Patent Document

BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a card connector, and more particularly to a card connector in which a card insertion space is formed by a body made of an integral molded product of a synthetic resin, and a sheet metal frame attached to the body. 
   In some of the card connectors of this kind, a body comprises a head portion having multipolar contacts, and a pair of right and left arms which are extended from the head portion, so that the right and left arms guide insertion of a card. In such a card connector, when the right and left arms are deformed to be displaced outwardly or inwardly from their original design positions, the operability of card insertion is impaired, or a card cannot be sometimes inserted. In the case where both the right and left arms are deformed to be inwardly displaced, particularly, the slot width (the lateral dimension of a card insertion slot) is excessively small even when one of the arms is displaced at a small degree, thereby impairing the operability of card insertion. In an extreme case, a card cannot be inserted into the connector. In the case where a thin body which has a small width and a thickness of only about several mm (2 to 3 mm) is requested to be produced by integral molding of a synthetic resin, the above situation is particularly remarkable because, for example, increases of the thickness and width of the arms are limited. 
   The specification of Japanese Patent No. 2,533,829 (FIGS. 4, 9, and 14) (hereinafter, referred to as “Patent literature 1”) discloses a memory card connector. In the memory card connector, a reinforcement plate made of a sheet metal which cooperates with such a body to form a card insertion space is stretched between a pair of side guide arms (corresponding to the above-mentioned arms) of a connector housing made of a integral molded product of a synthetic resin. Retention tabs which are formed by bending right and left side edges of the reinforcement plate are inserted into slots (channels) which are formed in longitudinal middle portions of the side guide arms, respectively, thereby reinforcing the side guide arms. Patent literature 1 discloses also a structure in which a tang that is directly opposed to a grounding printed circuit for removing electrostatic charges from a main board is punched out in a tip end portion of the reinforcement plate, and a rectangular piece formed by a residual punching metal is inserted into a channel formed in the vicinity of the tip end of the corresponding side guide arm. In the memory card connector of Patent literature 1, recessed edges formed in a lower plate portion which is continuously integrated with the pair of side guide arms and a head portion have a rectangular shape. 
   The specification of Japanese Utility Model Registration No. 3,086,612 (hereinafter, referred to as “Patent literature 2”) discloses an electronic card connector in which a reinforcement plate is extended between longitudinal middle portions of right and left side arms, the right and left side arms and the reinforcement plate are integrally molded by a synthetic resin, and the profile of the tip end edge of the reinforcement plate is formed into a recessed shape. 
   In the connector disclosed in Patent literature 1, the right and left retention tabs of the reinforcement plate are simply inserted into the slots configured by channels formed in the respective longitudinal middle portions of the pair of side guide arms. Although each of the side guide arms can be prevented from being deformed in a range between the inserted portion and the basal portion of the side guide arm, therefore, a portion which is closer to the tip end than the inserted portion serving as a portion for forming a card insertion slot cannot be effectively prevented from being deformed. In the case where the thickness and width of the side guide arms are reduced so as to thin and narrow the connector housing, the card insertion slot is excessively narrowed by deformations, particularly, inward deformations of the side guide arms, and the possibility that the operability of card insertion is impaired is increased. In order to form the slots into which the retention tabs of the reinforcement plate are to be inserted, the reduction of the widths of the side guide arms is limited. In the case where the connector housing is requested to be further narrowed and thinned, therefore, even the slots into which the retention tabs are to be inserted cannot be formed in the side guide arms. Consequently, the technique disclosed in Patent literature 1 in which the side guide arms are reinforced by inserting the retention tabs of the reinforcement plate into the slots formed in the side guide arms has a difficulty in promoting narrowing and thinning of the connector housing. Patent literature 1 discloses also the structure in which the rectangular piece in the tip end portion of the reinforcement plate is inserted into the channel formed in the vicinity of the tip end of the corresponding side guide arm. Although the structure can prevent each of the side guide arms from being deformed in a range between a vicinity of the tip end of the side guide arm and the inserted portion, the foremost end portion of the side guide arm cannot be prevented from being deformed. Since the channel for inserting the rectangular piece must be formed in the side guide arm, moreover, the above-discussed difficulty in promoting narrowing and thinning of the connector housing cannot be solved. 
   By contrast, Patent literature 2 simply discloses the technique in which, in the case where the reinforcement plate and the right and left side arms are integrally molded by a synthetic resin, even when the reinforcement plate is warped and the lateral middle portion of the card insertion slot is narrowed, a card inserted into the card insertion slot gradually pushes the lateral middle portion of the reinforcement plate, and the card is enabled to be inserted. The technique cannot solve the problem in that the right and left side arms are inwardly deformed to excessively narrow the card insertion slot. 
   As described above, Patent literature 1 discloses only the technique in which the right and left side guide arms are reinforced by using the reinforcement plate, and the reinforcement plate disclosed in Patent literature 2 simply provides the technique of reinforcing the right and left side arms. These literatures fail to provide a technique in which right and left arms are prevented from being deformed in an ensured manner based on the design, thereby improving the operability of card insertion and enabling a card connector to be easily narrowed and thinned. 
   The invention was developed in view of the above-mentioned circumstances. It has been found that a phenomenon in which right and left arms are deformed to be inwardly displaced from their original design positions because of a problem of the molding technique does not occur in the case where a body is provided with a lower plate portion which is extended between the right and left arms, a recessed portion that is recessed toward such a head portion is formed in the lower plate portion, and right and left recessed edges of the recessed portion are formed into an arcuate shape to enhance the breakage resistance. It is an object of the invention to provide a card connector in which a structure for preventing a pair of right and left arms from being deformed without forming a slot in the arms as disclosed in Patent literature 1 and properly positioning the arms to their original design positions is produced, so that, even when the card connector is further narrowed and thinned, the lateral width of a card insertion slot which is formed between the foremost ends of the right and left arms is adequately defined and the operability of card insertion is maintained to a satisfactory level. 
   It is another object of the invention to provide a card connector in which right and left arms are prevented from being inwardly deflected, whereby card insertion can be prevented from being impaired in operability or disabled. 
   It is a further object of the invention to provide a card connector in which a sheet metal frame that cooperates with a body having arms to form a card insertion space is used so as to eliminate causes of impairing the operability of card insertion by deforming the arms, without increasing the number of parts. 
   It is a still further object of the invention to provide a card connector of excellent durability in which, even when the card connector is narrowed and thinned by reducing the thickness and width of each of right and left arms, the arms can be provided with sufficient strength without increasing the number of parts. 
   SUMMARY OF THE INVENTION 
   In the card connector of the invention, a sheet metal frame cooperates with a body to form a card insertion space, the body being made of an integral molded product of a synthetic resin in which a pair of arms are extended from a head portion having multipolar contacts, the frame being placed between the arms. In the card connector, terminals of a card inserted into the card insertion space are respectively in contact with the multipolar contacts of the head portion, thereby electrically connecting them together. 
   In the invention, the frame comprises arm supporting means for blocking inward deflections of foremost end portions of the arms. According to the configuration, the arm supporting means of the frame blocks inward deflections of the foremost end portions of the arms, and hence each of the arms is prevented from being deformed in the whole length from the basal portion of the arm to the foremost end. Therefore, a phenomenon in which the card insertion slot and the card insertion space that are formed between the foremost end portions of the right and left arms are excessively narrowed to impair the operability of card insertion or disable a card to be inserted does not occur. Also reduction of the operability of card insertion due to deformations of the arms can be surely prevented from occurring. 
   In the invention, preferably, the arm supporting means is configured by a receiving piece which is to butt against an inward engagement face that is provided in a foremost end portion of one of the arms, and the receiving piece is formed by bending the frame. According to the configuration, the receiving piece of the frame butts against the inward engagement face in the foremost end portion of the arm, whereby inward deformation of the arm is blocked. Therefore, slots (channels), which are disclosed in Patent literature 1 are not required to be formed in the arm. As a result, the thickness and width of the arm can be easily reduced, so that the body can be further narrowed and thinned. 
   In the invention, preferably, the arm supporting means is configured by a pair of receiving pieces which are to butt against inward engagement faces that are provided in foremost end portions of the pair of arms, respectively, and the receiving pieces are formed by bending the frame. According to the configuration, inward deformations of the pair of right and left arms are blocked. Therefore, narrowing and thinning of the body having the structure in which the pair of right and left arms are extended from the head portion can be easily promoted. 
   In the invention, preferably, the body is provided with a lower plate portion which is continuously integrated with the head portion and the pair of arms, the card insertion space being formed between the lower plate portion and the frame, a recessed portion that is recessed toward the head portion is formed in the lower plate portion and between the pair of arms, and right and left recessed edges of the recessed portion are formed into an arcuate shape. According to the configuration, insertion of a card is guided by the frame and the lower plate portion of the body, so that the operability of card insertion is improved. Even when the lower plate portion having the recessed portion is thinned so as to further reduce the thickness of the card connector, recessed corners of the lower plate portion are hardly broken because the recessed edges of the recessed portion are formed into an arcuate shape. As compared with the case where the recessed edges of the recessed portion are formed into a perpendicular shape, moreover, the lower plate portion exerts more satisfactorily the function of preventing the basal portions of the right and left arms from being deformed. 
   In the invention, preferably, the pair of receiving pieces are extended in a thickness direction of a card which is to be inserted into the card insertion space, and a lateral width of an insertion slot of the card insertion space is defined by a distance between opposing inward faces of the receiving pieces. According to the configuration, the lateral width of the insertion slot of the card insertion space can be accurately defined, and hence the operability of card insertion is stabilized. 
   In the invention, preferably, plate-like pieces which overlap outward faces of the pair of arms to reinforce the arms respectively are formed by bending the frame. Preferably, the frame has a face plate portion which is extended from the head portion of the body to the foremost end portions of the arms, and positions of the foremost end portions of the arms where the engagement faces are formed are clamped between the plate-like pieces and the receiving pieces, respectively. According to the configuration, a structure is produced in which the arms are reinforced by the plate-like pieces of the frame and each of the arms is laterally clamped between the corresponding receiving piece and plate-like piece of the frame. Even when the card connector is narrowed and thinned by reducing the thickness and width of the arms, therefore, the arms are surely provided with sufficient strength. 
   As described above, according to the invention, although slots which are disclosed in Patent literature 1 are not formed in the arms, the arms can be prevented from being deformed, and properly positioned to their original design positions. Even when the card connector is further narrowed and thinned by reducing the thickness and width of the arms, therefore, the lateral width of the card insertion slot which is formed between the foremost ends of the right and left arms is adequately defined and the operability of card insertion is satisfactorily maintained. Particularly, the invention can achieve the remarkable effect that the sheet metal frame that cooperates with the body having the arms to form the card insertion space is used so as to eliminate causes of impairing the operability of card insertion by deforming the arms, without increasing the number of parts. Moreover, even when the card connector is narrowed and thinned, the arms of the body can be provided with sufficient strength without increasing the number of parts, and hence a card connector in which narrowing and thinning are promoted can be provided with excellent durability. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an external perspective view of a card connector which is an embodiment of the invention; 
       FIG. 2  is an external perspective view of a body; 
       FIG. 3  is an enlarged perspective view showing a foremost end portion of a left arm of the body; 
       FIG. 4  is an enlarged perspective view showing a foremost end portion of a right arm of the body; and 
       FIG. 5  is an enlarged section view of main portions, partially omitted. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1  is an external perspective view of a card connector which is an embodiment of the invention,  FIG. 2  is an external perspective view of a body  1 ,  FIGS. 3 and 4  are enlarged perspective views showing different portions of the body  1 , and  FIG. 5  is an enlarged section view of main portions, partially omitted. 
   As shown in  FIG. 2 , the body  1  is made of an integral molded product of a synthetic resin, and a pair of arms  3   a ,  3   b  are extended from left and right ends of a laterally elongated head portion  2 , respectively. A lower plate portion  4  is continuously integrated with the head portion  2  and the pair of arms  3   a ,  3   b . A contact row  21  configured by a predetermined number contacts which are laterally arranged is incorporated into the head portion  2 . The lower plate portion  4  has a recessed portion  41  which is between the pair of arms  3   a ,  3   b , and which is recessed toward the head portion  2 . In the recessed portion  41 , right and left recessed edges  42   a ,  42   b  are formed into an arcuate shape. In the case where the recessed portion  41  is formed in the lower plate portion  4  in this way, even when the lower plate portion  4  is molded so as to have a reduced thickness, stress concentration hardly occurs in the recessed edges  42   a ,  42   b  because of the arcuate shapes of the recessed edges  42   a ,  42   b , so that the lower plate portion  4  is hardly broken in the recessed edges  42   a ,  42   b . The formation of the recessed portion  41  in the lower plate portion  4  is useful for suppressing the amount of a resin material for molding the body  1 , and produces advantages such as that, when the body  1  is mounted on a circuit board or a chassis which is not shown, the mounting state can be easily stabilized. To one of the left and right arms  3   a ,  3   b , or to the left arm  3   a , attached are a lock spring  12  for locking a card (not shown) to an adequate set position, a spring member  13  for ejecting a card, and a cam mechanism  14  which performs a certain kind of operation. By contrast, components such as a card detection switch  15  for detecting insertion of a card are attached to the right arm  3   b.    
   As shown in  FIG. 1  or  5 , a sheet metal frame  5  is attached to the body  1 . The frame  5  has a face plate portion  51  which is extended from the head portion  2  of the body  1  to the foremost end portions  3   a′ ,  3   b ′ of the arms  3   a ,  3   b . Plate-like pieces  52   a ,  52   b  which are longitudinally extended, and which are formed by bending the left and right ends of the face plate portion  51  overlap outward faces  31   a ,  31   b  of the left and right arms  3   a ,  3   b , respectively. The left and right plate-like pieces  52   a ,  52   b  exert functions of blocking outward deformations of the left and right arms  3   a ,  3   b , and reinforcing the arms  3   a ,  3   b . The body  1  and the frame  5  are coupled to each other so as not to rattle longitudinally and vertically, by engaging engagement holes  53  and engagement hooks  54  which are formed in plural front and rear positions of the plate-like pieces  52   a ,  52   b  of the frame  5 , with engagement projections  32  and stepped faces (not shown in the figures) which are formed in corresponding positions of the arms  3   a ,  3   b.    
   In a tip end portion of the frame  5 , hook-like receiving pieces  55   a ,  55   b  are bendingly formed by vertically downwardly die-cutting and raising two or left and right places of the face plate portion  51 , respectively. By contrast, as shown in  FIG. 3  or  4 , an inward engagement face  33   a  is formed in the foremost end portion  3   a ′ of the left arm  3   a , and an inward engagement face  33   b  is similarly formed in the foremost end portion  3   b ′ of the right arm  3   b . As shown in  FIG. 5 , the receiving pieces  55   a ,  55   b  of the frame  5  overlap the engagement faces  33   a ,  33   b  in a butting condition, respectively, to block inward displacements of the foremost end portions  3   a ′,  3   b ′ the left and right arms  3   a ,  3   b . Since the foremost end portions  3   a ′,  3   b ′ of the left and right arms  3   a ,  3   b  are prevented by the left and right receiving pieces  55   a ,  55   b  of the frame  5  from being inwardly displaced in this way, the whole lengths of the arms  3   a ,  3   b  are not inwardly deflects. In the embodiment, an outward engagement piece  56  is extended from the left receiving piece  55   a , and the engagement piece  56  is inserted into a channel  36  formed in the arm  3   a . The configuration has an advantage that the tip end of the frame  5  is coupled with the foremost end portion of the arm  3   a  of the body  1  and hence the coupling force between the body  1  and the frame  5  is enhanced. 
   In the embodiment, as shown in  FIG. 1  or  2 , each of the left and right plate-like pieces  52   a ,  52   b  of the frame  5  is extended to reach the engagement face forming position a, b (see  FIG. 3  or  4 ) of the foremost end portion of the corresponding one of the left and right arms  3   a ,  3   b , and the engagement face forming position a, b is clamped between the plate-like piece  52   a ,  52   b  and the receiving piece  55   a ,  55   b . In the case where the body  1  is produced by integral molding of a synthetic resin, even when the arms  3   a ,  3   b  of the molded body  1  are inwardly deflected for a technical reason in molding, therefore, the deflections of the arms  3   a ,  3   b  are adequately corrected by the clamping function exerted by the plate-like pieces  52   a ,  52   b  and the receiving pieces  55   a ,  55   b.    
   In the embodiment, the pair of receiving pieces  55   a ,  55   b  are extended in the thickness direction T of a card C (see  FIG. 1 ) which is to be inserted into a card insertion space formed by a space between the lower plate portion  4  of the body  1  and the face plate portion  51  of the frame  5 , and, as shown in  FIG. 5 , the lateral width W of a insertion slot of the card insertion space is defined by the distance between opposing inward faces of the receiving pieces  55   a ,  55   b . In the left and right arms  3   a ,  3   b , guide faces  35   a ,  35   b  are formed in extended planes of the inward faces of the left and right receiving pieces  55   a ,  55   b  (see  FIG. 1 ,  3 , or  4 ), respectively. 
   In the thus configured card connector, when the card C is inserted as indicated by the arrow A in  FIG. 1 , the lateral position of the card C is restricted by the left and right receiving pieces  55   a ,  55   b  and the guide faces  35   a ,  35   b , and the lateral width W of the insertion slot is maintained to the adequate dimension by the left and right receiving pieces  55   a ,  55   b . Therefore, the card C can be inserted smoothly and in a proper posture. Even when a prying force is applied to the card C during a process of manually inserting the card C, the prying force is received not only by the left and right arms  3   a ,  3   b , but also by the receiving pieces  55   a ,  55   b  and the plate-like pieces  52   a ,  52   b . Even when the arms  3   a ,  3   b  are so thin and narrow that the arms  3   a ,  3   b  fail to have a considerably large strength, therefore, there arises no possibility that the arms  3   a ,  3   b  are deformed or broken. As a result, even when the card connector is narrowed and thinned by reducing the thickness and width of each of the arms  3   a ,  3   b , the arms can be provided with sufficient strength.

Technology Category: 3