Motor control device

Abstract

Provided is a motor control device provided with a filter cover part with a simple configuration while suppressing an increase in the number of components and assembly steps.　A motor control device 1 comprises: a printed circuit board 20; a terminal connection member 80 having an element connection part 81 connected to switching elements 22 and a terminal part 82 to which external wiring is detachably connected; and a case 10. The case 10 comprises: a base member 11; a main cover 12 which covers a part provided with the printed circuit board 20 and is attached to the base member 11 in a state in which a terminal part 82 is projected in a first direction X; a filter 128 which is provided so as to cover a communication hole 125 formed in the main cover 12; and a sub cover 13 which is detachably provided to the base member 11 so as to cover the terminal part 82. The sub cover 13 integrally has a filter cover part 138 provided so as to cover the filter 128.

Description

Motor control device

[0001] The present invention relates to a motor control device.

[0002] Cases for housing electronic devices such as circuit boards are sometimes provided with ventilation holes (breathing holes) that connect the inside and outside of the case to prevent fluctuations in internal pressure due to temperature changes. In such cases, a filter is provided in the ventilation holes to prevent rainwater and foreign objects from entering the case from the outside.

[0003] Patent Document 1 discloses a waterproof case having a bottom plate on which an electronic device is mounted and a top lid that covers the bottom plate. The waterproof case is equipped with a breathing hole that penetrates the top lid, a filter that covers the breathing hole, and a filter cover that is formed on the outer surface of the top lid and covers the filter.

[0004] Japanese Patent Application Laid-Open No. 2006-5162

[0005] However, as disclosed in Patent Document 1, when a filter cover that covers a filter is provided on a top lid having a communication hole, forming the filter cover integrally with the top lid results in a complex structure of the top lid. On the other hand, attempting to detachably attach the filter cover to the top lid increases the number of parts and assembly steps. The present invention aims to provide a motor control device that includes a filter cover with a simple configuration while minimizing the increase in the number of parts and assembly steps.

[0006] In order to solve the above problem, in a first aspect of the present invention, a motor control device comprises a substrate on which switching elements that drive a motor are mounted, a terminal connection member having an element connection portion connected to the switching element and a terminal portion to which external wiring is detachably connected, and extending in a first direction along a main surface of the substrate, and a case that houses the switching elements, the substrate, and the terminal connection member, wherein the case comprises a base member having a first surface to which the substrate is fixed, a main cover that covers at least the portion of the first surface of the base member on which the substrate is provided and is attached to the base member with the terminal portion protruding in the first direction, an air-permeable filter that is arranged to cover a communication hole formed in the main cover that connects the inside and outside of the case, and a sub-cover that is detachably attached to the base member to cover the terminal portion, and the sub-cover has an integral filter cover portion that is arranged to cover the filter.

[0007] With this configuration, the filter cover portion is provided to cover the filter, preventing external forces such as high-pressure water and flying stones from acting on the filter. This prevents water and dust from entering the case and allows gas to flow in and out due to pressure changes within the case without using a special filter designed to protect against such external forces. Furthermore, since the sub-cover has the filter cover portion integrated into it, the filter cover portion that covers the filter can be set simply by attaching the main cover and sub-cover to the base member. This makes it possible to provide a motor control device with a filter cover portion that has a simple configuration while minimizing increases in the number of parts and assembly steps.

[0008] A second aspect of the present invention is a motor control device according to the first aspect, wherein the main cover has an outer surface facing a first side in the thickness direction of the substrate and a bottom wall into which the communication hole opens, and a recess in the outer surface that opens to the first side in the thickness direction, and the filter is preferably arranged within the recess so as to cover the communication hole, and the filter cover portion is preferably arranged within the recess so as to face the bottom wall in the thickness direction across the filter.

[0009] With this configuration, the filter and the filter cover are provided in the recess formed in the main cover, so the filter cover that covers the filter can be provided with a simple configuration. Also, by providing the filter cover in the recess, the motor control device can be made compact in the thickness direction.

[0010] A third aspect of the present invention is a motor control device according to the first or second aspect, wherein the filter cover portion is spaced apart from the filter on a first side in the plate thickness direction, and when viewed from the plate thickness direction, a gap is formed between the filter cover portion and the recess.

[0011] With this configuration, the filter cover portion is spaced apart from the filter on the first side in the thickness direction, so that with a simple configuration, good ventilation is achieved between the inside and outside of the main cover through the filter, while the filter cover portion effectively prevents rainwater and foreign matter from the outside from reaching the filter.

[0012] According to one aspect of the present invention, it is possible to provide a motor control device that has a filter cover portion with a simple configuration while suppressing an increase in the number of parts and assembly steps.

[0013] 1 is a perspective view showing a motor control device according to an embodiment of the present invention. FIG. 1 is a perspective view of the motor control device of FIG. 1, viewed from a direction different from that of FIG. 1. FIG. 2 is a perspective view showing the motor control device of FIG. 1 with the main cover and sub-cover removed. FIG. 3 is a cross-sectional view of the motor control device of FIG. 1. FIG. 4 is a plan view of the motor control device of FIG. 1. FIG. 5 is a perspective view showing the motor control device of FIG. 1 with the sub-cover removed. FIG. 6 is an enlarged cross-sectional view showing the contact portion between the main cover and the sub-cover. FIG. 7 is a cross-sectional view taken along the line II in FIG. 4. FIG. 8 is an enlarged cross-sectional view showing the filter and filter cover portion of the motor control device.

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A motor control device according to an embodiment of the present invention will be described below with reference to the accompanying drawings. However, the present invention is not limited to this embodiment.

[0015] <Motor Control Device 1> FIG. 1 is a perspective view of the motor control device 1 according to an embodiment. FIG. 2 is a perspective view of the motor control device 1 of FIG. 1, viewed from a different direction than that of FIG. 1. FIG. 3 is a perspective view showing the motor control device 1 of FIG. 1 with the main cover 12 and sub-cover 13 removed. FIG. 4 is a cross-sectional view of the motor control device of FIG. 1. The motor control device 1 shown in FIGS. 1 to 4 has an inverter function that converts DC power supplied from a battery (not shown) into AC power and drives an AC motor (not shown) with the converted AC power. The motor control device 1 according to this embodiment is mounted on a vehicle such as a motorcycle, a moped, or an automobile. The motor control device 1 includes a case 10. As shown in FIGS. 3 and 4, the motor control device 1 includes a printed circuit board (board) 20, multiple electrolytic capacitors 60, and multiple terminal connection members 80 within the case 10.

[0016] As shown in Figures 1, 2, and 4, the case 10 mainly comprises a base member 11, a main cover 12, and a sub-cover 13. As shown in Figures 3 and 4, the base member 11 is formed in a box shape with one side open. The printed circuit board 20, a plurality of electrolytic capacitors 60, and a plurality of terminal connection members 80 are mounted on the base member 11.

[0017] <Printed circuit board 20> The printed circuit board 20 is plate-shaped, and has a plurality of switching elements 22 mounted on its surface (main surface) 20a. The printed circuit board 20 is formed in a rectangular shape when viewed in a thickness direction Z of the printed circuit board 20 that is perpendicular to the surface 20a. The printed circuit board 20 is fixed to a first surface 11f of the base member 11. In the following description, a direction perpendicular to the thickness direction Z and along the surface 20a of the printed circuit board 20 is referred to as a first direction X, and a direction perpendicular to the thickness direction Z and the first direction X is referred to as a second direction Y.

[0018] The printed circuit board 20 is a PWB (Printed Wiring Board). The ON / OFF operations of the multiple switching elements 22 are controlled by a switching control circuit (not shown), thereby operating the motor control device 1 under optimal conditions according to the driving state of the AC motor.

[0019] A plurality of first pattern terminals (not shown) and a plurality of second pattern terminals (not shown) are provided on the surface 20a of the printed circuit board 20 on one side X1 in the first direction X with respect to the plurality of switching elements 22. The first pattern terminals are electrically connected to the positive electrodes of the switching elements 22, for example, via a wiring pattern (not shown) formed on the printed circuit board 20. The second pattern terminals are electrically connected to the negative electrodes of the switching elements 22, for example, via a wiring pattern (not shown) formed on the printed circuit board 20.

[0020] The printed circuit board 20 is provided with a bus bar 30 on one side X1 in the first direction X of the multiple switching elements 22. The bus bar 30 is connected to the multiple first pattern terminals and the multiple second pattern terminals of the printed circuit board 20. The bus bar 30 is mounted on the front surface 20a of the printed circuit board 20 by being connected to the multiple first pattern terminals and the multiple second pattern terminals. The bus bar 30 electrically connects the multiple electrolytic capacitors 60 and the multiple switching elements 22.

[0021] The bus bar 30 includes a first bus bar 31 and a second bus bar 32. Each of the first bus bar 31 and the second bus bar 32 has a plate shape extending in the second direction Y and is made of a conductive material. The first bus bar 31 is electrically connected to the positive electrode of the switching element 22 via a first pattern terminal and a wiring pattern (not shown). The second bus bar 32 is electrically connected to the negative electrode of the switching element 22 via a second pattern terminal and a wiring pattern (not shown).

[0022] <Electrolytic Capacitors 60> The plurality of electrolytic capacitors 60 are arranged on one side X1 in the first direction X with respect to the printed circuit board 20. The plurality of electrolytic capacitors 60 are housed in housing recesses 11z formed in the base member 11. Each electrolytic capacitor 60 is formed, for example, in a cylindrical shape. Each electrolytic capacitor 60 is arranged with its axial direction aligned with the first direction X. The plurality of electrolytic capacitors 60 are arranged in parallel in the second direction Y. In this embodiment, for example, eight electrolytic capacitors 60 are arranged in parallel in the second direction Y.

[0023] As shown in FIG. 3 , each electrolytic capacitor 60 has a first lead terminal 61 and a second lead terminal 62. The first lead terminal 61 and the second lead terminal 62 are spaced apart in the second direction Y. The first lead terminal 61 is connected to the first bus bar 31. The second lead terminal 62 is connected to the second bus bar 32. In this manner, the electrolytic capacitor 60 is electrically connected to the switching element 22 via the bus bar 30. The electrolytic capacitor 60 suppresses fluctuations in DC voltage caused by the switching operation of the switching element 22. In the embodiment, the electrolytic capacitor 60 is used as an example of the capacitor, but the capacitor is not limited to the electrolytic capacitor 60. As another example, for example, a capacitor having a sufficiently large capacitance capable of suppressing fluctuations in DC voltage within a target value may be used.

[0024] 3 and 4 , the terminal connection members 80 are provided on the other side X2 in the first direction X with respect to the multiple switching elements 22. The multiple terminal connection members 80 are provided in parallel in the second direction Y. In the present embodiment, five terminal connection members 80 are provided lined up in the second direction Y.

[0025] Each terminal connecting member 80 extends in the first direction X. Each terminal connecting member 80 has an element connecting portion 81 on one side X1 in the first direction X. As shown in FIG. 3 , of the five terminal connecting members 80, the element connecting portions 81 of three terminal connecting members 80A arranged in the center in the second direction Y are fixed to the printed circuit board 20 with screws 88 and connected to the plurality of switching elements 22 via a wiring pattern (not shown) formed on the surface 20 a of the printed circuit board 20. Of the five terminal connecting members 80, the element connecting portions 81 of two terminal connecting members 80B provided at both ends in the second direction Y are fixed to the printed circuit board 20 with screws 88 and connected to a wiring pattern (not shown) formed on the surface 20 a of the printed circuit board 20.

[0026] As shown in Figures 3 and 4, each terminal connecting member 80 has a terminal portion 82 on the other side X2 in the first direction X. The terminal portion 82 of each terminal connecting member 80 is fixed to a spacer 15 attached to the first surface 11f of the base member 11. The spacer 15 extends in the second direction Y when viewed from the plate thickness direction Z. The spacer 15 has a predetermined thickness in the plate thickness direction Z. The spacer 15 is formed with an accommodation groove 15m that extends in the first direction X and accommodates the terminal portion 82. The accommodation groove 15m is recessed from the surface 15f of the spacer 15 toward the second side Z2 in the plate thickness direction Z. The surface 15f of the spacer 15 and the surface 82f of the terminal portion 82 accommodated in the accommodation groove 15m are along the same plane that intersects the plate thickness direction Z.

[0027] The spacer 15 has, at both ends in the second direction Y, locking portions 15s that protrude toward the second side Z2 in the plate thickness direction Z. The spacer 15 is so-called snap-fit ​​by locking the locking portions 15s with locking claws 11t formed on the base member 11.

[0028] External wiring (not shown) is detachably connected to the terminal portion 82 by a bolt 83 and a nut (not shown). As shown in Fig. 4, a bolt accommodating hole 15h that accommodates a head 83a of the bolt 83 is formed in the spacer 15. A shaft 83b of the bolt 83 penetrates the terminal portion 82 and protrudes toward a first side Z1 in the plate thickness direction Z relative to the terminal portion 82.

[0029] Here, of the five terminal connection members 80, the terminal portions 82 of the three terminal connection members 80A arranged in the center in the second direction Y are connected to external wiring for supplying U-phase, V-phase, and W-phase drive currents to a motor (not shown). Of the five terminal connection members 80, the terminal portions 82 of the two terminal connection members 80B arranged at both ends in the second direction Y are connected to external wiring for connection to a power source and ground.

[0030] 1 , 2 , and 4 , the base member 11 is provided with a plurality of heat dissipation fins 14 in a portion where the printed circuit board 20 and the plurality of electrolytic capacitors 60 are housed. The plurality of fins 14 are provided at intervals in the second direction Y. Each fin 14 protrudes from the base member 11 to the second side Z2 in the plate thickness direction Z and extends in the first direction X. The plurality of fins 14 dissipate heat generated by the plurality of electrolytic capacitors 60, the bus bar 30 mounted on the printed circuit board 20, the plurality of switching elements 22, the plurality of terminal connection members 80, etc., to the outside of the base member 11.

[0031] Figure 5 is a plan view of the motor control device 1 of Figure 1. As shown in Figures 1, 2, and 5, the base member 11 is provided with stays 16 that protrude on both sides in the second direction Y. The base member 11 (motor control device 1) is fixed to a vehicle body equipped with a motor (not shown) by bolts (not shown) inserted through the stays 16.

[0032] <Main cover 12> Figure 6 is a perspective view showing the motor control device 1 of Figure 1 with the sub-cover 13 removed. As shown in Figures 4 and 6, the main cover 12 is provided to cover the plurality of electrolytic capacitors 60 housed in the base member 11 and the printed circuit board 20. As shown in Figures 1, 2, and 5, the main cover 12 integrally has a plate-like portion 121 and a peripheral wall portion 122, and is formed in a box shape that is open to the second side Z2 in the plate thickness direction Z.

[0033] The plate-shaped portion 121 extends along a plane intersecting the plate thickness direction Z. The plate-shaped portion 121 is formed in a rectangular shape when viewed from the plate thickness direction Z. The dimension of the plate-shaped portion 121 in the Y direction is equal to that of the base member 11. The dimension of the plate-shaped portion 121 in the X direction is smaller than that of the base member 11. Therefore, when viewed from the plate thickness direction Z, the base member 11 protrudes toward the other side X2 in the first direction X relative to the plate-shaped portion 121.

[0034] The peripheral wall portion 122 rises from four sides of the plate-shaped portion 121 toward a second side Z2 in the plate thickness direction Z. Here, in the peripheral wall portion 122, the wall portion 122a provided on one side X1 in the first direction X and the wall portions 122b, 122c provided on both sides in the second direction Y are positioned to overlap with three side surfaces 11a, 11b, and 11c along the outer periphery of the base member 11, respectively, as viewed from the plate thickness direction Z. As shown in FIGS. 4 and 6 , in the peripheral wall portion 122, the wall portion 122d provided on the other side X2 in the first direction X is positioned toward the one side X1 in the first direction X with respect to the remaining side surface 11d along the outer periphery of the base member 11. As a result, the terminal portions 82 of the multiple terminal connection members 80 protrude from the wall portion 122d toward the other side X2 in the first direction X.

[0035] 1, 2, and 5, the peripheral wall portion 122 has a flange portion 123 extending outward from the distal end portion of the second side Z2 in the thickness direction Z. The flange portions 123a, 123b, and 123c of the walls 122a, 122b, and 122c are in close contact with the outer peripheral edge portion of the first surface 11f of the base member 11 via a sealant such as a liquid gasket. In this case, the space of the case 10 surrounded by the base member 11 and the main cover 12 constitutes the first space 100A.

[0036] 6, flange portion 123d connected to wall portion 122d is in close contact with surface 15f of spacer 15 and the surface of terminal portion 82 via a sealant such as a liquid gasket. In this manner, the electrolytic capacitors 60 and printed circuit board 20 are housed in a space sealed by base member 11, spacer 15, and main cover 12.

[0037] 1 and 2 , the main cover 12 has, at both ends in the second direction Y, latched portions 12s that protrude toward the second side Z2 in the plate thickness direction Z. The main cover 12 is so-called snap-fit ​​by latching the latched portions 12s onto latching claws 11k formed on the side surfaces 11b and 11c of the base member 11.

[0038] <Sub-cover 13> As shown in Figures 2 and 4, the sub-cover 13 is provided on the other side X2 in the first direction X with respect to the main cover 12. The sub-cover 13 is formed in a box shape that opens to the second side Z2 in the plate thickness direction Z and to one side X1 in the first direction. The sub-cover 13 is provided to cover the terminal portions 82 of the multiple terminal connection members 80 that protrude from the wall portion 122d of the main cover 12 to the other side X2 in the first direction X. The sub-cover 13 integrally includes a base portion 131 and a side wall portion 132. The base portion 131 extends along a plane that intersects with the plate thickness direction Z. The base portion 131 is formed in a rectangular shape when viewed from the plate thickness direction Z. The base portion 131 is provided on the same plane as the plate-shaped portion 121 of the main cover 12.

[0039] The side wall portion 132 rises from the outer peripheral edge of the base portion 131 toward a second side Z2 in the plate thickness direction Z. The side wall portion 132 has a wall portion 132a provided on the other side X2 in the first direction X and wall portions 132b and 132c provided on both sides in the second direction Y. The sub-cover 13 is open toward the second side Z2 in the plate thickness direction Z and one side X1 in the first direction X by the base portion 131 and the side wall portion 132.

[0040] The sub-cover 13 also has a plurality of protrusions 134 that protrude from the wall portion 132a toward the second side Z2 in the plate thickness direction Z and toward the other side X2 in the first direction X. The protrusions 134 are arranged at intervals in the second direction Y. As shown in FIG. 4 , the surface of each protrusion 134 facing the second side Z2 in the plate thickness direction Z is formed with wiring insertion holes 134h through which external wiring is inserted. Ends of the external wiring are drawn into the sub-cover 13 through the wiring insertion holes 134h and then individually connected to terminal portions 82 within the sub-cover 13. As shown in FIG. 5 , the sub-cover 13 is detachably fixed to the side surface 11d of the base member 11 with screws 135.

[0041] 7 is an enlarged cross-sectional view showing a contact portion between the main cover 12 and the sub-cover 13. As shown in FIGS. 5 and 7, an edge 131s on one side X1 in the first direction X of the base 131 of the sub-cover 13 contacts the wall portion 122d of the main cover 12. Specifically, the edge 131s abuts against the wall portion 122d from the other side X2 in the first direction X. However, the edge 131s may overlap the wall portion 122d or the plate-like portion 121 from the first side Z1 in the plate thickness direction Z, as long as the main cover 12 and the sub-cover 13 are configured to be in close contact with each other.

[0042] In the case 10, the space surrounded by the base member 11 and the sub-cover 13 forms a second space 100B. The first space 100A and the second space 100B are separated by a wall portion 122d.

[0043] <Filter 128> Figure 8 is a cross-sectional view taken along the line I-I in Figure 4. Figure 9 is an enlarged cross-sectional view showing the filter 128 and the filter cover portion 138 of the motor control device 1. As shown in Figures 4, 6, 8, and 9, the filter 128 is provided on the main cover 12. A communication hole 125 is formed in the end of the plate-shaped portion 121 on the other side X2 in the first direction X. The communication hole 125 is formed in the center of the plate-shaped portion 121 in the second direction Y. The communication hole 125 is formed in the bottom wall 126b of the recess 126 formed in the plate-shaped portion 121.

[0044] The recess 126 is recessed from an outer surface 121f of the plate-shaped portion 121 facing a first side Z1 in the plate thickness direction Z toward a second side Z2 in the plate thickness direction Z. The recess 126 is formed, for example, in a U-shape when viewed from the plate thickness direction Z. The recess 126 has a bottom wall 126b and a peripheral wall 126s. The bottom wall 126b is provided on the second side Z2 in the plate thickness direction Z with respect to the plate-shaped portion 121. The bottom wall 126b extends along a plane intersecting the plate thickness direction Z. An end of the bottom wall 126b on the other side X2 in the first direction X is connected to the wall portion 122d. The peripheral wall 126s extends in a U-shape along the outer peripheral edge of the bottom wall 126b when viewed from the plate thickness direction Z. The peripheral wall 126s connects the outer peripheral edge of the bottom wall 126b to the plate-shaped portion 121. The recess 126 opens onto the outer surface 121f and onto a surface of the wall portion 122d facing the other side X2 in the first direction X.

[0045] The communication hole 125 penetrates the bottom wall 126b of the recess 126 in the thickness direction Z. This allows communication between the interior and exterior of the case 10 (first space 100A). The peripheral wall 126s also includes a step 126d at an end on a first side Z1 in the thickness direction Z. The step 126d has an inner diameter dimension of the recess 126 enlarged in a direction intersecting the thickness direction Z relative to an end on a second side Z2 in the thickness direction Z. The inner peripheral surface of the step 126d includes a vertical surface 126g extending from the opening edge of the recess 126 on the first side Z1 in the thickness direction Z to the second side Z2 in the thickness direction Z, and a stepped surface 126f extending from the end of the vertical surface 126g on the second side Z2 in the thickness direction Z toward the inside of the recess 126.

[0046] The filter 128 is provided in the recess 126 so as to cover the communication hole 125. The filter 128 is made of a material that allows air to pass through but prevents the penetration of rainwater and foreign matter. In this embodiment, the communication hole 125 and the filter 128 are formed, for example, in a circular shape when viewed in the plate thickness direction Z. The filter 128 may be adhered or welded to a portion of the bottom wall 126b that is positioned around the communication hole 125, or may simply be placed on the bottom wall 126b.

[0047] As shown in Figures 1, 2, 4, 5, and 9, the sub-cover 13 is provided with a filter cover portion 138. The filter cover portion 138 is integrally formed with the end portion of the base portion 131 on one side X1 in the first direction X. The filter cover portion 138 is provided in the center portion in the second direction Y. The filter cover portion 138 is provided so as to protrude from the base portion 131 toward the one side X1 in the first direction X. The filter cover portion 138 is provided on the same plane as the base portion 131. The filter cover portion 138 is formed, for example, in a substantially U-shape when viewed from the plate thickness direction Z. In the illustrated example, the plate thickness of the filter cover portion 138 gradually becomes thinner toward the one side X1 in the first direction X.

[0048] 4, 8, and 9, the filter cover portion 138 is provided in the recess 126 so as to face the bottom wall 126b in the plate thickness direction Z, with the filter 128 sandwiched therebetween. The filter cover portion 138 is spaced apart from the filter 128 on one side X1 in the plate thickness direction Z.

[0049] A small gap S is provided between the filter cover portion 138 and the recess 126 when viewed from the plate thickness direction Z. The gap S is set to a dimension that allows gas to pass through but prevents liquid and dust from passing through. More specifically, as shown in FIG. 9 , when viewed from the second direction Y, a tip portion 138s on one side X1 in the first direction X of the outer periphery of the filter cover portion 138 is disposed within the step portion 126d (when viewed from the plate thickness direction Z, it overlaps with the step portion 126d). Within the step portion 126d, the tip portion 138s is spaced apart in the first direction X from the hanging surface 126g. Within the step portion 126d, the tip portion 138s is spaced apart on the first side Z1 in the plate thickness direction Z from the step surface 126f.

[0050] As shown in FIG. 8 , the filter cover portion 138 has two end portions 138e on both sides of its outer periphery in the second direction Y, which are located within the step 126d (overlapping the step 126d when viewed from the thickness direction Z). The end portions 138e are spaced apart from the vertically extending surface 126g in the first direction X within the step 126d. The end portions 138e are spaced apart from the step surface 126f on the first side Z1 in the thickness direction Z within the step 126d. Therefore, the gap S extends around the entire periphery between the outer periphery of the filter cover portion 138 and the inner periphery of the peripheral wall 126s in an L-shaped cross section. This prevents rainwater and other foreign objects from entering through the gap S. Furthermore, because the outer peripheral edge of the filter cover portion 138 (the tip portion 138s and the end portion 138e) faces the step surface 126f in the plate thickness direction Z, when the filter cover portion 138 is deformed toward the second side Z2 in the plate thickness direction Z due to an external force or the like, the outer peripheral edge of the filter cover portion 138 abuts against the step surface 126f. This prevents excessive deformation of the filter cover portion 138. However, it is sufficient that at least a partial gap S is provided between the outer peripheral surface of the filter cover portion 138 and the inner peripheral surface of the peripheral wall 126s.

[0051] By providing such a filter cover portion 138, the first space 100A covered by the main cover 12 is connected to the outside through the communication hole 125, the filter 128, the space between the filter 128 and the filter cover portion 138, and the gap S.

[0052] As described above, in this embodiment, the filter 128 is provided to cover the communication hole 125 formed in the main cover 12, and the filter cover portion 138 covering the filter 128 is provided on the sub-cover 13. With this configuration, the filter cover portion 138 is provided to cover the filter 128, which prevents the filter 128 from being subjected to external forces such as high-pressure water or flying stones. This prevents water and dust from entering the case 10 and allows gas to enter and exit the case 10 due to pressure changes without using a special filter designed to protect against such external forces. Furthermore, because the sub-cover 13 has the filter cover portion 138 integrally therewith, the filter cover portion 138 covering the filter 128 is set in place by attaching the main cover 12 and the sub-cover 13 to the base member 11. Therefore, it is possible to provide a motor control device 1 equipped with the filter cover portion 138 in a simple configuration while minimizing an increase in the number of parts and assembly steps. Furthermore, since the motor control device 1 can be provided with a simple configuration while minimizing increases in the number of parts and assembly labor, it will be possible to contribute to Goal 7 of the United Nations-led Sustainable Development Goals (SDGs), which is to "Ensure access to affordable, reliable, sustainable and modern energy for all," and Goal 9, which is to "Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation."

[0053] In this embodiment, the filter 128 and the filter cover portion 138 are provided in the recess 126 formed in the main cover 12. This configuration allows the filter cover portion 138 that covers the filter 128 to be provided with a simple structure. Furthermore, by providing the filter cover portion 138 in the recess 126, the motor control device 1 can be configured compactly in the plate thickness direction Z.

[0054] In the present embodiment, the filter cover portion 138 is provided at a distance from the filter 128 on the first side Z1 in the plate thickness direction Z, and a gap S is formed between the filter cover portion 138 and the recess 126 when viewed from the plate thickness direction Z. This simple configuration allows for good ventilation between the inside and outside of the main cover 12 through the filter 128, while the filter cover portion 138 effectively prevents rainwater and foreign matter from reaching the filter 128 from the outside.

[0055] The present invention is not limited to the above-described embodiment, and includes various modifications to the above-described embodiment without departing from the spirit of the present invention. For example, in the above-described embodiment, the case 10 is provided with a plurality of electrolytic capacitors 60, a printed circuit board 20 on which a plurality of switching elements 22 are mounted, and a terminal connecting member 80, but the number and positions of these components can be changed as appropriate.

[0056] In the above-described embodiment, a configuration in which the communication hole 125 opens in the bottom wall 126b of the recess 126 has been described, but this configuration is not limited thereto. The communication hole 125 may be formed in, for example, the plate-shaped portion 121 or the peripheral wall portion 122. In the above-described embodiment, a configuration in which the communication hole 125 is provided in only one location has been described, but this configuration is not limited thereto. The communication hole 125 may be provided in multiple locations. In the above-described embodiment, a configuration in which the filter cover portion 138 is provided within the recess 126 has been described, but this configuration is not limited thereto. The filter cover portion 138 may be provided in a state in which it bulges out from the main cover 12.

[0057] In addition, within the scope of the spirit of the present invention, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described modifications may be combined as appropriate.

[0058] 1...Motor control device 10...Case 11...Base member 11a to 11d...Side surface 11f...First surface 11k, 11t...Latching claw 11z...Accommodating recess 12...Main cover 12s...Latched portion 13...Sub-cover 14...Fin 15...Spacer 15f...Surface 15h...Bolt accommodating hole 15m...Accommodating groove 15s...Latched portion 16...Stay 20...Printed circuit board (circuit board) 20a...Surface 22...Switching element 30...Bus bar 31...First bus bar 32...Second bus bar 60...Electrolytic capacitor 61...First lead terminal 62...Second lead terminal 80, 80A, 80B...Terminal connecting member 81...Element connecting portion 82...Terminal portion 82f...Surface 83...Bolt 83a...Head portion 83b...Shaft portion 88...Screw DESCRIPTION OF SYMBOLS 100A...First space 100B...Second space 121...Plate-shaped portion 121f...Outer surface 122...Circumferential wall portion 122a to 122d...Wall portion 123, 123a to 123d...Flange portion 125...Communicating hole 126...Recess 126b...Bottom wall 126d...Step portion 126f...Surface 126g...Surface 126s...Circumferential wall 128...Filter 131...Base portion 131s...Edge 132...Side wall portion 132a to 132c...Wall portion 134...Protrusion 134h...Wiring insertion hole 135...Screw 138...Filter cover portion 138e...End portion 138s...Tip portion S...Gap X...First direction X1...One side X2...Other side Y...Second direction Z...Plate thickness direction Z1...First side Z2...Second side

Claims

1. A motor control device comprising: a board on which switching elements for driving a motor are mounted; a terminal connection member having an element connection portion connected to the switching elements and terminal portions to which external wiring is detachably connected, the terminal connection member extending in a first direction along a main surface of the board; and a case accommodating the switching elements, the board, and the terminal connection member, wherein the case comprises: a base member having a first surface to which the board is fixed; a main cover covering at least a portion of the first surface of the base member on which the board is provided and attached to the base member with the terminal portions protruding in the first direction; a filter through which air can pass, the filter being provided so as to cover communication holes formed in the main cover that communicate between the inside and the outside of the case; and a sub-cover detachably provided on the base member so as to cover the terminal portions, the sub-cover having an integral filter cover portion provided to cover the filter.

2. A motor control device as described in claim 1, characterized in that the main cover has an outer surface facing a first side in the plate thickness direction of the board and a bottom wall into which the communication hole opens, and a recess in the outer surface opening to the first side in the plate thickness direction, the filter is arranged within the recess so as to cover the communication hole, and the filter cover part is arranged within the recess so as to face the bottom wall in the plate thickness direction with the filter in between.

3. A motor control device as described in claim 2, characterized in that the filter cover portion is spaced apart from the filter on a first side in the plate thickness direction, and when viewed from the plate thickness direction, a gap is formed between the filter cover portion and the recess.

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