Electrical connector

Abstract

To provide an electric connector having excellent tensile strength against a pulling operation to a coaxial cable and capable of preventing generation of shavings in an outside crimping member.SOLUTION: The electrical connector 1 includes a contact pin 3 connected to a core wire 110 of a coaxial cable 100, an insulating housing 4 holding the contact pin 3 inside, a tubular outer contact 5 covering the housing 4, an inner crimping member 2 crimped to an outer conductor layer 130 of the coaxial cable 100, and an outer crimping member 6 integrated with the outer contact 5 and crimped to the inner crimping member 2 from outside. The locking projection 64 of the outer crimping member 6 is in contact with the base end surface of the inner crimping member 2 from the base end side.SELECTED DRAWING: Figure 12

Description

[Technical Field]

[0001] The present invention relates generally to electrical connectors, and more particularly to electrical connectors used to provide a coaxial connection with a coaxial cable. [Background technology]

[0002] Combinations of receptacle connectors and plug connectors are widely used to provide electrical connections between electronic devices and other electronic devices via cables. Furthermore, with the recent improvement in the processing power of electronic devices, the amount of data transmitted from one electronic device to another via cables has increased. To transmit large amounts of data in a short period of time, high-frequency signals must be transmitted via cables, creating a need for improved cable signal transmission characteristics, particularly in the high-frequency band. To meet these needs, coaxial cables, which have high signal transmission characteristics in the high-frequency band, are widely used. As is well known, coaxial cables have a coaxial structure consisting of a core wire for transmitting signals, an inner insulating layer that surrounds the core wire, an outer conductor layer (braided layer) that surrounds the inner insulating layer, and an outer insulating layer (sheath) that surrounds the outer conductor layer, all of which are concentrically arranged.

[0003] To provide such a coaxial connection with a coaxial cable, an electrical connector is widely used, which includes a contact pin (inner contact) electrically connected to a core wire of the coaxial cable, an insulating housing covering the contact pin, and an outer contact covering the housing and electrically connected to an outer conductor layer of the coaxial cable. For example, Patent Document 1 discloses an electrical connector 500 shown in FIG. 1. FIG. 1 is a partial cross-sectional view of the electrical connector 1. The electrical connector 500 is connected to an end of a coaxial cable 600 including a core wire 610, an inner insulating layer 620, an outer conductor layer 630, and an outer insulating layer 640.

[0004] The electrical connector 500 includes a metal contact pin 510 crimped onto a core wire 610, a metal inner crimping member 520 crimped onto an outer conductor layer 630, an insulating housing (not shown) that holds the contact pin 510 therein, a metal outer contact 530 that holds the housing therein, and a metal outer crimping member 540 that is formed integrally with the outer contact 530 and crimped onto the inner crimping member 520. The outer crimping member 540 integrated with the outer contact 530 is crimped from the outside onto the inner crimping member 520 that is crimped onto the outer conductor layer 630, thereby attaching the outer contact 530 to the coaxial cable 600.

[0005] As shown in Fig. 2, the outer crimping member 540 includes a tubular portion 550, a pair of opposing end faces 560 formed on the tubular portion 550 and spaced apart from each other by an increasing distance from the distal end to the proximal end, concave-convex structures 570 formed on the pair of opposing end faces 560 so as to complementarily engage with each other, and cantilevered locking pieces 580 formed by cutting and raising the tubular portion 550 inward. Fig. 3 is a partial cross-sectional view illustrating locking of the inner crimping member 520 from the proximal end side by the outer crimping member 540. As shown in Fig. 3, when the electrical connector 500 is assembled, the locking pieces 580 of the outer crimping member 540 face the proximal end surface of the inner crimping member 520. In this state, when a pulling action toward the base end is applied to the coaxial cable 600, the locking piece 580 comes into contact with the base end surface of the inner crimping member 520, preventing the coaxial cable 600 from coming off the base end side from the electrical connector 500. With this configuration, the tensile strength of the electrical connector 500 against a pulling action on the coaxial cable 600 is improved.

[0006] When assembling the electrical connector 500, the coaxial cable 600 to which the inner crimping member 520 is crimped is inserted into the outer crimping member 540 from the base end side. The pair of opposing end surfaces 560 are then closed so that the concave-convex structures 570 of the pair of opposing end surfaces 560 complementarily engage with each other, thereby crimping the outer crimping member 540 to the inner crimping member 520. When the coaxial cable 600 is inserted into the outer crimping member 540 from the base end side, the locking pieces 580 are elastically deformed outward by the inner crimping member 520 and slide on the inner crimping member 520. When the inner crimping member 520 subsequently moves over the locking pieces 580, the locking pieces 580 elastically return to their original position inward. When the locking pieces 580 slide on the inner crimping member 520, the edges of the locking pieces 580 are scraped by the inner crimping member 520, resulting in metal shavings within the outer crimping member 540. Such shavings can cause short circuits in the electrical connector 500, which can reduce the connection reliability of the electrical connector 500.

[0007] Furthermore, when the coaxial cable 600 is inserted into the outer crimping member 540 from the base end side, the locking pieces 580 are elastically deformed outward by the inner crimping member 520. Because the locking pieces 580 have a cantilever shape, when the locking pieces 580 are elastically deformed outward, a strong load is concentrated on the fixed ends of the locking pieces 580, i.e., the connection between the locking pieces 580 and the tubular portion 550, causing permanent deformation (sag) at the connection. As a result, the contact area between the locking pieces 580 and the base end surface of the inner crimping member 520 is reduced, causing a problem in that the tensile strength of the electrical connector 500 becomes insufficient against a pulling action on the coaxial cable 600. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] U.S. Patent Publication No. 11,677,166 Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention has been made in consideration of the above-mentioned conventional problems, and its purpose is to provide an electrical connector that has excellent tensile strength against pulling operations on a coaxial cable and is capable of preventing the generation of shavings within the outer crimping member. [Means for solving the problem]

[0010] Such an object can be achieved by the present invention as defined by the following (1). (1) An electrical connector to be connected to a coaxial cable including a core wire, an inner insulating layer covering the core wire, an outer conductor layer covering the inner insulating layer, and an outer insulating layer covering the outer conductor layer, a contact pin connected to the core wire of the coaxial cable; an insulating housing that holds the contact pins therein; a cylindrical outer contact that covers the housing; an inner crimping member crimped to the outer conductor layer of the coaxial cable; an outer crimping member that is integrated with the outer contact and is crimped from outside onto the inner crimping member; the outer crimping member includes a cylindrical crimping portion that is crimped from the outside to the inner crimping member, and a locking projection that projects inward from an inner circumferential surface of the crimping portion, The electrical connector according to claim 1, wherein the locking projection of the outer crimping member is in contact with the base end surface of the inner crimping member from the base end side. [Effects of the Invention]

[0011] In the electrical connector of the present invention, the locking protrusions of the outer crimping member contact the base-end surface of the inner crimping member from the base-end side, preventing the coaxial cable from coming off the electrical connector toward the base-end side when a pulling action is applied to the coaxial cable. Furthermore, when the coaxial cable crimped by the inner crimping member is inserted into the outer crimping member, the locking protrusions do not permanently deform (set). Therefore, there is no reduction in the contact area between the locking protrusions and the base-end surface of the inner crimping member, and the tensile strength of the electrical connector against a pulling action to the coaxial cable can be improved.

[0012] Furthermore, when the coaxial cable is inserted into the outer crimping member, the locking protrusions of the outer crimping member are not scraped off by the inner crimping member, which prevents the generation of shavings inside the outer crimping member and improves the connection reliability of the electrical connector. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a partial cross-sectional view of a prior art electrical connector. [Figure 2] 2 is a plan view of the outer crimping member of the electrical connector shown in FIG. 1. [Figure 3] 1. FIG. 4 is a partial cross-sectional view illustrating engagement of the inner crimping member from the base end side by the outer crimping member of the electrical connector shown in FIG. [Figure 4] 1 is a perspective view of an electrical connector of the present invention and a coaxial cable to which the electrical connector is connected; [Figure 5] FIG. 5 is an exploded perspective view of the electrical connector and the coaxial cable shown in FIG. 4. [Figure 6] 1 is a cross-sectional view of an electrical connector and a coaxial cable taken along a plane including one core wire of the coaxial cable. [Figure 7] FIG. 6 is a perspective view of the inner crimping member shown in FIG. 5, seen from a different angle. [Figure 8] FIG. 6 is a perspective view of the contact pin shown in FIG. 5, seen from a different angle. [Figure 9] FIG. 6 is a perspective view of the housing shown in FIG. 5, seen from a different angle. [Figure 10] FIG. 10 is a cross-sectional view illustrating how contact pins are held within a housing. [Figure 11] 6 is a perspective view of the outer contact shown in FIG. 5, seen from a different angle. [Figure 12] FIG. 4 is a plan view showing the outer crimping member before being crimped to the inner crimping member. [Figure 13] FIG. 10 is a perspective view illustrating the crimping of an outer crimping member to an inner crimping member. [Figure 14] 13 is a perspective view of a locking protrusion of the outer crimping member shown in FIG. 12. FIG. [Figure 15] 10 is a cross-sectional view illustrating the engagement of the inner crimping member by the engagement protrusion within the outer crimping member. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0014] The electrical connector of the present invention will be described below based on preferred embodiments shown in the accompanying drawings. The drawings referred to below are schematic diagrams prepared for the purpose of explaining the present invention. The dimensions (length, width, thickness, etc.) of the components shown in the drawings do not necessarily reflect the actual dimensions. The same reference numerals are used to designate identical or corresponding components in the drawings. In the following description, the positive Z-axis direction in each drawing will be referred to as the "tip side" or "front side," the negative Z-axis direction will be referred to as the "base side" or "rear side," the positive Y-axis direction will be referred to as the "upper side," the negative Y-axis direction will be referred to as the "lower side," the positive X-axis direction will be referred to as the "front side," and the negative X-axis direction will be referred to as the "rear side." The Z-direction will also be referred to as the "insertion / removal direction of the electrical connector," the Y-direction will be referred to as the "height direction," and the X-direction will be referred to as the "width direction."

[0015] FIG. 4 is a perspective view of an electrical connector of the present invention and a coaxial cable connected to the electrical connector. FIG. 5 is an exploded perspective view of the electrical connector and coaxial cable shown in FIG. 4. FIG. 6 is a cross-sectional view of the electrical connector and the coaxial cable taken along a plane including one of the core wires of the coaxial cable. FIG. 7 is a perspective view of the inner crimping member shown in FIG. 5, seen from a different angle. FIG. 8 is a perspective view of the contact pin shown in FIG. 5, seen from a different angle. FIG. 9 is a perspective view of the housing shown in FIG. 5, seen from a different angle. FIG. 10 is a cross-sectional view illustrating the holding of the contact pin within the housing. FIG. 11 is a perspective view of the outer contact shown in FIG. 5, seen from a different angle. FIG. 12 is a plan view showing the outer crimping member before being crimped to the inner crimping member. FIG. 13 is a perspective view illustrating crimping of the outer crimping member to the inner crimping member. FIG. 14 is a perspective view of a locking protrusion of the outer crimping member shown in FIG. 12. FIG. 15 is a cross-sectional view illustrating the locking of the inner crimping member by the locking protrusion within the outer crimping member.

[0016] 4 and 5, the electrical connector 1 of the present invention is a plug connector that is inserted into and coupled to a mating connector (receptacle connector) mounted on a circuit board provided in any device. When the electrical connector 1 attached to one end of a coaxial cable 100 is inserted into the mating connector and the electrical connector 1 and the mating connector are coupled, an electrical connection is provided between the coaxial cable 100 and the device via the electrical connector 1 and the mating connector.

[0017] The coaxial cable 100 has a concentric structure including a pair of core wires (center conductors) 110, a pair of inner insulating layers 120 that respectively cover the pair of core wires 110 so as to be concentric with the pair of core wires 110, an outer conductor layer (braided layer) 130 that covers the pair of inner insulating layers 120, and an outer insulating layer 140 that further covers the outer conductor layer 130. Although not shown in FIGS. 4 and 5, the base end of the coaxial cable 100 is connected to a device other than the device equipped with the circuit board. Therefore, when the electrical connector 1 and the mating connector are coupled, signal communication between the two devices is possible via the coaxial cable 100. Typically, the device equipped with the circuit board is an ECU (Electronic Control Unit) that controls the operation of the automobile, and the other device to which the base end of the coaxial cable 100 is connected is an in-vehicle device such as an in-vehicle network communication device used for in-vehicle Ethernet or the like, a car navigation system, a car audio system, an in-vehicle camera, an in-vehicle GPS, an in-vehicle TV, or an in-vehicle radio. By coupling the electrical connector 1 with a mating connector, high-speed signal communication between an on-vehicle device and an ECU becomes possible via two core wires (center conductors) 110. In the illustrated embodiment, the electrical connector 1 is a two-pin connector for providing a coaxial connection with a coaxial cable 100 including two core wires 110, but it may also be a multi-pin connector (for example, a four-pin connector (HSD connector)) that provides a coaxial connection with two or more coaxial cables 100. In the following description, the electrical connector 1 will be described as a two-pin connector that provides a coaxial connection with a coaxial cable 100 including two core wires 110.

[0018] As shown in Figure 5, the electrical connector 1 comprises an inner crimping member 2 crimped onto the outer conductor layer 130 of the coaxial cable 100, a contact pin 3 connected to the core wire 110 of the coaxial cable 100, an insulating housing 4 that holds the contact pin 3 internally, a tubular outer contact 5 that covers the housing 4, and an outer crimping member 6 that is integrated with the outer contact 5 and is further crimped from the outside to the inner crimping member 2.

[0019] The inner crimping member 2 is a cylindrical member made of a metal material and is crimped onto the outer conductor layer 130 of the coaxial cable 100. As shown in FIG. 7, the inner crimping member 2 includes a cylindrical support portion 21, a pair of crimping portions 22 located distally of the support portion 21, and a connecting portion 23 connecting the support portion 21 and the pair of crimping portions 22. The support portion 21 has a cylindrical shape and is the portion to which the outer crimping member 6 is crimped from the outside. The distal end surface and proximal end surface of the support portion 21 are flat surfaces perpendicular to the Z direction. As shown in FIG. 6, when the electrical connector 1 is assembled, the inner peripheral surface of the support portion 21 faces the outer conductor layer 130 of the coaxial cable 100 via a gap. The outer crimping member 6 is crimped to the support part 21 from the outside, but since there is a gap between the outer conductor layer 130 and the inner peripheral surface of the support part 21, the pressure for crimping the outer crimping member 6 is received by the support part 21 and is not transmitted to the coaxial cable 100. Therefore, deformation of the core wire 110 of the coaxial cable 100 due to the pressure when the outer crimping member 6 is crimped to the support part 21 is prevented, and thereby deterioration of the signal transmission characteristics of the coaxial cable 100 can be prevented.

[0020] Returning to FIG. 7 , the pair of crimping portions 22 are U-shaped portions that face each other and define an opening 221 through which the coaxial cable 100 is inserted. The distal end surface and proximal end surface of each of the pair of crimping portions 22 are flat surfaces perpendicular to the Z direction. The pair of crimping portions 22 are formed so that the two ends of the U-shape of the pair of crimping portions 22 face inward and face each other with a gap between them. As shown in FIG. 6 , the coaxial cable 100 is inserted through the opening 221. With the coaxial cable 100 inserted through the opening 221, a crimping process is performed in which the two ends of each of the pair of crimping portions 22 are pressed against the outer conductor layer 130 of the coaxial cable 100 using an appropriate tool such as crimping pliers, thereby crimping the pair of crimping portions 22 to the outer conductor layer 130. As a result, the inner crimping member 2 is attached to the outer conductor layer 130. The connecting portion 23 is a plate-like portion that connects the distal end surface of the support portion 21 and the proximal end surfaces of the pair of crimping portions 22. The connecting portion 23 extends obliquely inward from the proximal end side toward the distal end side. The outer surface of the connecting portion 23 is continuous with the outer peripheral surfaces of the support portion 21 and the crimping portions 22.

[0021] 5, each of the pair of contact pins 3 is made of a conductive material such as a copper alloy and is a tubular member connected to the corresponding core wire 110 of the coaxial cable 100. Since the pair of contact pins 3 have the same configuration, one of the contact pins 3 will be described in detail as a representative. As shown in Fig. 8, the contact pin 3 includes a holding portion 31 that holds the core wire 110 of the coaxial cable 100 therein by crimping, a tubular portion 32 that extends from the tip of the holding portion 31 toward the tip side, and a guide portion 33 that is formed at the tip of the tubular portion 32 and that guides the insertion of the corresponding contact pin of the mating connector.

[0022] The holding portion 31 includes a plate-shaped portion 311 extending linearly in the Z direction, and a pair of wall portions 312 extending downward (in the -Y direction) from the plate-shaped portion 311 and pressing the core wire 110 of the coaxial cable 100 onto the plate-shaped portion 311. In the illustrated embodiment, the pair of wall portions 312 are curved so that their tips face the plate-shaped portion 311, but before the contact pin 3 is connected to the core wire 110, the pair of wall portions 312 extend linearly upward from the plate-shaped portion 311 and face each other in parallel. The connection of the contact pin 3 to the core wire 110 is performed in the following procedure. First, the core wire 110 is placed on the plate-shaped portion 311. Next, using an appropriate tool such as crimping pliers, the tip ends of a pair of wall portions 312 extending linearly from plate-like portion 311 are bent toward core wire 110, and crimping is performed to press core wire 110 onto plate-like portion 311. Through this procedure, core wire 110 is firmly held within holding portion 31, and contact pin 3 is connected to core wire 110.

[0023] The cylindrical portion 32 is a portion for receiving a corresponding contact pin of the mating connector. The cylindrical portion 32 is formed to extend linearly from the tip end of the holding portion 31 toward the tip side. The cylindrical portion 32 includes a pair of spring portions 321 that protrude outward from the cylindrical portion 32, and a positioning protrusion 322 that protrudes upward from the outer circumferential surface of the base end of the cylindrical portion 32.

[0024] The pair of spring portions 321 are formed to provide a clicking sensation indicating that the contact pin 3 has been completely pressed into the housing 4 when the contact pin 3 is press-fitted into the housing 4, and to prevent the contact pin 3 from coming off the housing 4. Each of the pair of spring portions 321 has a tapered shape whose height gradually increases from the distal end toward the proximal end. Each of the pair of spring portions 321 is configured to be elastically deformable inward. When the contact pin 3 is press-fitted into the housing 4, the pair of spring portions 321 gradually elastically deform inward along their tapered shape. Thereafter, when the pair of spring portions 321 reach an engagement hole 43 (see FIGS. 9 and 10 ) of the housing 4, which will be described later, they elastically restore to their outward position and engage with the engagement hole 43. The clicking sensation is provided by the elastic restoration of the pair of spring portions 321 as they engage with the engagement hole 43. Furthermore, the pair of spring portions 321 engage with the engagement holes 43, preventing the contact pins 3 from coming off the housing 4.

[0025] Returning to Fig. 8, the positioning protrusion 322 is formed to perform positioning of the contact pin 3 within the housing 4. The positioning protrusion 322 extends upward from the base end of the cylindrical portion 32. As shown in Fig. 6, when the contact pin 3 is completely press-fitted into the housing 4, the positioning protrusion 322 comes into contact with a tapered portion 443 formed on the inner circumferential surface of the housing 4, which will be described later, thereby restricting the press-fitting of the contact pin 3 into the housing 4. With this configuration, the positioning of the contact pin 3 within the housing 4 is performed.

[0026] Returning to FIG. 8 , the guide portion 33 is a portion for guiding the insertion of corresponding contact pins of the mating connector into the tubular portion 32. The guide portion 33 is composed of three plate-shaped portions 331 that protrude from the distal end surface of the tubular portion 32 while being spaced apart from one another. Since all three plate-shaped portions 331 have the same structure, the structure of one plate-shaped portion 331 will be described below as a representative. The plate-shaped portions 331 protrude from the distal end surface of the tubular portion 32 toward the distal end. The base ends of the plate-shaped portions 331 are integrated with the distal end surface of the tubular portion 32, and the distal ends of the plate-shaped portions 331 are free ends. The outer and inner surfaces of the base ends of the plate-shaped portions 331 are continuous with the outer and inner peripheral surfaces of the tubular portion 32. The distal ends of the plate-shaped portions 331 form inclined surfaces that slope outward. The corresponding contact pins of the mating connector slide on the inner surface of the plate-like portion 331, thereby guiding the insertion of the corresponding contact pins of the mating connector into the tubular portion 32. The three plate-like portions 331 are formed at equal angular intervals on the tip surface of the tubular portion 32. The contact pins 3 as described above are press-fitted into the housing 4 and held by the housing 4.

[0027] 5, the housing 4 is a cylindrical member made of an insulating material having elasticity such as a resin material, and has the function of retaining the pair of contact pins 3 therein. As shown in FIGS. 9 and 10, the housing 4 includes a substantially elliptical main body 41, a pair of engagement protrusions 42 protruding outward from the side surface of the main body 41 in the X direction, a pair of engagement holes 43 linearly penetrating the main body 41 in the Y direction, and a pair of through holes 44 formed linearly penetrating the main body 41 in the Z direction. Note that in FIG. 10, components other than the housing 4 and the pair of contact pins 3 are omitted in order to illustrate the internal structure of the housing 4 and how the pair of contact pins 3 are retained within the housing 4.

[0028] The main body 41 is a substantially elliptical cylindrical member flattened in the X direction. The main body 41 is provided with a press-fit portion 411 located on the base end side and press-fitted into the contact portion 62 of the outer crimping member 6, and a tongue-like portion 412 protruding from the press-fit portion 411 toward the tip side. The press-fit portion 411 has an outer shape corresponding to the space defined by the inner circumferential surface of the contact portion 62. The press-fit portion 411 is press-fitted into the contact portion 62 from the tip side, thereby holding the housing 4 by the outer crimping member 6. The tongue-like portion 412 is an elliptical cylindrical portion flattened in the X direction and protruding from the press-fit portion 411 toward the tip side. The outer diameters in the X direction and the Y direction of the tongue-like portion 412 are smaller than the outer diameters in the X direction and the Y direction of the press-fit portion 411, respectively. As shown in Figure 6, when the electrical connector 1 is assembled, the base end portion of the press-fit portion 411 is located within the contact portion 62, and further, the tip end portion of the press-fit portion 411 and the tongue-shaped portion 412 protrude from the contact portion 62 toward the tip end.

[0029] 9, the pair of engaging protrusions 42 are portions that respectively protrude outward from both side surfaces of the press-fit portion 411 in the X direction. The tip end surfaces of the pair of engaging protrusions 42 are inclined surfaces that protrude more from the press-fit portion 411 from the tip end side toward the base end side. On the other hand, the base end surfaces of the pair of engaging protrusions 42 are flat surfaces that are perpendicular to the Z direction. When the press-fit portion 411 is press-fitted into the contact portion 62 of the outer crimping member 6, the pair of engaging protrusions 42 are inserted into the pair of engaging recesses 621 (see FIG. 5) of the contact portion 62, and further, the base end surfaces of the pair of engaging protrusions 42 abut against the bottom surfaces (end surfaces facing the tip side) of the engaging recesses 621, thereby positioning the housing 4 with respect to the outer crimping member 6.

[0030] 9, the pair of engagement holes 43 are rectangular holes that are spaced apart from each other and linearly pass through the press-fit portion 411 in the Y direction. As shown in FIG. 10, the pair of engagement holes 43 communicate with the pair of through holes 44 within the press-fit portion 411. When the contact pin 3 is press-fitted into the through hole 44, the pair of spring portions 321 of the contact pin 3 elastically restore their outward position in the engagement holes 43, providing a clicking sensation. Furthermore, because the pair of spring portions 321 engage with the engagement holes 43, the contact pin 3 is prevented from coming off the through hole 44.

[0031] The pair of through holes 44 are circular openings that are spaced apart from each other and linearly penetrate the main body 41 in the Z direction. As shown in Fig. 10, a pair of contact pins 3 are press-fitted into the pair of through holes 44. Each of the pair of through holes 44 includes a small-diameter portion 441 located at the tip end and communicating with the outside from the tip end surface of the tongue-shaped portion 412, a large-diameter portion 442 located at the base end of the small-diameter portion 441 and communicating with the outside from the base end surface of the press-fit portion 411, and a tapered portion 443 connecting the small-diameter portion 441 and the large-diameter portion 442.

[0032] The small diameter portion 441 is a cylindrical space extending linearly in the Z direction within the main body 41. The diameter of the small diameter portion 441 is approximately equal to the outer diameter of the tubular portion 32 of the contact pin 3. The large diameter portion 442 is a cylindrical space extending linearly from the small diameter portion 441 toward the base end. The diameter of the large diameter portion 442 is larger than the diameter of the small diameter portion 441. As shown in FIG. 10 , the holding portion 31 of the contact pin 3 is located within the large diameter portion 442. The tapered portion 443 is a portion connecting the small diameter portion 441 and the large diameter portion 442. The tapered portion 443 has a tapered shape whose diameter gradually increases from the tip end toward the base end. The diameter of the tip end of the tapered portion 443 is equal to the diameter of the small diameter portion 441, and the diameter of the base end of the tapered portion 443 is equal to the diameter of the large diameter portion 442. As shown in FIG. 6, when the contact pin 3 is press-fitted into the through hole 44, the positioning protrusion 322 of the contact pin 3 abuts against the tapered portion 443, thereby restricting the press-fitting of the contact pin 3 into the through hole 44.

[0033] 5, the outer contact 5 is a tubular member made of a metal material, and functions as an outer conductor layer that covers the housing 4. As shown in Fig. 11, the outer contact 5 covers the contact portion 62 of the outer crimping member 6 from the outside, and further includes a base end portion 51 that is integrated with the contact portion 62, and a protrusion portion 52 that extends from the tip end of the base end portion 51 toward the tip side.

[0034] The base end 51 is an elliptical cylindrical portion that externally covers the contact portion 62 of the outer crimping member 6. The base end 51 has a shape that corresponds to the outer shape of the contact portion 62. As shown in FIG. 6 , the base end of the press-fit portion 411 of the housing 4 and the contact portion 62 are positioned within the base end 51. With the contact portion 62 positioned within the base end 51, a crimping process is performed in which the base end 51 is pressed against the contact portion 62 from the outside, and the base end 51 is crimped to the contact portion 62. Furthermore, the base end 51 and the contact portion 62 are welded together. As a result, the outer contact 5 and the outer crimping member 6 are integrated.

[0035] 11, protrusion 52 is an elliptical cylindrical portion that is flattened in the X direction and protrudes from base end 51 toward the tip end. The diameters of protrusion 52 in the X direction and the Y direction are smaller than the diameters of base end 51 in the X direction and the Y direction, respectively. Protrusion 52 includes a plurality of spring portions 521 formed on the outer peripheral surface of the tip end portion of protrusion 52, and contact portions 522 formed on the tip ends of the plurality of spring portions 521 and that come into contact with outer contacts of a mating connector.

[0036] Each of the multiple spring portions 521 is a plate-like portion formed by cutting out a portion of the outer circumferential surface of the protruding portion 52. The multiple spring portions 521 are formed spaced apart from one another on the outer circumferential surface of the protruding portion 52. The multiple spring portions 521 are formed to reduce the force required to mate the outer contact 5 with the corresponding outer contact of the mating connector. Since the multiple spring portions 521 all have the same structure, the structure of one spring portion 521 will be described below as a representative. The spring portion 521 is integrated with the protruding portion 52 and has one end that functions as a fixed end and the other end that functions as a free end. The other end of the spring portion 521 is curved inward.

[0037] The contact portions 522 are portions that come into contact with corresponding outer contacts of the mating connector. The contact portions 522 are formed on the outer peripheral surface of the other end (free end) of each of the multiple spring portions 521 so as to protrude outward. When the electrical connector 1 and the mating connector are connected, each contact portion 522 comes into contact with a corresponding outer contact of the mating connector. At this time, the multiple spring portions 521 elastically deform inward, thereby reducing the force required to mate the outer contacts 5 with the corresponding outer contacts of the mating connector.

[0038] Returning to Fig. 5, the outer crimping member 6 is a tubular member made of a metal material. The outer crimping member 6 is integrated with the base end portion 51 of the outer contact 5 and is further crimped from the outside onto the inner crimping member 2, thereby being used to attach the outer contact 5 to the coaxial cable 100. Fig. 12 shows the outer crimping member 6 before being crimped onto the support portion 21 of the inner crimping member 2. As shown in Fig. 12, the outer crimping member 6 includes a tubular crimping portion 61 crimped from the outside onto the support portion 21 of the inner crimping member 2, a tubular contact portion 62 located on the tip side of the crimping portion 61, a tubular connecting portion 63 connecting the crimping portion 61 and the contact portion 62, and three locking projections 64 protruding inward from the inner circumferential surface of the crimping portion 61.

[0039] The crimping portion 61 is a cylindrical portion that is crimped from the outside onto the support portion 21 of the inner crimping member 2. The crimping portion 61 includes a pair of opposing end surfaces 611 formed on the upper surface of the crimping portion 61, the distance between which increases from the distal end toward the proximal end, and a concave-convex structure 612 formed on the pair of opposing end surfaces 611 so as to complementarily mesh with each other. The pair of opposing end surfaces 611 define an opening whose width in the X direction increases from the distal end toward the proximal end. As shown in FIG. 13 , the pair of contact pins 3 are crimped onto the pair of core wires 110 of the coaxial cable 100, the housing 4 is press-fitted into the contact portion 62, and further, with the outer contact 5 integrated with the contact portion 62, the coaxial cable 100 to which the inner crimping member 2 is crimped is inserted into the crimping portion 61 from the proximal end. After the pair of contact pins 3 are respectively pressed into the pair of through holes 44 of the housing 4, a crimping process is performed in which the pair of opposing end faces 611 are pressed against the support portion 21 of the inner crimping member 2, and the outer crimping member 6 is crimped to the support portion 21.

[0040] Returning to FIG. 12 , the contact portion 62 is an elliptical cylindrical portion that is flattened in the X direction and located closer to the tip than the crimping portion 61. As shown in FIG. 6 , when the electrical connector 1 is assembled, the contact portion 62 holds the base end portion of the press-fit portion 411 of the housing 4 internally and is further covered from the outside by the base end 51 of the outer contact 5. Therefore, the contact portion 62 is located between the press-fit portion 411 and the base end 51 of the housing 4. As described above, the press-fit portion 411 is press-fitted into the contact portion 62 from the tip side. Furthermore, the contact portion 62 is inserted into the base end 51 of the outer contact 5 from the base end side, and the contact portion 62 and the base end 51 are integrated by crimping the base end 51 and welding the base end 51 and the contact portion 62 together.

[0041] The contact portion 62 has a pair of engaging recesses 621 formed on the tip surface of the contact portion 62. The pair of engaging recesses 621 are rectangular recesses formed on both ends of the tip surface of the contact portion 62 in the X direction, respectively, and extending linearly from the tip side to the base end side. The press-fit portion 411 of the housing 4 is press-fitted into the contact portion 62 from the tip side so that the pair of engaging protrusions 42 of the housing 4 are inserted into the pair of engaging recesses 621, respectively. The pair of engaging protrusions 42 abut against the bottom surfaces (end surfaces facing the tip side) of the pair of engaging recesses 621, respectively, thereby restricting the press-fitting of the press-fit portion 411 into the contact portion 62.

[0042] The connecting portion 63 is a cylindrical portion that connects the crimping portion 61 and the contact portion 62. The connecting portion 63 includes a cylindrical portion 631 that extends linearly in the Z direction, a base-end tapered portion 632 that connects the base end of the cylindrical portion 631 to the tip end of the crimping portion 61, and a tip-end tapered portion 633 that connects the tip end of the cylindrical portion 631 to the base end of the contact portion 62. The cylindrical portion 631 is an elliptical cylindrical member that extends linearly in the Z direction and is flattened in the X direction. The inner diameters of the cylindrical portion 631 in the X direction and the Y direction are smaller than the inner diameters of the crimping portion 61 and the contact portion 62 in the X direction and the Y direction, respectively. Similarly, the outer diameters of the cylindrical portion 631 in the X direction and the Y direction are smaller than the outer diameters of the crimping portion 61 and the contact portion 62 in the X direction and the Y direction, respectively.

[0043] The base-end tapered portion 632 is an elliptical cylindrical portion flattened in the X direction that connects the base end of the tubular portion 631 and the tip end of the crimping portion 61. The base-end tapered portion 632 has a tapered shape in which the inner and outer diameters gradually decrease from the base end side toward the tip end side. The tip-end tapered portion 633 is an elliptical cylindrical portion flattened in the X direction that connects the tip end of the tubular portion 631 and the base end of the contact portion 62. The tip-end tapered portion 633 has a tapered shape in which the inner and outer diameters gradually increase from the base end side toward the tip end side. As shown in FIG. 6 , when the electrical connector 1 is assembled, the inner circumferential surface of the tubular portion 631 covers the inner insulating layer 120 of the coaxial cable 100 from the outside. Furthermore, the pair of crimping portions 22 of the inner crimping member 2 abuts against the inner circumferential surface of the base end side tapered portion 632 , and the inner crimping member 2 is positioned within the outer crimping member 6 .

[0044] Returning to FIG. 12 , each of the three locking protrusions 64 is a circular dome-shaped protrusion that protrudes inward from the inner circumferential surface of the crimping portion 61. The three locking protrusions 64 are formed at equal angular intervals on the inner circumferential surface of the crimping portion 61. Two of the three locking protrusions 64 are formed on the upper portion of the inner circumferential surface of the crimping portion 61, and the remaining one of the three locking protrusions 64 is formed on the lower portion of the inner circumferential surface of the crimping portion 61. Each of the three locking protrusions 64 is formed by pressing a tool such as a pin against the outer circumferential surface of the crimping portion 61 from the outside. Furthermore, since the three locking protrusions 64 are formed by such pressing, recesses corresponding to the three locking protrusions 64 are formed in the pressed portions of the outer circumferential surface of the crimping portion 61. Since the three locking protrusions 64 have the same configuration, the following description will be limited to one locking protrusion 64.

[0045] FIG. 14 shows a locking protrusion 64 formed on the inner peripheral surface of the crimping portion 61. The locking protrusion 64 includes a circular dome portion 641 that protrudes inward from the inner peripheral surface of the crimping portion 61, and annular leg portions 642 that surround the outer edge of the dome portion 641 and connect the dome portion 641 to the inner peripheral surface of the crimping portion 61. The dome portion 641 has a circular dome shape in which the amount of protrusion from the inner peripheral surface of the crimping portion 61 to the inside gradually decreases from the center to the outside. The outer edge of the dome portion 641 is completely surrounded by the leg portions 642. Therefore, there is no discontinuous area, such as a slit or opening, between the outer edge of the dome portion 641 and the leg portions 642, and the outer edge of the dome portion 641 is completely continuous with the leg portions 642.

[0046] The leg portion 642 is an annular portion connecting the dome portion 641 and the inner circumferential surface of the crimping portion 61. The leg portion 642 has a skirt shape that gradually increases inward protrusion from the outside toward the center. The upper end of the leg portion 642 is continuously connected to the outer edge of the dome portion 641, and the lower end of the leg portion 642 is continuously connected to the inner circumferential surface of the crimping portion 61. The entire area of ​​the lower end of the leg portion 642 is continuous with the inner circumferential surface of the crimping portion 61. Therefore, there is no discontinuous area such as a slit or opening between the lower end of the leg portion 642 and the inner circumferential surface of the crimping portion 61, and the entire area of ​​the lower end of the leg portion 642 is continuous with the inner circumferential surface of the crimping portion 61.

[0047] 15 shows the locking of the inner crimping member 2 by the locking protrusions 64 in the crimping portion 61. Note that components other than the inner crimping member 2 and the outer crimping member 6 are omitted from FIG. 15. As shown in FIG. 15, the locking protrusions 64 are formed at positions and heights (amounts of inward protrusion from the inner circumferential surface of the crimping portion 61) such that they come into contact with the base-end surface of the support portion 21 from the base-end side when the crimping portion 61 is crimped from the outside to the support portion 21. Therefore, the locking protrusions 64 are formed on the inner circumferential surface of the crimping portion 61 in order to lock the inner crimping member 2 from the base-end side in the crimping portion 61. In a state in which the crimping portion 61 is crimped from the outside to the support portion 21 of the inner crimping member 2, the three locking protrusions 64 come into contact with the base-end surface of the support portion 21 from the base-end side. With this configuration, even if a pulling action toward the base end is applied to the coaxial cable 100 when the electrical connector 1 is assembled, the three locking protrusions 64 prevent the base end surface of the support portion 21 from shifting toward the base end, thereby preventing the coaxial cable 100 from detaching toward the base end from the electrical connector 1.

[0048] Alternatively, the three locking protrusions 64 may be welded to the base end surface of the support portion 21, and the three locking protrusions 64 may be integrated with the support portion 21. Typically, the three locking protrusions 64 are welded to the base end surface of the support portion 21 by laser welding or spot welding. By integrating the three locking protrusions 64 with the support portion 21 by welding, the tensile strength of the electrical connector 1 against pulling on the coaxial cable 100 can be improved.

[0049] As described above, each locking protrusion 64 has a circular dome shape and therefore does not have an edge portion that comes into contact with the support portion 21 of the inner crimping member 2. Therefore, when the coaxial cable 100 crimped by the inner crimping member 2 is inserted into the outer crimping member 6, each locking protrusion 64 is not scraped off by the support portion 21. This makes it possible to prevent the generation of metal shavings in the outer crimping member 6 and improve the connection reliability of the electrical connector 1.

[0050] Furthermore, when the coaxial cable 100 crimped with the inner crimping member 2 is inserted into the outer crimping member 6, the two upper (+Y direction) locking protrusions 64 of the three locking protrusions 64 do not come into contact with the inner crimping member 2. Therefore, the two upper locking protrusions 64 do not permanently deform (sag). Furthermore, the lower (-Y direction) locking protrusions 64 of the three locking protrusions come into contact with the inner crimping member 2 and elastically deform outward when the coaxial cable 100 is inserted into the outer crimping member 6. However, the load generated when the inner crimping member 2 elastically deforms outward is distributed approximately uniformly over the entire leg portion 642 and does not concentrate at a specific location. Therefore, the lower locking protrusion 64 does not permanently deform (sag). As a result, the contact area between each locking protrusion 64 and the base end surface of the support portion 21 is not reduced, and the tensile strength of the electrical connector 1 against pulling on the coaxial cable 100 can be improved.

[0051] In the illustrated embodiment, the outer crimping member 6 has three locking protrusions 64, but the present invention is not limited to this. The outer crimping member 6 only needs to have at least one locking protrusion 64, and the at least one locking protrusion 64 can lock the base end surface of the support part 21 from the base end side. For example, an embodiment in which the outer crimping member 6 has two or four or more locking protrusions 64 formed at equal angular intervals on the inner circumferential surface of the crimping part 61 is also within the scope of the present invention.

[0052] Furthermore, in the above description, the three locking protrusions 64 are formed on the inner peripheral surface of the crimping portion 61 by inserting the coaxial cable 100 into the outer crimping member 6 and pressing the outer peripheral surface of the crimping portion 61 before crimping the outer crimping member 6 to the inner crimping member 2, but the present invention is not limited to this. When crimping the outer crimping member 6 to the inner crimping member 2, the three locking protrusions 64 do not have to be formed on the inner peripheral surface of the crimping portion 61. In this case, when the outer crimping member 6 is crimped to the inner crimping member 2 or after the outer crimping member 6 is crimped to the inner crimping member 2, the outer peripheral surface of the crimping portion 61 is pressed to form the three locking protrusions 64 on the inner peripheral surface of the crimping portion 61, and the base end surface of the support portion 21 is locked by the three locking protrusions 64 from the base end side.

[0053] The electrical connector 1 including the components described above is attached to the end of the coaxial cable 100 by the following exemplary process. First, the housing 4 is press-fitted from the tip side into the contact portion 62 of the outer crimping member 6. Specifically, the press-fit portion 411 of the housing 4 is press-fitted from the tip side into the contact portion 62 in an orientation such that the pair of engaging projections 42 of the housing 4 are inserted into the pair of engaging recesses 621 of the contact portion 62, respectively. When the pair of engaging projections 42 abut against the bottom surfaces (end surfaces facing the tip side) of the pair of engaging recesses 621, press-fitting of the housing 4 into the outer crimping member 6 is complete.

[0054] Next, the contact portion 62 of the outer crimping member 6 is inserted into the outer contact 5 from the base end side. Specifically, the tongue-shaped portion 412 of the housing 4, which protrudes from the contact portion 62 toward the tip end side, is inserted into the base end portion 51 of the outer contact 5 from the base end side. As shown in FIG. 6 , when the contact portion 62 abuts against the inner circumferential surface of the outer contact 5 from the base end side, the insertion of the contact portion 62 into the outer contact 5 is completed. Next, the base end portion 51 is crimped against the contact portion 62, and the base end portion 51 is crimped to the contact portion 62. Furthermore, the base end portion 51 and the contact portion 62 are welded together. As a result, the outer crimping member 6 is integrated with the outer contact 5. Note that in the above description, the outer crimping member 6 is integrated with the outer contact 5 by crimping and welding, but the present invention is not limited to this. The outer crimping member 6 may be integrated with the outer contact 5 by either crimping or welding.

[0055] Next, the coaxial cable 100 is stripped to expose the pair of core wires 110, the pair of inner insulating layers 120, and the outer conductor layer 130 at the end of the coaxial cable 100 by required lengths. Next, the inner crimping member 2 is attached to the coaxial cable 100. Specifically, the coaxial cable 100 is inserted from the base end side through the support portion 21 and the opening 221 of the inner crimping member 2. With the opening 221 facing the outer conductor layer 130 of the coaxial cable 100, a crimping process is performed in which two ends of each of the pair of crimping portions 22 of the inner crimping member 2 are pressed against the outer conductor layer 130 using an appropriate tool such as crimping pliers, thereby crimping the pair of crimping portions 22 to the outer conductor layer 130.

[0056] Next, the pair of contact pins 3 are crimped to the pair of core wires 110, respectively. Specifically, the pair of core wires 110 exposed by the stripping process are placed on the plate-like portion 311 of the holder 31 of the pair of contact pins 3. As described above, before the contact pins 3 are connected to the core wires 110, the pair of wall portions 312 extend linearly upward from the plate-like portion 311. Using an appropriate tool such as crimping pliers, the tip portions of the pair of wall portions 312 of each contact pin 3 are bent, and the core wires 110 are pressed onto the plate-like portion 311 by crimping, whereby the pair of contact pins 3 are crimped to the pair of core wires 110, respectively.

[0057] Next, the pair of contact pins 3 are inserted into the crimping portion 61 of the outer crimping member 6 from the base end side, and are press-fitted into the pair of through holes 44 of the housing 4, respectively. The pair of spring portions 321 of the pair of contact pins 3 elastically restore their original shape within the engaging holes of the housing 4, the positioning protrusions 322 of the pair of contact pins 3 abut against the tapered portion 443 of the housing 4, and further, the pair of crimping portions 22 of the inner crimping member 2 abut against the inner circumferential surface of the base end tapered portion 632 of the outer crimping member 6, completing the press-fitting of the pair of contact pins 3 into the pair of through holes 44. Figure 13 shows the electrical connector 1 and the coaxial cable 100 in this state.

[0058] Next, the crimping portion 61 of the outer crimping member 6 is subjected to a crimping process in which the pair of opposing end faces 611 is closed and pressed onto the support portion 21 of the inner crimping member 2, and the crimping portion 61 is crimped onto the support portion 21 from the outside. In this state, the pair of concave-convex structures 612 formed on the pair of opposing end faces 611 complementarily engage and lock. As a result, the outer contact 5 is attached to the coaxial cable 100. If the three locking protrusions 64 are not formed on the inner circumferential surface of the crimping portion 61 when the crimping portion 61 is crimped onto the support portion 21, then the outer circumferential surface of the crimping portion 61 is press-formed when or after the crimping portion 61 is crimped onto the support portion 21, so that the three locking protrusions 64 are formed on the inner circumferential surface of the crimping portion 61. As shown in FIG. 15, in this state, the three locking projections 64 of the outer crimping member 6 are in contact with the base end surface of the support portion 21 of the inner crimping member 2 from the base end side.

[0059] Next, laser welding or spot welding is performed between the three locking protrusions 64 and the base end surface of the support portion 21, and the three locking protrusions 64 are welded to the base end surface of the support portion 21. This integrates the three locking protrusions 64 with the base end surface of the support portion 21. Through the above steps, the electrical connector 1 is attached to the end of the coaxial cable 100.

[0060] While the electrical connectors of the present invention have been described above based on the illustrated embodiments, the present invention is not limited to these. Each component of the present invention can be replaced with any component that can perform the same function, or any component can be added to each component of the present invention.

[0061] Those skilled in the art and technology to which the present invention pertains will be able to modify the configuration of the electrical connector of the present invention as described without significantly departing from the principles, concepts, and scope of the present invention, and electrical connectors having modified configurations are also within the scope of the present invention.

[0062] Furthermore, the numbers and types of components of the electrical connector shown in the drawings are merely examples for the purpose of explanation, and the present invention is not necessarily limited thereto. Any addition or combination of any component, or any deletion of any component, is also within the scope of the present invention, as long as it does not deviate from the principles and intent of the present invention. [Explanation of symbols]

[0063] 1...electrical connector 2...inner crimping member 21...support portion 22...crimping portion 221...opening 23...connecting portion 3...contact pin 31...holding portion 311...plate-shaped portion 312...wall portion 32...cylindrical portion 321...spring portion 322...positioning protrusion 33...guide portion 331...plate-shaped portion 4...housing 41...main body portion 411...press-fit portion 412...tongue-shaped portion 42...engaging protrusion 43...engaging hole 44...through hole 441...small diameter portion 442...large diameter portion 443...tapered portion 5...outer contact 51...base end portion 52...projecting portion 521...spring portion 522...contact portion 6...outer crimping member 61...crimping portion 611...opposing end surface 612...concave-convex structure 62...contact portion 621...engaging recess 63...Connection portion 631...Cylindrical portion 632...Base end tapered portion 633...Tip end tapered portion 64...Latching protrusion 641...Dome portion 642...Leg portion 100...Coaxial cable 110...Core wire 120...Inner insulating layer 130...Outer conductor layer 140...Outer insulating layer 500...Electrical connector 510...Contact pin 520...Inner crimping member 530...Outer contact 540...Outer crimping member 550...Cylindrical portion 560...Opposite end surface 570...Uneven structure 580...Latching piece 600...Coaxial cable 610...Core wire 620...Inner insulating layer 630...Outer conductor layer 640...Outer insulating layer

Claims

1. An electrical connector to be connected to a coaxial cable including a core wire, an inner insulating layer covering the core wire, an outer conductor layer covering the inner insulating layer, and an outer insulating layer covering the outer conductor layer, a contact pin connected to the core wire of the coaxial cable; an insulating housing that holds the contact pins therein; a cylindrical outer contact that covers the housing; an inner crimping member crimped to the outer conductor layer of the coaxial cable; an outer crimping member that is integrated with the outer contact and is crimped from outside onto the inner crimping member; the outer crimping member includes a cylindrical crimping portion that is crimped from the outside to the inner crimping member, and a locking projection that projects inward from an inner circumferential surface of the crimping portion, The electrical connector according to claim 1, wherein the locking projection of the outer crimping member is in contact with the base end surface of the inner crimping member from the base end side.

2. 2. The electrical connector according to claim 1, wherein the locking projection of the outer crimping member comprises a dome portion that protrudes inward from the inner circumferential surface of the crimping portion, and a circular leg portion that surrounds the outer edge of the dome portion and connects the dome portion and the inner circumferential surface of the crimping portion.

3. the leg portion of the locking projection of the outer crimping member has an upper end portion continuous with the outer edge of the dome portion and a lower end portion continuous with the inner circumferential surface of the crimping portion, 3. The electrical connector according to claim 2, wherein the entire area of ​​the lower end of each of the legs is continuous with the inner circumferential surface of the crimping portion.

4. 2. The electrical connector according to claim 1, wherein the locking projection of the outer crimp member is welded to the base end surface of the inner crimp member.

5. the inner crimping member includes a crimping portion that is crimped to the outer conductor layer of the coaxial cable, and a tubular support portion that is located closer to a base end than the crimping portion and to which the crimping portion of the outer crimping member is crimped from the outside, 2. The electrical connector according to claim 1, wherein the locking projection of the outer crimping member contacts a base end surface of the support portion of the inner crimping member.

6. the outer crimping member accommodates the housing therein, and further comprises a cylindrical contact portion accommodated inside the outer contact, and a cylindrical connecting portion connecting the crimping portion and the contact portion, 2. The electrical connector according to claim 1, wherein the outer contact is crimped or welded to the contact portion of the outer crimp member, and the outer contact and the outer crimp member are integrated.

7. 7. The electrical connector according to claim 6, wherein the connection portion of the outer crimping member covers the inner insulating layer of the coaxial cable from the outside.

8. 2. The electrical connector according to claim 1, wherein each of the inner crimp member and the outer crimp member is formed from a metallic material.

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