JP6658328B2 - Electrode, static electricity test device and static electricity test method - Google Patents

Description

  The present invention relates to an electrode, an electrostatic test device, and an electrostatic test method.

  Conventionally, immunity evaluation (electrostatic evaluation) of electronic devices with respect to electrostatic discharge from a charged human body or the like is performed using an electrode having a sharp tip or a spherical electrode having a small tip (hereinafter, also referred to as a sharp-shaped electrode). I have. As a technique relating to an electrostatic test using such a sharp electrode, for example, a band static eliminator disclosed in the following patent document is known. This band static eliminator is equipped with a discharge electrode needle whose tip is sharpened. When charging, the discharge electrode needle is set to a high potential and the porous electrode plate is set to a low potential to target ions generated by the discharge electrode needle. On the other hand, during discharge, the discharge electrode needle is set to a high potential of the opposite polarity and the porous electrode plate is set to a low potential or a ground potential, so that ions generated by the discharge electrode needle are applied to the target object surface. It is configured to guide. Thus, the object can be temporarily charged, and when the charged state becomes unnecessary, the charge can be easily and reliably removed without reverse charging.

JP 2015-127665 A

  By the way, when performing static electricity evaluation of a test object such as a newly developed electronic device, a plurality of positions likely to be affected by static electricity are set in advance for the test object, and a predetermined operation mode of the test object is set. An operation of directly applying an applied voltage is performed stepwise at a predetermined number of times for each of the set application locations. For example, there are two levels of operation modes of a high power consumption mode and a low power consumption mode as predetermined operation modes, an application frequency of 10 times per location, and 18 levels of 2 kV from 2 to 20 kV with positive and negative charges. When direct discharge is performed in the static electricity evaluation of the test object, which is an applied voltage and requires 50 places as an application point, the number of direct applications to the test object is about 20,000 times (= 2 × 10 × 18 × 50 times).

  As described above, since the number of times of direct application to one test object is large, the number of work steps is increased, and there is a problem that it takes time to evaluate the entire test object. In addition, since a sharp-shaped electrode is used, there is a possibility that a weak point of the product exists at a position shifted from a predetermined application point, and there is a possibility that an evaluation omission may occur. These problems become more remarkable as the number of application sites increases.

  The present invention has been made to solve the above-described problem, and an object of the present invention is to provide a configuration capable of shortening the evaluation time for an object to be inspected and suppressing omission of evaluation.

  In order to achieve the above object, an invention according to claim 1 is an electrode (20, 20a) used for a discharge gun (12) for an electrostatic test apparatus, wherein a voltage is supplied during a test. A base portion (30), and a discharge portion (40, 40a) provided on the distal end side of the base portion, wherein the discharge portion is made of a conductive elastic material and can be in surface contact with the object to be inspected. Discharge surfaces (43, 43a) are provided.

According to a sixth aspect of the present invention, there is provided a test object (100, 110, 111) using a discharge gun (12) using a first electrode (20, 20a) and a second electrode (120). A static electricity test method for discharging static electricity to the first electrode, wherein the first electrode comprises: a base (30) to which a voltage is supplied at the time of the test; and a discharge unit (40, 40a) provided at a tip end side of the base. The discharge portion is made of a conductive elastic material, provided with a discharge surface (43, 43a) that can make surface contact with the test object, and the second electrode is formed in a sharpened shape. A first inspection area formed to be in local contact with the object to be inspected at a tip end (121) to be contacted with the object to be inspected, the first surface being in contact with the discharge surface of the first electrode. (A1) is set in plurality and the second inspection area is set for each of the first inspection areas. One or more second inspection areas (A2) for contacting the tips of the electrodes are set, and for each of the first inspection areas, a predetermined voltage is applied by contacting the discharge surface of the first electrode. A first step of detecting the presence or absence of an abnormal operation of the inspection object in a state where the abnormal operation is applied to the base in a stepwise manner; and detecting the abnormal operation in the first step of the plurality of first inspection regions. The predetermined voltage was applied stepwise to the base by bringing the tip of the second electrode into contact with each of the second inspection areas included in the first inspection area (A1a). A second step of detecting the presence or absence of the abnormal operation of the test object in a state.
Note that the reference numerals in the parentheses indicate the correspondence with specific means described in the embodiments described later.

  According to the first aspect of the present invention, the discharge portion provided on the distal end side of the base portion is made of a conductive elastic material, and is provided with a discharge surface that can make surface contact with the test object. For this reason, compared with the case where a sharp-shaped electrode is used, the area for applying a voltage to the object to be inspected in one application step is increased. And the weak points of the product can be detected without omission. In particular, the charge transfer occurs in a wide range as the applied area increases, and the radiated electric field strength also increases. Therefore, in a test object having a defect or the like, abnormal operation is easily detected even at a low applied voltage, and abnormal operation is performed in a short time. Can be detected. As described above, it is possible to reduce the number of application points, to detect weak points of the product, and to reduce the applied voltage at the time of detecting an abnormal operation. Therefore, it is possible to shorten the evaluation time for the test object and to suppress the omission of the evaluation.

  According to the second aspect of the present invention, since the discharge portion is formed so that the discharge surface is circular, even when the application area is wide, the voltage is applied uniformly, so that the variation in the applied voltage is suppressed. In addition, it is possible to easily shorten the evaluation time for the object to be inspected and suppress omission of the evaluation.

  According to the third aspect of the present invention, the discharge portion is formed such that a cross-sectional area taken along a plane along the discharge surface is larger than a cross-sectional area of the base portion on the voltage supply side. For this reason, by attaching the electrode of the present invention to the discharge gun on the voltage supply side of the base, the discharge portion can be enlarged without considering attachment to the discharge gun, and the discharge surface can be easily widened.

  According to the fourth aspect of the present invention, since the discharge portion is formed detachably with respect to the base portion, a state in which a voltage is applied by being pressed against the test object so as to be elastically deformed is repeated many times. Even if the discharge part is deteriorated, only the discharge part can be easily replaced.

  According to the fifth aspect of the present invention, since the static electricity test apparatus discharges static electricity to the test object using the discharge gun using the electrode of the present invention configured as described above, the evaluation time for the test object is reduced. It is possible to realize an electrostatic test apparatus capable of shortening the evaluation time and suppressing evaluation omission.

  In the invention according to claim 6, the first electrode includes a base to which a voltage is supplied at the time of a test, and a discharge unit provided on a tip side of the base, and the discharge unit is made of a conductive elastic material. A discharge surface capable of surface contact with the test object is provided. Further, the second electrode is formed so as to locally come into contact with the test object at a tip portion formed in a sharp shape. Then, as a first step, for each first inspection area, the presence or absence of abnormal operation of the inspection object is determined in a state where the discharge surface of the first electrode is brought into contact and a predetermined voltage is applied stepwise to the base. Detecting, as a second step, the tip of the second electrode for each second inspection area included in the first inspection area in which the abnormal operation was detected in the first step among the plurality of first inspection areas. The presence or absence of an abnormal operation of the object to be inspected is detected in a state in which a predetermined voltage is applied stepwise to the base by contacting the parts.

  Thus, the first step functions as a screening step of narrowing down the range in which the abnormal operation occurs using the first electrode. Therefore, if the range in which the abnormal operation occurs is not detected in the first step, the second electrode is used. Since there is no need to perform the applied operation (second step), the evaluation time for the object to be inspected can be reduced. When a range in which an abnormal operation occurs is detected in the first step, an application operation using the second electrode for the second inspection region included in the detected first inspection region (second operation) is performed. Step) is performed. For this reason, compared with the case where the application operation using the second electrode is performed for all the second inspection regions, the area for applying the voltage to the inspection object in one application step is increased. Therefore, it is possible not only to reduce the number of required application points, but also to detect the weak points of the product without omission. In particular, in the first step, the charge transfer occurs in a wide range in accordance with the increase in the applied area, so that the intensity of the radiated electric field also improves. An abnormal operation can be detected in a short time. As described above, since the number of application points can be reduced, the weak point of a product can be detected, and the applied voltage when an abnormal operation is detected can be reduced, a test method capable of shortening the evaluation time for an object to be inspected and suppressing omission of evaluation can be realized. can do.

It is an explanatory view showing the composition outline of the static electricity test device concerning a 1st embodiment. FIG. 2 is a perspective view illustrating a discharge electrode of FIG. 1. FIG. 3 is an explanatory diagram illustrating a detailed shape of a base of FIG. 2. FIG. 3 is an explanatory diagram illustrating a detailed shape of a discharge unit in FIG. 2. It is explanatory drawing which shows the relationship between the hardness of a conductive rubber, and adhesiveness with respect to a plane part and an uneven part. FIG. 3 is an explanatory diagram illustrating a relationship between an IEC standard current waveform and each verification point. It is explanatory drawing which summarized the verification result for every verification point about each conductor resistance value of conductive rubber. It is explanatory drawing which shows the relationship between each conductor resistance value of a conductive rubber, and a peak value (P1). It is explanatory drawing which shows the shape of each member in a radiation electric field simulation, a positional relationship, etc. It is explanatory drawing which shows the electrical relationship of each member in a radiation electric field simulation, etc. FIGS. 11A and 11B are explanatory diagrams showing radiation field simulation results under the conditions in FIGS. 9 and 10. FIG. 11A shows the field intensity including the field emission range, and FIG. 11B shows the change in the maximum field intensity. Is shown. It is explanatory drawing which shows the code scanner used as a to-be-inspected object, FIG.12 (A) shows a top view, FIG.12 (B) shows a bottom view. 4 is a graph showing an applied voltage when a weak point is detected using a discharge electrode according to the present invention and an applied voltage when a weak point is detected using a sharp discharge electrode, for each test object. FIG. 4 is a cross-sectional view schematically showing a field emission range when a voltage is applied to a code scanner using the discharge electrode according to the present invention. It is sectional drawing which shows roughly the electric field emission range at the time of applying a voltage to a code scanner using a sharp discharge electrode. 5 is a flowchart illustrating a flow of an electrostatic test method according to the embodiment. FIG. 17 is an explanatory diagram showing each first inspection area set for the code scanner shown in FIG. 12, where FIG. 17 (A) shows a plan view and FIG. 17 (B) shows a bottom view. FIG. 9 is an explanatory diagram illustrating each second inspection area corresponding to the first inspection area where an abnormal operation has been detected. FIG. 5 is an explanatory diagram illustrating a discharge electrode according to a modification of the first embodiment.

[First Embodiment]
Hereinafter, a first embodiment embodying an electrostatic test apparatus and an electrostatic test method including electrodes according to the present invention will be described with reference to the drawings.
The static electricity test apparatus 10 according to the present embodiment applies immunity to a test object such as an electronic device operating in a predetermined operation mode to evaluate immunity of the test object against electrostatic discharge (ESD). (Electrostatic evaluation). The configuration of the static electricity test apparatus 10 is the same as that of a known static electricity test apparatus except for a discharge electrode 20 described later, and conforms to the international standard IEC61000-4-2.

  As shown in FIG. 1, the static electricity test apparatus 10 mainly includes a static electricity generator 11 and a discharge gun 12, and the static electricity generator 11 outputs static electricity generated in the machine to the discharge gun 12. Function. The discharge gun 12 for the electrostatic test apparatus discharges the static electricity output from the static electricity generator 11 from the discharge electrode 20 and directly applies the static electricity output from the discharge electrode 20 to the device under test in accordance with a predetermined operation by a carried operator. Function.

  Then, in the static electricity test using the static electricity test apparatus 10, a plurality of positions likely to be affected by static electricity are set as application locations for a predetermined operation mode of the test object. An operation of directly applying an applied voltage in a stepwise manner at a predetermined number of times for each application location is performed. In the present embodiment, for example, two levels of operation modes, a high power consumption mode and a low power consumption mode, as a predetermined operation mode, the number of times of application is 10 times for each location, and positive and negative charges every 2 kV from 2 to 20 kV. Increasing 18 levels of applied voltage are assumed.

  Next, the discharge electrode 20, which is a characteristic configuration of the present invention, will be described with reference to FIGS. As shown in FIG. 2, the discharge electrode 20 includes a base 30 to which a voltage is supplied at the time of a test, and a discharge unit 40 provided on a tip side of the base 30. As shown in FIG. 3, the base 30 is made of stainless steel and configured such that a first column 31 and a second column 32 having different diameters are integrated. A screw hole 31 a for assembling with the discharge gun 12 is formed at a predetermined depth on the end face of the first cylindrical portion 31 on the voltage supply side.

  The second cylindrical portion 32 functions as a round flange to which the discharge portion 40 is detachably attached, and is formed so as to be coaxial with the first cylindrical portion 31 and to have a large outer diameter. In the second cylindrical portion 32, a screw hole 33 is formed in the center of the end surface on the tip side (discharge side), and three screw holes 34 reaching the screw hole 33 are formed at equal intervals on the outer peripheral surface. . The base 30 may be made of a member having the same conductivity as stainless steel.

  As shown in FIG. 4, the discharge portion 40 is made of a conductive elastic material, specifically, a conductive rubber having a predetermined hardness and a predetermined conductor resistance value, and has a first cylindrical portion 41 and a second cylindrical portion 41 having different diameters. The column portion 42 is configured to be coaxially integrated. The first cylindrical portion 41 is formed such that its outer diameter can be screwed into the screw hole 33 of the base 30. The second columnar portion 42 has substantially the same outer diameter as the second columnar portion 32 of the base 30, and an end surface on the tip side (discharge side) of the base portion 30 serves as a discharge surface 43 so as to be in predetermined contact with the object to be inspected. It is formed so as to have a circular shape.

  For this reason, in a state where the first cylindrical portion 41 is screwed into the screw hole 33 of the base 30 until the second cylindrical portion 32 comes into surface contact with the second cylindrical portion 42, a flat-head set screw is formed in each screw hole 34. By screwing the respective parts (not shown), the discharge part 40 and the base part 30 are assembled coaxially, and the discharge electrode 20 shown in FIG. 2 is completed. That is, the discharge unit 40 is easily assembled to the base 30 and is detachably formed. In the discharge electrode 20 assembled in this manner, the second cylindrical portion 42 of the discharge portion 40 is coaxial with the first cylindrical portion 31, and has a cross-sectional area cut along a plane along the discharge surface 43. It is formed so as to be larger than the cross-sectional area of the first cylindrical portion 31 on the voltage supply side.

Next, the material of the discharge unit 40 thus configured and the shape of the discharge surface thereof will be described below.
As the discharge unit 40, a conductive rubber having both conductivity and elasticity was employed so that a voltage could be applied in a state in which the discharge unit 40 was in close contact with the object to be inspected.

  First, three hardnesses of “20 °”, “40 °”, and “60 °” are set as selection targets, with the hardness suitable for the discharge unit 40 being about the hardness of a human finger (60 ° or less). did. Then, for each hardness, a cylindrical conductive rubber (Si base, carbon black) having a diameter of 20 mm and a thickness of 5 mm is prepared, and the adhesion to a flat portion such as an LCD and an uneven portion such as a keyboard is measured. Verified. Specifically, when the conductive rubber to which the ink was applied was pressed against the flat portion and the uneven portion via white paper at 9 N assuming the load received from the discharge gun at the time of the test, the conductive rubber appeared on the white paper. The adhesion was verified based on the area of the ink thus obtained. This is because the smaller the area of the ink reflected on the white paper, the lower the adhesion, and there is a possibility that the ink is not suitable as the discharge unit 40 of the present invention.

  As shown in the verification results shown in FIG. 5, when the hardness is “20 °”, the adhesiveness is extremely high with respect to the flat portion and the uneven portion. Moderately high. On the other hand, when the hardness was “60 °”, the adhesion to the flat portion was appropriately increased, while the adhesion to the uneven portion was low. Thereby, regarding the hardness, “20 °” and “40 °” were selected.

  Next, as a conductor resistance value suitable for the discharge part 40, “50Ω · cm”, “25Ω · cm”, “5Ω”, based on a value (50Ω · cm or less) calculated from an allowable error regarding the discharge resistance of the testing machine. · Cm ”were set as selection targets. Under the following selection conditions, the hardness of the conductive rubber D1a having a conductor resistance of 50Ω · cm is 20 °, and the hardness of the conductive rubber D2a having a conductor resistance of 25Ω · cm is 40 °, The hardness of the conductive rubber D3a having a conductor resistance value of 5Ω · cm is set to 60 °. With respect to the current waveform when the conductive rubber for each conductor resistance value is attached to the discharge gun, the peak value (P1), the rise time (P2), and the maintenance of 30 ns with respect to the IEC standard waveform (current waveform) shown in FIG. The value (P3) and the 60 ns maintenance value (P4) were each verified. In this verification, the diameter of the discharge surface was set to φ20 mm.

  As in the verification results shown in FIG. 7, good results were obtained for the rise time (P2), the 30 ns sustain value (P3), and the 60 ns sustain value (P4). On the other hand, as for the peak value (P1), as shown in FIG. 8, the conductive rubber D2a (conductor resistance value: 25 Ω · cm) has a peak value of 30A ± 10%, which is suitable. In the case of the conductive rubber D1a (conductor resistance value: 50Ω · cm), the peak value is less than 27A (30A-10%), and in the case of the conductive rubber D3a (conductor resistance value: 5Ω · cm), the peak value is higher than 33A (30A + 10%). Has also grown. As a result, “25Ω · cm” was selected for the conductor resistance value, and “40 °” was selected for the hardness based on this selection.

  Next, regarding the electric field intensity distribution by the radiation electric field simulation shown in FIGS. 9 and 10, three outer diameters of “φ10 mm”, “φ20 mm”, and “φ30 mm” were set as selection targets as the shape of the discharge surface. The conductive rubber D1b having an outer diameter of the discharge surface of φ10 mm, the conductive rubber D2b having the outer diameter of the discharge surface of φ20 mm, and the conductive rubber D3b having the outer diameter of the discharge surface of φ30 mm have a conductor resistance of 25Ω · cm. The electric field intensity distribution was verified in the arrangement shown in FIG. In addition, the electric field intensity distribution was similarly verified for a conventional sharp discharge electrode (hereinafter, also simply referred to as a sharp discharge electrode).

  The discharge electrode 50 having a thickness d (= 6 mm) employing each of the conductive rubbers D1b to D3b has a distance H1 (= 6 mm) with respect to the main substrate 51 (length L = 149.6 mm, width W = 44.5 mm). ), The main board 51 faces the ground plane 52 at a distance H2 (= 28 mm), and the ground wire 53 of the discharge gun is connected to the ground plane end. , Radiation electric field simulation is performed. As shown in FIG. 10, the capacitance C0 of the discharge gun is 150 pF, the capacitance C1 between the discharge electrode 50 and the main board 51 is 2.37 pF with the conductive rubber D2b, and the main board 51 is connected to the ground. The radiation electric field simulation is performed on the assumption that the capacitance C2 between the planes 52 is 6.67 pF. Also, in FIG. 11A, the verification result at the sharp discharge electrode is indicated by reference symbol D0.

  As can be seen from the verification results shown in FIG. 11A, the larger the outer diameter of the discharge surface (the area of the discharge surface), the wider the field emission range (see the hatched area in FIG. 11A). On the other hand, as shown in the verification result shown in FIG. 11B, the maximum electric field intensity at the conductive rubber D3b is higher than the maximum electric field intensity at the sharp discharge electrode D0, while the electric field at the conductive rubber D2b is higher. Not only the maximum electric field strength but also lower than the maximum electric field strength of the conductive rubber D1b. As one of the reasons, it can be assumed that the capacitance applied by the area applied via the discharge surface increases, while the applied voltage itself decreases. Accordingly, the outer diameter of the discharge surface is preferably not less than φ10 mm and not more than φ30 mm. In the present embodiment, “φ20 mm” was selected.

  Based on such verification results, in the present embodiment, the discharge portion 40 is formed of conductive rubber having a hardness of “40 °” and a conductor resistance value of “25 Ω · cm”, and the outer diameter of the discharge surface 43 is set to “ φ20 mm ”.

  Next, regarding the difference in applied voltage between the static electricity test using the discharge electrode 20 having the discharge part 40 configured as described above and the conventional static electricity test using the sharp discharge electrode 120, see FIGS. I will explain. Here, the sharp discharge electrode 120 is a pin electrode or the like used in a conventional static electricity test apparatus, and has a tip portion 121 formed in a sharp shape so as to locally contact the test object. Is formed.

  In the following description, a relatively simple code scanner 100 without a keyboard or a display screen, a handy terminal 110 with a keyboard or a display screen, and a gripping unit and an antenna unit in addition to a keyboard and a display screen are used as test objects. A handy terminal 111 attached to the outer surface is assumed. In particular, as shown in FIGS. 12A and 12B, the code scanner 100 has two operation buttons 102 and 103 on the upper surface of a housing 101 that forms a substantially box-shaped outer case by an upper case 101a and a lower case 101b. A light emitting unit 105 such as an LED is provided near the reading port 104 on the upper surface thereof, and a speaker 106 is provided at a position distant from the reading port 104. A battery cover 107 that covers a battery (not shown) is attached to the lower case 101b.

  In FIG. 13, the voltage applied when an abnormal operation caused by the weak spot is detected using the sharp discharge electrode 120 is indicated by cross-hatching with respect to the test object having the weak spot, and the discharge electrode 20 is used. In addition, the applied voltage when abnormal operation due to the weak point is detected is indicated by hatching. As can be seen from FIG. 13, in the code scanner 100, when an abnormal operation is detected at 18 kV by using the sharp discharge electrode 120 at a certain weak spot, the abnormal operation is detected at 8 kV by using the discharge electrode 20. Has been detected. Further, in the handy terminal 110, at a certain weak spot, when an abnormal operation is detected at 16 kV by using the sharp discharge electrode 120, an abnormal operation is detected at 8 kV by using the discharge electrode 20. In the handy terminal 111, at a certain weak spot, when an abnormal operation is detected at 14 kV by using the sharp discharge electrode 120, an abnormal operation is detected at 6 kV by using the discharge electrode 20. As can be seen from the results, the use of the discharge electrode 20 can reduce the applied voltage for detecting the abnormal operation caused by the weak point to about 1/2, compared with the case of using the sharp discharge electrode 120. Can detect an abnormal operation.

  This is because, as shown in FIG. 14, the use of the discharge electrode 20 increases the electric field strength and widens the electric field emission range as compared with the case of FIG. 15 in which the sharp discharge electrode 120 is used. This is because the evaluation omission is suppressed and the detection accuracy (detection power) of the abnormal operation caused by the weak point is improved. 14 and 15 schematically show, in a cross-sectional view, a discharge state of the code scanner 100 having the weak spot X1. The main board on which the weak spot X1 and other elements 109 such as a CPU are mounted. Is indicated by reference numeral 108.

Next, an electrostatic test method performed using the electrostatic test apparatus 10 including the discharge electrode 20 according to the present invention will be described in detail with reference to FIGS.
In the static electricity test method according to the present embodiment, as a first step of detecting the presence or absence of an abnormal operation of the inspection object using the discharge electrode 20, an abnormal operation is detected in the first voltage applying step and the first voltage applying step. In this case, a second voltage applying step is prepared as a second step of detecting the presence or absence of an abnormal operation of the test object using the sharp discharge electrode 120. That is, the first voltage application step functions as a screening step of narrowing down the range in which the abnormal operation occurs using the discharge electrode 20 having the wide discharge surface 43. The discharge electrode 20 may correspond to an example of a “first electrode”, and the sharp discharge electrode 120 may correspond to an example of a “second electrode”.

  A plurality of first inspection areas A1 to be brought into contact with the discharge surface 43 of the discharge electrode 20 are set in advance on the test object, and the tip 121 of the sharp discharge electrode 120 is provided for each first inspection area A1. Is set to one or two or more second inspection areas A2 to be contacted. In the first voltage application step, the application operation is performed in a state where the discharge surface 43 is in contact with each of the first inspection areas A1 set as described above. Note that, depending on the object to be inspected, each of the second inspection areas A2 is not limited to being set in advance for each of the first inspection areas A1, and the first inspection area after the abnormal operation of the object to be inspected is detected. One or two or more areas A1 may be set.

Hereinafter, the static electricity test process employing the static electricity test method according to the present embodiment using the code scanner 100 shown in FIG. 12 as an example will be described with reference to the flowchart in FIG.
First, as an initial step (S101 in FIG. 16), a plurality of first inspection areas A1 are set as shown in FIGS. 17A and 17B for the code scanner 100 prepared as the inspection object. Further, for each first inspection area A1, one or more second inspection areas A2 are set.

  Subsequently, a first voltage application step (S103) is performed, and a predetermined voltage is applied to the base 30 by contacting the discharge surface 43 of the discharge electrode 20 for each of the first inspection areas A1 set as described above. With the voltage applied stepwise, the presence or absence of abnormal operation of the test object is detected. Specifically, for each first inspection area A1, a predetermined level of applied voltage (for example, ± 8 kV) for a predetermined operation mode (high power consumption mode and low power consumption mode) at a predetermined number of application times (10 times) ) Is applied directly. Then, when such a voltage is applied, the presence or absence of an abnormal operation of the test object is detected.

  When one level of applied voltage is directly applied at a predetermined number of application times for a predetermined operation mode for each first inspection area A1, unless an abnormal operation of the test object is detected at any application. (No in S105), even if the discharge electrode 20 having high detection accuracy (detection power) is used, no abnormal operation of the test object is detected, so that there is no problem regarding the electrostatic discharge, and the present electrostatic test step ends.

  In this way, when the present static electricity test step is completed only by the first voltage application step, since the discharge electrode 20 having the wide discharge surface 43 is used, the application place is smaller than when the conventional sharp discharge electrode 120 is used. Therefore, the evaluation time for the test object can be shortened.

  On the other hand, if an abnormal operation of the test object is detected even in one place in the first voltage application step (Yes in S105), after detecting the presence or absence of the abnormal operation of the test object in all the first inspection areas A1, The second voltage application step (S107) is performed. Hereinafter, as shown in FIG. 18, a case will be described in which an abnormal operation of the test object is detected in one of the plurality of first inspection areas A1 (see reference numeral A1a in FIG. 18).

  As described above, when an abnormal operation of the object to be inspected is detected in the first inspection area A1a, a second voltage applying step is performed, and the second inspection area A2 included in the first inspection area A1a is applied to each of the second inspection areas A2. On the other hand, in the state where the tip portion 121 of the sharp discharge electrode 120 is brought into contact with and a predetermined voltage is applied stepwise (± 2 to 20 kV) to the base 30 in the same manner as in the first voltage application step, The presence or absence of abnormal operation is detected. The application step for each second inspection area A2 included in the first inspection area A1a corresponds to a conventional static electricity test method using the sharp discharge electrode 120.

  Since the abnormal operation of the inspection object is detected in the first voltage application step, the abnormality of the inspection object in at least one second inspection area A2 is also performed in the subsequent second voltage application step. Motion is detected. As a result, it is possible to specify a detailed application location where an abnormal operation occurs. If no abnormal operation of the object to be inspected is detected in all the second inspection areas A2 set in advance for the first inspection area A1, other parts in the first inspection area A1 or In the vicinity of the outer edge of the first inspection area A1, a point where an abnormal operation occurs can be detected using the sharp discharge electrode 120.

  As described above, in the discharge electrode 20 according to the present embodiment, the discharge portion 40 provided on the distal end side of the base 30 is formed of a conductive rubber having a predetermined hardness and a predetermined conductor resistance as a conductive elastic material. Then, a discharge surface 43 capable of surface contact with the object to be inspected is provided.

  Then, in the static electricity test apparatus 10 according to the present embodiment, static electricity is discharged to the test object by using the discharge gun 12 using the discharge electrode 20 configured as described above.

  For this reason, compared with the case where the sharp discharge electrode 120 is simply used, the area for applying the voltage to the test object in one application step is increased, so that the number of required application locations can be reduced. Not only can it detect the weak points of the product without omission. In particular, the charge transfer occurs in a wide range as the applied area increases, and the radiated electric field strength also increases. Therefore, in a test object having a defect or the like, abnormal operation is easily detected even at a low applied voltage, and abnormal operation is performed in a short time. Can be detected. As described above, it is possible to reduce the number of application points, to detect weak points of the product, and to reduce the applied voltage at the time of detecting an abnormal operation. Therefore, it is possible to shorten the evaluation time for the test object and to suppress the omission of the evaluation.

  In the static electricity test method according to the present embodiment, as the first voltage application step (first step), the discharge surface 43 of the discharge electrode (first electrode) 20 is brought into contact with each of the first inspection areas A1. The presence or absence of abnormal operation of the test object is detected in a state where a predetermined voltage is applied to the base at one level, and as a second voltage application step (second step), a plurality of first inspection areas A1 are detected. For each of the second inspection areas A2 included in the first inspection area A1 in which the abnormal operation has been detected in the first voltage application step, the tip 121 of the sharp discharge electrode (second electrode) 120 is brought into contact with the second inspection area A2 so as to make a predetermined The presence or absence of abnormal operation of the test object is detected in a state in which the voltage is applied stepwise to the base.

  Accordingly, the first voltage application step functions as a screening step of narrowing down the range in which the abnormal operation occurs using the discharge electrode 20. If the range in which the abnormal operation occurs is not detected in the first voltage application step, the sharp discharge electrode Since there is no need to perform the application operation (second voltage application step) using the step 120, the evaluation time for the object to be inspected can be reduced. When a range in which an abnormal operation occurs is detected in the first voltage application step, the application using the sharp discharge electrode 120 for the second inspection area A2 included in the detected first inspection area A1 is performed. Operation (second voltage application step) is performed. For this reason, compared with the case where the application operation using the sharp discharge electrode 120 is performed for all the second inspection regions A2, the area for applying the voltage to the inspection object in one application process is increased. Therefore, not only can the number of required application points be reduced, but also the weak points of the product can be detected without omission. In particular, in the first voltage application step, the charge transfer occurs in a wide range in accordance with the increase of the applied area, so that the intensity of the radiated electric field is also improved. That is, an abnormal operation can be detected in a short time. As described above, since it is possible to reduce the number of application points, detect weak points of a product, and reduce the applied voltage when an abnormal operation is detected, a test method capable of shortening the evaluation time for an object to be inspected and suppressing omission of evaluation is realized. can do.

  In addition, since the discharge portion 40 is formed so that the discharge surface 43 is circular, even when the application area is wide, the voltage is applied uniformly, so that the variation in the applied voltage is suppressed. It is possible to easily shorten the evaluation time for the body and suppress the omission of evaluation.

  Furthermore, the discharge part 40 is formed such that the cross-sectional area of the second cylindrical part 42 cut along a plane along the discharge surface 43 is larger than the cross-sectional area of the first cylindrical part 31 on the base 30 on the voltage supply side. . For this reason, by attaching the discharge electrode 20 to the discharge gun 12 at the first cylindrical portion 31, the discharge portion 40 can be enlarged without considering attachment to the discharge gun 12, and the discharge surface 43 can be easily widened. it can.

  The discharge section is not limited to be formed so that the cross-sectional area cut by a plane along the discharge surface is larger than the cross-sectional area of the base 30 on the voltage supply side. It may be formed to be equal to or smaller than. For example, like the discharge electrode 20a illustrated in FIG. 19, the discharge portion 40a may be formed so as to have a smaller diameter than the first columnar portion 31 together with the second columnar portion 32. In this case, the outer diameter of the discharge surface 43a of the discharge part 40a can be set to, for example, φ10 mm.

  Further, since the discharge unit 40 is detachably formed on the base 30 by using a screw member such as a set screw, a state in which a voltage is applied by being pressed against the object to be inspected so as to be elastically deformed. Even if the discharge unit 40 is deteriorated due to the repeated number of times, only the discharge unit 40 can be easily replaced.

  The discharge unit 40 is not limited to be formed detachably with respect to the base 30 by using a screw member. For example, the discharge unit 40 may be formed with respect to the base 30 by using another detachable configuration such as an engagement piece. It may be formed detachably. Further, depending on the use frequency or the like, the discharge unit 40 and the base unit 30 may be configured to be inseparable by being integrally formed or assembled using an adhesive or the like.

The present invention is not limited to the above embodiment, and may be embodied as follows, for example.
(1) The discharge electrodes 20 and 20a according to the present invention are not limited to being used for a portable discharge gun 12 that can be carried by an operator. For example, a discharge that is movably incorporated in a stationary test apparatus. It may be used for a gun or the like.

(2) The discharge part 40 of the discharge electrode 20 is not limited to being formed of a conductive rubber (Si base, carbon black) having a hardness of “40 °” and a conductor resistance value of “25 Ω · cm”. May be made of a conductive rubber having a thickness of 30 ° or more and 50 ° or less, or a conductive rubber having a conductor resistance of 20 Ω · cm or more and 30 Ω · cm or less. Further, the discharge part 40 has a material characteristic of hardness “40 °” and a conductor resistance value of about 25 Ω · cm (for example, a hardness of 30 ° to 50 ° and a conductor resistance value of 20 Ω · cm to 30 Ω · cm). It may be constituted by a member in which metal powder is blended with various kinds of rubber materials such as a natural rubber and a synthetic rubber.

(3) The discharge surface 43 of the discharge part 40 is not limited to a circular shape of φ20 mm, and may be formed in a circular shape of, for example, φ10 mm or more and φ30 mm or less, depending on the shape of the inspection object. Alternatively, it may be formed in a polygonal shape. Further, the discharge surface 43 of the discharge unit 40 is not limited to being formed in a flat shape, and may be formed in a convex shape according to the shape of the device to be inspected, for example. The same applies to the discharge surface 43a of the discharge unit 40a.

10 electrostatic testing device 12 discharge gun 20, 20a discharge electrode (electrode, first electrode)
30 base 40, 40a discharge section 43, 43a discharge surface 100 code scanner (test object)
120: sharp discharge electrode (second electrode)
A1, A1a: first inspection area A2: second inspection area

Claims (6)

An electrode used for a discharge gun for an electrostatic test device,
A base to which voltage is supplied during the test;
A discharge unit provided on the distal end side of the base,
The electrode, wherein the discharge unit is made of a conductive elastic material and is provided with a discharge surface capable of making surface contact with the test object.   The electrode according to claim 1, wherein the discharge part is formed such that the discharge surface is circular.   3. The electrode according to claim 1, wherein the discharge unit is formed such that a cross-sectional area cut along a plane along the discharge surface is larger than a cross-sectional area on a voltage supply side of the base. 4.   The electrode according to any one of claims 1 to 3, wherein the discharge unit is formed detachably from the base.   An electrostatic test apparatus for discharging static electricity to a test object using a discharge gun using the electrode according to claim 1. An electrostatic test method for discharging static electricity to a device under test using a discharge gun using a first electrode and a second electrode,
The first electrode is
A base to which voltage is supplied during the test;
A discharge unit provided on the distal end side of the base,
The discharge unit is made of a conductive elastic material, and is provided with a discharge surface that can make surface contact with the test object,
The second electrode is
It is formed so as to locally contact the object to be inspected at a tip portion formed in a sharp shape,
A plurality of first inspection areas for contacting the discharge surface of the first electrode are set on the inspection object, and the tip of the second electrode is contacted for each of the first inspection areas. One or more second inspection areas to be set are set,
For each of the first inspection regions, the presence or absence of abnormal operation of the inspection object is detected in a state in which the discharge surface of the first electrode is brought into contact with and a predetermined voltage is applied stepwise to the base. A first step;
For each of the second inspection regions included in the first inspection region in which the abnormal operation has been detected in the first step of the plurality of first inspection regions, the tip of the second electrode is A second step of detecting the presence or absence of the abnormal operation of the test object in a state where the predetermined voltage is applied stepwise to the base by contacting the base;
A static electricity test method comprising:

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