Abstract:
There is provided a relay module including: a power lead part connected to a power source; a connector lead part connected to a load; a relay switch interposed between the power lead part and the connector lead part, and electrically connected thereto; a control member for controlling the relay switch; and a molded part sealing at least ends of the power lead part and the connector lead part near the control member, the relay switch, and the control member.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   This application is based on Japanese Patent Application No. 2005-309500, the contents of which are hereby incorporated by reference. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a relay module and an electrical component unit, in particular, to a relay module using a relay switch for supplying electric power to a load, and an electrical component unit. 
   2. Description of the Related Art 
   As an electrical component unit on a vehicle using a semiconductor relay such as an intelligent power switch (IPS), a unit having a control board on which a connector and a semiconductor relay are packaged is well known. The connector connects the load such as a headlamp, a fog lamp, and various motors to the control board. The semiconductor relay supplies the electric power to the load corresponding to an instruction from the control board. 
   Such an electrical component unit on a vehicle is disclosed in Japanese Patent Application No. 2002-293201. The electrical component unit on a vehicle receives the control board and a semiconductor relay module packaged on the control board in a case main body, and a cover covers the case main body. Regarding the semiconductor relay module, the semiconductor relay is bonded to a die pad, and molded integrally with a lead wire connected to the control board, a lead wire for the connector, and a lead wire for a battery. The semiconductor relay module and electronic parts for controlling the semiconductor relay module are packaged on the control board. 
   However, according to the electrical component unit on a vehicle described above, the control board is separated into a power part where the semiconductor relay module is packaged and a control part where the electronic parts are packaged. Therefore, a packaging area and a packaging volume on the control board are increased. A useless space is generated at the control part. Thus, the electrical component unit tends to be upsized. In such a configuration, because the number of parts is large, an assembling structure is complex, and a packaging process wastes time. 
   Accordingly, an object of the present invention is to provide a relay module and an electrical component unit that is able to be downsized, and save weight. 
   SUMMARY OF THE INVENTION 
   In order to attain the object, according to the present invention, there is provided a relay module including: 
   a power lead part connected to a power source; 
   a connector lead part connected to a load; 
   a relay switch interposed between the power lead part and the connector lead part, and electrically connected thereto; 
   a control member for controlling the relay switch; and 
   a molded part sealing at least ends of the power lead part and the connector lead part near the control member, the relay switch, and the control member. 
   According to another aspect of the present invention, there is provided an electrical component unit including: 
   a relay module described above; 
   a connector connected to a wire from a load; and 
   a receiving chamber for receiving the relay module and the connector, said relay module and the connector are electrically connected. 
   These and other objects, features, and advantages of the present invention will become more apparent upon reading of the following detailed description along with the accompanied drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded perspective view showing an electric coupling box receiving relay blocks; 
       FIG. 2  is an exploded perspective view of the relay block in  FIG. 1 ; 
       FIG. 3  is a perspective view showing an outline structure of a relay module according to the present invention; 
       FIG. 4  is an equivalent circuit diagram of the relay module in  FIG. 3 ; 
       FIG. 5  is an explanatory view showing how the relay block is received in the electric coupling box; 
       FIG. 6A  is an explanatory view showing how the relay module is assembled with a case main body; 
       FIG. 6B  is an explanatory view showing how the relay module is assembled with a block member; and 
       FIG. 6C  is an explanatory view showing a finish of the assembling. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   First Embodiment 
   A first embodiment of an electric coupling box  1  including a relay module and an electrical component unit according to the present invention will be described with reference to  FIGS. 1 to 4 . 
   As shown in  FIG. 1 , the electric coupling box  1  includes a box main body  2  having a substantially rectangular tray shape, a cover  3  covering an upper opening of the box main body  2 , and a plurality of relay blocks  10  as the electrical component units. The box main body  2  includes a plurality of installation parts  4  for electric parts such as relay blocks  10  and relays  20  at an upper side thereof. The box main body  2  includes another installation parts (not shown) for connectors  30  connected to wires from loads at a lower side thereof, where the connectors  30  are electrically connected to the electric parts installed on the installation parts  4 . The box main body  2  and the installation parts are integrally molded with insulating synthetic resin. A through hole for a lead wire is formed on the installation parts  4  for allowing the lead part of the electric part to project from a specific position. 
   As shown in  FIG. 2 , the relay block  10  includes a case main body  11  having a substantially rectangular tray shape, a cover  12  covering the case main body  11 , and a relay module  40 . The case main body  11  and the cover  12  are made of insulating synthetic resin. The case main body  11  includes an installation part (not shown) for installing the relay module  40  of the present invention. A through hole is formed on the installation part for allowing the lead part of the relay module  40  to project from a specific position of the installation part. 
   Incidentally, in this first embodiment, the one relay block  10  receives the one relay module  40 . However, the relay block may receive a plurality of relay modules  40 . In this case, a plurality of installation parts is formed on the relay block  10 , and a size of the relay block  10  is changed. 
   As shown in  FIGS. 3 and 4 , the relay module  40  includes power lead parts  41 A,  41 B for connected to a power source, a plurality of connector lead parts  42  for connected to loads L 1 , L 2 , L 3 , L 4 , a semiconductor relay switches  43 A,  43 B interposed between and electrically connected to the power lead parts  41 A,  41   b  and the connector lead parts  42 , a control unit  44  for controlling the semiconductor switches  43 A,  43 B, and a molding part  47  at least sealing ends near the control unit  44  of the power lead parts  41 A,  41 B, and connector lead parts  42 , the semiconductor relay switches  43 A,  43 B, and the control unit  44 . 
   Each of the power lead parts  41 A,  41 B is installed on the relay block  10 . Then, the relay block  10  is installed on the electric coupling box  1  and the power lead parts  41 A,  41 B are inserted into holes of a connector  30  and connected to terminals of the connector  30  so that the power lead parts  41 A,  41 B are connected to the power source through wires connected to the terminals. 
   Each of the connector lead parts  42  is installed on the relay block  10 . Then, the relay block  10  is installed on the electric coupling box  1  and the connector lead parts  42  are inserted into the insertion holes of the connector  30  to be connected to the terminals of the connector  30 . Thus, the connector lead parts  42  are electrically connected to the loads L 1 , L 2 , L 3 , L 4  which for example drives a headlamp, or a motor for driving a wiper through wires connected to the terminals. 
   The power lead parts  41 A,  41 B and the connector lead parts  42  are made of metal plate such as aluminum, copper, copper-iron alloy, copper-iron-phosphorus alloy, copper-chromium alloy, copper-nickel-silicon alloy, copper-tin alloy, nickel-iron alloy, iron-nickel-cobalt alloy, copper-stainless steel alloy. Further, nickel-plated, silver-plated, or gold-plated metal plate is acceptable. 
   Further, because high current flows through the power lead parts  41 A,  41 B and the connector lead parts  42 , the widths thereof are wide. Electric power is supplied to the connector lead parts  42  from the power lead parts  41 A,  41 B corresponding to switching operation of the semiconductor relay switches  43 A,  43 B. 
   An intelligent power switch, MOSFET (metal oxide silicon field effect transistor), or the like is used for the semiconductor relay switches  43 A,  43 B and installed on surfaces of the power lead parts  41 A,  41 B. Because drain electrodes as backside electrodes are electrically connected to die pads  41 C of the power lead parts  41 A,  41 B, current capacities are relatively greater than those of surface electrodes of the semiconductor relay switches  43 A,  43 B and the high current can flow through the power lead parts  41 A,  41 B. 
   Incidentally, in the first embodiment, the semiconductor relay is used as a relay switch. However, the present invention is not limited to this. Various relays such as a mechanical relay or a hybrid relay can be used. 
   The control unit  44  includes a control member  44   a  having an MPU (microprocessor unit), an LSI (large-scale integrated circuits) and the like, and a control board  44   b  having the control member  44   a  and electric parts. 
   The control member  44   a  is electrically connected to gate electrodes of the semiconductor relay switches  43 A,  43 B, and controls the switching operations of the semiconductor relay switches  43 A,  43 B by outputting high/low signals as control signals to the gate electrodes. 
   The control board  44   b  includes a surface electrode  44   c  and a surface electrode at the connector side  44   d . The surface electrode  44   c  and source electrodes of the semiconductor relay switches  43 A,  43 B are wire-bonded and electrically connected to each other. Similarly, the surface electrode at the connector side  44   d  and the connector lead parts  42  are wire-bonded and electrically connected to each other. The surface electrode  44   c  at the power lead part  41 A side is electrically connected to the surface electrode at the connector side  44   d  by wiring patterns branching to the loads L 1 , L 2  to which the semiconductor relay switch  43 A supplies the power. Also, the surface electrode  44   c  at the power lead part  41 B side is electrically connected to the surface electrode at the connector side  44   d  by wiring patterns branching to the loads L 3 , L 4  to which the semiconductor relay switch  43 B supplies the power. 
   According to such a configuration of the control board  44   b , a power supplying line is formed for supplying the loads L 1 , L 2 , L 3 , L 4  respectively through the connector lead parts  42  from the semiconductor relay switches  43 A,  43 B corresponding to the switching operations of the semiconductor relay switches  43 A,  43 B controlled by the control member  44   a.    
   Incidentally, aluminum wire, gold wire, copper wire, or a ribbon of those can be used as a bonding wire connecting the power lead parts  41 A,  41 B and the control unit  44 , the control unit  44  and the connector lead parts  42 . 
   According to the first embodiment, a control unit having the control board  44   b  on which the control member  44   a  is installed is mounted on a plate-shaped frame member  46 . However, if the control member  44   a  can be directly wire-bonded to the power lead parts  41 A,  41 B, the connector lead parts  42 , and the semiconductor relay switches  43 A,  43 B, the control board  44   b  is not required. 
   In the molding part  47 , ends of the power lead parts  41 A,  41 B and the connector lead parts  42  near the control unit  44 , the semiconductor relay switches  43 A,  43 B, and the control unit  44  are plastic-molded in a substantially box shape. Namely, the power lead parts  41 A,  41 B and the connector lead parts  42  are extended from one sidewall of the molding part  47 . 
   Thus, an outside shape of the relay module  40  is composed of an outside shape of the molding part  47 , the power lead parts  41 A,  41 B and the connector lead parts  42  extended from the molding part  47 , and the control unit  44  is molded in the molding part  47 . Therefore, it is not necessary that the relay module  40  is installed on a substrate and received in a case member. Therefore, the relay module  40  can be downsized and save weight. 
   Next, a forming of the relay module  40  will be explained. First, power lead parts  41 A,  41 B, four connector lead parts  42 , a lead member  46  used for the relay module  40  are formed in a lead frame in a specific shape by stamping, etching or the like. Then, the semiconductor relay switches  43 A,  43 B are respectively installed on the die pads of the lead frame. The control unit  44  is installed on the lead member  46 . The semiconductor relay switches  43 A,  43 B and the control unit  44 , the semiconductor relay switches  43 A,  43 B, and the lead member  46  are respectively wire-bonded. After the molding part  47  is formed on the lead frame by such as a transfer mold, extra parts of the lead breaks are cut. Thus, the relay module  40  is formed. 
   Next, an installation example of the relay module  40  and the relay blocks  10  to the electric coupling box will be explained with reference to  FIGS. 1 and 2 . 
   As shown in  FIG. 2 , the relay module  40  is installed on the installation part of the case main body  11 , and the cover  12  covers the case main body  11 , so that the relay module  40  is received and fixed to an interior of the relay block  10 . Thus, the relay module installation process is simple and time for the installation can be reduced. 
   As shown in  FIG. 1 , two relay blocks  10  are installed on the installation parts  4  of the box main body  2 , and the cover  3  covers the box main body  2 , so that the two relay blocks  10  are received and fixed to an interior of the electric coupling box  1 . The connectors  30  connected to the wires from the loads are installed on the connection installation parts from a lower side of the electric coupling box  1 . Thus, the connectors  30  and the relay modules  40  are electrically connected to each other, and the connector lead parts  42  and the loads L 1 , L 2 , L 3 , L 4  are electrically connected to each other through the wires connected to the connectors  30 . 
   When supplying the power to the loads L 1 , L 2 , the control member  44   a  of the control unit  44  switches on the semiconductor relay switch  43 A and the power is supplied to the loads L 1 , L 2  through the semiconductor relay switch  43 A from the power lead part  41 A. Similarly, when supplying the power to the loads L 3 , L 4 , the control member  44   a  of the control unit  44  switches on the semiconductor relay switch  43 B and the power is supplied to the loads L 3 , L 4  through the semiconductor relay switch  43 B from the power lead part  41 B. 
   According to the relay module  40  of the first embodiment, the molding part  47  seals the ends of the power lead parts  41 A,  41 B, connector lead parts  42  near the control member  44   a , the semiconductor relay switches  43 A,  43 B, and the control member  44   a . Therefore, no useless space such as a control board is generated. Therefore, the relay module  40  can be downsized, and save weight. Further, because a member for connecting the conventional relay module and the control board is not required, cost of the relay module  40  can be reduced. 
   Further, according to the electronic component unit of the first embodiment, because using the downsized, light-weighted relay module  40 , the relay block  10  can be downsized, and save weight. Further, because the relay module  40  is downsized and light-weighted, a larger number of relay modules  40  can be installed. Therefore, it makes easier to exchange the relay modules  40  when a design changes. Thus, maintenanceability of the relay module  40  can be improved. 
   Incidentally, if a plurality of or some kinds of control units  44  are plastic molded on the relay module  40 , only the relay module  40 , which is required to change owing to the design change, can be changed. Therefore, the maintenanceability of the relay module  40  is further improved. 
   Further, according to the first embodiment, the power lead parts  41 A,  41 B and the connector lead parts  42  are extended from one side of the molding part  47 . However, various forms can be used. For example, the power lead parts  41 A,  41 B and the connector lead parts  42  are fully molded so as to be electrically connected. 
   Further, according to the relay module  40  described above, the power is supplied to the loads through the two of connector lead parts  42  of each of the power lead parts  41 A,  41 B. However, the present invention is not limited to this. Various forms can be used. For example, the power lead parts  41 A,  41 B and the connector lead parts  42  are respectively connected in one to one relationships. For another example, two of the connector lead parts  42  are respectively connected to a power line and a control line. 
   Further, in the first embodiment, the semiconductor relay switches  43 A,  43 B correspond to the two of power lead parts  41 A,  41 B. However, the number of those can be optionally set. 
   Second Embodiment 
   One embodiment of the box main body  2  including a relay block having the relay module  40  of the first embodiment and the conventional relay block will be explained. 
   In  FIG. 5 , the electric coupling box  1  includes the box main body  2 , the cover  3  (see  FIG. 1 ), and the relay block installed corresponding to a product or the conventional relay block  60 . 
   The box main body  2  includes a plurality of installation parts  4  for electric parts such as relay blocks  10  and relays  20  at an upper side thereof. The box main body  2  includes another installation parts (not shown) for connectors  30  connected to wires from loads at a lower side thereof, where the connectors  30  are electrically connected to the electric parts installed on the installation parts  4 . A through hole for a lead wire is formed on the installation parts  4  for allowing the lead part of the electric part to project from a specific position. 
   As shown in  FIG. 6A to 6C , the relay block  10  includes a block member  16  formed corresponding to the shape of the installation parts  4  for connecting to the installation parts  4  of the box main body  2 , a cover case  17  to be installed on the block member for receiving the relay module  40 , and the relay module  40 . 
   The block member  16  and the cover case  17  are made of insulating synthetic resin. The block member  16  includes a plurality of insertion holes  16   a  to which power lead parts  41 A,  41 B and the connector lead parts  42  are inserted, a fitting member  16   b  into which the cover case  17  is fitted, and an engaging member  16   c  for engaging with an engaging member (not shown) mounted on an inner wall of the installation part  4 . 
   The cover case  17  includes a press-fitting part  17   a  into which the relay module  40  is press-fitted, an extending part  17   b  for covering leads of the relay module  40  fitted into the press-fitting part  17   a , and fitted into the fitting member  16   b , and an identification part  17   c  identifying the relay module  40  to be press-fitted into the press-fitting part  17   a.    
   The press-fitting part  17   a  is formed in a shape to allow the relay module  40  to be press-fitted into the cover case  17  having a substantially box shape. For preventing the relay module  40  from falling out, a projection, a catch, or the like is formed in an interior of the press-fitting part  17   a.    
   The extending part  17   b i s extended from the press-fitting part  17   a  to cover the leads of the relay module  40  fitted into the press-fitting part  17   a . An interior of the extending part  17   b  is formed in a shape to allow the relay module  40  to pass through. Thus, the extending part  17   b  protects the leads of the relay module  40 , so that a trouble that the leads are bent at assembling is prevented. Accordingly, handling ability at the assembling of the relay module  40  with the cover case  17  is improved. 
   The identification part  17   c  has a color corresponding to a duty ratio of the relay module  40  or a product number of the relay module  40 . Regarding the color, various forms can be accepted. For example, the color is the same as a color of a material of the cover case  17 . Alternatively, the color is the color painted on a whole or a part of surface of the cover case  17 . Alternatively, the color is a color of a label or the like stuck on the cover case  17 . Thus, the identification part  17   c  prevents workers from miss-assembling the relay module  40 . 
   Next, an assembling example of the relay blocks  10  of the second embodiment will be explained with reference to  FIG. 6 . 
   As shown in  FIG. 6A , the relay module  40  is pressed into the press-fitting part  17   a  of the cover case  17  having the identification part  17   c  corresponding to the relay module  40 . Then, as shown in  FIG. 6B , the extending part  17   b  is fitted into the fitting member  16   b , and the leads of the relay module  40  are inserted into the insertion holes  16   a . Thus, as shown in  FIG. 6C , the relay blocks  10  is assembled. Then, the relay module  40  is fitted into and installed on the installation parts  4  of the box main body  2 . 
   The conventional relay block  60  includes a case main body  61  and the block member  16 . The case main body  61  includes a control board having a connector and a semiconductor relay. Similar to the relay block  10 , the case main body  61  is installed on the block member  16 , and the conventional relay block  60  is assembled. Then, the conventional relay block  60  is fitted into and installed on the installation parts  4  of the box main body  2 . 
   According to the relay blocks  10  of the second embodiment, because the downsized, light-weighted relay module  40  is used, the relay block  10  can be downsized and save weight. Further, because the relay module  40  is downsized and light-weighted, a larger number of relay modules  40  can be installed. Therefore, it makes easier to exchange the relay modules  40  when a design changes. Thus, maintenanceability of the relay module  40  can be improved. 
   Further, the block member  16  is used for the relay block  10  and the conventional relay block  60 . Therefore, the box main body  2  and a production line work for common use. Therefore, cost of the product can be reduced. 
   Although the present invention has been fully described by way of example with reference to the accompanying drawings, it is to be understood that various changes and modifications will be apparent to those skilled in the art. Therefore, unless otherwise such changes and modifications depart from the scope of the present invention hereinafter defined, they should be construed as being included therein.