Probe
Patent Information
- Application Number
- JP2022085829
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2022-05-26
- Publication Date
- 2025-05-26
AI Technical Summary
Conventional probes with non-eccentric springs fail to generate stable lateral pressure, leading to unstable resistance values, and probes with complex eccentric springs are difficult to manufacture.
A probe design featuring a spring with a loosely wound portion and offset end-turn portions that generate stable side pressure, maintaining consistent resistance values and facilitating easy assembly.
The design ensures stable contact resistance and easy manufacturing by using a simple spring structure with offset end-turn portions, allowing for reliable plunger interaction and consistent performance.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to a probe.
Background Art
[0002] Conventionally, as a probe, there is known a structure including a conductive first plunger having a hollow barrel portion, a conductive second plunger that is slidable within the barrel portion and protrudes from an open end of the barrel portion, and a spring that biases the first plunger and the second plunger in a direction away from each other.
[0003] However, since a conventional general spring does not have an eccentric structure, in the case of a probe, it is difficult to bend even when the spring is compressed. Therefore, it is difficult to generate a side pressure in a direction 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 unstable.
[0004] Also, Patent Document 1 below discloses a probe pin in which a portion in contact with a spring of a pin (hereinafter referred to as a pin bottom surface) is machined into a cone, and a spring is installed in a space formed by the pin and a hole of a tube. In this case, the spring has a central portion with substantially equal diameters, and a tapered portion adjacent thereto and gradually decreasing in diameter and the central axis of which is offset in an oblique direction from the central axis of the central portion, and is characterized by a curved shape as a whole. During use, both ends of the spring are compressed by the conical portion of the pin bottom surface and the bottom surface of the tube hole, and the pin receives a load in a direction inclined from the axial direction of the tube by the tapered portion of the spring. Therefore, the pin is in an inclined state, and the pin is pressed against the inner wall of the tube to generate a side pressure corresponding to the amount of axial compression of the spring. However, the structure of the spring is complex and may be time-consuming to manufacture.
Prior Art Documents
Patent Documents
[0005] <00... [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 no-load state of FIG. 1 to push the tip 23 of the second plunger 20, the spring 30 is compressed. At this time, due to the first seat winding portion 32 and the second seat winding portion 33 being formed at eccentric positions with respect to the sparse winding portion 41, the spring 30 deflects in an arch shape, or in other words, in a bow shape. As a result, the inner wall of the second plunger 20 is pushed by the spring 30, generating a side pressure in a direction to press the inlet portion 22 of the second plunger 20 against the inner wall of the barrel portion 11. Due to this side pressure, the inlet 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.
[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 in 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, the protrusion 14 of the first plunger 10 is brought into contact with the bump 111 of the inspection object 110, and the protrusion 24 provided at the tip 23 of the second plunger 20 is brought into contact with the electrode 121 of the inspection substrate 120. Thereby, an electrical connection is made between the bump 111 of the inspection object 110 and the inspection substrate 120 via the probe 1.
[0020] According to this embodiment, the following effects can be achieved.
[0021] (1) The first and second seat windings 32 and 33 of the spring 30 that urge the first plunger 10 and the second plunger 20 in the direction of separation from each other have a different diameter from the sparse winding part 41, and the central axes of the first and second seat windings 32 and 33 are offset (eccentric) in the same direction with respect to the central axis of the sparse winding part 31. For this reason, the spring 30 is likely to bend in an arch shape. As a result, the inner wall of the second plunger 20 is pushed by the spring 30, and the inlet pipe part 22 of the second plunger 20 stably contacts the inner wall of the barrel part 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 seat winding 32 and the second seat winding 33 of the spring 30 are made to have a larger diameter than the sparse winding part 31, it is easy to form the first and second seat windings 32 and 33 even when the spring 30 has a small diameter. Also, the spring 30 abuts against the inner bottom surface of the first plunger 10 with a large diameter, and the holding of the end part of the spring 30 is stabilized.
[0023] (3) The recess 16 into which the first seat winding 32 fits is formed on the inner bottom surface of the barrel part 11, and the bottom surface 16a of the recess 16 against which the first seat winding 32 abuts is a flat surface perpendicular to the central axis 11a of the barrel part 11. Therefore, the seating of the first seat winding 32 on the inner bottom surface of the first plunger 10 is stable. [[ID=?]]<00??104> (4) The spring 30 having the sparse winding part 31 and the first and second seat windings 32 and 33 on both sides thereof has a symmetric shape, and the same performance can be obtained even when it is upside down, so the assembly property is good. There is no need to consider the insertion direction of the spring 30 into the barrel part 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 shown, the first plunger has 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) In embodiment 3, 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 that is slidable within the barrel portion and protrudes from the open end of the barrel portion, A spring provided inside the barrel portion for biasing the first plunger and the second plunger away from each other, The spring has a sparse winding portion, a first seat winding portion located on one end side of the sparse winding portion and abutting against the first plunger, and a second seat winding portion located on the other end side of the sparse winding portion and abutting against the second plunger. The first seat winding portion and the second seat winding portion have different diameters from the sparse winding portion, The central axes of the first seat winding portion and the second seat winding portion are offset in the same direction with respect to the central axis of the sparse winding portion, The sparse winding portion has the same diameter across between the first seat winding portion and the second seat winding portion, the probe.
2. The probe according to claim 1, wherein the first seat winding portion and the second seat winding portion have a larger diameter than the sparse winding portion.
3. The probe according to claim 1, wherein the first seat winding portion and the second seat winding portion have a smaller diameter than the sparse winding portion.
4. The probe according to any one of claims 1 to 3, wherein the outer peripheral ends of the sparse winding portion and the outer peripheral ends of the first seat winding portion and the second seat winding portion are aligned on the outer side opposite to the offset direction with respect to the central axis of the sparse winding portion.
5. The probe according to any one of claims 1 to 3, wherein a recess for fitting the first seat winding portion is formed on the inner bottom surface of the barrel portion.
6. A conductive first plunger having a hollow barrel portion, A conductive second plunger that is slidable within the barrel portion and protrudes from the open end of the barrel portion, A spring provided inside the barrel portion for biasing the first plunger and the second plunger away from each other, The spring has a sparse winding portion, a first seat winding portion located on one end side of the sparse winding portion and abutting against the first plunger, and a second seat winding portion located on the other end side of the sparse winding portion and abutting against the second plunger. The first seat winding portion and the second seat winding portion have different diameters from the sparse winding portion, The central axes of the first seat winding portion and the second seat winding portion are offset in the same direction with respect to the central axis of the sparse winding portion, The first plunger has a recess on the inner bottom surface of the barrel portion for fitting the first seat winding portion, and the bottom surface of the recess is formed as a flat surface perpendicular to the central axis of the barrel portion, the probe.