probe

Abstract

To reliably generate an internal side pressure of a plunger to stabilize a resistance value.SOLUTION: A probe comprises: a first plunger having a hollow barrel portion; a second plunger that slides freely in the barrel portion and protrudes from an open end of the barrel portion; and a spring that is provided inside the barrel portion and urges the first plunger and the second plunger in directions away from each other. The second plunger has a hollow portion that accommodates a part of the spring. The spring has a loosely wound portion, a first tightly wound portion located at one end side of the loosely wound portion and in contact with the first plunger, and a second tightly wound portion located at the other end side of the loosely wound portion and in contact with the second plunger. The first tightly wound portion and the second tightly wound portion have a diameter different from that of the loosely wound portion. Central axes of the first tightly wound portion and the second tightly wound portion are offset in a same direction with respect to a central axis of the loosely wound portion.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD

[0001] The present invention relates to a probe. BACKGROUND ART

[0002] Conventionally, as a probe, a structure is known that includes a conductive first plunger having a hollow barrel portion, a conductive second plunger that is slidable inside the barrel portion and protrudes from the open end of the barrel portion, and a spring that biases the first plunger and the second plunger in directions away from each other.

[0003] However, since conventional general springs do not have an eccentric structure, they are less likely to deflect even when compressed in the case of a probe. For this reason, it is difficult to generate a lateral pressure in the direction of pressing the second plunger against the inner wall of the barrel portion, and the resistance value of the probe, that is, the resistance value between the first plunger and the second plunger, is not stabilized.

[0004] Further, Patent Document 1 below discloses a probe pin in which the portion of the pin that contacts the spring (hereinafter referred to as the pin bottom surface) is machined into a conical shape, and the spring is installed in the space formed by the pin and the hole of the tube. In this case, the spring has a central portion with substantially equal diameters, and a tapered portion adjacent thereto that gradually decreases in diameter and whose central axis is offset obliquely from the central axis of the central portion, and is characterized by a generally curved shape. When both ends of the spring are compressed by the conical portion of the pin bottom surface and the bottom surface of the tube hole during use, the pin receives a load in a direction inclined from the axial direction of the tube due to the tapered portion of the spring, so the pin is in an inclined state, and the pin is pressed against the inner wall of the tube to generate a lateral pressure corresponding to the amount of axial compression of the spring. However, the structure of the spring is complicated and may require much labor for manufacturing. PRIOR ART DOCUMENTS PATENT DOCUMENTS

[0005] [Patent Document 1] Patent No. 5197754 [Overview of the project] [Problems that the invention aims to solve]

[0006] As described above, a probe with a spring structure that does not have a typical eccentric structure cannot generate stable lateral pressure, resulting in unstable probe resistance. Furthermore, the probe pin described in Patent Document 1 is difficult to apply when the spring structure is complex.

[0007] The present invention has been made in recognition of these circumstances, and one of its objectives is to provide a probe that stabilizes the resistance value by reliably generating internal lateral pressure in the plunger with a simple spring structure. Other objectives of the present invention will become apparent from the description herein. [Means for solving the problem]

[0008] One aspect of the present invention is a probe comprising a conductive first plunger having a hollow barrel portion, A conductive second plunger is slidably located within the barrel portion and protrudes from the open end of the barrel portion, The barrel portion is provided with a spring that biases the first plunger and the second plunger toward each other, The spring has a loosely wound portion, a first seated portion located at one end of the loosely wound portion and in contact with the first plunger, and a second seated portion located at the other end of the loosely wound portion and in contact with the second plunger, wherein the first seated portion and the second seated portion have different diameters from the loosely wound portion. The central axes of the first and second winding sections are offset in the same direction with respect to the central axis of the loosely wound section.

[0009] According to the above embodiment of the present invention, a probe can be realized that reliably generates internal lateral pressure in the plunger with a simple spring structure, thereby stabilizing the resistance value. [Brief explanation of the drawing]

[0010] [Figure 1] This is a longitudinal cross-sectional view showing an embodiment of the probe according to the present invention. [Figure 2] This is a front view of the spring used in the embodiment. [Figure 3] This is a left side view of the same object. [Figure 4] This is a right side view of the same object. [Figure 5] This is an explanatory diagram showing an example of how to use the probe shown in the embodiment. [Modes for carrying out the invention]

[0011] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. The same or equivalent components, members, processes, etc., shown in each drawing are denoted by the same reference numerals, and redundant descriptions are omitted where appropriate. Furthermore, the embodiments are illustrative and not limiting to the invention, and not all features or combinations thereof described in the embodiments are necessarily essential to the invention.

[0012] Embodiments of the probe according to the present invention will be described with reference to Figures 1 to 4. In these figures, the probe 1 comprises a conductive first plunger 10 integrally with a barrel portion 11, a conductive second plunger 20 that is slidable within the barrel portion 11 and protrudes from the open end of the barrel portion 11, and a spring 30 provided inside the barrel portion 11 that biases the first plunger 10 and the second plunger 20 toward each other.

[0013] The barrel portion 11 of the first plunger 10 is a bottomed cylindrical shape with a cylindrical hollow portion 12 on the inside, and one end is open. The opposite end of the first plunger 10 to the opening is a tip portion 13 that contacts the bump or electrode of the object to be inspected, such as a semiconductor, and the tip portion 13 has, for example, a plurality of pointed protrusions 14.

[0014] The second plunger 20 has a bottomed cylindrical shape with a cylindrical hollow section 21 into which a part of the spring 30 is inserted. The second plunger 20 has an entry tube section 22 that is slidable inside the barrel section 11, and a tip section 23 that is smaller in diameter than the entry tube section 22 and protrudes from the end of the barrel section 11. The tip section 23 is provided with a projection 24 that contacts the electrodes of the inspection substrate. The entry tube section 22 is held in place by a crimped section 15 at the open end of the barrel section 10 so as not to come off.

[0015] Figure 2 is a front view of the spring 30 when there is no external force, Figure 3 is a left side view, and Figure 4 is a right side view. As shown in these figures, the spring 30 is a conductive coil spring made by winding an elastic metal wire, and has a loosely wound portion 31 wound to have a constant outer diameter, a first seated wound portion 32 located on one end of the loosely wound portion 31 and in contact with the inner bottom surface of the first plunger 10, and a second seated wound portion 33 located on the other end of the loosely wound portion 31 and in contact with the inner bottom surface of the second plunger 20. The loosely wound portion 31 is an effective wound portion that functions as a compression spring, and is, for example, tightly wound. The first seated wound portion 32 and the second seated wound portion 33 have different diameters from the loosely wound portion 31. In the illustrated case, the first and second winding sections 32 and 33 have larger diameters than the loosely wound section 31. As can be seen from Figures 3 and 4, the central axis a of the first winding section 32 and the central axis b of the second winding section 33 are offset (eccentric) in the same direction with respect to the central axis c of the loosely wound section 31. Furthermore, the outer circumferential ends of the loosely wound section 31 and the outer circumferential ends of the first and second winding sections 32 and 33 are aligned on the outer side opposite to the offset direction with respect to the central axis c of the loosely wound section 31.

[0016] As shown in Figure 1, a recess 16 is formed on the inner bottom surface of the barrel portion 11, into which the first seat coil portion 32 of the spring 30 fits. To ensure a good seating of the first seat coil portion 32, the bottom surface 16a of the recess 16 into which the first seat coil portion 32 abuts is formed into a flat surface perpendicular to the central axis 11a of the barrel portion 11, for example, by end milling. Note that a flat surface cannot be achieved by ordinary drilling.

[0017] In the configuration of the above embodiment, when a load is applied to the probe 1 from the unloaded state in FIG. 1 to push the distal end portion 23 of the second plunger 20 inward, the spring 30 is compressed. At this time, due to the fact that the first end coil portion 32 and the second end coil portion 33 are formed at positions eccentric to the loosely wound portion 41, the spring 30 bends in an arch shape, in other words, a bow shape. As a result, the inner wall of the second plunger 20 is pushed by the spring 30, generating a lateral pressure in the direction of pressing the tube insertion portion 22 of the second plunger 20 against the inner wall of the barrel portion 11. This lateral pressure causes the tube insertion portion 22 of the second plunger 20 to stably contact the inner wall of the barrel portion 11, and the contact resistance value between the first plunger 10 and the second plunger 20 can be stably maintained at a low value.

[0018] FIG. 5 is an explanatory diagram showing a usage example of the probe 1 shown in the embodiment. In this case, the probe 1 is incorporated into a socket 90 having an insulating support 100. The insulating support 100 has a structure in which a first insulating support 101 having a through hole 101a and a second insulating support 102 having a through hole 102a are stacked, and the probe 1 is held in the through hole 101a and the through hole 102a so as not to fall off.

[0019] When inspecting an inspection object 110 such as a semiconductor using the socket 90, the inspection object 110 is pushed down to bring the protrusion 14 of the first plunger 10 into contact with the bump 111 of the inspection object 110, and the protrusion 24 provided at the distal end portion 23 of the second plunger 20 is brought into abutment with the electrode 121 of the inspection substrate 120. Thereby, the bump 111 of the inspection object 110 and the inspection substrate 120 are electrically connected via the probe 1.

[0020] According to the present embodiment, the following effects can be achieved.

[0021] (1) The first and second end turns 32, 33 of the spring 30 that biases the first plunger 10 and the second plunger 20 in directions away from each other have a diameter different from that of the loosely wound portion 41, and the central axes of the first and second end turns 32, 33 are offset (eccentric) in the same direction relative to the central axis of the loosely wound portion 31. For this reason, the spring 30 is easily deflected into an arch shape. As a result, the inner wall of the second plunger 20 is pushed by the spring 30, the inlet pipe portion 22 of the second plunger 20 stably contacts the inner wall of the barrel portion 11, and the contact resistance value between the first plunger 10 and the second plunger 20 can be stably maintained at a low value.

[0022] (2) When the first end turn 32 and the second end turn 33 of the spring 30 are made larger in diameter than the loosely wound portion 31, the first and second end turns 32, 33 can be easily formed even when the spring 30 is made small in diameter. In addition, the spring 30 abuts against the inner bottom surface of the first plunger 10 with a large diameter, so that the retention of the end portion of the spring 30 is stabilized.

[0023] (3) The recess 16 into which the first end turn 32 is fitted is formed on the inner bottom surface of the barrel portion 11, and the bottom surface 16a of the recess 16 against which the first end turn 32 abuts is a flat surface perpendicular to the central axis 11a of the barrel portion 11, so that the seating of the first end turn 32 relative to the inner bottom surface of the first plunger 10 is stabilized.

[0024] (4) The spring 30 having the loosely wound portion 31 and the first and second end turns 32, 33 on both sides thereof has a bilaterally symmetric shape, and exhibits the same performance even when turned upside down, thus providing good assemblability. There is no need to consider the insertion direction of the spring 30 into the barrel portion 11 during assembly.

[0025] (5) The central axis a of the first winding section 32 and the central axis b of the second winding section 33 are offset (eccentric) in the same direction with respect to the central axis c of the loosely wound section 31. Furthermore, the outer peripheral end of the loosely wound section 31 and the outer peripheral end of the first winding section 32 are aligned on opposite sides of the offset direction with respect to the central axis c of the loosely wound section 31. That is, in Figure 1, etc., the lower part of the loosely wound section 31 is aligned with the lower part of the first winding section 32. Also, the outer peripheral end of the loosely wound section 31 and the outer peripheral end of the second winding section 33 are aligned on opposite sides of the offset direction with respect to the central axis c of the loosely wound section 31. That is, in Figure 1, etc., the lower part of the loosely wound section 31 is aligned with the lower part of the second winding section 33. From the above, the probe 1 is easy to manufacture.

[0026] The present invention has been described above using embodiments as examples, but it will be understood by those skilled in the art that various modifications are possible to each component and each processing step of the embodiments within the scope of the claims. Modifications will be discussed below.

[0027] In this embodiment, the first plunger is a single component having an integrated barrel portion, but it may also be a structure in which the hollow barrel portion and the tip portion are made of separate components and joined together to form a single unit.

[0028] In the embodiment, the first and second seated winding portions located on either side of the sparsely wound portion are shown as having a larger diameter; however, the first and second seated winding portions may also have a smaller diameter than the sparsely wound portion.

[0029] In the embodiment, the first plunger is shown to have multiple pointed protrusions at its tip, but it may have only one protrusion, and the shape and arrangement of the protrusions can be appropriately changed to correspond to bumps or electrodes on the object being inspected.

[0030] In this embodiment, the illustration shows the case where the spring 40 is right-handed when viewed from the first plunger 10, but it may also be left-handed.

[0031] According to this specification, probes in the following embodiments are provided. (Aspect 1) Embodiment 1 comprises a conductive first plunger having a hollow barrel portion, A conductive second plunger is slidably located within the barrel portion and protrudes from the open end of the barrel portion, The barrel portion is provided with a spring that biases the first plunger and the second plunger toward each other, The spring has a loosely wound portion, a first seated portion located at one end of the loosely wound portion and in contact with the first plunger, and a second seated portion located at the other end of the loosely wound portion and in contact with the second plunger, wherein the first seated portion and the second seated portion have different diameters from the loosely wound portion. The probe is such that the central axes of the first and second winding sections are offset in the same direction with respect to the central axis of the loosely wound section.

[0032] According to the above-described embodiment 1, the second plunger is pressed by the spring and stably contacts the inner wall of the barrel portion, and the contact resistance value between the first plunger and the second plunger can be stably maintained at a low value.

[0033] (Aspect 2) Embodiment 2 is characterized in that the first and second winding portions have larger diameters than the loosely wound portion.

[0034] According to the above-described embodiment 2, the formation of the first and second seat coil portions is easy even when the spring has a small diameter. In addition, the spring contacts the inner bottom surface of the first plunger with a large diameter, which stabilizes the holding of the end of the spring.

[0035] (Aspect 3) Embodiment 3 is characterized in that the first and second winding portions have smaller diameters than the loosely wound portion.

[0036] According to embodiment 3 described above, it becomes possible to reduce the outer diameter of the spring, which is advantageous when aiming to reduce the diameter of the probe.

[0037] (Aspect 4) In embodiment 4, the outer peripheral end of the loosely wound portion and the outer peripheral ends of the first and second seated winding portions are aligned on the outer side opposite to the offset direction with respect to the central axis of the loosely wound portion.

[0038] According to the above-described embodiment 4, the offset amount of the first and second seat winding portions relative to the loosely wound portion can be increased, and manufacturing is also easier.

[0039] (Appendix 5) Embodiment 5 is characterized in that a recess into which the first seat winding portion fits is formed on the inner bottom surface of the barrel portion.

[0040] According to embodiment 5 described above, the first seating portion sits stably on the inner bottom surface of the barrel portion. [Explanation of symbols]

[0041] 1 probe 10. First Plunger 11. Barrel section 12. Cylindrical hollow section 13 Tip 16 recesses 16a Bottom 20. Second plunger 21 Cylindrical hollow section 22 Immigration Department 23 Tip 30 Spring 31 Sparsely wrapped section 32. Chapter 1 33. Section 2 a. Central axis of the first winding section b. Central axis of the second winding section c. Central axis of the loosely wound section

Claims

1. A conductive first plunger having a hollow barrel portion, A conductive second plunger is slidably within the barrel portion and protrudes from the open end of the barrel portion, The barrel portion is provided with a spring that biases the first plunger and the second plunger toward each other, The spring has a loosely wound portion, a first seated portion located on one end of the loosely wound portion and in contact with the first plunger, and a second seated portion located on the other end of the loosely wound portion and in contact with the second plunger, wherein the first seated portion and the second seated portion have different diameters from the loosely wound portion. The central axes of the first and second winding sections are offset in the same direction with respect to the central axis of the loosely wound section. The loosely wound portion of the probe has the same diameter across the first and second winding portions.

2. The probe according to claim 1, wherein the first and second winding portions have a larger diameter than the loosely wound portion.

3. The probe according to claim 1, wherein the first and second winding portions have smaller diameters than the loosely wound portion.

4. The probe according to any one of claims 1 to 3, wherein the outer peripheral end of the loosely wound portion and the outer peripheral ends of the first and second seated winding portions are aligned on the outer side opposite to the offset direction with respect to the central axis of the loosely wound portion.

5. The probe according to any one of claims 1 to 3, wherein a recess into which the first seat winding portion fits is formed on the inner bottom surface of the barrel portion.

Images