JP7007677B1 - Electronic component inspection equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic component inspection device capable of stably bringing a heated or cooled electronic component to room temperature. SOLUTION: A first measuring unit 11 inspecting an electronic component in a state of being heated or cooled to T1 ° C., and an electronic component inspected by the first measuring unit 11 are inspected at T2 ° C. different from T1 ° C. The second measuring unit 12 and the transport mechanism P for transporting the electronic component given from the first measuring unit 11 toward the second measuring unit 12 are provided, and the transport mechanism P is the temperature of the electronic component. Has a temperature adjusting means p that brings the temperature close to room temperature. [Selection diagram] Fig. 1

Description

The present invention relates to an electronic component inspection device for inspecting electronic components.

Electronic components are subjected to predetermined inspections such as visual inspections and electrical characteristic inspections. Depending on the type of electronic component, it is required to inspect the electronic component at a predetermined temperature, and a specific example thereof is disclosed in Patent Document 1.
The inspection device described in Patent Document 1 is an inspection device in which an electronic component is inspected at room temperature (normal temperature inspection) and a normal temperature test unit is heated around the transfer device for transporting the electronic component to a predetermined temperature. It is equipped with a high temperature test unit that performs high temperature inspection. After the electronic parts are inspected at room temperature, they are transported by a transport device and inspected at high temperature. The high temperature test unit has a heating table and a measuring unit, and the heating table rotates while heating the electronic component placed in the pocket by a heating source, and the electronic component is placed at the measurement position of the electronic component by the measuring unit. The temperature is set to a predetermined level.

Japanese Patent No. 6075663

In the inspection device of Patent Document 1, normal temperature inspection and high temperature inspection are performed on electronic parts, but depending on the electronic parts, low temperature inspection for inspecting electronic parts in a low temperature state is required in addition to normal temperature inspection and high temperature inspection. .. In that case, for example, in order to perform a low temperature inspection after a high temperature inspection, it is necessary to lower the temperature of the electronic component to a predetermined value (normal temperature) before transporting the electronic component that has completed the high temperature inspection to the low temperature inspection position.

However, if an attempt is made to return an electronic component that has become hot to normal temperature only by transporting it in a normal temperature atmosphere by a transport device, it is necessary to secure a sufficiently long transport time by the transport device, and the transport distance for returning to room temperature is long. There was a problem that the length became long and the size of the device was increased.
The present invention has been made in view of such circumstances, and an object of the present invention is to provide an electronic component inspection apparatus capable of stably bringing a heated or cooled electronic component to room temperature.

The electronic component inspection apparatus according to the present invention according to the above object includes a first measuring unit that inspects an electronic component in a state where it is heated or cooled to T1 ° C., and the electronic component that is inspected by the first measuring unit. A second measuring unit for inspecting at T2 ° C. different from T1 ° C., and a transport mechanism P for transporting the electronic component given from the first measuring unit toward the second measuring unit. The transport mechanism P includes an air blowing means for blowing air having a temperature different from T1 ° C. onto the electronic component to bring the temperature of the electronic component close to room temperature, and a plurality of electronic components moving in the same direction. An electronic component carrier and a plurality of electronic component carriers arranged in parallel in a direction orthogonal to the moving direction of the electronic component are moved in a direction orthogonal to the moving direction of the electronic component, and one electronic component is used. It is provided with a driving means for arranging the upstream end of the electronic component of the carrier in the moving direction at a position where the electronic component from the first measuring unit can be acquired .

In the electronic component inspection device according to the present invention, the transport mechanism P for moving the electronic component given from the first measuring unit toward the second measuring unit provides an air blowing means for bringing the temperature of the electronic component close to room temperature. Since it has, it is possible to stably bring the heated or cooled electronic component to room temperature.

It is explanatory drawing of the electronic component inspection apparatus which concerns on one Embodiment of this invention. It is explanatory drawing of the parts transfer unit. It is explanatory drawing of the electronic component transport body of the transport mechanism P. It is explanatory drawing of the transport mechanism which concerns on the modification.

Subsequently, an embodiment embodying the present invention will be described with reference to the attached drawings, and the present invention will be understood.
As shown in FIG. 1, the electronic component inspection device 10 according to the embodiment of the present invention is a measurement unit 11 which is an example of a first measurement unit for inspecting an electronic component W in a state of being heated to T1 ° C. The measurement unit 12, which is an example of the second measurement unit that inspects the electronic component W inspected by the measurement unit 11 at T2 ° C different from T1 ° C, and the electronic component W given by the measurement unit 11 are measured. A transport mechanism P for transporting toward the unit 12 is provided. Hereinafter, it will be described in detail.

The electronic component W to be inspected by the electronic component inspection device 10 is, for example, a diode, a transistor, a capacitor, an inductor, and an IC (Integrated Circuit). In the present embodiment, the electronic component W is plate-shaped and rectangular in a plan view, but the shape of the electronic component W is not limited.

As shown in FIG. 1, the electronic component inspection device 10 conveys the electronic component W to the measurement unit 11 in addition to the measurement units 11 and 12 and the transfer mechanism P, acquires the electronic component W from the measurement unit 11, and transfers the electronic component W to the transfer mechanism P. It includes a component transfer unit 14 that moves toward the measurement unit 14, and a component transfer unit 15 that transfers the electronic component W that has passed through the transfer mechanism P to the measurement unit 12 and acquires it from the measurement unit 12.

In addition to this, in the electronic component inspection device 10, the electronic component inspection device 10 obtains the electronic component W acquired from the measurement unit 12 by the component transfer unit 15 from the component transfer unit 15 and conveys the electronic component W, and the electronic component W that has passed through the transfer mechanism Q. A measuring unit 18 which is an example of a third measuring unit for inspecting the electronic component W transported by the component transporting unit 17 at T3 ° C. and returning the electronic component W to the component transporting unit 17 is provided. ing. However, T3 ° C is a temperature different from both T1 ° C and T2 ° C. In the present embodiment, T1> T3> T2, T1 ° C is higher than normal temperature (natural temperature without heating or cooling) (for example, 100 ° C or higher and 200 ° C or lower), and T2 ° C is lower than normal temperature. The temperature (for example, −80 ° C. or higher and −20 ° C. or lower) and T3 ° C. are normal temperatures (for example, 0 ° C. or higher and 40 ° C. or lower).

Therefore, the component transfer unit 14, the transfer mechanism P, the component transfer unit 15, the transfer mechanism Q, and the component transfer unit 17 are provided in the order of transfer of the electronic component W.
As shown in FIGS. 1 and 2, the parts transfer unit 14 (the same applies to the parts transfer units 15 and 17) is a horizontally arranged disk-shaped rotating body 20 that rotates around a vertically arranged rotation shaft 19. , A plurality of arms 21 connected to the rotating body 20 and arranged radially, a vertically long nozzle 22 attached to each arm 21 so as to be able to move up and down, and a rotating body 20 together with each arm 21 and each nozzle 22. It has a motor 23 that rotates intermittently.

The nozzle 22 can attract the electronic component W at the lower end portion, and repeatedly rotates and pauses around the rotation shaft 19 accompanying the operation of the motor 23 to convey the attracted electronic component W. As shown in FIG. 2, some of the stop positions of the arm 21 and the nozzle 22 were fixed to the outer periphery of the disk-shaped plate 25 horizontally supported by the support 24 above the stop position of the arm 21. A plurality of support members 26 and a movable body 28 attached to the support member 26 so as to be able to move up and down are provided.

Each movable body 28 descends by the operation of the motor 29 fixed to the support member 26, comes into contact with the nozzle 22, and pushes down the nozzle 22. A coil spring 30 for raising the lowered movable body 28 is attached to the support member 26, and a coil spring 31 for raising the lowered nozzle 22 is attached to the nozzle 22. In FIG. 2, only two sets of the arm 21, the nozzle 22, and the coil spring 31 are described, and the description of the other arm 21, the nozzle 22, and the coil spring 31 is omitted. Further, in FIG. 2, the support member 26, the movable body 28, the motor 29, and the coil spring 30 are shown one by one, but in the present embodiment, a plurality of these are provided.

As shown in FIGS. 1 and 2, a rotary table 32 provided in the measuring unit 11 is arranged below one of the stop positions of the nozzle 22 provided with the movable body 28 above, and the nozzle 22 is stopped. Between the position and the rotary table 32, a rotary machine 34 is provided that acquires the electronic component W adsorbed on the nozzle 22 and stores the electronic component W in the pocket 33 formed in the rotary table 32. In addition, in FIG. 1, the description of the rotary machine 34 and another rotary machine having the same design as the rotary machine 34 is omitted.

As shown in FIG. 2, the rotary machine 34 has a disk-shaped rotating body 36 that rotates about a horizontal rotating shaft 35 attached to a support (not shown) and a plurality of arms 37 fixed to the rotating body 36. Each has a plurality of attached chucks 38. Each chuck 38 long in the radial direction of the rotating body 36 is arranged radially around the rotating body 36, and can move forward and backward in the radial direction of the rotating body 36 with respect to the rotating body 36. Each chuck 38 arranged at an equal pitch can attract the electronic component W at one end (the end far from the center of the rotating body 36) by the suction force.

The rotating body 36 is intermittently rotated by the operation of a motor (not shown), and repeats rotation and pause by the arrangement pitch of the chuck 38. At the 12 o'clock position, the chuck 38 acquires the electronic component W from the nozzle 22 in the descending state, and at the 6 o'clock position, the chuck 38 is given a driving force of a motor (not shown) and descends, and electronically enters the pocket 33 of the rotary table 32. Insert the part W. The lowered chuck 38 is raised by the coil spring 39.

As shown in FIG. 1, the measuring unit 11 inspects the electronic component W housed in the pocket 33 of the rotary table 32 in addition to the rotary table 32 that rotates intermittently around the rotary shaft 32a arranged vertically (as shown in FIG. 1). In the present embodiment, the inspection means 40 for (electrical characteristic inspection) is provided. A heater 27 is provided on the rotary table 32, and the heater 27 heats the electronic component W in the pocket 33 to a predetermined temperature (T1 ° C.) before being transported to a position where the inspection by the inspection means 40 is performed.

The electronic component W that has been inspected by the inspection means 40 moves to just below the chuck 38 by the rotation of the rotary table 32, and is attracted to the chuck 38.
The chuck 38 that has acquired the electronic component W from the rotary table 32 moves to the 12 o'clock position, the nozzle 22 arranged at the ascending position descends, and the electronic component W is acquired from the chuck 38 arranged at the 12 o'clock position. Adsorb.

The electronic component W adsorbed on the nozzle 22 moves together with the nozzle 22 by the operation of the motor 23, is conveyed to the position where the rotary machine having the same design as the rotary machine 34 is provided, and is given to the rotary machine. .. It should be noted that the electronic component W may be transferred between the component transfer unit 14 and the measurement unit 11 by using a mechanism having a design different from that of the rotary machine 34, and the nozzle 22 of the component transfer unit 14 rotates. Needless to say, the electronic component W may be directly inserted into the pocket 33 of the table 32, and the electronic component W may be directly acquired from the pocket 33 of the rotary table 32.

The rotary machine that has acquired the electronic component W from the nozzle 22 gives the electronic component W to the component relay means 41 of the transport mechanism P shown in FIG. As shown in FIG. 3, the transport mechanism P (same for the transport mechanism Q) has a plurality of electronic components W to be sent from the component relay means 41 in addition to the component relay means 41 (five in the present embodiment). 42, a shift means 43 for translating each electronic component carrier 42, and a component delivery means 44 for sending the electronic component W provided by the electronic component carrier 42 toward the component transfer unit 15. There is.

As shown in FIGS. 1 and 3, each electronic component carrier 42 is linear, is provided horizontally, and is arranged in parallel. Inside each electronic component carrier 42, as shown in FIG. 3, a transport space 45 in which the electronic component W is housed, a plurality of air flow passages 46 communicating with the transport space 45, and air communicating with each air flow passage 46. The inflow space 47 is formed. The transport space 45 is long in the longitudinal direction of the electronic component transport body 42, and is open at both ends of the electronic component transport body 42 in the longitudinal direction. The electronic component W sent out from the component relay means 41 enters the transport space 45 from the upstream end (one end in the longitudinal direction) of the transport space 45. The temperature of the electronic component W is higher than normal temperature when it enters the transport space 45.

Each of the plurality of air flow passages 46 is linear and is provided at a position below the transport space 45, with an upper end portion communicating with the transport space 45 and a lower end portion communicating with the air inflow space 47. The upper end of each air flow passage 46 is inclined so as to be closer to the component delivery means 44 than the lower end.
The air inflow space 47 formed on the lower side of the air flow passage 46 is long in the longitudinal direction of the electronic component carrier 42, and the upper side communicates with each air flow passage 46.

The transport mechanism P includes an air blowing means (vacuum pump in this embodiment) 49 connected to a tube 48 communicating with the air inflow space 47. The air blowing means 49 sends air at room temperature to the transport space 45 via the tube 48, the air inflow space 47, and the plurality of air flow passages 46, and has a temperature of less than T1 ° C. (this) to each electronic component W in the transport space 45. In the embodiment, air at room temperature) is blown to move each electronic component W toward the downstream end portion (the other end in the longitudinal direction) of the transport space 45, and each electronic component W is blown with air at room temperature. The temperature of the above is brought close to normal temperature (in this embodiment, the temperature is lowered by 60 ° C. or more).

Therefore, in the present embodiment, the transport mechanism P has the air blowing means 49 as the temperature adjusting means p for bringing the temperature of the electronic component W close to the normal temperature (in the present embodiment, the temperature is brought to the normal temperature).
Here, the electronic component W that has moved from the electronic component carrier 42 to the component delivery means 44 is conveyed to the measurement unit 12 via the rotary mechanism and the component transfer unit 15 having the same design as the rotary mechanism 34 (FIG. 1). (See), the transport mechanism P also uses the blowing of air to the electronic component W by the air blowing means 49 to move the electronic component W toward the measuring unit 12.
Further, the electronic component transport body 42 has a stopper 50 that closes the downstream side of the transport space 45 so that the electronic component W arranged in the transport space 45 does not come out of the transport space 45.

As shown in FIG. 3, the shift means 43 has a screw shaft 53 parallel to the linear guides 51, 52, guides 51, and 52 arranged orthogonally to each electronic component carrier 42 in a plan view. A movable block 54 attached to the lower part of each electronic component carrier 42 and moving along the guide 51, and a movable block 55 attached to the lower part of each electronic component carrier 42 and moving along the guide 52. It is provided with a nut block 56 fixed to the lower part of each electronic component carrier 42 and mounted on the screw shaft 53, and a driving means 57 for rotationally driving the screw shaft 53.

The drive means 57 can rotate the screw shaft 53 clockwise and counterclockwise, and rotate the screw shaft 53 to move the nut block 56 along the screw shaft 53. Each electronic component carrier 42 moves (laterally moves) in a direction orthogonal to the longitudinal direction of each electronic component carrier 42 together with the movable blocks 54 and 55 as the nut block 56 moves. The drive means 57 moves a plurality of electronic component transport bodies 42, and moves the upstream end portion of one electronic component transport body 42 to a component delivery position (that is, a measurement unit) in which the electronic component W is sent out from the component relay means 41. The electronic component W from 11 is placed at a position where it can be acquired).

In the electronic component carrier 42 whose upstream end is arranged at the component delivery position, the electronic component W is intermittently transferred from the component relay means 41 to the transport space 45 in a state where the downstream side of the transport space 45 is closed by the stopper 50. Sent. The electronic component W sent into the transport space 45 moves in the transport space 45 by the air from the air blowing means 49. At the timing when the upstream side of the stopper 50 in the transport space 45 of one electronic component carrier 42 is filled with the electronic component W, each electronic component carrier 42 is moved by the operation of the drive means 57, and the other electronic component carrier 42 is moved. The upstream end of the 42 is arranged at the component feeding position, and the electronic component W is fed from the component relay means 41 into the transport space 45 of the electronic component carrier 42.

This process is repeated until the upstream side of the stopper 50 of the transport space 45 of all the electronic component transport bodies 42 is filled with the electronic component W. During this time, the electronic components W in the transport space 45 of each electronic component transport body 42 continue to be cooled by the air from the air blowing means 49 sent to the transport space 45. After that, the electronic component carrier 42 in which the electronic component W is first sent from the component relay means 41 to the transport space 45 is placed in a state where the downstream end is arranged at the component delivery position, and the stopper 50 of the electronic component carrier 42 is placed. Is opened so that the electronic component W is sent out from the downstream end of the transport space 45 to the component sending means 44. The electronic component W has reached room temperature by the time it is sent out from the downstream end of the transport space 45 by blowing air.

By arranging the electronic component carriers 42 in parallel in this way, the electronic component W is brought closer to room temperature without lengthening the transport distance of one electronic component carrier (the temperature of the electronic component W is lowered by a predetermined value or more). It is possible to secure a transport time for raising the size of the electronic component W, and it is possible to prevent the electronic component inspection device from becoming large in size because the electronic component W is brought close to room temperature.

As shown in FIG. 1, the electronic component W sent out from the transport space 45 to the component delivery means 44 is a rotary machine having the same design as the rotary machine 34, a parts transfer unit 15, and a rotary machine having the same design as the rotary machine 34. Is conveyed to the measuring unit 12. The measuring unit 12 includes a rotary table 60 in which the pockets 59 are formed at equal pitches, and an inspection means 61 for inspecting the electrical characteristics of the electronic component W in the pocket 59. The rotary table 60 has a Pelche element 62, and cools the electronic component W in the pocket 59 to a predetermined temperature (T2 ° C.) before being transported to a position where the inspection by the inspection means 61 is performed.

Here, since the Pelche element 62 cools the electronic component W from a normal temperature state, the electronic component W is located at a position where the inspection by the inspection means 61 is performed, as compared with cooling the electronic component W from a temperature higher than the normal temperature. By the time it is transported, the temperature of the electronic component W can be stably lowered to a predetermined value. The electronic component W that has been inspected by the inspection means 61 is returned from the rotary table 60 to the component transfer unit 15 via the rotary machine having the same design as the rotary machine 34, and is returned to the component transfer unit 15 via the rotary machine having the same design as the rotary machine 34. Will be transported to.

The transport mechanism Q has the same design as the transport mechanism P, and brings the electronic component W given in this order from the measuring unit 12 through the rotary machine, the component transport unit 15, and the rotary machine closer to room temperature (in the present embodiment, the electronic component W). It has a temperature adjusting means q (air blowing means in this embodiment) (which raises the temperature of the above by 20 ° C. or more). The electronic component W brought close to room temperature by the transport mechanism Q (in this embodiment, brought to room temperature) is sent to the component transport unit 17 via a rotary machine having the same design as the rotary machine 34, and is sent to the component transport unit 17. The electrical characteristics are inspected (that is, measured) at T3 ° C. (in this embodiment, normal temperature) by the measuring unit 18 provided in the vicinity of the component transport unit 17 while being attracted to the nozzle 22 of the 17th. The unit 18 inspects the electronic component W inspected by the measuring unit 12 at T3 ° C.). Therefore, the transport mechanism Q moves the electronic component W toward the measurement unit 18.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and all changes in conditions that do not deviate from the gist are within the scope of the present invention.
For example, the transport mechanism P (the same applies to the transport mechanism Q) may have only one electronic component transport body. When the transport mechanism P (the same applies to the transport mechanism Q) has a plurality of electronic component transport bodies, the plurality of electronic component transport bodies do not need to be arranged in parallel. Further, as shown in FIG. 4, a plurality of electronic component carriers 64 are attached to the side surfaces of a columnar rotating body 65 whose axes are horizontally arranged, and one electronic component carrier 64 is formed by the rotation of the rotating body 65. , The electronic component W from the first measuring unit may be arranged at a position where it can be acquired.
The electronic component carrier is not limited to a linear shape, and may be, for example, an arc shape.

Further, it is not necessary to adopt an air blowing means as the temperature adjusting means p (the same applies to the temperature adjusting means q). For example, the temperature adjusting means p is attached to the electronic component carrier 64 as shown in FIG. The heat sink 66 may be adopted. That is, the temperature adjusting means p (the same applies to the temperature adjusting means q) does not simply bring the electronic component W, which is in a state higher or lower than normal temperature, close to normal temperature in a normal temperature atmosphere, but actively dissipates heat from the electronic component W. Alternatively, it may be any as long as it positively absorbs heat from the electronic component W and brings it close to room temperature.

Further, the transport mechanisms P and Q do not have to have the same design, and the first, second, and third measurement units do not have to have the same design.
Needless to say, the first measuring unit (the same applies to the second and third measuring units) is not limited to that of the above-described embodiment, and for example, a rotating body to which nozzles are radially attached is centered on a horizontal axis. It may rotate to.

The first, second, and third measurement units do not have to be arranged at the same height position. For example, the second measurement unit is arranged directly under the first measurement unit, and the second measurement is performed. A third measuring unit may be arranged directly under the unit. In this case, transfer mechanisms P and Q having a long electronic component transfer in the vertical direction are adopted.

Further, when the inspection of the electronic component needs to be performed only in the state of T1 ° C. and the state of T2 ° C., the third measuring unit and the transport mechanism Q are omitted. In this case, for example, there is a pattern of T1 ° C> normal temperature> T2 ° C and a pattern of T2 ° C> normal temperature> T1 ° C.
In this regard, when the inspection of the electronic component is performed in the state of T1 ° C., the state of T2 ° C. and the state of T3 ° C., in addition to the pattern of T1 ° C.> T3 ° C. (= normal temperature)> T2 ° C. of the above embodiment, for example. , T2 ° C> T3 ° C (= normal temperature)> T1 ° C. In the case of the pattern of T2 ° C.> T3 ° C. (= normal temperature)> T1 ° C., in the first measuring unit, the electronic component is cooled and inspected at T1 ° C. Further, by setting the temperature of the air blown by the air blowing means to the electronic component to be higher than T1 ° C., the electronic component can be brought close to normal temperature. Therefore, the air blowing means blows air having a temperature different from T1 ° C. onto the electronic component to bring the electronic component closer to room temperature.

Here, for example, in the order of transporting the electronic parts, the measurement unit a for normal temperature inspection, the transport mechanism j, the measurement unit b for inspection at a temperature higher than normal temperature, the transport mechanism k, and the measurement for measurement at a temperature lower than normal temperature. When the unit c is provided, the measurement units b and c are the first and second measurement units, respectively, the transfer mechanism k is the transfer mechanism P, and the measurement unit a is the first, second, and third measurement units. It does not correspond to any of the units, and the transfer mechanism j does not correspond to any of the transfer mechanisms P and Q.

10: Electronic component inspection device, 11, 12: Measuring unit, 14, 15: Parts transport unit, 17: Parts transport unit, 18: Measurement unit, 19: Rotating shaft, 20: Rotating body, 21: Arm, 22: Nozzle , 23: Motor, 24: Support, 25: Plate, 26: Support member, 27: Heater, 28: Movable body, 29: Motor, 30, 31: Coil spring, 32: Rotating table, 32a: Rotating shaft, 33 : Pocket, 34: Rotary machine, 35: Rotating shaft, 36: Rotating body, 37: Arm, 38: Chuck, 39: Coil spring, 40: Inspection means, 41: Parts relay means, 42: Electronic component carrier, 43 : Shift means, 44: Parts delivery means, 45: Transport space, 46: Air flow passage, 47: Air inflow space, 48: Tube, 49: Air blowing means, 50: Stopper, 51, 52: Guide, 53: Screw Shaft, 54: Movable block, 55: Movable block, 56: Nut block, 57: Drive means, 59: Pocket, 60: Rotating table, 61: Inspection means, 62: Pelche element, 64: Electronic component carrier, 65: Rotating body, 66: heat sink, P: transport mechanism, Q: transport mechanism, W: electronic component

Claims (2)

The first measuring unit that inspects electronic components in a state where they are heated or cooled to T1 ° C.
A second measuring unit that inspects the electronic component inspected by the first measuring unit at a T2 ° C different from the T1 ° C.
The electronic component given from the first measuring unit is provided with a transport mechanism P for transporting the electronic component toward the second measuring unit.
The transport mechanism P includes an air blowing means for blowing air having a temperature different from T1 ° C. onto the electronic component to bring the temperature of the electronic component close to room temperature, and a plurality of electronic components in which the electronic component moves in the same direction. A carrier and a plurality of electronic component carriers arranged in parallel in a direction orthogonal to the moving direction of the electronic component are moved in a direction orthogonal to the moving direction of the electronic component, so that the electronic component carrier is one. An electronic component inspection apparatus comprising: a driving means for arranging an upstream end portion of the electronic component in a moving direction at a position where the electronic component from the first measuring unit can be acquired . In the electronic component inspection device according to claim 1, the air blowing means also uses the blowing of air toward the second measuring unit of the electronic component. ..

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