A high-frequency coaxial connector, including male connector portions and female connector portions. Each connector portion includes a grounding terminal. When connector portions are mated, each male connector portion grounding terminal is within the grounding terminal of an associated female connector portion. The grounding terminal of each male connector portion has a radially protruding section at its distal end. The distal end of at least one grounding terminal of each mateable associated male connector portion and female connector portion has slits therein, permitting the radially protruding sections of the male connector portion grounding terminals to alter the diameter of the distal ends of the slitted grounding terminals as the male connector portion grounding terminals are inserted into the female connector portion grounding terminals during mating of connector portions, assuring contact between the grounding terminals of the mated connector portions so as to provide electrical continuity between the grounding terminals.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a multipole high-frequency coaxial connector mainly suitable for connection to an antenna.

2. Description of the Related Art

Concerning high-frequency connectors, 1.5 GHz band-compatible connectors for coaxial cables are conventionally known as connectors for AM/FM band frequencies and television band frequencies. As their types, unipole (1-pin) connectors and multipole (multi-pin) connectors such as the one shown in a related art patent document are known.

In digital communication which will become widespread in the future, a frequency band of 3 GHz to 4 GHz which is higher than ordinary AM/FM analog radio or television frequency bands is used. This applies not only to consumer communications equipment but also to vehicle-mounted antennas. For example, satellite antennas, mobile telephone antennas, and GPS antennas are also used at the high-frequency band of 3 GHz to 4 GHz.

In the connection of such a digital antenna, a connector compatible with a high frequency band is indispensable. Moreover, a satellite antenna requires two-pole outputs of a ground wave and a satellite wave, and a mobile telephone antenna requires two-pole outputs of personal mobile communication and a digital cellular or analog cellular telephone system. However, it has been impossible for the related art technique to be used in a compatible manner.

As a countermeasure for this problem, as shown inFIG. 10, coaxial cables connected to each antenna are respectively connected to 1-pin type unipole connectors C and D, which are in turn connected to an unillustrated pair of unipole connectors. However, there have been problems in that a wiring of the system becomes complex, that a connection operation involves time and trouble, and that a cost becomes high.

SUMMARY OF THE INVENTION

The present invention has been devised to overcome the above-described problems, and its object is to provide a multipole and compact high-frequency coaxial connector which is suitable as a coaxial connector for interfacing a high-frequency antenna system of 3 GHz to 4 GHz, such as a satellite antenna, a mobile telephone antenna and an ETC (electronic toll collection) antenna.

To attain the above-described object, the multipole high-frequency coaxial connector in accordance with the invention includes: a male section and a female section that connect a plurality of coaxial cables concurrently; and a housing made of synthetic resin that is provided in the male section and the female section respectively, wherein each coaxial cable is provided with a coaxial cable terminal respectively on one end thereof that is inserted parallel in the housing, each coaxial cable terminal includes: a hot terminal fixed to cover a central conductor projecting from each coaxial cable; a tubular insulator fixed to cover the hot terminal; and a grounding terminal that is provided on an outer periphery of the insulator and connected to a terminal fixed to an outer conductor of each coaxial cable, and the grounding terminals of each coaxial cable of the male section and the female section are configured to be engaged with each other in a case where the male section and the female section are engaged with each other.

In a high-frequency connector for a frequency band of 3 GHz to 4 GHz, a multipole connector can be realized with a relatively simple single housing structure. For instance, in a case of satellite use, two-pole outputs of a ground wave and a satellite wave can be realized, and in a case of mobile telephone use, two-pole outputs of personal mobile communication and a digital cellular or analog cellular telephone system can be realized. Furthermore, 3-pole outputs of GPS, ETC, and VICS can be realized. Thus it is possible to obtain an outstanding advantage in that a plurality of high-frequency interfaces in digital-compatible high-frequency antenna signal communication, which will become widespread in the future, can be configured by a single connector.

Moreover, as compared with a case where a plurality of unipole coaxial connectors is used, the housing can be used in common. Further, since the tubular insulator is fitted over the hot terminal, and the grounding terminal is fitted over it, protection can be provided against signal interference between the terminals in the parallel state. Since the distance between adjacent ones of the terminals can be made short, the size of the connector can be made compact. Furthermore, in terms of use, an advantage can be obtained in that the connecting operation of the connector on the vehicle side is facilitated, making it possible to reduce the operating time.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The grounding terminals of the male section and the female section are formed of plates of a circular cross section, and one of the grounding terminals has a plurality of slits in a circumference thereof.

According to this construction, although a plurality of poles are provided, the size of the connector housing can be made compact, and contact at the time of engagement can be made satisfactory.

Referring now to the accompanying drawings, a description will be given of an embodiment of the invention.

FIGS. 1 to 9illustrate an embodiment of a high-frequency coaxial connector in accordance with the invention, in which reference character1A denotes a female section, and1B denotes a male section.

Reference character2A denotes a synthetic resin-made housing for the female section1A, and2B denotes a synthetic resin-made housing for the male section1B.

Reference numeral3denotes one of a plurality of (in this embodiment, two) coaxial cables for a frequency band of 3 GHz to 4 GHz. In this coaxial cable3, a central conductor (core)30is enclosed with an insulating/cushioning31such as polyethylene, a braided outer conductor (shield)32is provided around its outer periphery, and a resin cladding33is further provided on its outer side. Terminations of the coaxial cables3are respectively inserted in the housings2A and2B in a parallel state.

Special connection parts3A and3B, in which a hot terminal, an insulator, and a grounding terminal are combined, are provided at the terminations of the coaxial cables3, as shown inFIGS. 3,7A,7B,6, and8.

To describe the connection part3A of the coaxial cable3of the female section1A, a hot terminal4is fitted over and secured to the central conductor30projecting from the termination of each coaxial cable3. The hot terminal4is closely fitted and inserted in a synthetic resin-made insulator5which is tubular as a whole. As shown inFIG. 3, the hot terminal4has a recessed portion40at its intermediate portion, and a three-way cut resiliently engaging piece50formed in the insulator5is engaged therewith to obtain positioning and fixation.

A hollow cylindrical grounding terminal6made of aluminum or the like is fitted over and fixed to the insulator5. A reduced-diameter portion51is formed on an outer periphery of a front half portion of the insulator5so as to form an annular gap8with respect to an inner periphery of the front portion of the grounding terminal for the entry of the male section-side grounding terminal.

As shown inFIG. 7A, a three-way cut resiliently engaging piece60is formed in a portion of the grounding terminal6, and is engaged with a stepped portion52of the insulator5to obtain positioning and fixation.

The grounding terminal6has an axially extending portion61formed continuously on a portion of its circumference, and a crimping terminal portion7is formed at an end of the axially extending portion61. The crimping terminal portion7is crimped by surrounding the outer conductor32of the coaxial cable3.

To describe the connection part3B of the coaxial cable3of the male section1B, a hot terminal4′ to be inserted into a hole of the female section-side hot terminal4is fitted over and secured to the central conductor30projecting from the termination of the coaxial cable3. Further, the hot terminal4′ is closely fitted and inserted in a synthetic resin-made insulator5′ which is cylindrical as a whole. The hot terminal4′ has the recessed portion40at its intermediate portion, and the three-way cut resiliently engaging piece50formed in the insulator5′ is engaged therewith to obtain positioning and fixation.

A cylindrical grounding terminal6′ is fitted over and fixed to the insulator5′. This grounding terminal6′ has a smaller outside diameter than the grounding terminal6on the female section side. A plurality of slits64are provided in the circumference of the grounding terminal6′ over a predetermined range from its distal end, and a radially protruding potion65is provided in the vicinity of the distal end.

A distal end face of the insulator5′ is located in the rear of the slits64so as to abut against or to be in close proximity to a distal end face of the mating insulator5when the grounding terminals6an6′ are engaged with each other.

The grounding terminal6′ has the axially extending portion61formed continuously on a portion of its circumference, and the crimping terminal portion7is formed at an end of the axially extending portion61. The crimping terminal portion7is crimped by surrounding the outer conductor32of the coaxial cable3.

It should be noted that the grounding terminals6and6′ including the crimping terminal portions7are formed of a plate material. The grounding terminals6and6′ are each formed such that the plate is wrapped around each of the insulators5and5′, and in this state its circumferential ends are soldered together, or coupled by fitting together a projection67and a recessed portion68which are dovetail-shaped, as shown inFIG. 7B. The male-side grounding terminal6′ is provided in advance with the slits at predetermined intervals in its distal region in the state of the plate.

The pair of connection parts3A of the coaxial cables3in the female section1A are respectively inserted in a pair of parallel through hole portions20of a substantially circular cross section formed in the housing2A, such that the respective grounding terminal6reaches the vicinity of the opening in the housing2A. The through hole portions20are not limited to the case in which their cross sections have closed contours.

Further, as shown inFIG. 3, a rear end face of a main portion of each grounding terminal6abuts against an end21in the housing2A, and a fixing bar9inserted in the housing abuts against a bulging projection66formed on a portion of the circumference of the grounding terminal6, thereby fixing the respective grounding terminal6in the housing2A.

The housing2A is provided with a partition wall22to form the pair of through hole portions20of the respective connection parts3A.

In addition, as shown inFIG. 6, the housing2B has a pair of fitting cavities23for the housing2A in such a manner as to extend over a predetermined range from its opening.

The pair of parallel through hole portions20of the substantially circular cross section is provided continuing from the respective fitting cavities23. The pair of grounding terminals6′ are respectively inserted in these through hole portions20such that the slits64in their distal regions are located in the respective fitting cavities23.

Further, as shown inFIG. 6, a rear end face of the main portion of each grounding terminal6′ abuts against the end portion21in the housing2B, and the fixing bar9inserted in the housing abuts against the bulging projection66formed on a portion of the circumference of the grounding terminal6′, thereby fixing the respective grounding terminal6′ in the housing2B.

The housing2B is provided with the partition wall22to form the pair of through hole portions20of the respective connection parts3B.

It should be noted that the invention is not limited to the embodiment. For instance, the following arrangements may alternatively be adopted.1) Although a 2-pole connector is adopted in the embodiment by using two coaxial cables, 3-pole, 4-pole, or other connectors may be adopted by using 3, 4, or other number of coaxial cables.2) The slits64may be provided in the grounding terminal6, and the grounding terminal6′ may be formed in a tubular shape.

In the invention, the female sections1A or the male sections1B are connected to coaxial cables from the antenna, the male sections1B or the female sections1A are connected to coaxial cables on an apparatus side, and the housings2A and2B are engaged with each other. As a result, the plurality of sets of connection parts3A and3B which are in a parallel relationship in the housings2A and2B are respectively connected, as shown inFIG. 9, and simultaneous connection of 2 or more poles can be obtained. Accordingly, the connecting operation can be performed only once, and the arrangement is made simple as compared with the case where the unipole connectors are connected one by one.

When the housing2A of the female section1A is engaged in the fitting cavities of the male section1B, each grounding terminal6′ of the male section1B enters the annular gap8in the female section1A. However, since the slits64are provided, the grounding terminal6′ is fitted in the grounding terminal6in the female section1A while undergoing a reduction in its diameter, and the radially protruding potion65is brought into close contact due to the enlargement of its diameter caused by restoration. Accordingly, the state of connection is reliable, and an appropriate grounding can be obtained.

At the same time, since the insulator5of the female section1A and the insulator5′ of the male section1B are substantially abutted against each other inside each of the grounding terminals6and6′, reliable insulation is provided. In this state, the hot terminal4′ of the male section1B is inserted in the hot terminal4of the female section1A inside the grounding terminals6and6′. Accordingly, it is possible to reliably receive or transmit a high-frequency signal.

If high-frequency signal systems are located in close proximity to each other, mutual interference can be induced, thereby frequently resulting in an antenna signal performance loss. For this reason, the higher the frequency, the more it is necessary to space apart the distance between adjacent ones of the multipole terminals inside the connector. In that case, the size of the connector itself becomes large, and it becomes difficult to render the multipole connector compact.

Therefore, in the invention, the insulators5and5′ are provided in the grounding terminals6and6′ of the connection parts3A and3B which are in the parallel relationship, thereby providing protection from signal interference between the hot terminals4and4′ which are in the parallel relationship. For this reason, the housing can be made compact by making the terminal pitch small.