Patent Publication Number: US-2009221189-A1

Title: Press-contacting conductive terminal device

Description:
FIELD OF THE INVENTION 
     The present invention relates to a press-contacting conductive terminal device and particularly to a device which can be used as a test probe or used for electrically connecting two devices together. To save material and to reduce its weight and cost, a metal shell completely enclosing the contact member moving chamber is eliminated. 
     BACKGROUND OF THE INVENTION 
     Referring to  FIG. 1 , a known press-contacting conductive terminal can be used as a test probe or used for electrically connecting two devices together. The press-contacting conductive terminal comprises a shell  10   a , a contact member  20   a  and a resilient member  30   a.  The shell  10   a  is integrally molded with metal material into a hollow cylinder. The front end of the shell  10   a  is open and the rear end of the shell  10   a  is closed. The contact member  20   a  is also made of a conductive material. The resilient member  30   a  and the contact member  20   a  are inserted into the shell  10   a  from the front end of the shell  10   a.  Thereafter, the front end of the shell  10   a  is riveted to form a rather small opening  11   a . The contact member  20   a  and the resilient member  30   a  are thereby held in the shell  10   a  because of the rather small opening  11   a . The front end of the contact member  20   a  extends through the opening  11   a  and beyond the front end of the shell  10   a  due to the force of the resilient member  30   a.    
     The above-mentioned press-contacting conductive terminal may be inserted a through hole  41   a  (see  FIG. 2 ) of a non-conductive enclosure  40   a.  Additionally, a pair of press-contacting conductive terminals are generally inserted into two corresponding through holes  41   a  (see  FIG. 3 ) of the non-conductive enclosure  40   a  side by side so as to transmit both negative and positive power. 
     In a practical use, the rear end of the shell  10   a  may be fixed to and electrically connected directly to a surface of a circuit board or by a through hole. Both the front end of the contact member  20   a  and the rear end of shell  10   a  may be contacted to transmit a signal between the two points. However, for the known press-contacting conductive terminal, a large amount of metal material is needed to provide the cylindrical metal shell  10   a.  Also, the metal shell  10   a  is rather heavy. Furthermore, the front end of the shell  10   a  needs to be riveted, which takes much time and energy, and must be performed carefully to ensure that the diameter of opening  11   a  is within tolerances after riveting. If the diameter of the opening  11   a  is too large, the contact member  20   a  is easily swayed. If the diameter is too small, the movement of contact member  20   a  may be blocked. 
     Accordingly, as shown above, the known press-contacting conductive terminal devices are in need of improvement to reduce cost. The inventors believe that the invention presented below will provide this improvement. 
     SUMMARY OF THE INVENTION 
     A main object of the present invention is to provide a press-contacting conductive terminal device, which can omit a cylindrical metal shell of the known technology, and uses an inner wall of a through hole of a non-conductive enclosure to partially replace the metal shell. By omitting the metal shell, there will be a saving of material, a reduction of weight, and a reduction in cost. Also additional electrical contact is made between the movable contact member and the two side wings extending within the contact chamber. Another object of the present invention is to provide a press-contacting conductive terminal device, wherein an opening may be formed in the non-conductive enclosure where the aperture diameter of the opening is easily controlled. 
     To fulfill the above-mentioned objects, the present invention provides a press-contacting conductive terminal device including a non-conductive enclosure defining a cylindrically shaped through hole where the front end and a rear end of the through holes have a first opening and a second opening, respectively. At least one contact member is received in the cylindrically shaped through hole. The contact member has a front end portion and a rear end portion. The outside diameter of the rear end portion is slightly larger than the outside diameter of the front end portion which keeps the contact member from passing out of the front end of the through hole. At least one resilient member is received in the through hole with one end abutting and placing a force against the rear end portion of the contact member. This force will cause the contact member to moveably extend though the first opening beyond the front end of the non-conductive enclosure. At least one base includes two side wings and a contact portion. The side wings extend together from the contact portion. The contact portion covers the second opening on the rear end of the through hole. The two side wings of the base partially form the inner walls of the cylindrical though hole. 
    
    
     
       DESCRIPTION OF THE DRAWING 
       The technical means and effects used in this invention to realize the objects of the invention will be further described combining with the detailed descriptions and the accompanying drawings. But it is to be understood that the invention is not limited to the accompanying drawings. 
         FIG. 1  is a cross-sectional view of a known press-contacting conductive terminal (no non-conductive enclosure); 
         FIG. 2  is a whole cross-sectional view of a known press-contacting conductive terminal; 
         FIG. 3  is a whole cross-sectional view of a pair of known press-contacting conductive terminals; 
         FIG. 4  is an exploded perspective view of a press-contacting conductive terminal device of the present invention; 
         FIG. 5  is an assembled perspective view of a press-contacting conductive terminal device of the present invention; 
         FIG. 6  is an assembled perspective view of a press-contacting conductive terminal device of the present invention with another viewpoint; 
         FIG. 7  is a front view of a press-contacting conductive terminal device of the present invention; 
         FIG. 8  is a cross-sectional view along  8 - 8  of  FIG. 7 ; 
         FIG. 9  is an exploded perspective view of a part of a press-contacting conductive terminal device of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIGS. 4 to 9 , the present invention relates to a press-contacting conductive terminal device. The conductive terminal device comprises a non-conductive enclosure  10 , at least one base  20 , at least one contact member  30 , and at least one resilient member  30 . The non-conductive enclosure  10  defines at least one cylindrically shaped through hole  11 . The through hole  11  extends from a front end through a rear end of the non-conductive enclosure  10 . The through hole  11  has a first opening  111  at the front end of the non-conductive enclosure  10  and a second opening  112  at the rear end of the non-conductive enclosure  10 . An inner diameter of the first opening  111  is less than that of the through hole  11 . A stop portion  113  is thereby defined by the first opening  111  shrinking abruptly to prevent the rear end  32  of the contact member  30  from moving out of the through hole  11 . The stop portion  113  is integrally formed with the non-conductive enclosure  10  at the front end of the non-conductive enclosure  10 , so as to easily control the size of the aperture diameter of the first opening  111 . 
     The contact member  30  is made of a metal material with good conductivity, and is received in the through hole  11 . The contact member  30  is configured to be hollow or solid. The contact member  30  consists of a front end portion  31  whose outside diameter is less than the inside diameter of the first opening  111  and a rear end portion  32  whose outside diameter is larger than the inside diameter of the first opening  111  while less than the inside diameter of the through hole  11 . This will allow the contact member  30  to freely move within the through hole  11  of the non-conductive enclosure  10 . The rear end portion  32  of the contact member  30  is disposed in the through hole  11 , and the front end portion  31  of the contact member  30  extends through the first opening  111  and beyond the front end of the non-conductive enclosure  10 . 
     The resilient member  40  is a compressive spring, made of a conductive material, and is disposed in the through hole  11 . One end of the resilient member  40  abuts against the inner portion of the contact member  30  and the other end of the resilient member  40  abuts against the contact portion  22  of the base  20 . An electrical connection is made by this resilient member  40  engaging both the contact member  30  and the base  20 . The resilient member pushes the front end portion  31  of the contact member  30  to resiliently extend beyond the front end of non-conductive enclosure  10 . 
     The base  20 , which is made of metal material with good conductivity, has two side wings  21  and a contact portion  22 . The side wings  21  both integrally extend upwardly from the contact portion  22 , and the side faces have a plurality of interfering portions  23 , such as protrusions or barbs. Two inner slots  114  which correspond to the side wings  21  of the base  20  are defined at the second opening  112  of the non-conductive enclosure  10  and extend along the axial direction of the though hole  11 . These inner slots  114  are located at two sides of the through hole  11 . The two side wings  21  of the base  20  are inserted into the two inner slots  114  respectively, and are held in place with the interfering portions  23  embedded within the inner slots  114 . The side wings  21  extend a suitable distance from the first opening  111  into the through hole to provide contact with the rear end  32  of the contact member  30  and the side wings  21  during the sliding movement of the contact member within the through hole. 
     During assembly, after the contact member  30  and the resilient member  40  are inserted into the through hole  11 , the side wings  21  of the base  20  are aligned with the inner slots  114  and inserted into the through hole  11 . Thereafter, the base  20  is assembled to the second opening  112  of the non-conductive enclosure  10  to close the second opening  112  of the rear end of the through hole  11 . Since the resilient member  40  is located between the base  20  and the contact member  30 , the front end portion  31  of the contact member  30  extends resiliently through the first opening  111  and beyond the front end of the non-conductive enclosure  10  due to the force of the resilient member  40 . The rear end  32  of the contact member  30  is set between the two side wings  21  of the base  20  where the outer wall of the rear end  32  slides in continuous electrical contact with the inner walls of the two side wings  21  of the base  20 . This makes the electric connection between the contact member  30  and the base  20 . An electrical connection is also made between the contact member  30  and the base  20  by way of the conductive resilient member  40 . 
     It will be understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.