Probes and probe devices

Abstract

To provide a probe and a probe device that can be simply attached to / detached from a circuit substrate, and can test the circuit substrate or an electronic component efficiently.SOLUTION: A first clamping piece 20 has a first clamping part 25 contacting one surface of a circuit substrate P in one end part located on a circuit substrate P side, and a second clamping piece 30 has a second clamping part 31 contacting the other surface of the circuit substrate P in the one end part located on the circuit substrate P side. The first clamping piece 20 and the second clamping piece 30 have operation parts 26 and 32 for receiving operation force against urging force of an urging member 40 in the other end part located on a side spaced apart from the circuit substrate P.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a probe connected to a circuit board and a probe device including the probe.

Background Art

[0002] Generally, when testing the electrical characteristics of a circuit board or an electronic component mounted on a circuit board, a measuring device measures the electrical characteristics obtained when a test signal is transmitted to the circuit board. At this time, the measuring device is connected to the circuit board via a cable or the like.

[0003] Patent Document 1 discloses a coaxial electrical connector connected to an end of a circuit board. This coaxial electrical connector has an axis parallel to the surface of the circuit board, and includes a central conductor extending in the axial direction, and a cylindrical outer conductor that holds the central conductor via an insulator. The outer conductor is provided with a pair of fixing portions for attachment to the circuit board, the fixing portions extending parallel to the surface of the circuit board. Each fixing portion is formed with an insertion hole that is a screw hole, penetrating in the vertical direction (a direction perpendicular to the surface of the circuit board). This coaxial electrical connector is attached to the end of the circuit board by screwing the fixing portions to the end. Specifically, the fixing portions are arranged on the upper surface of the end of the circuit board, and in a state where the insertion holes are aligned with holes formed in the circuit board, screws are screwed into the insertion holes and the holes.

Prior Art Literature

Patent Literature

[0004]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0005] Generally, in order to perform tests on a large number of circuit boards and electronic components, it is necessary to sequentially connect each circuit board to the measuring device. Therefore, if the coaxial electrical connector described in Patent Document 1 is used for testing circuit boards and electronic components, the process of attaching and detaching the coaxial electrical connector to the circuit board, that is, tightening and loosening the screws, must be performed sequentially. As a result, the attachment and detachment process becomes complicated, making it difficult to efficiently test multiple circuit boards and electronic components in a short amount of time.

[0006] In view of these circumstances, the present invention aims to provide a probe and probe device that can be easily attached to and detached from a circuit board and that can efficiently perform testing of circuit boards or electronic components. [Means for solving the problem]

[0007] (1) The probe according to the present invention is provided in a probe device that relays a measuring device for measuring the electrical characteristics of a circuit board or the electrical characteristics of electronic components mounted on the circuit board and the circuit board via a cable, and is attached to the end of the cable and connected to the circuit board.

[0008] In such a probe, the present invention provides a signal transmission body electrically conductive to a signal circuit formed on one side surface of the circuit board, a substrate clamping body capable of clamping the circuit board in its thickness direction, and a biasing member that maintains the substrate clamping body in a state of clamping the circuit board, wherein the substrate clamping body has a first clamping piece located on one side of the circuit board and holding the signal transmission body, and a second clamping piece located on the other side of the circuit board, and the biasing member is provided so as to be elastically deformable and spanned between the first clamping piece and the second clamping piece. The first clamping piece and the second clamping piece are biased toward a position for clamping the circuit board, the first clamping piece has a first clamping portion at one end located on the circuit board side that contacts one surface of the circuit board, the second clamping piece has a second clamping portion at one end located on the circuit board side that contacts the other surface of the circuit board, and at least one of the first clamping piece and the second clamping piece has an operating portion at the other end located away from the circuit board that receives an operating force opposite to the biasing force of the biasing member.

[0009] In this invention, when attaching the probe to a circuit board, first, an operating force opposite to the biasing force of the biasing member is applied to the operating part of the probe to separate the first clamping part and the second clamping part far apart, and while maintaining this state, the probe is positioned so that the circuit board is located between the first clamping part and the second clamping part. Here, the first clamping part is located on one side of the circuit board, and the second clamping part is located on the other side of the circuit board. Next, the operating force is released, and the biasing force of the biasing member brings the first clamping part and the second clamping part closer together to clamp the circuit board. In this way, the circuit board is clamped by the first clamping part and the second clamping part under the biasing force of the biasing member, and as a result, the state in which the signal transmission body held by the first clamping piece is in contact with the circuit part of the circuit board is maintained. Furthermore, when removing the probe from the circuit board, the operating force is applied to the operating part of the probe to separate the first clamping part and the second clamping part far apart, thereby releasing the state in which the circuit board is clamped.

[0010] Thus, in this invention, the probe can be easily attached to and detached from the circuit board simply by applying or releasing operating force to the probe's operating part, allowing for efficient testing of the circuit board or the electronic components mounted on the circuit board.

[0011] (2) In the invention of (1), one of the first clamping portion and the second clamping portion may have a projection that is inserted into a through space formed in the circuit board in the thickness direction, and the other clamping portion may have a receiving portion that receives the tip of the projection that protrudes from the through space on the other side of the through space.

[0012] In invention (2), when the circuit board is clamped between the first and second clamping portions of the probe, the projection is inserted into the through-space of the circuit board, and the tip portion protruding from the through-space enters the receiving portion. Therefore, the projection is located within the through-space and within the receiving portion. The movement of the projection in a direction parallel to the circuit board is restricted by the edge of the through-space, thereby positioning the probe relative to the circuit board and maintaining good contact between the signal transmission body and the signal circuit portion of the circuit board.

[0013] (3) In the invention of (2), the projection may be insertable into the through space formed by cutting out the edge of the circuit board. In this way, when attaching or detaching the probe to the circuit board, the projection of the probe can be inserted and removed through the opening of the through space formed in the edge of the circuit board. Therefore, the probe can be attached and detached even when the probe is moved in an oblique direction inclined with respect to the thickness direction of the circuit board, making the attachment and detachment process easier.

[0014] (4) In any of the inventions of (1) to (3), the signal transmission body may have a dielectric held by the first clamping piece and a central conductor held by the dielectric and capable of contacting the signal circuit portion of the circuit board.

[0015] (5) In the invention of (4), the first clamping piece may be made of metal, electrically conductive to the outer conductor of the cable, and in contact with a ground circuit formed on one side of the circuit board. In this way, when a signal current is passed through the central conductor of the signal transmission body and the signal circuit of the circuit board as the transmission path, a return current can be passed through the ground circuit, the first clamping piece, and the outer conductor as the transmission path.

[0016] (6) In the inventions of (4) and (5), the first clamping piece may be connectable to the end of the cable by attaching a mounting member provided at the end of the cable.

[0017] (7) In the inventions of (4) and (5), the first clamping piece may be connectable to the end of the cable by fitting a probe connector provided at the end of the cable.

[0018] (8) In any of the inventions of (1) to (3), the signal transmission body may have a plate-shaped substrate made of an electrical insulating material and a metallic signal transmission path provided on the substrate along the plate surface of the substrate and capable of contacting the signal circuit portion of a circuit board.

[0019] (9) In the invention of (8), the signal transmission body has a metallic ground transmission path provided on the substrate along the surface of the substrate, and the ground transmission path may be able to contact a ground circuit portion formed on one side surface of the circuit board. By making the ground transmission path of the signal transmission body able to contact a ground circuit portion on one side surface of the circuit board, when a signal current is passed through the signal transmission path of the signal transmission body and the signal circuit portion of the circuit board as the transmission path, a return current can be passed through the ground circuit portion and the ground transmission path as the transmission path.

[0020] (10) A probe device according to the present invention comprises the probe according to any one of (1) to (9), a measuring device connecting connector connected to a mating connector provided on the measuring device side, and a cable that relays between the probe and the measuring device connecting connector. Effects of the Invention

[0021] According to the present invention, it is possible to provide a probe and a probe device that can be easily attached to and detached from a circuit board, and that can efficiently perform testing of a circuit board or electronic components. Brief Description of the Drawings

[0022] [Figure 1] It is a perspective view showing the probe device of the first embodiment of the present invention together with a circuit board, showing a state before attachment to the circuit board. [Figure 2] It is a perspective view showing the probe of the probe device in FIG. 1 from obliquely below. [Figure 3] It is a perspective view showing the first holding piece of the probe in FIG. 2 from obliquely below. [Figure 4] It is a cross-sectional view of the probe of FIG. 2 attached to a circuit board, showing a vertical cross-section at the central position in the width direction of the probe. [Figure 5] It is a perspective view showing the probe device in FIG. 1 together with a circuit board, showing a state immediately before attachment to the circuit board. [Figure 6] It is a perspective view showing the probe device in FIG. 1 together with a circuit board, showing a state after attachment to the circuit board. [Figure 7] It is an enlarged cross-sectional view showing a part of the probe device of the second embodiment of the present invention, showing a vertical cross-section at the central position in the width direction of the probe. [Figure 8] It is an enlarged cross-sectional view showing a part of the probe device of the third embodiment of the present invention, showing a vertical cross-section at the central position in the width direction of the probe in a state immediately before the probe and the cable are connected. [Figure 9]This is an enlarged cross-sectional view showing a part of the probe device of the third embodiment of the present invention, and shows a longitudinal cross-section at the central position in the probe width direction when the probe and cable are connected. [Figure 10] This is a perspective view showing a circuit board according to a modified example of the present invention. [Modes for carrying out the invention]

[0023] Embodiments of the present invention will be described below with reference to the attached drawings.

[0024] <First Embodiment> Figure 1 is a perspective view showing a probe device 1 according to a first embodiment of the present invention together with a circuit board P. Only a portion of the circuit board P is shown, and in reality, it extends further in both the X-axis and Y-axis directions. In this embodiment, the X-axis direction is defined as the "front-back direction," with X1 direction being "forward" and X2 direction being "backward." The Y-axis direction is defined as the "probe width direction." The circuit board P is a so-called test board used for performance testing of electronic components (not shown) such as IC chips.

[0025] On the mounting surface of the circuit board P (top surface in Figure 1), as shown in Figure 1, a signal pattern P1 is formed as a signal circuit section extending in the front-to-back direction (X-axis direction) on the mounting surface, and a ground pattern P2 is formed as a ground circuit section extending around the signal pattern P1. Near the front end (X1 side end) of the signal pattern P1, an electronic component (not shown) to be the subject of performance testing is mounted, and near the rear end (X2 side end) (test port) of the signal pattern P1, a probe device 1 is connected (see Figure 6). In addition, on the rear edge of the circuit board P extending in the probe width direction (Y-axis direction), notches P3 are formed as through spaces on both sides of the signal pattern P1 in the probe width direction, by cutting out the rear edge. The notches P3 penetrate the circuit board P in the thickness direction, i.e., in the vertical direction (Z-axis direction), and open to the rear (X2 direction), and function as a positioning section for positioning the probe 2 described later.

[0026] As shown in Figure 1, the probe device 1 includes a probe 2 connected to a circuit board P, a connector 3 for connecting to a measuring device (not shown) provided on the side of a measuring device (not shown) for measuring the electrical characteristics of electronic components, and a coaxial cable 4 (hereinafter referred to as "cable 4") extending in the front-to-back direction (X-axis direction) and relaying the probe 2 and the connector 3. The connector may be provided on the measuring device itself, or on another device connected to the measuring device.

[0027] Probe 2 is a clip-type probe provided at the front end of cable 4. Probe 2 includes a metal substrate clamping body 10 capable of clamping the circuit board P in the vertical direction (Z-axis direction), which is the thickness direction of the board; a metal biasing member 40 that maintains the substrate clamping body 10 in a state of clamping the circuit board P; and a signal transmission body 50 (see Figure 4) held by the substrate clamping body 10 and capable of electrically conducting to the signal pattern P1 of the circuit board P. The substrate clamping body 10 is movable between a closed state (see Figures 1 and 4) and an open state (see Figure 5).

[0028] Figure 2 is a perspective view of the probe 2 of the probe device 1 in Figure 1, taken from a diagonal downward angle. As shown in Figures 1 and 2, the substrate clamping body 10 has a first clamping piece 20 located above (on the Z1 side) the circuit board P and holding the signal transmission body 50, and a second clamping piece 30 located below (on the Z2 side) the circuit board P.

[0029] Figure 3 is a perspective view of the first clamping piece 20 from a diagonal downward angle. As shown in Figures 1 to 3, the first clamping piece 20 is provided with its longitudinal direction being along the front-rear direction. The first clamping piece 20 has a base portion 21 provided at the front, a first clamping portion 25 protruding forward from the base portion 21, a first operating portion 26 provided at the rear, a first connecting portion 27 connecting the base portion 21 and the first operating portion 26, and a supported portion 28 protruding from the lower surface of the first connecting portion 27.

[0030] Figure 4 is a cross-sectional view of the probe 2 attached to the circuit board P, showing a longitudinal section at the center in the probe width direction (Y-axis direction). As shown in Figure 4, the base portion 21 has a holding portion 22 for holding the signal transmission body 50 and the front end of the cable 4, and a plate-shaped first plate portion 24 extending rearward from the rear end of the upper part of the holding portion 22.

[0031] At the lower part of the holding portion 22, a circular hole-shaped housing portion 23 is formed in the central area in the probe width direction, penetrating in the front-to-back direction to accommodate the signal transmission body 50 and the front end of the cable 4. As shown in Figure 4, the housing portion 23 has a front hole portion 23A, an intermediate hole portion 23B, and a rear hole portion 23C that communicate sequentially from the front. Steps are formed on the inner circumferential surface of the front hole portion 23A at multiple positions in the front-to-back direction, and these steps form multiple spaces with different inner diameter dimensions. Of these multiple spaces, the front end hole portion 23A-1, located furthest forward, is designed to accommodate and hold the second dielectric 53, which will be described later. As shown in Figure 4, a front end step portion 23E is formed at the boundary position between the front end hole portion 23A-1 and the space adjacent to it, that is, the space behind the front end hole portion 23A-1 with a smaller diameter than the front end hole portion 23A-1.

[0032] The intermediate hole 23B has a larger diameter than the front hole 23A, and a front step 23D is formed at the boundary between the intermediate hole 23B and the front hole 23A. The rear hole 23C has a larger diameter than the intermediate hole 23B, and a rear step 23E is formed at the boundary between the rear hole 23C and the intermediate hole 23B. The inner circumferential surface of the rear hole 23C has a screw groove (not shown) for attaching the fastening fitting 65, described later, which is provided on the front end of the cable 4. The upper part of the holding part 22 forms a first pressure-receiving part 22F that receives the biasing force from the biasing member 40 from above. The upper surface of the first pressure-receiving part 22F that receives the biasing force is a flat surface perpendicular to the vertical direction.

[0033] As shown in Figure 4, the first plate portion 24 is positioned slightly above the first pressured portion 22F. Furthermore, the upper surface of the base portion 21 forms an inclined surface that slopes upward as it moves towards the rear, in the range that spans both the first pressured portion 22F and the first plate portion 24 in the front-rear direction.

[0034] The first clamping portion 25 is provided protruding from the front surface of the holding portion 22 at both ends in the probe width direction at the lower part of the holding portion 22. In other words, when the probe 2 is viewed from the front, the two first clamping portions 25 are located at approximately the same height as the housing hole portion 23 in the vertical direction and are positioned to sandwich the housing hole portion 23 in the probe width direction. The first clamping portion 25 has a roughly rectangular prism-shaped front piece portion 25A that protrudes forward from the front surface of the holding portion 22, and a roughly cylindrical projection portion 25B (see Figure 3) that protrudes downward from the lower surface of the front piece portion 25A. The outer diameter of the projection portion 25B is slightly larger than the width dimension (dimension in the probe width direction) of the notch P3 of the circuit board P. As shown in Figure 3, the projection portion 25B is divided into two projection pieces by a slit formed at the central position in the probe width direction. These projection pieces are capable of slight elastic deformation in the probe width direction.

[0035] As shown in Figure 1, the first operating portion 26 is formed in the shape of a roughly rectangular plate connected to the rear ends of the two first connecting portions 27, and is designed to receive an upward pressing force (operating force) when the substrate clamping body 10 is operated. The first connecting portions 27 are connected to each side of the base portion 21 in the probe width direction (Y-axis direction) and extend with an upward inclination as they move towards the rear. The space enclosed by the first operating portion 26 and the two first connecting portions 27 is formed as the first housing portion 29 for housing the first biasing piece 41 of the biasing member 40, which will be described later. The roughly front half of the first housing portion 29 is closed from below by the first pressured portion 22F and the first plate portion 24 located between the two first connecting portions 27. The supported portion 28 is provided projecting downward from the lower surface of the intermediate portion of the first connecting portion 27 in the front-rear direction. As shown in Figure 3, the supported portion 28 is approximately semicircular when viewed in the probe width direction, and its outer peripheral surface, which curves downward, is supported by the support portion 34 of the second clamping piece 30 (described later) so as to be rotatable around an axis extending in the probe width direction.

[0036] As shown in Figures 1, 2, and 4, the second clamping piece 30 is a roughly rectangular plate shape with its longitudinal direction in the front-to-back direction, and has a second clamping portion 31 provided at the front, a second operating portion 32 provided at the rear, a second connecting portion 33 connecting the second clamping portion 31 and the second operating portion 32, a support portion 34 protruding from the upper surface of the second connecting portion 33, and a plate-shaped second plate portion 35 extending rearward from the second clamping portion 31.

[0037] The second clamping portion 31 is located in front of the base portion 21 of the first clamping piece 20 and below the first clamping portion 25 of the first clamping piece 20. The second clamping portion 31 is larger than the base portion 21 in the probe width direction and larger than the first clamping portion 25 in the front-rear direction, with the front end of the second clamping portion 31 located in front of the front end of the first clamping portion 25. A receiving portion 31A is formed at the rear of the second clamping portion 31, penetrating the second clamping portion 31 in the vertical direction. The receiving portion 31A is formed in the shape of a square hole with the probe width direction as its longitudinal direction when viewed in the vertical direction, and as will be described later, it is possible to receive the protrusions 25B of the two first clamping portions 25 from above when the substrate clamping body 10 is in the closed position (see Figure 4).

[0038] The second operating section 32 is formed in a roughly rectangular plate shape connected to the rear ends of the two second connecting sections 33, and has a shape similar to the first operating section 26 of the first clamping piece 20 inverted vertically. The second operating section 32 is designed to receive downward pressing force (operating force) when the substrate clamping body 10 is operated. The second connecting section 33 extends in the front-rear direction and connects the rear end of the second clamping section 31 to the front end of the second operating section 32. As shown in Figure 2, the space enclosed by the second clamping section 31, the second operating section 32, and the two second connecting sections 33 is formed as a second housing section 36 that houses the second biasing piece 42 of the biasing member 40, which will be described later.

[0039] The support portion 34 is provided projecting upward from the upper surface of the intermediate portion in the front-rear direction of the second connecting portion 33. The support portion 34 has a support recess 34A (see Figure 1) recessed from the upper surface to accommodate the supported portion 28 of the first clamping piece 20. The inner wall surface of the support recess 34A has a concave curved surface that matches the outer surface of the supported portion 28, and supports the supported portion 28 so that it can rotate. The second plate portion 35 is provided between the two second connecting portions 33 and closes off the approximately front half of the second housing portion 36 from above. As shown in Figure 4, the front part of the second plate portion 35 forms a second pressured portion 35A that receives a biasing force from the biasing member 40 from below. The lower surface of the second plate portion 35 has an inclined surface that slopes downward as it approaches the rear.

[0040] The biasing member 40 is made by bending a metal strip in the thickness direction and has a substantially horizontal U-shape that opens forward as shown in Figure 4, and is provided so as to be elastically deformable by being spanned between the first clamping piece 20 and the second clamping piece 30. The biasing member 40 has a first biasing piece 41 located above, a second biasing piece 42 located below, and two elastic parts 43 that connect the front ends of the first biasing piece 41 and the second biasing piece 42.

[0041] As shown in Figure 4, the first biasing piece 41 extends along the upper surface of the first clamping piece 20, sloping downward as it moves forward, and its front end is bent diagonally forward and upward. The portion of the first biasing piece 41 that protrudes downward at the bent position is formed as the first biasing portion 41A, which biases the upper surface of the first pressured portion 22F from above. As shown in Figure 4, the second biasing piece 42 extends along the lower surface of the second clamping piece 30, sloping upward as it moves forward, and its front end is bent diagonally forward and downward. The portion of the second biasing piece 42 that protrudes upward at the bent position is formed as the second biasing portion 42A, which biases the lower surface of the second pressured portion 35A from below.

[0042] The elastic portion 43 is provided at both ends of the biasing member 40 in the probe width direction, is bent into a roughly horizontal C shape that opens forward, and connects the rear ends of the first biasing portion 41A and the second biasing portion 42A. In this embodiment, since the two elastic portions 43 are spaced apart from each other in the probe width direction, the cable 4 can be inserted between the two elastic portions 43 and attached to the first clamping piece 20.

[0043] The biasing member 40 is configured such that the first biasing piece 41 and the second biasing piece 42 can be displaced vertically, i.e., move closer to or further away from each other, due to the elastic deformation of the elastic portion 43 in the thickness direction. When the biasing member 40 is attached to the substrate clamping body 10, the elastic portion 43 is elastically deformed, and the first biasing piece 41 and the second biasing piece 42 are displaced to widen the distance between them. As a result, the first biasing piece 41 and the second biasing piece 42, by the elastic force (restoring force) of the elastic portion 43, bias the first pressured portion 22F and the second pressured portion 35A of the substrate clamping body 10 with the first biasing portion 41A and the second biasing portion 42A, thereby clamping the substrate clamping body 10 and maintaining the substrate clamping body 10 in a closed state.

[0044] As shown in Figure 4, the signal transmission body 50 is housed in the housing hole 23 of the first clamping piece 20 and held by the holding portion 22. The signal transmission body 50 has a first dielectric 51 housed and held in the intermediate hole 23B, a second dielectric 53 housed and held in the front hole 23A, and a central conductor 52 housed in the front hole 23A and the intermediate hole 23B and held by the first dielectric 51 and the second dielectric 53. The first dielectric 51 and the second dielectric 53 are annular members made of an electrical insulating material such as resin, and are provided in an orientation with the front-rear direction as the axial direction. The first dielectric 51 is located at the rear end position of the intermediate hole 23B. The second dielectric 53 has a smaller diameter than the first dielectric 51 and is located in the front end hole 23A-1. In this embodiment, the first clamping piece 20, which has the housing hole 23 for housing the first dielectric 51, the second dielectric 53, and the central conductor 52, is made of metal. Therefore, the function of a coaxial electrical connector is realized by the first dielectric 51, the second dielectric 53, the central conductor 52, and the first clamping piece 20. In this case, the first clamping piece 20 functions as an outer conductor.

[0045] The central conductor 52 is a metal terminal extending in the front-to-back direction, press-fitted and held in the first dielectric 51 at its intermediate portion in the front-to-back direction, and press-fitted and held in the second dielectric 53 at its front end. The front end of the central conductor 52 protrudes outward from the front opening of the front end hole 23A-1 and is formed as a pin-shaped front contact portion 52A that can contact the signal pattern P1 (see Figure 1) of the circuit board P from above. Furthermore, at the rear end of the central conductor, a plurality of elastic pieces that can elastically deform in the radial direction of the intermediate hole 23B are formed as a rear contact portion 52B that can contact the central conductor 61 of the cable 4, which will be described later.

[0046] When attaching the signal transmission body 50 to the holding part 22, first, the central conductor 52 is inserted from the rear through the central hole of the first dielectric 51, and the central conductor 52 is held by the first dielectric 51. Next, the first dielectric 51 is press-fitted into the housing hole 23 from the front. At this time, the first dielectric 51 is press-fitted until it abuts against the front step 23D. Furthermore, the second dielectric 53 is press-fitted into the front end hole 23A-1 from the front, and the front end portion of the central conductor 52 is inserted from the rear through the central hole of the second dielectric 53, and the central conductor 52 is held by the second dielectric 53. At this time, the second dielectric 53 is press-fitted until it abuts against the front step 23E. As a result, the signal transmission body 50 is held in the holding part 22 while housed in the front hole 23A and the intermediate hole 23B.

[0047] Cable 4 is a coaxial cable having a metal central conductor 61, a dielectric 62 made of an electrical insulating material such as resin that covers and holds the outer surface of the central conductor 61, an outer conductor 63 which is a metal braided shield that covers and holds the outer surface of the dielectric 62, and an outer sheath 64 made of an electrical insulating material such as resin that covers and holds the outer surface of the outer conductor 63. Its front end is inserted from the front into the rear hole 23C of the first clamping piece 20. As shown in Figure 4, at the front end of cable 4, the dielectric 62, outer conductor 63, and outer sheath 64 are partially cut away, so that the outer conductor 63 is exposed from the front end of the outer sheath 64, the dielectric 62 is exposed from the front end of the outer conductor 63, and the central conductor 61 is exposed from the front end of the dielectric 62. Here, the exposed portion of the central conductor 61 forms a contact portion 61A for contacting the central conductor 52 of the signal transmission body 50.

[0048] The front end of the cable 4 is fitted with a metal fastener 65 as an attachment member, a heat-shrinkable tube 66 made of resin (for example, electron beam crosslinked soft flame-retardant polyolefin resin), and a metal cord tube 67. The fastener 65 is a tubular member extending in the front-rear direction and is positioned to straddle the boundary between the exposed portion of the outer conductor 63 and the front end of the outer sheath 64 in the front-rear direction. The front end of the fastener 65 is located slightly behind the front end of the outer conductor 63. The front end of the fastener 65 has threads (not shown) formed on its outer surface, and these threads engage with the thread grooves of the rear hole 23C of the first clamping piece 20, thereby attaching the fastener 65 and, consequently, the cable 4 to the first clamping piece 20. The heat-shrinkable tube 66 is a tubular member extending in the front-rear direction, and is provided so as to straddle the boundary between the rear end of the fastening fitting 65 and the outer sheath 64 in the front-rear direction. It holds the fastening fitting 65 and the outer sheath 64 by being in close contact with the outer circumferential surfaces of both the fastening fitting 65 and the outer sheath 64.

[0049] The cord tube 67 is a tubular member extending in the front-rear direction, and is fitted onto the exposed portion of the outer conductor 63 while being fitted into the front part of the fastening fitting 65. The cord tube 67 is soldered to the outer surface of the outer conductor 63 and is electrically conductive with the outer conductor 63. An overhang 67A is formed at the front end of the cord tube 67, projecting radially outward. The overhang 67A is pressed from the front against the rear stepped portion 23E of the first clamping piece 20 by the fastening fitting 65 when the fastening fitting 65 is screwed into the rear hole 23C of the first clamping piece 20. As a result, the outer conductor 63 of the cable 4 is electrically conductive with the first clamping piece 20 via the cord tube 67.

[0050] As shown in Figure 4, once the fastening fitting 65 and thus the cable 4 have been attached to the first clamping piece 20, the contact portion 61A of the central conductor 61 of the cable 4 enters the intermediate hole 23B of the first clamping piece 20 from the front and makes contact with the multiple rear contact portions 52B of the central conductor 52 with contact pressure, enabling electrical conductivity.

[0051] As shown in Figure 1, a connector 3 for connecting a measuring device is attached to the rear end of the cable 4. The connector 3 for connecting a measuring device is a coaxial electrical connector having an outer conductor, a dielectric housed and held within the outer conductor, and a central conductor held within the dielectric. Since the connector 3 for connecting a measuring device has a configuration similar to that of a general coaxial electrical connector, a detailed explanation of its configuration is omitted here.

[0052] Next, the procedure for using the probe device 1 will be explained. First, the connector 3 for connecting to the measuring device, which is attached to the rear end of the cable 4, is connected to the mating connector (not shown) provided on the measuring device (not shown) side. Next, an operating force is applied to the operating parts of the probe 2 attached to the front end of the cable 4, namely the first operating part 26 of the first clamping piece 20 and the second operating part 32 of the second clamping piece 30 (hereinafter collectively referred to as "operating parts 26, 32" as needed), which is opposite to the biasing force of the biasing member 40, to open the substrate clamping body 10. Specifically, the operating parts 26, 32 are pinched with fingers and pressed against the biasing force of the biasing member 40. As a result, the first operating part 26 is displaced so as to move closer to the second operating part 32, and the first clamping piece 20 is displaced in a lever-like manner with the supported part 28 as the fulcrum. When the first clamping piece 20 is displaced in this manner, as shown in Figure 5, the first clamping portion 25 of the first clamping piece 20 is displaced upward so as to move away from the second clamping portion 31 of the second clamping piece 30, and the substrate clamping body 10 opens. In this open state, a gap larger than the thickness dimension of the circuit board P is formed between the lower end of the projection 25B of the first clamping portion 25 and the receiving portion 31A of the second clamping portion 31 in the vertical direction.

[0053] Next, while keeping the substrate clamping body 10 in the open position, the probe 2 is positioned so that the rear end (the end on the X2 side) of the circuit board P is located between the first clamping portion 25 and the second clamping portion 31. Here, the first clamping portion 25 is located above the circuit board P, and the second clamping portion 31 is located below the circuit board P. Also, at this time, the protrusion 25B of the first clamping portion 25 is located directly above the notch P3 of the circuit board P.

[0054] Next, the operating force is released, and the biasing force of the biasing member 40 brings the first clamping portion 25 and the second clamping portion 31 closer together, clamping the rear end of the circuit board P as shown in Figures 4 and 6. As a result, the front contact portion 52A of the central conductor 52 contacts the signal pattern P1 of the circuit board P from above, making it electrically conductive. Also, the front piece 25A of the first clamping portion 25 contacts (contacts) the ground pattern P2 of the circuit board P from above, making it electrically conductive.

[0055] Furthermore, when the rear end of the circuit board P is clamped by the first clamping portion 25 and the second clamping portion 31, the projection 25B of the first clamping portion 25 is inserted into the notch P3 of the circuit board P from above, and the lower end of the projection 25B protruding downward from the notch P3 enters the receiving portion 31A of the second clamping portion 31 from above (see Figure 4). Therefore, the projection 25B is located inside the notch P3 and the receiving portion 31A. Then, the movement of the projection 25B in the direction parallel to the circuit board P, specifically in the forward direction (X1 direction) and the probe width direction (Y1 direction and Y2 direction), is restricted by the edge of the notch P3, thereby positioning the probe 2 relative to the circuit board P, and maintaining good contact between the front contact portion 52A and the signal pattern P1 and between the front piece portion 25A and the ground pattern P2.

[0056] As previously described, the outer diameter of the projection 25B is slightly larger than the width dimension of the notch P3. In this embodiment, the two projections forming the projection 25B are designed to be slightly elastically deformable in the probe width direction. Therefore, the two projections of the projection 25B are pressed by the inner edge extending in the front-rear direction of the notch P3 and enter the notch P3 in a state of elastic deformation, moving closer to each other in the probe width direction. At this time, the two projections and the inner edge of the notch P3 are in contact with contact pressure, so that the projection 25B and, consequently, the probe 2 are well positioned relative to the circuit board P. In this embodiment, the projection 25B is divided into two projections, but it may be divided into three or more projections. Alternatively, the projection 25B may be formed as an undivided columnar shape (for example, cylindrical), in which case the dimension of the projection in the probe width direction is set to be smaller than the width dimension of the notch P3 of the circuit board P.

[0057] In the usage procedure described above, the projection 25B of the first clamping portion 25 is positioned directly above the notch P3 of the circuit board P and then inserted into the notch P3 from above. However, it is not essential to insert the projection 25B straight into the notch P3 from above. In this embodiment, the notch P3, which serves as a through-space in the circuit board P, opens towards the rear. Therefore, when attaching or detaching the probe 2 to the circuit board P, the projection 25B can be inserted and removed through the rear end opening of the notch P3 in the circuit board P. Thus, even when moving the probe 2 in an oblique direction inclined with respect to the vertical direction, the probe 2 can be attached and detached without interfering with the circuit board P with the projection 25B, making the attachment and detachment process easier.

[0058] In this embodiment, the first clamping piece 20 is made of metal and contacts the cord tube 67 connected to the outer conductor 63 at its rear stepped portion 23E, and contacts the ground pattern P2 of the circuit board P at its front portion 25A. Therefore, when a signal current is passed through the central conductor 61, the central conductor 52, and the signal pattern P1 as the transmission path, a return current can be passed through the ground pattern P2, the first clamping piece 20, the cord tube 67, and the outer conductor 63 as the transmission path.

[0059] In this embodiment, the entire first clamping piece 20 is made of metal, but only a part of it may be made of metal as long as the above-mentioned return current can be passed through it. In that case, for example, only the holding portion 22 and the first clamping portion 25 of the first clamping piece 20 may be made of metal, and the other parts may be made of a material other than metal (for example, an electrical insulating material such as resin). Also, in this embodiment, in addition to the first clamping piece 20, the second clamping piece 30 and the biasing member 40 are made of metal, but it is not essential that the second clamping piece 30 and the biasing member 40 are made of metal. For example, the second clamping piece 30 and the biasing member 40 may be made of an electrical insulating material such as resin.

[0060] Furthermore, when removing the probe 2 from the circuit board P, the above operating force can be applied to the operating parts 26 and 32 of the probe 2 to widely separate the first clamping part 25 and the second clamping part 31, thereby releasing the clamping state on the rear end of the circuit board P. In this way, in this embodiment, the probe 2 can be easily attached to and detached from the circuit board P simply by applying and releasing operating force to the operating parts 26 and 32 of the probe 2, so that electronic components mounted on the circuit board P can be tested efficiently.

[0061] <Second Embodiment> In the first embodiment, the signal transmission body 50 held by the first clamping piece 20 was configured to cooperate with the metal first clamping piece 20 to realize the function of a coaxial electrical connector. However, in the second embodiment, the signal transmission body is composed of a circuit board and a coaxial electrical connector mounted on the circuit board, which is different from the first embodiment. In the probe device according to this embodiment, it is the same as the first embodiment except for the form of the signal transmission body, the form of holding the signal transmission body, and the form of connection between the signal transmission body and the cable. Here, we will mainly explain the differences from the first embodiment, and will omit explanations of parts that are the same as the first embodiment.

[0062] Figure 7 is an enlarged cross-sectional view of a part of the probe device of the second embodiment, showing a longitudinal section at the central position in the probe width direction. In the probe 102 of this embodiment, the signal transmission body 70 has a circuit board 80 held on the lower surface of the holding portion 122 of the first clamping piece 120, and a coaxial electrical connector 90 (hereinafter referred to as "board-side coaxial connector 90") mounted on the lower surface of the circuit board 80. The circuit board 80 has a plate-shaped base material 81 made of an electrically insulating material such as resin, and a metal signal transmission path (not shown) and a metal ground transmission path (not shown) provided along the lower surface of the base material 81. In this embodiment, the signal transmission path is formed as a signal pattern extending in the front-rear direction, and the ground transmission path is formed as a ground pattern extending along the signal transmission path on both sides of the signal transmission path in the probe width direction. As shown in Figure 7, the front end of the circuit board 80 protrudes forward from the holding portion 122.

[0063] Furthermore, the board-side coaxial connector 90 is a male coaxial electrical connector that is soldered to the underside of the circuit board 80 and to which the cable-side coaxial connector 200 (described later) is connected from below. The board-side coaxial connector 90 has a central conductor 91 and an outer conductor 92, with the central conductor 91 connected to the signal transmission path of the circuit board 80 and the outer conductor 92 connected to the ground transmission path of the circuit board 80.

[0064] The front end of the cable 4 is provided with a female coaxial electrical connector 200 (hereinafter referred to as the "cable-side coaxial connector 200") that can be mated and connected to the board-side coaxial connector 90. The cable-side coaxial connector 200 is a so-called right-angle type coaxial electrical connector, in which the connector connection direction is the vertical direction perpendicular to the front-to-back direction, which is the longitudinal direction of the cable 4. The cable-side coaxial connector 200 has a central conductor 201 and an outer conductor 202, with the central conductor 201 connected to the central conductor 61 of the cable 4 and the outer conductor 202 connected to the outer conductor 63 of the cable 4.

[0065] As shown in Figure 7, the cable-side coaxial connector 200 is mated and connected to the board-side coaxial connector 90 from below. In this configuration, the central conductor 201 of the cable-side coaxial connector 200 is connected to the central conductor 91 of the board-side coaxial connector 90, and the outer conductor 202 is connected to the outer conductor 92 of the board-side coaxial connector 90.

[0066] The board-side coaxial connector 90 and the cable-side coaxial connector 200 have a configuration similar to that of a typical coaxial electrical connector, so a detailed explanation of their configuration is omitted here. In this embodiment, the board-side coaxial connector 90 is a male connector and the cable-side coaxial connector 200 is a female connector, but alternatively, the board-side coaxial connector 90 may be a female connector and the cable-side coaxial connector 200 may be a male connector.

[0067] In this embodiment, as shown in Figure 7, when the probe 2 is attached to the circuit board P, the front end of the circuit board 80 is in contact with the circuit board P from above. At this time, the front end of the signal transmission path of the circuit board 80 is in contact with the signal pattern P1 (see Figure 1) of the circuit board P from above, and the front end of the ground transmission path of the signal transmission body 70 is in contact with the ground pattern P2 (see Figure 1) of the circuit board P from above. Therefore, when a signal current is passed through the center conductor 61, center conductor 201, center conductor 91, signal transmission path and signal pattern P1 as the transmission path, a return current can be passed through the ground pattern P2, ground transmission path, outer conductor 92, outer conductor 202, and outer conductor 63 as the transmission path.

[0068] <Third Embodiment> In the first embodiment, the cable 4 was connected to the signal transmission body 50 by screwing a fastening fitting 65 provided at the front end of the cable 4 into the rear hole 23C of the first clamping piece 20. However, in the third embodiment, the cable is connected to the signal transmission body by fitting a coaxial connector provided at the front end of the cable into the rear hole of the first clamping piece, which is different from the first embodiment. In the probe device according to this embodiment, it is the same as the first embodiment except for the shape of the housing hole of the first clamping piece, the shape of the signal transmission body, and the connection method between the signal transmission body and the cable. Here, we will mainly explain the differences from the first embodiment, and parts that are the same as in the first embodiment will be given the same reference numerals as in the first embodiment and will not be described.

[0069] Figures 8 and 9 are enlarged cross-sectional views of a part of the probe device of the third embodiment, showing a longitudinal section at the central position in the probe width direction. Here, Figure 8 shows the state just before the probe 302 and cable 4 are connected, and Figure 9 shows the state after the probe 302 and cable 4 are connected.

[0070] In this embodiment, as shown in Figure 8, the housing hole 323 of the holding portion 322 of the first clamping piece 320 has a front hole 323A, an intermediate hole 323B, and a rear hole 323C formed sequentially from the front, with the inner diameter increasing in the order of rear hole 323C, front hole 323A, and intermediate hole 323B. The cylindrical dielectric 351 of the signal transmission body 350 is press-fitted and held in the front hole 323A. The rear part of the rear hole 323C has a slightly larger inner diameter than the other parts. The inner circumferential surface on the rear end of this rear part protrudes slightly radially inward, and this protruding portion forms a locking portion 323C-1 that can be locked to the ring member 403 of the cable-side coaxial connector 400, which will be described later. The central conductor 352 of the signal transmission body 350 is press-fitted and held in the dielectric 351.

[0071] A cable-side coaxial connector 400, which serves as a probe connection connector, is provided at the front end of the cable 4. The cable-side coaxial connector 400 has a central conductor 401 and an outer conductor 402. The central conductor 401 is connected to the central conductor 61 of the cable 4, and the outer conductor 402 is connected to the outer conductor 63 of the cable 4. As shown in Figure 8, the central conductor 401 has a pin-shaped male contact portion 401A at its front end and a female contact portion 401B with multiple elastic pieces at its rear end. The female contact portion 401B is in contact with the contact portion 61A of the central conductor 61 of the cable 4. In addition, a ring member 403 made of an electrical insulating material such as resin is attached to the outer circumferential surface of the front part of the outer conductor 402.

[0072] When connecting the cable 4 to the first clamping piece 320, the cable-side coaxial connector 400 is inserted from the rear into the rear hole 323C of the first clamping piece 320 and mated into place. At this time, as shown in Figure 9, the ring member 403 of the cable-side coaxial connector 400 is locked in the front-rear direction against the locking portion 323C-1 of the rear hole 323C, thereby preventing the cable-side coaxial connector 400 from unintentionally coming loose to the rear. When the cable-side coaxial connector 400 is mated into place, the central conductor 401 is in contact with the central conductor 352 of the signal transmission body 350, and the outer conductor 402 is in contact with the inner surface of the rear hole 323C.

[0073] To remove the cable 4 from the first clamping piece 320, simply grasp the cable-side coaxial connector 400 with your fingers and pull the cable-side coaxial connector 400 backward with a pulling force greater than the locking force between the ring member 403 and the locking portion 323C-1. As a result, the cable-side coaxial connector 400 can be easily removed from the rear hole 323C. Thus, in this embodiment, the cable 4 can be easily attached to and detached from the first clamping piece 320 simply by inserting and removing the cable-side coaxial connector 400 from the rear hole 323C.

[0074] In the first to third embodiments, the through-space in the circuit board P is formed by a notch P3. However, the shape of the through-space is not limited to this. For example, as shown in Figure 10 as a modified example, the through-space may be formed by a circular hole P4 that penetrates the circuit board P vertically. The inner diameter of this hole P4 is set to be larger than the outer diameter of the projection of the first clamping part. When the through-space is a hole in this way, when attaching the probe to the circuit board P, the projection of the first clamping part of the open board clamping body is positioned directly above the hole P4 in the circuit board P, and then inserted into the hole P4 from above. Note that the shape of the hole is not necessarily circular; for example, it may be square.

[0075] In the first to third embodiments, the probe device is used to test the performance of electronic components such as IC chips mounted on a circuit board. However, it can also be used, for example, to test the performance of the circuit board itself without any electronic components mounted on it. [Explanation of Symbols]

[0076] 1 probe device 2 probes 3. Connector for connecting measuring device 4 Cables 10 Board holding body 20 First clamping piece 25 First clamping part 25B Protrusion 26 First operation section 30 Second clamping piece 31 Second clamping part 31A Reception Department 32 Second operation section 40 Biasing member 50 Signal Transmitter 51 Dielectrics 52 Central conductor 65 Fastening hardware (mounting components) 70 Signal Transmitter 80 Circuit boards 81 Base material 102 probes 120 First clamping piece 302 probe 320 First clamping piece 350 Signal Transmitter 351 Dielectrics 352 Central conductor P Circuit Board P1 Signal pattern (signal circuit section) P2 Ground pattern (ground circuit section) P3 Notch (through space) P4 hole (through space)

Claims

1. A probe is provided in a probe device that relays a measuring device for measuring the electrical characteristics of a circuit board or the electrical characteristics of electronic components mounted on the circuit board to the circuit board via a cable, and is attached to the end of the cable and connected to the circuit board, A signal transmission body that can conduct electricity to a signal circuit formed on one side of the circuit board, A substrate clamping body capable of clamping the circuit board in the thickness direction thereof, The substrate clamping body includes a biasing member that maintains the circuit board in a clamping state, The substrate clamping body has a first clamping piece located on one side of the circuit board and holding the signal transmission body, and a second clamping piece located on the other side of the circuit board. The biasing member is provided so as to be elastically deformable and spans between the first clamping piece and the second clamping piece, and biases the first clamping piece and the second clamping piece toward the position for clamping the circuit board. The first clamping piece has a first clamping portion at one end located on the circuit board side that contacts one surface of the circuit board, The second clamping piece has a second clamping portion at one end located on the circuit board side that contacts the other surface of the circuit board. At least one of the first clamping piece and the second clamping piece has an operating portion at the other end located away from the circuit board for receiving an operating force opposite to the biasing force of the biasing member. One of the first clamping portion and the second clamping portion has a projection that is inserted into a through space formed in the circuit board in the thickness direction, The other clamping portion has a receiving portion that receives the tip of the projection that protrudes from the through space on the other side relative to the through space, The probe is characterized in that the projection is insertable into the through-space formed by cutting out the edge of the circuit board.

2. The probe according to claim 1, wherein the signal transmission body comprises a dielectric held by the first clamping piece and a central conductor held by the dielectric and capable of contacting the signal circuit portion of the circuit board.

3. The probe according to claim 1, wherein the first clamping piece is made of metal, is electrically conductive to the outer conductor of the cable, and is in contact with a ground circuit formed on one side surface of the circuit board.

4. The probe according to claim 1, wherein the first clamping piece is connectable to the end of the cable by attaching a mounting member provided at the end of the cable.

5. The probe according to claim 1, wherein the first clamping piece is connectable to the end of the cable by fitting a probe connection connector provided at the end of the cable.

6. A probe is provided in a probe device that relays a measuring device for measuring the electrical characteristics of a circuit board or the electrical characteristics of electronic components mounted on the circuit board to the circuit board via a cable, and is attached to the end of the cable and connected to the circuit board, A signal transmission body that can conduct electricity to a signal circuit formed on one side of the circuit board, A substrate clamping body capable of clamping the circuit board in the thickness direction thereof, The substrate clamping body includes a biasing member that maintains the circuit board in a clamping state, The substrate clamping body has a first clamping piece located on one side of the circuit board and holding the signal transmission body, and a second clamping piece located on the other side of the circuit board. The biasing member is provided so as to be elastically deformable and spans between the first clamping piece and the second clamping piece, and biases the first clamping piece and the second clamping piece toward the position for clamping the circuit board. The first clamping piece has a first clamping portion at one end located on the circuit board side that contacts one surface of the circuit board, The second clamping piece has a second clamping portion at one end located on the circuit board side that contacts the other surface of the circuit board. At least one of the first clamping piece and the second clamping piece has an operating portion at the other end located away from the circuit board for receiving an operating force opposite to the biasing force of the biasing member. The signal transmission body is characterized by comprising a plate-shaped substrate made of an electrical insulating material and a metal signal transmission path provided on the substrate along the plate surface of the substrate and capable of contacting the signal circuit portion of a circuit board.

7. The signal transmission body has a metal ground transmission path provided on the substrate along the surface of the substrate, The probe according to claim 6, wherein the ground transmission path is capable of contacting a ground circuit portion formed on one side surface of the circuit board.

8. A probe according to claim 1 or claim 6, A connector for connecting to a measuring device, which is connected to a mating connector provided on the measuring device side, A probe device characterized by having a cable that relays the probe and the connector for connecting the measuring device.

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