Monitoring module, x-ray diffraction device, and monitoring system

Abstract

Provided are a monitoring module and a monitoring system capable of ensuring driving at a fixed speed and maintaining traceability of each measurement. A monitoring module for monitoring the operation of a stepping motor used in an X-ray diffraction device is provided with: a detection unit (164) for detecting a specific rotational position of the stepping motor and generating a detection signal; a measurement unit (165) that measures the time interval of the detection signal; a determination unit (166) that determines whether or not a measured value corresponding to a time interval of the detection signal matches a reference value corresponding to a rotation time between specific rotation positions determined on the basis of an operation instruction to the stepping motor; and an information transmission unit (167) that transmits operation abnormality information to the outside if the measured value does not match the reference value.

Description

Technical Field

[0001] The present invention relates to a monitoring module, an X-ray diffraction device and a monitoring system for monitoring the action of a stepping motor. Background Art

[0002] In an X-ray diffraction device, various drive mechanisms using stepping motors are provided to move the goniometer or the sample. Basically, malfunctions are prevented by using a stepping motor with sufficient margin for the torque required for driving and by regularly maintaining the drive mechanism, but it is also important to monitor the operation of the stepping motor. A stepping motor with an encoder detects abnormal operation of the stepping motor based on the difference between the command pulse to the stepping motor and the current position of the encoder.

[0003] However, when using a stepper motor with an encoder, (1) the motor is expensive, and (2) the motor is large and prone to mechanical interference. If the stepper motor is not monitored, it may sometimes lose step due to deterioration of the grease of the drive mechanism, but the abnormality cannot be detected. In this case, the loss of step is mostly inferred based on the abnormality of the measured profile. In this case, it is difficult to determine when the abnormality occurred and it is difficult to maintain the traceability of each measured profile.

[0004] In this regard, a technology for detecting stepping out of step of a stepping motor using an origin sensor is known (see Patent Document 1). The device described in Patent Document 1 counts the command pulses during the rotation of the motor, and if the value of the counter exceeds the number of pulses for one rotation of the motor before the output of the origin position sensor is output, it is determined that a stepping out has occurred, thereby detecting the stepping out of step of the motor without an encoder.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 9-93993

[0008] However, although the device described in Patent Document 1 can detect a step-out, it cannot detect an abnormality when no pulse is output due to a fault in the pulse motor controller or when a sensor output is output despite less than one rotation due to a fault in the origin sensor. Summary of the invention

[0009] The present invention has been made in view of such circumstances, and an object of the present invention is to provide a monitoring module and a monitoring system that can ensure that a stepping motor is driven at a constant speed and can maintain the traceability of each measurement.

[0010] (1) In order to achieve the above-mentioned purpose, the monitoring module of the present invention is a monitoring module for monitoring the operation of a stepping motor used in an X-ray diffraction device, and is characterized in that it comprises: a detection unit, which detects a specific rotational position of the stepping motor and generates a detection signal; a measuring unit, which measures the time interval of the detection signal; a determination unit, which determines whether a measured value equivalent to the time interval of the detection signal is consistent with a reference value, wherein the reference value is equivalent to the rotation time between the specific rotational positions determined based on an operation instruction to the stepping motor; and an information transmission unit, which transmits abnormal operation information to the outside when the measured value is inconsistent with the reference value.

[0011] (2) In addition, in the monitoring module described in (1) above, the detection unit is a rotation sensor that detects the detection signal every time the stepping motor rotates one circle.

[0012] (3) In addition, in the monitoring module described in (1) or (2) above, the determination unit determines whether the measured value is consistent with the reference value by determining whether the difference between the measured value and the reference value is within a specified range.

[0013] (4) In addition, in the monitoring module described in any one of (1) to (3) above, the stepping motor is used for a setting position adjustment mechanism of a goniometer, a sample stage, a variable slit, or a detector.

[0014] (5) In addition, the monitoring module described in any one of (1) to (4) above is characterized by further comprising a monitoring condition setting unit for setting the number of detection signals included in the time interval of the detection signals.

[0015] (6) In addition, the X-ray diffraction device of the present invention is an X-ray diffraction device in which the operation of the stepping motor is monitored, and is characterized in that it comprises: a goniometer that controls the positions of an X-ray source, a sample, and a detector; an adjustment mechanism that adjusts the configuration of a sample table supporting the sample; and the monitoring module described in (1) to (5) above, wherein the stepping motor drives at least one of the goniometer and the adjustment mechanism.

[0016] (7) In addition, the monitoring system of the present invention is a monitoring system for monitoring the operation of a stepping motor, and is characterized in that it comprises: the X-ray diffraction device described in (6) above; and a processing device that controls the monitoring module, and the processing device displays operation assurance or operation abnormality based on the presence or absence of the transmitted operation abnormality information.

[0017] (8) In addition, in the monitoring system described in (7) above, the operation guarantee is numerical information indicating reliability of a relationship between the rotation speed of the stepping motor and the reference value. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram showing the configuration of the monitoring system of the present invention.

[0019] Figure 2 It is a block diagram showing the functional structure of the monitoring module of the present invention.

[0020] Figure 3 This is a schematic diagram showing an example of the configuration of the monitoring module of the present invention.

[0021] Figure 4 is a timing diagram showing a pulse signal and a detection signal.

[0022] Description of Reference Numerals

[0023] 10. Surveillance System

[0024] 100 X-ray diffraction device

[0025] 110 X-ray source

[0026] 115 Variable Slit

[0027] 120 Detector

[0028] 130 Goniometer

[0029] 140 Sample table

[0030] 145 Adjustment mechanism

[0031] 160 Monitoring module

[0032] 161 Monitoring condition setting unit

[0033] 162 Action Instruction Unit

[0034] 163 Pulse signal output unit

[0035] 164 Testing Department

[0036] 165 Measurement Department

[0037] 166 Judgment Department

[0038] 167 Information Transmission Department

[0039] 200 Processing device

[0040] D1 Motor Driver Base Board

[0041] M1 Stepper Motor

[0042] S0 specimen

[0043] S1 Rotation sensor. DETAILED DESCRIPTION

[0044] Next, embodiments of the present invention will be described with reference to the accompanying drawings. In order to facilitate understanding of the description, the same components are denoted by the same reference numerals in the drawings, and repeated descriptions are omitted.

[0045] [principle]

[0046] In the previous position-based action monitoring, it is confirmed whether the number of pulse signals between the detection signals of the rotation sensor is normal. In this case, even if the rotation speed is abnormal, if the position is normal, it will be judged as normal. However, the measurement using the X-ray diffraction device 100 has a unique situation in which the reliability is guaranteed by driving the goniometer 130 or the sample stage 140 at a fixed speed. Therefore, in this field, if the technology of monitoring the time for the rotating shaft of the stepping motor to rotate a fixed angle can be applied to daily monitoring, it will be highly useful. The present invention is based on such a situation and is not based on position monitoring but on time monitoring, which is a concept that has never been seen before.

[0047] [Surveillance system]

[0048] Figure 1 1 is a schematic diagram showing the structure of the monitoring system 10. The monitoring system 10 includes an X-ray diffraction device 100 and a processing device 200. The X-ray diffraction device 100 irradiates the sample S0 with X-rays and detects the scattered X-rays so that the X-ray diffraction measurement can be performed. The X-ray diffraction device 100 drives each mechanism inside by a stepping motor M1, and the monitoring module 160 monitors the stepping motor M1 rotating the rotating shaft at a fixed rotation speed.

[0049] [Processing device]

[0050] The processing device 200 controls the operation of the X-ray diffraction device 100 and displays the information transmitted from the monitoring module 160. For example, the operation guarantee or the operation abnormality is displayed based on the presence or absence of the transmitted operation abnormality information. The processing device 200 is composed of a computer in which a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and a memory are connected to a bus. The processing device 200 can be a PC terminal or a server on the cloud. In addition, not only the entire device can be set on the cloud, but also a part of the device or a part of the function within the device can be set on the cloud.

[0051] [X-ray diffraction device]

[0052] The X-ray diffraction apparatus 100 includes an X-ray source 110 , a variable slit 115 , a detector 120 , a goniometer 130 , a sample stage 140 , an adjustment mechanism 145 , a stepping motor M1 , and a monitoring module 160 . Figure 1 The example shown is simplified, but in reality the X-ray diffraction apparatus 100 may also include a mechanism for rotating and swinging the sample, a mechanism for adjusting the installation position of the detector, and other driving mechanisms.

[0053] The X-ray source 110 generates X-rays and irradiates the X-rays toward the sample. The variable slit 115 is a slit with a variable opening width. The detector 120 detects X-rays scattered by the sample S0. The goniometer 130 is controlled according to the measurement, and measures the positions of the X-ray source 110, the sample S0, and the detector 120. The goniometer 130 can be any type of horizontal rotation type, longitudinal type, or sample horizontal type. In addition to the θ axis, 2θ axis, tilt axis, and in-plane rotation axis, the scanning axis of the goniometer 130 can also have an in-plane (2θχ) axis. The sample stage 140 supports the sample S0. The adjustment mechanism 145 adjusts the configuration of the sample stage 140 supporting the sample S0. The configuration includes not only the position, but also the orientation or posture.

[0054] The stepper motor M1 transmits the rotational force of the rotating shaft to the variable slit 115, the goniometer 130, and the adjustment mechanism 145 to drive them. In addition, if there is a rotation or swing mechanism of the sample, they can also be driven. In addition, for convenience, the same reference numerals are used to show, but the stepper motor M1 that drives each mechanism is independently provided.

[0055] The monitoring module 160 monitors the operation of the stepper motor M1 used in the X-ray diffraction device 100. For example, the stepper motor M1 used in the goniometer 130, the sample stage 140 or the variable mechanism of the slit, and the detector setting position adjustment mechanism can be used as the monitoring object. In this way, it can be ensured that the rotation speed of the stepper motor M1 rotating the rotation axis is constant for the drive such as the scanning of the measurement by the goniometer arm, the rotation or swing of the sample stage 140, the adjustment of the opening width by the variable slit 115, and the adjustment of the camera length by the detector setting position adjustment mechanism.

[0056] [Monitoring module configuration]

[0057] Figure 2 1 is a block diagram showing the functional structure of the monitoring module 160. The monitoring module 160 includes a monitoring condition setting unit 161, an action instruction unit 162, a pulse signal output unit 163, a detection unit 164, a measuring unit 165, a determination unit 166, and an information transmission unit 167. Among them, the monitoring condition setting unit 161, the action instruction unit 162, the pulse signal output unit 163, the measuring unit 165, the determination unit 166, and the information transmission unit 167 are composed of an integrated circuit of a motor driver substrate D1 in a pulse motor controller (Pulse Motor Controller). The integrated circuit is preferably an FPGA (Field Programmable Gate Array). It can also be composed of a control device such as a PLC (Programmable Logic Controller) instead of a substrate.

[0058] The monitoring condition setting unit 161 sets monitoring conditions such as the time interval of the detection signal before the action. The time interval of the detection signal refers to the time interval of each specified number of detection signals. It can be once or twice. As a monitoring condition, for example, the number of revolutions of the motor can be set, and the time between the detection signals of each motor revolution can be monitored. In addition, a threshold value of the difference between the measured time interval of the detection signal and the reference value can also be set. By determining whether the difference is within the specified range based on the set threshold, it can be determined whether the action is abnormal. Since the appropriate range of the specified range changes according to the measurement, it is preferably set according to instructions from the processing device 200.

[0059] The operation instruction unit 162 calculates the number of pulse signals and the pulse signal speed required for the movement by the operation of the stepping motor M1 and outputs an operation start command. The pulse signal output unit 163 outputs a pulse signal to the driver of the stepping motor M1 according to the operation start command.

[0060] The detection unit 164 detects that the rotating shaft of the stepping motor M1 is at a specific rotational position and generates a detection signal. The specific rotational position refers to a position at each fixed angle, such as 60°, 120°, 180°, etc., or 360°, 720°, etc., every 360°.

[0061] The detection unit 164 is a rotation sensor that outputs a detection signal every time the rotating shaft of the stepping motor M1 rotates a fixed angle. It is particularly preferred to use a rotation sensor (so-called index sensor) that can detect one rotation. As a result, a low-cost monitoring system can be constructed compared to the case of using an encoder. In addition, since the size of the motor unit is reduced, the accessories can be miniaturized. In addition, when using a rotation sensor, it is a prerequisite to use a motor driver substrate equipped with a function of detecting abnormal operation of the motor.

[0062] The rotation sensor can be composed of, for example, a circular plate with a notch mounted on the rotating shaft of the stepper motor M1 and a photoelectric sensor that emits a signal at the notch position. By aligning the central axis of the circular plate with the central axis of the rotating shaft and forming a notch on the circular plate, a detection signal can be obtained from the rotation sensor once per rotation. In addition, a circular plate with a marker or a magnetic sensor can also be used to detect rotation.

[0063] The rotation sensor may be any sensor that outputs a detection signal every time the rotating shaft rotates a fixed angle, and need not necessarily be a rotation sensor that detects a signal once per rotation. It may also be a rotation sensor that detects a signal once per rotation of 1 / 2 rotation, or a rotation sensor that detects a signal once per rotation of 1 / 3 rotation.

[0064] The encoder can also be used as a kind of rotation sensor. The encoder sets the detected part at multiple locations of the circular plate, and outputs a detection signal when the detected part is detected by the sensor. Conventional rotation sensors are used to confirm the position. In the present invention, the rotation speed of the stepping motor M1 can be guaranteed by measuring the time interval of the detection signal.

[0065] The measuring unit 165 measures the time interval of the detection signal obtained from the detection unit 164. The determination unit 166 determines whether the measured value corresponding to the time interval of the detection signal is a reference value corresponding to the rotation time between specific rotation positions determined based on the action instruction to the stepping motor M1. In addition, the "measured value" includes not only the measured value, but also an equivalent numerical value calculated from the measured value. It is preferred to determine whether the measured value is consistent with the reference value based on whether the difference between the measured value and the reference value is within a specified range. Thus, when the time for the rotating shaft of the stepping motor M1 to advance between specific rotation positions is not fixed, it can be judged as abnormal. In addition, the reference value and the measured value can also be the time itself for the rotating shaft to rotate between specific rotation positions, or can be a numerical value such as the rotation speed equivalent thereto or the time per rotation.

[0066] When the measured value is not the reference value, the information transmission unit 167 transmits the abnormal operation information to the outside. Thus, it is possible to ensure that the components of the X-ray diffraction device 100 are driven at a fixed speed and to maintain the traceability of each measurement distribution diagram. In addition, the abnormal operation information can also be transmitted by not sending and receiving regular normal information.

[0067] [Configuration example]

[0068] Figure 3 1 is a schematic diagram showing an example of the configuration of the monitoring module 160. Figure 3 In the configuration example shown, first, the main controller (1) calculates the number of pulse signals and pulse signal speed required for driving each mechanism and moving by the measuring action based on the instruction from the host PC (processing device), and sets the monitoring conditions such as the reaction time of the rotation sensor S1 during the constant speed action (excluding the acceleration and deceleration time) to the FPGA (5) before the action. By this setting, for example, the time between the detection signals of each rotation of the motor 100 can also be measured. In addition, for example, when measuring 20 deg / min, it can be guaranteed that the action is performed within the speed range of 20 deg / min±0.05%.

[0069] The main controller (1) sets the pulse signal number, pulse signal speed setting, and action start command to the PMC (2). Then, the PMC (2) outputs the pulse signal to the stepper motor driver (3). In addition, PMC is the abbreviation of Pulse Motor Controller. In addition, it can also be considered that the main controller and FPGA are integrated in structure.

[0070] The FPGA (5) of the motor driver substrate D1 counts the input pulse signal and measures the time interval of the detection signal. Every time the stepper motor M1 rotates one circle (depending on the resolution, for example, 500 pulses), a detection signal is output from the rotation sensor. The measurement result of the time interval of the detection signal is sent to the main controller (1).

[0071] According to this configuration, when an abnormality exists in the PMC peripheral circuit and a pulse signal is not output, even though the operation has started, the abnormality that the pulse signal is not output can be detected. When a pulse signal is output but no detection signal is detected even if the motor rotates one circle or more, it is possible to identify that the motor has lost step or a rotation sensor (no output) has failed, and the abnormality can be detected.

[0072] Every time the stepper motor M1 rotates one circle, a detection signal from the rotation sensor is output. During the constant speed operation of the stepper motor M1 (excluding the acceleration and deceleration time), the time interval for the rotation sensor to respond is fixed.

[0073] In the past, for example, when measuring at a speed of 20 deg / min (or 20 mm / min), it was not known whether the drive mechanism was actually operating at that speed, so the reliability of the measurement could not be guaranteed. By using FPGA (5) to measure the interval of the detection signal, the deviation of the motor operation speed during the measurement process can be measured. In this way, the operation of the stepper motor M1 during the measurement can be guaranteed. The operation of the drive mechanism at each angle or position within the measurement range can also be guaranteed.

[0074] For example, when the diffraction angle range of 10 to 15 degrees is measured at 20 degrees / min, the following numerical range indicating reliability can be grasped.

[0075] 10~11 degrees 20deg / min±0.03% 11~12 degrees 20deg / min±0.02% 12~13 degrees 20deg / min±0.01% 13~14 degrees 20deg / min±0.03% 14~15 degrees 20deg / min±0.02%

[0076] The stepper motor M1 is used not only to drive the goniometer during the measurement process, but also to drive various drive mechanisms such as the slit adjustment axis of the incident and light receiving optical systems, the rotation and swing axis of the sample stage. In the measurement of X-ray diffraction, sometimes the slit width on the incident side is automatically changed while changing the diffraction angle so that the irradiation width on the sample surface becomes fixed, or the sample is rotated or swung at a fixed speed to reduce the influence of orientation or coarse particles. With the above-mentioned structure, the operation of the stepper motor can be guaranteed for the drive mechanism of each axis during the measurement process. In addition, since the motor speed during movement is controlled by the main controller (1), the operation can be guaranteed not only during measurement, but also during movement performed by the drive mechanism alone. For example, when the axis moves before the measurement starts, since it is monitored whether the motor moves at the speed when the axis moves, it can be guaranteed that the slit width of the variable slit, the XY coordinate position of the sample stage, and the camera length of the detector are accurately moved to the position as the set value.

[0077] [Monitoring module actions]

[0078] An operation example of the monitoring module 160 configured as described above will be described. Figure 4 2 is a timing chart showing a pulse signal and a detection signal. The pulse signal is a signal for operating the stepping motor M1 , and the detection signal is represented by “INDEX” and shows a signal detected by the detection unit 164 .

[0079] When performing measurement using the X-ray diffraction device 100, when the control device instructs the stepping motor M1, the monitoring conditions are set according to the instruction and the action instruction is performed. Then, the pulse signal output unit 163 outputs a pulse signal at a fixed interval in a manner that is driven at a rotation speed according to the action instruction. The stepping motor M1 rotates the rotation axis by the pulse signal.

[0080] On the other hand, the detection unit 164 outputs a detection signal every time the stepping motor M1 rotates by a fixed angle. The measurement unit 165 measures the time interval between a predetermined number of detection signals as a measured value of the time taken for the stepping motor M1 to rotate by the fixed angle.

[0081] The determination unit 166 determines whether the measured value is consistent with the reference value when the rotation time between specific rotation positions determined based on the action instruction is used as a reference value. For example, if the number of pulse signals of each detection signal is verified, it is possible to confirm whether the stepping motor M1 is out of step, but it is impossible to confirm that the rotation speed is fixed. However, by comparing the time spent between specific rotation positions calculated in accordance with the action instruction with the time interval of the detection signal measured by the sensor, the rotation speed can be guaranteed. When the calculated rotation speed is inconsistent with the reference value, the information transmission unit 167 transmits the abnormal action information to the processing device 200. The processing device 200 can immediately detect that the device is abnormal by notifying the occurrence of abnormal motor action on the application. In this way, the action of the stepping motor M1 can be monitored.

[0082] [Reliability display]

[0083] The action guarantee displayed by the processing device 200 is preferably numerical information indicating the reliability of the relationship between the stepping motor rotation speed and the reference value. The numerical value indicating the reliability is, for example, the numerical range of ±x% of the detected stepping motor rotation speed relative to the reference value. Thus, the user can confirm the reliability of the objective measurement on the spot when using the X-ray diffraction device.

Claims

1. A monitoring module for monitoring the operation of a stepping motor used in an X-ray diffraction device, characterized in that: have: A detection unit that detects a specific rotation position of the stepping motor and generates a detection signal; a measuring unit for measuring a time interval of the detection signal; a determination unit that determines whether a measured value corresponding to the time interval of the detection signal is consistent with a reference value, the reference value corresponding to the rotation time between the specific rotation positions determined based on an operation instruction to the stepping motor; as well as The information transmitting unit transmits abnormal operation information to the outside when the measured value does not coincide with the reference value.

2. The monitoring module according to claim 1, characterized in that: The detection unit is a rotation sensor that detects the detection signal every time the stepping motor rotates one turn.

3. The monitoring module according to claim 1 or claim 2, characterized in that: The determination unit determines whether the measured value matches the reference value by determining whether a difference between the measured value and the reference value is within a predetermined range.

4. The monitoring module according to claim 1 or claim 2, characterized in that: The stepping motor is used for a setting position adjustment mechanism of a goniometer, a sample stage, a variable slit, or a detector.

5. The monitoring module according to claim 1 or claim 2, characterized in that: The device further includes a monitoring condition setting unit for setting the number of detection signals included in the time interval of the detection signals.

6. An X-ray diffraction device, wherein the operation of the stepping motor is monitored, characterized in that: have: a goniometer, which controls the position of the X-ray source, sample, and detector; an adjustment mechanism that adjusts the configuration of a sample stage that supports the sample; and The monitoring module according to claim 1 or claim 2, The stepper motor drives at least one of the goniometer or the adjustment mechanism.

7. A monitoring system for monitoring the operation of the stepping motor, characterized in that: have: The X-ray diffraction apparatus according to claim 6; and a processing device, which controls the monitoring module, The processing device displays operation assurance or operation abnormality based on the presence or absence of the transmitted operation abnormality information.

8. The monitoring system according to claim 7, characterized in that The operation guarantee is numerical information indicating the reliability of the relationship between the rotation speed of the stepping motor and the reference value.

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