 (Low) as the first detection signal indicating that the detected object is not located within the first range. The output terminal of the first output circuit 301 is connected to the base terminal of the first switching element 305.

[0022] Furthermore, the second output circuit 302 outputs a second detection signal of 1 (High) to indicate that the object is located in the second range within the normal operating range, for example, when the object detection unit 2 (sensor 1) detects that the object is located in the second range within the normal operating range (i.e., the object is not present). Also, the second output circuit 302 outputs a second detection signal of 0 (Low) to indicate that the object is not located in the second range, when the object detection unit 2 (sensor 1) detects that the object is not located in the second range within the normal operating range. The output terminal of the second output circuit 302 is connected to the base terminal of the second switching element 306.

[0023] Power supply 304 has its positive terminal connected to power supply wiring 311 and its negative terminal connected to ground wiring 312.

[0024] The first switching element 305 is composed of, for example, a first PNP transistor. One end of the first switching element 305 is connected to the power supply wiring 311, and the other end is connected to one end of the first output wiring 313. Specifically, the emitter terminal of the first switching element 305 is connected to the power supply wiring 311, and the collector terminal is connected to one end of the first output wiring 313. The base terminal of the first switching element 305 is connected to the output terminal of the first output circuit 301. The first switching element 305 switches its conduction state in response to a first detection signal input to the base terminal from the first output circuit 301.

[0025] The second switching element 306 is composed of, for example, a second PNP transistor. One end of the second switching element 306 is connected to the power supply wiring 311, and the other end is connected to one end of the second output wiring 314. Specifically, the emitter terminal of the second switching element 306 is connected to the power supply wiring 311, and the collector terminal is connected to one end of the second output wiring 314. The base terminal of the second switching element 306 is connected to the output terminal of the second output circuit 302. The second switching element 306 switches its conduction state in response to a second detection signal input to the base terminal from the second output circuit 302.

[0026] The first load 307 has one end connected to the other end of the first output wiring 313 and the other end connected to the ground wiring 312. The second load 308 has one end connected to the other end of the second output wiring 314 and the other end connected to the ground wiring 312. The ground wiring 312 is also connected to the internal circuitry (not shown) of the sensor 1.

[0027] The detection unit 309 is connected to the first load 307 and the second load 308, and is capable of acquiring the status of both loads. Based on the status of the first load 307 and the second load 308, the detection unit 309 detects at least one of the following: an abnormality in the power supply wiring 311, the first output wiring 313, the second output wiring 314, and the ground wiring 312, and an internal abnormality in the sensor 1. Here, an abnormality in the power supply wiring 311, the first output wiring 313, the second output wiring 314, and the ground wiring 312 refers to a break in each of these wirings, and a short circuit in any two of these wirings.

[0028] Specifically, the detection unit 309 determines that there is no abnormality when the state of the first load 307 and the state of the second load 308 are inversely related. On the other hand, when the state of the first load 307 and the state of the second load 308 are the same, the detection unit 309 detects at least one of the following: an abnormality in the power supply wiring 311, the first output wiring 313, the second output wiring 314, and the ground wiring 312, as well as an internal abnormality in the sensor 1.

[0029] Furthermore, the detection unit 309 detects abnormalities in the power supply wiring 311, the first output wiring 313, the second output wiring 314, and the ground wiring 312 when the state of the first load 307 and the state of the second load 308 change from being inverted to being identical, depending on whether the detected object is located within the first or second range.

[0030] The function of the detection unit 309 is realized, for example, by a CPU (Central Processing Unit) of a monitoring device (not shown) executing a predetermined program loaded into a memory (not shown).

[0031] Next, an example of the operation of the abnormality detection device 3 according to Embodiment 1 will be described with reference to Figure 4. Figure 4 is a diagram illustrating internal abnormalities and wiring abnormalities in Embodiment 1, and the signal values ​​in each of these states.

[0032] For the sake of clarity, the first output circuit 301, as explained in Figure 3, outputs 1 (High) as a first detection signal indicating that the detected object is located within the first range in the normal operating range when the detected object detection unit 2 (sensor 1) detects that the detected object is located within the first range in the normal operating range (i.e., the presence of the detected object), and outputs 0 (Low) as a first detection signal indicating that the detected object is not located within the first range when it is detected that the detected object is not located within the first range in the normal operating range.

[0033] Furthermore, the second output circuit 302 outputs 1 (High) as a second detection signal indicating that the detected object is located in the second range within the normal operating range when the detected object detection unit 2 (sensor 1) detects that the detected object is located in the second range within the normal operating range. Also, the second output circuit 302 outputs 0 (Low) as a second detection signal indicating that the detected object is not located in the second range when, for example, the detected object detection unit 2 detects that the detected object is not located in the second range within the normal operating range.

[0034] Furthermore, when a signal of 1 (High) is output, it means that current flows in the direction of the signal's output, and when a signal of 0 (Low) is output, it means that no current flows in the direction of the signal's output. In addition, the initial state of both the first load 307 and the second load 308 is assumed to be a state where 0 (Low) is applied.

[0035] (1. If Sensor 1 is functioning correctly) (1-a. If a detection sample is present) If a detection object is present (i.e., the detection object is located within the first range), the detection object detection unit 2 outputs a signal indicating the presence of a detection object.

[0036] When the first output circuit 301 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 1 as the first detection signal from its output terminal. This first detection signal is input to the base terminal of the first PNP transistor 305.

[0037] When the second output circuit 302 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 0 as a second detection signal from its output terminal. This second detection signal is input to the base terminal of the second PNP transistor 306.

[0038] Since the first detection signal (1) output from the first output circuit 301 is input to the base terminal of the first PNP transistor 305, no current flows from the base terminal to the first output circuit 301, and no current flows between the emitter terminal and the collector terminal. In other words, the first PNP transistor 305 is in a non-conducting state. Therefore, the first load 307 is maintained in a state where 0 is applied.

[0039] The second PNP transistor 306 receives the second detection signal (0) output from the second output circuit 302 as input to its base terminal. As a result, current flows from the base terminal towards the second output circuit 302, and also between the emitter and collector terminals. In other words, the second PNP transistor 306 becomes conductive. Therefore, the second output wire 314 outputs a second output signal of 1, and the second output signal (1) is applied to the second load 308.

[0040] The detection unit 309 acquires the state of the first load 307 (0 indicates application) and the state of the second load 308 (1 indicates application), and determines that there is no abnormality because the states of both loads are inverted relative to each other.

[0041] Furthermore, the detection unit 309 may display the results of the anomaly detection on a monitor (not shown) provided by the monitoring device and present them to the user. This also applies to the following explanation.

[0042] (1-b. If no detectable organism is found) If no object is detected (i.e., the object is located within the second range), the object detection unit 2 outputs a signal indicating that no object is detected.

[0043] When the first output circuit 301 receives a signal from the detection unit 2 indicating that no object is detected, it outputs 0 (Low) as the first detection signal. This first detection signal is input to the base terminal of the first PNP transistor 305.

[0044] When the second output circuit 302 receives a signal from the detection unit 2 indicating that no object is detected, it outputs a second detection signal of 1 (High). This second detection signal is input to the base terminal of the second PNP transistor 306.

[0045] The first PNP transistor 305 receives the first detection signal (0) output from the first output circuit 301 as input to its base terminal. As a result, current flows from the base terminal towards the first output circuit 301, and also between the emitter and collector terminals. In other words, the first PNP transistor 305 becomes conductive. Therefore, the first output wire 313 outputs 1 as the first output signal, and the first output signal (1) is applied to the first load 307.

[0046] Since the second detection signal (1) output from the second output circuit 302 is input to the base terminal of the second PNP transistor 306, no current flows from the base terminal to the second output circuit 302, and no current flows between the emitter terminal and the collector terminal. In other words, the second PNP transistor 306 is in a non-conducting state. Therefore, the second load 308 is maintained in a state where 0 is applied.

[0047] The detection unit 309 acquires the state of the first load 307 (1 is applied) and the state of the second load 308 (0 is applied), and determines that there is no abnormality because the states of both loads are inverted from each other.

[0048] (2. If there is an internal abnormality in sensor 1) If there is an internal abnormality in sensor 1 (i.e., the detection level is within the abnormal operating range), the detection unit 2 outputs a signal indicating an internal abnormality, regardless of whether or not a detection object is present.

[0049] When the first output circuit 301 receives a signal from the detection unit 2 indicating an internal abnormality, it outputs 0 (Low) as the first detection signal. This first detection signal is input to the base terminal of the first PNP transistor 305.

[0050] When the second output circuit 302 receives a signal from the detection unit 2 indicating an internal abnormality, it outputs 0 (Low) as a second detection signal. This second detection signal is input to the base terminal of the second PNP transistor 306.

[0051] The first PNP transistor 305 receives the first detection signal (0) output from the first output circuit 301 as input to its base terminal. As a result, current flows from the base terminal to the first output circuit 301, and current also flows between the emitter terminal and the collector terminal. In other words, the first PNP transistor 305 becomes conductive. Therefore, the first output wire 313 outputs 1 as the first output signal, and the first output signal (1) is applied to the first load 307.

[0052] The second PNP transistor 306 receives the second detection signal (0) output from the second output circuit 302 as input to its base terminal. As a result, current flows from the base terminal towards the second output circuit 302, and also between the emitter and collector terminals. In other words, the second PNP transistor 306 becomes conductive. Therefore, the second output wire 314 outputs a second output signal of 1, and the second output signal (1) is applied to the second load 308.

[0053] The detection unit 309 acquires the state of the first load 307 (0 is applied) and the state of the second load 308 (0 is applied), and since both states are the same, it determines that there is an abnormality. This determination result is constant regardless of the presence or absence of a detection object.

[0054] (3. If there is no internal abnormality in sensor 1 and the power supply wiring 311 is broken) For example, if the power supply wiring 311 is broken at the location indicated by the symbol a in Figure 1, the power supply to the first PNP transistor 305 and the second PNP transistor 306 will be cut off. Therefore, in this case, regardless of the presence or absence of the detection body, both the first PNP transistor 305 and the second PNP transistor 306 will be in a non-conductive state, and the state of both the first load 307 and the second load 308 will remain in a state where 0 is applied. The detection unit 309 acquires the state of the first load 307 (0 applied) and the state of the second load 308 (0 applied), and since the states of both are the same, it determines that there is an abnormality.

[0055] (4. If there is no internal abnormality in sensor 1 and the ground wiring 312 is broken) For example, if the ground wiring 312 is broken at the location indicated by the symbol b in Figure 1, the power supply to the first PNP transistor 305 and the second PNP transistor 306 will be cut off. Therefore, in this case as well, regardless of the presence or absence of the detection body, both the first PNP transistor 305 and the second PNP transistor 306 will be in a non-conductive state, and the state of both the first load 307 and the second load 308 will remain in a state where 0 is applied. The detection unit 309 acquires the state of the first load 307 (0 applied) and the state of the second load 308 (0 applied), and since the states of both are the same, it determines that there is an abnormality.

[0056] (5. If there is no internal abnormality in sensor 1 and the first output wiring 313 is broken) For example, suppose the first output wiring 313 is broken at the location indicated by the symbol c in Figure 1.

[0057] (5-a. If a detection sample is present) If a detection object is present (i.e., the detection object is located within the first range), the detection object detection unit 2 outputs a signal indicating the presence of a detection object.

[0058] When the first output circuit 301 receives a signal from the detection unit 2 indicating the presence of a detection object, it outputs 1 as the first detection signal. Here, since the first output wiring 313 is broken at the location indicated by the symbol c in Figure 1, the state of the first load 307 does not change regardless of whether or not a detection object is present. Therefore, the first load 307 is maintained in a state where 0 is applied.

[0059] When the second output circuit 302 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 0 as a second detection signal. This second detection signal is input to the base terminal of the second PNP transistor 306.

[0060] The second PNP transistor 306 receives the second detection signal (0) output from the second output circuit 302 as input to its base terminal. As a result, current flows from the base terminal towards the second output circuit 302, and also between the emitter and collector terminals. In other words, the second PNP transistor 306 becomes conductive. Therefore, the second output wire 314 outputs a second output signal of 1, and the second output signal (1) is applied to the second load 308.

[0061] The detection unit 309 acquires the state of the first load 307 (0 is applied) and the state of the second load 308 (1 is applied). The detection unit 309 determines that there is no abnormality because the states of the two loads are inversely related. In other words, the detection unit 309 cannot determine that there is an abnormality even if the first output wiring 313 is broken, as long as there is a detected object. However, the detection unit 309 can determine that there is an abnormality when there is a change in the detection state of the detected object, that is, when the state changes from when there is a detected object to when there is no detected object.

[0062] (5-b. If no detection material is found) If no object is detected (i.e., the object is located within the second range), the object detection unit 2 outputs a signal indicating that no object is detected.

[0063] When the first output circuit 301 receives a signal from the detection unit 2 indicating the absence of a detection object, it outputs 0 as the first detection signal. Here, since the first output wiring 313 is broken at the location indicated by the symbol c in Figure 1, the state of the first load 307 does not change regardless of the presence or absence of a detection object. Therefore, the first load 307 is maintained in a state where 0 is applied.

[0064] When the second output circuit 302 receives a signal from the detection unit 2 indicating that no object is detected, it outputs a second detection signal of 1. This second detection signal is input to the base terminal of the second PNP transistor 306.

[0065] Since the second detection signal (1) output from the second output circuit 302 is input to the base terminal of the second PNP transistor 306, no current flows from the base terminal to the second output circuit 302, and no current flows between the emitter terminal and the collector terminal. In other words, the second PNP transistor 306 is in a non-conducting state. Therefore, the second load 308 is maintained in a state where 0 is applied.

[0066] The detection unit 309 acquires the state of the first load 307 (0 is applied) and the state of the second load 308 (0 is applied), and since the states of both loads are the same, it determines that there is an abnormality.

[0067] Normally, the detection state of the detected object by sensor 1 (detection unit 2) is expected to change continuously. Therefore, even if the detection unit 309 initially determines that there is no abnormality, it can quickly detect an abnormality (determine that there is an abnormality) if the detection state of the detected object changes afterward.

[0068] (6. If there is no internal abnormality in sensor 1 and the second output wiring 314 is broken) For example, suppose the second output wiring 314 is broken at the location indicated by the symbol d in Figure 1.

[0069] (6. If no detection is found) If no object is detected (i.e., the object is located within the second range), the object detection unit 2 outputs a signal indicating that no object is detected.

[0070] When the first output circuit 301 receives a signal from the object detection unit 2 indicating that no object is detected, it outputs 0 as the first detection signal. This first detection signal is input to the base terminal of the first PNP transistor 305.

[0071] The first PNP transistor 305 receives the first detection signal (0) output from the first output circuit 301 as input to its base terminal. As a result, current flows from the base terminal towards the first output circuit 301, and also between the emitter and collector terminals. In other words, the first PNP transistor 305 becomes conductive. Therefore, the first output wire 313 outputs 1 as the first output signal, and the first output signal (1) is applied to the first load 307.

[0072] When the second output circuit 302 receives a signal from the detection unit 2 indicating the absence of a detection object, it outputs 1 as the second detection signal. Here, since the second output wiring 314 is broken at the location indicated by the symbol d in Figure 1, the state of the second load 308 does not change regardless of the presence or absence of a detection object. Therefore, the second load 308 is maintained in a state where 0 is applied.

[0073] The detection unit 309 acquires the state of the first load 307 (1 is applied) and the state of the second load 308 (0 is applied). The detection unit 309 determines that there is no abnormality because the states of both loads are inversely related. In other words, the detection unit 309 cannot determine that there is an abnormality even if the second output wiring 314 is disconnected, as long as there is a detected object. However, the detection unit 309 can determine that there is an abnormality when there is a change in the detection state of the detected object, that is, when the state changes from one without a detected object to one with a detected object.

[0074] (6-b. If a detectable substance is present) If a detection object is present (i.e., the detection object is located within the first range), the detection object detection unit 2 outputs a signal indicating the presence of a detection object.

[0075] When the first output circuit 301 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 1 as the first detection signal. This first detection signal is input to the base terminal of the first PNP transistor 305.

[0076] Since the first detection signal (1) output from the first output circuit 301 is input to the base terminal of the first PNP transistor 305, no current flows from the base terminal to the first output circuit 301, and no current flows between the emitter terminal and the collector terminal. In other words, the first PNP transistor 305 is in a non-conducting state. Therefore, the first load 307 is maintained in a state where 0 is applied.

[0077] When the second output circuit 302 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 0 as the second detection signal. Here, since the second output wiring 314 is broken at the location indicated by the symbol d in Figure 1, the state of the second load 308 does not change regardless of whether or not a detected object is present. Therefore, the second load 308 is maintained in a state where 0 is applied.

[0078] The detection unit 309 acquires the state of the first load 307 (0 indicates applied) and the state of the second load 308 (0 indicates applied). Since the states of both loads are the same, the detection unit 309 determines that there is an abnormality.

[0079] (7. If there is no internal abnormality in sensor 1 and the power supply wiring 311 and the ground wiring 312 are short-circuited) For example, suppose that the power supply wiring 311 and the ground wiring 312 are short-circuited between symbols a and b. In this case, the power supply to the first PNP transistor 305 and the second PNP transistor 306 is stopped. Therefore, in this case, regardless of the presence or absence of the detection body, both the first PNP transistor 305 and the second PNP transistor 306 become non-conductive, and the state of both the first load 307 and the second load 308 is maintained as if a value of 0 were applied. The detection unit 309 acquires the state of the first load 307 (a value of 0 applied) and the state of the second load 308 (a value of 0 applied), and since the states of both are the same, it determines that there is an abnormality.

[0080] (8. If there is no internal abnormality in sensor 1 and the power supply wiring 311 and the first output wiring 313 are short-circuited) For example, assume that the power supply wiring 311 and the first output wiring 313 are short-circuited between the sign ac.

[0081] (8. If no detection is found) If no object is detected (i.e., the object is located within the second range), the object detection unit 2 outputs a signal indicating that no object is detected.

[0082] When the first output circuit 301 receives a signal from the detection unit 2 indicating the absence of a detection object, it outputs 0 as the first detection signal. Here, since the power supply wiring 311 and the first output wiring 313 are short-circuited between the signs ac, the potential between signs ac is the same regardless of whether a detection object is present or not. Therefore, the signal (1) from the positive terminal of the power supply 304 is output to the first output wiring 313 via the power supply wiring 311, and 1 is applied to the first load 307.

[0083] When the second output circuit 302 receives a signal from the detection unit 2 indicating that no object is detected, it outputs a second detection signal of 1. This second detection signal is input to the base terminal of the second PNP transistor 306.

[0084] Since the second detection signal (1) output from the second output circuit 302 is input to the base terminal of the second PNP transistor 306, no current flows from the base terminal to the second output circuit 302, and no current flows between the emitter terminal and the collector terminal. In other words, the second PNP transistor 306 is in a non-conducting state. Therefore, the second load 308 is maintained in a state where 0 is applied.

[0085] The detection unit 309 acquires the state of the first load 307 (1 applied) and the state of the second load 308 (0 applied), and since the states of both loads are reversed, it determines that there is no abnormality. In other words, when there is no object to detect, the detection unit 309 cannot determine that there is an abnormality even if the power supply wiring 311 and the first output wiring 313 are short-circuited between codes ac. However, the detection unit 309 can determine that there is an abnormality when there is a change in the detection state, that is, when the state changes from a state with no object to a state with an object to detect.

[0086] (8-b. If a detection sample is present) If a detection object is present (i.e., the detection object is located within the first range), the detection object detection unit 2 outputs a signal indicating the presence of a detection object.

[0087] When the first output circuit 301 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 1 as the first detection signal. Here, since the power supply wiring 311 and the first output wiring 313 are short-circuited between symbols ac, the potential between symbols ac is the same regardless of whether or not a detected object is present. Therefore, the signal (1) from the positive terminal of the power supply 304 is output to the first output wiring 313 via the power supply wiring 311, and 1 is applied to the first load 307.

[0088] When the second output circuit 302 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 0 as a second detection signal. This second detection signal is input to the base terminal of the second PNP transistor 306.

[0089] The second PNP transistor 306 receives the second detection signal (0) output from the second output circuit 302 as input to its base terminal. As a result, current flows from the base terminal towards the second output circuit 302, and also between the emitter and collector terminals. In other words, the second PNP transistor 306 becomes conductive. Therefore, the second output wire 314 outputs a second output signal of 1, and the second output signal (1) is applied to the second load 308.

[0090] The detection unit 309 acquires the state of the first load 307 (1 applied) and the state of the second load 308 (1 applied), and since the states of both loads are the same, it determines that there is an abnormality.

[0091] (9. If there is no internal abnormality in sensor 1 and the power supply wiring 311 and the second output wiring 314 are short-circuited) For example, assume that the power supply wiring 311 and the second output wiring 314 are short-circuited between symbols ad and ad.

[0092] (9-a. If a substance is detected) If a detection object is present (i.e., the detection object is located within the first range), the detection object detection unit 2 outputs a signal indicating the presence of a detection object.

[0093] When the first output circuit 301 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 1 as the first detection signal. This first detection signal is input to the base terminal of the first PNP transistor 305.

[0094] Since the first detection signal (1) output from the first output circuit 301 is input to the base terminal of the first PNP transistor 305, no current flows from the base terminal to the first output circuit 301, and no current flows between the emitter terminal and the collector terminal. In other words, the first PNP transistor 305 is in a non-conducting state. Therefore, the first load 307 is maintained in a state where 0 is applied.

[0095] When the second output circuit 302 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 0 as the second detection signal. Here, since the power supply wiring 311 and the second output wiring 314 are short-circuited between symbols a and b, the potential between symbols a and b is the same regardless of whether or not a detected object is present. Therefore, the signal (1) from the positive terminal of the power supply 304 is output to the second output wiring 314 via the power supply wiring 311, and a value of 1 is applied to the second load 308.

[0096] The detection unit 309 acquires the state of the first load 307 (0 applied) and the state of the second load 308 (1 applied), and since the states of both loads are inversely related, it determines that there is no abnormality. In other words, when a detection object is present, the detection unit 309 cannot determine that there is an abnormality even if the power supply wiring 311 and the second output wiring 314 are short-circuited between symbols a and b. However, the detection unit 309 can determine that there is an abnormality when there is a change in the detection state, that is, when the state changes from when a detection object is present to when there is no detection object.

[0097] (9-b. If no detection material is found) If no object is detected (i.e., the object is located within the second range), the object detection unit 2 outputs a signal indicating that no object is detected.

[0098] When the first output circuit 301 receives a signal from the object detection unit 2 indicating that no object is detected, it outputs 0 as the first detection signal. This first detection signal is input to the base terminal of the first PNP transistor 305.

[0099] The first PNP transistor 305 receives the first detection signal (0) output from the first output circuit 301 as input to its base terminal. As a result, current flows from the base terminal towards the first output circuit 301, and also between the emitter and collector terminals. In other words, the first PNP transistor 305 becomes conductive. Therefore, the first output wire 313 outputs 1 as the first output signal, and the first output signal (1) is applied to the first load 307.

[0100] When the second output circuit 302 receives a signal from the detection unit 2 indicating the absence of a detection object, it outputs 1 as the second detection signal. Here, since the power supply wiring 311 and the second output wiring 314 are short-circuited between symbols a and b, the potential between symbols a and b is the same regardless of whether a detection object is present or not. Therefore, the signal (1) from the positive terminal of the power supply 304 is output to the second output wiring 314 via the power supply wiring 311, and 1 is applied to the second load 308.

[0101] The detection unit 309 acquires the state of the first load 307 (1 applied) and the state of the second load 308 (1 applied), and since the states of both loads are the same, it determines that there is an abnormality.

[0102] (10. If there is no internal abnormality in sensor 1 and the first output wiring 313 and the second output wiring 314 are short-circuited) For example, assume that the first output wiring 313 and the second output wiring 314 are short-circuited between the symbols cd.

[0103] (10-a. If a detection sample is present) If a detection object is present (i.e., the detection object is located within the first range), the detection object detection unit 2 outputs a signal indicating the presence of a detection object.

[0104] When the first output circuit 301 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 1 as the first detection signal. This first detection signal is input to the base terminal of the first PNP transistor 305.

[0105] When the second output circuit 302 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 0 as a second detection signal. This second detection signal is input to the base terminal of the second PNP transistor 306.

[0106] The second PNP transistor 306 receives the second detection signal (0) output from the second output circuit 302 as input to its base terminal. As a result, current flows from the base terminal towards the second output circuit 302, and also between the emitter and collector terminals. In other words, the second PNP transistor 306 becomes conductive. Therefore, the second output wire 314 outputs a second output signal of 1, and the second output signal (1) is applied to the second load 308.

[0107] Here, since the first output wiring 313 and the second output wiring 314 are short-circuited between the signs cd, the potential between signs cd is the same. Therefore, the second output signal (1) is output from the second output wiring 314 to the first output wiring 313 regardless of whether a detection object is present or not. As a result, the second output signal (1) is applied to the first load 307.

[0108] The detection unit 309 acquires the state of the first load 307 (1 applied) and the state of the second load 308 (1 applied). Since the states of both loads are the same, the detection unit 309 determines that there is an abnormality.

[0109] (10-b. If no detectable organism is found) If no object is detected (i.e., the object is located within the second range), the object detection unit 2 outputs a signal indicating that no object is detected.

[0110] When the first output circuit 301 receives a signal from the object detection unit 2 indicating that no object is detected, it outputs 0 as the first detection signal. This first detection signal is input to the base terminal of the first PNP transistor 305.

[0111] When the second output circuit 302 receives a signal from the detection unit 2 indicating that no object is detected, it outputs a second detection signal of 1. This second detection signal is input to the base terminal of the second PNP transistor 306.

[0112] The first PNP transistor 305 receives the second detection signal (0) output from the first output circuit 301 as input to its base terminal. As a result, current flows from the base terminal towards the first output circuit 301, and also between the emitter and collector terminals. In other words, the first PNP transistor 305 becomes conductive. Therefore, the first output wire 313 outputs 1 as the first output signal, and the first output signal (1) is applied to the first load 307.

[0113] Here, since the first output wiring 313 and the second output wiring 314 are short-circuited between the signs cd, the potential between signs cd is the same. Therefore, the first output signal (1) is output from the first output wiring 313 to the second output wiring 314 regardless of whether a detection object is present or not. As a result, the first output signal (1) is applied to the second load 308.

[0114] The detection unit 309 acquires the state of the first load 307 (1 applied) and the state of the second load 308 (1 applied). Since the states of both loads are the same, the detection unit 309 determines that there is an abnormality.

[0115] (11. If there is no internal abnormality in sensor 1 and the first output wiring 313 and the ground wiring 312 are short-circuited) For example, assume that the first output wiring 313 and the ground wiring 312 are short-circuited between the signs cb.

[0116] (11-a. If a detection sample is present) If a detection object is present (i.e., the detection object is located within the first range), the detection object detection unit 2 outputs a signal indicating the presence of a detection object.

[0117] When the first output circuit 301 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs a first detection signal of 1. This first detection signal is input to the base terminal of the first PNP transistor 305. Here, since the first output wiring 313 and the ground wiring 312 are short-circuited between the signs cb, the potential between signs cb is the same regardless of whether or not a detected object is present. As a result, the first load 307 is maintained in a state where 0 is applied.

[0118] When the second output circuit 302 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 0 as a second detection signal. This second detection signal is input to the base terminal of the second PNP transistor 306.

[0119] The second PNP transistor 306 receives the second detection signal (0) output from the second output circuit 302 as input to its base terminal. As a result, current flows from the base terminal towards the second output circuit 302, and also between the emitter and collector terminals. In other words, the second PNP transistor 306 becomes conductive. Therefore, the second output wire 314 outputs a second output signal of 1, and the second output signal (1) is applied to the second load 308.

[0120] The detection unit 309 acquires the state of the first load 307 (0 applied) and the state of the second load 308 (1 applied), and since the states of both loads are inversely related, it determines that there is no abnormality. In other words, when a detection object is present, the detection unit 309 cannot determine that there is an abnormality even if the first output wiring 313 and the ground wiring 312 are short-circuited between the symbols cb. However, the detection unit 309 can determine that there is an abnormality when there is a change in the detection state, that is, when the state changes from when a detection object is present to when there is no detection object.

[0121] (11-b. If no detection is found) If no object is detected (i.e., the object is located within the second range), the object detection unit 2 outputs a signal indicating that no object is detected.

[0122] When the first output circuit 301 receives a signal from the detection unit 2 indicating the absence of a detection object, it outputs 0 as the first detection signal. Here, since the first output wiring 313 and the ground wiring 312 are short-circuited between the signs cb, the potential between signs cb is the same regardless of whether a detection object is present or not. As a result, the first load 307 is maintained in a state where 0 is applied.

[0123] When the second output circuit 302 receives a signal from the detection unit 2 indicating that no object is detected, it outputs a second detection signal of 1. This signal is input to the base terminal of the second PNP transistor 306.

[0124] Since the second detection signal (1) output from the second output circuit 302 is input to the base terminal of the second PNP transistor 306, no current flows from the base terminal to the second output circuit 302, and no current flows between the emitter terminal and the collector terminal. In other words, the second PNP transistor 306 is in a non-conducting state. Therefore, the second load 308 is maintained in a state where 0 is applied.

[0125] The detection unit 309 acquires the state of the first load 307 (0 is applied) and the state of the second load 308 (0 is applied), and since the states of both loads are the same, it determines that there is an abnormality.

[0126] (12. If there is no internal abnormality in sensor 1 and the second output wiring 314 and the ground wiring 312 are short-circuited) For example, assume that the second output wire 314 and the ground wire 312 are short-circuited between the sign dB values.

[0127] (12-a. If no detection is found) If no object is detected (i.e., the object is located within the second range), the object detection unit 2 outputs a signal indicating that no object is detected.

[0128] When the first output circuit 301 receives a signal from the object detection unit 2 indicating that no object is detected, it outputs 0 as the first detection signal. This first detection signal is input to the base terminal of the first PNP transistor 305.

[0129] The first PNP transistor 305 receives the first detection signal (0) output from the first output circuit 301 as input to its base terminal. As a result, current flows from the base terminal towards the first output circuit 301, and also between the emitter and collector terminals. In other words, the first PNP transistor 305 becomes conductive. Therefore, the first output wire 313 outputs 1 as the first output signal, and the first output signal (1) is applied to the first load 307.

[0130] When the second output circuit 302 receives a signal from the detection unit 2 indicating the absence of a detection object, it outputs 1 as the second detection signal. Here, since the second output wiring 314 and the ground wiring 312 are short-circuited between the sign dB values, the potential between the sign dB values ​​is the same regardless of whether a detection object is present or not. As a result, the second load 308 is maintained in a state where 0 is applied.

[0131] The detection unit 309 acquires the state of the first load 307 (1 applied) and the state of the second load 308 (0 applied). Since the states of the two loads are different, the detection unit 309 determines that there is no abnormality. In other words, when there is no object to detect, the detection unit 309 cannot determine that there is an abnormality even if the second output wiring 314 and the ground wiring 312 are short-circuited between the values ​​dB. However, the detection unit 309 can determine that there is an abnormality when there is a change in the detection state, that is, when the state changes from a state with no object to a state with an object to detect.

[0132] (12-b. If a detection sample is present) If a detection object is present (i.e., the detection object is located within the first range), the detection object detection unit 2 outputs a signal indicating the presence of a detection object.

[0133] When the first output circuit 301 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 1 as the first detection signal. This first detection signal is input to the base terminal of the first PNP transistor 305.

[0134] Since the first detection signal (1) output from the first output circuit 301 is input to the base terminal of the first PNP transistor 305, no current flows from the base terminal to the first output circuit 301, and no current flows between the emitter terminal and the collector terminal. In other words, the first PNP transistor 305 is in a non-conducting state. Therefore, the first load 307 is maintained in a state where 0 is applied.

[0135] When the second output circuit 302 receives a signal from the detection unit 2 indicating the presence of a detected object, it outputs 0 as the second detection signal. Here, since the second output wiring 314 and the ground wiring 312 are short-circuited between the sign dB values, the potential between the sign dB values ​​is the same regardless of whether or not a detected object is present. As a result, the second load 308 is maintained in a state where 0 is applied.

[0136] The detection unit 309 acquires the state of the first load 307 (0 is applied) and the state of the second load 308 (0 is applied), and since the states of both loads are the same, it determines that there is an abnormality.

[0137] As described above, the abnormality detection device 3 can detect wiring abnormalities (open circuit or short circuit) and internal abnormalities of the sensor 1 based on the states of the first load 307 and the second load 308. If a wiring abnormality and an internal abnormality occur simultaneously, it is expected that a state indicating a wiring abnormality will appear in the first load 307 and the second load 308. Therefore, even if a wiring abnormality and an internal abnormality occur simultaneously, the detection unit 309 can detect the abnormality based on the states of the first load 307 and the second load 308.

[0138] In the above example, the first output circuit 301 outputs 1 (High) as the first detection signal when the detection unit 2 detects that the detection object is located within the first range of the normal operating range (i.e., the presence of a detection object), and outputs 0 (Low) as the first detection signal when it detects that the detection object is not located within the first range of the normal operating range. However, conversely, the first output circuit 301 may also output 0 as the first detection signal in the former case and 1 as the first detection signal in the latter case.

[0139] Similarly, the above description explains an example in which the second output circuit 302 outputs 1 (High) as the second detection signal when the detection unit 2 detects that the detection object is located in the second range within the normal operating range (i.e., there is no detection object), and outputs 0 (Low) as the second detection signal when it detects that the detection object is not located in the second range within the normal operating range. However, conversely, the second output circuit 302 may output 0 as the second detection signal in the former case and 1 as the second detection signal in the latter case. In these cases, one can simply replace signal (1) with signal (0) and signal (0) with signal (1) in Figure 2.

[0140] Furthermore, although the above description explains an example in which both the first switching element 305 and the second switching element 306 are composed of PNP transistors, the first switching element 305 and the second switching element 306 are not limited to this and may be composed of, for example, P-channel type field-effect transistors.

[0141] Furthermore, the first switching element 305 and the second switching element 306 may be composed of an NPN transistor or an N-channel field-effect transistor. If the first switching element 305 and the second switching element 306 are composed of an NPN transistor or an N-channel field-effect transistor, the abnormality detection device 3 only needs to have the arrangement of the power supply wiring 311, to which the positive terminal of the power supply 304 is connected, and the ground wiring 312, to which the negative terminal of the power supply 304 is connected, reversed in the configuration shown in Figure 1.

[0142] In this case, the first switching element 305 has one end connected to the ground wiring 312 and the other end connected to one end of the first output wiring 313, and switches its conduction state in accordance with the first detection signal output by the first output circuit 301. The second switching element 306 has one end connected to the ground wiring 312 and the other end connected to one end of the second output wiring 314, and switches its conduction state in accordance with the second detection signal output by the second output circuit 302. The first load 307 has one end connected to the other end of the first output wiring 313 and the other end connected to the power supply wiring 311. The second load 308 has one end connected to the other end of the second output wiring 314 and the other end connected to the power supply wiring 311.

[0143] Even with this configuration, the abnormality detection device 3 operates in the same way as when the first switching element 305 and the second switching element 306 are composed of PNP transistors, and can detect wiring abnormalities (open circuit or short circuit) and internal abnormalities of the sensor 1 based on the state of the first load 307 and the second load 308.

[0144] As described above, according to Embodiment 1, the abnormality detection device 3 includes: a first output circuit 301 that outputs a first detection signal indicating whether or not the detected object is located in a first range within the normal operating range based on the detection result from the sensor 1; a second output circuit 302 that outputs a second detection signal indicating whether or not the detected object is located in a second range different from the first range within the normal operating range based on the detection result from the sensor 1; a power supply 304 with its positive terminal connected to the power supply wiring 311 and its negative terminal connected to the ground wiring 312; and a first switching element with one end connected to the power supply wiring 311 and the other end connected to one end of the first output wiring 313, which switches its conduction state in accordance with the first detection signal output by the first output circuit 301. The abnormality detection device 3 comprises: 305; a second switching element 306, one end of which is connected to the power supply wiring 311 and the other end of which is connected to one end of the second output wiring 314, and which switches its conduction state in accordance with a second detection signal output by the second output circuit 302; a first load 307, one end of which is connected to the other end of the first output wiring 313 and the other end of which is connected to the ground wiring 312; a second load 308, one end of which is connected to the other end of the second output wiring 314 and the other end of which is connected to the ground wiring 312; and a detection unit 309 that detects at least one of abnormalities in the power supply wiring 311, the first output wiring 313, the second output wiring 314, and the ground wiring 312, as well as an internal abnormality of the sensor 1, based on the state of the first load 307 and the state of the second load 308.

[0145] Furthermore, the abnormality detection device 3 includes a first output circuit 301 that outputs a first detection signal indicating whether the detected object is located in a first range within the normal operating range based on the detection result from the sensor 1, a second output circuit 302 that outputs a second detection signal indicating whether the detected object is located in a second range different from the first range within the normal operating range based on the detection result from the sensor 1, a power supply 304 with its positive terminal connected to the power supply wiring 311 and its negative terminal connected to the ground wiring 312, and a first switching element 305 with one end connected to the ground wiring 312 and the other end connected to one end of the first output wiring 313, which switches its conduction state according to the first detection signal output by the first output circuit 301, and The abnormality detection device 3 includes a second switching element 306, one end of which is connected to the ground wiring 312 and the other end of which is connected to one end of the second output wiring 314, and which switches its conduction state in accordance with the second detection signal output by the second output circuit 302; a first load 307, one end of which is connected to the other end of the first output wiring 313 and the other end of which is connected to the power supply wiring 311; a second load 308, one end of which is connected to the other end of the second output wiring 314 and the other end of which is connected to the power supply wiring 313 and the other end of which is connected to the ground wiring 314 and the ground wiring 312, and an internal abnormality of the sensor 1, based on the state of the first load 307 and the state of the second load 308.

[0146] Furthermore, the detection unit 309 detects at least one of the following when the state of the first load 307 and the state of the second load 308 are the same: an abnormality in the power supply wiring 311, the first output wiring 313, the second output wiring 314, and the ground wiring 312, as well as an internal abnormality in the sensor 1. As a result, the abnormality detection device 3 can accurately detect abnormalities based on the states of the first load 307 and the second load 308.

[0147] Furthermore, the detection unit 309 detects abnormalities in the power supply wiring 311, the first output wiring 313, the second output wiring 314, and the ground wiring 312 when the state of the first load 307 and the state of the second load 308 change from an inverted state to the same state, depending on whether the detected object is located within the first or second range. As a result, the abnormality detection device 3 can accurately detect wiring abnormalities based on the state changes of the first load 307 and the second load 308.

[0148] Furthermore, within the scope of the present invention, any component of the embodiment can be modified, or any component can be omitted in the embodiment. [Explanation of symbols]

[0149] 1 sensor 2. Detector Unit 3. Anomaly detection device 301 First output circuit 302 Second output circuit 304 Power supply 305 First switching element (first PNP transistor) 306 Second switching element (second PNP transistor) 307 First load 308 Second load 309 Detection unit 311 Power wiring 312 Ground wiring 313 First output wiring 314 Second output wiring

Claims

1. a first output circuit that outputs a first detection signal indicating whether or not the detected object is located within a first range within the normal operating range based on the detection result by the sensor; a second output circuit that outputs a second detection signal indicating whether the detected object is located in a second range that is different from a first range within the normal operating range, based on the detection result by the sensor; a power supply whose positive terminal is connected to the power supply wiring and whose negative terminal is connected to the ground wiring; a first switching element having one end connected to the power supply wiring and the other end connected to one end of a first output wiring, and switching a conduction state in response to a first detection signal output by the first output circuit; a second switching element having one end connected to the power supply wiring and the other end connected to one end of a second output wiring, and switching a conduction state in response to a second detection signal output by the second output circuit; a first load having one end connected to the other end of the first output wiring and the other end connected to the ground wiring; a second load having one end connected to the other end of the second output wiring and the other end connected to the ground wiring; a detection unit that detects at least one of an abnormality in the power supply wiring, the first output wiring, the second output wiring, and the ground wiring, and an internal abnormality of the sensor, based on a state of the first load and a state of the second load; An anomaly detection device equipped with the

2. a first output circuit that outputs a first detection signal indicating whether or not the detected object is located within a first range within the normal operating range based on the detection result by the sensor; a second output circuit that outputs a second detection signal indicating whether the detected object is located in a second range that is different from a first range within the normal operating range, based on the detection result by the sensor; a power supply whose positive terminal is connected to the power supply wiring and whose negative terminal is connected to the ground wiring; a first switching element having one end connected to the ground wiring and the other end connected to one end of a first output wiring, and switching a conduction state in response to a first detection signal output by the first output circuit; a second switching element having one end connected to the ground wiring and the other end connected to one end of a second output wiring, and switching a conduction state in response to a second detection signal output by the second output circuit; a first load having one end connected to the other end of the first output wiring and the other end connected to the power supply wiring; a second load having one end connected to the other end of the second output wiring and the other end connected to the power supply wiring; a detection unit that detects at least one of an abnormality in the power supply wiring, the first output wiring, the second output wiring, and the ground wiring, and an internal abnormality of the sensor, based on a state of the first load and a state of the second load; An anomaly detection device equipped with the

3. The detection unit 3. The abnormality detection device according to claim 1, wherein when the state of the first load and the state of the second load are the same, the device detects at least one of an abnormality in the power supply wiring, the first output wiring, the second output wiring, and the ground wiring, and an internal abnormality in the sensor.

4. The detection unit 4. The abnormality detection device according to claim 1, wherein the abnormality detection device detects an abnormality in the power supply wiring, the first output wiring, the second output wiring, and the ground wiring when the state of the first load and the state of the second load change from mutually inverted states to the same state depending on whether the detection object is located in the first range or the second range.

5. A sensor, A sensor system comprising the anomaly detection device according to any one of claims 1 to 4.

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