Sensor and robot with the same

Abstract

To provide a sensor capable of detecting a detection target object with a high precision.SOLUTION: The sensor includes: a detection electrode provided to extend along a detection direction perpendicular to a detection surface for detecting a detection object; a correction electrode provided to extend along the detection direction in parallel with the detection electrode; a signal generation circuit configured to generate a detection signal and to transmit the generated detection signal to the detection electrode; and a detection circuit configured to detect the detection object according to a potential of the detection electrode.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a sensor and a robot equipped with the sensor. [Background technology]

[0002] 2. Description of the Related Art Conventionally, robots equipped with sensors for detecting objects have been known.

[0003] In this regard, Patent Document 1 discloses a sensor that detects approach or contact with another object, in which an electrode portion is formed on the outer surface or inner surface of an exterior member of a movable device such as a robot. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-89165 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the technology described in Patent Document 1 has a problem in that the capacitance is easily affected by changes in temperature and humidity of the air between the object to be detected and the sensor, making it impossible to detect the approach of the object to be detected with high accuracy.

[0006] The present invention has been made in view of the above problems, and its object is to provide a sensor that can detect an object with high accuracy, and a robot equipped with the sensor. [Means for solving the problem]

[0007] In order to solve the above problem, the sensor of the present invention comprises a detection electrode arranged to extend along a detection direction perpendicular to a detection surface for detecting a detected object, a correction electrode arranged to extend along the detection direction in parallel with the detection electrode, a signal generation circuit that generates a detection signal and transmits the generated detection signal to the detection electrode, and a detection circuit that detects the detected object in accordance with the potential of the detection electrode.

[0008] In addition, the detection electrode is formed so that at least a portion of the detection electrode is curved or bent in a direction perpendicular to the detection direction, and the correction electrode is formed so that at least a portion of the detection electrode is curved or bent in the same direction as the curvature or bending direction of the detection electrode.

[0009] The device further includes an active shield electrode that is arranged in parallel with the detection electrode and the correction electrode to extend along the detection direction and is supplied with a signal of the same potential as the detection signal, and the detection electrode is arranged to the right of the correction electrode along the detection direction, and the active shield electrode is arranged to the right of the detection electrode along the detection direction.

[0010] The detection electrodes and correction electrodes are provided in plural such that at least some of their positions in the detection direction are equally spaced from each other between adjacent electrodes.

[0011] In addition, the sensor of the present invention has two operating modes, a correction mode and a detection mode, and further includes a control circuit that controls the operation of the detection circuit so that the capacitance between the detection electrode and the correction electrode is detected when the operating mode is the correction mode, and the object to be detected when the operating mode is the detection mode.

[0012] The robot of the present invention also includes a sensor having a detection electrode extending along a detection direction perpendicular to a detection surface for detecting an object to be detected, a correction electrode extending along the detection direction in parallel to the detection electrode, a signal generation circuit that generates a detection signal and transmits the generated detection signal to the detection electrode, and a detection circuit that detects the object to be detected in accordance with the potential of the detection electrode, a movable arm on which the sensor is provided, and a wrist connected to the arm for performing work on a workpiece. [Effects of the Invention]

[0013] According to the present invention, a sensor and a robot equipped with the sensor can detect an object with high accuracy. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a diagram showing the configuration of a robot equipped with a sensor according to an embodiment of the present invention; [Figure 2] FIG. 2 is a diagram showing details of the configuration of the sensor shown in FIG. [Figure 3] 2A and 2B are diagrams illustrating the operation of the sensor shown in FIG. 1 when the operation mode of the sensor is a correction mode. [Figure 4A] 3 is a diagram showing a second example of the electrodes of the sensor shown in FIG. 2. FIG. [Figure 4B] 2. FIG. 4 is a diagram showing a third example of the electrodes of the sensor shown in FIG. [Figure 4C] 2. FIG. 4 is a diagram showing a fourth example of the electrodes of the sensor shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described with reference to the accompanying drawings. To facilitate understanding of the description, the same components and steps in each drawing will be designated by the same reference numerals as much as possible, and redundant description will be omitted.

[0016] FIG. 1 is a diagram showing the configuration of a robot 1 equipped with a sensor according to this embodiment. The robot 1 is an industrial device having a movable part that can move within a space within a predetermined distance from the robot 1, such as a robot with an articulated arm, a machine tool, or a tester. In this embodiment, a case will be described in which the robot 1 is a robot with an articulated arm. As shown in FIG. 1, the main parts of the robot 1 include, for example, a sensor 10, an arm unit 20, a base unit 30, a wrist unit 40, and a control device 50.

[0017] The sensor 10 is, for example, a capacitance-type proximity sensor that detects the presence or absence of an object in a space in a detection direction. Specifically, the sensor 10 detects changes in capacitance in the space using multiple detection electrodes arranged along a detection surface perpendicular to the detection direction. The sensor 10 detects the presence or absence of an object according to the detected changes in capacitance. The sensor 10 is provided on the surface of the arm unit 20 at or near the tip of the arm unit.

[0018] The arm unit 20 is, for example, an articulated arm, and its main part is made up of multiple arms and multiple drive units. The base end of the arm unit 20 is connected to the base unit 30, and the tip end is connected to the wrist unit 40. The arm unit 20 has a sensor 10 provided on the surface of the arm at or near the tip end.

[0019] The base unit 30 is a base for supporting the arm unit 20, and is installed so as to be in contact with an installation surface (not shown) of the robot 1. The base unit 30 is connected to the arm unit 20. The base unit 30 is also connected to the control device 50 so as to be able to communicate with it.

[0020] The wrist 40 is connected to the tip of the arm 20 and performs various operations on a workpiece (not shown). The various operations include, for example, irradiation with X-rays, gripping, transporting, rotating, attaching to another workpiece, injecting or applying substances, polishing, screwing, heating, etc.

[0021] The control device 50 is configured to be able to communicate with the base unit 30 and transmits control commands to the base unit 30 to control the operation. The control device 50 may transmit control commands directly to the sensor 10, arm unit 20, and wrist unit 40 without going through the base unit 30. The control device 50 also acquires various information related to the sensor 10, arm unit 20, and wrist unit 40 from the base unit 30 and stores the acquired information. The control device 50 reflects the stored information in controlling the operation of the arm unit 20 and wrist unit 40, and notifies the administrator or user of the robot 1 by screen display, audio output, etc.

[0022] The configuration of the robot 1 has been described above. Next, the sensor 10 will be described with reference to FIG. 2. FIG. 2 is a diagram showing the details of the configuration of the sensor 10 shown in FIG. 1. In FIG. 2, the direction perpendicular to the detection surface S of the sensor 10 is defined as the detection direction Y. Furthermore, the direction parallel to the detection surface S and perpendicular to the detection direction Y is defined as the direction X. Furthermore, the space that extends from the detection surface S toward the detection direction Y and is the target of detection of the detection object 2 by the sensor 10 is defined as the detection space AREA. Note that in FIG. 2, the detection object 2 is a person, but is not limited to this and may be any object.

[0023] 2, the sensor 10 includes, as its main part, a plurality of detection electrodes 11, a plurality of correction electrodes 12, an active shield electrode 13, a signal generating circuit 14, a detection circuit 15, and a control circuit 16. The sensor 10 also includes, as its main part, resistance elements R0 to R2, a short-circuit control element SW, buffer circuits BUF1 and BUF2, and a capacitance element C0.

[0024] The detection electrode 11, correction electrode 12, and active shield electrode 13 are electrodes formed of a metal such as copper. The detection electrode 11 detects a change in the capacitance Cx of the detection space AREA in response to a detection signal S0 transmitted from a signal generating circuit 14 via a resistive element R0, and transmits the detected change as an electrical signal to an amplifier circuit AMP of the detection circuit 15. The detection electrode 11 is connected to the other end of the resistive element R0 and a non-inverting input terminal + of the amplifier circuit AMP.

[0025] The detection electrode 11 is provided on the sensor 10 so as to extend along a detection direction Y perpendicular to the detection surface S according to the capacitance Cx of the detection space AREA. The detection electrode 11 is formed so that at least a portion of the detection electrode 11 is curved toward a direction X perpendicular to the detection direction Y. Specifically, the detection electrode 11 is formed in a crescent shape that extends along the detection direction Y and curves toward the direction X. That is, the detection electrode 11 is formed so that, for example, the center of the detection electrode 11 is thicker than the tip in the detection direction Y. The size of the detection electrode 11 is, for example, about 5 mm in length in the detection direction Y, about 1 mm at most in thickness in the direction X, and about 1 mm to 5 mm in depth. A plurality of detection electrodes 11 are provided along the direction X.

[0026] The correction electrode 12 is an electrode for detecting the capacitance of the detection space AREA when no object 2 is present. The correction electrode 12 is connected to the other end of the short-circuit control element SW, and when both ends of the short-circuit control element SW are conductive, a reference potential GND is supplied to the correction electrode 12 via the short-circuit control element SW. When the reference potential GND is supplied to the correction electrode 12, the sensor 10 detects the capacitance Cz between the detection electrode 11 and the correction electrode 12 adjacent to the detection electrode 11 using the detection circuit 15. The reference potential GND is a reference potential in the sensor 10, such as a ground potential.

[0027] The correction electrode 12 is provided so as to extend in the detection direction Y in parallel with the detection electrode 11. The correction electrode 12 is formed so that at least a part of the correction electrode 12 is curved in the same direction as the curvature of the detection electrode 11. Other features related to the shape of the correction electrode 12 are similar to those of the detection electrode 11, and therefore will not be described here.

[0028] The active shield electrode 13 is an electrode for suppressing the flow of displacement current between the detection electrode 11 and the position of the active shield electrode 13. The active shield electrode 13 is connected to the other end of the resistive element R1, and a signal S1 having the same potential as the detection signal S0 is supplied from the buffer circuit BUF1 via the resistive element R1.

[0029] The active shield electrode 13 is provided so as to extend in the detection direction Y in parallel with the detection electrode 11 and the correction electrode 12. The active shield electrode 13 is formed so that at least a portion of the electrode is curved in the same direction as the curvature of the detection electrode 11. The shape of the active shield electrode 13 is the same as that of the detection electrode 11, and therefore a description thereof will be omitted.

[0030] Next, the arrangement of the detection electrodes 11, correction electrodes 12, and active shield electrodes 13 will be described. First, the detection electrodes 11 are provided on the right side of the correction electrodes 12 in the detection direction Y (in this example, on the side of direction X). Furthermore, the active shield electrodes 13 are provided on the right side of the detection electrodes 11 in the detection direction Y. As described above, a predetermined number of electrodes are provided along the detection surface S in the order of the correction electrodes 12, detection electrodes 11, and active shield electrodes 13 from the left side (in this example, the side opposite direction X). Note that the positions of the correction electrodes 12 and active shield electrodes 13 relative to the detection electrodes 11 may be reversed.

[0031] The detection electrodes 11 and the correction electrodes 12 are also arranged so that at least some of their positions in the detection direction Y are equally spaced from each other. Specifically, the detection electrodes 11 and the correction electrodes 12 are arranged so that the distance between positions P near the center in the detection direction Y is distance d. Similar to the distance between the detection electrodes 11 and the correction electrode 12, the distance between the detection electrodes 11 and the active shield electrode 13 is also arranged so that the distance between the positions P is distance d. Similar to the distance between the detection electrodes 11 and the correction electrode 12, the distance between the active shield electrode 13 and the correction electrode 12 is also arranged so that the distance between the positions P is distance d.

[0032] The signal generating circuit 14 is, for example, an AC signal source or an arbitrary waveform generator. The signal generating circuit 14 generates a detection signal S0 and transmits the detection signal S0 from its output terminal to the non-inverting input terminal + of the amplifier circuit AMP and the detection electrode 11 via a resistor element R0. The signal generating circuit 14 also transmits the detection signal S0 from its output terminal to the input terminals of the buffer circuits BUF1 and BUF2. The signal generating circuit 14 also has a reference terminal to which a reference potential GND is supplied.

[0033] The resistance elements R0 to R2 are, for example, resistors and have approximately the same resistance value. The resistance element R0 divides the potential of the detection signal S0 transmitted from the signal generating circuit 14 using the capacitance Cx of the detection space AREA and the resistance element R0. The divided potential is input to the non-inverting input terminal + of the amplifier circuit AMP and the detection electrode 11. One end of the resistance element R0 is connected to the input terminals of the buffer circuits BUF1 and BUF2 and the output terminal of the signal generating circuit 14, and the other end is connected to the non-inverting input terminal + of the amplifier circuit AMP and the plurality of detection electrodes 11.

[0034] The resistive element R1 divides the potential of the signal S1 transmitted from the signal generating circuit 14 via the buffer circuit BUF1 using the active shield electrode 13, the capacitance Cx of the detection space AREA, and the resistive element R1. The divided potential is input to the active shield electrode 13. One end of the resistive element R1 is connected to the output terminal of the buffer circuit BUF1, and the other end is connected to the active shield electrode 13.

[0035] The resistive element R2 and the capacitive element C0 divide the potential of the signal S2 transmitted from the signal generating circuit 14 via the buffer circuit BUF2. The divided potential is input to the inverting input terminal − of the amplifier circuit AMP. One end of the resistive element R2 is connected to the output terminal of the buffer circuit BUF2, and the other end is connected to the inverting input terminal − of the amplifier circuit AMP and the other end of the capacitive element C0.

[0036] The capacitance element C0 is, for example, a capacitor. The capacitance element C0 divides the potential of the signal S2 using the resistance element R2 and the capacitance element C0. The reference potential GND is supplied to one end of the capacitance element C0, and the other end is connected to the other end of the resistance element R2 and the inverting input terminal of the amplifier circuit AMP.

[0037] The short-circuit control element SW is, for example, a switching element or a transistor. The short-circuit control element SW switches the conduction state between both ends to either a conductive state or a non-conductive state in accordance with a control command from the control circuit 16. The short-circuit control element SW has one end supplied with a reference potential GND, the other end connected to the correction electrode 12, and a control terminal connected to the control circuit 16.

[0038] The buffer circuits BUF1 and BUF2 are, for example, voltage followers that electrically isolate the circuit on the input terminal side from the circuit on the output terminal side and output a signal at the same potential as the signal input to the input terminal from the output terminal. The buffer circuit BUF1 converts the detection signal S0 input from the signal generation circuit 14 into a signal S1 at the same potential as the detection signal S0 and outputs the signal S1 via a resistor element R1 toward the active shield electrode 13. The input terminal of the buffer circuit BUF1 is connected to the output terminal of the signal generation circuit 14, one end of the resistor element R0, and the input terminal of the buffer circuit BUF2, and the output terminal is connected to one end of the resistor element R1.

[0039] The buffer circuit BUF2 converts the detection signal S0 input to its input terminal from the signal generating circuit 14 into a signal S2 having the same potential as the detection signal S0, and outputs the signal S2 to the inverting input terminal - of the amplifier circuit AMP via a resistor element R2. The buffer circuit BUF2 has an input terminal connected to the output terminal of the signal generating circuit 14, one end of the resistor element R0, and the input terminal of the buffer circuit BUF1, and an output terminal connected to one end of the resistor element R2.

[0040] The detection circuit 15 detects a change in the capacitance Cx in the detection space AREA based on the potential of the detection electrode 11 and the potential at one end of the capacitance element C0. The detection circuit 15 also detects the presence or absence of an object 2 to be detected in the detection space AREA based on the detected change in the capacitance Cx. The main part of the detection circuit 15 includes, for example, an amplifier circuit AMP, a signal extraction circuit 151, and a conversion circuit 152.

[0041] The amplifier circuit AMP is a differential amplifier circuit such as an instrumentation amplifier or an operational amplifier. The amplifier circuit AMP amplifies the potential difference between the non-inverting input terminal + and the inverting input terminal by a first magnification factor and outputs a signal having the amplified potential from an output terminal. The first magnification factor is, for example, 1, 2, or 10, and is either a unique value that is set in advance or a variably set value. The amplifier circuit AMP has a non-inverting input terminal + connected to the other end of the resistor element R0 and the detection electrode 11, an inverting input terminal − connected to the other end of the resistor element R2 and the other end of the capacitor element C0, and an output terminal connected to the signal extraction circuit 151.

[0042] The signal extraction circuit 151 is, for example, a lock-in amplifier. The signal extraction circuit 151 extracts components in the frequency band of the detection signal S0 from the signal output from the amplifier circuit AMP. The signal extraction circuit 151 amplifies the signal having the extracted components by a second magnification factor, and outputs the amplified signal to the conversion circuit 152. The second magnification factor is, for example, 20 times, 100 times, 1000 times, or the like, and is set to a unique value in advance or is set to a variably value.

[0043] The conversion circuit 152 is, for example, an AD (analog-to-digital) converter. The conversion circuit 152 performs AD conversion on the signal output from the signal extraction circuit 151 and outputs the converted signal to the control circuit 16.

[0044] The control circuit 16 controls the operation of the sensor 10 in accordance with a control command transmitted from outside the sensor 10. The control circuit 16 also outputs, to the outside of the sensor 10, information relating to whether or not an object 2 has been detected in the detection space AREA.

[0045] The control circuit 16 has two operating modes, a correction mode and a detection mode, and operates by switching between the correction mode and the detection mode after setting the operating mode to the detection mode. When the operating mode is the detection mode, the control circuit 16 detects the capacitance Cx between the detection electrode 11 and the detection space AREA. On the other hand, when the operating mode is the correction mode, the control circuit 16 detects the capacitance Cz between the detection electrode 11 and the correction electrode 12. When the operating mode is set to the correction mode, the control circuit 16 supplies a reference potential GND to the correction electrode 12. When the operating mode is set to the detection mode, the control circuit 16 stops the supply of the reference potential GND to the correction electrode 12. When supplying the reference potential GND to the correction electrode 12, the control circuit 16 controls the short-circuit control element SW to make both ends conductive. On the other hand, when stopping the supply of the reference potential GND to the correction electrode 12, the control circuit 16 controls the short-circuit control element SW to open both ends.

[0046] The control circuit 16 determines whether the difference between the capacitance Cx detected in the detection mode and the capacitance Cz detected in the correction mode is within a predetermined range. If the determination is affirmative, the control circuit 16 determines that the object 2 has not been detected in the detection space AREA. On the other hand, if the determination is negative, the control circuit 16 determines that the object 2 has been detected in the detection space AREA.

[0047] The flow of operation of the control circuit 16 will be described with reference to FIGS. 2 and 3. FIG. 3 is a diagram showing the operation of the sensor 10 shown in FIG. 1 when the operation mode of the sensor 10 is the correction mode. In FIG. 3, the capacitance between the detection electrode 11 and the correction electrode 12 is assumed to be capacitance Cz. When detecting an object 2 in the detection space AREA, the control circuit 16 first sets the operation mode to the correction mode and detects capacitance Cz. Next, the control circuit 16 sets the operation mode to the detection mode and detects capacitance Cx, and continues to determine whether or not an object 2 has been detected in the detection space AREA. Furthermore, the control circuit 16 periodically switches the operation mode to the correction mode, detects capacitance Cz, updates the measured value of capacitance Cz, and then switches the operation mode back to the detection mode.

[0048] <Effects> As described above, in this embodiment, the sensor 10 is provided with the detection electrodes 11 and correction electrodes 12 extending in the detection direction Y perpendicular to the detection surface S and arranged in parallel. This improves the detection accuracy per area of ​​the detection electrodes 11 and correction electrodes 12 in the sensor 10. Therefore, the sensor 10 can detect the object 2 with high accuracy. Furthermore, the sensor 10 can detect the object 2 in a space-saving manner.

[0049] In this embodiment, the detection electrode 11 and the correction electrode 12 are formed so that at least a part of the detection electrode 11 and the correction electrode 12 is curved or bent in a direction X perpendicular to the detection direction Y. Therefore, when the object 2 collides with the sensor 10, the detection electrode 11 and the correction electrode 12 bend in the curved or bent direction to absorb the impact, thereby reducing damage to the object 2.

[0050] In this embodiment, the sensor 10 further includes an active shield electrode 13 that is provided in parallel with the detection electrode 11 and the correction electrode 12 and extends along the detection direction Y, and that receives a signal having the same potential as the detection signal S0. Therefore, the sensor 10 can detect the object 2 with higher accuracy because the displacement current flowing between the detection electrode 11 and the active shield electrode 13 is suppressed.

[0051] In this embodiment, the detection electrodes 11 and the correction electrodes 12 are provided in plurality so that at least some of the positions in the detection direction Y are equally spaced between adjacent electrodes. Therefore, the sensor 10 can detect the capacitance Cz between the detection electrodes 11 and the correction electrodes 12 with higher accuracy.

[0052] In this embodiment, the sensor 10 also includes a control circuit 16 that controls the operation of the detection circuit 15 to detect the capacitance Cz between the detection electrode 11 and the correction electrode 12 when the operation mode is the correction mode, and to detect the object 2 when the operation mode is the detection mode. Therefore, the sensor 10 can detect the object 2 with higher accuracy.

[0053] In this embodiment, the robot 1 includes a sensor 10, a movable arm 20 on which the sensor 10 is mounted, and a wrist 40 connected to the arm 20 to perform work on a workpiece. Therefore, the robot 1 can detect the object 2 with high accuracy using the sensor 10.

[0054] <Modification> The present invention is not limited to the above-described embodiments. In other words, variations of the above-described embodiments, which are appropriately modified by a person skilled in the art, are also included within the scope of the present invention as long as they include the features of the present invention. Furthermore, the elements of the above-described embodiments and the modifications described below can be combined to the extent technically possible, and such combinations are also included within the scope of the present invention as long as they include the features of the present invention.

[0055] For example, in this embodiment, the detection electrode 11, the correction electrode 12, and the active shield electrode 13 are formed in a crescent shape, but this is not limiting. The detection electrode 11, the correction electrode 12, and the active shield electrode 13 may have any shape as long as they can absorb a force applied in the detection direction Y by deformation of the electrodes, or can disperse the force in another direction such as the direction X horizontal to the detection surface S, or can be resilient. Here, other examples of the shapes of the detection electrode 11, the correction electrode 12, and the active shield electrode 13 will be described with reference to FIGS. 4A to 4C .

[0056] 4A is a diagram showing a second example of the electrodes of the sensor 10 shown in FIG. 2. As shown in FIG. 4A, the detection electrode 11, correction electrode 12, and active shield electrode 13 in FIG. 4A are formed by bending plate- or rod-shaped members in direction X from position P. With this configuration, the sensor 10 can be easily manufactured because the electrodes are formed by bending plate- or rod-shaped members or by connecting two members so that they form a predetermined angle. Therefore, the sensor 10 can detect the object 2 at low cost.

[0057] 4A, the electrodes are formed so as to bend in direction X, but they may also be formed in a triangular wave shape that has a bend in direction X as well as a bend in direction opposite to direction X. With this configuration, the electrodes of sensor 10 can be easily manufactured, allowing sensor 10 to detect object 2 at low cost. Furthermore, because the electrodes are formed in a triangular wave shape, sensor 10 has elasticity in detection direction Y, and can therefore better absorb and reduce impact when an object such as object 2 collides with sensor 10.

[0058] 4B is a diagram showing a third example of the electrodes of the sensor 10 shown in FIG. 2. As shown in FIG. 4B, the detection electrode 11, correction electrode 12, and active shield electrode 13 in FIG. 4B are formed in a rectangular wave shape along the detection direction Y. With this configuration, the sensor 10 can be easily manufactured because the electrodes are formed by bending plate- or rod-shaped members or by connecting two members or two members so that they form a predetermined angle, and can detect the object 2 at low cost. Furthermore, because the electrodes of the sensor 10 are formed in a rectangular wave shape, the sensor 10 has elasticity in the detection direction Y, and can therefore better absorb and reduce impact when an object such as the object 2 hits the sensor 10.

[0059] Fig. 4C is a diagram showing a fourth example of the electrodes of the sensor 10 shown in Fig. 2. As shown in Fig. 4C, the detection electrode 11, the correction electrode 12, and the active shield electrode 13 in Fig. 4C are formed in a spring shape with the detection direction Y as the central axis. With this configuration, the sensor 10 has elasticity in the detection direction Y according to the elastic coefficient of the spring because the electrodes are formed in a spring shape, and therefore can better absorb and reduce the impact when an object such as the detection object 2 collides with the sensor 10.

[0060] 2 and 4A to 4C, the sensor 10 has two detection electrodes 11, two correction electrodes 12, and one active shield electrode 13, but the present invention is not limited to this. The sensor 10 may have a predetermined number of detection electrodes 11, correction electrodes 12, and active shield electrodes 13. With this configuration, the sensor 10 can detect the presence or absence of an object 2 in a detection space AREA having a size corresponding to the number of electrodes with accuracy corresponding to the number of electrodes.

[0061] In this embodiment, the sensor 10 is a capacitance-type proximity sensor, and various components such as the signal generating circuit 14, the detection circuit 15, and the control circuit 17 are configured to operate a capacitance-type proximity sensor, but this is not limited to this. The sensor 10 may be any type of sensor that detects the object 2 using electrodes. With this configuration, the sensor 10 can detect the object 2 with high accuracy, regardless of the type of sensor.

[0062] Furthermore, in this embodiment, the sensor 10 is provided on the robot 1, but this is not limiting. The sensor 10 may be provided on a moving part of any machine (for example, industrial machine) as long as the machine has a moving part exposed to the outside. With this configuration, the industrial machine can detect the object 2 around the industrial machine with high accuracy using the sensor 10. [Explanation of symbols]

[0063] 1... robot, 10... sensor, 11... detection electrode, 12... auxiliary electrode, 13... active shield electrode, 14... signal generation circuit, 15... detection circuit, 16... control circuit

Claims

1. a detection electrode provided to extend along a detection direction perpendicular to a detection surface for detecting an object; a correction electrode provided in parallel with the detection electrode and extending along the detection direction; a signal generating circuit that generates a detection signal and transmits the generated detection signal to the detection electrode; a detection circuit that detects the object to be detected according to the potential of the detection electrode; A sensor comprising:

2. the detection electrode is formed so that at least a part of the detection electrode is curved or bent in a direction perpendicular to the detection direction, the correction electrode is formed so that at least a part of the correction electrode is curved or bent in the same direction as the curved or bent direction of the detection electrode; 2. The sensor of claim 1.

3. an active shield electrode that is provided in parallel with the detection electrode and the correction electrode so as to extend along the detection direction, and that is supplied with a signal having the same potential as the detection signal; the detection electrode is provided on the right side of the correction electrode along the detection direction, the active shield electrode is provided on the right side of the detection electrode along the detection direction.

2. The sensor of claim 1.

4. the detection electrodes and the correction electrodes are provided in plurality so that adjacent electrodes are equally spaced apart at least in part in the detection direction; The sensor according to any one of claims 1 to 3.

5. a control circuit having two operation modes, a correction mode and a detection mode, which controls the operation of the detection circuit so that the capacitance between the detection electrode and the correction electrode is detected when the operation mode is the correction mode, and the object is detected when the operation mode is the detection mode; The sensor of claim 1 further comprising:

6. a sensor including a detection electrode extending along a detection direction perpendicular to a detection surface for detecting an object to be detected, a correction electrode extending along the detection direction in parallel with the detection electrode, a signal generating circuit that generates a detection signal and transmits the generated detection signal to the detection electrode, and a detection circuit that detects the object to be detected in accordance with the potential of the detection electrode; a movable arm portion on which the sensor is provided; a wrist portion connected to the arm portion and performing work on a workpiece; A robot equipped with:

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