Abstract:
A connecting structure for interengaging metallic shielding members is provided, which includes: a contacting elongation ( 2 ) at a leading edge of a cylindrical male metallic shielding member ( 1 ); a mating contacting elongation ( 4 ) at a leading edge of a cylindrical female metallic shielding member ( 3 ) which is brought into contact with the male member contacting elongation at the leading edge of the cylindrical male metallic shielding member; and a pair of engaging hook pieces ( 5 ) formed to extend circumferentially on the contacting elongation of one of the metallic shielding members to engage with the contacting elongation of the other metallic shielding member, wherein the pair of engaging hook pieces are formed at both sides of a slit ( 6 ) provided between the adjacent contacting elongations. The contacting elongation of either of the metallic shielding members is urged toward and into tighter contact with the contacting elongation of the other metallic shielding member by a pressing spring portion ( 23 ) provided on a housing ( 17 ′) of a connector ( 19 ).

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional application of U.S. patent application Ser. No. 08/609,749, filed Mar. 1, 1996, now U.S. Pat. No. 5,932,841. The subject matter of application Ser. No. 08/609,749 is hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a connecting structure for a metallic shielding member which shields electric noises is and ensures good contact between a male metallic shielding member and a female metallic shielding member. 
     2. Description of the Prior Art 
     FIGS. 9 to  11  show a conventional shielded connector as proposed in the Japanese Patent Application Laid-Open No. Hei 7-245153. 
     A female side connector  19  shown in FIG. 9 comprises a female connector housing  17  made of synthetic resin, a female side metallic shielding member  3  and a male terminal  25 . The female connector housing  17  has a cylindrical inner housing  27  at an inside of an outer housing  26  through a coupling portion  28 . An annular shield inserting gap  29  is formed between the outer housing  26  and the inner housing  27 , an inserting hole  30  toward a contacting elongation  4  in the leading edge direction of the metallic shielding member  3  is formed at the coupling portion  28 . 
     The metallic shielding member  3  is a cylindrical form, and the contacting elongation  4  divided four-part is provided at the leading edge of the cylindrical portion  31 . Each of the contacting elongations  4  is adjacent to each other through a wide slit  15 . An engaging piece  33  toward a connecting recess  32  of the inner housing  27  is formed at the inside of the contacting elongation  4 . A bottom end  15   a  of the slit  15  comes into contact with a rear end of the coupling portion  28 . 
     A male terminal  25  is arranged within the metallic shielding member  3 , and the male terminal  25  is connected to a shielded electric wire  34 . A base  35  of the metallic shielding member  3  is connected to a shield conductor  36  of the shielded electric wire  34 . 
     Moreover, a male side connector  37  shown in FIG. 10 is composed of a male connector housing  12 , male side metallic shielding member  38  and a female terminal  39 , according to an engagement between both connectors  19  and  37 , the male side metallic shielding member  38  is inserted into the female side metallic shielding member  31  at the same time that a male terminal  25  and a female terminal  39  are connected to each other. 
     The male connector housing  12  has an annular shield insertion gap  20  between an outer housing  13  and an inner housing  14  the same as above description. The male side metallic shielding member  38  has a contacting elongation for contacting  42  divided into four part by a slit  41  at the leading edge of a cylindrical part  40 . The contacting elongation  42  projects forward from the insertion hole  22  of the coupling portion  21  between the inner housing  14  and the outer housing  13  through the shield insertion gap  20 . An engaging piece  43  on the inside of the cylindrical portion  40  engages with a connecting groove  16  of the inner housing  14  at the same time of the above projection of the contacting elongation  42 . 
     FIG. 11 shows a connecting condition of both of metallic shielding members  3 ,  38 . Four pieces of the contacting elongations  4 ,  42  of each of metallic shielding members  3 ,  38  come into contact with each other with made overlapping alternately on the other side slits  41 ,  15 . 
     However, in the above conventional connecting structure of the metallic shielding member, at the beginning of connecting both of the contacting elongation  4 ,  42  are coming into closely contact with each other, there are some apprehensions that it becomes susceptible to be generated bad contact since a contacting pressure between both contacting elongations  4 ,  42  get weak with time in that the contacting elongations  4 ,  42  wear away according to vibration of the vehicle and so force or the male side contacting elongation  4  is forced to deform with opened outward. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing, it is an object of the present invention to provide a connecting structure for a metallic shielding member which can prevent an occurrence of bad contact thereof even if the vehicle vibrates. 
     According to the first aspect of the present invention, for achieving the above-mentioned object, there is provided a connecting structure for a metallic shielding member in which a contacting elongation in a leading edge direction of a cylindrical male metallic shielding member is forced to come into contact with a mating contacting elongation in a leading edge direction of a cylindrical female metallic shielding member wherein a pair of engaging hook pieces toward the contacting elongation of the metallic shielding member on one side are formed at the contacting elongation of the metallic shielding member on the other side. It is also possible in the above described structure wherein the pair of engaging hook pieces are formed at both sides of the slit provided between the adjacent contacting elongations with each other. 
     According to the second aspect of the present invention there is provided a connecting structure for a metallic shielding member in which it causes a connector equipped with the male side metallic shielding member and a mating connector equipped with the female side metallic shielding member to engage with each other, while coming into contact with the contacting elongations in the leading edge direction of both metallic shielding members mutually wherein a pressing spring portion which permits the contacting elongation either of the metallic shielding members to energize toward the mating contacting elongation of the other metallic shielding member is provided for at least a housing of the connector on one side. 
     According to the third aspect of the present invention there is provided a connecting structure for a metallic shielding member in which a contacting elongation in a leading edge direction of a cylindrical male metallic shielding member equipped with a male connector is forced to come into contact with a mating contacting elongation in a leading edge direction of a cylindrical female metallic shielding member equipped with a female connector wherein a contacting projection is formed at the contacting elongation of the metallic shielding member on one side, said contacting projection comes into contact with the mating contacting elongation of the metallic shielding member on the other side in case of engagement between the male connector and the female connector. It is also possible in the above described third aspect wherein an enlarged diameter portion is provided for the contacting elongation of the female side metallic shielding member whereby contacting projection is forced to come into contact with contacting elongation at the enlarged diameter portion. 
     As stated above, the contacting structure for the metallic shielding member according to the first aspect of the present invention is provided with the contacting elongation of the female side metallic shielding member joining and making overlapping to the mating contacting elongation of the male side metallic shielding member at the same time of engagement for both connectors. At this time, the contacting elongation (for example female side) on one side is inserted into the gap between a pair of engaging hook pieces, and is maintained with joined to the peripheral surface of the contacting elongation (for example male side) on the other side by means of the engaging hook piece. 
     Further, the contacting structure for the metallic shielding member according to the second aspect of the present invention there is provided the pressing spring portion which causes the contacting elongation of the metallic shielding member on one side to join with pressurized to the contacting elongation of the metallic shielding member on the other side at the same time of engagement for both connectors. 
     Furthermore, the contacting structure for the metallic shielding member according to the third aspect of the present invention there is provided the contacting projection in which each contacting elongation of both metallic shielding members is certainly connected by virtue of high contacting pressure of point contact of the contacting projection, since the contacting projections are positioned on the inside of the enlarged diameter portion, both of the contacting elongations are adjacent to each other. 
     The above and further objects and novel features of the invention will be more fully understood from the following detailed description when the same is read in connecting with the accompanying drawings. It should be expressly understood, however, that the drawings are for purpose of illustration only and are not intended as a definition of the limits of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view showing a connecting structure of a metallic shielding member according to the first embodiment of the present invention; 
     FIG. 2 is a longitudinal sectional view showing a connecting condition of the same as above FIG. 1; 
     FIG. 3 is a longitudinal sectional view showing a male connector and a female connector equipped with metallic shielding members; 
     FIG. 4 is a longitudinal sectional view showing a connecting condition of the female and male connectors of FIG. 1; 
     FIG. 5 is a perspective view showing a connecting structure of a metallic shielding member according to the second embodiment of the present invention; 
     FIG. 6 is an exploded perspective view showing a connecting structure of a metallic shielding member according to the third embodiment of the present invention; 
     FIG. 7A is a longitudinal sectional view showing a connecting condition of FIG. 6; 
     FIG. 7B is a longitudinal sectional view showing a transformational example of FIG. 6; 
     FIG. 8 is a longitudinal sectional view showing a connecting condition of the female and male connectors of FIG. 6; 
     FIG. 9 is a longitudinal sectional view showing a condition in which it causes the conventional female side metallic shielding member to mount on the housing; 
     FIG. 10 is a longitudinal sectional view showing a condition in which it causes the male side metallic shielding member to mount on the housing; and 
     FIG. 11 is a longitudinal sectional view showing a connecting condition of a conventional metallic shielding member. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Preferred embodiments of the invention will now be described in detail referring to the accompanying drawings. 
     FIGS. 1 and 2 show a connecting structure of a metallic shielding member according to the first embodiment of the present invention. 
     The connecting structure is characterized in a pair of engaging hook pieces  5  extend circumferentially on a contacting elongation  4  of one metallic shielding member  3  to engage a contacting elongation  2  of the other metallic shielding member  1 . 
     The pair of engaging hook pieces  5 ,  5  are formed at both sides of the wide slit  6  between the contacting elongations  2 ,  2  adjacent thereto, and are composed of a rising portion  8  which is protruded to a shield external diameter direction from slightly notched position, from the leading edge of the contacting elongation  2  to the width direction (circumferential direction) of the contacting elongation  2 , and a circular arc shaped supporting portion  9  protruded to slit width direction from the leading edge of the rising portion  8 . 
     A projection height H of the rising portion  8  is established the same numerical value as thickness of the wall of the contacting elongation  4  of the male side metallic shielding member  3  or only less than thereof. An index of curvature of the circular arc shaped supporting portion  9  is established so as to agree approximately with an index of curvature of the contacting elongation  4  of the female metallic shielding member  3 . A depth of the notching  7  is established so as to become in that an inner width S between the rising portions  8  of the pair of engaging hook piece  5 ,  5  are some larger than the width of the contacting elongation  4 . It should be added downward (direction for the center of metallic shielding member) energized force by means of the spring to the annular arc shaped supporting portion  9 . 
     The contacting elongation  4  of the female side metallic shielding member  3  is joined to the peripheral surface of a cylindrical portion  10  of the male side metallic shielding member  1  with inserted into the inside of the pair of engaging hook pieces  5 ,  5  faced each other with put the slit  6  therebetween. The annular arc shaped supporting portion  9  is joined to the outer surface of the contacting elongation  4  of the female side metallic shielding member  3  so that it causes the contacting elongation  4  to press always against the center of the metallic shielding member  1 . For this reason, even if both metallic shielding members  1 ,  3  are forced to vibrate with both metallic shielding members  1 ,  3  connected, contact pressure of both contacting elongations  2 ,  4  are not weakened. 
     In FIG. 1, a projection  11  which is formed protrusively at the outer side center of the contacting elongation  2  is a backlash preventing projection joined to an inner wall of the male connector housing  12  (outer housing  13 ) of FIG.  3 . The backlash preventing projection  11  is positioned within the slit  15  between the contacting elongations  4  of the other female side metallic shielding member  3 . Further an engaging piece  47  toward a connecting groove  16  of an inner housing  14  (referring to FIG. 3) is formed at the cylindrical portion  10  in the rear direction of the backlash preventing projection  11 . 
     FIG. 3 shows a condition that it causes the male and the female metallic shielding members  1 ,  3  to attach to the connector housings  12 ,  17  respectively. FIG. 4 shows a condition that it causes the male connector  18  to engage with the female connector  19 . The structure of each of connector housing  12 ,  17  and the female side metallic shielding member  3  are the same as the conventional one accordingly the descriptions of the common parts are omitted here to avoid unnecessary repetition. 
     In FIG. 3, the male side metallic shielding member  1  is inserted into the annular shield insertion gap  20  of the male side connector housing  12 . The contacting elongation  2  protrudes forward passing through the insertion hole  22  of the coupling portion  21  between the inner housing  14  and the outer housing  13 . The outer surface of the contacting elongation  2  is exposed to the outer side of the inner housing  14 . The engaging hook piece  5  is positioned protrusively at the leading edge of the contacting elongation  2 . 
     The contacting elongation  4  of the female side metallic shielding member  3  is inserted into the inside of the engaging hook piece  5  at the same time of the engagement for both connectors  18  and  19  as shown in FIG. 4, and is joined on the outer surface of the contacting elongation  2  of the male side metallic shielding member  1 . The condition of intimate contact between the contacting elongation  4  of the female side metallic shielding member  3  and the contacting elongation  2  of the male side is maintained by the engaging hook piece  5 , as a result thereof, the contacting elongation  4  is connected with the male side contacting elongation  2  with a stabilized contact pressure without looseness occurring with time. 
     In the above described embodiment, the engaging hook piece  5  are provided protrusively at the periphery side of the male side metallic shielding member  1 . However, there are possibilities for the engaging hook peace  5  to be provided protrusively at the inside of the female side metallic shielding member  3  in some shapes. In this manner, the contacting elongations of the male and the female metallic shielding members are overlapping with each other at the same position without the phase deviation thereof toward the circumferential direction. 
     FIG. 5 shows a connecting structure of a metallic shielding member according to the second embodiment of the present invention. This structure is characterized in that it causes a pressing spring piece  23  opposite to the other party contacting elongation  4 ′ of the female side metallic shielding member  3 ′ to form integrally at the male connector housing  17 ′ equipped with the female side metallic shielding member  3 ′. 
     The pressing spring piece  23  is formed protrusively toward diagonally forward from the inner wall  44  of the vacant room  24  in front of the coupling portion  28  between the inner housing  27  and the outer housing  26 . The pressing spring pieces  23  are positioned in front of the shield inserting hole  30  of the coupling portion  28  corresponding to the four pieces of contacting elongations  4 ′. 
     An annular projection  45  protruded toward outward is formed at the leading edge of the female side contacting elongation  4 ′. The leading edge portion of the pressing spring piece  23  comes into contact with the annular projection  45  with energized. The contacting elongation  42  of the male side metallic shielding member  38  is mounted on the inside of the male connector housing  12 , and the male side contacting elongation  42  is inserted into the inside of female side contacting elongation  4 ′. The female side contacting elongation  4 ′ is made overlapping with the contacting elongation  42  on the slit  41  of the male side metallic shielding member  38  same as above example. The male side contacting elongation  42  comes into contact with the upper part of the inner housing  14  which has a connecting groove  16  to the engaging piece  43 . 
     The female side contacting elongation  4 ′ is joined to the male side contacting elongation  42  by energizing force of the pressing spring piece  23  pressing toward the inside direction. Although the contacting elongation  4 ′ wears away by vibration of vehicle, the pressing spring piece  23  always permits the female side contacting elongation  4 ′ to press against the male side contacting elongation  42  accordingly certain contacting pressure is maintained. The pressing spring piece  23  prevents the deformation toward outwardly of the female side contacting elongation  4 ′. 
     In the above described second embodiment, it causes the pressing spring piece  23  to form integrally with the connector housing  17 ′ however, it is effective to provide a pressing spring piece made of metal (not shown) for the connector housing  17 ′ separately. Further it is possible to provide a pressing spring piece to the contacting elongation  4 ′ of the female side metallic shielding member  3 ′ for the outer housing  13  of the male connector housing  12  with the male side metallic shielding member  38  rather than the female connector housing  17 ′ with the female side metallic shielding member  3 ′. Furthermore, it is possible to provide a pressing spring piece which comes into contact with the inside surface of the male side contacting elongation  42  for the position of the connecting groove  16  of the inner housing  14  of the male connector housing  12  in FIG.  5 . 
     FIGS. 6 to  8  show a connecting structure for the metallic shielding member according to the third embodiment of the present invention. 
     This structure permits the contacting property between the metallic shielding member  48  and the metallic shielding member  49  to improve. It causes a plurality of hemispheric contacting projection  52  to form protrusively at the peripheral surface of the leading edge direction of the contacting elongation  50  of the male side metallic shielding member  48 , and it causes an annular enlarged diameter portion for contact  53  to the contacting projection  52  to form at the leading edge direction of the female side metallic shielding member  49 . 
     The metallic shielding member  48  has a pair of wide slits  54  opposite to each other along the length, and the metallic shielding member  49  has a pair of wide slits  55  opposite to each other along the length. It causes a pair of contacting elongations  50 ,  51  which have approximately half-round sectional form in the circumferential direction of 90° to the slits  54 ,  55  respectively. The contacting projections  52  are formed equally separated 90° in the leading edge direction of the contacting elongation  50 . The rigidity of the pair of contacting elongations  50 ,  51  is higher than that of the above described four pieces of the contacting elongations for example of  42  in FIG.  5 . The male side contacting elongations  50  which have strong outwardly elastic reaction force are virtually unbendable inward, and the female side contacting elongations  51  are virtually unbendable outward. Consequently, the male side and the female side contacting elongations have higher pressing pressure than the four pieces of the contacting elongations as described above. 
     The inner circumferential surface of the enlarged diameter portion for contact  53  extends in a straight line along the length from the leading edge of the contacting elongation  51 , a taper shaped portion  53   a  is formed at the base of the enlarged diameter portion  53 . An engaging piece  58  to the male connector housing  56  of FIG. 8 is notched outward at the base side of the contacting elongation of the male side metallic shielding member  48 , and an inward engaging piece  60  to the connecting step portion  59  of the female connector housing  57  is formed at the base side of the contacting elongation  51  of the female side metallic shielding member  49 . 
     As shown in FIG. 7A, the slit  54  of the metallic shielding member  48  is forced to deviate only 90° from the slit  55  of the metallic shielding member  49  in the circumferential direction so that the side portion of the contacting elongation  50  overlaps that of the contacting elongation  51 , as a result thereof, as shown in FIG. 8, the contacting projection  52  of the male side metallic shielding member  48  comes into pressurized contact with the inner circumferential surface of the enlarged diameter portion  53  of the female side metallic shielding member  49 . 
     As shown in FIG. 7B, it is possible to adopt the structure in which it causes a contacting projection  52 ′ to form protrusively at the inner side surface of the contacting elongation  51  of the female side metallic shielding member  49  rather than the male side metallic shielding member  48 , and to come into connectively contact with the contacting elongation  50  of the male side metallic shielding member  48 . In this case, it is desirable that the contacting projection  52 ′ is formed at the enlarged diameter portion  53  (referring to FIG. 6) of the female side metallic shielding member  49 . It is capable of maintaining the high shielded property in that the contacting projection  52  or  52 ′ which is positioned within the enlarged diameter portion  53  comes into contact with the contacting elongations  50 ,  51  of both of the metallic shielding members. 
     In FIG. 8, each of the pair of contacting elongations  50 ,  51  are protruded forward, with inserted into a shield insertion hole  62  positioned at a pair of coupling portion  61  connecting between the inner housing and the outer housing of the connector housings  56 ,  57 . The shield insertion hole of the female connector housing  57  is provided with respect to the shield insertion hole  62  of the connector housing  56 , at a position offset 90° in the circumferential direction. 
     As described above, according to the present invention, since the engaging hook piece or the pressing spring portion causes the contacting elongation of one side metallic shielding member to come into pressurized contact with the contacting elongation of the other side of the metallic shielding member, although the contacting elongation wear away by vibration of vehicle, the contacting elongations certainly come into contact with each other. The deformation toward the shield diameter direction of the contacting elongation by vibration is prevented, thereby a deterioration with time of contact pressure for the mutual contacting elongation is prevented. Bad contact between both metallic shielding members does not take place so that good shielded property is always exhibited. Further by forming the contacting projection at the contacting elongation, both metallic shielding members are capable of being connected certainly with strong contact pressure by the point contact of the contacting projection.