Patent Publication Number: US-11387587-B1

Title: Self-retained slider contact pin

Description:
TECHNICAL FIELD OF THE INVENTION 
     The present invention relates in general to a contact pin for electronic devices for providing a self-retained and compliant contact pin for connecting between electric circuits. 
     BACKGROUND OF THE INVENTION 
     Compliant contact pins and spring probes have long been provided for connecting between electric circuits in electronic devices such as those used in connectors, and in test and burn-in sockets. Spring contact pins have included those which are not self-retaining but are instead captured within apertures of a socket or a connector. Other spring biased contact pins have been self-retaining, that is, mating contacts of the contact pins are held together by interaction of the respective pins, such as pogo pins formed of extruded contacts which are held together by crimping and H-pins formed of stamped contacts which are held together by tabs from one set of contacts which extend within slots formed in mating contacts. When used with high frequency circuits it is important that the contact pins not introduce inductance, capacitance, and other unwanted impedance which may occur with compliant sliding point contacts under mechanical loads. 
     SUMMARY OF THE INVENTION 
     A self-retained slider contact pin is disclosed which has a first contact which is coined to form a first notch and a first finger, and a second notch and a second finger. The first finger and the second finger extend longitudinally relative to the first contact and generally parallel to the first notch and the second notch. A second contact is coined to form an opening and a first channel, and a second opening and a second channel. The first contact and the second contact inter-fit in alignment with the first finger extending through the opening and into the first channel and the second finger extending through the second opening and into the second channel, such that the first finger and the second finger retain together in sliding engagement the first contact and the second contact. A bias spring pushes apart the first contact and the second contact. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying Drawings in which  FIGS. 1 through 20  show various aspects for self-retained slider contact pins ade according to the present invention, as set forth below: 
         FIG. 1  is a perspective view of a self-retained slider contact pin; 
         FIG. 2  is a sectional view of the self-retained slider contact pin, taken along section line  2 - 2  of  FIG. 1 ; 
         FIG. 3  is a perspective view of part of the self-retained slider contact pin, showing a first contact engaged with a second contact; 
         FIG. 4  is an exploded view of the first contact separated from the second contact; 
         FIG. 5  is a perspective view of a second self-retained slider contact pin; 
         FIG. 6  is a sectional view of the second self-retained slider contact pin, taken along section line  6 - 6  of  FIG. 5 ; 
         FIG. 7  is a perspective view of part of the second self-retained slider contact pin, showing a first contact engaged with a second contact; 
         FIG. 8  is an exploded view of part of the second self-retained slider contact pin, showing first contact separated from the second contact; 
         FIG. 9  is a perspective view of a third self-retained slider contact pin; 
         FIG. 10  is a sectional view of part of the third self-retained slider contact pin, taken along section line  10 - 10  of  FIG. 9 ; 
         FIG. 11  is a perspective view of part of the third self-retained slider contact pin, showing a first contact engaged with a second contact; 
         FIG. 12  is an exploded view of part of the third self-retained slider contact pin, showing first contact separated from the second contact; 
         FIG. 13  is a perspective view of a fourth self-retained slider contact pin; 
         FIG. 14  is a sectional view of part of the fourth self-retained slider contact pin, taken along section line  14 - 14  of  FIG. 13 ; 
         FIG. 15  is a perspective view of part of the fourth self-retained slider contact pin, showing a first contact engaged with a second contact; 
         FIG. 16  is an exploded view of part of the fourth self-retained slider contact pin, showing first contact separated from the second contact; and 
         FIG. 17  is a perspective view of a fifth self-retained slider contact pin; 
         FIG. 18  is a sectional view of part of the fifth self-retained slider contact pin, taken along section line  18 - 18  of  FIG. 17 ; 
         FIG. 19  is a perspective view of part of the fifth self-retained slider contact pin, showing a first contact engaged with a second contact; and 
         FIG. 20  is an exploded view of part of the fifth self-retained slider contact pin, showing first contact separated from the second contact. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is a perspective view of a self-retained slider contact pin  12 . The contact pin  12  preferably has three separate components: a first contact  14 , a second contact  16 , and a bias spring  18 . The first contact  14  and the second contact  16  are configured to slidably fit together and interlock in a telescoping arrangement such that the overall combined length of the first contact  14  and the second contact  16  will expand and contract. The bias spring  18  is secured to engage between the first contact  14  and the second contact  16  to urge the first contact  14  and the second contact  16  to move apart, extending the overall combined length and providing compliance for electrically connecting between circuit conductors. Preferably the bias spring  18  is provided by a coil spring which is captured between tabs  28  and  30  of respective ones of the first contact  14  and the second contact  16 . The tab  28  has a shoulder  32  and the tab  30  has a shoulder  34  which engage against opposite terminal ends of the bias spring  18 . The respective end tips of the first contact pin  14  and the second contact pin  16  are provided by protuberances  20  and  22 . 
       FIGS. 2-4  are views of the self-retained slider contact pin  12 , in which  FIG. 2  is a sectional view taken along section line  2 - 2  of  FIG. 1 ,  FIG. 3  is a perspective view of the self-retained slider contact pin  12  with the bias spring  18  removed, and  FIG. 4  is an exploded view of the first contact  14  separated from the second contact  16 . The first contact  14  and the second contact  16  of the slider contact pin  12  are slidably interlocked in the telescoping arrangement by means of a finger  36  which extends from the first contact  12  through an opening  40  in the second contact  16 . The first contact  14  and the second contact  16  are each formed of respective strips of conductive material which preferably are formed by coining, or stamping, to have a length, a width and a thickness. Preferably the length is longer than the width is wide, and the thickness is nominal as compared to the width by an order of magnitude of at least four times the width. However, although length is generally thought of longer than width it may be determined in the opposite order in some circumstances contemplated by the present disclosure. The first contact  14  and the second contact  16  have widths defining flat surfaces  44  and  46 , respectively, which will slidably engage in electrical contact providing mating surface areas with electric continuity between the contacts  14  and  16 . 
     The first contact  14  is stamped from a strip of conductive material which preferably has an elongate body with a longitudinal axis  24 , forming a notch  38  where the finger  36  is pressed from the width of the strip of conductive material. The finger  36  is preferably an elongate section of conductive material having compliance which is stamped from the strip of material and extends with first a base  48 , then an intermediate section  49 , and then a terminal end tip  50 . The second contact  16  is coined from a second strip of conductive material preferably having an elongate body with a longitudinal axis  26 . An opening  40  is stamped into the second contact  16  and provides a window for passing the finger  36  through the second contact  16 . A channel  42  is also stamped into the second contact, preferably adjacent to the opening  40 . The channel  42  provides a guide for receiving a terminal end tip  50  of the finger  36  and guiding the terminal end tip  50  of the finger  36  as the first contact  14  and the second contact  16  slidably move relative to one another. The base  48  of the finger  36  will generally be disposed within and engage the edges of the opening  40  in the second contact  16 , which together with the compliance of the terminal end tip  50  engaging with the channel  42  provide that the first contact  14  and the second contact are self-retaining when assembled with the bias spring  18 . 
       FIG. 5  is a perspective view of a second self-retained slider contact pin  52 . The contact pin  54  preferably has three separate components: a first contact  54 , a second contact  56 , and a bias spring  58 . The first contact  54  and the second contact  56  are configured to slidably fit together and interlock in a telescoping arrangement such that the overall combined length of the first contact  54  and the second contact  56  will expand and contract. The bias spring  58  is secured to engage between the first contact  54  and the second contact  56  to urge the first contact  54  and the second contact  56  to move apart, extending the overall combined length and providing compliance for electrically connecting between circuit conductors. Preferably the bias spring  58  is provided by a coil spring which is captured between tabs  68  and  70  of respective ones of the first contact  54  and the second contact  56 . The tab  68  has a shoulder  72  and the tab  70  has a shoulder  74  which engage against opposite terminal ends of the bias spring  58 . The respective end tips of the first contact pin  54  and the second contact pin  56  are provided by protuberances  20  and  22 . 
       FIGS. 6-8  are views of the self-retained slider contact pin  52 , in which  FIG. 6  is a sectional view taken along section line  6 - 6  of  FIG. 5 ,  FIG. 7  is a perspective view of the self-retained slider contact pin  52  with the bias spring  58  removed, and  FIG. 8  is an exploded view of the first contact  54  separated from the second contact  56 . The first contact  54  and the second contact  56  of the slider contact pin  52  are slidably interlocked in the telescoping arrangement by means of a finger  76  which extends from the first contact  52  through an opening  80  in the second contact  56 . The first contact  54  and the second contact  56  are each formed of respective strips of conductive material which preferably are formed by coining, or stamping, to have a length, a width and a thickness. Preferably the length is longer than the width is wide, and the thickness is nominal as compared to the width by an order of magnitude of at least four times the width. However, although length is generally thought of longer than width it may be determined in the opposite order in some circumstances contemplated by the present disclosure. 
     The first contact  54  is stamped from a strip of conductive material which preferably has an elongate body with a longitudinal axis  64 , forming a notch  78  where the finger  76  is pressed from the width of the strip of conductive material. The finger  76  is preferably an elongate section of conductive material having compliance which is stamped from the strip of material and extends with first a base  88 , then an intermediate section  89 , and then a terminal end tip  90 . The second contact  56  is coined from a second strip of conductive material preferably having an elongate body with a longitudinal axis  66 . An opening  80  is stamped into the second contact  56  and provides a window for passing the finger  76  through the second contact  56 . A channel  82  is also stamped into the second contact, preferably adjacent to the opening  80 . The channel  82  provides a guide for receiving a terminal end tip  90  of the finger  76  and guiding the terminal end tip  90  of the finger  76  as the first contact  54  and the second contact  56  slidably move relative to one another. The base  88  of the finger  76  will generally be disposed within and engage the edges of the opening  80  in the second contact  56 , which together with the compliance of the terminal end tip  90  engaging with the channel  82  provide that the first contact  54  and the second contact are self-retaining when assembled with the bias spring  58 . The first contact  54  and the second contact  56  have widths defining flat surfaces  84  and  96 , respectively, which will slidably engage in electrical contact providing mating surface areas with electric continuity between the contacts  54  and  56 . 
       FIG. 9  is a perspective view of a third self-retained slider contact pin  92 . The third contact pin  92  preferably has three separate components: a first contact  94 , a second contact  96 , and a bias spring  98 . The first contact  94  and the second contact  96  are configured to slidably fit together and interlock in a telescoping arrangement such that the overall combined length of the first contact  94  and the second contact  96  will expand and contract. The bias spring  98  is secured to engage between the first contact  94  and the second contact  96  to urge the first contact  94  and the second contact  96  to move apart, extending the overall combined length and providing compliance for electrically connecting between circuit conductors. Preferably the bias spring  98  is provided by a coil spring which is captured between tabs  108  and  110  of respective ones of the first contact  94  and the second contact  96 . The tab  98  has a shoulder  112  and the tab  100  has a shoulder  114  which engage against opposite terminal ends of the bias spring  98 . The respective end tips of the first contact pin  94  and the second contact pin  96  are provided by protuberances  100  and  102 . 
       FIGS. 10-12  are views of the self-retained slider contact pin  92 , in which  FIG. 10  is a sectional view taken along section line  10 - 10  of  FIG. 9 ,  FIG. 11  is a perspective view of the self-retained slider contact pin  92  with the bias spring  98  removed, and a  FIG. 12  is an exploded view of the first contact  94  separated from the second contact  16 . The first contact  94  and the second contact  96  of the slider contact pin  92  are slidably interlocked in the telescoping arrangement by means of two longitudinally spaced apart fingers  116  and  130  which extend from the first contact  92  through respective openings  120  and  134  in the second contact  96 . The fingers  116  and  130  are preferably configured to align in registration with the openings  120  and  134 . The first contact  94  and the second contact  96  are each formed of respective strips of conductive material which preferably are formed by coining, or stamping, to have a length, a width and a thickness. Preferably the length is longer than the width is wide, and the thickness is nominal as compared to the width by an order of magnitude of at least four times the width. However, although length is generally thought of longer than width it may be determined in the opposite order in some circumstances contemplated by the present disclosure. The first contact  94  and the second contact  96  have widths defining flat surfaces  124  and  126 , respectively, which will slidably engage in electrical contact providing mating surface areas with electric continuity between the contacts  94  and  96 . 
     The first contact  94  is stamped from a strip of conductive material which preferably has an elongate body with a longitudinal axis  104 , forming a notch  118  and a notch  132  where the finger  116  and the finger  130 , respectively, are stamped from the width of the strip of conductive material. The finger  116  and the finger  130  are each preferably formed of an elongate section of conductive material having compliance which are stamped from the strip of material and each extend with first a base  138 , then an intermediate section  139 , and then a terminal end tip  140 . The second contact  96  is coined from a second strip of conductive material preferably having an elongate body with a longitudinal axis  106 . An opening  120  and an opening  134  are stamped into the second contact  96 , spaced apart along the longitudinal axis  106 . The openings  120  and  134  provide two spaced apart windows for passing respective ones of the fingers  116  and  130  through the second contact  96 . The channels  122  and  136  are also stamped into the second contact  96 , preferably adjacent to respective ones of the openings  120  and  134 . The channels  122  and  136  provide guides for receiving the terminal end tips  140  of the fingers  116  and  130  and guiding the terminal end tips  140  of the fingers  116 ,  130  as the first contact  94  and the second contact  96  slidably move relative to one another. The base  138  of the fingers  116  and  130  will generally be disposed within and engage the edges of respective ones of the openings  120  and  134  in the second contact  96 , which together with the compliance of the terminal end tips  140  engaging with respective ones of the channels  122  and  136  provide that the first contact  94  and the second contact  96  are self-retaining when assembled with the bias spring  98 . As compared to contact pins with only one finger, the two fingers  116  and  130  of the third contact pin  92  are spaced apart along the longitudinal axes  104 ,  106  to further secure the first contact  94  and the second contact  96  against relative rotation about an axis extending perpendicular to the preferably parallel longitudinal axes  104 ,  106 . 
       FIG. 13  is a perspective view of a fourth self-retained slider contact pin  142 . The contact pin  142  preferably has three separate components: the first contact  144 , a second contact  146 , and a bias spring  148 . The first contact  144  and the second contact  146  are configured to slidably fit together and interlock in a telescoping arrangement such that the overall combined length of the first contact  144  and the second contact  146  will expand and contract. The bias spring  148  is secured to engage between the first contact  144  and the second contact  146  to urge the first contact  144  and the second contact  146  to move apart, extending the overall combined length and providing compliance for electrically connecting between circuit conductors. Preferably the bias spring  148  is provided by a coil spring which is captured between tabs  158  and  160  of respective ones of the first contact  144  and the second contact  146 . The tab  158  has a shoulder  162  and the tab  160  has a shoulder  164  which engage against opposite terminal ends of the bias spring  148 . The respective end tips of the first contact pin  144  and the second contact pin  146  are provided by protuberances  150  and  152 . 
       FIGS. 14-16  are views of the self-retained slider contact pin  142 , in which  FIG. 14  is a sectional view taken along section line  14 - 14  of  FIG. 13 ,  FIG. 15  is a perspective view of the self-retained slider contact pin  142  with the bias spring  148  removed, and  FIG. 16  is an exploded view of the first contact  144  separated from the second contact  146 . The first contact  144  and the second contact  146  of the slider contact pin  142  are slidably interlocked in the telescoping arrangement by means of two longitudinally spaced apart fingers  166  and  180  which extend from the first contact  142  through respective openings  170  and  184  in the second contact  146 . The fingers  166  and  180  are preferably configured to align in registration with the openings  170  and  184 . The first contact  144  and the second contact  146  are each formed of respective strips of conductive material which preferably are formed by coining, or stamping, to have a length, a width and a thickness. Preferably the length is longer than the width is wide, and the thickness is nominal as compared to the width by an order of magnitude of at least four times the width. However, although length is generally thought of longer than width it may be determined in the opposite order in some circumstances contemplated by the present disclosure. The first contact  94  and the second contact  146  have widths defining flat surfaces  174  and  176 , respectively, which will slidably engage in electrical contact providing mating surface areas with electric continuity between the contacts  144  and  146 . 
     The first contact  144  is stamped from a strip of conductive material which preferably has an elongate body with a longitudinal axis  154 , forming a notch  168  and a notch  182  where the finger  166  and the finger  180 , respectively, are stamped from the width of the strip of conductive material. The finger  166  and the finger  180  are each preferably formed of an elongate section of conductive material having compliance which are stamped from the strip of material and each extend with first a base  188 , then an intermediate section  189 , and then a terminal end tip  190 . The second contact  146  is coined from a second strip of conductive material preferably having an elongate body with a longitudinal axis  156 . An opening  170  and an opening  184  are stamped into the second contact  146 , spaced apart along the longitudinal axis  156 . The openings  170  and  184  provide two spaced apart windows for passing respective ones of the fingers  166  and  180  through the second contact  146 . The channels  172  and  186  are also stamped into the second contact  146 , preferably adjacent to respective ones of the openings  170  and  184 . The channels  172  and  186  provide guides for receiving terminal end tips  190  of the fingers  166  and  180  and guiding the terminal end tips  190  of the fingers  166 ,  180  as the first contact  144  and the second contact  146  slidably move relative to one another. The base  188  of the fingers  166  and  180  will generally be disposed within and engage the edges of respective ones of the openings  170  and  184  in the second contact  146 , which together with the compliance of the terminal end tips  190  engaging with respective ones of the channels  172  and  186  provide that the first contact  144  and the second contact  146  are self-retaining when assembled with the bias spring  148 . As compared to contact pins with only one finger, the two fingers  166  and  180  of the fourth contact pin  142  are spaced apart along the longitudinal axes  154 ,  156  to further secure the first contact  144  and the second contact  146  against relative rotation about an axis extending perpendicular to the preferably parallel longitudinal axes  154 ,  166 . 
       FIG. 17  is a perspective view of a fifth self-retained slider contact pin  192 . The contact pin  192  preferably has three separate components: the first contact  194 , a second contact  196 , and a bias spring  198 . The first contact  194  and the second contact  196  are configured to slidably fit together and interlock in a telescoping arrangement such that the overall combined length of the first contact  194  and the second contact  196  will expand and contract. The bias spring  198  is secured to engage between the first contact  194  and the second contact  196  to urge the first contact  194  and the second contact  196  to move apart, extending the overall combined length and providing compliance for electrically connecting between circuit conductors. Preferably the bias spring  198  is provided by a coil spring which is captured between tabs  208  and  210  of respective ones of the first contact  194  and the second contact  196 . The tab  208  has a shoulder  212  and the tab  210  has a shoulder  214  which engage against opposite terminal ends of the bias spring  198 . The respective end tips of the first contact pin  194  and the second contact pin  196  are provided by protuberances  200  and  202 . 
       FIGS. 18-20  are views of the self-retained slider contact pin  192 , in which  FIG. 18  is a sectional view taken along section line  18 - 18  of  FIG. 17 ,  FIG. 19  is a perspective view of the self-retained slider contact pin  192  with the bias spring  198  removed, and  FIG. 20  is an exploded view of the first contact  194  separated from the second contact  196 . The first contact  194  and the second contact  196  of the slider contact pin  192  are slidably interlocked in the telescoping arrangement by means of a finger  216  which extends from a terminal end of the first contact  192 , and through an opening  220  in the second contact  196 . The first contact  194  and the second contact  196  are each formed of respective strips of conductive material which preferably are formed by coining, or stamping, to have a length, a width and a thickness. Preferably the length is longer than the width is wide, and the thickness is nominal as compared to the width by an order of magnitude of at least four times the width. However, although length is generally thought of longer than width it may be determined in the opposite order in some circumstances contemplated by the present disclosure. The first contact  194  and the second contact  196  have widths defining flat surfaces  224  and  226 , respectively, which will slidably engage in electrical contact providing mating surface areas with electric continuity between the contacts  194  and  196 . 
     The first contact  194  is stamped from a strip of conductive material which preferably has an elongate body with a longitudinal axis  204 , forming a notch  218  where the finger  216  is pressed from the width of the strip of conductive material, rolled from a longitudinal edge of the first contact  194 . The finger  216  is preferably an elongate section of conductive material having compliance which is stamped and then rolled from an edge of the strip of material and extends with first a base  228 , then an intermediate section  229 , and then a terminal end tip  230 . The second contact  196  is coined from a second strip of conductive material preferably having an elongate body with a longitudinal axis  206 . An opening  220  is stamped into the second contact  196  and provides a window for passing the finger  216  through the second contact  196 . A channel  222  is also stamped into the second contact, preferably adjacent to the opening  220 . The channel  222  provides a guide for receiving a terminal end tip  230  of the finger  216  and guiding the terminal end tip  230  of the finger  26  as the first contact  194  and the second contact  196  slidably move relative to one another. The base  228  of the finger  216  will generally be disposed within and engage the edges of the opening  210  in the second contact  196 , which together with the compliance of the terminal end tip  230  engaging with the channel  222  provide that the first contact  194  and the second contact  196  are self-retaining when assembled with the bias spring  198 . 
     The present disclosure provides advantages of compliant contact pin which is formed of coined or stamped contacts. The contact pin is self-retaining and provides slidably engaged contact areas between the first contact and the second contact. Two contact members are secured together by one or more fingers which are stamped from the contact members and extend through windows formed into the other contact member. The two contact members engage in a surface area contact. A bias spring urges compliance with mating parts. 
     Although the preferred embodiment has been described in detail, it should be understood that various changes, substitutions and alterations can be made therein without departing from the spirit and scope of the invention as defined by the appended claims.