Measurement device

Abstract

This measurement device is provided with: a coordinate value calculation unit that calculates, on the basis of a signal input from a measurement instrument, a coordinate value of a position at which the shape of a measurement surface of a measurement object changes; a measurement information recording unit that records measurement information relating to a time interval at which the shape of the measurement surface of the measurement target changes; and a speed abnormality determination unit that determines that the relative speed between the measurement surface of the measurement object and the measurement instrument is abnormal when the time interval during which the shape of the measurement surface of the measurement object recorded by the measurement information recording unit changes is shorter than a predetermined first threshold value, and that determines that the relative speed between the measurement surface of the measurement object and the measurement instrument is abnormal when it is determined that the relative speed is abnormal. The present invention notifies that a measurement surface of a measurement object cannot be accurately evaluated.

Description

Technical Field

[0001] The present disclosure relates to an assay device. Background Art

[0002] There is a technology that analyzes the signal input from the measuring device and calculates the coordinate values ​​of the signal when it rises and falls, thereby performing shape evaluation (for example, Patent Document 1). Such a technology is used to detect the rise and fall of the gear teeth when processing a workpiece with a concave and convex shape on the surface, such as a gear, to perform gear tooth shape evaluation.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-055072 Summary of the invention

[0006] Problems to be solved by the invention

[0007] When measuring the shape of the object to be measured, the cycle time of the shape evaluation of the measured surface of the object to be measured can be shortened by increasing the relative speed between the measured surface of the object to be measured and the measuring device. For example, when evaluating the shape of the teeth of a gear, the cycle time of the shape evaluation of the gear can be shortened by increasing the rotation speed of the gear when the concavity and convexity of the teeth are measured by the measuring device. However, it takes a predetermined processing time for the measuring device to analyze the signal from the measuring device to calculate the coordinate values ​​of the rising position and the falling position of the tooth. Therefore, when the rise and fall are continuous within the processing time of the coordinate value calculation, each coordinate value may not be accurately calculated.

[0008] Therefore, it is desirable to be able to determine whether the relative speed between the measurement surface of the measurement target and the measurement device is controlled according to the processing capability of the measurement device.

[0009] Means for solving problems

[0010] The measuring device disclosed in the present invention determines whether the relative speed between the measuring surface of the measuring object and the measuring device is appropriate based on the processing capacity of the measuring device and the measuring information. The above-mentioned problem is solved by monitoring the input of the signal from the measuring device and determining whether the coordinate value of the position where the shape change of the workpiece occurs can be accurately calculated at the current speed.

[0011] Furthermore, one embodiment of the present disclosure is a measuring device comprising: a coordinate value calculation unit, which calculates the coordinate value of a position where the shape of a measuring surface has changed based on a signal input from a measuring instrument, and the measuring instrument moves the relative position of the measuring surface to the measuring object to measure the change in the shape of the measuring surface; a measurement information recording unit, which records measurement information related to the time interval for the shape change of the measuring surface of the measuring object; and a speed abnormality determination unit, which determines that the relative speed between the measuring surface of the measuring object and the measuring instrument is abnormal when the time interval for the shape change of the measuring surface of the measuring object recorded in the measurement information recording unit is shorter than a predetermined first threshold value, and when the speed abnormality determination unit determines that the relative speed between the measuring surface of the measuring object and the measuring instrument is abnormal, it notifies that the measuring surface of the measuring object cannot be accurately evaluated. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic hardware configuration diagram of the measuring device according to the first embodiment of the present disclosure.

[0013] Figure 2 This is a schematic diagram of gear shape measurement using the measuring device of this embodiment.

[0014] Figure 3 This is a block diagram showing the schematic functions of the measurement device according to the first embodiment of the present disclosure.

[0015] Figure 4 This is a graph showing an example of a sequence of distance data calculated based on a signal input from a measuring device.

[0016] Figure 5 This is a graph showing another example of a sequence of distance data calculated based on a signal input from a measuring device.

[0017] Figure 6 This is a block diagram showing the schematic functions of the measuring device according to the second embodiment of the present disclosure.

[0018] Figure 7 This is a schematic diagram of measuring the surface shape of a workpiece using the measuring device of this embodiment. DETAILED DESCRIPTION

[0019] [First embodiment]

[0020] The following, with the attached Figure 1 The embodiments of the present disclosure will now be described.

[0021] Figure 11 is a schematic hardware configuration diagram showing the main parts of the measuring device according to the first embodiment of the present disclosure. In this embodiment, a measuring device 1 that measures the rising and falling positions of the teeth of a gear to be measured is described as an example.

[0022] The CPU 11 included in the measurement device 1 of this embodiment is a processor that controls the entire measurement device 1. The CPU 11 reads a system program stored in the ROM 12 via the bus 22, and controls the entire measurement device 1 according to the system program. The RAM 13 temporarily stores temporary calculation data, display data, various data input from the outside, and the like.

[0023] The nonvolatile memory 14 is composed of, for example, a memory backed up by a battery (not shown), an SSD (Solid State Drive), etc., and maintains the storage state even when the power of the measuring device 1 is turned off. The nonvolatile memory 14 stores programs and data read from the external device 32 via the interface 15, programs and data input via the input device 31, and data calculated based on the signal input from the measuring device 35. The programs and data stored in the nonvolatile memory 14 can also be expanded in the RAM 13 when executed / used. In addition, various system programs such as a well-known analysis program are pre-written in the ROM 12.

[0024] The interface 15 is an interface for connecting the CPU 11 of the measuring device 1 and an external device 32 such as a USB device. For example, a control program, various parameters, etc. used for controlling the industrial machine 3 can be read from the external device 32. In addition, the control program, various parameters, etc. edited in the measuring device 1 can be stored in an external storage unit via the external device 32.

[0025] The display device 30 outputs and displays various data read from the memory, data obtained as a result of executing a program or a system program, etc., via the interface 18. In addition, the input device 31 composed of a keyboard, a pointing device, etc. transmits instructions, data, etc. based on the operator's operation to the CPU 11 via the interface 19.

[0026] The measuring device 35 is connected to the measuring apparatus 1 via the interface 20. The measuring device 35 may be, for example, a distance detector that irradiates laser light and detects the distance by the reflected light. Alternatively, it may be an ultrasonic sensor, etc. The interface 20 converts the signal input from the measuring device 35 into distance data and transmits it to the CPU 11.

[0027] The motor 37 is connected to the measuring device 1 via the interface 21. The interface 21 drives the motor 37 based on the control command of the motor 37 input from the CPU 11. The motor 37 has a built-in position and speed detector, and a position and speed feedback signal from the position and speed detector is fed back. In addition, the position and speed of the motor 37 are controlled based on the control command and the feedback signal.

[0028] Figure 2 Schematic diagram of the shape measurement of a gear using the measuring device 1 of the present embodiment. The measuring device 1 is connected to a measuring instrument 35 and a motor 37. The gear to be measured is mounted on a predetermined rotating shaft. The rotating shaft is rotated by transmitting power from the motor 37 via a power transmission member such as a pulley or a rotating belt. The measuring instrument 35 is arranged at a position away from the rotation center of the gear by a predetermined distance d in the circumferential direction, and facing the rotation center of the gear.

[0029] By such arrangement, the motor 37 is driven to rotate the gear, and the signal from the measuring device 35 is analyzed, thereby, for example, measuring the distance from the measuring device 35 to the tooth tip when the tooth tip of the gear is present at the measuring position, and measuring the distance from the measuring device 35 to the tooth bottom when the tooth bottom of the gear is present at the measuring position. The measuring device 35 outputs a signal indicating the measured distance to the measuring device 1. In the measuring device 1, for example, by subtracting the distance measured by the measuring device 35 from the distance d between the measuring device 35 and the rotation center of the gear, the distance from the rotation center of the gear to the measurement position can be calculated.

[0030] Figure 3 1 is a schematic block diagram showing the functions of the measurement device 1 according to this embodiment. Figure 1 This is achieved by the CPU 11 included in the measurement device 1 executing a system program to control the operation of each unit of the measurement device 1 .

[0031] The measurement device 1 of the present embodiment includes a coordinate value calculation unit 110 , a measurement information recording unit 120 , and a speed abnormality determination unit 130 .

[0032] The coordinate value calculation unit 110 calculates the coordinate values ​​of the rising position and the falling position of the gear teeth based on the signal input from the measuring device 35. The coordinate value calculation unit 110 stores the sequence of distance data calculated based on the signal input from the measuring device 35 in a predetermined buffer memory prepared in advance, for example. Furthermore, when a sequence of distance data indicating a distance shorter than the distance measured previously continues for more than a predetermined number of times, the coordinates of the rising position of the tooth can be calculated based on the sequence of distance data. In addition, when a sequence of distance data indicating a distance longer than the distance measured previously continues for more than a predetermined number of times, the coordinates of the falling position of the tooth can be calculated based on the sequence of distance data. The coordinate value calculation unit 110 displays the calculated coordinate values ​​on the display device 30.

[0033] Figure 4 d1 is a graph showing an example of a sequence of distance data calculated based on a signal input from the measuring device 35. A signal is input from the measuring device 35 to the measuring apparatus 1 at a predetermined period. The distance data calculated based on the input signal is stored in the buffer memory. The buffer memory stores a predetermined number of the latest distance data. At this time, the coordinate value calculation unit 110 monitors the sequence of distance data stored in the buffer memory. Then, after the sequence of distance data of the predetermined distance d1 continues (at Figure 4 At time t i ~t (i+2) ), the distance changes greatly (in Figure 4 At time t (i+3) ~t (i+4) ), and then the sequence of distance data indicating a distance d2 shorter than the prescribed distance d1 continues (in Figure 4 At time t (i+5) ~t (i+7) ). When such a change trend of the distance is detected, the coordinate value calculation unit 110 calculates the coordinate value of the rising position of the gear teeth based on the position of the motor 37 at any time between the time when the distance d1 is last detected and the time when the distance d2 is first detected. The coordinate value of the rising position can be appropriately calculated based on the position of the motor 37 at that time and the reduction ratio of the power transmission component.

[0034] Figure 5 d2 is a graph showing another example of a sequence of distance data calculated based on the signal input from the measuring device 35. The coordinate value calculation unit 110 monitors the sequence of distance data stored in the buffer memory, and after the sequence of distance data of a predetermined distance d2 continues (at Figure 5 At time t j ~t (j+2) ), the distance changes greatly (in Figure 5 At time t (j+3) ~t (j+4)), and then the sequence of distance data indicating a distance d1 longer than the prescribed distance d2 continues (in Figure 5 At time t (j+5) ~t (j+7) ). When such a change trend of the distance is detected, the coordinate value calculation unit 110 calculates the coordinate value of the descending position of the gear teeth based on the position of the motor 37 at any time between the time when the distance d2 is last detected and the time when the distance d1 is first detected. The coordinate value of the descending position can be appropriately calculated based on the position of the motor 37 at that time and the reduction ratio of the power transmission component.

[0035] in addition, Figure 4 , Figure 5 The calculation method of the rising position and the falling position described in the above is an example. Other known calculation methods of the rising position and the falling position can be used as appropriate.

[0036] The coordinate value calculation unit 110 performs the calculation process of the coordinate values ​​of the rising position and the falling position as exemplified above, with the amount of time allocated to each control cycle. In the case where the calculation process of the coordinate value of an rising position or a falling position takes more than a specified time, for example, during the period of detecting the rising position of the teeth of the gear and calculating the coordinates of the rising position, the next falling position sometimes passes through the measurement position of the measuring device 35. Then, when the coordinate value calculation unit 110 finishes calculating the coordinates of the rising position, the distance data recording the falling position disappears from the buffer memory. In this case, the coordinate value of the falling position cannot be accurately calculated. Therefore, the measurement information recording unit 120 and the speed abnormality determination unit 130 detect that such a situation has occurred and notify the user.

[0037] The measurement information recording unit 120 records measurement information related to the time interval at which the shape change of the workpiece occurs. The measurement information may be, for example, the time interval at which the shape change of the workpiece occurs calculated based on the signal input from the measuring device 35. In this case, the measurement information recording unit 120 may monitor the signal input from the measuring device 35, and when the distance calculated based on the signal is within a predetermined time t v The change is greater than a predetermined distance d. v , it is determined that the occurrence of the shape change is detected. And, the measurement information recording unit 120 stores the time when the occurrence of the shape change is detected in the RAM 13 or the non-volatile memory 14, for example. And, the difference between the time when the occurrence of the shape change is detected and the time when the occurrence of the previous shape change is detected can be recorded as the measurement information related to the time interval of the shape change. The measurement information related to the time interval of the shape change only needs to record the shortest time interval. In addition, the measurement information recording unit 120 may also record the time interval of the shape change when the time interval of the shape change detected is a predetermined time terr In the following cases, the time interval is not recorded. By configuring in this way, it is possible to cope with a case where a change in the shape of the workpiece is erroneously detected due to disturbance such as vibration.

[0038] Alternatively, the measurement information may be calculated based on the number of times the shape change of the workpiece occurs within a predetermined time. In this case, the measurement information recording unit 120 prepares a counter for recording the number of times the shape change occurs in, for example, the RAM 13 or the nonvolatile memory 14. p When a shape change occurs during the period of time, the counter is incremented. Then, by p Divide by the elapsed predetermined time t p The value obtained by the counter value after the shape change occurs is recorded as the measurement information related to the time interval at which the shape change occurs. In addition, the measurement information recording unit 120 may also record the time interval at which the shape change occurs when the time interval is a predetermined time t err In the following cases, the shape change is not counted. By configuring in this way, it is possible to cope with a case where a change in the shape of the workpiece is erroneously detected due to disturbance such as vibration.

[0039] Furthermore, the measurement information may be calculated based on the shape specification of the workpiece and the speed of the motor 37. The measurement information recording unit 120 obtains the speed of the motor 37 directly from the motor 37 or based on the speed commanded to the motor 37. Then, based on the obtained speed of the motor 37, the reduction ratio of the power transmission component, and the shape specification of the workpiece (for example, in the case of a gear, the tooth bottom circumference length, the tooth top circumference length, the tooth bottom circle diameter, the tooth top circle diameter, the number of teeth, the tooth pressure, the circle pitch, etc.), the time interval at which the shape change of the workpiece occurs is calculated, and the calculated value is recorded as the measurement information.

[0040] The speed abnormality determination unit 130 determines the abnormality of the relative speed between the workpiece and the measuring device based on the measurement information stored in the measurement information recording unit 120. For example, the speed abnormality determination unit 130 may determine the abnormality of the relative speed between the workpiece and the measuring device when the time interval at which the shape change of the workpiece occurs is shorter than a predetermined threshold value t th If the relative speed between the workpiece and the measuring device is abnormal, the relative speed between the workpiece and the measuring device is judged to be abnormal. th The value of can be calculated by conducting experiments in advance. p It can be preset or based on a predetermined threshold value c thThe speed abnormality determination unit 130 determines that the relative speed between the workpiece and the measuring device is abnormal, and notifies the coordinate value calculation unit 110 that the coordinate value cannot be accurately calculated and the measurement object cannot be accurately evaluated. The coordinate value calculation unit 110 that receives the notification displays the calculated coordinate value and the fact that the coordinate value cannot be accurately calculated and the measurement object cannot be accurately evaluated on the display device 30. At this time, an alarm may be further output.

[0041] The measuring device 1 of the present embodiment having the above-mentioned structure determines whether the coordinate value of the position where the shape of the measuring surface of the measuring object has changed can be accurately calculated, and if it cannot be accurately calculated, the user is notified of the fact. The user who receives the notification can adjust the relative speed between the workpiece and the measuring device, and will measure the shape of the workpiece again. As a result, an accurate measurement result of the workpiece can be used.

[0042] [Second Embodiment]

[0043] The following, with the attached Figure 1 A measurement device according to a second embodiment of the present disclosure will be described below. The measurement device 1 according to this embodiment has the same hardware configuration as that of the measurement device according to the first embodiment.

[0044] Figure 6 1 is a schematic block diagram showing the functions of the measurement device 1 according to this embodiment. Figure 1 This is achieved by the CPU 11 included in the measurement device 1 executing a system program to control the operation of each unit of the measurement device 1 .

[0045] The measuring device 1 of the present embodiment includes a motor speed calculating unit 140 in addition to the coordinate value calculating unit 110 , the measurement information recording unit 120 , and the speed abnormality determining unit 130 .

[0046] The coordinate value calculation unit 110 and the measurement information recording unit 120 of this embodiment have the same functions as those of the measurement device 1 of the first embodiment.

[0047] The speed abnormality determination unit 130 of the present embodiment instructs the motor speed calculation unit 140 to control the speed of the motor when determining that the relative speed between the workpiece and the measuring device is abnormal.

[0048] When the speed abnormality determination unit 130 instructs the motor speed to be controlled, the motor speed calculation unit 140 obtains the measurement information related to the time interval at which the shape change occurs from the measurement information recording unit 120. Then, the obtained measurement information is calculated relative to a predetermined threshold value t thThen, the calculated ratio is multiplied by the currently commanded speed of the motor 37, and the result is set as the new motor speed. At this time, the motor speed calculation unit 140 may further subtract a predetermined margin value v from the calculated motor speed. m The motor speed calculation unit 140 may notify the user of the newly set speed of the motor 37 by displaying it on the display device 30 , for example.

[0049] The measuring device 1 of the present embodiment having the above-mentioned structure determines whether the coordinate value of the position where the shape of the workpiece has changed can be accurately calculated, and if it cannot be accurately calculated, changes the speed of the motor based on the measurement information so that the coordinate value of the position where the shape of the workpiece has changed can be accurately calculated. As a result, an accurate measurement result of the workpiece can be used.

[0050] The measuring device 1 of each embodiment described above determines whether the coordinate value of the position where the shape of the workpiece has changed can be accurately calculated, and if it cannot be accurately calculated, the user is notified of the fact. The user who receives the notification can adjust the relative speed between the workpiece and the measuring device and face the measurement of the shape of the workpiece again. As a result, an accurate measurement result of the workpiece can be used.

[0051] In addition, in the above, the shape of the teeth of the gear is measured as an example of the measurement object. Figure 7 As shown in the example, it can also be used when measuring the surface shape of workpieces other than gears. Figure 7 In the example of , the measuring device 35 is arranged on the measuring surface of the workpiece placed on the workbench. Then, the workbench is moved by driving the motor 37, so that the measuring device 35 scans along the surface of the workpiece. In such a case, by using the measuring device 1 of the present invention, it is also possible to determine whether the moving speed of the workbench is abnormal and notify the user. In the case of making a robot or the like hold the measuring device 35 and scan the measuring surface of the workpiece, the measuring device 1 of the present invention can also be effectively used.

[0052] The present disclosure has been described in detail above, but the present disclosure is not limited to the above-mentioned embodiments. These embodiments can be variously added, replaced, changed, partially deleted, etc. without departing from the scope of the main purpose of the present disclosure, or without departing from the scope of the main purpose of the present disclosure derived from the content recorded in the technical solution of the patent claim and its equivalent. In addition, these embodiments can also be implemented in combination. For example, in the above-mentioned embodiments, the order of each action and the order of each processing are shown as an example, and are not limited to this. In addition, the same applies to the case where numerical values ​​or mathematical formulas are used in the description of the above-mentioned embodiments.

[0053] The following supplementary notes are further disclosed with respect to the above-mentioned embodiment and modified examples.

[0054] (Note 1)

[0055] The measuring device comprises: a coordinate value calculation unit, which calculates the coordinate value of the position where the shape of a measuring surface has changed based on a signal input from a measuring instrument, and the measuring instrument moves the relative position of the measuring surface to the measuring object to measure the change in the shape of the measuring surface; a measurement information recording unit, which records measurement information related to the time interval for the shape change of the measuring surface of the measuring object; and a speed abnormality determination unit, which determines that the relative speed between the measuring surface of the measuring object and the measuring instrument is abnormal when the time interval for the shape change of the measuring surface of the measuring object recorded in the measurement information recording unit is shorter than a predetermined first threshold value, and when the speed abnormality determination unit determines that the relative speed between the measuring surface of the measuring object and the measuring instrument is abnormal, it notifies that the measuring surface of the measuring object cannot be accurately evaluated.

[0056] (Note 2)

[0057] When the time interval during which the shape of the measurement surface of the measurement object changes is shorter than a predetermined second threshold, the measurement information recording unit does not record the measurement information related to the time interval.

[0058] (Note 3)

[0059] The measuring device also includes: a motor speed calculation unit, which calculates the speed of the motor that makes the measuring surface of the measuring object that is not judged to be abnormal and the measuring device move relative to each other based on the measurement information and the first threshold value when the speed abnormality judgment unit judges that the relative speed between the measuring surface of the measuring object and the measuring device is abnormal.

[0060] (Note 4)

[0061] The measuring device changes the speed of the motor to the speed of the motor calculated by the motor speed calculation unit.

[0062] The measuring device according to claim 1, wherein when the speed abnormality determination unit determines that the relative speed between the measuring surface of the measuring object and the measuring device is abnormal, notification is made as an alarm.

[0063] Description of Reference Numerals

[0064] 1. Measurement device

[0065] 11 CPU

[0066] 12 ROM

[0067] 13 RAM

[0068] 14 Non-volatile memory

[0069] 15, 18, 19, 20, 21 interfaces

[0070] 22 Bus

[0071] 30 Display device

[0072] 31 Input device

[0073] 32 External devices

[0074] 35 Measuring device

[0075] 37 Motor

[0076] 110 Coordinate value calculation unit

[0077] 120 Measurement information recording unit

[0078] 130 Abnormal speed determination unit

[0079] 140 Motor speed calculation unit.

Claims

1. A measuring device, characterized in that: have: a coordinate value calculation unit that calculates a coordinate value of a position where a shape of a measurement surface has changed based on a signal input from a measuring device that moves a relative position of the measurement surface to a measurement object to measure the change in shape of the measurement surface; a measurement information recording unit for recording measurement information related to a time interval at which a shape change occurs on the measurement surface of the measurement object; as well as a speed abnormality determination unit for determining that the relative speed between the measurement surface of the measurement object and the measurement device is abnormal when a time interval at which the shape change of the measurement surface of the measurement object recorded in the measurement information recording unit occurs is shorter than a predetermined first threshold value, The speed abnormality determination unit notifies that the measurement surface of the measurement target cannot be accurately evaluated when determining that the relative speed between the measurement surface of the measurement target and the measurement device is abnormal.

2. The measuring device according to claim 1, characterized in that When the time interval during which the shape of the measurement surface of the measurement object changes is shorter than a predetermined second threshold, the measurement information recording unit does not record the measurement information related to the time interval.

3. The measuring device according to claim 1, characterized in that The measuring device further comprises: a motor speed calculation unit which calculates, based on the measurement information and the first threshold value, the speed of the motor for relatively moving the measuring surface of the measuring object that is not determined to be abnormal and the measuring device, when the speed abnormality determination unit determines that the relative speed between the measuring surface of the measuring object and the measuring device is abnormal.

4. The measuring device according to claim 3, characterized in that The measuring device changes the speed of the motor to the speed of the motor calculated by the motor speed calculation unit.

5. The measuring device according to claim 1, characterized in that When the speed abnormality determination unit determines that the relative speed between the measurement surface of the measurement target and the measurement device is abnormal, notification is made as an alarm.

Images