Power Conversion Equipment

Abstract

To obtain a power conversion device that can suppress the deterioration of usability while suppressing an increase in manufacturing cost.SOLUTION: A power conversion device 100 includes a box-shaped housing and a front panel 120 provided on the front side of the housing and having an opening 121 communicating with the inner space of the housing. The power conversion device includes a transparent waterproof cover 70 that is arranged on the front panel 120 so as to close the opening 121, and prevents water from entering the inner space of the housing from the opening 121, and an operation panel 50 including a display unit 51 and an operation unit 52 that are provided in the inner space of the housing at a position facing through an opening 121 from the front side of the waterproof cover 70.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a power conversion device. [Background technology]

[0002] The power conversion device includes a main circuit section including a semiconductor module, a heat dissipation mechanism for the main circuit section, and a control circuit section for controlling the main circuit section, and can change the operating conditions of the load by controlling the switching operation of the semiconductor module. A general-purpose power conversion device that can change the operating conditions to suit the application of the load is provided with an operation panel. The operation panel is a user interface for setting the operating conditions, etc. The operation panel disclosed in Patent Document 1 is provided on the front cover (lid) of the housing (unit case) of the power conversion device (drive control device). Patent Document 1 describes that the unit case is waterproof. Note that Patent Document 1 does not describe that the operation panel itself has a waterproof function, but since a part of the operation panel is provided to protrude outside the unit case, it can be easily imagined that the operation panel itself is also waterproof. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-176074 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, this type of operation panel in the prior art is designed on the assumption that it will be installed in a waterproof power conversion device. Therefore, it is necessary to make the operation panel itself waterproof. For example, since many general-purpose power conversion devices are non-waterproof, in order to convert the operation panel installed in the power conversion device to a special power conversion device that meets, for example, waterproof performance of IP55 class or higher, it is necessary to make a significant change in the specifications of the operation panel itself. In addition, an operation panel with waterproof performance of IP55 class or higher will be an excessive specification when used in a general-purpose power conversion device, and there is a risk that the manufacturing cost of the general-purpose power conversion device will increase significantly, thereby reducing the price competitiveness. In addition, when an operation panel used in a general-purpose power conversion device is improved to a waterproof specification, there may be cases where the specifications of the operation keys and the like installed on the operation panel are changed due to design constraints. Therefore, for users who are familiar with the operation panel of a general-purpose power conversion device, there is a risk that it will become difficult to use, which is not preferable.

[0005] The present invention has been made in view of the above, and has an object to provide a power conversion device that can suppress deterioration in usability while suppressing an increase in manufacturing costs. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, a power conversion device according to the present invention includes a box-shaped housing having a front opening on a front side thereof, and a cover provided on the front side of the housing to cover the front opening. jointly a front panel having an opening, a transparent waterproof cover disposed on the front panel so as to cover the opening and preventing water from entering the interior space of the housing through the opening, and an operation panel having a display unit and an operation unit disposed on the rear side of the waterproof cover and disposed in the interior space of the housing at a position visible from the front side of the waterproof cover through the opening, a frame into which the waterproof cover is fitted and into which the operation panel is disposed; wherein each of the housing and the front panel is a waterproof structure. The frame is fixed to the front panel at a position where the operation panel can be seen from the front side of the waterproof cover through the opening. . Effect of the Invention

[0007] The present invention has the advantage that it is possible to suppress a decrease in usability while suppressing an increase in manufacturing costs. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is an external view of a power conversion device 100 according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing an example of a circuit constituting the power conversion device 100 shown in FIG. [Diagram 3] FIG. 2 is a diagram showing an internal structure of the power conversion device 100 shown in FIG. [Figure 4] FIG. 1 is a diagram showing the structure of the front panel 120, the waterproof cover 70, and the operation panel 50. [Diagram 5] FIG. 13 is a diagram showing a waterproof structure of a front panel 120, an operation panel 50, and the like provided in a power conversion device 100 according to a second embodiment of the present invention. [Figure 6] FIG. 11 is a diagram showing a waterproof structure of a front panel 120, an operation panel 50, and the like provided in a power conversion device 100 according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a power conversion device according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiment. Note that in each embodiment, deviations in directions such as parallel, right angle, horizontal, vertical, up and down, left and right, etc., are allowed to a degree that does not impair the effects of the present invention. In addition, the X-axis direction, the Y-axis direction, and the Z-axis direction respectively represent directions parallel to the X-axis, the Y-axis direction, and the Z-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are perpendicular to each other. The XY plane, the YZ plane, and the ZX plane respectively represent imaginary planes parallel to the X-axis direction and the Y-axis direction, imaginary planes parallel to the Y-axis direction and the Z-axis direction, and imaginary planes parallel to the Z-axis direction and the X-axis direction. In FIG. 1 and subsequent figures, the direction indicated by the arrow in the X-axis direction is the positive X-axis direction, and the direction opposite to the direction is the negative X-axis direction. The direction indicated by the arrow in the Y-axis direction is the positive Y-axis direction, and the direction opposite to the direction is the negative Y-axis direction. The direction indicated by the arrow in the Z-axis direction is the positive Z-axis direction, and the direction opposite to the direction is the negative Z-axis direction.

[0010] First embodiment 1 is an external view of a power conversion device 100 according to a first embodiment of the present invention. The power conversion device 100 is an inverter having a housing 110 with a sealed structure that prevents the intrusion of, for example, rain, dust, and the like. The up-down direction of the housing 110 is equal to the X-axis direction, the left-right direction of the housing 110 is equal to the Y-axis direction, and the depth direction of the housing 110 is equal to the Z-axis direction. The housing 110 is a box-shaped storage body. A front panel 120 is provided on the positive Z-axis direction side of the housing 110.

[0011] The front panel 120 is provided on the front side (positive Z-axis direction side) of the housing 110, and is a blocking member that covers the opening of the housing 110. The front panel 120 is provided to the housing 110 so as to be openable and closable via a hinge 130 fixed to a side surface of the housing 110. The front panel 120 is provided with an opening communicating with the inner space of the housing 110, and a transparent waterproof cover 70 that is disposed on the front panel 120 so as to close the opening and prevents water from entering the inner space of the housing 110 from the opening. The operation panel 50 is provided in the inner space of the housing 110 at a position that can be seen from the front side of the waterproof cover 70 through the opening. Details of the waterproof cover 70 and the operation panel 50 will be described later.

[0012] The power conversion device 100 is not limited to a so-called inverter (a device that converts DC to AC with a variable voltage and variable frequency), but may be any device that includes various reactors described below and a switching element for power conversion. Therefore, the power conversion device 100 may be, for example, a converter that converts DC power to AC power, a DC chopper that controls the value of DC power by switching (on / off) the DC power with a power semiconductor element, or a cycloconverter that obtains AC at a frequency lower than the input frequency.

[0013] Fig. 2 is a diagram showing an example of a circuit constituting the power conversion device 100 shown in Fig. 1. For example, the power conversion device 100 includes an EMC (Electromagnetic Compatibility) filter 101, a diode rectifier 102 that rectifies a three-phase AC voltage, and a three-phase inverter main circuit 103.

[0014] The EMC filter 101 is composed of a line capacitor 1 and a common mode choke coil 2 (L c ), a ground capacitor 3, etc.

[0015] The three-phase inverter main circuit 103 is a core 4 (L core ), DC reactor 5(L DC ), a smoothing capacitor 7, and a plurality of switching elements S 1 ~S 6The three-phase inverter main circuit 103 converts the rectified voltage into a three-phase AC voltage. The three-phase AC voltage converted by the three-phase inverter main circuit 103 is applied to a load (such as a motor 200).

[0016] The core 4 is provided on the positive and negative DC buses that connect the diode rectifier 102 and the three-phase inverter main circuit 103, and performs auxiliary suppression of electromagnetic noise.

[0017] The DC reactor 5 is provided, for example, on the positive DC bus in order to suppress harmonic currents superimposed on the commercial voltage and to improve the power factor.

[0018] Multiple switching elements S 1 ~S 6 are three-phase bridge-connected semiconductor switching elements that convert the DC power supplied from the diode rectifier 102 into AC power. 1 ~S 6 When there is no need to distinguish between them, they are referred to as "switching elements." Switching elements include MOSFETs (Metal Oxide Semiconductor Field Effect Transistors) and IGBTs (Insulated Gate Bipolar Transistors). Each switching element is turned on or off according to a PWM signal (gate drive signal) input from a gate drive circuit (not shown). The gate drive circuit is a circuit that converts a PWM signal input from a control circuit (not shown) into a gate drive signal, which is a signal with a voltage value capable of driving the switching element, and inputs the gate drive signal to the switching element.

[0019] The common mode choke coil 2, core 4, and DC reactor 5 are each formed by winding a wire around a core portion formed by stacking annular members punched out from multiple silicon steel plates, a core portion formed by sintering ferrite, etc. When a current is applied to the switching element, the switching element, common mode choke coil 2, core 4, DC reactor 5, etc. generate heat.

[0020] Heat generated by heat generating components such as the common mode choke coil 2, the core 4, and the DC reactor 5 may be transferred to surrounding components, causing the temperature of the surrounding components to exceed the allowable temperature. The surrounding components include, for example, the line capacitor 1, the grounding capacitor 3, and the smoothing capacitor 7 (C dc ), and rectifying elements constituting the diode rectifier 102. The power conversion device 100 includes a heat shield, which is a metal member, to prevent heat generated in the heat-generating components from being transferred to surrounding components. The structure of the heat shield will be described with reference to FIG. 3 etc.

[0021] Fig. 3 is a diagram showing the internal structure of the power conversion device 100 shown in Fig. 1. As shown in Fig. 3, a DC reactor 5, a heat shield 10, a common mode choke coil 2, a control board 8, etc. are provided inside a housing 110 that forms the outer shell of the power conversion device 100. A switching element is provided on an end face (not shown) of the control board 8 in the negative Z-axis direction.

[0022] In the power converter 100, a heat shield 10 is installed so as to surround the DC reactor 5. The heat shield 10 is fixed, for example, to an end surface in the positive Z-axis direction of the heat dissipation fin base 6. The heat dissipation fin base 6 is a plate-shaped heat dissipation member for dissipating heat generated in internal components of the housing 110 to the outside of the housing 110. Examples of materials for the heat dissipation fin base 6 include metals such as aluminum, austenitic stainless steel alloy, copper alloy, cast iron, steel, and iron alloy. Note that a plurality of fins (not shown) are provided on an end surface in the negative Z-axis direction of the heat dissipation fin base 6. By installing the heat shield 10 around the DC reactor 5, the heat generated in the DC reactor 5 is less likely to be transmitted to the surrounding components.

[0023] Furthermore, in the power conversion device 100, some of the heat-generating components (such as the core 4) are fixed to the heat shield 10. The heat shield 10 can be made of copper, aluminum, chromium, molybdenum, nickel, iron, titanium, palladium, indium, tungsten, gold, platinum, silver, stainless steel (SUS), or an alloy containing a plurality of these, such as an alloy of nickel and iron. Since the heat shield 10 is fixed to the heat dissipation fin base 6, some of the heat generated by the heat-generating components is transferred to the heat shield 10 and then to the heat dissipation fin base 6, etc. This further reduces the impact of heat on the components disposed around the heat-generating components.

[0024] 4, the structures of the waterproof cover 70 and the operation panel 50 and the method of fixing them to the front panel 120 will be described.

[0025] An opening 121 is formed in the front panel 120. A wall surface 122 forming the opening 121 is rectangular when the front panel 120 is viewed in a plane in the Z-axis direction. The size of the opening 121 is set to a dimension that allows at least the display unit 51 and the operation unit 52 of the operation panel 50 to be viewed from the front side of the waterproof cover 70 through the opening 121. The position of the opening 121 is set according to the position of the operation panel 50, and may be near the center of the front panel 120 or near the periphery of the front panel 120. The periphery of the front panel 120 is the end face in the X-axis direction and the end face in the Y-axis direction of the front panel 120. The size and shape of the opening 121 may be any size that allows the display unit 51 and the operation unit 52 of the operation panel 50 to be viewed from the front side of the waterproof cover 70 through the opening 121, and is not limited to the illustrated example. The position of the opening 121 in the entire area of ​​the front panel 120 is also not limited to the illustrated example.

[0026] The waterproof cover 70 is fixed to the back side (negative Z-axis direction side) of the front panel 120. Specifically, for example, a screw 71 is inserted into a screw hole provided in the waterproof cover 70, and a tip portion (male thread portion) of the screw 71 is screwed into the waterproof cover 70, thereby fixing the waterproof cover 70 to the front panel 120. By using the screw 71, the waterproof cover 70 can be easily fixed to the front panel 120 even when the manufacturing of the power conversion device 100 is automated. Furthermore, even when the waterproof cover 70 needs to be replaced because the surface is scratched, the waterproof cover 70 can be easily removed by simply removing the screw 71.

[0027] The method of fixing the waterproof cover 70 is not limited to screw fastening, and the waterproof cover 70 may be fixed to the front panel 120 by adhesion using, for example, an adhesive. Also, in order to improve the waterproof performance of the contact surface between the waterproof cover 70 and the front panel 120, a rectangular frame may be placed on the back side of the waterproof cover 70, and the waterproof cover 70 may be sandwiched between this frame and the front panel 120, and the frame may be fixed to the front panel 120 using a fastening member such as a screw.

[0028] Furthermore, the position of the waterproof cover 70 is not limited to the rear side of the front panel 120, but may be on the front side of the front panel 120. In this case as well, the waterproof cover 70 may be screwed to the front panel 120 with a fastening member, or a rectangular frame may be disposed on the front side of the waterproof cover 70 and fixed so as to sandwich the waterproof cover 70 in the same manner as described above.

[0029] The dimensions of the waterproof cover 70 are set to a size capable of closing the opening 121 formed in the front panel 120. That is, the area of ​​the waterproof cover 70 in plan view in the Z-axis direction is larger than the area of ​​the opening 121, and the dimensions in the X-axis and Y-axis directions of the waterproof cover 70 in plan view in the Z-axis direction are larger than the dimensions in the X-axis and Y-axis directions of the wall surface 122 that forms the opening 121.

[0030] The waterproof cover 70 desirably has excellent visibility that allows the user to easily check the information displayed on the display unit 51 of the operation panel 50, flexibility that allows the user to easily operate the operation unit 52 of the operation panel 50, and durability that can withstand deformation and damage caused by user operations and flying objects outside the power conversion device 100. Examples of materials that combine these visibility, flexibility, and durability include translucent resins such as acrylic resins, polycarbonate resins, polyethylene terephthalate resins, and polyethylene resins. Note that the waterproof cover 70 is preferably colorless and transparent, but as long as the display contents and operation keys of the operation panel 50 can be visually observed from the front side of the front panel 120, there is no prohibition on the waterproof cover 70 being colored and transparent.

[0031] The operation panel 50 is fixed, for example, via a fixing member 53 to a surface in the positive Z-axis direction of the control board 8 shown in FIG. 3. The fixing member 53 may be, for example, a plate-shaped member made of insulating resin, or may be an insulating columnar member provided at the four corners of the operation panel 50. At this time, the operation panel 50 is arranged so that the display surface of the display unit 51 and the operation surface of the operation unit 52 face the waterproof cover 70. In this way, the operation panel 50 is fixed to a component provided inside the housing 110 rather than to the waterproof cover 70, and thus the waterproof cover 70 can be easily attached and replaced.

[0032] Note that the method of fixing the operation panel 50 is not limited to this, and for example, the operation panel 50 may be screwed to the back side of the front panel 120 so as to sandwich the waterproof cover 70. By providing the operation panel 50 in this manner, even if the specifications of the circuit components (including the control board 8) provided in the housing 110 are changed, the operation panel 50 can be fixed at a position where it can be viewed and operated through the waterproof cover 70, regardless of the location of the control board 8, etc.

[0033] The display unit 51 of the operation panel 50 is an LCD (Liquid Crystal Display), an organic EL (Electroluminescence) display, or the like, which displays information set by the operation unit 52, operation state information of the power conversion device 100, etc. The operation unit 52 of the operation panel 50 is a user interface for inputting information required for operation settings of the power conversion device 100, etc., and is a numeric keypad, operation buttons, etc.

[0034] The housing 110 and the front panel 120 of the power conversion device 100 thus configured have a structure that satisfies waterproof performance such as IP55 class. Therefore, it is necessary to prevent water from entering the inside of the housing 110 from the contact surface between the front panel 120 and the operation panel 50. It is also necessary to ensure that the operation panel 50 itself is waterproof. In order to take such measures, for example, if a non-waterproof operation panel (operation panel 50) used in a general-purpose power conversion device is improved to have a waterproof function, it is necessary to significantly improve the operation panel 50 itself. In addition, a special operation panel (operation panel not shown) having a waterproof performance of IP55 class or higher is an excessive specification for use in a general-purpose power conversion device, and this may lead to a significant increase in the manufacturing cost of the power conversion device 100. The increase in the manufacturing cost of the power conversion device 100 leads to a decrease in the price competitiveness of the product. In addition, when the operation panel 50 used in a general-purpose power conversion device is improved to have a waterproof specification, the operation unit 52 and the like may be changed due to design constraints. Therefore, for users who are familiar with the operation panel 50 of a general-purpose power converter, there is a risk that the operation panel 50 may become difficult to use, which is not preferable.

[0035] The power conversion device 100 according to this embodiment includes a box-shaped housing 110, and a front panel 120 that is provided on the front side of the housing 110 and has an opening 121 that communicates with the inner space of the housing 110. The power conversion device 100 also includes a transparent waterproof cover 70 that is disposed on the front panel 120 so as to cover the opening 121 and prevents water from entering the inner space of the housing 110 through the opening 121, and an operation panel 50 that is provided in the inner space of the housing 110 at a position that can be seen from the front side of the waterproof cover 70 through the opening 121.

[0036] With this configuration, the waterproof cover 70 provided on the front panel 120 prevents water from entering the inner space of the housing 110, and by covering the operation panel 50, waterproofing measures for the operation panel 50 are not necessary. Therefore, a general-purpose operation panel 50 without a special waterproof function can be used, and an increase in the manufacturing cost of the operation panel 50 can be suppressed. In addition, usability for users who are familiar with the operation panel 50 used in the general-purpose power conversion device 100 is not deteriorated.

[0037] Furthermore, with the power conversion device 100 according to this embodiment, only the non-waterproof operation panel 50 can be used, eliminating the need to manufacture waterproof and non-waterproof panels in parallel. This allows for mass production of operation panels 50 of a single specification, further reducing the cost of the operation panel 50 and suppressing deterioration in quality.

[0038] Embodiment 2 5 is a diagram showing the waterproof structure of a front panel 120, an operation panel 50, and the like included in a power conversion device 100 according to a second embodiment of the present invention. In the following, the same parts as those in the first embodiment are given the same reference numerals, and their explanation is omitted, and only different parts will be described.

[0039] The front panel 120 of the power conversion device 100 in embodiment 2 includes an assembly 90, an operation panel 50 provided on the negative Z-axis direction side of the assembly 90, and a bottom plate 82 provided on the negative Z-axis direction side of the assembly 90 so as to cover the operation panel 50.

[0040] The assembly 90 is a layered structure that is assembled by layering the waterproof gasket 80, the waterproof cover 70A, the frame 81, and the operation panel 50 in this order in the Z-axis direction.

[0041] The waterproof gasket 80 is a rectangular annular member with an opening 80a formed on the inside. The waterproof gasket 80 is, for example, rubber with a concave or convex cross section. The size of the waterproof gasket 80 is set to the same dimensions as the waterproof cover 70A when the waterproof cover 70A is viewed in a plan view in the Z-axis direction. The size of the waterproof gasket 80 is set to a dimension that can be fitted into the step portion 81a of the frame body 81 and is wider than the opening 81b on the inside of the frame body 81. The waterproof gasket 80 is sandwiched between the waterproof cover 70A and the front panel 120.

[0042] The waterproof cover 70A is made of a translucent resin that has visibility, flexibility, and durability, similar to the waterproof cover 70 of the first embodiment. The size of the waterproof cover 70A is set so that it can be fitted into the step portion 81a of the frame body 81 and is wider than the opening 81b inside the frame body 81. The waterproof cover 70A is sandwiched between the waterproof gasket 80 and the frame body 81 without using the screw 71 shown in FIG.

[0043] The frame 81 is a rectangular annular member with an opening 81b formed on the inside, and has a cross-sectional shape that is recessed toward the negative Z-axis direction, for example. A step 81a is provided on the inside of the frame 81. Due to the step 81a, the area of ​​the opening 81b when viewed in a plan view from the Z-axis direction becomes gradually smaller as it progresses in the negative Z-axis direction. The step 81a is a boundary portion between the wall surface surrounding the waterproof cover 70A and the waterproof gasket 80 and the wall surface surrounding the operation panel 50, among the inner walls of the frame 81.

[0044] The waterproof cover 70A and the waterproof gasket 80 are arranged so as to be stacked on the step portion 81a of the frame body 81. That is, the waterproof cover 70A is placed on the step portion 81a of the frame body 81 so as to close the opening 81b, and the waterproof gasket 80 is placed on the upper side (front side) of the waterproof cover 70A. In this way, an assembly 90 is obtained.

[0045] When assembling the assembly 90, the contact surfaces of the waterproof cover 70A and the frame 81, and the contact surfaces of the waterproof gasket 80 and the waterproof cover 70A are cleaned with alcohol or the like. By removing foreign matter through cleaning, the waterproof effect can be improved.

[0046] The operation panel 50 is placed in the opening 81b of the assembled body 90 thus assembled. As a result, the operation panel 50 comes into contact with the waterproof cover 70A.

[0047] Then, the bottom plate 82 is installed so as to cover the negative Z-axis direction side of the operation panel 50. The screw 72 is inserted into the screw hole of the bottom plate 82, and the screw 72 is inserted into the screw hole of the frame body 81. Finally, the tip portion (male thread portion) of the screw 72 is screwed into the front panel 120.

[0048] As a result, the operation panel 50 is fixed to the front panel 120 in a state where it is sandwiched between the assembly 90 and the bottom plate 82. In addition, the opening 121 of the front panel 120 is closed from the rear side of the front panel 120 by the waterproof gasket 80 and the waterproof cover 70A.

[0049] At this time, the operation panel 50 is positioned so as to be visible from the front side of the front panel 120 via the opening 121 of the front panel 120 , the opening 80 a of the waterproof gasket 80 , the waterproof cover 70 A, and the opening 81 b of the frame body 81 .

[0050] As described above, the power conversion device 100 according to the second embodiment includes the frame 81 into which the waterproof cover 70A is fitted and into which the operation panel 50 is disposed. The frame 81 is fixed to the front panel 120 at a position where the operation panel 50 can be seen through the opening 121 from the front side of the waterproof cover 70A.

[0051] With this configuration, the operation panel 50 arranged inside the frame body 81 is fixed to the front panel 120 in a state of contact with the waterproof cover 70A. Therefore, work such as fine-tuning the position of the operation panel 50 in the XY axis direction, for example, in order to arrange the operation panel 50 near the center of the opening 121 of the front panel 120 is not required. That is, the operation panel 50 can be assembled to the front panel 120 with high precision without adjustment for positioning the operation panel 50. Furthermore, the operation panel 50 can be assembled to the waterproof cover 70A with high precision.

[0052] In addition, since the operation panel 50 can be assembled with high precision, even if the waterproof cover 70A is processed to have projections and recesses corresponding to the shape of the operation unit 52 (such as a numeric keypad) in order to improve the operability of the operation panel 50, the operation unit 52 can be easily fitted into the projections and recesses. Therefore, the power conversion device 100 can be easily assembled, while improving the ease of use of the operation panel 50 for the user.

[0053] Furthermore, by having the frame 81 sandwich the waterproof gasket 80 together with the front panel 120, the assembly of the waterproof gasket 80, waterproof cover 70A, etc. is facilitated compared to a structure in which, for example, a waterproof structure is provided on the front panel 120 and then the frame 81, etc. are fixed to the front panel 120. Furthermore, by having the waterproof gasket 80 sandwiched in place, the waterproof gasket 80 is crushed, so that the contact pressure of the waterproof gasket 80 with the front panel 120 can be made uniform, and a robust waterproof structure can be obtained even with a high level of waterproofing.

[0054] Third embodiment 6 is a diagram showing the waterproof structure of a front panel 120, an operation panel 50, and the like included in a power conversion device 100 according to a third embodiment of the present invention. In the following, the same parts as those in the second embodiment are given the same reference numerals, and their explanation is omitted, and only the different parts will be described.

[0055] The power converter 100 according to the third embodiment includes, in addition to the configuration of the second embodiment, a waterproof cover pressing member 30 fixed to the front panel 120. The waterproof cover pressing member 30 is a rectangular annular member with an opening 30a formed on the inside. The waterproof cover pressing member 30 is a member that presses the entire vicinity of the periphery of the waterproof cover 70A within the surface of the waterproof cover 70A in the positive Z-axis direction. Pressing the entire vicinity of the periphery of the waterproof cover 70A prevents the waterproof cover 70A from floating up. In addition, pressing the entire vicinity of the periphery of the waterproof cover 70A sandwiches the waterproof cover 70A between the waterproof cover pressing member 30 and the frame 81, improving the degree of sealing of the contact portion between the waterproof cover 70A and the frame 81, thereby improving the waterproof performance.

[0056] The waterproof cover pressing member 30 includes an annular frame portion 31 and two flange portions 32. The waterproof cover pressing member 30 may be manufactured, for example, by pressing a plate-shaped metal part so that the frame portion 31 and the flange portion 32 are integrally manufactured, or may be manufactured by connecting the frame portion 31 and the flange portion 32 that are manufactured separately to each other by welding or the like.

[0057] A step portion 31a is provided on the inside of the frame portion 31. The step portion 31a forms a surface at the end of the frame portion 31 in the negative Z-axis direction that presses against the waterproof cover 70A.

[0058] The flange 32 is a portion that extends on the side opposite to the inside of the frame body 81. A screw hole is formed in the flange 32 for fixing the entire frame body 81 to the front panel 120. A screw 73 is inserted into this screw hole, and the tip portion (male thread portion) of the screw 73 is screwed into the front panel 120, whereby the waterproof cover holding member 30 is fixed to the front panel 120.

[0059] The provision of the waterproof cover retainer 30 provides the following effects.

[0060] When a soft film-like waterproof cover 70 is applied to the power conversion device 100 having a totally enclosed structure with excellent waterproofing, when the temperature inside the housing 110 increases due to heat from the circuit components, the air pressure difference between the inside and outside of the housing 110 increases. This can cause the waterproof cover 70A to deform as if it is being pushed (expanded) from the inside of the housing 110 toward the outside. When the waterproof cover 70A deforms in this way, the gap between the operation panel 50 and the waterproof cover 70A increases, making it difficult to operate the operation panel 50.

[0061] According to the power conversion device 100 of the third embodiment, by providing the waterproof cover pressing member 30, even if a pressure difference occurs between the inside and outside of the housing 110, the waterproof cover 70A is prevented from floating up. Therefore, even in the power conversion device 100 having a totally closed structure, it is possible to prevent the operability of the operation panel 50 from being deteriorated.

[0062] In addition, the waterproof cover holding member 30, together with the frame body 81, is fixed to the front panel 120 while sandwiching the portion of the waterproof cover 70A near the peripheral edge thereof, thereby preventing the waterproof cover 70A from floating up and further improving the waterproof performance.

[0063] The configurations shown in the above embodiments are examples of the contents of the present invention, and may be combined with other known technologies. Parts of the configurations may be omitted or modified without departing from the gist of the present invention. [Explanation of symbols]

[0064] 1: Line capacitor 2: Common mode choke coil 3: Ground capacitor 4: Core 5: DC reactor 6: Heat dissipation fin base 7: Smoothing capacitor 8: Control board 10: Heat shield 12: Hole 30: Waterproof cover retainer 30a: opening 31: Frame 31a: Step 32: Flange 50: Operation panel 51: Display section 52: Operation section 53: Fixing member 70: Waterproof cover 70A: Waterproof cover 71: Screw 72: Screw 73: Screw 80: Waterproof gasket 80a: opening 81: Frame 81a: Step 81b: Opening 82: Bottom plate 90: Assembly 100: Power conversion device 101: EMC filter 102: Diode rectifier 103: Three-phase inverter main circuit 110: Housing 120: Front panel 121: Opening 122: Wall 130: Hinge 200: Motor

Claims

1. A box-shaped housing having a front opening on a front side; a front panel provided on a front side of the housing to cover the front side opening and having an opening; a transparent waterproof cover disposed on the front panel to cover the opening and prevent water from entering an inner space of the housing through the opening; an operation panel provided in the inner space of the housing at a position accessible from the front side of the waterproof cover through the opening, the operation panel having a display unit and an operation unit provided on the rear side of the waterproof cover; a frame into which the waterproof cover is fitted and into which the operation panel is disposed; Equipped with Each of the housing and the front panel is a waterproof structure, the frame is fixed to the front panel at a position where the operation panel can be seen from the front side of the waterproof cover through the opening; Power conversion equipment.

2. The power conversion device according to claim 1 , further comprising a waterproof cover pressing member provided on the front side of the waterproof cover and fixed to the front panel in a state where the waterproof cover is sandwiched near the peripheral edge portion together with the frame body.

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