KR102466010B1 - Portable Screw Thread Inspection Equipment and Method Thereof - Google Patents

Abstract

A portable thread inspection device is provided. This portable thread inspection device has an inspection posture correction unit that informs the status of the inspection posture by the gyro sensor to fasten the probe tab to the screw thread of the inspection object in the correct posture, and a probe tab installed to inspect the screw thread of the inspection object. The motor that rotates, the motor driver that operates the motor, the current measuring unit that detects the change in load current of the motor generated in the process of fastening the probe tap to the screw thread of the test object, and the inspection posture status display unit informs the test posture status, and the motor driver and a control unit that transmits an operation signal to and determines whether the screw thread of the object to be inspected is normal or not and the cause of the defect is determined based on the change in load current of the motor detected by the current measuring unit.

Description

Portable Screw Thread Inspection Equipment and Method Thereof

The present invention relates to a portable thread inspection device and method thereof, and more particularly, to a portable thread inspection device and method in which an operator can determine normality and cause of defects by inspecting the processing state of a screw thread of an object to be inspected in an accurate inspection posture. It is about.

In general, various types of nuts are used in the process of fastening machines and devices. Since the fastening force and airtightness of machines and devices depend on the precision of the nut, the accuracy of the diameter, depth, and dimensions of the screw thread formed in the nut is very important for the performance of the machine and device.

Due to the development of technology, most electronic devices are being miniaturized in size or scale, and thus, dustproofing and waterproofing are becoming common to protect concentrated technologies.

As mobile devices also become thinner, faster, and larger in size, bar-type cellular phones with a wide and thin shape are widespread, and dustproof. and a waterproof function are basically adopted.

Devices with such a thin thickness and large surface area are vulnerable to impact and distortion, so their rigidity is required to be supplemented, and assembly errors are also required precisely to maintain dustproof and waterproof properties even in the event of impact and distortion.

However, these devices have a problem in that, during the manufacturing process, assembly errors are likely to be out of tolerance even with a single defect in the screw thread, and enormous damages have to be endured due to poor assembly of the device that is about to be completed due to a defect in one screw thread.

In order to overcome this, workers are inspecting the screw threads themselves while repeating the process of attaching and separating bolts to and from the screw threads of the device, but the tolerance range may vary depending on the individual inspection process, so the inspection process is irregular, and It is pointed out that the working speed is not fast and the fatigue of the worker easily increases.

In addition, there is also a problem in that it is difficult for the operator to accurately couple the bolts in the process of coupling the bolts to the screw threads of the device to be inspected.

Republic of Korea Patent No. 10-1028527

The problem to be solved by the present invention is a portable screw thread inspection in which an operator can determine whether the screw thread of the inspection object is normal or not and the cause of the defect by inspecting the screw thread of the inspection object in an accurate inspection posture using a portable screw thread inspection device. to provide the device.

Another problem to be solved by the present invention is a portable screw thread in which a worker inspects the screw thread of an object to be inspected in an accurate inspection posture using a portable screw thread inspection device to determine whether or not the screw thread of the object to be inspected is normal and the cause of the defect. It is to provide a screw thread inspection method using an inspection device.

The problem to be solved by the present invention is not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, the present invention provides a portable screw thread inspection device. This portable thread inspection device has an inspection posture correction unit that informs the status of the inspection posture by the gyro sensor to fasten the probe tab to the screw thread of the inspection object in the correct posture, and a probe tab installed to inspect the screw thread of the inspection object. The motor that rotates, the motor driver that operates the motor, the current measurement unit that detects the change in load current of the motor that occurs in the process of fastening the probe tap to the thread of the test object, and the test posture correction unit transmits signals about the state of the test posture. , It may include a control unit that transmits an operation signal to the motor driver, and determines whether the screw thread of the test object is normal or not and determines the cause of the defect based on the change in load current of the motor detected by the current measurement unit.

The examination posture correction unit may include a gyro sensor for measuring an angular velocity of the probe tap with respect to the screw thread of the test object and a test posture state display unit for displaying a result calculated from the angular velocity measured by the gyro sensor. The inspection posture status display unit may show the inspection posture status of the probe tap for the screw thread of the inspection object.

The portable screw thread inspection device may include a rotation speed measuring unit that detects the rotation speed of a motor while a probe tap is fastened to a screw thread of an object to be inspected. The control unit may determine whether or not a defect is present according to the depth of the screw thread of the object to be inspected based on the number of revolutions of the motor detected by the rotation speed measurement unit.

The rotational speed measuring unit may include an encoder that detects the rotational speed of the motor and a voltage converter that adjusts voltage between the encoder and the control unit.

The portable screw thread inspection device may include an output unit that outputs whether or not the processing state of the screw thread of the inspection object determined by the control unit is normal and the cause of the defect to an external device. The output unit may use a USB communication method or an RS-232 communication method.

The motor may be a DC motor.

The motor driver can adjust the torque of the motor. The motor driver may be a DC motor driver.

The control unit may transmit a control signal to the motor driver in order to adjust the rotational force of the motor.

The control unit transmits the inspection posture status calculated by the gyro sensor to the inspection posture status display unit, transmits an operation signal to the motor driver, and processes the thread of the inspection object based on the change in load current of the motor detected by the current measurement unit. It may include a microcontroller unit that determines whether a state is normal and a cause of a defect, and a power supply unit that applies power to operate the microcontroller unit.

The current measurement unit includes an ammeter for measuring the load current of the motor, an amplifier for amplifying the load current measured by the ammeter, and an analog/digital converter for converting the load current of the analog value amplified by the amplifier into the load current of the digital value. can include The ammeter may include a shunt resistor. The amplifier may be an operational amplifier.

In addition, in order to achieve the above other object, the present invention provides a screw thread inspection method of a portable screw thread inspection device. This method is to correct the inspection posture so that the probe tap is fastened to the screw thread of the inspection object to be inspected in the correct posture, and to rotate the motor equipped with the probe tap when the inspection signal is input to inspect the screw thread of the inspection object. The current measurement part detects the change in load current of the motor that occurs while the probe tap is fastened to the screw thread of the test object, and the control unit processes the screw thread of the test object based on the change in load current of the motor detected by the current measurement part. It may include determining whether the state is normal and the cause of the defect.

Calibrating the test posture to fasten the probe tab to the screw thread of the object to be inspected in a correct posture may include performing horizontal correction and correcting the test posture by calculating an angular velocity measured by a gyro sensor.

Correcting the examination posture by calculating the angular velocity measured by the gyro sensor may include displaying an incorrect examination posture through the examination posture status display unit and warning of the incorrect examination posture. Warning of an incorrect examination posture may perform a function of informing by vibration.

This method may include setting the rotation direction of the motor by checking left/right directions of the thread of the test object before rotating the motor on which the probe tap is mounted.

This method may include detecting the number of rotations of the motor in the process of fastening the probe tap to the thread of the test object, and determining whether or not there is a defect according to the depth of the thread of the test object by a control unit based on the detected number of rotations of the motor. have.

The method may include detecting a starting point where the probe tab engages the thread of the test object. Detecting a starting point where the probe tap is fastened to the screw thread of the test object may include detecting a change in load current of the motor that occurs when the probe tab starts to be fastened to the screw thread of the test target.

Based on the detected change in the load current of the motor, determining whether the thread of the test object is normal or not and the cause of the defect is the slope of the change in the load current of the motor that occurs while the probe tap is fastened to the thread of the test object, A set range of maximum/minimum or average maximum/minimum values can be used.

This method may include performing a function of visually or audibly notifying the result after determining whether the screw thread of the object to be inspected is normal and the cause of the defect.

This method includes determining whether the thread of the object to be inspected is normal and the cause of the defect, then stopping the motor, rotating the motor in the opposite direction to release the probe tab from the object to be inspected, and stopping the motor. can do.

This method may include outputting whether the processing state of the screw thread of the inspection object determined by the control unit is normal and the cause of the defect to an external device through an output unit.

As described above, according to the solution to the problem of the present invention, a current measuring unit for detecting a change in load current of a motor generated in the process of fastening a probe tap mounted on a motor to a screw thread of an object to be inspected. and a control unit that determines whether the processing state of the screw thread of the inspection target is normal and the cause of the defect based on the change in load current of the motor detected by the current measurement unit, so that the processing state of the screw thread of the inspection target can be automatically inspected. have. Accordingly, a portable screw thread inspection device capable of automatically determining whether the processing state of a screw thread of an object to be inspected is normal and a cause of a defect may be provided.

In addition, according to the means for solving the problem of the present invention, by including a test posture state display unit for informing the test posture state by a gyro sensor so as to fasten the probe tap to the screw thread of the test object to be inspected in a correct posture, An operator can inspect the screw thread of an object to be inspected in an accurate inspection posture using the portable screw thread inspection device. Accordingly, a portable screw thread inspection device capable of correcting a posture so that an operator can inspect a machining state of a screw thread of an inspection target in a correct inspection posture may be provided.

In addition, according to the solution to the problem of the present invention, the current measurement unit detects the change in load current of the motor that occurs in the process of fastening the probe tab mounted on the motor to the screw thread of the test object, and the motor detected by the current measurement unit. The processing state of the thread of the object to be inspected can be automatically inspected by determining whether the processing state of the thread of the object to be inspected is normal and the cause of the defect in the control unit based on the change in the amount of load current. Accordingly, a screw thread inspection method of a portable screw thread inspection device capable of automatically determining whether a screw thread processing state of an object to be inspected is normal and a cause of a defect may be provided.

In addition, according to the means for solving the problem of the present invention, by correcting the inspection posture so that the probe tap is fastened to the screw thread of the inspection object to be inspected in the correct posture, the operator uses a portable screw thread inspection device to correct the screw thread of the inspection object in an accurate inspection posture. can be inspected. Accordingly, a screw thread inspection method of a portable screw thread inspection device capable of correcting a posture so that an operator can inspect the machining state of a screw thread of an inspection target in a correct inspection posture may be provided.

1 is a schematic block diagram illustrating a portable screw thread inspection device according to an embodiment of the present invention.
2 is a three-dimensional view illustrating the appearance of a portable screw thread inspection device according to an embodiment of the present invention.
3A is a block flow chart illustrating a method for correcting a test posture of a portable thread test device according to an embodiment of the present invention.
3B is a three-dimensional view for explaining a configuration of a method for correcting an inspection posture of a portable screw thread inspection device according to an embodiment of the present invention.
4 is a block flow diagram illustrating a method for checking a screw thread using a portable thread checking device according to an embodiment of the present invention.
5A to 5C are graphs for explaining a discrimination algorithm used in a screw thread inspection method using a portable screw thread inspection device according to an embodiment of the present invention.
6A to 6F are graphs showing current waveforms obtained by inspecting screw threads for each of objects to be inspected using the portable screw thread inspection apparatus according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in different forms. Rather, the embodiments introduced herein are provided so that the disclosed content will be thorough and complete and the spirit of the present invention will be sufficiently conveyed to those skilled in the art, and the present invention is only defined by the scope of the claims.

Like reference numbers designate like elements throughout the specification. Accordingly, the same reference numerals or similar reference numerals may be described with reference to other drawings, even if not mentioned or described in the drawings. Also, even if reference numerals are not indicated, description may be made with reference to other drawings.

Terminology used herein is for describing the embodiments and is not intended to limit the present invention. In this specification, singular forms also include plural forms unless specifically stated otherwise in a phrase. As used herein, 'comprises' and/or 'comprising' refers to the presence of one or more other elements, steps, operations and/or devices mentioned. or do not rule out additions. In addition, since it is according to a preferred embodiment, reference numerals presented according to the order of description are not necessarily limited to the order.

An element is said to be 'connected to' or 'coupled to' with another element when it is directly connected to or coupled to another element, or another element in the middle. Includes all cases involving On the other hand, when one component is referred to as 'directly connected to' or 'directly coupled to' another component, it indicates that another component is not intervened. 'and/or' includes each and every combination of one or more of the recited items.

The spatially relative terms 'below', 'beneath', 'lower', 'above', 'upper', etc. It can be used to easily describe the relationship between devices or components and other devices or components. Spatially relative terms should be understood as encompassing different orientations of the device in use or operation in addition to the orientations shown in the figures. For example, when a device shown in the drawings is turned over, a device described as 'below' or 'beneath' another device may be placed 'above' the other device. Accordingly, the exemplary term 'below' may include directions of both down and up. The device may also be oriented in other orientations, and thus spatially relative terms may be interpreted according to the orientation.

In addition, the embodiments described in this specification will be described with reference to cross-sectional views and/or plan views, which are ideal exemplary views of the present invention. In the drawings, the thicknesses of films and regions are exaggerated for effective explanation of technical content. Accordingly, the shape of the illustrative drawings may be modified due to manufacturing techniques and/or tolerances. Therefore, embodiments of the present invention are not limited to the specific shapes shown, but also include changes in shapes generated according to manufacturing processes. Accordingly, the regions illustrated in the drawings have schematic properties, and the shapes of the regions illustrated in the drawings are intended to illustrate a specific shape of the region of the device and are not intended to limit the scope of the invention.

1 is a schematic block configuration diagram for explaining a portable screw thread inspection device according to an embodiment of the present invention, and FIG. 2 is a three-dimensional view of an exterior configuration for explaining a portable screw thread inspection device according to an embodiment of the present invention. to be.

Referring to FIGS. 1 and 2 , the portable screw thread inspection device 100 may largely include a test posture correction unit 110 , a motor 120 , a current measurement unit 140 and a control unit 160 .

The portable screw thread inspection device 100 includes an inspection posture correction unit 110 that informs the inspection posture state by a gyro sensor 112 so as to fasten the probe tab 10 to the screw thread of the inspection object to be inspected in the correct posture, the inspection object A motor 120 for rotating the probe tap 10 mounted to inspect the thread of the motor 120, a motor driver 122 for operating the motor 120, the probe tap 10 is fastened to the screw thread of the inspection object The current measurement unit 140 detects the change in the amount of load current of the motor 120 generated during the process, and transmits a signal about the state of the examination posture to the examination posture correction unit 110, and transmits an operation signal to the motor driver 122. and a control unit 160 for determining whether the processing state of the screw thread of the object to be inspected is normal and the cause of the defect based on the change in the amount of load current of the motor 120 detected by the current measuring unit 140. .

Here, the inspection object may be various parts having a screw thread. That is, in addition to the nut, other parts having threads may also be inspected.

The probe tap 10 may be a bolt-shaped detection member having a screw thread corresponding to a screw thread of an object to be tested.

The test posture correction unit 110 includes a gyro sensor 112 for measuring the angular velocity of the probe tap 10 with respect to the thread of the test object and a test posture status display unit that displays a result calculated from the angular velocity measured by the gyro sensor 112. (114). The examination posture state display unit 114 may show the examination posture state of the probe tap 10 with respect to the screw thread of the object to be tested.

As shown, the test posture state display unit 114 shows a solid cross line corresponding to a calibration line for showing the correct test posture of the probe tap 10 for the screw thread of the test object, and the actual test posture of the probe tap 10 A cross dotted line corresponding to an attitude line showing a test posture state may be displayed. However, it is not limited thereto. The inspection posture status display unit 114 of the portable screw thread inspection device 100 according to an embodiment of the present invention uses various types of display methods to show the correct inspection posture of the probe tap 10 with respect to the screw thread of the object to be inspected. can be hired

The motor 120 may be a direct current (DC) motor.

The motor driver 122 may control the motor 110 while adjusting the rotational force of the motor 10 . The motor driver 132 may be a DC motor driver.

The current measuring unit 140 includes an ammeter 142 for measuring the amount of load current of the motor 120, an amplifier 144 for amplifying the amount of load current measured by the ammeter 142, and an analog amplified by the amplifier 144. It may include an analog/digital converter (A/D converter) for converting a load current amount of a value into a load current amount of a digital value. Ammeter 142 may include a shunt resistor. The amplifier 144 may be an operational amplifier (OP Amp).

The control unit 160 sends a test posture status signal to the examination posture correction unit 110 to display the examination posture status on the examination posture status display unit 114, and a motor driver ( 122) may transmit a control signal.

The controller 160 transmits a signal about the state of the test posture to the test posture correction unit 110, transmits an operation signal to the motor driver 122, and transmits an operation signal of the motor 110 detected by the current measuring unit 140. A microcontroller unit (MCU) 162 that determines the normality of the thread processing state of the inspection object and the cause of the defect based on the change in load current, and power to operate the microcontroller unit 162 A power supply unit 164 for applying may be included. The power supply unit 164 may apply power for driving the motor 120 to the motor driver 122 through the control unit 160 .

The portable screw thread checking device 100 may include a rotation speed measuring unit 150 that detects the rotation speed of the motor 110 while the probe tap is fastened to the screw thread of the inspection object. The control unit 160 may determine whether or not there is a defect according to the depth of the screw thread of the test object based on the number of rotations of the motor 110 detected by the rotation number measuring unit 150 .

The rotational speed measurement unit 150 may include an encoder 152 that detects the rotational speed of the motor 110 and a voltage converter 154 that adjusts the voltage between the encoder 152 and the control unit 160. have. The voltage converter 154 may be a voltage level shifter.

The portable thread inspection device 100 may include an output unit 170 that outputs whether the processing state of the screw thread of the inspection object determined by the control unit 160 is normal and the cause of the defect to an external device. The output unit 170 may use a Universal Serial Bus (USB) communication method or a Recommended Standard (RS)-232 communication method. However, it is not limited thereto. The output unit 170 may use various wired/wireless communication methods capable of transmitting and receiving data to and from external devices. That is, the output unit 170 transmits data on whether the processing state of the screw thread of the inspection object determined by the control unit 160 is normal and the cause of the defect to an external device such as a personal computer (PC). It can serve as a passage for verification.

Although not shown, the portable screw thread inspection device 100 according to an embodiment of the present invention may include a lamp or a display for displaying whether or not the processing state of the screw thread of the inspection target is normal and the cause of the defect.

A portable screw thread inspection device according to an embodiment of the present invention includes a current measurement unit for detecting a change in the amount of load current of a motor generated while a probe tap mounted on a motor is fastened to a screw thread of an object to be inspected, and a motor detected by the current measurement unit. The processing state of the thread of the object to be inspected can be automatically inspected by including a control unit for determining whether or not the thread of the object to be inspected is normal and the cause of the defect based on the change in the amount of load current. Accordingly, a portable screw thread inspection device capable of automatically determining whether the processing state of a screw thread of an object to be inspected is normal and a cause of a defect may be provided.

In addition, the portable screw thread inspection apparatus according to an embodiment of the present invention includes an inspection posture status display unit that informs the inspection posture status by the gyro sensor so as to fasten the probe tap to the screw thread of the inspection object to be inspected in the correct posture, so that the operator It is possible to inspect the screw thread of the object to be inspected in an accurate inspection posture using a portable screw thread inspection device. Accordingly, a portable screw thread inspection device capable of correcting a posture so that an operator can inspect a machining state of a screw thread of an inspection target in a correct inspection posture may be provided.

3A is a block flow chart illustrating a method for correcting an inspection posture of a portable screw thread inspection device according to an embodiment of the present invention, and FIG. It is a three-dimensional view for explaining one configuration.

Referring to FIGS. 3A and 3B , in the method for correcting the inspection posture of the portable thread inspection device 100, the probe tap 10 is placed on the screw thread of the object to be inspected before fastening the probe tap 10 to the screw thread of the object to be inspected. It may include correcting the inspection posture to fasten in the right posture (S100).

Calibrating the test posture (S100) so that the probe tab 10 is fastened to the screw thread of the object to be inspected in the correct posture is to perform horizontal calibration (S10) and measure the gyro sensor (see 112 in FIG. 1). It may include correcting the test posture by calculating the angular velocity (S20, S30, S50, and S60).

Performing the horizontal correction (S10) is, as shown in FIG. 3B, after placing the portable thread inspection device 100 on a horizontal surface, the screw thread of the inspection target of the inspection posture state display unit 114 described above. A dotted cross line corresponding to a posture line showing an actual inspection posture of the probe tap 10 may be matched with a solid cross line corresponding to a correction line for showing a correct inspection posture of the probe tab 10 for the probe tab 10 .

Calculating the angular velocity measured by the gyro sensor and correcting the inspection posture (S20, S30, S50, and S60) allows the operator to adjust the inspection posture for the screw thread of the inspection target with the portable thread inspection device 100 after the horizontal calibration (S10) has been completed. Adjusting (S20), calculating (S30) the angular velocity measured by the gyro sensor, calculating the angular velocity measured by the gyro sensor (S30) by adjusting (S20) the inspection posture for the thread of the test object by the operator If one result is normal aiming (S40), the operator operates the operation switch (S110), and if the result of calculating the angular velocity measured by the gyro sensor (S30) is not normal aiming (S40), check The incorrect posture is displayed on the inspection posture status display unit (S50), and the incorrect inspection posture is warned by a vibration method (S60), so that the operator adjusts the inspection posture for the screw thread of the inspection object (S20) to aim normally (S40). ) may include making it happen.

4 is a block flow diagram illustrating a method for checking a screw thread using a portable thread checking device according to an embodiment of the present invention.

Referring to FIG. 4 , a screw thread inspection method using a portable screw thread inspection device (see 100 in FIG. 1 ) is shown.

The screw thread inspection method is to correct the inspection posture (S100) so that the probe tab (see 10 in FIG. 2) is fastened in the correct posture to the screw thread of the inspection object to be inspected, and the inspection signal to inspect the screw thread of the inspection object is input ( S110) to move the probe tab in the direction of the test object while rotating the motor (see 110 in FIG. 1) to which the probe tab is mounted, and in the current measuring unit (see 140 in FIG. 1), the probe tab is attached to the thread of the test object. Based on the change in the amount of load current of the motor detected in the process of fastening (S120) and the change in the amount of load current in the motor detected by the current measuring unit, the controller (see 160 in FIG. It may include determining whether or not it is normal and the cause of the defect (S130 and S140).

Correcting the test posture (S100) so that the probe tab (see 10 in FIG. 2) is fastened to the screw thread of the object to be tested in the correct posture is the same as described in FIGS. 3A and 3B.

The input (S110) of the inspection signal for inspecting the thread of the inspection object can be performed by applying power for operating the control unit and driving the motor from the power supply unit (see 164 in FIG. 1) of the control unit. have. That is, an inspection signal for inspecting the thread of the inspection object may be input (S110) by the operator pressing the operation switch.

The screw thread inspection method checks the left/right direction of the screw thread of the inspection object before moving the probe tab in the direction of the inspection object (S121) while rotating the motor equipped with the probe tap (S111) to determine the rotation direction of the motor. It may include setting (S112 or S113) to forward or reverse rotation.

Based on the change in the load current of the motor detected by the current measurement unit, the control unit determines whether the processing state of the thread of the test object is normal and the cause of the defect (S130 and S140) is the process of fastening the probe tap to the thread of the test object. It is possible to use the set range of the slope, maximum/minimum value, or average maximum/minimum value of the load current change of the motor that occurs in

Detecting the change in the amount of load current of the motor occurring in the process of fastening the probe tab to the screw thread of the test object in the current measuring unit (S120) moves the probe tab in the direction of the test object while rotating the motor on which the probe tab is mounted (S121). ), detecting the starting point where the probe tap is fastened to the screw thread of the test object (S122), whether the slope of the load current change of the motor generated in the process of fastening the probe tap to the screw thread of the test object is less than the set value Determining (S123), determining whether the maximum / minimum value of the load current change of the motor is within the set range (S124), and determining whether the average maximum / minimum value of the load current change of the motor is within the set range ( It may include (S125) and detecting (S126) the end value of the encoder (see 152 in FIG. 1) indicating the end of the thread test. A loop method may be applied to an algorithm for these detection processes. That is, these determination processes may be continuously and repeatedly performed until the end value of the encoder is detected (S126).

Detecting the starting point where the probe tap is fastened to the screw thread of the test object in the current measuring unit (S122) may be to detect a change in the amount of load current of the motor occurring at the point when the probe tab starts to be fastened to the screw thread of the test target.

Detecting (S120) the change in the load current of the motor that occurs while the probe tap is fastened to the screw thread of the test object in the current measuring unit is the measurement of the change in the load current of the motor that occurs while the probe tap is fastened to the screw thread of the test object. Determining whether the slope is less than or equal to the set value (S123), determining whether the maximum/minimum value of the load current change of the motor is within the set range (S124), and determining whether the average maximum/minimum value of the load current change of the motor It may be to perform at least one of determining whether it is within the set range (S125).

Based on the change in the load current of the motor detected by the current measurement unit, the control unit determines whether the processing state of the thread of the inspection object is normal and the cause of the defect (S130 and S140) is the microcontroller unit of the control unit (see 162 in FIG. 1). ) is set and saved in the process of fastening the probe tap to the screw thread of the test object, the slope of the change in load current of the motor, the maximum value/minimum value, or the standard value for the range of the average maximum/minimum value determines thread defect (S130) Alternatively, it may be determined that the screw thread is normal (S140).

These reference values may be previously set and stored in the microcontroller unit of the controller for the inner diameter and depth of the screw thread of each of the various inspection objects.

The screw thread inspection method determines whether the screw thread of the object to be inspected is normal and the cause of the defect (S130 and S140), then stops the motor (S150) and rotates the motor in the opposite direction (S170) to remove the probe from the object to be inspected. It may include releasing the tab and stopping the motor (S180).

The screw thread inspection method is to visually or audibly notify the result (S161) in a state in which the motor is stopped (S150) after determining whether the screw thread of the inspection object is normal and the cause of the defect (S130 and S140). It may include performing a function. That is, in the screw thread inspection method using the portable screw thread inspection device according to an embodiment of the present invention, the result of determining whether the processing state of the screw thread of the inspection object is normal and the cause of the defect (S130 and S140) is output (S160). can include

If the result of determining whether the thread processing state of the inspection object is normal and the cause of the defect (S130 and S140) is normal, the light emitting diode (LED), which indicates that the thread processing state is normal, turns on. (S162), and in the case of a defect, a light emitting diode indicating that the processing state of the screw thread is defective may be turned on (S163). In addition, in the screw thread inspection method using the portable screw thread inspection device according to an embodiment of the present invention, if the result of determining whether the processing state of the screw thread of the inspection object is normal and the cause of the defect (S130 and S140) is defective, the screw thread is defective. A light emitting diode, which is a lamp indicating that the processing state is defective, is turned on (S163), and a buzzer is operated to sound an additional warning sound (S164).

A screw thread inspection method using a portable screw thread inspection device according to an embodiment of the present invention detects the number of revolutions of a motor in the process of fastening a probe tap to a screw thread of an object to be inspected, and based on the detected number of revolutions of the motor, the control unit detects the object to be inspected. It may additionally include determining whether or not a defect is present according to the depth of the screw thread.

In addition, the screw thread inspection method according to an embodiment of the present invention outputs whether the processing state of the screw thread of the inspection object determined by the control unit is normal and the cause of the defect to an external device through the output unit (see 170 in FIG. 1). may further include

In the thread inspection method using a portable thread inspection device according to an embodiment of the present invention, a current measurement unit detects a change in load current of a motor that occurs while a probe tap mounted on a motor is fastened to a screw thread of an object to be inspected, and Based on the change in the load current of the motor detected by the current measurement unit, the control unit determines whether the screw thread processing state of the inspection target is normal and the cause of the defect, so that the screw thread processing state of the inspection target can be automatically inspected. Accordingly, a screw thread inspection method capable of automatically determining whether a screw thread of an object to be inspected is normal and a cause of a defect may be provided.

In addition, a thread inspection method using a portable thread inspection device according to an embodiment of the present invention corrects an inspection posture so that a probe tap is fastened to a screw thread of an object to be inspected in a correct posture, so that the operator uses the portable screw thread inspection device. Therefore, it is possible to inspect the thread of the object to be inspected in an accurate inspection posture. Accordingly, a screw thread inspection method of a portable screw thread inspection device capable of correcting a posture so that an operator can inspect the machining state of a screw thread of an inspection target in a correct inspection posture may be provided.

5A to 5C are graphs for explaining a discrimination algorithm used in a thread inspection method using a portable screw thread inspection device according to an embodiment of the present invention.

The graphs respectively show current waveforms measured by the current measurement unit (140 in FIG. 1) of the portable thread inspection device (see 100 in FIG. 1) according to an embodiment of the present invention.

In the graph, the x-axis corresponding to the horizontal axis represents the inspection time, and the y-axis corresponding to the vertical axis represents the load current amount of the motor (see 120 in FIG. 1) as a current value.

5A may be a graph corresponding to a set slope value (red solid line) for a change in the amount of load current of a motor generated in a process in which a probe tap (see 10 in FIG. 2 ) is fastened to a screw thread of an object to be inspected.

If the slope of the load current change of the motor in the section where the probe tap is fastened to the thread of the test object (green dotted line circle) exceeds the set value, the test object is judged as defective, and if it is less than the set value, the test object is inspected. can be identified as normal.

5B may be a graph corresponding to a set maximum/minimum value range (red solid line) for a change in the amount of load current of a motor generated in a process in which a probe tap is fastened to a screw thread of an object to be inspected.

If the maximum or minimum value of the load current change of the motor in the section where the probe tap is fastened to the thread of the test object (green dotted circle) is out of the set maximum/minimum value range, the test object is judged to be defective, and then the set range If it is within the range, the inspection target can be determined as normal.

5C may be a graph corresponding to a set average maximum/minimum value range (red dotted line) for a change in load current of a motor generated in a process in which a probe tap is fastened to a screw thread of an inspection object.

If the average value (yellow solid line) of the load current change of the motor in the section where the probe tap is fastened to the thread of the inspection object (green dotted line circle) is out of the set average maximum/minimum value range, the inspection object is judged as defective, and If it is within the set range, the inspection target can be determined as normal.

6A to 6F are graphs showing current waveforms obtained by inspecting screw threads for each of objects to be inspected using the portable screw thread inspection apparatus according to an embodiment of the present invention.

Referring to FIGS. 6A to 6F , graphs showing respective current waveforms obtained by inspecting screw threads for various objects to be inspected are shown.

FIG. 6A is a graph showing a current waveform (green) obtained by driving a motor (see 120 in FIG. 1 ) equipped with a probe tap (see 10 in FIG. 2 ) and inspecting a reference object having a screw thread previously determined to be normal.

This graph may be set and stored in the microcontroller unit (see 162 in FIG. 1 ) of the control unit (see 160 in FIG. 1 ) to serve as a reference value for determining normality or defect with respect to threads of other objects to be inspected.

The first peak corresponds to the amount of load current of the motor that occurs when the motor equipped with the probe tap starts to rotate from a standstill, and the second peak is when the probe tap is fastened to the end of the thread of the reference object. It corresponds to the amount of load current of the motor generated.

FIG. 6B is a graph showing current waveforms (orange) obtained by examining a screw thread of an object having a thread depth of about 10 mm shorter than the thread depth of a reference object previously determined to be normal.

In this graph, it can be seen that a new peak occurs between the first peak and the second peak. Accordingly, it can be seen that the thread of the object to be inspected has a depth that is less than the depth of the thread of the reference object having a thread previously determined to be normal.

FIG. 6C is a graph showing a current waveform (orange) obtained by inspecting a screw thread for an object to be inspected with a poor entry of the screw thread.

In this graph, it can be seen that a new peak occurs immediately after the first peak. Therefore, it can be seen that the entrance of the screw thread of the object to be inspected has a different type of defect from the entrance of the screw thread of the reference target having the screw thread previously determined to be normal.

6D is a graph showing a current waveform (orange) obtained by inspecting a screw thread for an object to be tested in which the screw thread is not formed.

In this graph, it can be seen that a new peak occurs after the second peak. Therefore, it can be seen that the inspection object has a defect in which the thread of the reference object having a thread previously determined to be normal is not formed.

FIG. 6E is a graph showing current waveforms (orange) obtained by examining a screw thread of a test object having a thread depth of about 5 mm that is much shorter than the thread depth of a reference object previously determined to be normal, similar to FIG. 6B.

In this graph, it can be seen that a new peak adjacent to the first peak occurs between the first peak and the second peak compared to FIG. 6B. Accordingly, it can be seen that the screw thread of the object to be inspected has a depth far short of the depth of the screw thread of the reference object having a thread previously determined to be normal.

FIG. 6F is a graph showing current waveforms (orange) obtained by examining a screw thread of an object having a screw thread similar to that of a reference object previously determined to be normal.

In this graph, it can be seen that a new peak adjacent to the second peak occurs between the first peak and the second peak. Accordingly, it can be seen that the thread of the object to be inspected is similar to the thread of the reference object having a thread previously determined to be normal. That is, the processing state of the screw thread of the object to be inspected having the current waveform shown in this graph can be determined to be normal.

In the process of inspecting the thread of the test object, various other current waveforms may appear in addition to the current waveforms of each of the graphs shown in FIGS. 6A to 6F. For these other current waveforms, the cause of the defect in the screw thread of the test object can be identified by analyzing the load current change of the motor generated in the process of fastening the probe tap mounted on the motor to the screw thread of the test object.

That is, the screw thread inspection method using the portable screw thread inspection device according to an embodiment of the present invention detects a change in load current of a motor generated in the process of fastening a probe tap to a screw thread of an object to be inspected, thereby detecting the processing state of the screw thread of the object to be inspected. It is possible to determine whether it is normal or not and various causes of defects.

Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art can implement the present invention in other specific forms without changing its technical spirit or essential features. You will understand that there is Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

10 : Probe tab
100: portable thread inspection device
110: inspection posture correction unit
112: gyro sensor
114: inspection posture status display unit
120: motor
122: motor driver
140: current measuring unit
142: ammeter
144: amplifier
146: analog/digital converter
150: rotational speed measuring unit
152: encoder
154: voltage converter
160: control unit
162: microcontroller unit
164: power supply
170: output unit

Claims (5)

Probe tap mounted to inspect the thread of the inspection object;
a test posture correction unit informing of a test posture state through measurement of angular velocity using a gyro sensor so as to fasten the probe tab to the test object in a correct posture;
a motor rotating the probe tap;
a motor driver operating the motor;
a current measurement unit for detecting a change in the amount of load current of the motor, which occurs while the probe tap is fastened to the screw thread of the test object; and
The inspection posture corrector is notified of the inspection posture status, an operation signal is transmitted to the motor driver, and the processing state of the screw thread of the inspection target is determined based on the change in the amount of load current of the motor detected by the current measurement unit. A portable screw thread inspection device including a control unit that determines whether it is normal or not and the cause of the defect. According to claim 1,
Including a rotational speed measuring unit for detecting the rotational speed of the motor in the process of fastening the probe tap to the screw thread of the test object,
Wherein the control unit determines whether or not there is a defect according to the depth of the screw thread of the test target based on the number of revolutions of the motor detected by the rotation speed measuring unit. According to claim 1,
The inspection posture correction unit,
a test posture state display unit showing a calibration line representing a correct posture of the probe tab with respect to the test object and a posture line representing an actual posture of the probe tab measured through the gyro sensor; and
A portable thread inspection device further comprising a vibration generating unit for notifying by vibration when the inspection posture of the probe tab is in an incorrect posture. to perform horizontal calibration of thread checking devices;
Calculating the angular velocity measured by the gyro sensor to measure the inspection posture of the probe tab with respect to the inspection object;
Correcting a test posture so that the probe tab is fastened to the screw thread of the test object in a correct posture;
rotating a motor equipped with a probe tap when an inspection signal for inspecting the screw thread of the inspection object is input;
detecting a change in the amount of load current of the motor generated in a process in which the probe tap is fastened to the screw thread of the test object by a current measuring unit; and
A method for inspecting a screw thread of a portable screw thread inspection device comprising determining whether the processing state of the screw thread of the inspection target is normal and a cause of the defect, based on the change in the amount of load current of the motor detected by the current measuring unit, in a control unit. . According to claim 4,
The number of revolutions of the motor is detected in the process of fastening the probe tap to the screw thread of the object to be inspected, and based on the detected number of revolutions of the motor, the control unit determines whether the object is defective according to the depth of the thread of the test object. Thread inspection method of a portable thread inspection device comprising the.

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