Abstract:
An electronic apparatus includes a terminal holding mechanism that holds a terminal portion configured to conduct power from an external terminal, a terminal base that forms a part of the terminal holding mechanism, a partition wall having an open portion on a side, the partition wall separating the terminal portion and the terminal base, and a contact surface facing the open portion of the partition wall and provided integrally with the terminal base, the contact surface being electrically connected to the terminal holding mechanism.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application claims priority under 35 U.S.C. §119 to Japanese Patent Application No. 2010-116300, filed May 20, 2010. The contents of this application are incorporated herein by reference in their entirety. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a terminal device, an electronic apparatus, and an electronic apparatus production method. 
         [0004]    2. Description of the Related Art 
         [0005]    Japanese Patent Laid-Open Publication No. 2004-022405 discloses a terminal device (terminal base) that allows power or the like to be input to and output from an electronic apparatus such as an inverter. In the disclosed terminal device, a plurality of terminal screws are arranged side by side and are each surrounded by an insulating material (terminal base body). 
         [0006]    In this terminal device, a connecting wire is connected to the electronic apparatus by fastening the corresponding terminal screw in a state in which a U-shaped terminal or a round terminal of the connecting wire is clamped between the terminal screw and a base of the terminal screw. 
       SUMMARY OF THE INVENTION 
       [0007]    A terminal device according to an aspect of the present invention includes a terminal holding mechanism that holds a terminal portion configured to conduct power from an external terminal; a terminal base that forms a part of the terminal holding mechanism; a partition wall having an open portion on a side, the partition wall separating the terminal portion and the terminal base; and a flat contact surface facing the open portion of the partition wall and provided integrally with the terminal base, the contact surface being electrically connected to the terminal holding mechanism. 
         [0008]    A terminal device according to another aspect of the present invention includes a terminal screw formed of a conductive material; and a terminal base including a support surface having a screw hole with a thread groove corresponding to the terminal screw and a contact surface bent from the support surface. 
         [0009]    An electronic apparatus according to a further aspect of the present invention includes an electronic apparatus body having an electric circuit; and a terminal device provided in the electronic apparatus body. The terminal device includes a terminal holding mechanism that holds a terminal portion configured to conduct power from an external terminal, a terminal base that forms a part of the terminal holding mechanism, a partition wall having an open portion on a side, the partition wall separating the terminal portion and the terminal base, and a contact surface facing the open portion of the partition wall and provided integrally with the terminal base, the contact surface being electrically connected to the terminal holding mechanism. 
         [0010]    An electronic apparatus according to a further aspect of the present invention includes an electronic apparatus body having an electric circuit; and a terminal device provided in the electronic apparatus body. The terminal device includes a terminal screw formed of a conductive material, and a terminal base including a support surface having a screw hole with a thread groove corresponding to the terminal screw and a contact surface bent from the support surface. 
         [0011]    An electronic apparatus production method according to a still further aspect of the present invention includes the steps of assembling, in an electronic apparatus body, a terminal device including a terminal holding mechanism that holds a terminal portion configured to conduct power from an external terminal, a terminal base that forms a part of the terminal holding mechanism, a partition wall having an open portion on a side, the partition wall separating the terminal portion and the terminal base, and a flat contact surface facing the open portion of the partition wall and provided integrally with the terminal base, the contact surface being electrically connected to the terminal holding mechanism; conducting a product test on the electronic apparatus body while contacting a power supply pin with the contact surface of the terminal base through the open portion of the terminal device; and mounting an upper case that covers the electronic apparatus body after the product test. 
         [0012]    An electronic apparatus production method according to an even further aspect of the present invention includes the steps of assembling, in an electronic apparatus body, a terminal device including a terminal screw formed of a conductive material, and a terminal base including a support surface having a screw hole with a thread groove corresponding to the terminal screw and a contact surface bent from the support surface; conducting a product test on the electronic apparatus body while contacting a power supply pin with the contact surface from a side; and mounting an upper case that covers the electronic apparatus body after the product test. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The present invention will be described in further detail with reference to the accompanying drawings wherein: 
           [0014]      FIG. 1  schematically illustrates a production line for an electronic apparatus; 
           [0015]      FIG. 2  illustrates an inverter including terminal bases according to the present invention; 
           [0016]      FIG. 3  is an enlarged view of the terminal bases in the inverter; 
           [0017]      FIG. 4  is a cross-sectional view of a terminal base in the inverter; 
           [0018]      FIG. 5  illustrates a state in which the inverter is connected by an automatic connecting device; and 
           [0019]      FIG. 6  illustrates an electrical connecting method of the related art for a terminal screw and a pin. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0020]    An embodiment of the present invention will be described below with reference to the drawings. 
         [0021]    In the embodiment, the present invention is applied to a production line  50  for an inverter  32  serving as an example of an electronic apparatus. The inverter  32  receives an alternating current and outputs another alternating current having different voltage and frequency. 
         [0022]    As illustrated in  FIG. 1 , the production line  50  for the inverter  32  includes a production section  51  and a product test section  52 . In the production line  50 , an inverter  32  assembled in the production section  51  is transported by a conveyor to the product test section  52  and downstream sections. 
         [0023]    In the production section  51 , assembly components are assembled into an inverter  32  serving as a product. In the product test section  52 , various tests, such as a product test, are conducted on the inverter  32  assembled in the production section  51 . 
         [0024]    Next, a description will be given of a structure of the inverter  32  assembled in the production section  51 . 
         [0025]    As illustrated in  FIG. 2 , the inverter  32  assembled in the production section  51  includes a case  28  that houses devices such as power conversion circuits (a converter circuit and an inverter circuit) and radiation fins, and a terminal device  20  exposed from the case  28 . 
         [0026]    The terminal device  20  includes eight terminal portions, and serves to subject three-phase alternating currents input from three (three-phase) input terminal portions  14 A to power conversion and to output three-phase alternating currents having changed frequencies and voltages from three (three-phase) output terminal portions  14 B. Besides the input terminal portions  14 A and the output terminal portions  14 B, the terminal device  20  includes two braking-resistor connecting terminal portions  14 C. 
         [0027]    The braking-resistor connecting terminal portions  14 C are terminals connected to an internal braking resistor, and assist in braking of a motor connected to the inverter  32  by causing the braking resistor to consume regenerative energy of the motor. 
         [0028]    While the terminal device  20  is exposed out from the inverter  32  in the product test section  52 , an upper case  21  (see  FIG. 5 ) is attached in the product test section  52 . Thus, the devices that constitute the inverter  32 , including the terminal device  20 , are covered with the upper case  21  and the case  28 . 
       Terminal Device 
       [0029]    As illustrated in  FIG. 3 , the input terminal portions  14 A, the output terminal portions  14 B, and the braking-resistor connecting terminal portions  14 C are separated by partition walls  13  formed of an insulating material. 
         [0030]    A miswiring prevention cover  12  formed of an insulating material is attached above the braking-resistor connecting terminal portions  14 C. 
         [0031]    The function of the miswiring prevention cover  12  will be described. To use the inverter  32 , the user needs to insert terminals of an external device to be connected, from an opening above the partition walls  13  and to hold the terminals of the external device by terminal screws  1 , washers  3 , and L-shaped terminal bases  11 , as will be described below. However, since it is conceivable that the braking-resistor connecting terminal portions  14 C are less frequently used than the input terminal portions  14 A and the output terminal portions  14 B, the terminals of the external device, which should be connected to the input terminal portions  14 A or the output terminal portions  14 B, may be erroneously connected to the braking-resistor connecting terminal portions  14 C. The miswiring prevention cover  12  prevents such miswiring. 
         [0032]    The input terminal portions  14 A, the output terminal portions  14 B, and the braking-resistor connecting terminal portions  14 C have similar structures. 
         [0033]    As illustrated in  FIG. 3 , each of the terminal portions is surrounded on three sides by the partition walls  13 . One side of the terminal portion is not covered, thereby forming an open portion  13 A. On inner sides of the partition walls  13 , a terminal holding mechanism  15  including a terminal screw  1 , a washer  3 , and an L-shaped terminal base  11  is provided. 
         [0034]    That is, the terminal screw  1 , the washer  3 , and the L-shaped terminal base  11  are each formed of a conductor such as to achieve electrical connection to an electric circuit in the inverter  32 . Electrical connection can be made by contacting a conductor with the L-shaped terminal base  11 . 
         [0035]    The open portions  13 A of the input terminal portions  14 A, the output terminal portions  14 B, and the braking-resistor connecting terminals  14 C extend in the same direction. 
         [0036]    As illustrated in  FIG. 4 , each L-shaped terminal base  11  includes a support surface  11 A that supports the washer  3 , and a flat contact surface  11 B extending in a substantially up-down direction from the support surface  11 A via a bent portion  11 C bent about 90 degrees. The contact surface  11 B directly faces the above-described open portion  13 A. 
         [0037]    In other words, the L-shaped terminal base  11  is formed so that the direction of the normal to a plane that forms the contact surface  11 B is substantially equal to the direction in which the open portion  13 A extends. 
         [0038]    A length L 2  of the support surface  11 A and a length L 1  of the contact surface  11 B in the L-shaped terminal base  11  are substantially equal. 
         [0039]    The support surface  11 A has a thread groove  11 D in which the terminal screw  1  is screwed. 
         [0040]    An upper surface of the terminal screw  1  is shaped like a curved surface, and has a groove (not illustrated) to be engaged with a screw jig. 
         [0041]    The washer  3  is provided between a head portion of the terminal screw  1  and the L-shaped terminal base  11 . The washer  3  and the support surface  11 A clamp an external connection terminal  26 . For example, the external connection terminal  26  is an appropriate terminal having an annular terminal portion (round terminal), as illustrated in  FIG. 4 . 
         [0042]    The external connection terminal  26  is held by inserting the terminal screw  1  in an annular portion  27  so that the external connection terminal  26  is clamped by the washer  3  and the support surface  11 A. Also, the external connection terminal  26  is electrically connected to the electric circuit in the inverter  32 . 
       Configuration of Test Apparatus 
       [0043]    As illustrated in  FIG. 5 , a test apparatus  31  is provided in the product test section  52 . The test apparatus  31  covers the production line  50 , and includes eight power supply pins  2 , a pallet  22 , a pallet lifter  23 , a back-surface support member  24 , and horizontal conveyor belts  25 . 
         [0044]    The eight pins  2  are arranged side by side on an inner side wall  31 A of the test apparatus  31 , and can extend inward and outward in the lateral direction relative to the inner side wall  31 A. Further, the pins  2  are connected to a power supply or a test circuit (not illustrated). 
         [0045]    The pins  2  are shaped to have a relatively large diameter and to be provided with multiple fine projections at tips thereof. This secures sufficient contact areas between the pins  2  and the contact surfaces  11 B, and increases the force for pressing the pins  2  against the contact surfaces  11 B. Thus, even if vibration or the like occurs at power-on, undesirable discharging due to slight separation between the pin  2  and the contact surfaces  11 B is prevented. Hence, the production test can be conducted more stably. 
         [0046]    The pallet  22  is provided with a fixture (not illustrated) on which the inverter  32  on the conveyor is placed and fixed. Further, the pallet  22  is fixed on the pallet lifter  23 . 
         [0047]    The pallet lifter  23  can move the pallet  22  up and down by an actuator (not illustrated). The pallet lifter  23  is provided on the horizontal conveyor belts  25 . The pallet lifter  23  and the horizontal conveyor belts  25  position the pallet  22  according to the model of the inverter  32  so that the terminal device  20  of the inverter  32  opposes the pins  2 . 
         [0048]    The back-surface support member  24  supports the inverter  32  against the pressing forces of the pins  2  from the opposite side. The position of the back-surface support member  24  can be changed according to the model of the inverter  32 . Operations of the pins  2 , the pallet lifter  23 , and the horizontal conveyor belts  25  are controlled by a controller (not illustrated). 
         [0049]    Since the electronic apparatus and the production line  50  for the electronic apparatus according to the embodiment have the above-described configurations, an inverter  32  assembled in the production section  51  is transported into the test apparatus  31  of the product test section  52  by the conveyor. 
         [0050]    After being transported into the test apparatus  31 , the inverter  32  is fixed to the pallet  22 . 
         [0051]    Then, the pallet lifter  23  and the horizontal conveyor belts  25  are operated according to model information about the inverter  32  input to the controller beforehand, and the position of the pallet  22  is adjusted so that the pins  2  are aligned with the open portions  13 A of the terminal portions  14 A to  14 C. 
         [0052]    After that, the pins  2  extend from the inner side wall  31 A, ends of the pins  2  come into contact with the contact surfaces  11 B of the L-shaped terminal bases  11 , and power for the test is supplied from the input terminals  14 A, as illustrated in  FIG. 4 . The output from the output terminals  14 B is input to a test circuit in the test apparatus  31 , and a product test is conducted on the inverter  32 . 
         [0053]    The controller stores the acceptability criterion in the product test. An accepted inverter  32  is covered with an upper case  21  on the downstream side of the product test section  52 , and is then packaged. 
         [0054]    In this way, according to the embodiment, when the assembled inverter  32 , excluding the upper case  21 , on the production line is subjected to a product test during production, the protruding pins  2  are brought into contact with the vertical and flat contact surfaces  11 B from the side of the inverter  32 , whereby the inverter  32  is powered on and connected to the test circuit. 
         [0055]    For example, in a case in which a terminal screw head portion  100  shaped like a curved surface contacts a pin  101 , if the contact therebetween is insufficient because the contact area is relatively small, as illustrated in  FIG. 6 , an arc (or a spark) may occur during power supply. 
         [0056]    However, according to the embodiment, since the pins  2  contact the flat contact surfaces, discharging (arc discharging) is suppressed, compared with a case in which the pins  2  contact the convex surfaces like the head portions of the screws. Moreover, since the pins  2  need not be brought into contact with the inverter  32  from above, the height of the test apparatus  31  can be reduced. 
         [0057]    In addition, since the miswiring prevention cover  12  is provided above the braking-resistor connecting terminal portions  14 C, it is possible to prevent the external device terminal, which should be connected to the input terminal portion  14 A or the output terminal portion  14 B, from being erroneously connected to the braking-resistor connecting terminal  14 C. That is, in each of the terminal portions  14 A to  14 C during normal use, it is necessary to loosen the terminal screw  1  by a screw jig from above and to clamp the external terminal of the power supply or the like between the washer  3  and the L-shaped terminal base  11 . However, the braking-resistor connecting terminal portions  14 C are less frequently used than the input terminal portions  14 A and the output terminal portions  14 B. Hence, it is conceivable that the external terminal, which should be connected to the input terminal portion  14 A or the output terminal portion  14 B, will be erroneously connected to the braking-resistor connecting terminal portion  14 C. 
         [0058]    In the embodiment, since the pins  2  contact the contact surfaces  11 B from the side, not from above, even after the miswiring prevention cover  12  is assembled in the production section  51 , the pins  2  are pushed from the side through the open portions  13 A without removing the miswiring prevention cover  12  in the product test section  52 . This allows the product test to be carried out easily. 
         [0059]    While the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment. Appropriate modifications can be made without departing from the scope of the invention.