Measured value processing device

Abstract

To suitably acquire the degree of soiling of a probe.SOLUTION: The measured value processing device according to the present invention acquires, for an object whose value representing an electrical characteristic is smaller than the set value, the degree of soiling of a probe on the basis of the value related to the measured value of the electrical characteristic having been measured by the probe. For the object whose value representing the electrical characteristic is smaller than the set value, the ratio of an impact component attributable to the soiling of the probe to the measured value is higher than for an object whose value representing the electrical characteristic is greater than or equal to the set value. Furthermore, the variation of the measured value is small in many cases. Thus, when based on the value related to the measured value of the object whose value representing the electrical characteristic is smaller than the set value, it is possible to suitably acquire the degree of soiling of the probe.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a measurement value processing device for processing measurements of electrical properties of an object. [Background technology]

[0002] Patent Document 1 describes a measurement value processing device that processes measurement values ​​of the electrical properties of an object. In the measurement value processing device described in Patent Document 1, when the measurement value of the electrical property of the object suddenly increases, it is detected that the probe is dirty and needs to be cleaned. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2023-7002 A Problem to be Solved by the Present Invention

[0004] The object of the present invention is to accurately obtain the degree of contamination of the measuring element.

[0005] In the measurement value processing device of the present invention, the electrical characteristics of an object whose value representing the electrical characteristics is smaller than a predetermined set value are measured using a measuring element, and the degree of contamination of the measuring element is obtained based on a value related to the measurement value of the electrical characteristics of the object.

[0006] For objects whose electrical characteristic values ​​are smaller than the set value, the proportion of the influence of dirt on the probe on the measured value is higher than for objects whose electrical characteristic values ​​are equal to or greater than the set value. Also, the measured values ​​of objects whose electrical characteristic values ​​are smaller than the set value often have smaller variations in the measured values ​​than for objects whose electrical characteristic values ​​are equal to or greater than the set value. As described above, the degree of contamination of the measuring piece can be accurately obtained based on the value associated with the measurement value of an object whose value representing an electrical characteristic is smaller than a predetermined set value. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a perspective view of a placement machine including an electrical characteristic acquisition device equipped with a measurement value processing device according to an embodiment of the present invention; [Figure 2] FIG. 2 is a perspective view of a main part of the electrical characteristic acquisition device. [Figure 3] FIG. 2 is a cross-sectional view of a main part of the electrical characteristic acquisition device. [Figure 4] FIG. 2 is a perspective view of a component as an object whose electrical characteristics are acquired by the electrical characteristic acquisition method. [Figure 5] FIG. 2 is a diagram conceptually showing the structure of the measurement value processing device. [Figure 6] 4 is a flowchart showing an electrical characteristic acquisition program stored in a storage unit of the measurement value processing device. [Figure 7] 10 is a flowchart showing a dirt level acquisition program stored in the storage unit. [Figure 8] 10 is a flowchart showing a part of the electrical characteristic acquisition program. [Figure 9] FIG. 10 is a diagram showing changes in error of the measured values ​​of electrical characteristics acquired by the electrical characteristic acquisition device. EMBODIMENTS OF THE INVENTION

[0008] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A placement machine including an electrical characteristic acquisition device equipped with a measurement value processing device according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings. [Example]

[0009] The placement machine shown in FIG. 1 is for placing components on a circuit board, and includes a main body 2, a circuit board conveying and holding device 4, a component supplying device 6, a head moving device 8, and the like. The circuit board transport and holding device 4 transports and holds a circuit board P (hereinafter referred to as board P) in a horizontal position. In FIG. 1, the transport direction of the board P is the x direction, the width direction of the board P is the y direction, and the thickness direction of the board P is the z direction. The y direction and z direction are the front-to-back and up-to-down directions of the mounting machine, respectively. The x direction, y direction, and z direction are perpendicular to each other. The component supply device 6 supplies electronic components (hereinafter referred to as components) s to be mounted on the board P, and includes multiple tape feeders 14, etc. The head moving device 8 holds a working head 16 and moves it in the x, y, and z directions. The working head 16 has a suction nozzle 18 that picks up and holds the components s.

[0010] The placement machine also includes a camera 20, a measuring device 22, etc. The camera 20 captures an image of the component s held by the suction nozzle 18. Based on the image captured by the camera 20, it is determined whether the component s is to be placed on the circuit board P. The measuring device 22 measures the electrical characteristics of the component s that has not yet been placed on the board P. The electrical characteristics of the component s include L (inductance), C (capacitance), R (resistance), X (reactance), Z' (impedance), etc., and the measuring device 22 measures one or more of these.

[0011] The measuring device 22 is mounted on the placement machine and is attached to the main body of the circuit board conveying and holding device 4 via a storage box 26. A disposal passage 28 is provided between the storage box 26 and the measuring device 22, and the components s whose electrical characteristics have been measured are stored in the storage box 26 via the disposal passage 28.

[0012] 2 and 3, the measuring device 22 includes a main body 30, a mounting base 32, a pair of measuring elements 37 including a stator 34 and a mover 36, a mounting base moving device 38, and an approaching / separating device 40. The main body 30 is attached to the storage box 26. A through-hole 30a that can communicate with the disposal passage 28 is provided in the main body 30.

[0013] The mounting table 32 is where a component s as a measurement object is placed, and includes a component mounting portion 42 and a mounting portion holder 43 that holds the component mounting portion 42. A V-shaped groove 42c is formed in the component mounting portion 42. The V-shaped groove 42c extends in the y-direction, and the component s is placed in the V-shaped groove 42c. A cover 41 is attached to the mounting table 32.

[0014] In this embodiment, the component s has electrodes sp1 and sp2 at both ends as shown in FIG. 4, and can be, for example, a square chip.

[0015] The mounting table moving device 38 moves the mounting table 32. The approaching / separating device 40 moves the pair of probes 34, 36 closer to or farther away from each other (referred to as approaching / separating).

[0016] The stator 34 and the mover 36 have opposing surfaces 34f, 36f, respectively, that face each other, and the part s is gripped by this pair of opposing surfaces 34f, 36f. The stator 34 is held by a stator holder 55, and the stator holder 55 is fixed to the main body 30. The mover 36 is held movably integrally by the mover holder 56, and the mover holder 56 is provided movably relative to the main body 30. The mover holder 56 is moved by an approaching / separating device 40, thereby allowing the mover 36 to approach or separate from the stator 34.

[0017] The opposing surface 36f of the mover 36 has a shape that allows it to enter the V-groove 42c formed in the upper surface of the mounting table 32, in other words, a generally triangular shape that corresponds to the V-groove 42c. Therefore, the component s placed in the V-groove 42c can be held by the mover 36 and the stator 34. The mover 36 also includes a front end portion 36a including an opposing surface 36f, and the front end portion 36a protrudes downward from the intermediate portion 36b. The outer surface of the front end portion 36a is close to the inner surface of the V-groove 42c, but the intermediate portion 36b is far away from the inner surface of the V-groove 42c.

[0018] In this embodiment, the mounting table moving device 38 and the approaching / separating device 40 each include an air cylinder (not shown) as a drive source. The mounting section holder 43, the mover holder 56, etc. are connected to the piston rod of each air cylinder. The movement of the mounting section holder 43, the mover holder 56, etc. is controlled by controlling the supply and exhaust of air in the air chamber of each air cylinder. In addition, air discharged from the air chamber of the air cylinder is supplied to an air passage 60 provided in the stator side member (main body 30, stator holder 55, etc.) or released into the atmosphere. The air supplied to the air passage 60 is supplied to the opposing surface 36f after the electrical characteristics of the component s have been acquired.

[0019] The mounting table 32 and the mover holder 56 are held by a pair of guide rods 86, 87 extending in the y direction so as to be movable relative to each other, and the mover holder 56 is held by a pair of guide rods 88, 89 extending in the y direction so as to be movable relative to the main body 30. As a result, the mounting table 32 and the mover holder 56 are held by the main body 30 so as to be movable relative to each other in the y direction.

[0020] 3, a stopper 92 is provided on the stator side of the mover holder 56, and a stopper 90 is provided on the stator side member. The stopper 92 sets the approach limit between the mover holder 56 and the mounting table 32 (mounting portion holder 43), and the stopper 90 sets the approach limit between the stator 34 (main body 30) and the mounting table 32.

[0021] The mounting table 32 is moved by a mounting table moving device 38 between a position where it abuts against a stopper 90 and a position where it abuts against a stopper 92. When the mounting table 32 is at the position where it abuts against the stopper 92, the mounting table 32 is not between the pair of probes 34, 36, but is spaced apart from both of the pair of probes 34, 36 by a set distance or more.

[0022] The placement machine includes a control device 200. As shown in Fig. 5, the control device 200 includes a controller 202, which is mainly a computer, and a plurality of drive circuits 204. The controller 202 includes an execution unit 210, a storage unit 212, an input / output unit 214, etc., and the board transport and holding device 4, the component supply device 6, the head moving device 8, the measuring device 22, etc. are connected to the input / output unit 214 via the drive circuits 204. A display 216, etc., serving as a notification unit, is also connected. Furthermore, the measurement values ​​of the object measured by the measuring device 22, etc. are input to the input / output unit 214.

[0023] The electrical characteristics of the component s are measured by holding the component s between the facing surfaces 34f, 36f of the pair of probes 34, 36. However, because the facing surfaces 34f, 36f of the pair of probes 34, 36 come into contact with the end faces of the electrodes sp1, sp2 of the component, the facing surfaces 34f, 36f become contaminated as the number of measurements increases. Contamination on the facing surfaces 34f, 36f of the probes 34, 36 increases the contact resistance, which can reduce the measurement accuracy of the electrical characteristics of the component s.

[0024] On the other hand, in the electrical characteristic acquisition device described in Patent Document 1, the target object is a battery, and impedance is measured as an electrical characteristic of the battery. If the measured value suddenly increases, it is acquired as an indication that maintenance is required. Furthermore, paragraph

[0034] of Patent Document 1 states that the battery is manufactured on a production line, and that the impedance of the battery is measured on the production line. However, Patent Document 1 does not state anything about the nominal value of the internal resistance of the battery, such as whether the nominal value of the internal resistance of the battery manufactured on the production line is equal to or less than a set value, or whether it is the same as the battery manufactured on the production line.

[0025] In contrast, in this embodiment, the target component s has a nominal value of resistance or impedance (hereinafter referred to as resistance, etc.) as an electrical characteristic that is smaller than a predetermined set value. When the resistance, etc. of these components s is measured, the error in the measured value is stored. The error is obtained by subtracting the nominal value from the measured value. Then, a moving average of the stored error is obtained, and if the moving average exceeds a threshold value, a notification is issued. If the moving average exceeds the threshold value, it is determined that the degree of contamination of the probes 34, 36 has reached a set level, which requires maintenance.

[0026] The magnitude of the contact resistance caused by dirt on the opposing surfaces 34f, 36f of the probes 34, 36 is roughly the same regardless of the nominal value of the object, provided the degree of dirt is the same. Therefore, for components s with small nominal values ​​such as resistance, the influence of dirt on the probes 34, 36 on the measured value will be greater than for components s with large nominal values. Also, the measured values ​​of components s with small nominal values ​​such as resistance usually have smaller individual variations than the measured values ​​of components s with large nominal values. From the above, the degree of contamination of the probes 34 and 36 can be accurately obtained based on the value related to the measurement value of the component s whose nominal value such as resistance is smaller than the set value.

[0027] Furthermore, the error, which is the value obtained by subtracting the nominal value from the measured value, can be considered to be a magnitude corresponding to the contact resistance caused by contamination on the opposing surfaces 34f, 36f of the probes 34, 36. Therefore, based on the error in the measured value of the component s, it is possible to obtain a better understanding of the change in contact resistance and the degree of contamination than when based on the measured value itself.

[0028] Furthermore, since it is based on error, it is possible to use the measured values ​​of parts with different nominal values, and therefore the degree of contamination of the probes 34 and 36 can be obtained efficiently.

[0029] Note that components s with nominal values, such as resistors, smaller than the set value can be considered to be components s with nominal values ​​greater than 0 but smaller than the set value, and therefore can be considered to be components s with nominal values, such as resistors, that fall within a predetermined set range. Furthermore, if the set value is set to a small value, such as 1-3 Ω, the set range also becomes narrower. As a result, the degree of contamination of the probes 34 and 36 can be more accurately determined based on values ​​related to the measured values ​​of components s with nominal values, such as resistors, that are smaller than the set value.

[0030] The electrical characteristic measurement program shown in the flowchart of FIG. 6 is executed at predetermined cycle times.

[0031] In step 1 (hereinafter abbreviated as S1, the same applies to other steps), it is determined whether a command to measure the electrical characteristics of component s has been issued. For example, if a command to measure the electrical characteristics of component s is issued when a changeover is performed, the determination will be YES. In this way, the components s for which a measurement command has been issued do not necessarily have the same nominal values ​​of resistance, etc., and in many cases these values ​​are different from each other. Furthermore, for components s used in work on this placement machine, the memory unit 212 stores in advance the components s and their electrical characteristics (nominal values ​​that represent the electrical characteristics) in association with each other.

[0032] In S2, the electrical characteristics of the component s are measured and the measured values ​​of the component s are obtained. 8, the work head 16 (suction nozzle 18) picks up the component s supplied by the component supply device 6, moves above the component placement section 42, and releases the component s. As a result, the component s is placed in the V-groove 42c. In S12, the mover 36 is advanced, and the opposing surfaces 34f, 36f of the pair of probes 34, 36 approach each other, thereby gripping the component s placed on the V-groove 42c. In S13, the placement table 32 is moved backward until it abuts against the stopper 92. The placement table 32 is spaced apart from the component s and the front end 36a of the mover 36 by a set distance or more.

[0033] In S14, a set static elimination time is awaited from the time when component s is released from suction nozzle 18 and placed in V-groove 42c. The static elimination time is the time required for the static electricity stored on component s to be removed. If the determination in S14 is YES, electrical characteristics of component s, such as resistance, are measured in S15. The measured values ​​As of resistance, etc. are then displayed on display 216.

[0034] Thereafter, in S16, the mover 36 is retracted, and the mounting table 32 is also retracted. The component s held between the pair of probes 34, 36 is released, and the space between the mover 36 and the stator 34 is connected to the disposal passage 28. The component s is stored in the storage box 26 through the disposal passage 28. As the mover 36 is retracted, air supplied to the air passage 60 is supplied to the opposing surface 36f of the mover 36 from diagonally above. This allows the component s to fall smoothly, even if it is attached to the opposing surface 36f. Furthermore, the cover 41 prevents the component s from scattering. Thereafter, in S17, the mounting table 32 is advanced, and the upper part of the mounting table 32 is opened.

[0035] After the measured value As of the resistance or the like of the component s is obtained, in S3, the nominal value A of the resistance or the like of the component s is read, and it is determined whether the nominal value A is smaller than a set value A0. If the determination is YES, in S4, an error ΔA, which is the value obtained by subtracting the nominal value A from the measured value As, is obtained, and stored in S5. On the other hand, if the determination in S4 is NO, S5 and S6 are not executed.

[0036] The soiling degree obtaining program shown in the flowchart of FIG. 7 is executed at predetermined cycle times. In S21, the error ΔA is read, and a moving average <ΔA>, which is the average value of the error ΔA for each fixed interval, is obtained. The number of errors ΔA in the fixed interval can be a predetermined set number n. In S22, it is determined whether the moving average <ΔA> is greater than a threshold value ΔAth. If the determination is YES, this is notified in S23. For example, information prompting maintenance (for example, an icon indicating maintenance) can be displayed on the display 216. If the determination in S22 is NO, S23 is not executed.

[0037] As shown in the graph in Figure 9, the error ΔA increases as the number of measurements of the electrical characteristics of component s, in other words, the number of components s whose electrical characteristics are measured, increases. Meanwhile, the error ΔA varies widely. Therefore, in this embodiment, a moving average value <ΔA> of the error ΔA is obtained, and when the moving average value <ΔA> exceeds a threshold value ΔAth, a notification is issued that maintenance is required.

[0038] Although it is possible to store measured values ​​in the storage unit 212, in order to obtain errors when the measured values ​​are stored, it is necessary to store the measured values ​​in association with the nominal values. In contrast, storing errors in the storage unit 212 has the advantage of reducing the need to store nominal values. The present invention also includes storing the measured values.

[0039] As described above, in this embodiment, the control device 200 corresponds to the dirt level acquisition unit, the display 216 corresponds to the notification unit, and the control device 200, the display 216, etc. constitute a measurement value processing device. Furthermore, the measuring device 22, the control device 200, the display 216, etc. constitute an electrical characteristic acquisition device.

[0040] In addition to the above-described embodiments, the present invention can be embodied in various forms with various modifications and improvements based on the knowledge of those skilled in the art. [Explanation of symbols]

[0041] 22: Measuring device 32: Mounting table 34: Stator 36: Movable element 200: Control device 212: Memory unit 216: Display Patentable invention

[0042] (1) A measurement value processing device that processes measurement values ​​of electrical characteristics of an object measured by a measuring element, the object has a value representing the electrical characteristic of the object that is smaller than a predetermined set value, The measurement value processing device includes a contamination level acquisition unit that acquires the degree of contamination of the measuring element based on a value related to the measurement value of the electrical characteristic of the object measured by the measuring element.

[0043] The value representing the electrical characteristic of an object can be the nominal value of the electrical characteristic of the object, or a measured value. The nominal value is the public value of the object, and is, for example, a value set by the manufacturer that produced the object. Therefore, the actual measured value of the electrical characteristic of the object is considered to be a value close to the nominal value, but it is not necessarily the same value as the nominal value.

[0044] Furthermore, for objects with small values ​​representing electrical characteristics, the proportion of the influence of contamination on the probe on the measured value is greater than for objects with large values ​​representing electrical characteristics. Therefore, it is possible to accurately estimate the degree of contamination on the probe based on values ​​related to the measured values ​​of objects whose values ​​representing electrical characteristics are smaller than the set value.

[0045] The value related to the measurement value corresponds to at least one of the measurement value and the error in the measurement value.

[0046] The electrical characteristic may be, for example, an impedance, a resistance, or the like, a value that changes depending on the degree of contamination of the probe.

[0047] (2) The measurement value processing device according to (1), wherein the contamination level acquisition unit acquires the contamination level of the measuring element based on an error in the measurement value as a value related to the measurement value.

[0048] The error for a measurement can be obtained, for example, as the measurement minus the nominal value.

[0049] (3) A measurement value processing device according to (2), wherein the contamination level acquisition unit acquires that the contamination level of the measuring element has reached a set level when the error becomes larger than a predetermined threshold value.

[0050] The set level can be, for example, a level at which it is desirable to perform maintenance such as cleaning of the measuring element.

[0051] (4) A measurement value processing device as described in (2) or (3), in which the contamination level acquisition unit acquires a moving average of the error, and when the moving average of the error becomes larger than the threshold value, acquires that the degree of contamination of the measuring element has reached a set level.

[0052] A moving average is the average value of measured values ​​over a certain interval, calculated by shifting the interval. The number of measured values ​​in one interval may be the same or different.

[0053] (5) A measurement value processing device according to any one of (1) to (4), including an alarm unit that notifies the user when the contamination level acquisition unit acquires that the level of contamination of the measuring element has reached a set level.

[0054] The notification unit may be configured to provide visual notification using a display, a lamp, or the like, or to provide auditory notification using a voice output unit, or the like.

[0055] (6) A measurement value processing device described in any one of (1) to (5), wherein the dirt level acquisition unit includes a memory unit that stores an error in the measurement value as a value related to the measurement value when a measurement value of an electrical characteristic of the object is acquired.

[0056] (7) A measurement value processing device described in any one of (1) to (6), wherein the dirt level acquisition unit acquires that the degree of dirt has reached a set level when the measurement value, which is a value related to the measurement value, becomes larger than the initial value of the measurement value by more than a set value.

[0057] The initial value is, for example, the measurement value when measurement of the electrical characteristics of the object begins, and can be the first measurement value. When the change in the measurement value obtained by subtracting the initial value from the measurement value becomes equal to or exceeds a set value, it is determined that the degree of contamination has reached the set level.

[0058] (8) A measurement value processing device that processes measurement values ​​of electrical characteristics of an object measured by a measuring element, the object is one in which a value representing the electrical characteristic of the object is within a predetermined set range, A measurement value processing device including a contamination level acquisition unit that acquires the degree of contamination of the measuring element based on a value related to the measurement value of the electrical characteristic of the object measured by the measuring element.

[0059] The measurement value processing device described in this section can employ any of the technical features described in sections (1) to (7).

[0060] (9) An electrical characteristic acquisition device for acquiring electrical characteristics of an object, a measuring device including the probe; The measurement value processing device according to any one of the above items (1) to (8), An electrical characteristic acquisition device comprising:

[0061] (10) The electrical characteristic acquisition device according to claim (9), wherein the electrical characteristic acquisition device is provided in a mounting machine that mounts electronic components on a circuit board, and acquires the electrical characteristics of the electronic components as the target object.

Claims

1. A measurement value processing device that processes a measurement value of an electrical characteristic of an object measured by a measuring element, the object has a value representing the electrical characteristic of the object that is smaller than a predetermined set value, The measurement value processing device includes a contamination level acquisition unit that acquires the degree of contamination of the measuring element based on a value related to the measurement value of the electrical characteristic of the object measured by the measuring element.

2. 2. The measurement value processing device according to claim 1, wherein the contamination level acquisition unit acquires that the degree of contamination of the measuring element has reached a set level when an error in the measurement value, as a value related to the measurement value, becomes larger than a predetermined threshold value.

3. 3. The measurement value processing device according to claim 2, wherein the contamination level acquisition unit acquires a moving average of the error, and when the moving average of the error becomes larger than the threshold value, acquires that the contamination level of the measuring element has reached a set level.

4. 4. The measurement value processing device according to claim 1, further comprising an alarm unit that notifies the user when the contamination level acquisition unit acquires that the level of contamination of the measuring element has reached a set level.

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