Probe and socket

Abstract

Provided are a probe and a socket with which tip position accuracy of the probe can be improved. Provided is a probe having a plunger inserted into a probe hole of a housing, the outer diameter of a part or the whole of the outer periphery of the plunger coinciding with the inner diameter of the probe hole or being larger than the inner diameter, and a slit that enables the outer diameter to be elastically reduced being formed in the plunger.

Description

Probes and Sockets

[0001] The present invention relates to a probe and a socket.

[0002] 1 and 2 show an example of a probe generally called a pogo pin. In this case, a probe 1D is inserted into a probe hole 52 (hereinafter referred to as a "probe hole") formed in a housing 51 of a socket 5D in order to hold the probe 1D, and the inner diameter of the probe hole 52 is set larger than the outer diameter of the probe 1D so that the probe 1D can slide within the probe hole 52. As a result, the probe 1D tilts in the probe hole 52 by the amount of the gap between the probe hole 52 and the outer diameter of the probe 1D, and the positional accuracy of the tip of the probe 1D deteriorates.

[0003] Furthermore, although the following Patent Document 1 has been proposed, a gap remains between the probe and the probe hole, which results in a certain degree of displacement of the probe relative to the probe hole.

[0004] Japanese Patent Application Laid-Open No. 2006-23177

[0005] In the prior art, the probe tilts in the probe hole by the amount of the gap between the inner diameter of the probe hole on the housing side and the outer diameter of the probe, which causes a problem of poor probe tip position accuracy.

[0006] An example of an object of the present invention is to provide a probe and a socket that improve the positional accuracy of the tip of the probe. Other objects of the present invention will become apparent from the description of this specification.

[0007] One aspect of the present invention is a probe having a plunger inserted into a probe hole in a housing, wherein the outer diameter of part or the entire outer periphery of the plunger matches the inner diameter of the probe hole or is larger than the inner diameter, and the plunger is formed with a slit that allows the outer diameter to be elastically reduced.

[0008] One aspect of the present invention is a socket comprising the probe and the housing having the probe hole, wherein the plunger of the probe is inserted into the probe hole with the outer diameter thereof matching the inner diameter of the probe hole or with the outer diameter elastically contracted.

[0009] According to the above aspect of the present invention, it is possible to improve the positional accuracy of the tip of the probe.

[0010] FIG. 1 is a front view of a conventional probe 1D and socket 5D. FIG. 2 is an enlarged plan view of a conventional probe 1D and socket 5D. FIG. 3 is a front cross-sectional view of a probe 1 and socket 5 according to a first embodiment of the present invention. FIG. 4 is a front view of the probe 1 and socket 5. FIG. 5 is an enlarged plan view of the probe 1 and socket 5, with the internal structure omitted. FIG. 6 is a front view of a probe 1A and socket 5A according to a second embodiment of the present invention. FIG. 7 is an enlarged plan view of a probe 1B and socket 5B according to a third embodiment of the present invention, with the internal structure omitted. FIG. 8 is a front view of a probe 1C and socket 5C according to a fourth embodiment of the present invention. FIG. 9 is an enlarged plan view of the probe 1C and socket 5C, with the internal structure omitted.

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Similar components will be designated by similar reference numerals, and descriptions thereof will be omitted where appropriate. Furthermore, in this specification, ordinal numbers such as "first," "second," and "third" are used merely to distinguish between components with similar names, unless otherwise specified, and do not refer to specific characteristics of the components (for example, order or importance).

[0012] 3 to 5, a probe 1 according to a first embodiment of the present invention and a socket 5 including the probe 1 will be described. As shown in these figures, the probe 1 has a first plunger 10 having a slit 11, a second plunger 20 part of which slides inside the first plunger 10, and a spring 30 disposed within the first plunger 10. The front and rear directions of the probe 1 are defined in FIG. 3.

[0013] The socket 5 includes a probe 1 and a housing 40 having a probe hole 43 into which the probe 1 is inserted and disposed. For the sake of convenience of explanation, one probe 1 and one probe hole 43 are shown in Figures 3 to 5, but the housing 40 normally has a plurality of probe holes 43, and a probe 1 is inserted into each of the probe holes 43.

[0014] The first plunger 10 is a distal plunger made of a flexible conductive metal such as a copper alloy, e.g., phosphor bronze or beryllium copper. The first plunger 10 is cylindrical and has a plurality of longitudinal slits 11 parallel to its central axis, each extending to the distal end of the first plunger 10. In the example shown in FIG. 5 , a pair of slits 11 are formed at positions approximately point-symmetric with respect to the central axis of the first plunger 10. By providing the slits 11 on the distal end of the first plunger 10, the outer diameter of the first plunger 10 at the portion where the slits 11 are provided can be elastically reduced (reduced). The distal end 12 of the first plunger 10 as a distal plunger is the portion that contacts an electrode, such as a bump, of the device under test, and has, for example, a mountain-like shape with a pointed portion.

[0015] The first plunger 10 has a protrusion 13 on part of its outer periphery, which runs around the periphery and is divided by a slit 11. The protrusion 13 is located on the tip side of the longitudinal midpoint of the first plunger 10, and the tip and rear ends of a peripheral surface 13a of the protrusion 13 (the upper surface of the protrusion 13, which extends in a direction around the periphery of the first plunger 10) form tapered surfaces 13b so as not to impair slidability with respect to the probe hole 43. Before insertion into the socket 5, the outer diameter of the first plunger 10 at the position where the protrusion 13 is formed (the diameter of the outer periphery passing through the peripheral surface 13a of the protrusion 13) is set to be equal to or slightly larger than the inner diameter of the probe hole 43. The formation of the longitudinal slit 11 allows the outer diameter to be elastically reduced.

[0016] A flange 15 is formed at the rear end of the first plunger 10 to prevent it from coming off the housing 40. The first plunger 10 is cylindrical with a slit 11 added, and a hollow portion 16 on its inner periphery accommodates a part of the second plunger 20 and the spring 30. A locking portion 17 for preventing the spring 30 from coming off is formed at the tip end of the hollow portion 16 so as to protrude inward.

[0017] The second plunger 20 is a rear end plunger made of a conductive metal such as a copper alloy, and has a cylindrical inlet tube 21 with a diameter larger than the diameter of the rear end opening of the first plunger 10, an intermediate columnar portion 22 with a smaller diameter than the inlet tube 21 extending rearward from the inlet tube 21, and an even smaller diameter rear end columnar portion 23. The inlet tube 21 is slidable along the inner circumferential surface of the hollow portion 16 of the first plunger 10. The tip of the rear end columnar portion 23 (the rear end of the probe 1) is the portion that comes into contact with an electrode of a testing board (not shown) that is arranged on the rear end side of the housing 40 of the socket 5.

[0018] The spring 30 is a coil spring made of elastic metal, and is inserted and positioned in the hollow portion 16 together with the inlet tube portion 21 of the second plunger 20 before the rear end opening of the first plunger 10 is machined to a smaller diameter, and then the rear end opening of the first plunger 10 is machined (for example, by crimping) to a smaller diameter as shown in Figures 3 and 4. The tip of the spring 30 is locked by the retaining locking portion 17 of the first plunger 10, and the rear end abuts against the end face of the inlet tube portion 21, thereby urging the first plunger 10 and the second plunger 20 in a direction separating them.

[0019] The housing 40 of the socket 5 has a first housing portion 41 and a second housing portion 42, both of which are made of an inelastic, rigid, insulating hard material. The probe hole 43 of the housing 40 is a continuous through-hole consisting of a hole portion 43a formed in the first housing portion 41 on the tip side and a hole portion 43b formed in the second housing portion 42 on the rear side. The hole portion 43a has a constant inner diameter and determines the position of the tip of the probe 1 inserted and placed therein, i.e., the position of the tip of the first plunger 10. The hole portion 43b has a large-diameter portion 43c on the tip side that is larger in diameter than the hole portion 43a and larger in diameter than the flange portion 15 of the first plunger 10, and a small-diameter portion 43d on the rear side that slidably supports the rear end columnar portion 23 of the second plunger 20. In the probe hole 43, the flange portion 15 of the first plunger 10 abuts against a step surface 45 formed by the difference in diameter between the hole portion 43a and the large diameter portion 43c of the hole portion 43b, thereby preventing the probe 1 from slipping out toward the tip.

[0020] The socket 5 is assembled, for example, by the following procedure. With the first housing portion 41 and the second housing portion 42 separated, the probe 1 is inserted from the tip side into the hole portion 43a, which is the tip side portion of the probe hole 43 in the first housing portion 41. At this time, the outer diameter of the first plunger 10 at the position where the convex portion 13 is formed is reduced by a radial external force, thereby facilitating insertion into the hole portion 43a. Then, the tip side of the flange portion 15 of the first plunger 10 is inserted and positioned inside the hole portion 43a, and the first housing portion 41 and the second housing portion 42 are then stacked and integrated as shown in FIGS. 3 and 4 . At this time, the rear end columnar portion 23 of the second plunger 20 passes through the small diameter portion 43d of the hole portion 43b.

[0021] In the socket 5, when the first plunger 10 is cylindrical with a pair of longitudinal slits 11 formed at positions approximately point-symmetrical with respect to its central axis and the probe hole 43 is a circular hole, the first plunger 10 is inscribed almost evenly in the hole portion 43a of the probe hole 43 at the position where the convex portion 13 is formed, or is inscribed at least in two positions approximately 180 degrees apart in the circumferential direction. Therefore, it is possible to eliminate rattle caused by the gap between the probe hole 43 and the first plunger 10 and to substantially eliminate tilt of the probe 1 with respect to the probe hole 43, thereby improving the positional accuracy of the tip of the probe 1. In other words, the center of the probe hole 43 and the central axis of the probe can be aligned with high precision.

[0022] When a testing board (not shown) is attached to the bottom side of the second housing portion 42 of the socket 5, the rear columnar portion 23 is pushed back by the testing board from a state in which it protrudes from the second housing portion 42, and the tip of the rear columnar portion 23 contacts the electrode of the testing board at a predetermined pressure due to the elastic force of the compressed spring 30. Also, in a measurement state in which a device under test (not shown) is placed on the socket 5, the tip 12 of the first plunger 10 of the probe 1 comes into contact with the electrode of the device under test and is pressed down, and the elastic force of the compressed spring 30 causes the tip 12 to contact the electrode of the device under test at a predetermined pressure.

[0023] According to this embodiment, the following effects can be achieved.

[0024] (1) The first plunger 10 serving as the tip-side plunger has an outer diameter at a position where a protrusion 13, which is a part of its outer periphery, is formed, which is equal to or slightly larger than the inner diameter of the hole 43 a of the probe hole 43 of the socket 5, and is configured to have a longitudinal slit 11 formed in the first plunger 10 that allows the outer diameter to be elastically reduced. Therefore, the first plunger 10 is inscribed in the hole 43 a of the probe hole 43 almost evenly or inscribed in at least two places, thereby absorbing variations in the outer diameter of the first plunger 10 relative to the inner diameter of the hole 43 a of the probe hole 43. As a result, rattle caused by a gap between the probe hole 43 and the first plunger 10 is eliminated, and tilt of the probe 1 relative to the probe hole 43 is substantially eliminated, thereby improving the tip position accuracy of the probe 1.

[0025] (2) Since a pair of slits 11 are formed at positions approximately point-symmetrical with respect to the central axis of the first plunger 10, the first plunger 10 is inscribed in the inner circumferential surface of the hole portion 43a of the probe hole 43 at least at two locations approximately 180 degrees apart in the circumferential direction. This makes it possible to further improve the positional accuracy of the tip of the probe 1.

[0026] (3) The first plunger 10 has a protrusion 13 on part of its outer periphery, and the protrusion 13 goes around the outer periphery and is divided by the longitudinal slits 11, so that the peripheral surface 13a of the protrusion 13 can come into contact with and slide against the hole 43a of the probe hole 43. Since the sliding area of ​​the first plunger 10 relative to the hole 43a is reduced, the slidability of the first plunger 10 relative to the housing 40 is improved. In addition, the leading and trailing end sides of the protrusion 13 have tapered surfaces 13b, so that the first plunger 10 can slide smoothly.

[0027] (4) The test tool is provided with the first plunger 10 as the leading-end plunger, the second plunger 20 as the trailing-end plunger that is freely slidable relative to the first plunger 10, and the spring 30 that biases the first plunger 10 and the second plunger 20 in the direction of separating them. Therefore, the elastic force of the spring 30 can be utilized to generate the required contact pressure on the electrodes of the device under test and the testing board.

[0028] (5) The first plunger 10 is cylindrical with a slit 11 added thereto and has a hollow portion 16 in which the inlet tube portion 21 of the second plunger 20 and the spring 30 are accommodated, so that the addition of the slit 11 does not increase the length of the probe 1.

[0029] (6) In the socket 5, the first plunger 10 has an outer diameter that matches the inner diameter of the hole 43a of the probe hole 43 in the housing 40, or is inserted into the hole 43a with the outer diameter elastically contracted, so that the first plunger 10 comes into contact with the inner surface of the hole 43a with a predetermined contact pressure. Therefore, it is possible to eliminate rattle of the probe 1 in the hole 43a and substantially eliminate tilt of the probe 1 in the hole 43a, thereby realizing a socket 5 with high probe positioning accuracy.

[0030] 6 shows a probe 1A according to a second embodiment of the present invention and a socket 5A including the probe 1A. In this case, the probe 1A has a configuration in which the flange portion 15 in the probe 1 of the first embodiment is omitted, and the outer diameters of the first plunger 10A and the second plunger 20 are equal to or smaller than the outer diameter of the first plunger 10A at the portion where the convex portion 13 is located. The other configurations are the same as those of the probe 1. The housing 40 of the socket 5A is the same as that of the first embodiment.

[0031] According to the second embodiment shown in FIG. 6 , even if the flange portion that prevents the probe 1A from coming off the housing 40 is omitted, the contact pressure between the first plunger 10A of the probe 1A and the hole portion 43a of the probe hole 43 can be appropriately set. In other words, by bringing the probe 1A into inward contact with the hole portion 43a with a force equal to or greater than a certain level that does not interfere with the sliding of the probe 1A, the probe 1A can be prevented from easily coming off the housing 40, thereby realizing the function of preventing the probe 1A from coming off. Furthermore, because there is no flange portion, the probe 1A can be inserted into the probe hole 43 of the housing 40 from the distal end side without separating the first housing portion 41 and the second housing portion 42 that make up the housing 40. Furthermore, the probe 1A can be pulled out of the housing 40 from the distal end side, facilitating replacement of the probe 1A. Other advantages and functions are the same as those of the first embodiment.

[0032] 7 shows a probe 1B and a socket 5B including the same according to a third embodiment of the present invention. In this case, the first plunger 10 in the probe 1 of the first embodiment has a pair of slits 11, whereas the first plunger 10B of the probe 1B has two pairs of slits 11 at positions that are approximately point-symmetrical with respect to the central axis. The other configurations are the same as those of the probe 1. The housing 40 of the socket 5B is the same as that of the first embodiment.

[0033] According to the third embodiment shown in Fig. 7, two pairs of slits 11 are formed at positions approximately point-symmetrical with respect to the central axis of the first plunger 10B, so that the first plunger 10B is inscribed in the inner peripheral surface of the hole portion 43a of the probe hole 43 at least four locations approximately 90 degrees apart in the circumferential direction. This makes it possible to further improve the positional accuracy of the tip of the probe 1B. Other effects are the same as those of the first embodiment.

[0034] 8 and 9 show a probe 1C and a socket 5C including the probe 1C according to a fourth embodiment of the present invention. In the probe 1 of the first embodiment described above, the convex portion 13 formed on the first plunger 10 encircles the outer periphery and is divided by slits 11. However, this convex portion does not have to encircle the outer periphery. In the fourth embodiment, the first plunger 10C has a plurality of discontinuous, small-area convex portions 13A (e.g., hemispherical, etc.) instead of the encircling convex portion. The convex portions 13A are preferably arranged in positions approximately point-symmetrical with respect to the central axis of the first plunger 10C, and the portion where the convex portion 13A is located is inscribed in the hole portion 43a of the probe hole 40. The other configurations are the same as those of the probe 1. The housing 40 of the socket 5C is the same as that of the first embodiment.

[0035] 8 and 9, the discontinuous, small-area protrusions 13A may be formed or machined on the outer periphery of the first plunger 10C, which may facilitate the formation or machining. Other advantages are the same as those of the first embodiment.

[0036] Although the embodiments of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various other configurations can also be adopted.

[0037] In the first to third embodiments, the probe hole of the housing is exemplified as a round hole, which is easy to mold or process, but it may have other shapes, for example, a polygonal hole. Furthermore, while the tip side of the tip plunger is cylindrical with slits, it may have a shape other than a cylinder, for example, a polygonal tube with slits, as long as it can be inscribed evenly (for example, at multiple locations) on the inner surface of the probe hole. The tip plunger does not need to be hollow from the tip to the rear end; it only needs to have a hollow portion to accommodate at least a portion of the rear plunger and the spring.

[0038] According to the present specification, there are provided a probe and a socket having the following aspects.

[0039] (Mode 1) A probe having a plunger inserted into a probe hole in a housing, wherein the outer diameter of a part or the entire outer circumference of the plunger is the same as or larger than the inner diameter of the probe hole, and the plunger is formed with a slit that allows the outer diameter to be elastically reduced.

[0040] According to the above-mentioned aspect 1, the tip side plunger is inscribed almost evenly in the probe hole, which can absorb variations in the outer diameter of the plunger and the inner diameter of the probe hole, and it is possible to eliminate rattle caused by the gap between the probe hole and the plunger and to substantially eliminate tilt of the probe relative to the probe hole, thereby improving the positional accuracy of the probe tip.

[0041] (Aspect 2) A probe in which the slits are formed in one or more pairs at positions approximately point-symmetric with respect to the central axis of the plunger.

[0042] According to the above-mentioned aspect 2, the plunger is inscribed in the inner surface of the probe hole at a plurality of points that are at least approximately point-symmetric in the circumferential direction, which makes it possible to further improve the positional accuracy of the probe tip.

[0043] (Aspect 3) A probe, wherein the plunger has a convex portion on a part of its outer periphery, and the portion where the convex portion is located is inscribed in the probe hole.

[0044] According to the third aspect, the plunger can slide in contact with the probe hole at the portion where the protrusion is formed. The sliding area of ​​the plunger relative to the probe hole is reduced, improving the slidability of the plunger relative to the housing.

[0045] (Aspect 4) A probe, wherein the protrusion surrounds the outer periphery and is divided by the longitudinal slit.

[0046] According to the above-mentioned fourth aspect, the convex portion goes around the outer periphery except for the position where the slit is formed, so that the position of the tip side plunger relative to the probe hole is stable.

[0047] (Aspect 5) A probe, wherein the tip and rear end sides of the convex portion are tapered surfaces.

[0048] According to the above-mentioned aspect 5, the front end side and rear end side of the convex portion 13 are tapered surfaces, so that the front end side plunger can slide smoothly.

[0049] (Aspect 6) A probe including a rear end plunger slidable relative to the front end plunger, which is the plunger, and a spring that biases the front end plunger and the rear end plunger in a direction separating them from each other.

[0050] According to the above-mentioned sixth aspect, the probe can generate a required contact pressure to the electrodes of the device under test and the test board by utilizing the elastic force of the spring.

[0051] (Aspect 7) A probe, wherein the outer diameters of the front end plunger and the rear end plunger are equal to or smaller than the outer diameter of the front end plunger at a portion where the convex portion is located.

[0052] According to the seventh aspect described above, even if the flange portion that prevents the probe from coming off the housing is omitted, the contact pressure between the distal plunger of the probe and the probe hole can be appropriately set to prevent the probe from easily coming off the housing, thereby realizing the probe's function of preventing it from coming off. Furthermore, since there is no flange portion, the probe can be inserted into the probe hole from the distal end side of the probe hole in the housing and placed therein. In addition, the probe can be pulled out of the housing from the distal end side, making it easy to replace the probe.

[0053] (Aspect 8) The probe, wherein the tip-end plunger is cylindrical with the slit added thereto and has a hollow portion in which at least a portion of the rear-end plunger and the spring are housed.

[0054] According to the above-mentioned eighth aspect, the tip plunger has a hollow portion in which a part of the rear plunger and the spring are housed, so that the length of the probe does not increase due to the addition of the slit.

[0055] (Aspect 9) A socket comprising: the probe; and the housing having the probe hole, wherein the plunger of the probe is inserted into the probe hole with the outer diameter thereof matching the inner diameter of the probe hole or with the outer diameter thereof elastically contracted.

[0056] According to the above-mentioned Aspect 9, the plunger can contact the inner surface of the probe hole without rattle. Therefore, rattle of the probe in the probe hole can be eliminated and tilt of the probe in the probe hole can be substantially eliminated, thereby realizing a socket with high probe positioning accuracy.

[0057] 1, 1A, 1B, 1C, 1D Probe, 5, 5A, 5B, 5C, 5D Socket, 10, 10A, 10B, 10C First plunger, 11 Slit, 12 Tip portion, 13, 13A Convex portion, 13a Circumferential surface, 13b Tapered surface, 15 Flange portion, 16 Hollow portion, 17 Anti-detachment locking portion, 20 Second plunger, 21 Inlet tube portion, 22 Intermediate columnar portion, 23 Rear end columnar portion, 30 Spring, 40, 51 Housing, 41 First housing portion, 42 Second housing portion, 43, 52 Probe hole, 43a, 43b Hole portion, 43c Large diameter portion, 43d Small diameter portion, 45 Step surface

Claims

A probe having a plunger inserted into a probe hole in a housing, The outer diameter of a part of or the entire outer periphery of the plunger is equal to or larger than the inner diameter of the probe hole, The plunger has a slit formed therein that allows the outer diameter to be elastically reduced. 　 The probe according to claim 1 , wherein the slits are formed in one or more pairs at positions substantially point-symmetric with respect to a central axis of the plunger. 　 The probe according to claim 1 or 2, wherein the plunger has a convex portion on a part of its outer periphery, and the portion where the convex portion is located is inscribed in the probe hole. 　 The probe according to claim 3 , wherein the protrusions are arranged around the outer periphery and are divided by the longitudinal slits. 　 The probe according to claim 4 , wherein the front and rear ends of the convex portion are tapered.

3. The probe according to claim 1, further comprising: a rear end plunger slidable relative to the front end plunger; and a spring biasing the front end plunger and the rear end plunger in a direction separating them from each other. 　 The probe according to claim 6 , wherein the outer diameters of the front end plunger and the rear end plunger are equal to or smaller than the outer diameter of the front end plunger at a portion where the convex portion is located. 　 The probe according to claim 6 , wherein the distal plunger is cylindrical with the slit added thereto and has a hollow portion in which at least a portion of the proximal plunger and the spring are housed. 　 The probe according to claim 1 or 2; the housing having the probe hole; A socket in which the plunger of the probe is inserted into the probe hole with the outer diameter thereof coinciding with the inner diameter of the probe hole or with the outer diameter thereof elastically contracted.

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