Multi-coaxial connector having a metallic block connected in common to outer conductors of a plurality of coaxial cables

Information

  • Patent Grant
  • 6257927
  • Patent Number
    6,257,927
  • Date Filed
    Wednesday, November 3, 1999
    25 years ago
  • Date Issued
    Tuesday, July 10, 2001
    23 years ago
Abstract
A multi-coaxial connector comprises a metallic die-cast block having a plurality of through-holes, a plurality of L-shaped contacts each having foot and leg portions, and a plurality of insulator sleeves. The through-holes hold the foot portions of the L-shaped contacts on the inside circumferences thereof, via the insulator sleeves, respectively. The L-shaped contacts serve as inner coaxial conductors, while the metallic block serves as a common outer coaxial conductor for the inner coaxial conductors. The connector further comprises an insulator housing which has an open rear end and additional through-holes corresponding to the through-holes. Such insulator housing accommodates the front end of the metallic block inserted thereinto through the open end, so as to serve as a cap of the metallic block.
Description




BACKGROUND OF THE INVENTION




This invention relates to a multi-coaxial connector for electrically connecting a plurality of coaxial cables to a connecting object such as a printed circuit board, and, in particular, to such a multi-coaxial connector which is fixed on and connected to the connecting object and which is removably coupled with a mating connector fixedly connected to a plurality of coaxial cables.




A coaxial cable is known in the prior art and is advantageously used for transmitting a high frequency signal. The coaxial cable comprises an inner conductor, an outer conductor surrounding the inner conductor through an insulator layer, and an outer jacket on the outer conductor. The inner conductor is used for transmitting electrical signal and the outer conductor serves for electromagnetically shielding the inner conductor. Thus, the use of the coaxial cable can avoid electromagnetic interference such as invading noise into the inner conductor from the outside and undesired radiation from the inner conductor due to the high-frequency signal flowing therethrough.




A coaxial connector is also known in the prior art for electrically connecting a coaxial cable with another coaxial cable. The coaxial connector comprises a plug unit and a receptacle unit which mutually mate. Each of the plug unit and the receptacle unit includes an inner contact element and an outer contact element connected to the inner conductor and the outer conductor, respectively, of the corresponding one of the both coaxial cables.




In order to connecting a plurality of coaxial cables with a connecting object such as a printed circuit board, a multi-coaxial connector is known in the prior art. The conventional connector includes a plurality of inner and outer contact pairs. Each of the inner and outer contact pairs comprises an inner contact element and an outer contact element surrounding, and insulated from, the inner contact element. Each of the inner and outer contact elements has a terminal portion which is fixed and connected, or soldered to a corresponding conductor, for example, a pad on the printed circuit board. A mating connector to be coupled with this multi-coaxial connector also includes a plurality of inner and outer contact pairs which are fixedly and electrically connected with inner and outer conductor pairs of the plurality of coaxial cables, respectively.




The conventional connector is mounted on the printed circuit board and the mating connector is connected and fixed to the plurality of coaxial cables. Then, the mating connector is coupled to the conventional connector, so that the plurality of coaxial cables are electrically connected to the printed circuit board.




As example of such conventional multi-coaxial connector is disclosed in U.S. Pat. No. Re. 36,065.




However, the conventional connector is composed of many parts, and requires a complicate manufacturing process, owing to the structure and the number of the parts.




SUMMARY OF THE INVENTION




This invention therefore provides the multi-coaxial connector which consists of less parts and can be readily manufactured, in comparison with the conventional connector.




According to one aspect of the present invention, a multi-coaxial connector comprises a metallic block, a plurality of contact elements, and a plurality of insulator sleeves.




The metallic block has a front end surface and a rear end surface, and is formed with a plurality of first through-holes extending in parallel with each other between the front end and the rear end of the metallic block. Such metallic block may be a die-cast metallic block.




The contact elements are disposed in the first through-holes, respectively. Each of the contact elements comprises a support portion having opposite front and rear ends, a contact portion extending from the front end of the support portion, and a terminal portion extending from the rear end of the support portion.




Each of the insulator sleeves is fitted on the support portion of each of the contact elements, while being fitted in each of the first through-holes. And thereby, the contact elements are stationarily supported in the first through-holes, respectively, in a state that the contact elements are electrically insulated from the metallic block. Thus, the contact elements and the metallic block function as coaxial inner conductors and a coaxial common outer conductor, respectively.




With this structure, the number of parts comprising the multi-coaxial connector decreases, because the metallic block is common to all of the contact elements and functions as a coaxial common outer conductor. Beside that, such connector is manufactured, by fitting the insulator sleeve on the support portion of each contact element and then inserting the contact element together with each sleeve into each first through hole of the metallic block. That is, manufacturing process becomes easy, according to one aspect of the present invention.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of a conventional connector, a part of which is shown broken away;





FIG. 2

is a cross-sectional view of a conventional connector illustrated in

FIG. 1

;





FIG. 3

is a perspective and enlarged view for use illustrating L-shaped casings as outer conductors in

FIGS. 1 and 2

;





FIG. 4

is a rear perspective view illustrating a multi-coaxial connector according to a preferred embodiment of this invention, being mounted onto a circuit board;





FIG. 5

is a disassembled perspective view of the connector illustrated in

FIG. 6

;





FIG. 6

is a cross-sectional view of a mating connector of the connector illustrated in

FIG. 4

;





FIG. 7

is a front view of the connector illustrated in

FIG. 4

;





FIG. 8

is a partially exploded plane view of the connector illustrated in

FIG. 4

;





FIG. 9

is a cross-sectional view of the connector illustrated in

FIG. 4

;





FIG. 10

is a cross-sectional view of an insulator housing of the connector illustrated in

FIG. 4

; and





FIG. 11

is a partially enlarged cross-sectional view for use in describing of manufacturing process of the connector illustrated in FIG.


4


.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




Prior to description of embodiments of this invention, brief description of a conventional one of multi-coaxial connectors will at first be made for a better understanding of this invention.




Referring to

FIGS. 1 through 3

, the conventional connector


1


is mounted on a printed circuit board


2


and comprises a housing


11


, a portion of which is shown broken away. In the illustrated connector


1


, the housing


11


carries two rows of three coaxial contact elements


12


. Herein, the connector


1


is to be removably coupled with a mating connector, which also has two rows of three inner and outer coaxial conductor, although not shown.




Each of coaxial contact elements


12


comprises a tubular inner contact part


14


shown in broken lines, a cylindrical outer contact part


13


surrounding the tubular inner contact part


14


. The cylindrical outer contact parts


13


has radially projecting lips


28


for locking the coaxial contact elements


12


to the housing


11


, and are connected to L-shaped casings


22


,


23


. The tubular inner contact parts


14


are connected to L-shaped contact elements


26


.




The L-shaped casings


22


and


23


are manufactured from sheet metal and are connected to the outer contact part


13


by means of spot welds which are diagrammatically indicated by open circles


29


in

FIGS. 1 and 2

. The L-shaped casings


22


and


23


are each provided with two pin-type connecting ends


24


for connecting to the printed circuit board


2


. One end of the L-shaped contact element


26


is also connected to the printed circuit board


2


. Thus, the conventional connector


1


can establish the connection a plurality of the coaxial cables and the printed circuit board


2


, by being mounted on the board


2


and by being connected to the mating connector.




However, the conventional connector requires a pair of inner and outer contact parts


14


,


15


of the coaxial contact elements


12


at every coaxial cable.




Now, explanation of a preferred embodiment of this invention will be made with reference to drawings, applying this invention to a multi-coaxial connector.




Referring to

FIGS. 4 and 5

, a multi-coaxial connector


3


is mounted on a circuit board


4


, and is coupled, at its front side, with a mating connector


100


shown in

FIG. 6

, which accommodates six coaxial cables


120


in this embodiment. Such multi-coaxial connector


3


comprises an insulator housing


5


with an open rear end


53


, a metallic block


6


with a front end surface fitted into the housing


5


through the open rear end


53


, as shown in FIG.


5


. For example, the insulator housing


5


is made of plastic material.




The metallic block


6


further has a rear end surface and six through-holes


61


which are formed in the metallic block


6


to extend in parallel with each other between the front and rear ends of the metallic block


6


. In this embodiment, the through-holes


61


are arranged two rows and three columns of a matrix as viewed from the rear end of the metallic block


6


, as shown in FIG.


5


.




The illustrated multi-coaxial connector


3


further has contact elements


71


,


72


and insulator sleeves


8


, both six in number.




Each of the contact elements


71


,


72


has a support portion, a contact portion


75


, and a terminal portion


77


. The support portion has opposite front and rear ends. Especially, in order for the connector


3


to be mounted on the circuit board


4


perpendicular to the connection face of the connector


3


and the mating connector, the support portion is bent at an intermediate portion thereof. Therefore, each of the contact elements


71


,


72


forms an L-shape having a foot portion


73


(


74


) and a leg portion, that will be referred to as an L-shaped contact element


71


(


72


). The contact portion


75


extends from the front end of the support portion, to form a tip of the foot portion


73


(


74


). The terminal portion


77


extends from the rear end of the support portion, to form a tip of the leg portion.




Each of the insulator sleeves


8


is fitted on the foot portion


73


(


74


) of each of the L-shaped contact elements


71


(


72


) and is fitted in each of the through-holes


61


. Thus, the L-shaped contact elements


71


,


72


are stationarily supported in the through-holes


61


, in a state that the L-shaped contact elements


71


,


72


are electrically insulated from the metallic block


6


. Herein, the L-shaped contact elements


71


,


72


function as coaxial inner conductors, while the metallic block


6


functions as a coaxial common outer conductor.




Now, further explanation, more in detail, will be made about the connector of this embodiment, together with

FIGS. 7 through 11

, too.




Referring to

FIGS. 5

,


7


and


10


, the insulator housing


5


is in a box-shaped form further having a front end wall opposite to the open rear end, and an upper wall. The front end wall is formed with six through-holes


57


which extend in a front-to-rear direction and correspond to the through-holes


61


of the metallic block


6


, as shown in

FIGS. 5 and 7

through


10


. The upper wall is formed with an elastic finger


51


having stoppers


54


projecting downwards, as shown in

FIGS. 5 and 10

, while depressed portions


62


are formed on an upper outer surface of the metallic block


6


, as shown in FIG.


5


. The depressed portions


62


receive the stoppers


54


, respectively, when the insulator housing


5


is mounted on the metallic block


6


with the front end wall being disposed adjacent the front end surface of the metallic block


6


. Thus, the stoppers


54


and the depressed portions


62


are fixedly engage the insulator housing


5


to the metallic block


6


.




The illustrated insulator housing


5


further has two guide rims


52


, two hook-type projections


55


, and a connector positioning projection


56


. On the other hand, the mating connector


100


has two guide grooves


112


and two slots


111


both shown in

FIG. 6

, and the circuit board


4


has a connector positioning hole


41


shown in FIG.


9


. The guide rims


52


are formed on the upper wall of the insulator housing


5


to guide the mating connector


100


, by interacting with the guide grooves


112


. The hook-type projections


55


are formed at bottom of the insulator housing


5


to lock the connecting condition between the multi-coaxial connector


3


and the mating connector


100


, by being engaged with the slots


111


. The connector positioning projection


56


is engaged with the connector positioning hole


41


and, thereby, positions the multi-coaxial connector


3


on the circuit board


4


.




In this embodiment, the metallic block


6


is a die-cast metallic block and is in a rectangular form having a bottom surface perpendicular to the rear end surface. Such metallic block


6


is provided with three grooves


66


formed in the rear end surface thereof. Each of the grooves


66


corresponds to each of the columns of the through-holes


61


and is connected to the through-holes


61


and, extends to the bottom surface of the metallic block


6


. The leg portions of the respective contact


71


,


72


are received in the groove


66


, while the terminal portion


77


projects outward from the bottom surface of the metallic block


6


.




The illustrated L-shaped contact elements


71


,


72


are grouped into two types: large type and small type, that will be also referred to as large and small type contact elements, respectively. Specifically, the large type contact elements


71


are three and are disposed in through-holes


61


of upper row, while the small type contact elements


72


are three, too, and are disposed in through-holes


61


of lower row. To accommodate pairs of the large and the small type contact elements


71


and


72


, the grooves


66


comprise three stairlike grooves, each of which varies in a groove depth and extends in and along the three column of the through-holes


61


. In

FIG. 5

, a direction of the groove depth is shown as Y direction, while another direction of the column is shown as Z direction. Furthermore, the each stairlike groove


66


has a stairlike bottom of two steps corresponding to two rows of the through-holes


61


, to be more in the groove depth at a position corresponding to a lower one of the two rows.




The leg portions of the pair of L-shaped contact elements


71


and


72


are received, in common, in the corresponding one of the stairlike grooves


66


but are separated from each other to leave a space therebetween in a direction of the groove depth, namely Y direction in FIG.


5


.




The number of the stairlike grooves


66


may increase in accordance with the increasing of the number of columns, while the number of the steps of each stairlike groove


66


may increase in accordance with the increasing of the number of rows. Both of the increased stairlike grooves


66


and their steps can be formed in the same manner mentioned above. Furthermore, such variation of the stairlike grooves


66


allows the number of the L-shaped contact elements


71


,


72


to increase.




The illustrated multi-coaxial connector


3


further comprises six insulator pieces


82


,


84


which are classified into small and large types, that will be also called small and large insulator pieces hereinafter. The small insulator pieces


82


are mounted on the leg portions of the small contact elements


72


, while the large insulator pieces


84


are mounted on the leg portions of the large contact elements


71


. All of the insulator pieces


82


,


84


are fitted in the stairlike grooves


66


at the steps thereof, respectively, so as to electrically insulate the leg portions of the contact elements


71


,


72


from the metallic block


6


. In detail, the small insulator pieces


82


are located in deep portion of the stairlike grooves


66


, depending on the deep insertion of the small contact elements


72


into the metallic block


6


.




Also, the illustrated multi-coaxial connector


3


further comprises a partitioning plate


91


disposed in the space between the leg portions of the pair of L-shaped contact elements


71


,


72


. In this embodiment, the partitioning plate


91


is sandwiched by the pairs of the small and large insulator pieces


82


,


84


, as shown in

FIGS. 8 and 9

. The partitioning plate


91


is made of, for example, metal material and has three protruding portions


92


protruding upwards, six pins


93


projecting downwards and two lateral projections


94


projecting to opposite side. The number of the partitioning plate


91


may increase, corresponding to the number of rows.




Each of the grooves


66


has opposite side walls


67


and opposite slits


68


in the side walls


67


to extend in a direction of the groove


66


extending, respectively. And also, the metallic block


6


further has bottom slits


63


in the bottom surface thereof to extend in a direction of the rows and to cross the grooves


66


. The protruding portions


92


of the partitioning plate


91


are fitted into the opposite slits


68


and the lateral projections


94


are fitted into the bottom slits


63


. Thus, the partitioning plate


91


is fixedly accommodated in the metallic block


6


with the pins


93


projecting from the bottom surface of the metallic block


6


.




Moreover, the illustrated multi-coaxial connector


3


comprises a rear end plate


95


mounted on the rear end of the metallic block


6


. The rear end plate


95


is made of, for example, metal material and has an engaging projection


96


, four positioning holes


97


and six projecting pins


98


. Herein, the metallic block


6


further has a cut-away portion


65


which is formed on an edge of the rear end surface.




The rear end plate


95


covers an entire rear end surface of the metallic block


6


with the engaging projection


96


engaged with the cut-away portion


65


. Furthermore, the metallic block


6


has four positioning projections


64


which are formed on the rear end surface of the metallic block


6


and are fitted into the positioning holes


97


of the rear end plate


95


, respectively. When the rear end plate


95


covers the rear end surface of the metallic block


6


, such positioning projections


64


are deformed to thereby fix the rear end plate


95


to the metallic block


6


.




With this structure, the number of parts comprising the multi-coaxial connector decreases, because the metallic block


6


is common to all of the contact elements


71


,


72


and functions as a coaxial common outer conductor.




Beside that, such structure of the connector


3


is easy to manufacture. In detail, manufacturing process of the embodiment comprises the following six steps:




1) fitting the insulator sleeve


8


on the support portion of the respective contact element


71


,


72


,




2) capping the front end surface of the metallic block


6


with the insulator housing


5


,




3) inserting the small contact elements


72


together with the insulator sleeves


8


into the lower through holes


61


of the metallic block


6


, respectively,




4) partitioning the stairlike grooves


66


with the partitioning plate


91


,




5) inserting the large contact elements


71


together with the insulator sleeves


8


into the upper through-holes


61


of the metallic block


6


, respectively, and




6) covering the rear end surface of the metallic block


6


, by engaging the positioning projections


64


with the positioning holes


97


, and then, by deforming the positioning projections


64


, as shown in FIG.


11


. That is, manufacturing process becomes easy, in accordance with the one aspect of the present invention.



Claims
  • 1. A multi-coaxial connector comprising:a metallic block having a front end surface and a rear end surface and being formed with a plurality of first through-holes therein extending in parallel with each other between said front end and said rear end of the metallic block; a plurality of contact elements disposed in said plurality of first through-holes, respectively, each of said plurality of contact elements comprising a support portion having opposite front and rear ends, a contact portion extending from said front end of said support portion, and a terminal portion extending from said rear end of said support portion; a plurality of insulator sleeves, each being fitted on said support portion of each of said contact elements, said insulator sleeves being fitted in said plurality of first through holes so that said contact elements are stationarily supported in said plurality of first through-holes, respectively in a state that said contact elements are electrically insulated from the metallic block, said contact elements and said metallic block functioning as coaxial inner conductors and a coaxial common outer conductor, respectively; and an insulator housing having an open rear end and a front end wall, said insulator housing being mounted on said metallic block with said front end wall being disposed adjacent said front end surface of said metallic block, said front end wall being formed with a plurality of second through-holes extending in a front-to-rear direction and corresponding to said first through-holes of the metallic block; wherein said metallic block is in a rectangular form having a bottom surface perpendicular to said rear end surface; said metallic block is provided with a plurality of grooves formed in said rear end surface so that said grooves are connected to said first through-holes and extend to said bottom surface; and each of said contact elements is bent at an intermediate portion of said support portion to form an L-shape comprising a foot portion including said contact portion and a leg portion including said terminal portion, said leg portion begin received in a corresponding one of said grooves together with a corresponding one of said insulator sleeves, while said terminal portion projects outward from said bottom surface of said metallic block.
  • 2. A multi-coaxial connector claimed in claim 1, wherein the metallic block is a die-cast metallic block.
  • 3. A multi-coaxial connector claimed in claim 1, wherein:said insulator housing is in a box-shaped form having an upper wall, said upper wall being formed with an elastic finger having stoppers projecting downwards; and said metallic block has an upper outer surface corresponding to said upper wall of said insulator housing, said upper outer surface being formed with depressed portions which receives said stoppers, respectively, so as to fixedly engage said insulator housing to said metallic block.
  • 4. A multi-coaxial connector claimed in claim 1, wherein:said first through-holes are arranged in m rows and n columns, m and n being integers, of a matrix as viewed from the rear end of said metallic block, said first through-holes being classified into m row through-hole groups each comprising n first through-holes arranged in each of said m rows and also classified into n column through-hole groups each comprising m first through-holes arranged in each of said n columns; said contact elements are classified into m row contact groups each comprising n contact elements disposed in said n first through-holes in each of said m row through-hole groups and also classified into n column contact groups each comprising m contact elements disposed in said m first through-holes in each of said n row through-hole groups; said plurality of grooves comprises n stairlike grooves varying in a groove depth and extending in and along said n columns, each of said n stairlike grooves having a stairlike bottom of m steps corresponding to said m rows to be more in the groove depth at a position corresponding to a lower one of said m rows; said leg portions of said m contact elements in each of said n column contact groups are received, in common, in a corresponding one of said stairlike grooves but are separated from each other to leave spaces therebetween in a direction of the groove depth.
  • 5. A multi-coaxial connector claimed in claim 4, further comprising:a plurality of insulator pieces mounted on said leg portions of said contact elements and fitted in said n stairlike grooves at said steps thereof, respectively, so as to electrically insulate said leg portions of said contact elements from said metallic block.
  • 6. A multi-coaxial connector as claimed in claim 5, which further comprises a plurality of partitioning plates disposed in said spaces.
  • 7. A multi-coaxial connector claimed in claim 6, wherein:each of said grooves has opposite side walls and opposite slits in said side walls to extend in a direction of said groove extending, respectively, each of said partitioning plates being fitted into said opposite slits.
  • 8. A multi-coaxial connector claimed in claim 7, wherein:said metallic block further has bottom slits in said bottom surface thereof to extend in a direction of said rows and to cross said grooves, and said partitioning plates have lateral projections fitted in said bottom slits.
  • 9. A multi-coaxial connector claimed in claim 5, wherein said partitioning plates are all made of metal material and have a plurality of pins projecting downwards.
  • 10. A multi-coaxial connector claimed in claim 5, further comprising a rear end plate mounted on the rear end of the metallic block.
  • 11. A multi-coaxial connector claimed in claim 10, wherein:said metallic block further has a cut-away portion formed on an edge of the rear end surface; and said rear end plate covers an entire rear end surface of said metallic block and has an engaging projection engaged with said cut-away portion.
  • 12. A multi-coaxial connector claimed in claim 11, wherein:said rear end plate has a plurality of positioning holes; and said metallic block has a plurality of positioning projections formed on the rear end surface of the metallic block and fitted into said positioning holes, respectively, and deformed to thereby fix said rear end plate to said metallic block.
  • 13. A multi-coaxial connector claimed in claim 8, wherein said rear end plate is made of metal material and has a plurality of pins projecting downwards.
  • 14. A multi-coaxial connector claimed in claim 1, wherein the insulator housing is made of plastic material.
  • 15. A multi-coaxial connector claimed in claim 1, adapted to be connected with a mating connector of the multi-coaxial connector having guide grooves, wherein the insulator housing further has guide rims on upper surface thereof, to guide the mating connector.
  • 16. A multi-coaxial connector claimed in claim 15, adapted to be installed on a circuit board having a connector positioning hole, wherein the insulator housing further has a connector positioning projections projecting downwards to position the multi-coaxial connector on the circuit board, by being engaged with the connector positioning hole.
  • 17. A multi-coaxial connector claimed in claim 14, the mating connector further having a plurality of slots, wherein the insulator housing has a plurality of hook-type projections at bottom thereof, to lock the connecting condition between the multi-coaxial connector and the mating connector, by being engaged with the slots, respectively.
Priority Claims (1)
Number Date Country Kind
10-313313 Nov 1998 JP
US Referenced Citations (4)
Number Name Date Kind
RE. 36065 Andrews et al. Jan 1999
5108300 Weber Apr 1992
5842872 Hosler et al. Dec 1998
6071127 Acke et al. Jun 2000
Non-Patent Literature Citations (1)
Entry
European Search Report (The Hague) completed Feb. 22, 2000 for Application No. EP 99 12 1862 and the following patents: (1) EP 0 862 243 A(Siemens AG); (2) WO 97 02629 A (Whitaker Corp); (3) U.S. Patent 4,659,156 dated Apr. 21, 1987 (Johnescu et al); (4) EP 0 582 960 A (Siemens AG); and (5) EP 0 488 482 A (DuPont Nederland; DuPont US).