Inspection probe
The inspection probe's innovative plunger and ground pin configuration with a ring portion stabilizes the connection, preventing resonance and maintaining accuracy by reducing stray capacitance, addressing the test accuracy issues in conventional probes.
Patent Information
- Application Number
- JP2023113627
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-07-11
- Publication Date
- 2025-01-24
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
Conventional inspection probes experience reduced test accuracy due to unpredictable resonance caused by gaps between the ground conductor and plunger, leading to floating capacity issues.
The inspection probe design includes a plunger with a concave portion and a ground pin featuring a ring portion with a larger outer diameter than the pin, supported by the concave's side, preventing deformation and gap formation, thus stabilizing the connection and reducing stray capacitance.
This design effectively suppresses unpredictable resonance, maintaining test accuracy by minimizing stray capacitance and ensuring stable electrical connections, even with high-frequency signals.
Smart Images
Figure 2025011485000001_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to a testing probe that is connected to a connector to test an electronic device that is equipped with the connector. [Background technology]
[0002] As an invention related to a conventional inspection probe, for example, a connector measurement probe described in Patent Document 1 is known. The connector measurement probe described in Patent Document 1 is connected to a connector to be measured. The connector to be measured includes a signal terminal for inputting and outputting a high-frequency signal and a ground terminal. The connector measurement probe described in Patent Document 1 includes a plurality of probe parts, a conductive plunger, and a ground conductor part. Each of the plurality of probe parts has a central conductor that contacts the signal terminal of the connector to be measured. The plunger has an insertion hole for inserting each of the plurality of probe parts. The tip of the central conductor is configured to be able to protrude from the main surface of the plunger toward the connector to be measured, so that it can contact the signal terminal of the connector to be measured. The ground conductor part is electrically connected to the plunger. The ground conductor part has a protrusion protruding from the main surface of the plunger toward the connector to be measured between adjacent central conductors, so that it contacts the ground terminal of the connector to be measured.
[0003] In the connector measurement probe described in Patent Document 1, the ground conductor may be used as a probe pin (see FIG. 21). The ground conductor is press-fitted into the plunger. The ground conductor elastically protrudes from the main surface of the plunger toward the connector under test due to a coil spring inside the ground conductor. The ground conductor contacts the top surface or tapered portion of the ground terminal of the connector under test. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] WO 2021 / 60189 Summary of the Invention [Problem to be solved by the invention]
[0005] If a gap occurs between the ground conductor and the plunger, it becomes impossible to identify the contact point between the ground conductor and the plunger. In addition, if a gap occurs between the ground conductor and the plunger, an unpredictable stray capacitance occurs between the ground conductor and the plunger. Since the measurement target of the connector measurement probe described in Patent Document 1 is a connector that inputs and outputs high-frequency signals, if an unpredictable stray capacitance occurs, there is a risk of the inspection accuracy decreasing due to unpredictable resonance.
[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide an inspection probe capable of suppressing a decrease in inspection accuracy due to unpredictable resonance. [Means for solving the problem]
[0007] An inspection probe according to one embodiment of the present invention comprises: A test probe to be connected to a connector having a connector ground terminal and a connector signal terminal, A plunger connected to a ground potential; a signal pin connected to the connector signal terminal; a ground pin connected to the connector ground terminal; It is equipped with The plunger has a major surface, The main surface is provided with a recess that is recessed in an upward direction, The ground pin is a pin body located within the recess; a pin tip portion extending downward from the pin body; A ring portion located within the recess; Contains the pin tip portion protrudes from the main surface in the downward direction, the ring portion has an outer diameter larger than an outer diameter of the pin body when viewed in the upward direction, and is supported by a side surface of the recess, The upper end of the pin body does not contact the side surface of the recess.
[0008] The ring portion has an outer diameter larger than the outer diameter of the pin body when viewed from above. Therefore, the mechanical strength of the ring portion is higher than the mechanical strength of the pin body. Therefore, the ring portion is less likely to deform than the pin body. Because the ring portion, which is less likely to deform, is supported by the side surface of the recess, a gap is less likely to occur between the ring portion and the side surface of the recess. As a result, the occurrence of unpredictable stray capacitance is suppressed. Therefore, this embodiment can suppress the occurrence of unpredictable resonance and suppress a decrease in inspection accuracy. Effect of the Invention
[0009] According to the inspection probe of the present invention, it is possible to suppress a decrease in inspection accuracy due to unpredictable resonance. [Brief description of the drawings]
[0010] [Figure 1] FIG. 1 is a front view of the inspection unit 100. FIG. [Diagram 2] FIG. 2 is a perspective view of the lower end of the coaxial cable 3a. [Diagram 3] FIG. 3 is a cross-sectional view showing the inside of the inspection probe 1. As shown in FIG. [Figure 4] FIG. 4 is a cross-sectional view showing the inside of plunger 8, coaxial cable 3a, coaxial cable 3b, coaxial cable 3c, ground pin 10a, ground pin 10b, ground pin 10c, and ground pin 10d. [Diagram 5] FIG. 5 is a plan view of the main surface S1 viewed from above. [Figure 6] FIG. 6 is a cross-sectional view showing the inside of the plunger 8 and the ground pin 10a. [Figure 7] FIG. 7 is a perspective view of the connector 200. [Figure 8]FIG. 8 is a cross-sectional view of the lower part of the inspection probe 1 and the connector 200 when the inspection probe 1 is connected to the connector 200. As shown in FIG. [Figure 9] FIG. 9 is a cross-sectional view showing a current path that flows through the ground pin 10c and the signal probe 9c when the inspection probe 1 is connected to the connector 200. As shown in FIG. [Figure 10] FIG. 10 is a cross-sectional view showing an example of a ground pin 10a including a plurality of ring portions 10a4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0011] [Embodiment] The inspection unit 100 according to the embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of the inspection unit 100. FIG. 2 is a perspective view of the lower end of the coaxial cable 3a. FIG. 3 is a cross-sectional view showing the inside of the inspection probe 1. In FIG. 3, the plunger 8, the signal probe 9a, the signal probe 9b, the signal probe 9c, the ground pin 10a, the ground pin 10b, the ground pin 10c, and the ground pin 10d are simplified for the purpose of explanation. FIG. 4 is a cross-sectional view showing the inside of the plunger 8, the coaxial cable 3a, the coaxial cable 3b, the coaxial cable 3c, the ground pin 10a, the ground pin 10b, the ground pin 10c, and the ground pin 10d. FIG. 5 is a plan view of the main surface S1 viewed in the upward direction. FIG. 6 is a cross-sectional view showing the inside of the plunger 8 and the ground pin 10a. FIG. 7 is a perspective view of the connector 200. FIG. 8 is a cross-sectional view of the lower part of the inspection probe 1 and the connector 200 when the inspection probe 1 is connected to the connector 200. Fig. 8 shows an example of a connection structure between the inspection probe 1 and the connector 200. Fig. 8 shows the connection structure between the inspection probe 1 and the connector 200 when the signal probe 9a is connected to the connector signal terminal 201r, the signal probe 9b is connected to the connector signal terminal 201t, the signal probe 9c is connected to the connector signal terminal 201v, the ground pin 10a is connected to the connector ground terminal 202a, the ground pin 10b is connected to the connector ground terminal 202c, the ground pin 10c is connected to the connector ground terminal 202d, and the ground pin 10d is connected to the connector ground terminal 202f.
[0012] In this specification, the directions are defined as follows. As shown in FIG. 8, when the inspection probe 1 is connected to the connector 200, the direction in which the inspection probe 1 and the connector 200 are arranged in this order is defined as the downward direction. The opposite direction of the downward direction is defined as the upward direction. As shown in FIG. 1, the direction in which the lower ends of the coaxial cables 3a, 3b, and 3c are arranged in this order is defined as the rightward direction. The opposite direction of the rightward direction is defined as the leftward direction. The rightward and leftward directions are perpendicular to the downward and upward directions. In addition, the direction perpendicular to the upward and downward directions is defined as the forward direction. The opposite direction of the forward direction is defined as the rearward direction. However, the downward, upward, rightward, leftward, forward, and rearward directions in this specification are directions defined for the convenience of explanation, and may not match the downward, upward, rightward, leftward, forward, and rearward directions when the inspection probe 1 is in use.
[0013] The inspection unit 100 is used to measure high frequency signals transmitted by a connector 200 mounted on a circuit board or the like of an electronic device. As shown in Fig. 1, the inspection unit 100 includes an inspection probe 1, an external connection connector 2a, an external connection connector 2b, an external connection connector 2c, a coaxial cable 3a, a coaxial cable 3b, and a coaxial cable 3c.
[0014] Each of the external connection connectors 2a, 2b, and 2c is connected to a measuring device (not shown). The external connection connectors 2a, 2b, and 2c have a common structure, and therefore their description will be omitted.
[0015] As shown in FIG. 1, the coaxial cables 3a, 3b, and 3c are inserted into the inspection probe 1 and the external connector 2a, 2b, and 2c, respectively. As a result, the coaxial cables 3a, 3b, and 3c electrically connect the inspection probe 1 to the external connector 2a, 2b, and 2c, respectively. The lower ends of the coaxial cables 3a, 3b, and 3c are aligned in a line in this order along the right direction. The coaxial cables 3a, 3b, and 3c have the same structure. The coaxial cables 3a, 3b, and 3c have a general structure. Therefore, the structure of the coaxial cable 3a will be briefly described as an example, and the description of the coaxial cables 3b and 3c will be omitted.
[0016] The coaxial cable 3a has a cylindrical shape extending in the up-down direction. As shown in FIG. 2, the coaxial cable 3a includes a central conductor 3a1, an insulator 3b1, an outer conductor 3a2, and a coating 3b2. The central conductor 3a1 is the core of the coaxial cable 3a. When viewed in the direction in which the coaxial cable 3a extends, the central conductor 3a1 is located at the center of the coaxial cable 3a. When viewed in the direction in which the coaxial cable 3a extends, the central conductor 3a1 has a circular shape. The central conductor 3a1 is made of a conductor having a low resistance value, such as copper.
[0017] The insulator 3b1 electrically insulates the central conductor 3a1 from the outer conductor 3a2. The insulator 3b1 surrounds the central conductor 3a1. The insulator 3b1 is located between the central conductor 3a1 and the outer conductor 3a2. The insulator 3b1 has a ring shape when viewed in the extending direction of the coaxial cable 3a. The insulator 3b1 is made of an insulating resin such as polyethylene.
[0018] The outer conductor 3a2 surrounds the insulator 3b1. The outer conductor 3a2 has a ring shape when viewed in the direction in which the coaxial cable 3a extends. The outer conductor 3a2 is connected to a ground potential. The outer conductor 3a2 is made, for example, by braiding thin conductive wires. The outer conductor 3a2 is made, for example, of a conductor having a low resistance value, such as copper.
[0019] The coating 3b2 surrounds the outer conductor 3a2. The coating 3b2 has a ring shape when viewed in the extending direction of the coaxial cable 3a. The coating 3b2 is made of an insulating resin such as polyethylene.
[0020] As shown in Fig. 1, the inspection probe 1 is connected to the lower end of the coaxial cable 3a, the lower end of the coaxial cable 3b, and the lower end of the coaxial cable 3c. As shown in Fig. 3, the inspection probe 1 includes a housing 4, a flange 5, a spring 6, a spacer 7, a plunger 8, a signal probe 9a, a signal probe 9b, a signal probe 9c, a ground pin 10a, a ground pin 10b, a ground pin 10c, and a ground pin 10d.
[0021] The housing 4 is a cylindrical member extending in the up-down direction. The housing 4 is provided with a first through hole H1 extending in the up-down direction. The first through hole H1 penetrates the housing 4 from the upper end to the lower end. The upper end of the housing 4 is inserted into the housing 4. The lower end of the housing 4 is inserted into an upper portion of the plunger 8. The coaxial cables 3a, 3b, and 3c pass through the first through hole H1 in the up-down direction. The housing 4 is made of a conductor such as SUS (Stainless Used Steel).
[0022] The flange 5 is a plate-shaped member. When viewed from below, the flange 5 has a rectangular shape. The flange 5 is disposed near the upper end of the housing 4. The flange 5 is provided with a second through hole (not shown) extending along the up-down direction. The second through hole penetrates the flange 5 from the upper end to the lower end. The housing 4 passes through the second through hole in the upward direction. However, the diameter of the upper end of the housing 4 is larger than the diameter of the second through hole of the flange 5. Therefore, the housing 4 cannot pass through the second through hole in the downward direction. The flange 5 is made of a conductor such as SUS (Stainless Used Steel).
[0023] The spring 6 pushes the flange 5 upward. The spring 6 pushes the plunger 8 downward. More specifically, the upper end of the spring 6 is fixed to the lower surface of the flange 5. The lower end of the spring 6 is fixed to the upper end of the plunger 8. Therefore, when the plunger 8 is pushed upward, the spring 6 contracts, and the plunger 8 and the housing 4 are displaced upward relative to the flange 5. In other words, the flange 5, the plunger 8, and the housing 4 are elastically connected by the spring 6.
[0024] The spacer 7 is disposed between the housing 4 and the plunger 8 in the up-down direction. The spacer 7 has a disk shape. The spacer 7 has a slit extending in the left-right direction when viewed from below. The coaxial cables 3a, 3b, and 3c pass through the slit in the up-down direction. In this way, the spacer 7 positions the coaxial cables 3a, 3b, and 3c in the front-rear and left-right directions. The spacer 7 is made of a conductor such as SUS (Stainless Used Steel).
[0025] The plunger 8 is provided with three third through holes H3 extending in the up-down direction. The third through holes H3 penetrate the plunger 8 from the upper end to the lower end. The coaxial cables 3a, 3b, and 3c are connected to the signal probes 9a, 9b, and 9c, respectively, in the third through holes H3. The connection structures between the coaxial cables and the signal probes are the same. Therefore, the connection structure between the coaxial cable 3a and the signal probe 9a will be described as an example, and the connection structure between the coaxial cable 3b and the signal probe 9b and the connection structure between the coaxial cable 3c and the signal probe 9c will not be described.
[0026] 4, the coating 3b2, the outer conductor 3a2, and the insulator 3b1 are removed from the lower end of the coaxial cable 3a, so that the central conductor 3a1 is exposed from the coaxial cable 3a. Also, the coating 3b2 is removed above the portion where the central conductor 3a1 is exposed, so that the outer conductor 3a2 is exposed from the coaxial cable 3a.
[0027] A high frequency signal is applied to the signal probe 9a. The signal probe 9a has a shape that extends in the vertical direction. The signal probe 9a includes a barrel 9a1, a socket 9a2, a signal pin 9a3, and an insulating support member 9a4.
[0028] The barrel 9a1 has a cylindrical shape with a central axis extending along the up-down direction. The upper and lower ends of the barrel 9a1 are open. The barrel 9a1 is not in contact with the central conductor 3a1. The barrel 9a1 is not electrically connected to the central conductor 3a1. However, the inner surface of the barrel 9a1 is in contact with the outer conductor 3a2. As a result, the barrel 9a1 is electrically connected to the outer conductor 3a2. Therefore, the barrel 9a1 is connected to the ground potential. In addition, at the lower end of the barrel 9a1, the outer surface of the barrel 9a1 is in contact with the plunger 8. As a result, the barrel 9a1 is electrically connected to the plunger 8. Therefore, the plunger 8 is connected to the ground potential. Note that, in a portion other than the lower end of the barrel 9a1, an insulating member (not shown) is located between the outer surface of the barrel 9a1 and the plunger 8, and the outer surface of the barrel 9a1 is not in contact with the plunger 8. The barrel 9a1 is made of a conductor such as brass.
[0029] The socket 9a2 supports the central conductor 3a1. Specifically, the socket 9a2 has a cylindrical shape. The upper end of the socket 9a2 is open. The lower end of the central conductor 3a1 is inserted into the socket 9a2 from the upper end of the socket 9a2. The central conductor 3a1 is fixed to the socket 9a2 by solder (not shown). As a result, the socket 9a2 is electrically connected to the central conductor 3a1. However, the socket 9a2 is not electrically connected to the outer conductor 3a2.
[0030] The socket 9a2 is located within the barrel 9a1. As a result, the socket 9a2 is surrounded by the barrel 9a1 when viewed from below. The socket 9a2 is made of a conductor such as brass.
[0031] A high frequency signal is applied to the signal pin 9a3. The signal pin 9a3 is a rod-shaped member extending in the vertical direction. More specifically, the upper end of the signal pin 9a3 is fixed to the lower end of the socket 9a2. This allows the signal pin 9a3 to be electrically connected to the socket 9a2. Therefore, the signal pin 9a3 is electrically connected to the central conductor 3a1.
[0032] The signal pin 9a3 extends downward from the socket 9a2. At least a portion of the signal pin 9a3 is located inside the barrel 9a1. However, a lower end of the signal pin 9a3 protrudes downward from the barrel 9a1 and the plunger 8.
[0033] The signal pin 9a3 has a cylindrical portion 9a31, a pin tip portion 9a32, and a spring 9a33. The signal pin 9a3 is made of a conductor such as brass.
[0034] The tubular portion 9a31 has a cylindrical shape with a central axis extending in the up-down direction. The central axis of the tubular portion 9a31 coincides with the central axis of the barrel 9a1. The upper end of the tubular portion 9a31 is not open. The lower end of the tubular portion 9a31 is open. The lower end of the tubular portion 9a31 has a tapered shape, and the pin tip portion 9a32 is crimped.
[0035] The pin tip 9a32 is a rod-shaped member extending in the up-down direction. An upper portion of the pin tip 9a32 is located inside the cylindrical portion 9a31. The pin tip 9a32 protrudes downward from the cylindrical portion 9a31 and the plunger 8. However, the width of the upper portion of the pin tip 9a32 is greater than the width of the lower portion of the pin tip 9a32. As a result, the pin tip 9a32 cannot pass downward through the opening at the lower end of the cylindrical portion 9a31.
[0036] The spring 9a33 is provided inside the cylindrical portion 9a31. The upper end of the spring 9a33 contacts the inner circumferential surface of the cylindrical portion 9a31. The lower end of the spring 9a33 contacts the upper end of the pin tip portion 9a32.
[0037] The spring 9a33 presses the pin tip 9a32 downward. When the pin tip 9a32 is pressed upward, the spring 9a33 contracts and the pin tip 9a32 is displaced upward relative to the plunger 8.
[0038] The insulating support member 9a4 has a ring shape surrounding the signal pin 9a3 when viewed from below. The insulating support member 9a4 has a cylindrical shape with a central axis extending along the vertical direction. The central axis of the insulating support member 9a4 coincides with the central axis of the barrel 9a1. The insulating support member 9a4 is disposed at the lower end of the barrel 9a1 within the barrel 9a1. The signal pin 9a3 extends in the vertical direction within the insulating support member 9a4. As a result, the insulating support member 9a4 is supported by the barrel 9a1 and supports the signal pin 9a3. The insulating support member 9a4 is made of, for example, an insulating epoxy resin. As a result, the signal pin 9a3 is electrically insulated from the barrel 9a1.
[0039] The plunger 8 has a main surface S1 as shown in FIG. 4 and FIG. 5. The main surface S1 is located at the lower end of the inspection probe 1. The main surface S1 has a recess G recessed upward as shown in FIG. 4 and FIG. 6. The ground pins 10a, 10b, 10c, and 10d are connected to the plunger 8 in the recess G. The ground pins 10a, 10b, 10c, and 10d have the same structure as each other. The connection structures between the ground conductor portion and the plunger 8 are the same as each other. Therefore, the structure of the ground pin 10a and the connection structure between the ground pin 10a and the plunger 8 will be described as an example, and the connection structures between the ground pin 10b and the plunger 8, the connection structure between the ground pin 10c and the plunger 8, and the connection structure between the ground pin 10d and the plunger 8 will not be described.
[0040] The ground pin 10a has a shape extending in the vertical direction. A part of the ground pin 10a is located in the recess G. In this embodiment, most of the ground pin 10a is located in the recess G. As shown in FIG. 6, the ground pin 10a includes a tubular portion 10a1, a pin tip portion 10a2, a spring 10a3, and a ring portion 10a4. The ground pin 10a is made of a conductor such as brass. The ring portion 10a4 may be integrated with the tubular portion 10a1 or the pin tip portion 10a2. However, the tubular portion 10a1 is not an essential component. Also, most of the ground pin 10a does not necessarily have to be located in the recess G.
[0041] The tubular portion 10a1 has a tubular shape extending along the vertical direction. In this embodiment, the tubular portion 10a1 has a cylindrical shape having a central axis extending along the vertical direction. The upper end of the tubular portion 10a1 is not open. The lower end of the tubular portion 10a1 is open. The lower end of the tubular portion 10a1 has a tapered shape and the pin tip portion 10a2 is swaged. The tubular portion 10a1 is in contact with the ring portion 10a4. The tubular portion 10a1 is located in the recess G. However, the upper end of the tubular portion 10a1 is not in contact with the side surface of the recess G. In this embodiment, the entire tubular portion 10a1 is not in contact with the side surface of the recess G. The outer diameter of the tubular portion 10a1 is smaller than the inner diameter of the recess G. The outer diameter of the tubular portion 10a1 is the diameter of the outer surface of the tubular portion 10a1 when viewed in the upward direction. The inner diameter of the recess G is the diameter of the side surface of the recess G when viewed in the upward direction. Moreover, the upper end of the tube portion 10a1 is located below the upper end of the recess G. Note that the tube portion 10a1 does not have to have a cylindrical shape having a central axis that extends along the up-down direction.
[0042] The pin tip 10a2 is a rod-shaped member extending in the up-down direction. The pin tip 10a2 extends downward from the spring 10a3. The upper part of the pin tip 10a2 is located in the recess G. The lower end of the pin tip 10a2 is not located in the recess G. In this embodiment, the lower end of the pin tip 10a2 is chamfered. The pin tip 10a2 protrudes downward from the main surface S1 of the plunger 8. However, the upper part of the pin tip 10a2 is located in the tube part 10a1. In addition, the width of the upper part of the pin tip 10a2 is larger than the width of the lower part of the pin tip 10a2. As a result, the pin tip 10a2 cannot pass through the opening at the lower end of the tube part 10a1 in the downward direction. The pin tip 10a2 is in contact with the tube part 10a1 and the spring 10a3. However, the pin tip 10a2 is not in contact with the side of the recess G. The width of the pin tip portion 10a2 is smaller than the inner diameter of the recess G. The lower end of the pin tip portion 10a2 does not have to be chamfered.
[0043] The spring 10a3 is provided in the cylindrical portion 10a1. The spring 10a3 is located in the recess G. However, the upper end of the spring 10a3 does not contact the side surface of the recess G. In this embodiment, the entire spring 10a3 does not contact the side surface of the recess G. The outer diameter of the spring 10a3 is smaller than the inner diameter of the recess G. The outer diameter of the spring 10a3 is the diameter of the spring 10a3 as viewed from above. In addition, the upper end of the spring 10a3 is located below the upper end of the recess G. The upper end of the spring 10a3 contacts the inner peripheral surface of the cylindrical portion 10a1. The lower end of the spring 10a3 contacts the upper end of the pin tip portion 10a2.
[0044] Spring 10a3 presses pin tip 10a2 downward. When pin tip 10a2 is pressed upward, spring 10a3 contracts and pin tip 10a2 is displaced upward relative to plunger 8. Spring 10a3 including at least spring 10a3 and the upper part of tubular portion 10a1 correspond to the "pin body" of the present invention. The "pin body" of the present invention does not have to be a spring.
[0045] The ring portion 10a4 is located in the recess G. The ring portion 10a4 has a cylindrical shape extending along the vertical direction. In this embodiment, the ring portion 10a4 has a cylindrical shape having a central axis extending along the vertical direction. The ring portion 10a4 has an outer diameter larger than the outer diameter of the spring 10a3 and the upper part of the cylindrical portion 10a1. The central axis of the ring portion 10a4 coincides with the central axis of the cylindrical portion 10a1. In this embodiment, the ring portion 10a4 is disposed near the lower end of the cylindrical portion 10a1. In addition, the length L1 of the ring portion 10a4 along the vertical direction is shorter than the length L2 of the spring 10a3 and the upper part of the cylindrical portion 10a1 along the vertical direction. Note that the ring portion 10a4 does not have to have a cylindrical shape having a central axis extending along the vertical direction.
[0046] The ring portion 10a4 is supported by the plunger 8. More specifically, the ring portion 10a4 is press-fitted into the recess G. As a result, the ring portion 10a4 is supported by the side surface of the recess G. That is, the ring portion 10a4 is in contact with the side surface of the recess G. Therefore, the ring portion 10a4 is electrically connected to the plunger 8 and is connected to the ground potential. As a result, the ground pin 10a is connected to the ground potential.
[0047] In this embodiment, the first distance A along the vertical direction from the upper end of the ring portion 10a4 to the main surface S1 is shorter than the second distance B along the vertical direction from the upper end of the ring portion 10a4 to the upper end of the recess G. In addition, when the wavelength of the high-frequency signal emitted by the measuring device is λ, the first distance A is longer than 0 and less than 1 / 2λ. When the frequency of the high-frequency signal emitted by the measuring device is a millimeter wave of 40 GHz, the length of the wavelength λ of the high-frequency signal is about 7.5 mm. Therefore, it is desirable that the first distance A is longer than 0 and less than 3.75 mm. In addition, the first distance A along the vertical direction from the upper end of the ring portion 10a4 to the main surface S1 may be equal to or greater than the second distance B along the vertical direction from the upper end of the ring portion 10a4 to the upper end of the recess G. In addition, the first distance A may be equal to or greater than 1 / 2λ.
[0048] In this embodiment, the inner diameter C of the lower end of the recess G is larger than the inner diameter D of the upper end of the recess G. The inner diameter C of the lower end of the recess G is the diameter of the lower end of the side of the recess G when viewed from above. The inner diameter D of the upper end of the recess G is the diameter of the upper end of the side of the recess G when viewed from above. The inner diameter C of the lower end of the recess G may be equal to the inner diameter D of the upper end of the recess G.
[0049] Next, the structure of the connector 200 will be described with reference to the drawings.
[0050] The connector 200 includes connector signal terminals 201a to 201v, connector ground terminals 202a to 202f, and a connector body 203, as shown in FIG.
[0051] The connector body 203 has a rectangular shape when viewed from below. The connector body 203 includes a protrusion 203a, a frame portion 203b, and a connecting portion 203c. The protrusion 203a has a rectangular parallelepiped shape. The protrusion 203a extends in the left-right direction. The connector body 203 holds connector signal terminals 201a to 201v and connector ground terminals 202a to 202f. The material of the connector body 203 is, for example, a resin having insulating properties.
[0052] The frame portion 203b has a ring shape surrounding the periphery of the protrusion portion 203a when viewed from below. The frame portion 203b has a rear end portion and a front end portion extending along the left-right direction, and a left end portion and a right end portion extending along the front-rear direction.
[0053] The connecting portion 203c is located between the protruding portion 203a and the frame portion 203b when viewed from below, and connects the protruding portion 203a to the frame portion 203b. More specifically, the connecting portion 203c connects the lower end of the protruding portion 203a to the lower end of the frame portion 203b.
[0054] A high frequency signal is applied to each of the connector signal terminals 201a to 201v. The connector signal terminals 201a to 201k are lined up in this order along the right direction at the rear of the connector 200. The connector signal terminals 201l to 201v are lined up in this order along the right direction at the front of the connector 200.
[0055] The connector ground terminals 202a to 202f are connected to a ground potential. The connector ground terminal 202a covers a part of the rear end of the frame portion 203b at the left side of the connector 200. The connector ground terminal 202b covers a part of the left end of the frame portion 203b at the left side of the connector 200. The connector ground terminal 202c covers a part of the front end of the frame portion 203b at the left side of the connector 200. The connector ground terminal 202d covers a part of the rear end of the frame portion 203b at the right side of the connector 200. The connector ground terminal 202e covers a part of the right end of the frame portion 203b at the right side of the connector 200. The connector ground terminal 202f covers a part of the front end of the frame portion 203b at the right side of the connector 200.
[0056] A portion of each of the connector signal terminals 201a to 201v and a portion of each of the connector ground terminals 202a to 202f are exposed from the connector body 203 when viewed in the downward direction.
[0057] Next, a connection structure between the inspection probe 1 and the connector 200 will be described with reference to the drawings.
[0058] The inspection probe 1 is connected to the connector 200 as shown in FIG. 8. When the inspection probe 1 is connected to the connector 200, the inspection probe 1 is located above the connector 200. The signal probe 9a comes into contact with the connector signal terminal 201r because the signal pin 9a3 protrudes downward from the main surface S1. As a result, the signal probe 9a (signal pin 9a3) is connected to the connector signal terminal 201r. Similarly, the signal probe 9b is connected to the connector signal terminal 201t. The signal probe 9c is connected to the connector signal terminal 201v. The ground pin 10a comes into contact with the connector ground terminal 202a because the pin tip portion 10a2 protrudes downward from the main surface S1. As a result, the ground pin 10a is connected to the connector ground terminal 202a. Similarly, the ground pin 10b is connected to the connector ground terminal 202c. The ground pin 10c is connected to the connector ground terminal 202d. The ground pin 10d is connected to the connector ground terminal 202f.
[0059] [effect] The inspection probe 1 can suppress the deterioration of inspection accuracy due to unpredictable resonance. As a comparative example, an inspection probe 50 in which the ground pin 10a does not include the ring portion 10a4 and the tubular portion 10a1 is supported on the side surface of the recess G will be described. In the case of the inspection probe 50 according to the comparative example, the tubular portion 10a1 comes into contact with the side surface of the recess G, thereby being electrically connected to the plunger 8 and connected to the ground potential. As a result, the ground pin 10a is connected to the ground potential.
[0060] In the case of the inspection probe 50 according to the comparative example, the outer diameter of the tube portion 10a1 is uniform, and a gap is likely to occur between the tube portion 10a1 and the side surface of the recess G. When a gap occurs between the tube portion 10a1 and the side surface of the recess G, it becomes impossible to identify the contact point between the tube portion 10a1 and the side surface of the recess G. In addition, when a gap occurs between the tube portion 10a1 and the side surface of the recess G, an unpredictable stray capacitance occurs between the tube portion 10a1 and the side surface of the recess G. Since the measurement target of the inspection probe according to the present invention is a connector through which high-frequency signals are input and output, when an unpredictable stray capacitance occurs, unpredictable resonance is likely to occur, and there is a risk of a decrease in inspection accuracy.
[0061] In addition, since the tube portion 10a1 is thin, when the tube portion 10a1 comes into contact with the side surface of the recess G during insertion into the recess G, the tube portion 10a1 is likely to deform. Therefore, a gap is likely to occur between the tube portion 10a1 and the side surface of the recess G. In addition, when the tube portion 10a1 deforms, the distance between the tube portion 10a1 and the side surface of the recess G changes, and the stray capacitance changes. The change in stray capacitance also makes it easier for unpredictable resonance to occur, which may reduce the inspection accuracy.
[0062] When the cylindrical portion 10a1 is press-fitted into the recess G, the spring 10a3 may not function due to deformation of the cylindrical portion 10a1. In this case as well, the inspection accuracy may decrease.
[0063] On the other hand, according to the inspection probe 1 of this embodiment, the ground pin 10a includes a ring portion 10a4. The ring portion 10a4 has an outer diameter larger than the outer diameter of the spring 10a3 and the upper portion of the tubular portion 10a1. As a result, the ring portion 10a4 is thicker than each of the tubular portion 10a1, the pin tip portion 10a2, and the spring 10a3. Therefore, the mechanical strength of the ring portion 10a4 is higher than each of the tubular portion 10a1, the pin tip portion 10a2, and the spring 10a3. Therefore, the ring portion 10a4 is less likely to deform than each of the tubular portion 10a1, the pin tip portion 10a2, and the spring 10a3. Since the ring portion 10a4, which has a high mechanical strength, is supported by the side surface of the recess G, a gap is less likely to occur between the ring portion 10a4 and the side surface of the recess G. Therefore, unpredictable stray capacitance is less likely to occur, and unpredictable resonance is less likely to occur. In addition, since the ring portion 10a4, which has high mechanical strength, is supported on the side surface of the recess G, the distance between each of the tube portion 10a1, the pin tip portion 10a2, and the spring 10a3 and the side surface of the recess G is stable, the stray capacitance is unlikely to change, and unpredictable resonance is unlikely to occur. In addition, the upper end of the tube portion 10a1 and the upper end of the spring 10a3 are not in contact with the side surface of the recess G. This makes it possible to prevent the ground pin 10a from easily bending due to the upper end of the tube portion 10a1 or the upper end of the spring 10a3 contacting the side surface of the recess G. Therefore, the inspection probe 1 can prevent a decrease in inspection accuracy due to unpredictable resonance. In addition, since the ring portion 10a4 is unlikely to deform, the risk of the spring 10a3 not functioning is also reduced. This also makes it possible to prevent a decrease in inspection accuracy.
[0064] In addition, the inspection probe 1 can further suppress the deterioration of the inspection accuracy due to unpredictable resonance. More specifically, the outer diameter of the upper part of the tube part 10a1 and the spring 10a3 is smaller than the inner diameter of the recess G. In addition, the upper end of the tube part 10a1 and the upper end of the spring 10a3 are located below the upper end of the recess G. Therefore, the upper part of the tube part 10a1 and the spring 10a3 are not in contact with the side of the recess G. This suppresses the deformation of the upper part of the tube part 10a1 and the spring 10a3 due to contact with the side of the recess G. Therefore, the distance between the tube part 10a1 and the spring 10a3 and the side of the recess G is stable, and the stray capacitance is less likely to change. As a result, the inspection probe 1 can further suppress the deterioration of the inspection accuracy due to unpredictable resonance.
[0065] Moreover, the inspection probe 1 can further suppress the deterioration of the inspection accuracy due to unpredictable resonance. Hereinafter, the description will be made with reference to the drawings. FIG. 9 is a cross-sectional view showing the current path flowing through the ground pin 10c and the signal probe 9c when the inspection probe 1 is connected to the connector 200. A first distance A along the vertical direction from the upper end of the ring portion 10a4 to the main surface S1 of the plunger 8 is shorter than a second distance B along the vertical direction from the upper end of the ring portion 10a4 to the upper end of the recess G. As a result, as shown in FIG. 9, when the inspection probe 1 is connected to the connector 200, the current I flowing through the ground pin 10c and the signal probe 9c flows through a shorter path without detouring the upper part of the ground pin 10c. Therefore, the value of the stray capacitance generated between the ring portion 10a4 and the side surface of the recess G can be reduced. As a result, the resonance frequency can be made higher than the frequency of the high-frequency signal generated by the measuring instrument. As a result, the inspection probe 1 can further suppress the deterioration of the inspection accuracy due to unpredictable resonance.
[0066] Moreover, the inspection probe 1 can further suppress the deterioration of the inspection accuracy due to unpredictable resonance. More specifically, when the frequency of the high-frequency signal generated by the measuring device is a millimeter wave of 40 GHz, the wavelength λ of the high-frequency signal is about 7.5 mm. Therefore, by setting the first distance A along the vertical direction from the upper end of the ring portion 10a4 to the main surface S1 to be longer than 0 and shorter than 3.75 mm, the deterioration of the inspection accuracy due to unpredictable resonance can be further suppressed.
[0067] Moreover, according to the inspection probe 1, the ground pin 10a can be smoothly inserted into the recess G. More specifically, when the inspection probe 1 is manufactured, the ground pin 10a is inserted into the recess G from below. Thus, the outer edge of the lower end of the recess G when viewed from above surrounds the outer edge of the upper end of the recess G when viewed from above. This allows the ground pin 10a to be smoothly inserted into the recess G without coming into contact with the lower end of the recess G.
[0068] [Other embodiments] The inspection probe according to the present invention is not limited to the inspection probe 1, and can be modified within the scope of the gist thereof.
[0069] 10 is a cross-sectional view showing an example of a ground pin 10a including a plurality of ring portions 10a4. Note that the ground pin 10a may include a plurality of ring portions 10a4 as shown in FIG.
[0070] The present invention has the following configuration.
[0071] (1) A test probe to be connected to a connector having a connector ground terminal and a connector signal terminal, A plunger connected to a ground potential; a signal pin connected to the connector signal terminal; a ground pin connected to the connector ground terminal; It is equipped with The plunger has a major surface, The main surface is provided with a recess that is recessed in an upward direction, The ground pin is a pin body located within the recess; a pin tip portion extending downward from the pin body; A ring portion located within the recess; Contains the pin tip portion protrudes from the main surface in the downward direction, the ring portion has an outer diameter larger than an outer diameter of the pin body when viewed in the upward direction, and is supported by a side surface of the recess, The upper end of the pin body does not contact the side surface of the recess. Inspection probe.
[0072] (2) The outer diameter of the pin body is smaller than the inner diameter of the recess, The upper end of the pin body is located below the upper end of the recess. An inspection probe as described in (1).
[0073] (3) a first distance along the vertical direction from an upper end of the ring portion to the main surface is shorter than a second distance along the vertical direction from the upper end of the ring portion to an upper end of the recess; An inspection probe according to (1) or (2).
[0074] (4) The first distance is greater than 0 and less than 3.75 mm. An inspection probe as described in (3).
[0075] (5) The inner diameter of the lower end of the recess is larger than the inner diameter of the upper end of the recess. An inspection probe according to any one of (1) to (4).
[0076] (6) The pin body is A cylindrical portion and A spring and It has The spring is provided within the cylindrical portion. An inspection probe according to any one of (1) to (5).
[0077] (7) The lower end of the cylindrical portion has a tapered shape and crimps the tip of the pin. An inspection probe as described in (6).
[0078] (8) The lower end of the pin tip is chamfered. An inspection probe according to any one of (1) to (7).
[0079] (9) A plurality of said ground pins are provided. An inspection probe according to any one of (1) to (8).
[0080] (10) A high frequency signal is applied to the signal pin. An inspection probe according to any one of (1) to (9). [Explanation of symbols]
[0081] 1: Inspection probe 2a to 2c: External connection connectors 3a~3c: Coaxial cable 3a1: Center conductor 3a2: Outer conductor 3b1: Insulator 3b2: Covering 4: Housing 5: Flange 6, 9a33, 10a3: Spring 7: Spacer 8: Plunger 9a-9c: Signal probes 9a1: Barrel 9a2:Socket 9a3: signal pin 9a31,10a1:Cylinder part 9a32, 10a2: Pin tip 9a4: Insulating support member 10a~10d: Ground pins 10a4: Ring section 100: Inspection unit 200: Connector 201a~201v: Connector signal terminals 202a~202f: Connector ground terminals 203: Connector body 203a: Protrusion 203b: Frame 203c: Connection part A: First distance B: 2nd distance G: Concave H1: 1st through hole H3: 3rd through hole S1: Main surface
Claims
1. A test probe to be connected to a connector having a connector ground terminal and a connector signal terminal, A plunger connected to a ground potential; a signal pin connected to the connector signal terminal; a ground pin connected to the connector ground terminal; Equipped with The plunger has a major surface, The main surface is provided with a recess that is recessed in an upward direction, The ground pin is a pin body located within the recess; a pin tip portion extending downward from the pin body; A ring portion located within the recess; Contains the pin tip portion protrudes from the main surface in the downward direction, the ring portion has an outer diameter larger than an outer diameter of the pin body when viewed in the upward direction, and is supported by a side surface of the recess, The upper end of the pin body does not contact the side surface of the recess. Inspection probe.
2. The outer diameter of the pin body is smaller than the inner diameter of the recess, The upper end of the pin body is located below the upper end of the recess.
2. The inspection probe according to claim 1.
3. a first distance along a vertical direction from an upper end of the ring portion to the main surface is shorter than a second distance along the vertical direction from an upper end of the ring portion to an upper end of the recess; 3. The inspection probe according to claim 1 or 2.
4. the first distance is greater than 0 and less than 3.75 mm; The inspection probe according to claim 3 .
5. The inner diameter of the lower end of the recess is larger than the inner diameter of the upper end of the recess.
3. The inspection probe according to claim 1 or 2.
6. The pin body is A cylindrical portion and A spring and It has The spring is provided within the cylindrical portion.
3. The inspection probe according to claim 1 or 2.
7. The lower end of the cylindrical portion has a tapered shape and crimps the tip of the pin.
7. The inspection probe according to claim 6.
8. The lower end of the pin tip is chamfered.
3. The inspection probe according to claim 1 or 2.
9. A plurality of said ground pins are provided.
3. The inspection probe according to claim 1 or 2.
10. A high frequency signal is applied to the signal pin.
3. The inspection probe according to claim 1 or 2.
Citation Information
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