Abstract:
A connector including a first connector element and a second connector element that are coupled into a single unit, in which the first connector element has an engagement projection that projects interior of the first connector element and extends in the direction of the depth of the first connector element so that the front end of the engagement projection is spacedly apart from the front edge of the first connector element, and the second connector element is formed with an engagement slit that extends in the direction of depth of the second connector element and engages with the engagement projection of the first connector element.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a connector and more particularly to an electrical connector used in, for instance, small size electrical appliances. 
     2. Prior Art 
     In for instance, computer related electronic appliances, the electrical connections including connections to an AC adapter, to interfaces, etc. are made in many different ways. Such electrical connections are typically made by connectors that substantially comprise a receptacle (female) side connector element and a plug (male) side connector element that is brought into the receptacle side connector and coupled thereto for making electrical connection in between so that pin-shaped electrodes installed in the connector elements are connected. 
     More specifically, connectors typically include in their metal shells a plurality of pins (or terminals) that are arranged in parallel in their longitudinal directions and positionally secured by insulator material such as polyamide, LCP (liquid crystalline polymer), etc. The pins in the receptacle and plug side connector elements are spacedly arranged side by side in the direction in which the connector elements are mated together. 
     Upon making connection of the plug side connector element into the receptacle side connector element, it is necessary that respective pins in two connector elements be aligned to be on a straight line. In other words, it is necessary to avoid the connector elements from being oblique to each other when they are brought together at their front edges for connection. If the plug side connector element in an oblique posture with reference to the receptacle side connector element, as shown in FIG. 10, is pushed into the receptacle side connector element, an irregular pin connection is made (as at  100 ) as seen from the enlarged view shown in the circle in FIG. 10, and this would cause several problems including short-circuiting. 
     In addition, when the plug side connector element is connected to the receptacle connector element in a slanted posture (which can easily occur when there is size differences between the receptacle and plug side connector elements), removing of the plug side connector element from the receptacle side connector element is not easily done and occasionally requires forcible and repeated twists on the shell of the plug side connector element This would cause damage to the pins and the shells of both connector elements. 
     Thus, though pin alignment is essential when connection is made between the two connector elements, such a pin alignment is not obtained easily and this difficulty can occur often when the connector is small in size and used in small size electrical devices such as a personal digital assistance (PDA), digital cameras, camcorders, etc. 
     SUMMARY OF THE INVENTION 
     Accordingly, the object of the present invention is to provide an electrical connector that allows accurate and secure connections or coupling between connector elements to be made easily without causing pin or electrode misalignment. 
     The above object is accomplished by a unique structure of the present invention for a connector that comprises a first connector element and a second connector element that are coupled together when the second connector element is fitted in the first connector element, and in the present invention: 
     the first connector element is formed with an engagement projection that extends in the direction of the depth of the first connector element, the front end of the engagement projection being spacedly apart from the front edge of the first connector element; and 
     the second connector element is formed with an engagement slit or slot that extends in the direction of the depth of the second connector element so that the engagement slit receives therein the engagement projection of first connector element when the first and second connector elements are connected. 
     With the structure above, upon connecting the second connector element to the first connector element, the front end of the engagement slit of the second connector element engages with the engagement projection of the fist connecting element after the front end of the engagement slit has advanced the distance between the front edge of the first connector element and the front end of the engagement projection, and then the second connector element is pushed all the way to back of the first connector element in the depth of the first connector element while being guided by the engagement slit engaging with the engagement projection. Accordingly, even when the second connector element is obliquely pushed into the first connector element at the initial stage of coupling process, such oblique posture is corrected by the engagement projection of the first connector element as the second connector element is pushed and advanced to the back of the first connector element, and a connection between the first and second connector elements with the pins (electrodes) inside both of them being aligned straight can be made assuredly. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the first connector body (first connector element) of the connector according to the present invention; 
     FIG. 2 is a perspective view of the second connector body (second connector element) of the connector according to the present invention; 
     FIG. 3 is a schematic top view of the first connector body, 
     FIG. 4 schematically shows the cross section of the first connector body taken along the line  44  in FIG. 3; 
     FIG. 5 is a schematic top view of the second connector body, 
     FIG. 6 schematically shows the cross section of the second connector body taken along the line  6 — 6  in FIG. 5; 
     FIG. 7 illustrates the second connector body which is combined with a plug assembly, 
     FIG. 8 illustrates the manner of connecting the second connector body to the first connector body, 
     FIG. 9 illustrates the first connector body to which the second connector body (not seen) is connected; and 
     FIG. 10 illustrates the manner of oblique connection of the first and second connector elements in prior art connector. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The connector of the present invention is comprised of a first connector body  20  (a receptacle side connector element) and a second connector body  40  (a plug side connector element). 
     As seen from FIGS. 1 and 2, the first and second connector bodies  20  and  40  comprise respectively a relatively flat box shape shell  22  and  42  made of a metal and include therein a plurality of pins or elongated electrodes, which are collectively referred to by the reference numerals  24  and  44  respectively, and an insulating material (not shown) is filled therein so as to positionally secure the pins  24  and  44 . 
     The shell  22  of the first connector body  20  comprises, as best seen from FIG. 4, a top shell plate  22 A and a bottom shell plate  22 B as well as side shell plates  22 C, thus forming a box shape that has a predetermined depth  22 D (see FIG. 3) that extends from the front edge  20 A to the rear edge  20 B of the first connector body  20 . The pins  24  of the first connector body  20  are arranged parallel to the direction of the depth  22 D. 
     The shell  22  of the first connector  20  is formed in its top shell plate  22 A with engagement projections  30 . Each of the projections  30  is formed by cutting the top shell plate  22 A in an angled C shape, and the resulting tongue pieces  22 E are bent inward toward the interior of the shell  22 . The tongue pieces  22 E are in the shape of elongated parts of the shell  22  that extend in the direction of the depth  22 D of the first connector body  20 , and they are parallel to the side shell plates  22 C of the first connector body  20  or to the side edges  22 A′ of the top shell plate  22 A. 
     The tongue pieces  22 E are bent at locations of distance  22 W from the side shell plates  22 C or from the side edges  22 A′ of the first connector body  20  to make the engagement projections  30 . The engagement projections  30  are provided with a space of a distance L apart from the front edge  20 A of the first connector body  20 . In other words, the front ends  32  of the engagement projections  30  are spaced apart from the front edge  20 A of the first connector body  20 . The engagement projections  30  have a length  30 L which is, in the shown embodiment, about two third the depth  22 D of the first connector body  20 . 
     On the other hand, the shell  42  of the second connector body  40  comprises, as best seen from FIG. 6, a top shell plate  42 A and a bottom shall plate  42 B as well as side shell plates  42 C, thus forming a box shape with a predetermined depth  42 D (see FIG. 6) that extends from the front edge  40 A to the rear edge  40 B of the second connector body  40 . The overall size of the shell  42  of the second connector  42  is slightly smaller than the shell  22  of the first connector body  20  so that the second connector body  40  is fitted in the first connector body  20  from the front side of the first connector body  20 . The pins  44  of the second connector body  40  are arranged so be parallel to the direction of the depth  42 D. 
     The shell  42  of the second connector body  40  is formed in its top shell plate  42 A with engagement slits  50 . Each of the engagement slits  50  is formed by cutting away parts of the top shell plate  42 A linearly so that the engagement slits  50  are parallel to and adjacent to the side plates  42 C or to side edges  42 A′ of the top shell plate  42 A. An alternate construction would be to mold the slits  50  into the shell  42  when the shell  42  is made. The engagement slits  50  are provided so as to extend in the direction of depth  42 D of the shell  42  of the second connector body  40 . In other words, the front end ends  52  of the engagement slits  50  are on the front edge  40 A of the second connector body  40 . The engagement slits  50  have a length  50 L which is, in the shown embodiment, about two thirds of the depth  42 D of the second connector body  40  and is slightly larger in length than the engagement projections  30  of the first connector body  20 . 
     The engagement slits  50  are opened at locations of distance  42 W from the side shell plates  42 C or from the side edges  42 A′ of the top shell plate  42 A of the second connector body  40 , the distance  42 W being substantially the same as the distance  22 W of the engagement projections  30  of the first connector body  20 . Thus, the engagement slits  50  positionally correspond to the engagement projections  30  of the first connector body  20 . The width W of the engagement slits  50  is substantially the same as (or slightly larger than) the thickness of the tongue pieces  22 E (engagement projections  30 ) which is the thickness of the metal material of the shell  22  of the first connector body  20 . 
     The reference numerals  60  shown in FIG. 2 are raised springy holders formed by notching the top shell plate  42 A of the second connector body  40  and raised outwardly. 
     The first and second connector bodies  20  and  40  structured as described above are connected by way of mating together at the front ends of the shells  22  and  42 . 
     More specifically, as shown in FIG. 7, the second connector body  40 , which is attached at its rear edge  40 B to, typically, a plug assembly  60  that is connected to, for instance, an electrical cable (not shown), is held by hand, and then it is brought to the vicinity of the first connector body  20  which is installed in a casing body of, for instance, a PDA (not shown). 
     The front edge  40 A of the second connector body  40 , which is a plug side connector element, is set so as to face the front edge  20 A of the first connector body  20 , which is a receptacle side connector element, so that the first and second connector bodies  20  and  40  are aligned in the direction of the depth thereof (which brings an alignment of the pins  24  and  44  installed in such connector bodies  20  and  40 ). In this positioning, since the distances  22 W and  42 W of the first and second connector bodies  20  and  40  are substantially equal, the engagement projections  30  of the first connector body  20  and the engagement slits  50  of the second connector body  40  are also aligned on imaginary straight lines. 
     Then, the second connector body  40  is pushed into the first connector body  20  as shown by arrow in FIG.  8 . During the initial pushing movement, the outer surfaces of the shell  42  of the second connector body  40  are guided by the inner surfaces of the shells  22  of the first connector body  20 . After advancing the distance L which is the distance from the front edge  20 A to the front ends  32  of the engagement projections  30  in the first connector body  20 , the engagement slits  50  of the second connector body  40  come into engagement with the engagement projections  30  of the first connector body  20 . As a result, the sliding movement of the second connector body  40  in the depth  22 D of and toward the rear edge  20 B of the first connector body  20  is guided by the engagement projections  30 . The second connector body  40  is thus pushed into the first connector body  20  straight with the pins inside both connector bodies aligned straight as well and connected to the first connector body  20  (see FIG. 9, in which the second connector body  40  is unseen since it is inside the first connector body  20 ). The second connector body  40  is held inside the first connector body  20  by the raised springy holders  60  that press against the inside surface of the top shell plate  22 A of the first connector body  20 . 
     The width W of each engagement slit  50  is substantially the same as (or slightly larger than) the thickness of the engagement projection  30 , and thus the engagement projections  30  have substantially no space for play in the direction perpendicular to the direction of the length of the engagement slits  50  or to the direction of the connecting direction of the first and second connector bodies  20  and  40 . Accordingly, the engagement slits  50  of the second connector body  40  make no lateral movements during the sliding movement, keeping the straight alignment obtained by the engaged engagement projections  30  and engagement slits  50 . 
     As a result, even when the second connector body  40  is slanted with reference to the first connector body  20  during the initial connecting stage, such a slanted positional relationship is automatically corrected to a straight relationship as the second connector body  40  is pushed into deep in the first connector body  20 , and a snug and secure engagement of the first and second connector bodies  20  and  40  is accomplished, and pins  24  and  44  of the first and second connector bodies  20  and  40  are connected properly. The engagement projections  30  and the engagement slits  50  are formed near the side edges  22 A′ and  42 A′ of the first and second connector bodies  20  and  40 , respectively; accordingly, the connection of the connector bodies  20  and  40  can be made in a stable fashion, and a separation of the connected connecting bodies can be made easily.