Abstract:
A method of making an electrical connector comprises assembling a frame mold ( 30 ) having front, rear, and bottom openings, a front mold ( 40 ) attached to the frame mold ( 30 ) from front and having a channel ( 43 ) for receiving the flexible section ( 21 ) and a portion of the intermediate section ( 23 ) of a terminal corresponding to the flexible section ( 21 ), a rear mold ( 50 ) attached to the frame mold ( 30 ) from rear and having a comb section ( 52 ) entering between the intermediate section ( 23 ) and the flexible section ( 21 ), and a bottom mold ( 60 ) attached to the frame mold ( 30 ) from below and having an upper support face ( 62 A) for supporting the intermediate section ( 21 ) of the terminal.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an electrical connector and a method of making the same. 
     2. Description of the Related Art 
     A connector comprising a rectangular housing having a receiving cavity for receiving a mating plug connector and a plurality of terminals extending obliquely in the receiving cavity for spring contact with terminals of the mating connector is well known. Japanese patent application Kokai No. 7-106010 discloses such a connector as shown in FIG.  9 . This connector  100  comprises a rectangular housing  101  having upper and lower openings and closing members  103  and  104  supporting a plurality of terminals  102 . 
     To make the connector  100 , the terminals  102  and the closing members  103  and  104  are formed integrally as a unit. Then, the terminals  102  are bent twice, and the closing members  103  and  104  are mounted in the housing  101 . More specifically, the substantially straight terminals  102 A and the closing members  103  and  104  are molded integrally in a line. Then, the terminal  102 A projecting from the closing member  104 A is bent in a direction A to form a contact section  105 . Then, the terminal  102 A is bent between the closing members  103  and  104  at right angles in a direction B. Then, it is mounted in the housing  101 . The contact sections  105  extend obliquely in the receiving cavity such that they make spring contact with the terminals of a mating connector that is inserted into the receiving cavity in a direction as shown by an arrow. 
     The above connector, however, has such disadvantages as separately forming the housing and the closing members, bending twice the terminals after molding, and mounting the closing members in the housing, making the manufacturing process complicated and pushing up the manufacturing cost. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the invention to provide a simple method of making a connector at a low cost and a connector made by such a method. 
     According to the invention there is provided an electrical connector comprising a substantially rectangular housing having a receiving cavity extending rearwardly from a front end of said housing for receiving a mating plug connector; a plurality of terminals arranged in said housing at regular intervals, each made by bending a metal pin and having an intermediate section with at least one retention portion retained in a wall of said housing that partially defines said receiving cavity, a flexible section diagonally extending from an end of said intermediate section for spring contact with a terminal of said plug connector, said flexible section and a corresponding portion of said intermediate section lying in a single plane, and a connection section extending from the other end of said intermediate section and projecting from said housing, wherein said terminal is molded integrally with said housing at said retention section. According to the invention, the housing is molded integrally with the terminal at the retention section. 
     It is preferred that the intermediate section is bent at right angles to form a bend across which there are provided said retention portions that are retained by upper and rear walls of said housing. The intermediate section may have a straight portion that is forward from said bend or said bend may be shifted laterally by a terminal arranging interval. 
     According to another aspect of the invention there is provided a method of making such an electrical connector, comprising the steps of assembling a frame mold having front, rear, and lower openings, a front mold attached to said frame mold from front and having on its top at least one channel for receiving said flexible section and a portion of said intermediate section opposed to said flexible section, a rear mold attached to said frame mold from rear and a comb section with at least one tooth entering between said intermediate and flexible sections of said terminal for contact them, and a bottom mold attached to said frame mold from below to form a metal mold; pouring a resin into said metal mold to mold said housing so as to retain said retention section of said terminal; and removing said respective molds to provide said electrical connector. 
     The method may further comprise the step of providing said comb section with a rear upper face that is equal to or higher than a lower face of said band and a front upper face that makes contact with a lower face of said intermediate section. The method may further comprise the steps of providing said comb section with an upper face of a rear portion that is equal to or higher than a lower face of said band and a front upper face that makes contact with a lower face of said intermediate section; shifting laterally said rear portion by a half of said terminal arranging interval; and moving laterally said metal mold by said half terminal arranging interval after said metal mold is inserted. 
     According to still another aspect of the invention there is provided a method of making such an electrical connector, comprising the steps of assembling (a) a frame mold having front, rear, and lower openings, (b) a front mold attached to said frame mold from front and having on its top at least one channel for receiving said flexible section and a portion of said intermediate section opposed to said flexible section, (c) a rear mold attached to said frame mold from rear and having at least one channel to support said intermediate section of said terminal, and (d) a bottom mold attached to said frame mold from below and having an upper face to support said intermediate section of said terminal to form a metal mold; pouring a resin into said metal mold to mold said housing so as to retain said retention section of said terminal; and removing said respective molds to provide said electrical connector. 
     The method may further comprises the step of providing said frame mold with a support mold having a retaining channel to retain said intermediate section of said terminal. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view, partially in section, of an electrical connector according to an embodiment of the invention; 
     FIG. 2 is an exploded, perspective view of various molds for making an integral molding of the electrical connector of FIG. 1; 
     FIG. 3 is a perspective sectional view of the molds assembled with terminals; 
     FIG. 4 is a perspective view, partially in section, of an electrical connector according to another embodiment of the invention; 
     FIG. 5 is an exploded, perspective view of various molds for integral molding of the electrical connector of FIG. 4; 
     FIG. 6 is a perspective, sectional view of the molds of FIG. 5 assembled with terminals; 
     FIG. 7 is an exploded, perspective view of various molds for integral molding of the electrical connector of FIG. 4 according to still another embodiment of the invention; 
     FIG. 8 is a perspective, sectional view of the molds assembled with terminals; and 
     FIG. 9 is a sectional view of a conventional electric connector. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Embodiments of the invention will now be described by way of example with respect to the accompanying drawings. 
     First Embodiment 
     In FIG. 1, a connector has a rectangular housing  10  that is molded from an insulative material such as a resin. A receiving cavity  11  extends rearwardly from the front end of the housing  10  to receive a mating plug connector. A cut-out  12  is provided in the bottom of the housing  10  to receive the lock releasing arm of the plug connector. The housing  10  has a rear wall with a portion thereof cut out, and upper and side walls. A plurality of terminals  20  are supported by the housing  10 . That is, the terminals  20  are molded together with the upper and rear walls  13  and  14  of the housing  10 . 
     The terminals  20  are made by stamping a plurality of pins extending from a carrier strip, bending the pins in a predetermined shape, molding integrally with the housing in a metal mold, and cutting off the carrier strip. Each terminal  20  has a flexible section  21  at an end, a connection section  22  at the other end, and an intermediate section  23  between them. The intermediate section  23  has an L-shaped bend  23 A in its middle and retention portions  23 B and  23 C that are supported by the upper and rear walls  13  and  14  of the housing  10 . The flexible section  21  extends obliquely rearwardly, making an acute angle with the retention portion  23 B in the upper wall  13 . The free end of the flexible section  21  makes spring contact with a terminal of the plug connector that is inserted into the receiving cavity  11 . 
     The L-shaped bend  23 A is offset laterally by one terminal arranging interval such that it is aligned with the intermediate section  23  of the adjacent terminal  23 . The connection section  22  has a horizontal end, which is placed on and soldered to the electrical circuit of a circuit board. The terminals  20  are molded integrally with the housing  10  and supported at the retention portions  23 B and  23 C. In FIG. 2, the molding is made by means of various molds. 
     A metal mold is composed of a frame mold  30 , a front mold  40 , a rear mold  50 , and a bottom mold  60 . These four molds are assembled to define a closed cavity for molding a housing. 
     The frame mold  30  has an upper plate  31  and opposite side plates  32  with the inner faces opposed to the outer faces of the upper and side walls  13  and  14  of the housing  10 . A support mold  33  with a plurality of support channels  33 A is provided on the inner face of the upper plate  31  to support the retention portions  23 B of terminals  20  at predetermined positions. 
     The front mold  40  has a plate section  41  to close the front face of the frame mold  30  and a block section  42  that enters into the frame mold  30 . A plurality of channels  43  are provided in the upper face of the block section  42  to receive the retention portions  23 A of intermediate sections  23  and the flexible section  21 . The depth of each channel  43  is set at such a value that the channel  43  can receive both the retention portion  23 A and the flexible section  21 , with the flexible section  21  flexed toward the retention portion  23 B. The upper face of each ridge  44  is lowered at a shoulder  44 A so that the lower face of the retention portion  23 B is slightly higher than the lowered upper face of the ridge  44 . Consequently, the retention portion  23 B of each terminal  20  is supported firmly by the housing on its upper face and part of the side faces. 
     The rear mold  50  has a plate section  51  to cover the rear face of the frame mold  30 , a comb section  52  extending forwardly from the plate section  51 , and a support section  53  provided on the lower part of the plate section  51 . Each tooth of the comb section  52  has a width equal to a gap between the terminals and a lower face  52 A tapered toward the front end thereof. It is inserted into a space between the intermediate section  23  and the flexible section  21 . The support section  53  has a plurality of channels  53 A to support the retention portions  23 C above the connection sections  22 . 
     The bottom mold  61  has a plate section  61  to close the bottom face of the frame mold  30  and a support wall  62  erected on the plate section  61 . When the support wall  62  is inserted into the frame mold  30 , the upper face  62 A abuts on the horizontal portion of the bends  23  of terminals  20  for support. 
     How to make the connector will be described below. 
     (1) First of all, a metal sheet is stamped to provide a row of pins extending from an edge of a carrier strip. 
     (2) Then, the pins are bent to provide a set of terminals  20  (connected to the carrier strip C) as shown in FIG.  1 . 
     (3) Then, the terminal set is supported by the four molds; i.e., the frame mold  30 , the front mold  40 , the rear mold  50 , and bottom mold  60  (FIG.  3 ). Then, a resin is put into the cavity defined by these molds to provide a molded connector in which the terminals are supported by the housing at the retention portions  23 B and  23 C as shown in FIG.  1 . 
     (4) Finally, all the molds  30 ,  40 ,  50 , and  60  are removed and the carrier strip C is cut off at the ends of the connection sections  22 . 
     Second Embodiment 
     In FIG. 4, this connector is the same as the FIG. 1 embodiment except that the flexible section  21 , the connection section  22 , and the intermediate section  23  lie in a single flat plane. In this figure, the wall or cover section of each mold is omitted. 
     The respective molds for making this connector are changed from the FIG. 2 molds to those such as shown in FIG.  5 . 
     (a) The rear mold  50  does not have any comb-like section but a support section  54  that is the same as support section  53 . Consequently, the vertical portions of terminals  20  below the L-shaped bends  23  are supported in two channels  53 A and  54 A of the support sections  53  and  54 . 
     (b) The upper faces of respective ridges  44  on the front mold  40  lie in a single flat plane. The retention portions  23 B of the terminals project slightly from the flat plane. 
     (c) A plurality of channels  62 B are provided in the upper face of the support wall  62  to support the intermediate sections  23  of terminals. 
     Similarly to molding of the FIG. 1 connector, these molds are used to make integral molding of the housing and terminals (FIG.  6 ). In this embodiment, the respective molds surround the flexible sections and the corresponding intermediate sections. 
     Third Embodiment 
     According to the third embodiment, the FIG. 4 connector is made by a metal mold that is different from the FIG. 5 mold. 
     In FIG. 7, the rear mold  50  is different from that of FIG. 5 and, according to this difference, the front and bottom molds  40  and  60  are also different. The rear mold  50  is similar to that of FIG. 2 except that the comb section  52  is offset by a half of the terminal arranging interval at the base position  52 B. After it is inserted into the metal mold, the comb section  52  is moved by the offset distance in the arranging direction after the base position  52 B passed the vertical retention portion  23 C so that the front portions of the comb section  52  from the base position  52 B are placed under the retention portions  23 B at positions similar to those of FIG.  1 . 
     The support wall  62  has teeth  62 B and grooves  62 C between the teeth  61 B. The grooves  62 C are tilted to receive the tilted sections of the comb section  52 . The front mold  40  is different from that of FIG. 2 in that the ridge  44  forming the end groove  43  has a protruded section  44 B. The protruded section  44 B has a sloped face  44 C which cooperates with the uttermost right-hand tooth  62 B to form a groove that is similar to the groove  62 C. These molds are assembled in the same manner as in the first embodiment to make molding as shown in FIG.  8 . 
     As has been described above, according to the invention, the terminals made by bending are molded integrally with the housing at once to provide a connector so that it is very easy to make at a low cost. Since the terminals are supported directly by the housing, the terminal retention becomes strong. The precision of molds is so high that the positions of terminals are very precise.