Patent Publication Number: US-7717756-B1

Title: Probe connector

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a probe connector, and particularly to a probe connector having a structure capable of improving the connection stability between a barrel and a plunger thereof. 
     2. The Related Art 
     A probe connector mainly used in an electronic device generally includes a cylindraceous barrel, an elastic element assembled inside the barrel, and a plunger mounted to the barrel and partly projecting outside the barrel for contacting an outer electronic component. The plunger is pressed downwards by the electronic component to deflect to contact the barrel for achieving electrical connection. In order to improve the connection stability of the barrel and the plunger, conventionally, the plunger is formed with a ramped bottom surface which rests against an end of the elastic element. The ramped bottom surface of the plunger makes the elastic element compress and distort, in turn, the elastic element is provided with an opposite force which acts on the ramped bottom surface and slants the plunger to touch the barrel. However, such electrical connection between the barrel and the plunger is unstable and apt to break off instantly and discontinuously when the probe connector suffers from an unexpected force. 
     SUMMARY OF THE INVENTION 
     Accordingly, an object of the present invention is to provide a probe connector having a structure capable of improving connection stability between a barrel and a plunger thereof. The barrel includes a cylindraceous main body which defines a chamber therein, and a base connected with one end of the main body. The main body has an opening at a substantially middle portion thereof. The plunger includes a basic portion restricted in the barrel, and a contact portion extended from one end of the basic portion and exposed from the other end of the main body. A wrapping element surrounds an outer periphery of the main body. A resting element has a resting portion of arc shape, and two fixing slices extended opposite to each other from two ends of the resting portion. The resting portion projects into the chamber of the barrel through the opening. The fixing slices are sandwiched between the barrel and the wrapping element. The resting portion rests against a side of the basic portion when the contact portion is pressed downwards to deflect to contact an inner surface of the main body by an opposite side thereof. 
     As described above, the fixing slices of the resting element are sandwiched between the barrel and the wrapping element for fixing the resting element. The resting portion projects into the chamber through the opening. When the plunger is pressed downwards to make the basic portion extrude the resting portion outwards, in turn, the resting portion provides the opposite force pushing the basic portion to contact the inner surface of the main body securely, preventing the basic portion from breaking off the main body instantly and discontinuously when the probe connector suffers from the unexpected force. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be apparent to those skilled in the art by reading the following description, with reference to the attached drawings, in which: 
         FIG. 1  is an assembled, perspective view of a probe connector of a first embodiment in accordance with the present invention; 
         FIG. 2  is an exploded, perspective view of the probe connector shown in  FIG. 1 ; 
         FIG. 3  is a cross-sectional view of the probe connector shown in  FIG. 1 ; 
         FIG. 4  is a cross-sectional view of the probe connector shown in  FIG. 1 , wherein a plunger is pressed inside a barrel; 
         FIG. 5  is a cross-sectional view of a probe connector of a second embodiment in accordance with the present invention; 
         FIG. 6  is a cross-sectional view of a probe connector of a third embodiment in accordance with the present invention; and 
         FIG. 7  is a cross-sectional view of a probe connector of a fourth embodiment in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     With reference to  FIGS. 1-3 , the first embodiment in accordance with the present invention is embodied in a probe connector  1 . The probe connector  1  includes a hollow barrel  11 , a plunger  12 , and an elastic element  13  received in the barrel  11 . The barrel  11  and the plunger  12  are made of metallic material. The elastic element  13  defines a first end  13   a  and a second end  13   b  opposite to the first end  13   a.    
     The barrel  11  has a cylindraceous main body  11   a  which defines a chamber  11   d  therein, and a base  11   b  integrally sealed one end of the main body  11   a  for being against the first end  13   a  of the elastic element  13 . The main body  11   a  has an opening or a slot  11   c  at a substantial middle portion thereof and communicating with the chamber  11   d . In this embodiment, the slot  11   c  extends along a longitudinal direction of the main body  11   a . The other end of the main body  11   a  is bent inwards to form an opening  11   e  when the plunger  12  is mounted to the barrel  11 , for fixing the plunger  12  and the barrel  11  together. The base  11   b  is a short-pillar shape and has an outer diameter larger than that of the main body  11   a.    
     The plunger  12  of cylindrical shape includes a basic portion  12   a , and a contact portion  12   b  extending outwards from one end of the basic portion  12   a . The basic portion  12   a  defines a ramped bottom surface  12   c  opposite to the contact portion  12   b  and against the second end  13   b  of the elastic element  13 . The diameter of the contact portion  12   b  is less than that of the basic portion  12   a , with a free end shaped as a dome. The basic portion  12   a  is received in the chamber  11   d  of the barrel  11  and the contact portion  12   b  extends out of the barrel  11  through the opening  11   e . The outer dimension of the basic portion  12   a  is less than the inner dimension of the main body  11   a  for allowing the basic portion  12   a  to be inclinably received in the chamber  11   d . The dimension of the opening  11   e  is less than the outer dimension of the basic portion  12   a  for preventing the basic portion  12   a  from removing out of the chamber  11   d.    
     The probe connector  1  further has a resting element  14  mounted to the main body  11   a , and a wrapping element  15  surrounding the main body  11   a . The resting element  14 , which may be bent with a metal strip, has an arc-shaped resting portion  14   b  and two fixing slices  14   a  extended opposite to each other from two free ends of the resting portion  14   b . The wrapping element  15  is a cylinder, with an inner diameter thereof substantially the same as an outer diameter of the main body  11   a . An inner surface of the wrapping element  15  is formed with a receiving groove  15   a  extending longitudinally and reaching two opposite edges thereof. In this embodiment, the receiving groove  15   a  has a depth substantially the same as a thickness of the fixing slices  14   a . In assembly, the resting portion  14   b  is inserted into the chamber  11   d  of the barrel  11  through the slot  11   c . The fixing slices  14   a  are disposed to lean against an outer surface of the main body  11   a . The wrapping element  15  slidably fits around the main body  11   a  and is supported by the base  11   b , with the fixing slices  14   a  received in the receiving groove  15   a . A circumferential outer surface of the wrapping element  15  is substantially the same as a circumferential outer surface of the base  11   b . The fixing slices  14   a  are sandwiched between the main body  11   a  and the wrapping element  15  for fixing the resting element  14 . 
       FIG. 5  is a cross-sectional view showing a probe connector  2  of the second embodiment. The probe connector  2  is analogue to the probe connector  1  in the first embodiment except for the receiving groove. In the second embodiment, there are two receiving grooves  21   f  which are formed at an outer periphery of the main body  21  and symmetrical about the slot  21   c . The receiving grooves  21   f  communicate with the slot  21   c  for receiving the fixing slices  24   a  of the resting element  24  when the resting portion  24   b  is inserted into the slot  21   c . In this embodiment, the depth of the receiving groove  21   f  is substantially the same as the thickness of the fixing slice  24   a.    
       FIGS. 6-7  illustrate probe connectors  3  and  4  in the third and fourth embodiments, which are both substantially the same as the probe connector  1  in the first embedment except for the plungers. In the third embodiment, the basic portion  32   a  of the plunger  32  has a columned restraining hole  32   c  at a bottom thereof, for receiving the second end  33   b  of the elastic element  33 . In the fourth embodiment, the plunger  42  is shaped with a level bottom surface against the elastic element  43 . It should be noted that the construction of the probe connector can be modified for meeting the different demands and should not be limited. 
     Please refer to the  FIG. 4 , when the contact portion  12   b  of the plunger  12  is pressed downwards, the elastic element  13  is compressed downwards and distorted by the ramped bottom surface  12   c  of the basic portion  12   a  and generates an opposite force which acts on the ramped bottom surface  12   c  so that the basic portion  12   a  is deflected to contact an inner surface of the main body  11   a . The resting portion  14   b  is extruded outwards by the basic portion  12   a  and generates an opposite force which acts on a side of the basic portion  12   a  opposite to a contact side of the basic portion  12   a  which contacts with the main body  11   a  by means of deflection of the basic portion  12   a , reinforcing the contacting stability between the basic portion  12   a  and the main body  11   a , without affecting by an unexpected shock or the like. 
     As described above, the fixing slices are sandwiched between the barrel and the wrapping element. The resting portion projects into the chamber through the slot. When the plunger is pressed downwards to make the basic portion extrude the resting portion outwards, in turn, the resting portion provides the opposite force pushing the basic portion to contact the inner surface of the main body steadily. It prevents the basic portion from breaking off the main body instantly when the probe connector suffers from the unexpected force. 
     The foregoing description of the present invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. Such modifications and variations that may be apparent to those skilled in the art are intended to be included within the scope of this invention as defined by the accompanying claims.