Abstract:
A railway vehicular power converter adapted to be fixed beneath a floor of a railway vehicle has a power conversion unit, a housing, and a plurality of L-shaped securing members provided at upper end parts of an outer surface of the housing for fixing beneath the floor of the railway vehicle. The plurality of securing members is reinforced by reinforcing members provided inside the housing and attached behind the surface of the housing where the securing members are disposed. Each of the reinforcing members has a C-channel having a length substantially the same as a length of the housing in a shorter direction thereof, and has two edges in the shorter direction bent at least once.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a railway vehicular power converter. 
         [0003]    2. Description of the Related Art 
         [0004]    A power converter is conventionally incorporated in the railway vehicle body of, for example, rolling stock. The power converter is equipped with an inverter and converter for converting an overhead wire power supplied from a pantograph into a predetermined AC power. A railway vehicle drive motor is controlled by this AC power (Japanese Patent Application Publication No. 2004-87711). 
         [0005]    Such a conventional power converter is described with reference to  FIGS. 11 and 12 . 
         [0006]      FIG. 11  is a planar cross-sectional view of the conventional power converter. Reference numeral  101  represents a housing (power converter),  102  a power conversion unit,  103  electrical component groups,  104  a blower, and  105  a securing plate. 
         [0007]    The housing  101  is in the shape of a rectangular cuboid. The power conversion unit  102  configured by a converter and inverter is disposed in the vicinity of the center of the housing  101 . The electrical component groups  103  are disposed at either side surface of the power conversion unit  102  so as to sandwich the power conversion unit  102 . The blower  104  is installed at a front surface of the housing  101 . The L-shaped securing plate  105  is welded to each of four corners of the housing  101 . 
         [0008]    Overhead wire power supplied from a pantograph is converted into a predetermined AC power by the power conversion unit  102 . Because the power conversion unit  102  generates heat, outside air is introduced from the rear surface side of the housing  101  and released to the front surface side of the housing  101  by the blower  104  to cool the power conversion unit  102  with a forced draft of the air. As will be described hereinafter, the housing  101  is attached to a railway vehicle body by fastening the securing plate  105  by a bolt and the like. 
         [0009]      FIG. 12  is a side view of the conventional power converter. In this diagram the housing (power converter)  101  is suspended from the railway vehicle body. Reference numeral  106  represents a bolt,  109  a nut,  107  a bracket, and  108  a railway vehicle body. 
         [0010]    The L-shaped bracket  107  is provided at each of four sections under a floor of the railway vehicle body  108  so as to face the securing plate  105  of the housing  101 . Each of the brackets  107  and the securing plate  105  are fastened and secured to each other by the bolt  106  and the nut  109 . As a result, the housing  101  is suspended under the floor of the railway vehicle body  108 . 
         [0011]    The conventional vehicular power converter has the following problems. 
         [0012]    Because the conventional vehicular power converter is subject to shock due to vibration, the housing (power converter) and the railway vehicle body need to be fixed to each other. However, the housing needs to be small due to the limited space under the floor of a railway vehicle for installing the housing. Moreover, the housing needs to be light due to requests for minimizing labor in maintaining and inspecting the power converter and for improving the workability of maintaining and inspecting the power converter. 
         [0013]    However, in the conventional vehicular power converter, in order to increase the strength of a secured section between the housing and the railway vehicle body, a sheet metal for configuring the entire housing including the railway vehicle body and the securing part needs to be thickened, which increases the mass of the entire housing. 
       SUMMARY OF THE INVENTION 
       [0014]    On the other hand, thinning the sheet metal of the housing for the purpose of reducing the mass of the housing lowers the strength of the secured section. 
         [0015]    The present invention was conceived in view of the problems described above, and an object thereof is to improve the strength of the secured section between the railway vehicle body and the railway vehicular power converter. 
         [0016]    In order to achieve the object described above, the present invention is a railway vehicular power converter having a housing capable of being fixed beneath a floor of a railway vehicle and having a storage space for storing a rectangular cuboid power conversion unit. The railway vehicular power converter has L-shaped first and second securing members provided respectively at upper end parts of outer front and outer rear surfaces of the housing and secured under the floor of the railway vehicle. The first securing member provided on the outer front surface of the housing is reinforced by a first reinforcing member provided inside the housing. The first reinforcing member is a C-channel having the same length as the length of the housing in a shorter direction thereof and attached to an inner upper end corner behind the front surface of the housing provided with the first securing member. The first securing member has two edges in the shorter direction bent at least once. The second securing member provided on the outer rear surface of the housing is reinforced by a second reinforcing member provided inside the housing. The second reinforcing member is a C-channel having the same length as the length of the housing in a shorter direction thereof and attached to an inner upper end corner behind the rear surface of the housing provided with the second securing member. The second securing member has two edges in the shorter direction bent at least once. 
         [0017]    According to the present invention, in the above-described configuration, an L-shaped third securing member is provided at an upper end part of an outer side surface of the housing and is secured under the floor of the railway vehicle. The third securing member is reinforced by a third reinforcing member provided inside the housing. The third reinforcing member is a C-channel having the same length as the length of the housing in a longer direction thereof, and attached to an inner upper end corner behind the side surface of the housing provided with the third securing member. The third securing member has two edges in the longer direction bent at least once. 
         [0018]    According to the present invention, in the above-described configuration, L-shaped third and fourth securing members are provided at upper end parts of outer side surfaces of the housing in which the side surfaces of the housing are facing each other, and are secured under the floor of the railway vehicle. 
         [0019]    The third securing member provided on one of the side surfaces of the outer side surface of the housing is reinforced by a third reinforcing member provided inside the housing. The third reinforcing member is a C-channel having the same length as the length of the housing in a longer direction thereof and attached to an inner upper end corner behind the side surface of the housing provided with the third securing member. The third reinforcing member has two edges in the longer direction bent at least once. 
         [0020]    The fourth securing member on the other side surface of the outer side surface of the housing is reinforced by a fourth reinforcing member provided inside the housing. The fourth reinforcing member is a C-channel having the same length as the length of the housing in a longer direction thereof, and attached to an inner upper end corner behind the side surface of the housing provided with the fourth securing member. The fourth reinforcing member has two edges in the longer direction bent at least once. 
         [0021]    Moreover, in order to achieve the object described above, the present invention is a railway vehicular power converter having a housing to be secured beneath a floor of a railway vehicle and having a storage space for storing a rectangular cuboid power conversion unit. L-shaped first, second, and third securing members are provided respectively at upper end parts of an outer front surface, an outer rear surface, and an outer side surface of the housing and secured under the floor of the railway vehicle. The third securing member provided on the outer side surface of the housing is reinforced by a third reinforcing member provided inside the housing. The third reinforcing member is a C-channel having the same length as the length as the length of the housing in a longer direction thereof, and attached to an inner upper end corner behind the side surface of the housing provided with the third securing member. The third reinforcing member has two edges in the longer direction bent at least once. 
         [0022]    In order to achieve the object described above, the present invention is a railway vehicular power converter having a housing to be secured under a floor of a railway vehicle and having a storage space for storing a rectangular cuboid power conversion unit. L-shaped third and fourth securing members are provided respectively at upper end parts of an outer side surface of the housing in which the side surfaces are facing each other, and are secured under the floor of the railway vehicle. 
         [0023]    The third securing member provided on one of the side surfaces of the outer side surface of the housing is reinforced by a third reinforcing member provided inside the housing. The third reinforcing member is a C-channel having the same length as the length of the housing in a longer direction thereof, and attached to an inner upper end corner behind the side surface of the housing provided with the third securing member. The third reinforcing member has two edges in a longer direction bent at least once. 
         [0024]    The fourth securing member provided on the other side surface of the outer side surface of the housing is reinforced by a fourth reinforcing member provided inside the housing. The fourth reinforcing member is a C-channel having the same length as the length of the housing in a longer direction thereof, and attached to an inner upper end corner behind the side surface of the housing provided with the fourth securing member. The fourth securing member has two edges in the longer direction bent at least once. 
         [0025]    According to the present invention, in the above-described configuration, the reinforcing members are bent into a hook shape. 
         [0026]    Furthermore, according to the present invention, in the above-described configuration, the securing members and the reinforcing members have the same sheet thickness. 
         [0027]    According to the present invention, in the above-described configuration, a drive motor is controlled by using the railway vehicular power converter having the configuration described above. 
         [0028]    The present invention can realize improvement of the strength of the secured section between a railway vehicle body and the railway vehicular power converter. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0029]      FIG. 1  is a configuration diagram of an entire rolling stock to which first to third embodiments of the present invention are applied. 
           [0030]      FIG. 2  is a side view of an exterior of a railway vehicular power converter according to the first embodiment of the present invention; 
           [0031]      FIG. 3  is a plan view of the exterior of the railway vehicular power converter according to the first embodiment of the present invention; 
           [0032]      FIG. 4  is a rear view of the exterior of the railway vehicular power converter according to the first embodiment of the present invention; 
           [0033]      FIG. 5  is a cross-sectional view showing a rear surface side of the railway vehicular power converter according to the first embodiment of the present invention; 
           [0034]      FIG. 6  is an enlarged side view of a reinforcing member of the railway vehicular power converter according to the first embodiment of the present invention; 
           [0035]      FIG. 7  is a front view of the reinforcing member of the railway vehicular power converter according to the first embodiment of the present invention; 
           [0036]      FIG. 8  is a cross-sectional view showing a rear surface side of a railway vehicular power converter according to a second embodiment of the present invention; 
           [0037]      FIG. 9  is a front view of a reinforcing member of the railway vehicular power converter according to the second embodiment of the present invention; 
           [0038]      FIG. 10  is a cross-sectional view showing a rear surface side of a railway vehicular power converter according to a third embodiment of the present invention; 
           [0039]      FIG. 11  is a planar cross-sectional view of a conventional vehicular power converter; and 
           [0040]      FIG. 12  is a side view of the conventional vehicular power converter. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0041]    Embodiments of the present invention are described hereinafter with reference to the drawings. The following description is merely illustrative, and therefore the present invention should not be limited thereto. In other words, a person skilled in the art can make many modifications within the technical idea of the present invention. 
         [0042]    First of all, an entire configuration of a rolling stock to which first to third embodiments of the present invention are applied is described with reference to  FIG. 1 . 
         [0043]      FIG. 1  is a configuration diagram of an entire rolling stock. Reference numeral  1  represents pantographs,  2  a railway vehicle body,  3  wheels,  4  a housing (power converter),  5  a power conversion unit, and  16  carriages. 
         [0044]    As shown in  FIG. 1 , an ordinary rolling stock has the pantograph  1  installed at an upper part of the railway vehicle body  2 . Each carriage  16  formed on the continuous wheels  3  is provided under a floor of the railway vehicle body  2  to support the railway vehicle body  2 . The housing  4  is installed between the carriages  16  provided under the floor of the railway vehicle body  2 . The housing  4  is suspended under the floor of the railway vehicle body  2 . The power conversion unit  5  configured by an inverter, converter and the like is stored in the housing  4 . 
         [0045]    Here, a traveling direction of the railway vehicle body  2  is illustrated as a front surface side of the railway vehicle body  2 , and a direction opposite to the traveling direction is illustrated as a rear surface side of the railway vehicle body  2 . 
         [0046]    Next are described the operations of the rolling stock of  FIG. 1  driven by a DC motor. 
         [0047]    First, the power conversion unit  5  receives DC power from the pantograph  1 . Then, the DC current is converted into AC power by switching a semiconductor element (not shown) provided inside the power conversion unit  5 . The AC power obtained as a result of the conversion drives a railway vehicle drive motor (not shown) to rotate the wheels  3 , allowing the rolling stock to start traveling. 
         [0048]    These are the entire configuration and the operations of the rolling stock. 
         [0049]    Next, exteriors of the railway vehicular power converter according to the first embodiment are described with reference to  FIGS. 2 to 4 . 
         [0050]      FIG. 2  is a side view of an exterior of the railway vehicular power converter according to the first embodiment of the present invention.  FIG. 3  is a plan view of the same.  FIG. 4  is a rear view of the same. Reference numeral  6  represents securing plates (securing members),  7  mounting holes,  11  a front surface,  12  a rear surface,  13  side surfaces,  14  an opposing planar surface, and  15  a bottom surface. 
         [0051]    As shown in  FIG. 1 , once the rectangular cuboid housing  4  is suspended and secured under the floor of the railway vehicle body  2 , the opposing planar surface  14  of the housing  4  faces a floor surface of the railway vehicle body  2 . 
         [0052]    A front surface-side upper end part and rear surface-side upper end part of the housing  4  are installed with the securing plates  6  respectively. Further, two securing plates  6  are installed at a predetermined interval in an upper end part of one of the side surfaces  13  of the housing  4 . Each of the securing plates  6  is in the form of a plate (L-shaped) and has the mounting hole  7  formed at the center thereof in order to pass a bolt (not shown) therethrough. The securing plates  6  are attached to the housing  4  by, for example, welding or rivets. 
         [0053]    The power converter is secured to the railway vehicle body  2  by a total of four securing plates  6 . Specifically, the bolts (not shown) are inserted into the mounting holes  7  formed in the securing plates  6  and fastened with nuts (not shown). In this manner, the power converter is secured under the floor of the railway vehicle body  2 , in a suspended manner. 
         [0054]    Next, a reinforcing member  8  that is applied inside the housing  4  of the railway vehicular power converter of the first embodiment of the present invention is described with reference to  FIG. 5 . 
         [0055]      FIG. 5  is a cross-sectional view showing the rear surface side of the railway vehicular power converter according to the first embodiment of the present invention. Reference numeral  8  represents a reinforcing member. 
         [0056]    As shown in  FIG. 5 , the C-channel-shaped reinforcing member  8  is installed at an upper end part on the inner side surface  13  of the housing  4 . The securing plates  6  are positioned on the outer side surface  13  of the housing  4 . 
         [0057]    Edges on the either side of the reinforcing member  8  in a longer direction are bent (twice) as will be described hereinafter. Note that the reinforcing member  8  is attached to an inner surface of the housing  4  by, for example, welding or rivets. 
         [0058]    The configuration of this reinforcing member  8  is described in further detail with reference to  FIGS. 6 and 7 . 
         [0059]      FIG. 6  is an enlarged side view of the reinforcing member of the railway vehicular power converter according to the first embodiment of the present invention.  FIG. 7  is a front view of the reinforcing member. Reference numeral  9  is a first bent part and  10  a second bent part. 
         [0060]    As shown in  FIG. 6 , the first bent part  9  and the second bent part  10  are formed at either end parts of the reinforcing member  8 . In other words, these end parts of the reinforcing member  8  are bent into a hook shape. Examples of the bending method include a roll forming method and press brake method. 
         [0061]    As shown in  FIG. 7 , the total length of the reinforcing member  8  is set at a length equivalent to the total horizontal length of a side surface part of the housing  4 . Therefore, when attaching the reinforcing member  8  to the inner surface of the housing  4  as shown in  FIG. 5 , the reinforcing member  8  can be installed along the side surface part of the housing  4 . Note that the sheet thickness of the reinforcing member  8  is substantially the same as that of the housing  4 . 
         [0062]    In the above-described vehicular power converter of the first embodiment of the present invention, the strength of securing the housing  4  to the railway vehicle body  2  can be improved by installing the reinforcing member  8  on the inside of the side surface part of the housing  4  where the securing plates  6  for securing the housing  4  to the railway vehicle body  2  are installed. 
         [0063]    Because the reinforcing member  8  is bent twice, the strength of securing the housing  4  to the railway vehicle body  2  can be improved without increasing the sheet thicknesses of the housing  4  and the securing plates  6 . 
         [0064]    Accordingly, the strength of securing the housing  4  to the railway vehicle body  2  can be improved, while reducing the size and weight of the housing  4 . 
         [0065]    A second embodiment of the present invention is described next. The sections same as those of the first embodiment are simplified, and the sections different from those of the first embodiment are described in detail. 
         [0066]    The exterior of the housing  4  of the second embodiment is identical to that of the first embodiment. The internal structure of the housing  4  is different from that of the first embodiment and is therefore described with reference to  FIG. 8 . 
         [0067]      FIG. 8  is a cross-sectional view showing the rear surface side of the railway vehicular power converter according to the second embodiment of the present invention. 
         [0068]    As shown in  FIG. 8 , a C-channel-shaped reinforcing member  8  is installed inside the housing  4  along an upper end of the side surface part of the housing  4 . The reinforcing member  8  is also installed at each of upper ends of front and rear surface parts of the housing  4 , along the lengths of these upper ends. As with the first embodiment, the first bent part  9  and the second bent part  10  are formed at either end part of the reinforcing member  8 . 
         [0069]    Next, the reinforcing members  8  installed at the front and rear surface parts of the housing  4  are described with reference to  FIG. 9 . 
         [0070]      FIG. 9  is a front view of the reinforcing member of the railway vehicular power converter according to the second embodiment of the present invention. 
         [0071]    As shown in  FIG. 9 , the total length of each reinforcing member  8  is set at a length equivalent to those of the front and rear surface parts of the housing  4 . As a result, when attaching the reinforcing member  8  on the inner surfaces of the housing  4  as shown in  FIG. 8 , not only it is possible to install the reinforcing members  8  along the side surface part of the housing  4 , but also the reinforcing members  8  can be installed along the front and rear surface parts of the housing  4 . The sheet thickness of each reinforcing member  8  is substantially the same as that of the housing  4 . 
         [0072]    In this manner, in the railway vehicular power converter according to the second embodiment of the present invention, the reinforcing member  8  is provided inside the side surface part of the housing  4  where the securing plate  6  for securing the housing  4  to the railway vehicle body  2  is installed, and the reinforcing members  8  are also provided on the inside the securing plates located in the front and rear surface parts of the housing  4 . This leads to an increase in the area of reinforcement, further improving the strength of securing the housing  4  to the railway vehicle body  2 . 
         [0073]    Because each of the reinforcing members  8  is bent twice, the strength of securing the housing  4  to the railway vehicle body  2  can be further improved without increasing the sheet thicknesses of the housing  4  and the securing plates  6 . 
         [0074]    Accordingly, the strength of securing the housing  4  to the railway vehicle body  2  can be further improved, while reducing the size and weight of the housing  4 . 
         [0075]    Finally, a third embodiment of the present invention is described. The sections same as those of the first and second embodiments are simplified, and the sections different from those of the first and second embodiments are described in detail. 
         [0076]    The exterior of the housing  4  of the third embodiment is identical to those of the first and second embodiments. The internal structure of the housing  4  is different from those of the first and second embodiments and is therefore described with reference to  FIG. 10 . 
         [0077]      FIG. 10  is a cross-sectional view showing the rear surface side of the railway vehicular power converter according to the third embodiment of the present invention. 
         [0078]    As with the first embodiment, the C-channel-shaped reinforcing member  8  is installed inside the housing  4  along the upper end of the side surface part of the housing  4 . However, thin sheet plates each having a sheet thickness of equal to or less than half the sheet thickness of each of the housing  4 , securing plates  6 , and reinforcing member  8  of the first embodiment are used as the sheet plates of the housing  4 , securing plates  6 , and reinforcing member  8  of the third embodiment. The securing plates  6  and the reinforcing member  8  can be substantially the same in sheet thickness. The reinforcing member  8  is attached to the inner surface of the housing  4  by, for example, welding or rivets. 
         [0079]    In the railway vehicular power converter according to the third embodiment of the present invention, even though the thin sheet plates are used as the sheet plates of the housing  4  and the securing plates  6 , the use of the thin reinforcing member  8  on the inside of the housing  4  installed with the securing plates  6  can improve the strength of securing the housing  4  to the railway vehicle body  2 . 
         [0080]    Because the reinforcing member  8  is bent twice, the strength of securing the housing  4  to the railway vehicle body  2  can be improved, without causing the sheet thicknesses of the housing  4  and the securing plates  6  to be greater. 
         [0081]    Accordingly, the strength of securing the housing  4  to the railway vehicle body  2  can be improved, while reducing the size and weight of the housing  4 . 
         [0082]    Note that, in the first to third embodiments described above, the reinforcing member  8  is bent twice to form the first bent part  9  and the second bent part  10 . However, the number of bending is not limited to two: thus, the same effects can be achieved by bending the reinforcing member  8  once, three times or more often. 
         [0083]    When bending the reinforcing member  8  once, the strength of securing the housing  4  to the railway vehicle body  2  can be improved with such a simple bending operation. Bending the reinforcing member  8  three times or more often can further improve the strength of securing the housing  4  to the railway vehicle body  2 . 
         [0084]    In addition, the reinforcing member  8  is installed at the side surface part of the housing  4  in the first to third embodiments described above. However, the side surface part does not have to be the only place for installing the reinforcing member  8 . In other words, the reinforcing member  8  may not be installed at the side surface part of the housing  4  but at each of the front and rear surface parts or at only either one of the front or rear surface part. In such a case, the strength of securing the housing  4  to the railway vehicle body  2  can be improved with a simple installation operation of the reinforcing member  8 . 
         [0085]    Moreover, in the third embodiment the reinforcing member is installed at the side surface part of the housing  4 . However, the side surface part does not have to be the only place for installing the reinforcing member  8 . In other words, the reinforcing member  8  can be installed at each of the front and rear surface parts of the housing  4 . In this case, the strength of securing the housing  4  to the railway vehicle body  2  can be further improved. 
         [0086]    In the first to third embodiments described above, the securing plates  6  and the reinforcing member  8  are provided at the outer side surface  13 , the front surface  11 , and the rear surface  12  of the housing  4 . However, these are not necessarily the only places for installing the securing plates  6  and the reinforcing member  8 . In other words, the securing plates  6  and the reinforcing member  8  can be installed at the side surfaces facing the outer side surface  13  of the housing  4 . As a result, the strength of securing the housing  4  to the railway vehicle body  2  can be further improved. 
         [0087]    The housing  4  can be secured to the floor surface of the railway vehicle body  2  by installing the securing plates  6  and the reinforcing member  8  at only the outer side surface  13  of the housing  4  and the side surfaces facing the outer side surface  13  (in other words, the securing plates  6  and the reinforcing member  8  are not installed on the front surface  11  and the rear surface  12 ). 
         [0088]    Similarly, the housing  4  can be secured to the floor surface of the railway vehicle body  2  by installing the securing plates  6  and the reinforcing member  8  only to the outer front surface  11  and the rear surface  12  of the housing  4  (in other words, the securing plates  6  and the reinforcing member  8  are not installed on the outer side surface  13  or the opposing side surfaces). 
         [0089]    The disclosure of Japanese patent application No. 2011-228546 is incorporated herein as a reference.