Board connecting connector and method for producing the same

A plug connector is provided with a housing into which the receptacle connector is to be inserted, and a plurality of pin terminals arranged in the housing. The receptacle connector is provided with a plurality of contacts having contact members to be brought into contact with the pin terminals, and a housing holding the contacts. In the plug connector, a plurality of vertical shield plates are provided between the pin terminals. In the receptacle connector, a plurality of horizontal shield plates are provided so as to intersect the vertical shield plates in a cross-like manner. Provided in the housing and the horizontal shield plates of the receptacle connector are slits for allowing insertion of the vertical shield plates. The housing of the plug connector is provided with terminal unit mounting passage for the unit terminals and vertical shield mounting passage for the vertical shield plates.

BACKGROUND OF THE INVENTION

The present invention relates to a backplane type connector for connecting circuit boards electrically to each other, and to a method of producing the same.

Board-to-board connectors are widely used for connecting circuit boards to each other in order to increase the density of circuits or realizing a spatial arrangement of multiple circuit boards. These type of connectors generally include receptacle and plug connectors. The receptacle connector is mounted on a vertical circuit board, while the plug connector is mounted on a daughterboard. It is common for the surfaces of the daughterboards to be perpendicular to the surface of the backplane board, when the two connectors being mated together. Examples of the backplane type connector are disclosed in Japanese Patent Publication A-H06-013133 and U.S. Pat. No. 4,655,518

Recently, these backplane connectors have included multiple pin connectors in which the number of terminal pins ranges from several tens to several hundreds, and these are used in high-speed applications. These backplane connectors have the following problems.

The first problem relates to the electromagnetic shielding of the signal terminals. In some backplane connectors, the shield is only partly taken into account. For example, there exists a plug connector in which signal terminal pins are arranged in a plurality of rows and in a plurality of columns in the connector housing. Shield plates extend in the vertical direction at intervals in the housing width direction. As a result, cross-talk is generated between signal terminals between which there exists no shield plate.

The second problem is related to the manufacturability and production cost of the receptacle connector. There exists a receptacle connector equipped with a large number of contacts in which there are arranged in a lattice-like fashion, for example, 25 pins in the housing width direction and five pins in the housing thickness direction. In this receptacle connector, the large number of contacts are forced into attachment holes of the housing and attached thereto. In the process, the contacts and shield plates are alternately forced into the holes. Since the shield plates are forced in vertically, only five vertical rows of contacts can be forced in at one time. As a result, it is necessary to perform the contact-forcing-in process and the shield-plate-forcing-in process for every 25 times each, that is, for every 50 times in total, resulting in poor manufacturability and high production cost. Needless to say, the problem of the shield described above, is not solved in this case, either.

Japanese Patent Publication A-H07-114952 discloses a multi-polar electric connector in which shielding is possible not only between signal terminals of different rows but also between adjacent signal terminals of the same row. This technique is suitable for a relatively simple connector with a small number of poles. However, as the number of poles increases, the number of parts including shield plates, increases steeply, resulting in an increase in production cost due to the increase in assembly man-hour and the complication of the assembly operation. Further, the larger the number of poles is, the more complicated and the more delicate the housing becomes, which leads to a problem related to formability and a problem related to the manufacturability of the mold.

SUMMARY OF THE INVENTION

It is an object of the present invention to solve the problem of the shield in a connector to thereby prevent the generation of cross-talk or the like and, further, to achieve, by forming the connector components as units, a reduction in assembly man-hour and an improvement in formability and manufacturability to thereby achieve an overall reduction in production cost.

To achieve the above object, the present invention adopts the following means.

A backplane type connector for connecting boards electrically to each other comprises a receptacle connector mounted on one board and a plug connector mounted on the other board. The plug connector includes an opening into which the receptacle connector is inserted, and a plurality of pin terminals arranged in a lattice-like fashion in a plurality of vertical and horizontal rows with respect to the housing, and a plurality of vertical shield plates arranged parallel to each other between the pin terminals. The receptacle connector includes a plurality of contacts provided with contact members to be brought into electrical contact with the pin terminals, a plurality of horizontal shield plates arranged parallel to each other so as to intersect the vertical shield plates in a cross-like fashion, and a housing holding the contacts and the horizontal shield plates. Provided in the housing and the horizontal shield plates of the receptacle connector are slits for allowing insertion of the vertical shield plates.

In accordance with the present invention, in the receptacle connector, a plurality of horizontal shield plates arranged in parallel are provided so as to intersect the vertical shield plates of the plug connector in a cross-like fashion, so that there exist shield plates in all the spaces between the signal terminals, whereby the problem of the shield in the connector is solved to thereby preventing the generation of cross-talk or the like.

Further, in accordance with the present invention, the plurality of pin terminals of the plug connector are formed as unit terminals in which the vertical rows of pin terminals between the vertical shield plates are integrated by resin mold portions, and the housing of the plug connector is provided with terminal unit mounting passages for the unit terminals and vertical shield mounting passages for the vertical shield plates. In this way, the plug connector is also in a unit form, whereby it is possible to achieve a reduction in assembly man-hour and an improvement in formability and manufacturability, thereby reducing overall production cost.

It is desirable that the housing of the plug connector of the present invention be provided with a top plate, a bottom plate, and a back plate so as to exhibit a C-shaped sectional configuration, and that the terminal unit mounting passages be provided in the back plate, the vertical shield mounting passages being provided at least in the back plate, and additionally in the top plate and/or the bottom plate. This enables the vertical shield plates to be supported in a stable manner by three portions (three-point support): the back plate, the top plate, and the bottom plate forming the vertical shield mounting passages.

Here, it is desirable that the terminal unit mounting passages be formed by a plurality of terminal insertion holes provided in the back plate, and that the vertical shield mounting passages be formed by a plurality of slits provided in the back plate and guide grooves provided in the top plate and the bottom plate and adapted to guide the upper edge portions and the lower edge portions of the vertical shield plates. The plurality of insertion holes retain the pin terminals at fixed positions. The slits provided in the back plate serve to enable the vertical shield plates to be inserted into the housing, and the guide grooves serve to retain the upper edge portions and lower edge portions of the vertical plates at fixed positions, whereby the mounting and positioning of the vertical shield plates with respect to the housing are facilitated.

It is desirable that at least one ground tail connected to the other board be provided in the vertical shield plates of the plug connector at an arbitrary position. When a ground tail is thus provided in the vertical shield plates, it is possible to provide the ground tail simultaneously with the vertical shield plates when processing the latter, so that not only is it possible to achieve a satisfactory manufacturability, but also the number of ground tales can be easily changed as needed. Further, the ground tail can be easily provided at an arbitrary position in the vertical shield plates in correspondence with the arrangement position, place, etc. of the other board to which it is connected.

In accordance with the present invention, the receptacle housing, the contacts, etc. are formed as units, and the horizontal shield plates are integrated with the housing units, whereby it is possible to achieve a reduction in assembly man-hour and an improvement in moldability (formability) and manufacturability, thereby achieving a reduction in overall production cost.

Further, by stacking a plurality of housing units in a plurality of stages in the housing thickness direction and connecting them to each other, it is possible to reduce the number of housing units.

In the present invention, when the pin terminals and the contact members of the contacts are in a state in which they are electrically connected to each other, it is desirable that the periphery of each connection portion be surrounded by vertical shield plates and horizontal shield plates. By thus surrounding the peripheries of the connection portions where the pin terminals are connected to the contact members by the vertical shield plates and the horizontal shield plates, it is possible to prevent cross-talk more reliably.

The horizontal shield plates of the present invention may be integrated with the respective housing units by insert molding. In this case, it is possible to integrate the horizontal shield plates with the housing units when forming the latter, so that it is possible to achieve an improvement in both manufacturability and assembly property.

Further, it is desirable that at least one ground tail connected to the other board be provided in the horizontal shields at an arbitrary position. When a ground tail is thus provided also in the horizontal shield plates, it is possible to provide the ground tail simultaneously with the horizontal shield plates when processing the latter, so that not only is the manufacturability satisfactory, but also it is possible to change the number of ground tails as needed.

It is also desirable to adopt a construction in which, in each housing unit, attachment holes for the contact modules are arranged at intervals in the housing unit width direction, the slits being provided between the attachment holes. By thus providing the slits between the attachment holes, it is possible to allow the vertical shield plates on the plug connector side to enter the portions between the attachment holes.

It is also desirable that engagement portions adapted to engage with each other to join the housing units to each other be provided on the joint surfaces of the housing units. Due to the engagement portions, the housing units can be easily and detachably joined together without being glued to each other.

It is also desirable to provide a plurality of contact modules respectively connected to the rear ends of the housing units, each contact module being provided with a group of contacts to be forced into the respective attachment holes and a group of tails serving as leading conductors connecting the contacts to the board, the portion of each contact module other than the group of contacts and the group of tails being resin-molded. In this construction, the housing units can be connected to the contact modules solely by fitting the group of contacts into the respective attachment holes, whereby it is also possible to simultaneously force in a plurality of groups of contacts corresponding to horizontal rows for connection.

On the other hand, the method of the invention is a method for producing a receptacle connector comprising a plurality of first and second housing units which are stacked together in a plurality of stages and can be connected to each other, a lower stage housing unit provided in the lowermost stage, an upper stage housing unit provided in the uppermost stage, horizontal shield plates respectively provided in the housing units, and contact modules respectively connected to the rear ends of the housing units. The method comprises the following first to fourth steps.

A first step for integrating the horizontal shield plates respectively with the housing units beforehand.

A second step for connecting vertically adjacent housing units to each other while alternately stacking in a plurality of stages the first and second housing units provided with the horizontal shield plates.

A third step for connecting the lower stage housing unit to the first housing unit and connecting the upper stage housing unit to the second housing unit.

A fourth step for forcing the contact modules into the rear end portions of the housing units for connection.

In the production method of the present invention, a plurality of first and second housing units that can be stacked together in a plurality of stages and connected to each other, a lower stage housing unit provided in the lowermost stage, an upper stage housing provided in the uppermost stage, horizontal shield plates respectively provided on the housing units, and contact modules connected to the respective rear ends of the housing units, are assembled. By integrating the horizontal shield plates respectively with the housing units beforehand, it is possible to simplify the construction of the connector as a whole and facilitate the assembly thereof.

In actually assembling the connector, vertically adjacent housing units are joined to each other while alternately stacking the first and second housing units provided with the horizontal shield plates in a plurality of stages, whereby it is possible to simultaneously force in all the contacts arranged in horizontal rows. Thus, the contact forcing-in process is in correspondence with the number of stages in which the housing units are stacked together. For example, when the number of stages is five, it is only necessary to perform the contact forcing-in step five times. In this way, the number of times that the contact forcing-in step is performed is reduced, thereby achieving an improvement in manufacturability and a reduction in production cost.

It is desirable that, in the first step, the horizontal shield plates be respectively integrated with the housing units by insert molding. When this method is adopted, the horizontal shield plates can be integrated with the housing units when forming the latter, so that it is possible to achieve an improvement in both manufacturability and assembly property.

Further, it is desirable to provide on the joint surfaces of the housing engagement portions adapted to engage with each other to join the housing units to each other. This is very convenient in performing the operation of assembling the housing units in turns by successively stacking them together.

In the process, it is desirable to cause the engagement portions to engage with each other by causing the second housing units to make a relative movement from the rear to the front side of the first housing units. This helps to further improve the assembly operation.

Further, it is desirable to provide short bars for electrically connecting the horizontal shield plates after the receptacle connector has been assembled by the first through fourth steps. This makes it possible to short-circuit the horizontal shield plates, thereby making it possible to obtain a more stable shield property.

These and other objects, features and advantages of the present invention will be clearly understood through a consideration of the following detailed description.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In this embodiment, the present invention is applied to a backplane type connector for electrically connecting boards, which are connected in a so-called right-angle connection, in which the surfaces of the boards cross each other at right angles. This backplane type connector comprises, as shown inFIG. 3, a receptacle connector10mounted on the surface of vertical board K1and a plug connector20mounted on the surface of a daughter board K2.

As shown inFIG. 2, the plug connector20is provided with a housing22having an opening21into which the receptacle connector10is to be inserted, and a plurality of pin terminals23arranged in a lattice-like fashion with respect to the housing22. The housing22is of a C-shaped configuration in a side view and has a top plate24, a bottom plate25, and a back plate26. The housing22is formed such that its width W is smaller than its height H or length L. For convenience in representation of the drawings, the pin terminals23are arranged in five stages in the height direction of the housing22, and in four rows in the width direction thereof, i.e., there are twenty of them in total. All the pin terminals23are formed as rectangular pins. In this housing22the width W varies by large amounts depending on the number of the pin terminals23as shown inFIG. 7.

The entire housing22is formed of an insulating resin, and all the pin terminals23extend through the back plate26of the housing22in the thickness direction thereof, whereby the pin terminals23are electrically insulated from each other. Formed on the top plate24and the bottom plate25of the housing22are guide slopes24aand25afor facilitating the insertion of the receptacle connector10.

In the housing22, a plurality of vertical shield plates27constituting the plug side shield are arranged at equal intervals in the width direction of the housing22. Each vertical shield plate27is formed as a rectangular plate, and is arranged between pin terminals23adjacent to each other in the width direction of the housing22. The vertical shield plates27are arranged vertically, whereby each vertical row of pin terminals, consisting of five pin terminals23, is segregated by the vertical shield plates27(i.e., placed between vertical shield plates). The pin terminals23are of the same length, and are longer than the length of the vertical shield plates27. Right-angled terminal units29, which are forced into the housing20, are to be described next.

As shown inFIGS. 2 and 7, each right-angled terminal unit29is formed as a unit provided with a plurality of pin terminals23which are main components of the plug connector20, and tails23awhich are orthogonal to the pin terminals23to connect the pin terminals to the daughter board. Thus, the plug connector20is formed by a housing22, a plurality of (three or more) right-angled terminal units29, and a plurality of vertical shield plates27. Each vertical shield plate27is provided with a ground tail27a. A plurality of (e.g., two to five) ground tails27aare provided as needed at arbitrary positions of the vertical shield plate27a.

As shown inFIGS. 8 and 9, the back plate26of the housing22is provided with mounting passages26afor the pin terminals23of the right angled terminal unit, and other mounting passages26bfor the vertical shield plates27. Further, in the top plate24and the bottom plate25, there are provided guide grooves24band25bfor supporting the vertical shield plates27in a stable manner. Thus, as shown inFIGS. 7 through 9, by inserting the right-angled terminal units29and the vertical shield plates27into the housing22, the plug connector20is formed.

FIG. 10is a model diagram showing an example of the board layout of the plug connector20. In the drawing, the vertical axes a through e indicate the number of stages, and the horizontal axes1through6indicate the number of rows of pin terminals (signal pins)23. As shown in the drawing, the vertical shield plates27are connected to ground pins GP. The diagram shows by way of example a case in which two ground pins GP are provided, and a case in which four ground pins are provided.

The receptacle connector10comprises a plurality of contacts12each having a pair of contact members11(SeeFIG. 4(b)) adapted to come into electrical contact with each pin terminal23of the plug connector20, and a housing13(SeeFIG. 1)for holding the contacts12. Provided in the receptacle connector10are a plurality of horizontal shield plates14arranged in parallel to each other and constituting the receptacle side shield. The horizontal shield plates14intersect the vertical shield plates27of the plug connector20in a cross-like fashion. Slits (not shown) for allowing insertion of the vertical shield plates27are provided in the housing13and the horizontal shield plates14of the receptacle connector10.

The housing13of the receptacle connector10is composed of a plurality (five stages) of housing units131through135stacked together in a plurality of stages in the thickness direction of the housing13. For each of the housing units131through135, a horizontal shield14is integrally provided. In the lowermost stage of the housing13, there is provided a bottom housing unit130equipped with a horizontal shield plate14.

While there are various ways of integrally providing the horizontal shield plates with respect to the housing units, the horizontal shield plates14in this example are, from the viewpoint of productivity, integrated with the housing units130through135by insert molding. The respective horizontal shield plates14are placed in the middle portion with respect to the thickness direction of the housing units130through135.

Since the horizontal shield plates14are placed horizontally, their plane area is larger than that of the vertical shield plates27. Each of the horizontal shield plates14have the same plane area. The length of each horizontal shield plate14is such that it protrudes beyond the rear ends of the housing units131through135. As best seen inFIG. 1, the horizontal shield plates14are electrically connected by two short bars SB extending in a direction intersecting them at 90 degrees (vertical direction).

In this embodiment, the housing units are formed by four kinds of housing units: first housing units131and133, second housing units132and134, a lower stage housing unit130, and an upper stage housing unit135. Thus, when increasing or decreasing the number of stages, the number of first and second housing units is increased or decreased.

As shown inFIG. 4, formed on the joint surfaces of the housing units are male engagement portions17and female engagement portions18which engage with each other to join the housing units together. The male engagement portions17are formed as protrusions, and the female engagement portions18are formed as recesses allowing horizontal insertion of the male engagement portions17.

The male engagement portions17are provided in the lower stage housing unit130, and the second housing units132and134. The female engagement portions18are provided in the first housing units131and133and the upper stage housing unit135.

The male engagement portion17of the lower housing unit30is provided in the upper portion at one end thereof. The female engagement portions18of the second housing units132and134are provided in the upper and lower portions at one end thereof.

The female engagement portions18of the first housing units131and133are provided in the upper and lower portions at one end thereof. The female engagement portion18of the upper stage housing unit135is provided in the lower portion at one end thereof.

These engagement portions engage by a so-called “hook” system. As shown inFIG. 4, vertical insertion easily effects joining. Numeral15indicates guide protrusions for joining housing units to each other. Regarding the structure for this engagement, it is possible to adopt some other engagement structures.

In each of the housing units131through135, attachment holes19for the contacts12are arranged at intervals in the housing unit width direction. And, slits19aare provided between the attachment holes19.

The receptacle connector10is provided with a plurality of (five, in this embodiment) contact modules30respectively connected to the rear ends of the housing units131through135. Each contact module30is provided with a group of contacts11respectively forced in the attachment holes19, and a group of tails11aserving as leading conductors for connecting the contacts to the vertical board.

The portion of each contact module30other than the group of contacts11and the group of tails11aconstitutes a retaining portion30aformed by resin molding. Due to this retaining portion30aformed by resin molding, the contacts12are electrically insulated while being integrally retained in a horizontal row. Further, this retaining portion30ais tightly inserted between the upper and lower horizontal shield plates14. This allows each contact module30to be connected to the corresponding housing unit in a state in which it is retained in a stable manner.

FIG. 6is a model diagram showing an example of the board layout of the receptacle connector10. In the drawing, the vertical axes a through e indicate the number of stages, and the horizontal axes1through6indicate the number of row of pin terminals (signal pins)23. As it is already mentioned, the horizontal shield plates14are electrically connected by two short bars SB extending in a direction intersecting them at 90 degrees (vertical direction). Further, the horizontal shield plates are respectively connected to ground pins GP. At least one short bar SB suffices, and a plurality of short bars can be provided as needed.

The plurality of housing units130through135, which are the components of the housing13, the plurality of horizontal shield plates14constituting the receptacle side shields, and the plurality of contact modules30are prepared beforehand.

Thereafter, as shown inFIGS. 1 and 4, the second housing unit132of the second stage is superimposed on the upper surface of the first housing unit131of the first stage, and caused to slide from the rear to the front side, whereby the male engagement portion17is engaged with the female engagement portion18to effect positioning. Next, the first housing unit133is superimposed on the second housing unit132, and caused to slide backwards, whereby the male engagement portion17is engaged with the female engagement portion18to effect positioning.

In this assembly process, it is also possible to insert the second housing unit132between the first housing units131and133stacked one upon the other and engage them with each other.

Next, a similar operation is performed on the fourth and fifth stages, and the lower stage housing unit130is finally attached, whereby the receptacle housing13provided with a plurality of horizontal shield plates14is formed. After this, the contact modules30are forced in the respective housing units, whereby the receptacle connector10shown inFIG. 1is obtained.