1. Field of the Invention
The invention relates to a connector.
2. Description of the Related Art
Japanese Unexamined Patent Publication No. 2006-19228 relates to a circuit board connector with a housing. Through holes penetrate a base wall of the housing in a thickness direction and long narrow terminal fittings are inserted through the base wall. Each terminal fitting includes a press-in portion to be pressed into the through hole and a projection that projects out in width direction behind the press-in portion for limiting the penetration of the terminal fitting. Press-in areas are formed in middle parts of the through holes in forward and backward directions and receive the press-in portions of the terminal fittings. Recesses are formed in rear parts of the through holes. Front ends of the recesses and the rear ends of the press-in areas are connected via steps. Further, each recess has an inclined portion narrowed in an inserting direction of the terminal fitting from the rear end of the base wall for guiding the insertion of the terminal fitting.
The projections fit loosely in the recesses due to the presence of the inclined portions. Thus, a force for holding the terminal fitting in the base wall depends on the size of pressing margins of the press-in portions engageable with the press-in areas of the through holes. However, if the pressing margins are large, the insertion resistance of the terminal fittings increases to worsen operability. If the pressing margins are small, the terminal fittings are likely to misalign.
The invention was developed in view of the above situation and an object thereof is to reduce insertion forces for a terminal fitting and adjusting the alignment of the terminal fitting.
The invention relates a connector with a housing with a base wall and through holes that penetrate the base wall in a thickness direction. Terminal fittings are insertable into the through holes. Each terminal fitting is long and narrow, and has at least one projection projecting out in a width direction. At least one press-in portion is located before the projection with respect to an inserting direction and is pressed into a space defined by the inner surface of the through hole. At least one inclination is formed on the inner surface of each through hole and is narrowed towards the front with respect to the inserting direction of the terminal fitting from one end surface of the base wall. The inclination is at a position corresponding to the projection for guiding the terminal fitting. At least one substantially straight portion is located before the inclination with respect to the inserting direction of the terminal fitting and extends in the inserting direction towards the other end surface of the base wall. The straight portion has at least one press-in area for the press-in portion. At least one restriction defines at least one step together with the substantially straight portion and extends from a taper end of the inclined portion to the step for tightly holding a front area of the projection with respect to the inserting direction while preventing loose movements of the projecting portion.
Front areas of the projections with respect to the inserting direction are held tightly by the restrictions of the through holes while having loose movements thereof prevented. Thus, the terminal fittings are positioned and aligned. Accordingly, the press-in portions do not require large press-in margins engageable with the press-in areas for alignment adjustment and inserting forces for the terminal fittings can be reduced.
Each restriction preferably tightly holds the front area of the corresponding projection with respect to the inserting direction in a pressed state. Thus, an external force is unlikely to shake the terminal fitting.
The substantially straight portion of each through hole preferably includes at least one recess that does not contact a plate surface of the facing terminal fitting. Thus, the inserting force for the terminal fitting is reduced even further, and abrasion related damage on the plate surface of the terminal fitting is prevented.
The terminal fitting preferably is aligned by the restriction.
A main portion of the terminal fitting preferably passes the straight portion of the through hole without contact during insertion of the terminal fitting.
The restriction preferably positions the projection of the terminal fitting substantially towards the center of the through hole, and preferably is formed by three mutually orthogonal surfaces for restraining the widthwise outer end of the projection in a thickness direction.
The projections preferably are substantially rectangular and are arranged at opposite lateral edges of the main portion. The projections preferably project farther from the lateral edges of the main portion than the press-in portions.
Two press-in portions preferably are spaced apart in the inserting direction.
A preceding press-in portion in the inserting direction preferably has a shorter projecting distance than a succeeding press-in portion.
A slanted edge of the preceding press-in portion preferably is connected to a tip via a curve or non-linear portion and a slanted edge of the succeeding press-in portion preferably is connected to a tip via an angle.
The press-in portion preferably contacts a lateral surface of the through hole in such a manner to bite therein.
These and other objects, features and advantages of the present invention will become more apparent upon reading of the following detailed description of preferred embodiments and accompanying drawings. It should be understood that even though embodiments are separately described, single features thereof may be combined to additional embodiments.
A connector according to a first embodiment of the invention is described with reference to
Each terminal fitting 60 is formed unitarily by press-working an electrically conductive (preferably metal) plate and has a long, narrow, flat rectangular tab. As shown in
The terminal fitting 60 is press fit into a base wall 21 of the housing 20 from the front and, after the insertion, the board connecting portion 62 projecting back from the rear of the housing 20 is bent at a substantially right angle towards the circuit board 90 to form an L-shaped bend 63. As shown in
Press-in portions 67 project laterally from the opposite sides of the main portion 64. The press-in portions 67 include a preceding press-in portion 65 disposed to be mounted first into the base wall 21 and a succeeding press-in portion 66 disposed to be mounted later into the base wall 21. The preceding press-in portion 65 preferably has a shorter projecting distance from the lateral edge of the main portion 64 than the succeeding press-in portion 66.
Each press-in portion 67 has a slanted edge 68 to gradually reduce the projecting distance toward the front with respect to the inserting direction ID. The slanted edge of the preceding press-in portion 65 is connected to a tip 69 via a smooth curved transition, whereas the slanted edge 68 of the succeeding press-in portion 66 is connected to a tip 69 via a non-smooth angled transition (i.e. the first derivative of the curve is non-continuous). The preceding press-in portions 65 are mounted smoothly into the base wall 21 because of their short projecting distance and the curved outer rear ends of the slanted edges 68. The succeeding press-in portions 66 are fixed strongly to the base wall 21 because of their longer projecting distance and the angled outer rear ends of the slanted edges 68.
The terminal fitting 60 also is formed with projections 71 projecting out in the width direction from the opposite lateral edges of the main portion 64 at a position behind the press-in portions 67 with respect to the inserting direction ID and towards the terminal connecting portion 61. The projections 71 are substantially rectangular and have a longer projecting distance from the lateral edges of the main portion 64 than the press-in portions 67. Thus, the terminal fitting 60 is wider at the projections 71. The projections 71, the press-in portions 67 and the main portion 64 have substantially the same thickness, and the projections 71 and the press-in portions 67 are transversely symmetrical with respect to the widthwise center of the main portion 64.
The housing 20 is made e.g. of synthetic resin and includes a wide rectangular tubular receptacle 22 with an open front end, as shown in
A base wall 21 extends vertically in the height direction at the back of the receptacle 22. Through holes 25 are formed in upper and lower levels of the base wall 21, and the terminal fittings 60 are pressed through the through holes 25 and held therein. As shown in
As shown in
The incline 26 is widened gradually towards the front surface of the base wall 21 and guides the terminal fitting 60 towards the center of the through hole 25. More specifically, as shown in
The straight portion 28 extends substantially straight in forward and backward directions to the rear surface of the base wall 21. More particularly, the straight portion 28 is defined by left and right facing surfaces 33 for receiving the press-in portions 67 of the terminal fitting 60 and upper and lower facing surfaces 34 for facing the opposite plate surfaces of the main portion 64 of the terminal fitting 60. The upper and lower facing surfaces 34 of the straight portion 28 are at the same sides as the slants 31 of the incline 26 and the front ends thereof are substantially continuous with the tapered end of the incline 26. The upper and lower facing surfaces 34 of the straight portions 28 are recessed and are substantially vertically symmetrically so as not contact the entire plate surfaces of the main portion 64. Additionally, the facing surfaces 34 are mountain-shaped and concave in cross section so that parts of the facing surfaces 34 corresponding to widthwise intermediate parts of the plate surfaces of the main portion 64 are most distant from these plate surfaces.
The left and right facing surfaces 33 of the straight portion 28 include substantially vertically arranged press-in areas for engaging the press-in portions 67. The press-in areas of the left and right facing surfaces 33 are wider than the main portion 64 of the terminal fitting 60, but narrower than the press-in portions 67. Thus, the press-in portions 67 contact and bite into the left and right facing surfaces 33 for pushing the left and right facing surfaces 33 outwardly in the width direction. A retaining force for the terminal fitting 60 is increased by the biting engagement of both the preceding press-in portions 65 and succeeding press-in portions 66.
The restrictions 27 position the rear part of the projection 71 of the terminal fitting 60 towards the center of the through hole 25, and is formed by three mutually orthogonal surfaces for restraining the widthwise outer end of the rear part of the projection 71 in the thickness direction. The restrictions 27 are arranged between the incline 26 and the left and right facing surfaces 33 of the straight portion 28 and are at positions substantially continuous with the opposite widthwise ends of the taper of the incline 26. More specifically, each restriction 27 is substantially continuous with the left or right facing surface 33 of the straight portion 28 and includes a step 35, a lateral end surface 36 and upper and lower main surfaces 37. The step 35 faces the front end of the projection 71. The lateral end surface 36 is between the vertical wall 32 of the incline 26 and the step 35 and faces the widthwise outer edge of the rear part of the projection 71. The upper and lower main surfaces 37 are between the slants 31 of the incline 26 and the step 35 to sandwich the rear part of the projection 71 in the thickness direction. The main surfaces 37 of the restriction 27 are flat and extend substantially straight in a horizontal direction from the rear edges of the slants 31 of the incline 26 to the step 35. The spacing between the main surfaces 37 substantially equals the thickness of the projection 71. A positioning space 38 is defined by the main surfaces 37, the lateral end surface 36 and the step 35 for holding the rear part of the projection 71 and to prevent any loose movements. As shown in
Upon mounting the terminal fitting 60 through the base wall 21, the board connecting portion 62 of the terminal fitting 60, prior to forming the bend 63, is oriented towards the front surface of the base wall 21 of the housing 20. The terminal fitting 60 then is inserted substantially horizontally in the inserting direction ID into the through hole 25 in this state. The incline 26 centers the board connecting portion 62 and corrects the inserting posture of the terminal fitting 60 during insertion of the terminal fitting 60 to ensure a smooth inserting operation. Further, the main portion 64 of the terminal fitting 60 passes the upper and lower facing surfaces 34 of the straight portion 28 of the through hole 25 without contact during insertion of the terminal fitting 60 so that no frictional resistance is produced.
The press-in portions 67 face the left and right facing surfaces 33 of the straight portion 28 when a final stage of the inserting operation is reached. Thus, the preceding press-in portions 65 and the succeeding press-in portions 66 are pressed successively into the press-in areas with the slanted edges 68 in the lead so as to bite in and engage the straight portion 28. Simultaneously, the projections 71 enter between the main surfaces 31 of the incline 26 and the rear parts of the projections 71 enter the positioning spaces 38 to be sandwiched in the thickness direction by the main surfaces 37 of the restrictions 27. The terminal fitting 60 is retained with the press-in portions 67 in an intermediate part of the straight portion 28 in forward and backward directions when the insertion is completed. The rear ends of the projections 71 face the steps 35 of the restrictions 27 to prevent the terminal fitting 60 from being pushed any further forward. Thus, the terminal fitting 60 is held centered and the restriction 27 prevents loose movements of the projections 71.
The terminal fittings 60 then are bent substantially perpendicularly down towards the circuit board 90 at intermediate positions to form the bends 63 so that the board connecting portions 62 extend down. The board connecting portions 62 then are inserted into the through holes of the circuit board 90 and are connected electrically with conductive paths of the circuit board 90 e.g. by soldering, welding, press-fitting, insulation displacement or the like. Further, the mating connector is fit into the receptacle 22 of the housing 20 to connect the terminal connecting portions 61 of the terminal fittings 60 with the respective mating terminal fittings.
As described above, front areas of the projections 71 with respect to the inserting direction ID are held by the restrictions 27 of the through holes 25 so as not to move loosely for positioning the terminal fittings 60. Thus, the terminal fittings 60 are aligned and centered, and it is not necessary to provide the press-in portions 67 with large press-in margins engageable with the press-in areas for alignment adjustment. Hence, the inserting forces for the terminal fittings 60 are low. Furthermore, the straight portions 28 of the through holes 25 include the recessed surfaces that do not contact the facing plate surfaces of the terminal fittings 60. Therefore, the insertion forces for the terminal fittings 60 are reduced further. Accordingly, abrasion and damage of the plate surfaces of the terminal fittings 60 is prevented and contact reliability is improved.
The straight portion 28 has mountain-shaped concave recessed surfaces 41 distanced from widthwise intermediate parts of the plate surfaces of the main portion 64 so as not to contact these widthwise intermediate parts and substantially flat surfaces 42 to be achieve surface contact with the opposite widthwise sides of the plate surfaces of the main portion 64. The recessed surfaces 41 and the flat surfaces 42 are vertically symmetrical.
According to the second embodiment, the widthwise intermediate part of the main portion 64 of the terminal fitting 60 does not contact the recessed surfaces 41 of the straight portion 28 during insertion of the terminal fitting 60 into the through hole 25. Thus, an inserting force for the terminal fitting 60 is low. In addition, after the insertion of the terminal fitting 60 into the through hole 25, the opposite widthwise sides of the main portion 64 of the terminal fitting 60 are adjacent to the flat surfaces 42 of the straight portion 28 and are sandwiched by the flat surfaces 42 of the straight portion 28. Thus, the terminal fitting 60 is prevented from shaking even upon the action of an external force.
The invention is not limited to the above described and illustrated embodiments. For example, the following embodiments are also embraced by the technical scope of the present invention as defined by the claims.
The front areas of the projections with respect to the inserting direction may be held tightly in a pressed state by the restrictions. Then, the terminal fitting is prevented from shaking in an external force acting direction. In this case, the spacing between the main surfaces of the restrictions may be made narrower toward the front with respect to the inserting direction of the terminal fitting to become smaller than the thickness of the projections.
The terminal fittings may be inserted into the through holes of the base wall from behind.
Three or more press-in portions may be arranged substantially side by side on each lateral edge of the main portion of the terminal fitting.
The straight portion of the through hole may be brought substantially into surface contact with the entire plate surfaces of the facing terminal fitting.
The terminal fittings may be formed straight without being bent in an L-shape or may have any other configuration as needed.
Number | Date | Country | Kind |
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2007-175765 | Jul 2007 | JP | national |