Patent Publication Number: US-6220899-B1

Title: Electrical connector jack for securely holding a plug

Description:
This application is a continuation of PCT/JP99/02598 filed May 19, 1999, published as WO 99/62148 on Dec. 2, 1999. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to an electrical connector jack. More specifically, it relates to a jack with a plug connecting sleeve spring disposed in the sleeve portion of the jack. 
     In the prior art, a conventional jack has a cylindrical sleeve portion with an opening into which a plug is inserted. The plug has a collar which fits over the sleeve electrically and mechanically connecting the sleeve to the collar. 
     A jack using the above plug and collar contact structure is disclosed in Japanese Unexamined Patent Publication No. 1-73899. The disclosed jack has a cylindrical collar which makes contact with a sleeve portion of a plug,. In order to ensure good electrical and physical contact, the sleeve portion must snugly fit against the collar. This requires accurate manufacturing, increasing the cost of producing the jack. Also, it is more difficult to ensure a snug fit when the jack miniaturized. In a cylindrical jack using the above disclosed snug fit connection, more material is required. This increases the weight of the jack and makes it more difficult to miniaturize. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a jack that solves the problems of the prior art. 
     It is another object of the present invention to provide a jack that does not require the dimensional accuracy of the prior art. 
     It is yet another object of the present invention to provide a jack which can be easily assembled. 
     It is another object of the present invention to provide a jack that can be miniaturized while maintaining good electrical characteristics. 
     Briefly stated, the present invention provides a connecting sleeve spring resiliently mounted in a connecting sleeve of an electrical connecting jack. The connecting sleeve spring has a arcuate sinusoidal-like side profile, with its two ends curving in a direction opposite the curve of a center contact portion. The center portion has an inwardly angled tongue. When a plug having a collar is inserted into the electrical connecting jack, the collar comes in contact with the tongue and pushes the central contact portion inward, thus forcing the two ends of the connecting sleeve spring to move outward. The two ends press against the inner periphery of the collar. In this way, the collar makes contact with the connecting sleeve spring at three points; the two ends and the center contact portion. This three point contact arrangement firmly holds and electrically connects the plug, to the jack even if there is a gap between the collar and sleeve. The electrical connecting jack also includes a housing with a plurality of contact spring openings. A plurality of contact springs resiliently fit in these openings, electrically connecting the springs to the plug. 
     According to an embodiment of the invention, there is provided an electrical connector jack comprising: a housing having a sleeve portion; the housing has a cavity axially disposed therein; the sleeve portion has a centrally disposed plug insertion opening communicating with the cavity whereby a plug is insertable therein; the plug has a collar axially disposed at one end; a plug connecting sleeve spring in the sleeve portion; means for resiliently holding the plug connecting sleeve spring in the sleeve portion; the plug connecting sleeve spring being generally arcuate; a central contact portion on the plug connecting sleeve spring; the plug connecting sleeve spring has a diameter centered on a longitudinal axis of the jack; a tongue on the central contact portion; the tongue is angled centrally inwards whereby the collar is partially aligned with the plug connecting sleeve spring when the collar is pushed against the tongue; the plug connecting sleeve spring has a first support piece at one end; and the plug connecting sleeve spring also has a second support piece at an other end whereby when the collar is fitted against the plug connecting sleeve spring, the central contact portion deforms inward towards the longitudinal axis forcing the first and second support pieces to move outward contacting the collar, firmly holding and electrically connecting the plug to the sleeve portion. 
     A-According to another embodiment of the invention, there is provided a connecting sleeve having a first diameter disposed on an electrical connector jack comprising: a plug insertion opening centrally disposed in the connecting sleeve the connecting sleeve has a first convex portion and a second convex portion; the connecting sleeve also has concave portion between the first and second convex portions; a connecting sleeve spring having a first support end and a second support end; the connecting sleeve spring has a central contact portion having a second diameter; the second diameter is smaller than the first diameter; the first support end has a third diameter; the second support has a fourth diameter; the third and fourth diameters are centered in a direction opposite the second diameters; the connecting sleeve spring is radially disposed in the connecting sleeve whereby the first support end fits in the first convex portion and the second support end fits in the second convex portion, resiliently holding the connecting sleeve spring in the connecting sleeve while leaving a gap between the central contact portion and the concave portion; a tongue on an end of the central contact portion facing the concave portion; and the tongue is angled inwards towards the plug insertion opening whereby a collar attached to a plug makes contact with the tongue, moving the central contact portion inward towards the gap, thus forcing the first and second support ends outward towards an inside periphery of the collar, firmly holding and electrically connecting the plug to the electrical connector jack. 
     According to another embodiment of the invention, there is provided an electrical connector jack comprising: a plug having an axially disposed collar; a housing having a plurality of contact spring openings therein; a plug receiving cavity axially disposed within the housing; a connecting sleeve having a first diameter on a plug insertion end of the housing; a plug insertion opening cent rally disposed on the plug insertion end of the plug receiving cavity; a plurality of contact springs resiliently affixed to the housing whereby each one of the plurality of contact springs makes resilient contact with the plug through one of the plurality of contact spring openings when the plug is inserted within the housing; the connecting sleeve has a first convex portion and a second convex portion; the connecting sleeve also has concave portion between the first and second convex portions; a connecting sleeve spring having a first support end and a second support end; the connecting sleeve spring has a central contact portion having a second diameter; the second diameter is smaller than the first diameter; the first support end has a third diameter; the second support has a fourth diameter; the third and fourth diameters are centered in a direction opposite the first and second diameters; the connecting sleeve spring is radially disposed in the connecting sleeve whereby the first support end fits in the first convex portion and the second support end fits in the second convex portion resiliently holding the connecting sleeve spring in the connecting sleeve, while leaving a gap between the central contact portion and the concave portion; a tongue on the plug insertion end of the central contact portion; and the tongue is angled inwards towards the concave portion whereby when the plug is inserted in the plug receiving cavity, the collar makes contact with the tongue moving the central contact portion inward towards the gap thus forcing the first and second support ends outward towards an inside periphery of the collar, firmly holding and electrically connecting the plug to the electrical connector jack. 
     According to yet another embodiment of the invention, there is provided a connecting sleeve for installation in an electrical connector jack comprising: a plug connecting sleeve spring resiliently lodged in a channel of the connecting sleeve; a terminal on the plug connecting sleeve spring; the terminal electrically connectable to an external contact; a tongue on a central portion of the plug connecting sleeve spring; the central portion being positioned for resiliently urged contact with a connecting portion of the plug inserted into the electrical connector jack; and the resiliently urged contact, forcing the central portion to flex while urging both ends of the plug connecting sleeve spring in an opposite direction toward a perimeter surface of the connecting portion, thereby firmly holding and electrically connecting the connecting portion to the connecting sleeve. 
     A jack according to the present invention includes a sleeve spring with a contact disposed on a part of the sleeve portion that faces outward. Accordingly, even if the sleeve spring is reduced in size, it is easy to operate. Assembly is also simplified because it is produced simply by punching and bending sheet metal. 
     Further, since the sleeve spring is arranged to have a three-points-contact structure which applies a resilient force equal to the force applied to deform a contact portion, firmly holding the plug to the jack. This structure does not require that the dimensions of the sleeve and collar be as dimensionally precise as is required by the prior art. 
     The above, and other objects, features and advantages of the present invention will become apparent from the following description read in conjunction with the accompanying drawings, in which like reference numerals designate the same elements. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective view of a jack according to the present invention. 
     FIG. 2 is an enlarged perspective view of the main portion of the first sleeve spring (plug connecting sleeve spring) in an engaged state disposed along the sleeve portion of the jack. 
     FIG. 3 is an end view of the first sleeve spring (plug connecting sleeve spring) engaged with the sleeve portion. 
     FIG. 4 is a side view of the jack. 
     FIG. 5 is a sectional side view showing a plug inserted into the jack. 
     FIG. 6 is another side sectional view showing a plug inserted into the jack. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1, a housing  10  includes a first sleeve spring  13  (also hereinafter referred to simply as sleeve spring  13 ) formed of a conductive material. A second sleeve spring  14  is disposed on an opposite side of housing  10 . A chip spring  15  and a second terminal  16  are disposed along a right rear section of housing  10 . A ring spring  17  and a first terminal  18  are disposed along a left rear section of housing  10 . Housing  10  is substantially a rectangular-prism with a plug inserting hole  11  disposed therein. A first sleeve spring  13  is lockingly inserted in a body engaging portion  25  disposed along a left wall surface of housing  10 . First sleeve spring  13  also lockingly engages a sleeve portion  12 . Second sleeve spring  14  is lockingly inserted in a second sleeve engaging portion  21  disposed along a right wall surface of housing  10 . Chip spring is lockingly inserted in a chip spring engaging portion  23  of housing  10  disposed along a rear right wall surface of housing  10 . First terminal  1   8  is inserted from the rear side of ring spring  17 . This provides the option for a three-point contact on a plug  45  when plug  45  is inserted in housing  10 . One contact point optionally is provided by second sleeve spring  14 , and the other two are optionally provided by chip spring  15  and ring spring  17 . This arrangement provides a plurality of plug connection springs. 
     Referring to FIGS. 1 and 6, housing  10  includes sleeve portion  12 , disposed along a front surface side thereof with plug inserting hole  11  disposed therein. A plug  45  is insertable in plug insertion hole  11 . Plug insertion hole  11  is integrally formed with a body portion  19 . Housing  10  includes a first sleeve spring engaging portion  20  and second sleeve spring engaging portion  21 . Also disposed on housing  10  is a ring spring engaging portion  22  and chip spring engaging, portion  23 . First sleeve spring engaging portion  20  is disposed on a side surface of body portion  19 . Second sleeve spring engaging portion  21  is disposed on the side surface of body portion  19  opposite to first sleeve spring, engaging portion  20 . 
     Ring spring engaging portion  22  is disposed at the rear end of body portion  19  on first sleeve spring engaging portion  20  side. Ring spring  17  is lockingly engaged therewith. Chip spring engaging portion  23  is disposed on the side surface of body portion  19  opposite to ring spring engaging portion  22 . Chip spring  15  is lockingly engaged therewith. 
     Referring now to FIGS. 1,  2  and  3 , first sleeve spring engaging portion  20  includes a support piece engaging portion  24  and body engaging portion  25 . Support piece engaging portion  24  is disposed along the outer periphery of plug inserting hole  11 . Body engaging portion  25  is integrally formed with support piece engaging portion  24 . 
     Support piece engaging portion  24  includes a concave portion  26 , which is formed by denting a part of sleeve portion  12  along the curved peripheral surface. Convex portions  27  are disposed at both ends of concave portion  26 . The central edge of concave portion  26  is chamfered. 
     First sleeve spring  13  is made by punching and forming a sheet member forming a plug contact portion  28 , a body portion  29  and a terminal portion  30 . 
     Plug contact portion  28  is formed by bending the forward extreme end of the sheet member in an arc. Body portion  29  is punched and formed along the rear end of the sheet member. Terminal portion  30  is formed by bending the sheet member at a lower end of body portion  29  outward at right angles. The diameter of plug contact portion  28  is smaller than the diameter of concave portion  26  so that a gap is made when they are engaged with each other. 
     Plug contact portion  28  is composed of a tongue piece  31  and support pieces  32 . Tongue piece  31  is centrally formed along the front edge of plug contact portion  28 . Tongue piece  31  is chamfered and slightly bent towards the central axis of plug insertion hole  11 . Support pieces  32  are formed by bending both ends of plug contact portion  28  away from the central axis of plug insertion hole  11 . 
     Referring now to FIGS. 1-3 and  6 , when a collar  46  of a plug  45  fits over sleeve portion  12  and first sleeve spring  13 , plug contact piece  28  is deformed inwards towards concave portion  26 . The deflection of contact piece  28  forces support pieces  32  outward towards the inner perimeter of collar  46 , holding plug  45  snugly. Because support pieces  32  make contact with the inner perimeter of collar  46  in two places and an opposite edge of sleeve portion  12  is also in contact with collar  46 , three contact points are provided on collar  46  when plug  45  is inserted in plug inserting hole  11 . Contact portion  28  is elastically deformed by the action of inserting plug  45 . Collar  46  first makes contact with the chamfered edge of tongue piece  31  forcing plug contact portion  28  to deflect inward, thus forcing support pieces  32  to move outward, firmly holding plug  45 . It is not necessary for support pieces  32  to contact collar  46  since the elastic resilience of contact portion  28  is sufficient to securely hold plug  45  in place. 
     Referring to FIGS.  1  and  3 - 6 , second sleeve spring  14  includes a contact portion  33  and a terminal portion  34 . Contact portion  33  is formed by bending a sheet member at right angles and obliquely extending contact portion  33  toward the front of body portion  19 . Terminal portion  34  is formed on the opposite side of contact portion  33  and connectable to an external part. Second sleeve spring  14  is lockingly engaged with second sleeve spring engaging portion  21 . Contact portion  33  projects from atop portion of housing  10  down inside the interior space of plug insertion hole  11 . 
     Ring spring  17  is composed of a contact portion  35  and a tongue-shaped terminal portion  36 . Contact portion  35  is generally rectangular with a tapered end bent to form a contact. Tongue-shaped terminal portion  36  is formed by bending a tab extending from a side of ring spring  17  at a right angle. Ring spring  17  is inserted into ring spring engaging portion  22  disposed at the rear end of the housing  10 . Ring spring  17  is lockingly engaged with spring engaging portion  22  and positioned so that contact portion  35  projects from a left side portion of housing  10  inside the interior space of plug insertion hole  11 . 
     First terminal  18  is composed of a contact portion  37  and a terminal portion  38 . First terminal is generally rectangular with a cutout portion. Terminal portion  38  is formed by bending a tab disposed along a rear end of first terminal  18  at a right angle. First terminal  18  is inserted from the rear end into housing  10  with contact portion  37  lockingly engaging with ring spring  17 . First terminal  18  is lockingly engaged with housing  10  so that contact portion  37  is in contact with a back surface of contact portion  35  of ring spring  17 . 
     Chip spring  15  is inserted from the rear end of housing  10  and lockingly engaged therewith. Chip spring  15  is generally rectangular and composed of a contact portion  39  and a terminal portion  40 . Chip spring  15  is cut and bent to form contact portion  39 . Contact portion  39  is bent inward so that it projects into the interior space of plug insertion hole  11 . Terminal portion  40  is formed by bending a rear portion of chip spring  15  at a right angle. Contact portion  39  has an apex at an intermediate portion thereof and is tapered from the apex toward the free end which is fork-shaped. Chip spring  15  is inserted into chip spring engaging portion  23  of housing  10  and lockingly engaged therewith. 
     Second terminal  16  is composed of a fork-shaped contact portion  41  and a terminal portion  42 . Contact portion  41  is formed by cutting out an arc in an end of second terminal  16 . Terminal portion  42  is formed by bending the base end second terminal  16 . Second terminal  16  is lockingly inserted into chip spring  15  from the rear end of housing  10 . Contact portion  41  comes into contact with chip spring  15  in such a manner that the slender free end of contact portion  39  of chip spring  15  is held by fork-shaped contact portion  41 . That is, second terminal  16  is in electrical contact with chip spring  15  when plug  45  is inserted in plug insertion hole  11 . 
     When first sleeve spring  13  is lockingly engaged with first sleeve spring engaging portion  20 , body portion  29  is engaged with body engaging portion  25 . Next, support pieces  32  are fitted between convex portions  27  and concave portion  26  of support piece engaging, portion  24  and push-fitted therein. This lockingly engages first sleeve spring  1 I 3  with housing  10  at three points with tongue piece  31  disposed therein. 
     When plug  45  is inserted into first sleeve spring  13 , which has been lockingly engaged as described above, from the outside, connecting piece  46  makes contact with the end of tongue piece  31 . Then, tongue piece  31  deflects and this force is transmitted to support pieces  32 . As a result, the diameter of plug contact portion  28  increases by moving toward the gap formed between concave portion  26 . Since collar  46  of plug  45  is urged against sleeve portion and plug contact portion  28  by the action of support pieces  32 , connecting piece  46  is firmly held against plug contact portion  28 . 
     Further, when connecting piece  46  of plug  45  presses against plug contact portion  28 , support pieces  32  move apart in an outward direction causing connecting piece  46  to be firmly held in contact with plug contact portion  28 . That is, collar  46  is in contact with elastic plug contact portion  28  through a so-called three-points contact by being pressed by both support pieces  32  which have moved outward. This provides a stable electrical and mechanical contact even when miniaturized. 
     Having described preferred embodiments of the invention with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims.