JP2017223453A - Inspection jig - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspection jig suitable for utilization for a power semiconductor which facilitates exchange of a contact member.SOLUTION: An inspection jig has a surface and a rear face, has a relay adapter on which a cavity passing from the surface to the rear face is formed, a relay terminal that is mounted on the relay adapter and has a circuit connection portion arranged on the surface side and a connection portion provided on the cavity, and a contact provided so as to be insertable-extractable to from the rear face side, where one of the connection portion and the contact has an elastic portion, and the elastic portion exerts an elastic force to the other out of the connection and the contact to connect the connection portion and the contact.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an inspection jig, and more particularly to an inspection jig suitable for use in a power semiconductor.

  Patent Document 1 discloses an inspection jig. The inspection jig includes a contact. The contact includes a contact member having elasticity and a contact member for contacting the inspection target, and a relay member for guiding expansion and contraction of the contact member. The contact is covered with a holding body that holds the contact.

JP 2014-163786 A

  In the inspection jig, it may be necessary to replace the contact member. In the inspection jig shown in Patent Document 1, when removing the contact member, it is necessary to remove the holding body that covers the contact and further remove the contact member from the relay member. For this reason, it takes time to replace the contact member.

  The present invention has been made to solve the above-described problems, and an object thereof is to obtain an inspection jig in which the contact member can be easily replaced.

  The inspection jig according to the present invention includes a front surface and a back surface, a relay adapter in which a cavity penetrating from the front surface to the back surface is formed, and is attached to the relay adapter and disposed on the front surface side. A relay terminal provided with a circuit connection part and a connection part provided in the cavity, and a contact provided so as to be insertable / removable from the back side, and one of the connection part and the contact is an elastic part And the elastic portion exerts an elastic force on the other of the connecting portion and the contact, whereby the connecting portion and the contact are connected.

  In the inspection jig according to the present invention, the relay terminal and the contact are connected by elastic force. For this reason, the relay terminal and the contact can be easily attached and detached. Further, the wiring for connecting to the inspection circuit is connected to a circuit connecting portion provided in the relay terminal. For this reason, when exchanging a contact, it is not necessary to remove wiring. Furthermore, the back side of the relay adapter is provided so that the contact can be inserted and removed. From the above, it is possible to replace the contact by inserting and removing from the back side with the relay terminal attached to the relay adapter. Accordingly, the contact can be easily replaced.

It is a perspective view of the inspection jig concerning Embodiment 1 of the present invention. FIG. 2A is a perspective view of the inspection jig according to Embodiment 1 of the present invention. FIG. 2B is an enlarged view of the inspection jig according to Embodiment 1 of the present invention. It is a front view of the inspection jig concerning a comparative example. It is an enlarged view of the inspection jig which concerns on the modification of Embodiment 1 of this invention. FIG. 5A is a cross-sectional view of an inspection jig according to Embodiment 2 of the present invention. FIG. 5B is a cross-sectional view of an inspection jig according to a modification of Embodiment 2 of the present invention. FIG. 6A is a cross-sectional view in the xz plane of the inspection jig according to Embodiment 3 of the present invention. FIG. 6B is a cross-sectional view in the yz plane of the inspection jig according to Embodiment 3 of the present invention. FIG. 7A is a perspective view of an inspection jig according to Embodiment 4 of the present invention. FIG. 7B is a diagram for explaining the structure of an inspection jig according to Embodiment 4 of the present invention. It is sectional drawing of the jig | tool for an inspection which concerns on Embodiment 5 of this invention.

  An inspection jig according to an embodiment of the present invention will be described with reference to the drawings. The same or corresponding components are denoted by the same reference numerals, and repeated description may be omitted.

Embodiment 1 FIG.
FIG. 1 is a perspective view of an inspection jig according to Embodiment 1 of the present invention. The inspection jig 100 includes a relay adapter 10. A relay terminal 20 is attached to the relay adapter 10. The relay adapter 10 includes a circuit board 12 on the surface 11. The circuit board 12 is attached to the surface 11 side of the relay adapter 10 with screws. The circuit board 12 includes a circuit pattern 16. The circuit board 12 includes a passive component 18. In the present embodiment, the passive component 18 is a capacitor that connects the two relay terminals 20.

  An inspection circuit (not shown) for inspecting an inspection object is connected to the relay terminal 20. The circuit pattern 16 is changed according to the inspection content. The passive component 18 may be a resistance element. The type, arrangement, and number of the passive components 18 are changed according to the inspection contents. In the present embodiment, the inspection contents can be easily changed by exchanging the circuit board 12. The relay adapter 10 is formed of a material containing polyacetal. By using polyacetal, it is possible to ensure insulation and improve workability. Moreover, the relay adapter 10 is good also as what is formed with the material containing a baking material. Even when a baking material is used, insulation can be ensured and workability can be improved.

  FIG. 2A is a perspective view of the inspection jig according to Embodiment 1 of the present invention. In FIG. 2A, the circuit board 12 is omitted for convenience. A cavity 15 is formed in the relay adapter 10. The cavity 15 penetrates from the front surface 11 to the back surface 19 of the relay adapter 10.

  The relay terminal 20 includes a circuit connection portion 21 at one end and a connection portion 22 at the other end. The circuit connection portion 21 is exposed from the surface 11. The relay terminal 20 is attached to the relay adapter 10. A method of attaching the relay terminal 20 to the relay adapter 10 is not limited. For example, the relay terminal 20 and the relay adapter 10 may be joined with an adhesive. In addition, the relay terminal 10 may be fixed by the relay adapter 10 contacting the relay terminal 20 in the vicinity of the surface 11 and the relay terminal 20 being sandwiched between the relay adapters 10. The circuit connection unit 21 is connected to an inspection circuit (not shown) by wiring 42. The circuit connection portion 21 is connected to the wiring 42 by solder. The connecting portion 22 is provided inside the cavity 15. The connection part 22 is rod-shaped.

  A contact 30 is connected to the relay terminal 20. The contact 30 includes an elastic part 31 at one end. The relay terminal 20 and the contact 30 are connected by the elastic part 31 and the connection part 22 contacting. The other end 32 of the contact 30 is a part that comes into contact with the inspection object. The contact 30 includes a curved portion 34 between the elastic portion 31 and the other end 32. By the bending portion 34, the contact 30 comes into contact with the inspection object with an elastic force. For this reason, the contact between the inspection object and the contact 30 can be stabilized.

  FIG. 2B is an enlarged view of the inspection jig according to Embodiment 1 of the present invention. FIG. 2B is an enlarged cross-sectional view of the broken line portion 40 of FIG. 2A. In the present embodiment, the elastic portion 31 has a bifurcated fork shape. The bifurcated fork shape is formed of two metal pieces having elastic force. The elastic portion 31 sandwiches the rod-shaped connecting portion 22 from both sides. The elastic part 31 exerts an elastic force on the connection part 22. In a state where the elastic part 31 and the connection part 22 are connected, the connection part 22 pushes the interval between the two metal pieces included in the elastic part 31. For this reason, the elastic force acts in the direction in which the two metal pieces forming the fork shape are closed. The direction in which the elastic force works is the x-axis direction shown in FIG. 2B. In the present embodiment, the contact portion 30 and the connection portion 22 are connected by the elastic portion 31 exerting an elastic force on the connection portion 22.

  Further, the connection portion between the elastic portion 31 and the connection portion 22 is formed inside the cavity 15. The cavity 15 is provided so that the side wall 13 of the relay adapter 10 and the elastic part 31 do not come into contact with each other when the elastic part 31 and the connection part 22 are connected. For this reason, it becomes possible to insert / remove the contact 30 from the back surface 19 side. The relay terminal 20 and the contact 30 are connected by press-fitting the contact 30 into the connecting portion 22 in the z-axis direction from the back surface 19 side. Further, the contact 30 can be removed from the relay terminal 20 by pulling out the contact 30 from the back surface 19 side in the negative direction of the z-axis.

  In the inspection jig 100 according to the present embodiment, the relay terminal 20 and the inspection circuit are connected by the wiring 42. On the other hand, a structure in which the contact is directly connected to the wiring without providing the relay terminal is conceivable. FIG. 3 is a front view of an inspection jig according to a comparative example. The inspection jig 600 according to the comparative example includes a metal pin 630. The metal pin 630 is fixed to a fixing portion 660 having an insulating property. The product 670 is an inspection target. The metal pin 630 contacts the product terminal 672 included in the product 670 with elasticity.

  The metal pin 630 is connected to the inspection circuit via the wiring 642. The wiring 642 and the metal pin are connected by solder. A passive component 618 is attached to the inspection jig 600 according to the inspection content. The passive component 618 may need to be attached in the vicinity of the contact portion with the product 670. At this time, it may be necessary to attach the passive component 618 to the metal pin 630 with solder.

  When replacing the metal pin 630 of the inspection jig 600, it is necessary to remove the wiring 642 and the passive component 618. The wiring 642 and the passive component 618 are connected to the metal pin 630 with solder. Therefore, it takes time to remove the wiring 642 and the passive component 618. In addition, after the new metal pin 630 is attached, it is necessary to attach the wiring 642 and the passive component 618 again. Therefore, it takes time to replace the metal pin 630.

  On the other hand, in the inspection jig 100 according to the present embodiment, the wiring 42 and the passive component 18 are connected to the relay terminal 20. Therefore, it is not necessary to remove the wiring 42 and the passive component 18 when replacing the contact 30. The contact 30 and the relay terminal 20 are connected by press-fitting. Therefore, the contact 30 can be replaced by inserting and removing the contact 30 from the back surface 19 side. For this reason, exchange of the contact 30 becomes easy.

  FIG. 4 is an enlarged view of an inspection jig according to a modification of the first embodiment of the present invention. In the inspection jig 800 according to the modification of the present embodiment, the relay terminal 820 is provided with an elastic portion. The relay terminal 820 includes a circuit connection portion 821 at one end and a connection portion 822 at the other end. The connecting portion 822 is provided with a bifurcated fork-shaped elastic portion. The contact 830 includes a linear portion 831 at one end connected to the connection portion 822. The straight line portion 831 has a rod shape. The shape of the contact 830 is the same as that of the contact 30 except for the straight portion 831. The connecting portion 822 sandwiches the straight portion 831 from both sides. In the inspection jig 800 according to the modification, the contact portion 822 and the connection portion 822 are connected by the connection portion 822 exerting an elastic force on the linear portion 831. Therefore, also in the inspection jig 800 according to the modification, the contact 830 can be replaced by inserting and removing the contact 830 from the back surface 19 side.

  In the present embodiment, the elastic portion 31 has a bifurcated fork shape, and the connection portion 22 has a rod shape. On the other hand, the shape of the elastic part 31 and the connection part 22 may be different as long as the connection by press-fitting is possible. For example, the elastic portion 31 may include three or more metal pieces having elastic force, and the metal pieces may be disposed so as to surround the connection portion 22.

  In the present embodiment, a part of the elastic portion 31 is accommodated in the relay adapter 10 in a state where the contact 30 and the relay terminal 20 are connected. On the other hand, in a state where the contact 30 and the relay terminal 20 are connected, all the elastic portions 31 may be accommodated in the cavity 15. Alternatively, the connecting portion 22 may be disposed below the back surface 19 so that the contact 30 and the connecting portion 22 are connected below the back surface 19.

  In the present embodiment, one relay terminal 20 is arranged in one cavity 15. As a modified example, the cavity 15 may be elongated in the y-axis direction of FIG. 2, and a plurality of relay terminals 20 may be arranged in one cavity 15. Moreover, in this Embodiment, the side wall 13 and the elastic part 31 do not contact in the state in which the elastic part 31 and the connection part 22 were connected. As a modification, the width of the cavity 15 may be set so that the elastic part 31 inserted into the cavity 15 is pressed by the side wall 13 from both sides in the x-axis direction. In this structure, the elastic part 31 and the connection part 22 contact by the elastic part 31 being pressed from the both sides by the side wall 13.

  In the present embodiment, the contact 30 includes a bending portion 34. On the other hand, the contact 30 may have another shape as long as it includes the elastic portion 31 at one end and a portion that contacts the inspection target at the other end 32. For example, the bending portion 34 may not be provided. In the present embodiment, the relay adapter 10 includes the circuit board 12, but the circuit board 12 may not be provided depending on the inspection contents. These modifications can be applied as appropriate to inspection jigs according to the following embodiments. Since the inspection jig according to the following embodiment has much in common with the first embodiment, the difference from the first embodiment will be mainly described.

Embodiment 2. FIG.
FIG. 5A is a cross-sectional view of an inspection jig according to Embodiment 2 of the present invention. FIG. 5A is a cross-sectional view in the yz plane of the inspection jig 200 according to the present embodiment. The inspection jig 200 according to the present embodiment includes a relay terminal 220 and a contact 230. The shapes of relay terminal 220 and contactor 230 in the xz plan view are the same as relay terminal 20 and contactor 30 of the first embodiment. FIG. 5A shows a state where the contact 230 is removed from the relay terminal 220.

  In the inspection jig 200 according to the present embodiment, the length of the connecting portion 222 in the y-axis direction is larger than the length of the contactor 230 in the y-axis direction. Here, the y-axis direction is a first direction parallel to the surface 211 of the relay adapter 210 and perpendicular to the direction in which the elastic portion 231 exerts an elastic force. Note that the direction in which the elastic portion 231 exerts an elastic force is the x-axis direction as in the first embodiment.

  Also in this embodiment, the contact 230 and the relay terminal 220 are connected by press-fitting the elastic portion 231 into the connection portion 222 from the back surface 219 side. In the present embodiment, the connecting portion 222 is provided with a wide width in the y-axis direction. Therefore, when the contactor 230 is connected, even if a displacement in the y-axis direction occurs between the contactor 230 and the relay terminal 220, the connection is possible. In addition, when a positional deviation in the y-axis direction occurs between the relay terminal 220 and the inspection target, it is possible to correct the positional deviation by adjusting the position where the contact 230 is attached.

  FIG. 5B is a cross-sectional view of an inspection jig according to a modification of Embodiment 2 of the present invention. In the inspection jig 200, the length of the connecting portion 222 in the y-axis direction is larger than the length of the contactor 230 in the y-axis direction. For this reason, as shown to FIG. 5B, the contactor 230 can be provided in multiple numbers in the y-axis direction. By overlapping a plurality of contacts 230, the contact area with the inspection object is increased. Therefore, it is possible to reduce the contact resistance between the contact 230 and the object to be inspected as compared with the case where one contact 230 is connected to the relay terminal 220. Accordingly, it is possible to improve the energization capability.

  In the present embodiment, as in the first embodiment, the contactor 230 includes the elastic portion 231. As a modification, the connecting portion 222 may include an elastic portion. In this case, the connection part 222 is formed of two pieces of metal having a length in the y-axis direction larger than the length of the contactor 230 in the same direction and having an elastic force. The two metal pieces are arranged so as to overlap in the x-axis direction. The metal piece provided in the connecting portion 222 sandwiches the contact 230 from both sides. In FIG. 5B, four contactors 230 are provided so as to overlap each other. The number of contacts 230 to be stacked is changed in consideration of contact resistance.

Embodiment 3 FIG.
FIG. 6A is a cross-sectional view in the xz plane of the inspection jig according to Embodiment 3 of the present invention. The inspection jig 300 according to the present embodiment includes a first relay terminal 320 and a second relay terminal 327. The structure of the first relay terminal 320 and the second relay terminal 327 is the same as that of the relay terminal 220 of the second embodiment. The second relay terminal 327 is disposed at a position shifted from the first relay terminal 320 in the x-axis direction.

  The inspection jig 300 includes a first contact 330, a second contact 333, and a third contact 336. In the first contactor 330, the position of the elastic part 331 is shifted in the x-axis direction as compared with the contactor 230. Other structures are the same as the contact 230. The structure of the second contact 333 and the third contact 336 is the same as that of the contact 230.

  FIG. 6B is a cross-sectional view in the yz plane of the inspection jig according to Embodiment 3 of the present invention. The first relay terminal 320 includes a first connection part 322. The second relay terminal 327 includes a second connection part 329. The lengths of the first connection part 322 and the second connection part 329 in the y-axis direction are larger than the lengths of the first contact 330, the second contact 333, and the third contact 336 in the y-axis direction. The first contactor 330 is connected to the first relay terminal 320. The second contact 333 and the third contact 336 are connected to the second relay terminal 327 in a state where they overlap each other in the y-axis direction. In portions other than the elastic portions 331, 334, and 337, the first contact 330, the second contact 333, and the third contact 336 are disposed so as to overlap in the y-axis direction.

  In the present embodiment, the first contact 330, the second contact 333, and the third contact 336 are disposed so as to overlap in the y-axis direction at the other ends 332, 335, and 338 that are contact portions with the inspection target. Therefore, the 1st contactor 330, the 2nd contactor 333, and the 3rd contactor 336 contact the same terminal with which a test subject is provided. On the other hand, the elastic part 331 of the first contactor 330 is arranged so as to be shifted in the x direction with respect to the elastic parts 334 and 337 of the second contactor 333 and the third contactor 336. Therefore, it becomes possible to connect the first contactor 330 to the first relay terminal 320 different from the second relay terminal 327 to which the second contactor 333 and the third contactor 336 are connected.

  The first relay terminal 320 and the second relay terminal 327 are connected to another inspection circuit via the wirings 342 and 344. Therefore, in the inspection jig 300, the first contact 330, the second contact 333, and the third contact 336 contact the same terminal, while the relay terminal side is divided into a plurality of paths. At this time, it is possible to flow current from a plurality of current paths to the terminal to be inspected. Therefore, a large current can be passed to the inspection object. In the present embodiment, the position of the relay terminal provided in the inspection jig 300 in the x-axis direction is divided into two locations. On the other hand, the position of the relay terminal may be divided into three or more locations.

Embodiment 4 FIG.
FIG. 7A is a perspective view of an inspection jig according to Embodiment 4 of the present invention. The inspection jig 400 according to the present embodiment includes a plurality of relay terminals 420. The relay terminal 420 is attached to the relay adapter 410. On the surface 411 of the relay adapter 410, the plurality of relay terminals 420 are linearly provided along the y-axis. Further, the circuit connection portions 421 of the relay terminals 420 are arranged in a staggered arrangement in plan view. The circuit connection portion 421 is connected to an inspection circuit (not shown) via wirings 442 and 444.

  FIG. 7B is a diagram for explaining the structure of an inspection jig according to Embodiment 4 of the present invention. FIG. 7B is a diagram in which adjacent relay terminals 420 among the plurality of relay terminals 420 included in the inspection jig 400 are arranged for comparison. The circuit connection part 421 of the relay terminal 420 is exposed from the surface 411. The circuit connection portion 421 includes a portion that bends in the vicinity of the surface 411 and extends obliquely in a direction away from the surface 411. The circuit connecting portion 421 includes a vertically extending portion connected to the upper end of the obliquely extending portion. As a result, the end portion of the circuit connection portion 421 is shifted in the x-axis direction with respect to the position of the relay terminal 420 on the surface 411.

  As shown in FIG. 7B, among the plurality of relay terminals 420 provided in the inspection jig 400, one of the adjacent relay terminals 420 is arranged in a state of being rotated 180 degrees around the z axis with respect to the other. As a result, the circuit connecting portions 421 of the adjacent relay terminals 420 are bent to the opposite side with respect to the arrangement direction of the plurality of relay terminals 420. Accordingly, the circuit connection portions 421 are staggered in a plan view.

  When the product to be inspected is downsized, the interval between the relay terminals is reduced. In this case, it may be difficult to connect the relay terminal and the wiring. On the other hand, in the present embodiment, the circuit connection portion 421 to which the wiring is connected has a staggered arrangement. For this reason, it becomes possible to provide the space | interval of the circuit connection part 421 widely. Accordingly, the wiring work can be facilitated.

  In the present embodiment, the relay terminal 420 includes two bent portions. On the other hand, as long as the circuit connection part 421 of the adjacent relay terminal 420 is bent to the opposite side to the arrangement direction of the relay terminals 420, the circuit connection part 421 may have another shape. For example, the circuit connection portion 421 may include one bent portion.

Embodiment 5. FIG.
FIG. 8 is a cross-sectional view of an inspection jig according to Embodiment 5 of the present invention. The inspection jig 500 according to the present embodiment includes a relay adapter 510. In the relay adapter 510, a cavity 515 penetrating from the front surface 511 to the back surface 519 is formed. The connection portion 522 according to the present embodiment is a metal layer 546 formed on the side wall 513 of the relay adapter 510 formed by the cavity 515. In addition, the inspection jig 500 includes the contact 30.

  In the present embodiment, the connection portion 522 and the contact 30 are connected by pressing the elastic portion 31 into the connection portion 522. In a state where the connection part 522 and the contact 30 are connected, the elastic part 31 exerts an elastic force on the connection part 522. In a state where the elastic part 31 and the connection part 522 are connected, the connection part 522 reduces the distance between the two metal pieces provided in the elastic part 31. For this reason, the elastic force acts in the direction in which the two metal pieces provided in the fork-shaped elastic part 31 open. The interval in the x-axis direction of the connecting portion 522 is adjusted so that the connecting portion 522 and the contact 30 can be connected by the elastic force generated by the elastic portion 31.

  Also in the present embodiment, the contact 30 can be replaced by inserting and removing the contact 30 from the back surface 519 side. For this reason, exchange of the contact 30 becomes easy. Further, in the present embodiment, the elastic part 31 is sandwiched between the connection parts 522 from both sides. For this reason, the contact area of the connection part 522 and the contact 30 can be enlarged. Therefore, the contact resistance can be reduced.

  In the present embodiment, the exposed portion 521 which is a portion exposed on the surface 511 of the metal layer 546 may be a circuit connection portion. In this case, wiring is connected to the exposed portion 521. Alternatively, the circuit connection portion may be formed by attaching a metal member to the connection portion 522 from the surface 511 side.

100, 200, 300, 400, 500, 800 Inspection jig, 11, 211, 411, 511 Front surface, 19, 219, 519 Back surface, 15, 515 Cavity, 10, 210, 410, 510 Relay adapter, 21, 421 , 821 Circuit connection part, 22, 222, 522, 822 Connection part, 20, 220, 420, 820 Relay terminal, 30, 230, 830 Contactor 31, 231, 331, 334, 337, 831 Elastic part, 546 Metal Layer, 320 first relay terminal, 327 second relay terminal, 330 first contact, 333 second contact, 12 circuit board, 16 circuit pattern, 18 passive component

Claims (14)

A relay adapter comprising a front surface, a back surface, and a cavity penetrating from the front surface to the back surface;
A relay terminal that is attached to the relay adapter and includes a circuit connection portion disposed on the surface side and a connection portion provided in the cavity,
A contact provided so that it can be inserted and removed from the back side;
With
One of the connection part and the contact has an elastic part,
The inspection jig, wherein the elastic portion exerts an elastic force on the other of the connecting portion and the contact so that the connecting portion and the contact are connected. The elastic portion is provided on the contact,
The inspection jig according to claim 1, wherein the contactor sandwiches the connection portion from both sides. The elastic part is provided in the connection part,
The inspection jig according to claim 1, wherein the connection portion has a shape that sandwiches the contact from both sides. The connection part is a metal layer formed on a side wall of the relay adapter formed by the cavity;
The inspection jig according to claim 1, wherein the elastic portion is provided on the contact.   The length of the connecting portion in a first direction that is parallel to the surface and perpendicular to the direction in which the elastic portion exerts an elastic force is greater than the length of the contact in the first direction. The inspection jig according to any one of 2 to 4. A plurality of the contacts;
The inspection jig according to claim 5, wherein the plurality of contacts overlap in the first direction. The relay terminal includes a first relay terminal and a second relay terminal,
The contact includes a first contact and a second contact,
The second relay terminal is arranged to be shifted from the first relay terminal in a direction in which the elastic portion exerts an elastic force,
The first contact is connected to the first relay terminal;
The second contact is connected to the second relay terminal;
The inspection jig according to claim 5, wherein the first contact and the second contact are arranged to overlap in the first direction at a contact portion with an inspection target. A plurality of the relay terminals,
The inspection jig according to claim 1, wherein the circuit connection portions of the plurality of relay terminals are arranged in a zigzag arrangement in a plan view. The plurality of relay terminals are arranged linearly on the surface,
The inspection jig according to claim 8, wherein a staggered arrangement is formed by bending circuit connection portions of the plurality of relay terminals.   The inspection relay according to claim 1, wherein the relay adapter includes a circuit board on the surface.   The inspection jig according to claim 10, wherein the circuit board includes a circuit pattern.   The inspection relay according to claim 1, wherein the relay adapter includes a passive component on the surface.   The inspection relay according to claim 1, wherein the relay adapter includes polyacetal.   The inspection jig according to claim 1, wherein the relay adapter includes a baking material.

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