Electronic substrate device and brake control device

Abstract

To provide an electronic substrate device capable of cutting off an overcurrent by a simple structure as an example.SOLUTION: An insulating member having a first outer surface and a second outer surface, the second outer surface facing in a direction different from a vertically upward direction; And a pattern including a first electronic component disposed on the first outer surface, a second electronic component disposed on the second outer surface, a brazing material, a terminal provided on the first outer surface and joined to the first electronic component, a pad provided on the second outer surface and joined to the second electronic component by the brazing material, a via penetrating the insulating material, a first wiring connecting the terminal and the via, and a second wiring connecting the pad and the via, wherein when the brazing material is melted, the second electronic component is separated from the pad by a weight of the second electronic component, so that energization of the first electronic component is cut off.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] An embodiment of the present invention relates to an electronic board device and a brake control device. [Background technology]

[0002] Conventionally, various devices, such as a brake control device, include an electronic board device that drives a load such as an actuator. The electronic board device has, for example, a fuse to cut off an overcurrent in the drive circuit (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-071126 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the conventional configuration, the addition of fuses can make the electronic board device more complicated.

[0005] Therefore, the present invention has been made in view of the above, and provides an electronic board device and a brake control device that are capable of interrupting an overcurrent with a simple structure. [Means for solving the problem]

[0006] As an example, an electronic board device according to an embodiment of the present invention includes an insulating material having a first outer surface and a second outer surface located opposite the first outer surface, the second outer surface being configured to face in a direction other than vertically upward; a pattern configured to generate heat when electricity is passed through the insulating material, the pattern including a first electronic component arranged on the first outer surface, a second electronic component arranged on the second outer surface, solder, a terminal provided on the first outer surface and joined to the first electronic component, a pad provided on the second outer surface and joined to the second electronic component by the solder, a via penetrating the insulating material, a first wiring connecting the terminal and the via, and a second wiring connecting the pad and the via, the pattern configured such that when the solder melts, the weight of the second electronic component moves away from the pad, thereby cutting off the flow of electricity to the first electronic component. For example, if an overcurrent occurs in the pattern, the temperature of the electronic board device rises due to heat generated by the first electronic component and the electrical resistance of the via, first wiring, and second wiring. When the temperature of the electronic board device exceeds the melting point of the solder, the solder melts, and the weight of the second electronic component separates it from the pad. This causes the pattern to cut off current to the first electronic component. Therefore, the electronic board device can cut off overcurrent with a simple structure without adding components such as fuses. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a cross-sectional view that schematically shows a brake system according to a first embodiment. [Figure 2] FIG. 2 is a plan view showing a part of the electronic substrate device according to the first embodiment. [Figure 3] FIG. 3 is a circuit diagram that schematically shows the configuration of a drive circuit for a motor in the brake control device of the first embodiment. [Figure 4] FIG. 4 is a cross-sectional view schematically showing a part of the electronic substrate device according to the first embodiment taken along line F4-F4 in FIG. [Figure 5] FIG. 5 is a cross-sectional view schematically showing a part of an electronic substrate device according to the second embodiment. [Figure 6] FIG. 6 is a cross-sectional view schematically showing a part of an electronic substrate device according to a third embodiment. [Figure 7] FIG. 7 is a cross-sectional view schematically showing a part of an electronic substrate device according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] (First embodiment) A first embodiment will be described below with reference to FIGS. 1 to 4. In this specification, the vertically upward direction is basically defined as the upward direction, and the vertically downward direction is basically defined as the downward direction. In addition, in this specification, components according to the embodiment and their descriptions may be described using multiple expressions. The components and their descriptions are merely examples and are not limited by the expressions in this specification. The components may also be identified by names different from those in this specification. The components may also be described using expressions different from those in this specification.

[0009] In the following description, "inhibit" is defined as, for example, preventing an event, action, or effect from occurring or reducing the magnitude of an event, action, or effect.

[0010] 1 is a cross-sectional view that schematically shows a brake system 10 according to a first embodiment. The brake system 10 is mounted on a vehicle 1 such as a four-wheeled automobile. However, the brake system 10 is not limited to this example.

[0011] The brake system 10 includes a brake control device 11 and a plurality of wheel cylinders 12. The brake control device 11 may also be referred to as a brake fluid pressure control device. The brake system 10 may further include various other components such as a master cylinder, a pump, and a solenoid valve.

[0012] The brake control device 11 controls, for example, the hydraulic pressure of at least one of the plurality of wheel cylinders 12. The brake control device 11 includes an electric cylinder device 21, an electronic control unit (ECU) 22, and a plurality of hydraulic paths 23.

[0013] The electric cylinder device 21 is connected to at least one of the plurality of wheel cylinders 12 via a fluid path 23. The electric cylinder device 21 can increase the pressure of the brake fluid in the wheel cylinder 12 to generate a braking force for the vehicle 1.

[0014] The electric cylinder device 21 has a motor 25 and a pressure adjusting device 26. The motor 25 is an example of a load and an actuator. The actuator is not limited to the motor 25, and may be another actuator such as a solenoid actuator. The load is not limited to the actuator, and may be another device that consumes power.

[0015] The motor 25 is, for example, a three-phase brushless motor. However, other types of motors may be used as the motor 25. The motor 25 is controlled by the ECU 22, for example, to drive the pressure regulator 26.

[0016] The pressure regulating device 26 includes a housing 31, a piston 32, two seals 33 and 34, a reservoir 35, a rotary-to-linear motion conversion mechanism 36, and a speed reduction mechanism 37. The ECU 22 and the motor 25 are located outside the housing 31. However, the ECU 22 and the motor 25 may be located inside the housing 31.

[0017] An internal space 41 is provided inside the housing 31. The internal space 41 is a substantially cylindrical space extending along a central axis Axc. The central axis Axc is, for example, a virtual central axis of the internal space 41. Note that the central axis of the internal space 41 may be different from the central axis Axc.

[0018] For convenience, the axial direction and the radial direction are defined herein. The axial direction is a direction along the central axis Axc. The axial direction includes a forward direction Df and a rearward direction Db. The forward direction Df is a direction along the central axis Axc. The rearward direction Db is the opposite direction to the forward direction Df. The radial direction is a direction perpendicular to the central axis Axc.

[0019] The housing 31 is further provided with an output port 42 and an input port 43. The output port 42 and the input port 43 each communicate with the internal space 41. In the axial direction, the output port 42 is spaced apart from the input port 43 in the forward direction Df.

[0020] The piston 32 is disposed in the internal space 41. The piston 32 is able to move axially within the internal space 41. The piston 32 defines a portion of the internal space 41 as a fluid chamber 45. That is, the fluid chamber 45 is provided in the pressure adjusting device 26. The fluid chamber 45 is provided axially between the piston 32 and the end of the internal space 41 in the forward direction Df. The fluid chamber 45 is filled with brake fluid. In other words, the fluid chamber 45 contains brake fluid.

[0021] The output port 42 is connected to a fluid chamber 45. The fluid chamber 45 is connected to the wheel cylinder 12 through the output port 42 and the fluid passage 23. The piston 32 reduces the volume of the fluid chamber 45 by moving forward Df. This allows the electric cylinder device 21 to increase the pressure of the brake fluid in the fluid chamber 45 and the wheel cylinder 12.

[0022] On the other hand, the piston 32 moves in the rear direction Db to increase the volume of the fluid chamber 45. This allows the electric cylinder device 21 to reduce the pressure of the brake fluid in the fluid chamber 45 and the wheel cylinder 12.

[0023] A gap is provided between the housing 31 and the piston 32 in the radial direction, allowing the piston 32 to move axially relative to the housing 31. Two seals 33, 34 seal the gap.

[0024] The seal 33 is spaced from the seal 34 in the forward direction Df. In the axial direction, the output port 42 communicates with the liquid chamber 45 at a position spaced from the seal 33 in the forward direction Df. In the axial direction, the input port 43 communicates with the internal space 41 between the two seals 33, 34. The seal 33 seals between the liquid chamber 45 and the input port 43.

[0025] The reservoir 35 is connected to the input port 43 through the fluid path 23. The reservoir 35 stores brake fluid. For example, the reservoir 35 is open to the atmosphere, so that the pressure of the reservoir 35 is maintained at atmospheric pressure.

[0026] When the piston 32 moves rearward Db beyond a predetermined position, the input port 43 and the fluid chamber 45 communicate with each other. This allows the brake fluid to flow freely between the fluid chamber 45 and the reservoir 35, and the pressure in the fluid chamber 45 drops to atmospheric pressure.

[0027] The rotary-to-linear motion conversion mechanism 36 is disposed in the internal space 41. In this embodiment, the rotary-to-linear motion conversion mechanism 36 is, for example, a ball screw. The rotary-to-linear motion conversion mechanism 36 has a rotating member 51, a linear motion member 52, and a plurality of balls 53.

[0028] The rotating member 51 is formed in a generally cylindrical shape extending along the central axis Axc. The linear moving member 52 is formed in a generally cylindrical shape extending along the central axis Axc. The rotating member 51 extends through a hole inside the linear moving member 52. The linear moving member 52 is attached to or supports the piston 32.

[0029] A male screw is provided on the rotating member 51. On the other hand, a female screw is provided on the linear moving member 52. The linear moving member 52 may further be provided with a circulation path connecting both ends of the female screw. The plurality of balls 53 are, for example, held by the female screw of the linear moving member 52 so as to be able to roll and circulate, and are fitted into the male screw of the rotating member 51. Therefore, the linear moving member 52 is attached to the rotating member 51 via the balls 53.

[0030] The speed reduction mechanism 37 has a plurality of gears that mesh with each other. The speed reduction mechanism 37 is not limited to the example shown in Figure 1, and may be another speed reduction mechanism such as a planetary gear mechanism. The speed reduction mechanism 37 is provided between the motor 25 and the rotating member 51.

[0031] The motor 25 rotates the rotating member 51 around the central axis Axc through the speed reduction mechanism 37. The speed reduction mechanism 37 may be omitted. For example, the motor 25 may rotate the rotating member 51 directly.

[0032] When the motor 25 rotates the rotating member 51 in one direction (forward direction) around the central axis Axc, the rotating member 51 pushes the linearly moving member 52 in the forward direction Df via the ball 53. Furthermore, the linearly moving member 52 pushes the piston 32 in the forward direction Df. As a result, the linearly moving member 52 and the piston 32 move (advance) in the forward direction Df. By moving in the forward direction Df, the piston 32 reduces the volume of the liquid chamber 45 and increases the pressure in the liquid chamber 45.

[0033] On the other hand, when the motor 25 rotates the rotating member 51 in the direction opposite to the forward rotation direction (reverse direction), the rotating member 51 pushes the linearly moving member 52 in the rearward direction Db via the ball 53. The piston 32 moves (retracts) in the rearward direction Db together with the linearly moving member 52. By moving in the rearward direction Db, the piston 32 increases the volume of the liquid chamber 45 and reduces the pressure in the liquid chamber 45. As described above, the pressure adjusting device 26 is driven by the motor 25 to change the pressure in the liquid chamber 45.

[0034] The ECU 22 has a case 61 and an electronic board device 62. The case 61 houses the electronic board device 62. The case 61 is sealed watertight to protect the electronic board device 62. However, the case 61 is not limited to this example.

[0035] Fig. 2 is a plan view showing a portion of an electronic board device 62 according to the first embodiment. As shown in Fig. 2, the electronic board device 62 includes a board 71, an inductor 72, and a capacitor 73. The inductor 72 is an example of a second electronic component.

[0036] 3 is a circuit diagram that schematically illustrates the configuration of a drive circuit for the motor 25 in the brake control device 11 of the first embodiment. As illustrated in FIG. 3, the electronic board device 62 further includes an inverter circuit 74 and a power transistor 75. The power transistor 75 is an example of a first electronic component. The electronic board device 62 further includes a microcontroller, a sensor, a capacitor, and various other components.

[0037] The electronic board device 62 is connected to a power source P. The electronic board device 62 supplies power to the motor 25 through the inductor 72, the power transistor 75, and the inverter circuit 74, thereby driving the motor 25.

[0038] The inverter circuit 74 includes semiconductor elements such as multiple metal oxide semiconductor field effect transistors (MOSFETs). The inverter circuit 74 may include other types of transistors or other electronic components. The inverter circuit 74 generates U-phase, V-phase, and W-phase drive signals (currents) from the power supply voltage supplied from the power supply P and supplies the drive signals to the motor 25.

[0039] The power transistor 75 is provided between the inverter circuit 74 and the power supply P. The power transistor 75 is a semiconductor element such as a MOSFET. However, the power transistor 75 is not limited to this example. The power transistor 75 switches the power supply to the motor 25. In other words, the power transistor 75 is a semiconductor element that drives the motor 25.

[0040] The inductor 72 is provided between the power transistor 75 and the power supply P. The inductor 72, for example, removes noise from the current supplied to the power transistor 75. Note that the inductor 72 is not limited to this example.

[0041] An inductor 72, a capacitor 73, a MOSFET of an inverter circuit 74, and a power transistor 75 are mounted on the substrate 71. Other components such as a microcontroller, sensors, and capacitors are also mounted on the substrate 71.

[0042] 4 is a cross-sectional view schematically showing a portion of the electronic board device 62 of the first embodiment taken along line F4-F4 in FIG. 2. As shown in FIG. 4, the board 71 of this embodiment is a multilayer printed wiring board. However, the board 71 is not limited to this example. The board 71 has an insulating material 81, a pattern 82, and two solder resists 83 and 84. For ease of understanding, the solder resist 83 is omitted from FIG. 2.

[0043] As shown in Fig. 4, the insulating material 81 has a plurality of laminated insulating layers 90. The plurality of insulating layers 90 are made of, for example, synthetic resin. Note that the material of the insulating layers 90 is not limited to this example. The plurality of insulating layers 90 includes two outer layers 91 and 92 and a plurality of inner layers 93. Note that the inner layer 93 may be omitted.

[0044] Each of the outer layers 91 and 92 is one of the outermost layers among the plurality of stacked insulating layers 90. Each of the inner layers 93 is one of the plurality of stacked insulating layers 90 that is located between the two outer layers 91 and 92.

[0045] The insulating material 81 further has two flat outer surfaces 81a and 81b. The outer surface 81a is an example of a second outer surface. The outer surface 81b is an example of a first outer surface. The outer surface 81a is located opposite the outer surface 81b.

[0046] The outer surfaces 81a and 81b are provided on both ends of the insulating material 81 in the direction in which the multiple insulating layers 90 are stacked. The outer surface 81a is one surface of the outer layer 91. The outer surface 81b is one surface of the outer layer 92. The multiple insulating layers 90 are located between the two outer surfaces 81a and 81b of the insulating material 81.

[0047] In this embodiment, the substrate 71 is disposed so that the outer surface 81a faces in a substantially horizontal direction. That is, the outer surface 81a faces in a direction other than vertically upward. However, the orientation of the outer surface 81a is not limited to this example. The outer surface 81a may face vertically downward, or may be inclined relative to the vertical and horizontal directions. The outer surface 81b may face vertically upward.

[0048] The pattern 82 is a conductor provided on the insulating material 81. The pattern 82 has a plurality of conductive layers 101 and a plurality of vias 102. Note that the pattern 82 may further include other patterns. The conductive layers 101 and the vias 102 are made of a metal such as copper.

[0049] The plurality of conductive layers 101 includes two outer layers 105 and 106 and a plurality of inner layers 107. The outer layer 105 is one of the plurality of conductive layers 101 that is provided on the outer surface 81a of the insulating material 81. The outer layer 106 is one of the plurality of conductive layers 101 that is provided on the outer surface 81b of the insulating material 81. Each of the plurality of inner layers 107 is one of the plurality of conductive layers 101 that is provided between two adjacent ones of the plurality of insulating layers 90.

[0050] The vias 102 are, for example, plated through holes. However, the vias 102 may be other vias. Each of the vias 102 penetrates the insulating material 81 and connects at least two of the conductive layers 101.

[0051] The solder resist 83 covers the outer surface 81a of the insulating material 81 and a part of the outer layer 105 of the conductive layer 101. The solder resist 84 covers the outer surface 81b of the insulating material 81 and a part of the outer layer 106 of the conductive layer 101. The solder resists 83 and 84 cover, for example, the wiring of the outer layers 105 and 106, and expose the pads.

[0052] 2, the pattern 82 has a drive wiring 111 and a ground pattern 112. The drive wiring 111 is provided between the power source P and the motor 25, and a current supplied to the motor 25 flows through the drive wiring 111.

[0053] As shown in Figure 4, the drive wiring 111 has multiple external patterns 121, 122, 123, and 124, multiple internal patterns 125 and 126, multiple mounting pads 131, 132, 133, and 134, and multiple vias 135 and 136. The external pattern 122 is an example of a second wiring. The external pattern 123 is an example of a first wiring. The mounting pad 132 is an example of a pad. The mounting pad 133 is an example of a terminal.

[0054] The external patterns 121 and 122 and the mounting pads 131 and 132 are included in the outer layer 105 of the conductive layer 101. That is, the external patterns 121 and 122 and the mounting pads 131 and 132 are provided on the outer surface 81a of the insulating material 81.

[0055] Mounting pad 131 is provided at one end of external pattern 121. Mounting pad 132 is provided at one end of external pattern 122. Mounting pads 131 and 132 are not covered with solder resist 83 and are exposed. Mounting pad 132 is located lower than mounting pad 131.

[0056] The external patterns 123, 124 and the mounting pads 133, 134 are provided on the outer layer 106 of the conductive layer 101. That is, the external patterns 123, 124 and the mounting pads 133, 134 are provided on the outer surface 81b of the insulating material 81.

[0057] The mounting pad 133 is provided at one end of the external pattern 123. The mounting pad 134 is provided at one end of the external pattern 124. The external pattern 124 is electrically connected to the motor 25 via the inverter circuit 74. The mounting pads 133, 134 are not covered with the solder resist 84 and are exposed. The mounting pad 134 is located lower than the mounting pad 133.

[0058] The internal patterns 125 and 126 are included in the inner layer 107 of the conductive layer 101. That is, each of the multiple internal patterns 125 and 126 is provided between two adjacent ones of the multiple insulating layers 90.

[0059] Vias 135 and 136 are included in the plurality of vias 102. That is, vias 135 and 136 penetrate insulating material 81. Via 135 is connected to external patterns 122 and 123 and the plurality of internal patterns 125 and 126. Therefore, external pattern 122 connects mounting pad 132 and via 135. External pattern 123 connects mounting pad 133 and via 135. Via 136 is connected to external pattern 124.

[0060] 2, the drive wiring 111 further includes a plurality of power supply terminals 137 and a plurality of test pads 138. The test pads 138 are an example of first electrodes.

[0061] The power supply terminal 137 is, for example, a plated through hole and is included in the plurality of vias 102. Therefore, the power supply terminal 137 penetrates the insulating material 81. The power supply terminal 137 is connected to a power supply P. Note that the power supply terminal 137 may be another terminal such as a pad.

[0062] The power supply terminal 137 is connected to the external pattern 121. Therefore, the external pattern 121 connects the power supply terminal 137 and the mounting pad 131. The mounting pad 131 is electrically connected to the power supply P through the external pattern 121. Note that other wiring or other electronic components may be provided between the power supply terminal 137 and the mounting pad 131.

[0063] The test pad 138 is part of the external pattern 122 and is exposed without being covered by the solder resist 83. That is, the test pad 138 is provided on the outer surface 81a of the insulating material 81 and has approximately the same potential as the power supply P, for example. The test pad 138 is located lower than the mounting pads 131 and 132.

[0064] The ground pattern 112 is set to a ground potential and includes an external ground plane 141 and a plurality of test pads 142. The test pads 142 are an example of a second electrode.

[0065] The external ground plane 141 is included in the outer layer 105 of the conductive layer 101. That is, the external ground plane 141 is provided on the outer surface 81a of the insulating material 81. The external ground plane 141 and the external patterns 121 and 122 of the drive wiring 111 are spaced apart from each other.

[0066] The test pads 142 are part of the external ground plane 141 and are exposed without being covered by the solder resist 83. That is, the test pads 142 are provided on the outer surface 81a of the insulating material 81 and are at ground potential. The test pads 142 have a different potential from the test pads 138. The test pads 142 are located below the mounting pads 131.

[0067] The inductor 72 and the capacitor 73 are disposed on the outer surface 81a of the insulating material 81. The inductor 72 has two terminals 151 and 152. The terminal 151 is an example of a second component terminal. The terminal 152 is an example of a first component terminal. The terminal 151 is spaced apart from the terminal 152. The terminal 152 is located lower than the terminal 151.

[0068] 4, the electronic board device 62 further includes a plurality of solders S1, S2, S3, and S4. The solders S1, S2, S3, and S4 are examples of solder. The mounting pad 131 is joined to a terminal 151 of the inductor 72 by the solder S1. The mounting pad 132 is joined to a terminal 152 of the inductor 72 by the solder S2. In this way, the inductor 72 is mounted on the board 71.

[0069] The internal patterns 125 and 126 overlap the mounting pads 131 and 132 and the solders S1 and S2 in a direction perpendicular to the outer surface 81b (hereinafter referred to as the thickness direction). The internal pattern 125 may overlap one of the solders S1 and S2.

[0070] 2, the via 135 and the test pads 138 and 142 are located below the inductor 72. The distance between the test pad 138 and the test pad 142 is greater than the distance between the two terminals 151 and 152 of the inductor 72.

[0071] The capacitor 73 is connected to the external pattern 121 of the drive wiring 111 and to the external ground plane 141 of the ground pattern 112. The capacitor 73 is adjacent to the inductor 72 in the substantially horizontal direction.

[0072] 4, the power transistor 75 is disposed on the outer surface 81b of the insulating material 81. At least a portion of the power transistor 75 overlaps the external pattern 122 in the thickness direction. Note that the position of the power transistor 75 is not limited to this example.

[0073] The power transistor 75 has two terminals 161 and 162. The mounting pad 133 is joined to the terminal 161 of the power transistor 75 by solder S3. The mounting pad 134 is joined to the terminal 162 of the power transistor 75 by solder S4. In this way, the power transistor 75 is mounted on the substrate 71, and the inductor 72 and power transistor 75 are connected in series between the power source P and the motor 25. The power transistor 75 may also be mounted on the substrate 71 by insertion mounting technology.

[0074] When power transistor 75 is energized, it generates more heat than inductor 72 and capacitor 73. On the other hand, inductor 72 is larger than power transistor 75.

[0075] The inductor 72 is heavier than both the capacitor 73 and the power transistor 75. For example, the mass of the inductor 72 is 20 times or more the mass of the power transistor 75. However, the mass of the inductor 72 is not limited to this example.

[0076] 2, a lower space Sd is provided in the ECU 22. The lower space Sd is located below the inductor 72 and is adjacent to the inductor 72. The lower space Sd exists, for example, in a region of the outer surface 81a of the insulating material 81 where no components are attached, and is a space capable of accommodating the inductor 72. When the outer surface 81a faces vertically downward, the lower space Sd is provided, for example, between the inductor 72 and the case 61.

[0077] For example, in the lower space Sd, the distance between the case 61 and the board 71 is greater than the thickness of the inductor 72. Therefore, when the inductor 72 is not mounted on the board 71, it can be placed in the lower space Sd without interfering with the case 61.

[0078] If a fault occurs in the electrical path between the power supply P and the motor 25, an overcurrent may flow through the drive wiring 111. However, the electronic board device 62 of this embodiment can cut off the overcurrent before the overcurrent causes burnout, for example.

[0079] For example, when an overcurrent flows, the power transistor 75 generates more heat than usual. As shown by the arrows in FIG.

[0080] The metal drive wiring 111 has a higher thermal conductivity than the insulating material 81. Therefore, the heat of the power transistor 75 is efficiently conducted to the solders S1 and S2 through the external pattern 123, the via 135, and the external pattern 122, for example.

[0081] As described above, the power transistor 75 overlaps the external pattern 122 in the thickness direction. Therefore, the heat of the power transistor 75 is efficiently transferred through the external pattern 122 to the solders S1 and S2.

[0082] Furthermore, when an overcurrent flows through the drive wiring 111, heat is generated due to electrical resistance. As described above, the internal patterns 125 and 126 overlap the solders S1 and S2 in the thickness direction. Therefore, the internal patterns 125 and 126 heat the solders S1 and S2.

[0083] The solders S1 and S2 melt when the substrate 71 and the power transistor 75 are heated. The melting points of the solders S1 and S2 are within the rated temperature range of the electronic substrate device 62. Therefore, when the solders S1 and S2 melt, the temperatures of the inductor 72, the capacitor 73, the inverter circuit 74, and the power transistor 75 are lower than the upper limit of the rated temperature.

[0084] The interfacial tension (surface tension) of the molten solders S1 and S2 is smaller than the weight of the inductor 72. Therefore, as shown schematically by the two-dot chain line in Figure 4, when the solders S1 and S2 melt, the inductor 72 falls (separates) from the mounting pads 131 and 132 into the space Sd below due to the weight of the inductor 72. The weight of the inductor 72 is the product of the mass of the inductor 72 and the acceleration of gravity.

[0085] Each of the capacitor 73 and the power transistor 75 is lighter than the inductor 72. Therefore, for example, even when the solders S3 and S4 melt, they can keep the power transistor 75 bonded to the mounting pads 133 and 134. In other words, the weight of the power transistor 75 is smaller than the interfacial tension of the solders S3 and S4.

[0086] In the electrical path between the power supply P and the motor 25, the two external patterns 121 and 122 are connected by the inductor 72 and are not connected in parallel by any other wiring. Furthermore, the electronic board device 62 does not have any other path that bypasses the inductor 72 and electrically connects the power supply P and the motor 25. Therefore, the pattern 82 blocks the current between the power supply P and the motor 25 by moving the inductor 72 away from the mounting pads 131 and 132.

[0087] When the inductor 72 moves away from the mounting pads 131 and 132, the current between the power source P and the motor 25 is interrupted, and the power transistor 75, the inverter circuit 74, and the motor 25 are also interrupted. As a result, the motor 25 stops, and heat generation in the electronic components and wiring also stops. This prevents the electronic board device 62 from being burned due to an overcurrent, for example.

[0088] Terminals 151 and 152 of inductor 72 may come into contact with test pad 138. However, terminals 151 and 152 do not come into contact with test pad 138 and test pad 142, which are spaced apart from each other, at the same time. Therefore, when inductor 72 falls off mounting pads 132 and 133, it is possible to prevent short-circuiting between drive wiring 111 and ground pattern 112. Note that test pads 138 and 142 may be covered with, for example, an insulating seal or coating to prevent short-circuiting.

[0089] 3, the inductor 72 is located upstream of the power transistor 75, the inverter circuit 74, and the motor 25. The pattern 82 cuts off the current at an upstream position, which more reliably prevents the power transistor 75, the inverter circuit 74, and the motor 25 from burning out.

[0090] As described above, the inductor 72 falls off from the mounting pads 131 and 132 when an overcurrent flows through the drive wiring 111. However, the inductor 72, the capacitor 73, the MOSFET of the inverter circuit 74, and the power transistor 75 are mounted on the substrate 71 by ordinary reflow soldering.

[0091] In the brake system 10 according to the first embodiment described above, the outer surface 81a of the insulating material 81 is configured to face a direction other than vertically upward. The power transistor 75 is configured to generate heat when energized and is disposed on the outer surface 81b. The inductor 72 is disposed on the outer surface 81a. The pattern 82 has mounting pads 132 and 133, a via 135, and external patterns 122 and 123. The mounting pad 133 is disposed on the outer surface 81b and is joined to the power transistor 75. The mounting pad 132 is disposed on the outer surface 81a and is joined to the inductor 72 by solder S2. The via 135 penetrates the insulating material 81. The external pattern 123 connects the mounting pad 133 and the via 135. The external pattern 122 connects the mounting pad 132 and the via 135. The pattern 82 is configured so that when the solders S1 and S2 melt, the weight of the inductor 72 separates it from the mounting pad 132, thereby cutting off the current flow to the power transistor 75.

[0092] Therefore, for example, if an overcurrent occurs in the pattern 82, the temperature of the electronic board device 62 rises due to heat generated by the power transistor 75 and the electrical resistance of the external pattern 123, via 135, and external pattern 122. When the temperature of the electronic board device 62 exceeds the melting point of the solders S1 and S2, the solders S1 and S2 melt, and the weight of the inductor 72 separates it from the mounting pad 132. This causes the pattern 82 to cut off current to the power transistor 75. Therefore, the electronic board device 62 can cut off the overcurrent with a simple structure without adding components such as fuses, thereby achieving miniaturization and cost reduction. Between the power transistor 75 and the inductor 72, the overcurrent flows through the external pattern 123, via 135, and external pattern 122. Therefore, heat generated by the electrical resistance of the external pattern 123, via 135, and external pattern 122 raises the temperature of the interior of the electronic board device 62. Therefore, in the electronic board device 62, the solder S1 and S2 can be melted more easily than in a case where the power transistor 75 and the inductor 72 are arranged on the same surface and connected by a single wiring, and thus the overcurrent can be blocked more reliably.

[0093] The insulating material 81 has multiple insulating layers 90 located between two outer surfaces 81a and 81b. The pattern 82 has internal patterns 125 and 126. The internal patterns 125 and 126 are disposed between two adjacent insulating layers 90, connected to vias 135, and overlap with solders S1 and S2 in a direction perpendicular to the outer surface 81b. Therefore, for example, if an overcurrent occurs in the pattern 82, the electrical resistance of the internal patterns 125 and 126 further increases the temperature of the electronic board device 62. Furthermore, because the internal patterns 125 and 126 overlap with the solders S1 and S2, the solders S1 and S2 can be efficiently heated. Therefore, the electronic board device 62 can easily melt the solders S1 and S2, thereby more reliably interrupting the overcurrent.

[0094] The inductor 72 is adjacent to a lower space Sd located below the inductor 72. The inductor 72 is configured so that when the solders S1 and S2 melt, the weight of the inductor 72 causes it to fall off the mounting pad 132 into the lower space Sd. Therefore, as an example, the electronic board device 62 can prevent the inductor 72 from being supported by other components and remaining near the mounting pad 132, thereby more reliably blocking overcurrent.

[0095] The inductor 72 is heavier than the power transistor 75. Therefore, for example, the weight of the inductor 72 is greater, and when the solders S1 and S2 melt, the weight of the inductor 72 can easily separate it from the mounting pad 132. Therefore, the electronic board device 62 can more reliably cut off overcurrent.

[0096] The test pad 138 is provided on the outer surface 81a and is located below the inductor 72. The test pad 142 is provided on the outer surface 81a and is located below the inductor 72, and is configured to have a different potential from the test pad 138. The inductor 72 has terminals 151 and 152. The terminal 152 is joined to the mounting pad 132 by solder S2. The terminal 151 is spaced apart from the terminal 152. The distance between the test pad 138 and the test pad 142 is longer than the distance between the terminals 151 and 152. Therefore, for example, when the inductor 72 falls off the mounting pad 132, the terminals 151 and 152 can prevent the terminals 151 and 152 from coming into contact with the test pad 138 and the test pad 142. In other words, the inductor 72 can prevent the test pad 138 and the test pad 142, which have different potentials, from being short-circuited.

[0097] The motor 25 is electrically connected to the pattern 82. The pressure regulator 26 is provided with a fluid chamber 45 configured to store brake fluid. The pressure regulator 26 is configured to change the pressure in the fluid chamber 45 by being driven by the motor 25. Therefore, as an example, the brake control device 11 can prevent an overcurrent from flowing to the motor 25.

[0098] (Second embodiment) The second embodiment will be described below with reference to Fig. 5. In the following description of the embodiments, components having the same functions as components already described are given the same reference numerals as the components already described, and further description may be omitted. Furthermore, components given the same reference numerals do not necessarily have all the same functions and properties, and may have different functions and properties according to each embodiment.

[0099] 5 is a cross-sectional view schematically showing a part of an electronic board device 62 according to the second embodiment. As shown in FIG. 5, the electronic board device 62 of the second embodiment further includes a guide 201. The guide 201 is located below the inductor 72 and adjacent to the inductor 72.

[0100] The guide 201 is made of an insulating material such as synthetic resin. The guide 201 is, for example, disposed on the outer surface 81a and adhered to the substrate 71. Note that the material of the guide 201 is not limited to this example, and it may be an electronic component mounted on the substrate 71.

[0101] The guide 201 has a slope 201a. The slope 201a is inclined relative to the outer surface 81a. The distance between the slope 201a and the outer surface 81a narrows toward the inductor 72. The guide 201 may have a flat surface or a curved surface.

[0102] 5, when the solders S1 and S2 melt, the inductor 72 falls off (detaches) from the mounting pads 131 and 132 along the slope 201a due to the weight of the inductor 72. The slope 201a pulls the fallen inductor 72 away from the outer surface 81a and the mounting pads 131 and 132 in the thickness direction.

[0103] In the brake system 10 of the second embodiment described above, the inclined surface 201a is located below the inductor 72 and is inclined relative to the outer surface 81a so that the distance between the inclined surface 201a and the outer surface 81a narrows toward the inductor 72. When the solder pieces S1 and S2 melt, the inductor 72 is configured to move away from the mounting pad 132 along the inclined surface 201a due to its own weight. Therefore, for example, the electronic board device 62 can prevent the inductor 72 from being supported by other components and remaining near the mounting pad 132, thereby more reliably interrupting overcurrent. Furthermore, the electronic board device 62 can prevent the inductor 72, which is far from the mounting pad 132, from contacting the outer surface 81a. Therefore, the electronic board device 62 can prevent, for example, electrical connection between the inductor 72 and the mounting pad 132 or another electrode on the outer surface 81a.

[0104] (Third embodiment) The third embodiment will be described below with reference to Fig. 6. Fig. 6 is a cross-sectional view schematically showing a part of an electronic substrate device 62 according to the third embodiment. As shown in Fig. 6, in the third embodiment, the inductor 72 and the power transistor 75 at least partially overlap in the thickness direction.

[0105] In the third embodiment, the entire power transistor 75 overlaps in the thickness direction with the inductor 72. Therefore, when an overcurrent flows through the power transistor 75, the heat of the power transistor 75 is efficiently transferred to the solders S1 and S2.

[0106] In the brake system 10 of the third embodiment described above, the power transistor 75 and the inductor 72 at least partially overlap in a direction perpendicular to the outer surface 81b. Therefore, as an example, the power transistor 75 overlaps with the inductor 72, and therefore can efficiently heat the solders S1 and S2 that join the inductor 72 to the mounting pads 131 and 132. Therefore, the electronic board device 62 can easily melt the solders S1 and S2, and ultimately can more reliably interrupt overcurrent.

[0107] The entire power transistor 75 overlaps the inductor 72 in a direction perpendicular to the outer surface 81b. Therefore, for example, the power transistor 75 can efficiently heat the solders S1 and S2. Therefore, the electronic board device 62 can easily melt the solders S1 and S2, and can more reliably interrupt overcurrent.

[0108] (Fourth embodiment) The fourth embodiment will be described below with reference to FIG. 7. FIG. 7 is a cross-sectional view schematically showing a portion of an electronic board device 62 according to the fourth embodiment. In the fourth embodiment, the solder S2 overlaps the power transistor 75 in the thickness direction. Therefore, when an overcurrent flows through the power transistor 75, the heat of the power transistor 75 is efficiently transferred to the solder S2. Note that the solder S1 may also overlap the power transistor 75 in the thickness direction.

[0109] In the brake system 10 of the fourth embodiment described above, the solder S2 overlaps the power transistor 75 in a direction perpendicular to the outer surface 81b. Therefore, for example, the power transistor 75 can efficiently heat the solder S2. Therefore, the electronic board device 62 can easily melt the solder S2, thereby more reliably interrupting overcurrent. Furthermore, a portion of the power transistor 75 does not need to overlap with the inductor 72. This improves the degree of freedom in arranging the pattern 82.

[0110] As an example, the electronic board device according to at least one embodiment described above includes an insulating material having a first outer surface and a second outer surface located opposite the first outer surface, with the second outer surface facing in a direction other than vertically upward; a pattern configured to generate heat when electricity is passed through it, the pattern including a first electronic component arranged on the first outer surface, a second electronic component arranged on the second outer surface, solder, a terminal provided on the first outer surface and joined to the first electronic component, a pad provided on the second outer surface and joined to the second electronic component by the solder, a via penetrating the insulating material, a first wiring connecting the terminal and the via, and a second wiring connecting the pad and the via, and configured such that when the solder melts, the weight of the second electronic component moves away from the pad, thereby cutting off the flow of electricity to the first electronic component. For example, when an overcurrent occurs in the pattern, the temperature of the electronic board device rises due to heat generated by the first electronic component and the electrical resistance of the via, first wiring, and second wiring. When the temperature of the electronic board device exceeds the melting point of the solder, the solder melts, and the weight of the second electronic component separates it from the pad. This causes the pattern to cut off current to the first electronic component. Therefore, the electronic board device can cut off overcurrent with a simple structure without adding components such as fuses, thereby achieving miniaturization and cost reduction. Between the first and second electronic components, the overcurrent flows through the first wiring, via, and second wiring. Therefore, heat generated by the electrical resistance of the first wiring, via, and second wiring raises the temperature inside the electronic board device. Therefore, the electronic board device can melt the solder more easily and more reliably cut off overcurrent than when the first and second electronic components are arranged on the same surface and connected by a single wiring.

[0111] In the above-described electronic substrate device, for example, the insulating material has multiple insulating layers positioned between the first outer surface and the second outer surface, and the pattern has an internal pattern disposed between two adjacent insulating layers, connected to the via, and overlapping with the solder in a direction perpendicular to the first outer surface. Therefore, for example, when an overcurrent occurs in the pattern, the temperature of the electronic substrate device further increases due to the electrical resistance of the internal pattern. Furthermore, because the internal pattern overlaps with the solder, the solder can be efficiently heated. Therefore, the electronic substrate device can easily melt the solder, thereby more reliably interrupting the overcurrent.

[0112] In the electronic board device, as one example, the second electronic component is adjacent to a lower space located below the second electronic component, and is configured so that when the solder melts, the weight of the second electronic component causes it to fall off the pad into the lower space. Thus, as one example, the electronic board device can prevent the second electronic component from being supported by other components and remaining near the pad, thereby more reliably interrupting overcurrent.

[0113] For example, the electronic board device further includes a slope positioned below the second electronic component and inclined relative to the second outer surface so that the distance between the second electronic component and the second outer surface narrows toward the second electronic component. When the solder melts, the second electronic component moves away from the pad along the slope due to its own weight. Therefore, for example, the electronic board device can prevent the second electronic component from being supported by other components and remaining near the pad, thereby more reliably interrupting overcurrent. Furthermore, the electronic board device can prevent the second electronic component from contacting the second outer surface when it is away from the pad. Therefore, the electronic board device can prevent, for example, electrical connection between the second electronic component and the pad or another electrode on the second outer surface.

[0114] In the electronic board device, for example, the second electronic component is heavier than the first electronic component. Therefore, for example, the weight of the second electronic component is greater, and when the solder melts, the weight of the second electronic component makes it easier to separate from the pad. Therefore, the electronic board device can more reliably interrupt overcurrent.

[0115] As an example, the electronic board device further includes a first electrode provided on the second outer surface and positioned below the second electronic component, and a second electrode provided on the second outer surface and positioned below the second electronic component, configured to have a different potential from the first electrode. The second electronic component has a first component terminal joined to the pad with the solder and a second component terminal spaced apart from the first component terminal, and the distance between the first electrode and the second electrode is longer than the distance between the first component terminal and the second component terminal. Therefore, as an example, when the second electronic component falls off the pad, the first component terminal and the second component terminal can be prevented from contacting the first electrode and the second electrode. In other words, the second electronic component can be prevented from short-circuiting the first electrode and the second electrode, which have different potentials.

[0116] In the electronic board device, for example, the first electronic component and the second electronic component at least partially overlap in a direction perpendicular to the first outer surface. Therefore, for example, the first electronic component overlaps the second electronic component, allowing efficient heating of solder that joins the second electronic component to the pad. Therefore, the electronic board device can easily melt the solder, thereby more reliably interrupting overcurrent.

[0117] In the electronic board device, for example, the entire first electronic component overlaps the second electronic component in a direction perpendicular to the first outer surface. Therefore, for example, the first electronic component can efficiently heat the solder. Therefore, the electronic board device can easily melt the solder and more reliably interrupt overcurrent.

[0118] In the electronic board device, for example, the solder overlaps the first electronic component in a direction perpendicular to the first outer surface. Therefore, for example, the first electronic component can efficiently heat the solder. Therefore, the electronic board device can easily melt the solder, thereby more reliably interrupting overcurrent. Furthermore, a portion of the first electronic component does not need to overlap with the second electronic component. This improves the degree of freedom in pattern arrangement.

[0119] The brake control device according to at least one embodiment described above includes, for example, the electronic board device, an actuator electrically connected to the pattern, and a pressure regulating device provided with a fluid chamber configured to store brake fluid and configured to change the pressure of the fluid chamber by being driven by the actuator. Thus, for example, the brake control device can suppress overcurrent from flowing to the actuator.

[0120] While the embodiments of the present invention have been described above, the above-described embodiments and modifications are merely examples and are not intended to limit the scope of the invention. The above-described embodiments and modifications can be implemented in various other forms, and various omissions, substitutions, combinations, and modifications can be made without departing from the spirit of the invention. Furthermore, the configurations and shapes of each embodiment and each modification can be partially interchanged. [Explanation of symbols]

[0121] 11...brake control device, 25...motor (actuator), 26...pressure regulating device, 62...electronic board device, 72...inductor (second electronic component), 75...power transistor (first electronic component), 81...insulating material, 81a...outer surface (second outer surface), 81b...outer surface (first outer surface), 82...pattern, 90...insulating layer, 122...external pattern (second wiring), 123...external pattern (first wiring), 125, 126...internal pattern, 132...mounting pad (pad), 133...mounting pad (terminal), 135...via, 138...test pad (first electrode), 142...test pad (second electrode), 151...terminal (second component terminal), 152...terminal (first component terminal), S2...solder (brazing), Sd...lower space.

Claims

1. an insulating material having a first outer surface and a second outer surface opposite the first outer surface, the second outer surface facing in a direction other than vertically upward; a first electronic component configured to generate heat when energized and disposed on the first outer surface; a second electronic component disposed on the second outer surface; and Solder and a pattern including a terminal provided on the first outer surface and bonded to the first electronic component, a pad provided on the second outer surface and bonded to the second electronic component by the solder, a via penetrating the insulating material, a first wiring connecting the terminal and the via, and a second wiring connecting the pad and the via, wherein when the solder melts, the weight of the second electronic component separates from the pad, thereby cutting off current to the first electronic component; An electronic board device comprising:

2. the insulating material having a plurality of insulating layers positioned between the first outer surface and the second outer surface; the pattern has an internal pattern provided between two adjacent ones of the plurality of insulating layers, connected to the via, and overlapping with the solder in a direction perpendicular to the first outer surface; The electronic substrate device according to claim 1.

3. the second electronic component is adjacent to a lower space located below the second electronic component, and is configured to fall off the pad into the lower space due to the weight of the second electronic component when the solder melts. The electronic substrate device according to claim 1.

4. a slope located below the second electronic component and inclined relative to the second outer surface so that a distance between the slope and the second outer surface decreases toward the second electronic component; Further comprising: the second electronic component is configured to move away from the pad along the inclined surface due to the weight of the second electronic component when the solder melts; The electronic substrate device according to claim 1.

5. the second electronic component is heavier than the first electronic component; The electronic substrate device according to claim 1.

6. a first electrode provided on the second outer surface and positioned below the second electronic component; a second electrode provided on the second outer surface, positioned below the second electronic component, and configured to have a different potential from the first electrode; Further comprising: the second electronic component has a first component terminal joined to the pad by the solder and a second component terminal spaced apart from the first component terminal; a distance between the first electrode and the second electrode is longer than a distance between the first component terminal and the second component terminal; The electronic substrate device according to claim 1.

7. the first electronic component and the second electronic component at least partially overlap in a direction perpendicular to the first outer surface; The electronic substrate device according to claim 1.

8. the first electronic component entirely overlaps the second electronic component in a direction perpendicular to the first outer surface; The electronic substrate device according to claim 7.

9. The solder overlaps the first electronic component in a direction perpendicular to the first outer surface. The electronic substrate device according to claim 7.

10. an electronic substrate device according to any one of claims 1 to 9; an actuator electrically connected to the pattern; a pressure adjusting device provided with a fluid chamber configured to store brake fluid, and configured to change the pressure of the fluid chamber by being driven by the actuator; A brake control device comprising:

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