Patent Application
20220278587
The present invention relates to an electronic control unit, and more particularly to, an electronic control unit including a connector enabling electrical connection to an external device such as a power supply.
An electronic control unit of an electric power steering or the like generally includes a module including a connector enabling electrical connection to an external device such as a power supply, and a circuit board including various circuits for controlling a control target, converting power, and the like. In some of such electronic control units, there is provided a module where a conductive member connected to the circuit board is integrally molded with the connector, while an electronic component is connected to the conductive member (for example, see PTL1). In a control device described in PTL 1, a conductor module is formed by integrally molding a bus bar (plate-shaped conductive member) and a connector by molding, and connecting an electronic component to the bus bar.
PTL 1: JP 2006-21552 A
In the control device described in PTL 1, a structure for connecting the electronic component to the bus bar is as follows. A hole is formed in the bottom of the conductor module provided with the bus bar, and a terminal of the electronic component is inserted into the hole in the bottom. Further, the terminal of the electronic component inserted into and protruding from the hole is connected to a terminal of the bus bar protruding from the bottom of the conductor module by welding. In such a structure for connecting the electronic component and the bus bar to each other, a lead portion for connecting the electronic component to the bus bar needs to have a certain-degree length, and accordingly, it is necessary to secure a corresponding space for the connection between the electronic component and the bus bar. Therefore, such a module, in which the electronic component is connected to the bus bar integrally molded with the connector, needs to be further downsized.
In particular, as automatic driving technology has recently progressed, redundant systems may be adopted for various systems so that driving can be continued even if a failure occurs in a component. An in-vehicle electronic control unit may also include at least dual control systems, considering that a failure occurs in an electronic component, a wiring is short-circuited, or the like. In this case, electronic components are also at least doubly mounted on a board, and mounting spaces therefor are required accordingly. Meanwhile, in order to secure a space in the interior of a vehicle and because of an increase in the number of components in an engine room, a space in the engine room has becoming small. Therefore, even an electronic control unit adopting redundant systems needs to be downsized.
The present invention has been made in order to solve the above problems, and an object of the present invention is to provide an electronic control unit that can be downsized.
The present application has a plurality of means of solving the above problems; however, according to one of preferred modes of the present invention, an electronic control unit includes: a board module in which an electric circuit is formed on a board; and a connector module in which a conductive wiring structure is held in a base having a plane surface to enable electric connection between the electric circuit of the board module and an external device via the wiring structure. The wiring structure of the connector module has portions exposed toward the plane surface of the base, and the connector module has electronic components bonded to the wiring structure in a state where the electronic components are placed on the plane surface of the base.
According to the present invention, since the electronic components are bonded to the wiring structure in a state where the electronic components are placed on the plane surface of the base of the connector module, only spaces for placing the electronic components are required at the time of bonding the electronic components, and it is not necessary to secure extra spaces for securing bonding portions between the electronic components and the wiring structure. Therefore, downsizing can be achieved.
Other problems, configurations, and effects that are not described above will be apparent from the following description of embodiments.
Hereinafter, an embodiment of an electronic control unit according to the present invention will be described with reference to the drawings. The present embodiment will be described by exemplifying a case where the present invention is applied to an electronic control unit of an electric power steering device.
[One Embodiment] First, a configuration of an electric power steering device including an electronic control unit according to one embodiment of the present invention will be described with reference to
In
For example, the electric power steering device 1 includes: a steering shaft 2 (only a part thereof is illustrated) connected to the steering wheel; a rack (not illustrated) engaged with a pinion (not illustrated) provided at a lower end of the steering shaft 2, covered by a rack housing 4, and elongating in a left-right direction of a vehicle body; and tie rods 3 connected to both ends of the rack, respectively, to steer the wheels in the left-right direction. Rubber boots 5 are provided between the rack housing 4 and the tie rods 3.
The electric power steering device 1 further includes an electric drive device 6 supplementing a steering torque when the steering wheel is operated. For example, the electric drive device 6 includes: an electric motor 10 applying a supplemental steering force to the rack via a gear 7, steering sensors 20 detecting steering angles and steering torques of the steering shaft 2, and an electronic control unit (hereinafter, referred to as ECU) 30 controlling the electric motor 10 based on detection values of the steering sensors 20. The electric motor 10 and the ECU 30 are configured, for example, in an integrally incorporated structure, and the ECU 30 is disposed at an end portion of the electric motor 10 on an opposite side of an output shaft (the gear 7). Note that the steering sensors 20 can be configured separately from the electric drive device 6.
In the electric power steering device 1, when the steering is turned, a turn driving force thereof is transmitted to the left and right tie rods via the steering shaft 2 to steer the left and right wheels. At this time, in the electric drive device 6, the steering sensors 20 detect steering angles and steering torques of the steering shaft 2 as the steering wheel is operated, and the ECU 30 calculates a control amount of the electric motor 10 based on detection values of the steering sensors 20. Based on the control amount of the ECU 30, the electric motor 10 is rotated to drive the steering shaft 2 in the same direction as the operation direction, and the rotation of the electric motor 10 is transmitted to the rack via the gear 7, thereby supplementing the steering torque of the steering wheel.
An electric system configuration of an electric drive device including an electronic control unit according to one embodiment of the present invention will be described with reference to
The electric drive device 6 illustrated in
The electric motor 10 is, for example, a three-phase motor driven by three-phase AC power, and includes: one stator (not illustrated) including a first three-phase winding 11m constituted by a U-phase coil, a V-phase coil, and a W-phase coil and a second three-phase winding 11s similarly constituted by a U-phase coil, a V-phase coil, and a W-phase, and one rotor (not illustrated) including an output shaft rotatably disposed on an inner circumferential side of the stator. The electric motor 10 is configured such that one rotor is rotationally driven by three-phase windings of two systems including the first three-phase winding 11m and the second three-phase winding 11s. The stator including the first and second three-phase windings 11m and 11s and the rotor of the electric motor 10 are accommodated in a motor housing 12, which will be described later (see
A motor rotation angle, which is a rotation angle of the rotor of the electric motor 10, is detected by rotation angle sensors 16m and 16s. The rotation angle sensors are configured as dual sensors including a main sensor 16m and a sub sensor 16s, and each of the two sensors 16m and 16s is configured to detect a motor rotation angle. Both the main sensor 16m and the sub sensor 16s as rotation angle sensors output detection signals for the motor rotation angles to both dual control systems of the ECU 30, respectively. In the present embodiment, the rotation angle sensors 16m and 16s are mounted on a board 51 of a board module 50 of the ECU 30, which will be described later (see
The ECU 30 controls the driving of the electric motor 10 including two sets of three-phase windings 11m and 11s, and includes redundant systems controlling the respective three-phase windings. That is, an electronic circuit of the ECU 30 includes two systems including a first control system independently controlling the first three-phase winding 11m and a second control system independently controlling the second three-phase winding 11s. The first control system and the second control system have substantially the same electrical configuration. In the following description, m will be added to the end of a reference numeral for a part corresponding to the first control system, and s will be added to the end of a reference numeral for a part corresponding to the second control system. However, m and s may be omitted if necessary.
Electric circuits of the first control system and the second control system of the ECU 30 include power conversion circuit units 60m and 60s controlling the driving of the electric motor 10, control circuit units 70m and 70s controlling the power conversion circuit units 60m and 60s, and power supply circuit units 90m and 90s connected to power supplies (batteries B) to supply power from the power supplies to the power conversion circuit units 60m and 60s and the control circuit units 70m and 70s, respectively.
The power conversion circuit units 60m and 60s include inverter circuits 61m and 61s converting currents supplied from the power supplies from DC currents to three-phase AC currents to supply the converted currents to the three-phase windings 11m and 11s, and current sensors 65m and 65s provided between the inverter circuits 61m and 61s and the ground to each detect a value of a motor current flowing through the electric motor 10. The inverter circuits 61m and 61s include three-phase bridge circuits including high-side switching elements and low-side switching elements (a total of six switching elements 62m or 62s in each of the systems) for supplying the current to the U-phase coil, the V-phase coil, and the W-phase coil of the electric motor 10, respectively, and switching elements 63m and 63s for motor relays capable of cutting off the current to the respective-phase coils (three in total in each of the systems) (see FIG. to be described later). Each switching element is constituted by, for example, an FET. The current sensors 65m and 65s are so-called shunt resistors, each being configured to detect a motor current value based on a potential difference between both ends of the shunt resistor. The current sensors 65m and 65s of the respective systems output motor current value detection signals to MCUs 71m and 71s, which will be described later, of the corresponding systems.
The control circuit units 70m and 70s include MCUs 71m and 71s receiving output signals from the various sensors to perform calculations for assistance control in supplementing a steering torque of the steering wheel, control a motor current, and the like, pre-drivers 72m and 72s that are integrated circuits (ICs) driving the inverter circuits 61m and 61s based on command signals from the MCUs 71m and 71s, and relay drivers 73m and 73s that are integrated circuits (ICs) driving reverse connection protection circuits 91m and 91s, which will be described later, based on command signals from the MCUs 71m and 71s. The MCUs 71m and 71s include microcomputers 77, oscillators 78, memories 79, etc. (see
In addition, the control circuit units 70m and 70s include power supply ICs 74m and 74s generating power required for driving the ECU 30, and CAN drivers 75m and 75s enabling communication with an external ECU via CAN. When a turn-on signal of an ignition switch is input, the power supply ICs 74m and 74s are activated to appropriately lower power from the batteries B and supply the appropriately lowered power to the MCUs 71m and 71s, the rotation angle sensors, and the steering sensors 20. The CAN is for performing bidirectional communication using two communication lines called CANH and CANL. The CAN drivers 75m and 75s receive, for example, vehicle speed signals and the like via the CAN, and input the vehicle speed signals and the like to the MCUs 71m and 71s. The two communication lines of the CAN and the signal line of the ignition switch can be connected via first connector units 84m and 84s of a connector module 80, which will be described later.
The power supply circuit units 90m and 90s include reverse connection protection circuits 91m and 91s provided between the power supplies (batteries B) and the inverter circuits 61m and 61s, and filter circuits 95m and 95s provided between the reverse connection protection circuits 91m and 91s and the inverter circuits 61m and 61s.
As illustrated in
The filter circuit 95 includes, for example, a coil 96 disposed between the reverse connection protection circuit 91 and the inverter circuit 61, and a first capacitor 97 and a second capacitor 98 connecting both ends of the coil 96, respectively, to the ground. The filter circuit 95 suppresses emission of noise generated by the operation of the switching element of the power conversion circuit unit 60 to the power supply, and suppresses noise of power flowing from the power supply to the power conversion circuit unit 60.
As illustrated in
The first and second sensors 21m, 22m, 21s, and 22s as steering angle sensors corresponding to the respective systems can be electrically connected to the MCUs 71m and 71s, and output steering angle detection signals to the MCUs 71m and 71s. The first and second sensors 23m, 24m, 23s, and 24s as torque sensors corresponding to the respective systems can be electrically connected to the MCUs 71m and 71s, respectively, and output steering torque detection signals to the MCUs 71m and 71s, respectively.
Various electronic components, power supply lines, control lines, and signal lines constituting the electric circuits of the first control system and the second control system described above constitute an electronic component assembly 32, which will be described later.
More specifically, the power conversion circuit units 60m and 60s and the control circuit units 70m and 70s constitute the board module 50, which will be described later, and the power supply circuit units 90m and 90s constitute the connector module 80, which will be described later.
A structure of an electric drive device including an electronic control unit according to one embodiment of the present invention will be described with reference to FIGS. and 5.
In
As illustrated in
The mounting base 31 is formed to have a substantially circular shape when viewed in the axial direction of the motor housing 12 according to the cylindrical shape of the motor housing 12. The mounting base 31 has a plurality of mounting supports 41 for mounting the electronic component assembly 32 thereon. For example, three mounting supports are disposed at equal intervals along an outer circumferential portion of the mounting base 31. Each of the mounting supports 41 has a screw hole 41a.
The mounting base 31 is made of a metal to have a heat sink function to dissipate heat generated from a plurality of electronic components constituting the electronic component assembly 32, and has a plurality of protrusions 42 contacting the electronic component assembly 32. For example, the protrusions 42 are provided at positions corresponding to the arrangement of the electronic components constituting the power conversion circuit units 60m and 60s illustrated in
A first caulking recess 45 for caulking the cover 33 is formed in the outer circumferential surface of the mounting base 31 at a portion lower than the annular groove 43. A second caulking recess 46 for caulking the cover 33 is formed in the outer circumferential surface of the mounting base 31 at a portion higher than the annular groove 43 and different in a circumferential direction from the first caulking recess 45.
The electronic component assembly 32 realizes the electric circuits of the first control system and the second control system illustrated in
The connector module 80 has an annular groove 82a for disposing the first seal member 35 therein. Configurations and structures of the board module 50 and the connector module 80 will be described in detail later.
The cover 33 is formed of, for example, a metal, such as an aluminum alloy or iron, or a resin in the form of a cylinder having a bottom with one side opened. A bottom portion 33b of the cover 33 has an opening 33c for exposing the first connector units 84 and the second connector units 85 of the connector module 80 to the outside. The cover 33 is fixed to the mounting base 31 by caulking an outer circumferential portion of a cylindrical portion 33a at positions corresponding to the first caulking recess 45 and the second caulking recess 46 of the mounting base 31 (see white arrows in
As a result, the cover 33 can be fixed to the mounting base 31 without using a fastening member. Therefore, it is not necessary to secure a space for placing a fastening member for the cover 33, and it is possible to secure an area for mounting the electronic components of the electronic component assembly 32 accordingly. In addition, the first seal member 35 can seal a gap between a surface of the connector module 80 on a side where the first connector units and the second connector units 85 are placed and the bottom surface of the cover 33, and the second seal member 36 can seal a gap between the outer circumferential surface of the mounting base 31 and an inner circumferential surface of the cylindrical portion 33a of the cover 33.
Next, a structure of a board module constituting an electronic control unit according to one embodiment of the present invention will be described with reference to FIGS. and 6.
In the board module 50, the power conversion circuit units 60m and 60s and the control circuit units 70m and 70s of the two systems illustrated in
The board 51 is made of, for example, a non-metallic base material such as an epoxy resin base material. The board 51 has first connection portions 52m and 52s for connection to the end portions of the first and second three-phase windings 11m and 11s (see
The various electronic components of the power conversion circuit units 60m and 60s and the control circuit units 70m and 70s of the two systems are disposed closer to an inner circumference than the first connection portions 52m and 52s to the sixth connection portions 57m and 57s. The various electronic components constituting the power conversion circuit unit 60m and the control circuit unit 70m of the first control system are disposed on one side (upper side in
Specifically, among the electronic components constituting the power conversion circuit units 60m and 60s of the respective systems, the respective three switching elements 63m and 63s for the motor relays of the inverter circuits 61m and 61s are disposed adjacent to the first connection portions 52m and 52s in the extending direction of the center line C1 while being closer to the center than the first connection portions 52m and 52s, and are arranged side by side in the direction orthogonal to the center line C1. Also, the switching elements 62m and 62s for the three-phase bridge circuits of the inverter circuits 61m and 61s are disposed adjacent to the switching elements 63m and 63s for the motor relays in the extending direction of the center line C1 while being closer to the center than the switching elements 63m and 63s for the motor relays, and are arranged side by side in the direction orthogonal to the center line C1. Here, concerning the switching elements 62m and 62s for the three-phase bridge circuits, two elements including a high-side switching element and a low-side switching element are configured as one package. The current sensors 65m and 65s of the power conversion circuit units 60m and 60s are disposed closer to the outer circumference than the switching elements 62m and 62s for the three-phase bridge circuits in the direction orthogonal to the center line C1.
In addition, among the electronic components constituting the control circuit units 70m and 70s of the respective systems, the microcomputers 77m and 77s, the oscillators 78m and 78s, and the memories 79m and 79s constituting the MCUs 71m and 71s are disposed at positions far away from the switching elements 62m and 62s for the three-phase bridge circuits in the extending direction of the center line C1 and away from the center line C1. The pre-drivers 72m and 72s are disposed closer to the switching elements 62m and 62s for the three-phase bridge circuits than the MCUs 71m and 71s in the extending direction of the center line C1, and closer to the circumference than the MCUs 71m and 71s and the switching elements 62m and 62s for the three-phase bridge circuits. The power supply ICs 74m and 74s are disposed on a surface of the board opposite to the surface on which the MCUs 71m and 71s and the pre-drivers 72m and 72s are mounted. Capacitors 74a for input to the power supply ICs 74m and 74s are mounted on the board 51.
The rotation angle sensors 16m and 16s are mounted at a central portion of the board 51, that is, at a position on an extension line of the output shaft of the electric motor 10. One of the motor rotation angle sensors 16m and 16s of the two systems is disposed on the surface of the board on which the above-described various electronic components are mounted, and the other one is disposed on the surface of the board on which the power supply ICs 74m and 74s are mounted.
A structure of a connector module of an electronic control unit according to one embodiment of the present invention will be described with reference to
Briefly, in the connector module 80, two sets of first connector units 84m and 84s and second connector units 85m and 85s corresponding to the first control system and the second control system that are redundant-system electric circuits as illustrated in
Specifically, in
The connector base 81 is made of, for example, a synthetic resin, and is formed in a substantially circular shape as illustrated in
The first connector units 84m and 84s of the respective systems are parts having a function as connectors enabling electrical connection to the power supplies and enabling electrical connection to the CAN and the ignition switch, each accommodating two connector terminals 101a and 105a connected to a positive electrode side and a ground side of the power supply and three connector terminals 109a connected to the CAN and the ignition switch, which will be described later. The two connector terminals 101a and 105a for the power supply are, for example, plate-like, and face each other side by side in the extending direction of the center line C2. The three connector terminals 109a are, for example, rod-like, and are positioned closer to the center line C2 than the two connector terminals 101a and 105a while being arranged side by side in the extending direction of the center line C2.
The second connector units 85m and 85s of the respective systems are parts having a function as connectors enabling electrical connection to the steering sensors 20, each accommodating six connector terminals 110a, which will be described later. The six connector terminals 110a are, for example, rod-like, and arranged side by side in the direction orthogonal to the center line C2.
The first connector unit 84m and the second connector unit 85m of the first control system and the first connector unit 84s and the second connector unit 85s of the second control system are arranged to be substantially line-symmetric about the center line C2. The first connector units 84m and 84s are disposed at a substantially central portion of the first surface 82 of the connector base 81 in the extending direction of the center line C2. The second connector units 85m and 85s are adjacent to the first connector units 84m and 84s in the extending direction of the center line C2, and are located opposite to the notch 81a. That is, the second connector units 85m and 85s are disposed at positions corresponding to regions where the control circuit units 70m and 70s of the board module 50 are disposed, rather than regions where the power conversion circuit units 60m and 60s of the board module 50 are disposed. As a result, signal lines connecting the second connector units 85m and 85s and the control circuit units 70m and 70s can be shortened.
As illustrated in
The first relay 92m, the second relay 93m, the coil 96m, the first capacitor 97m, and the second capacitor 98m constituting the power supply circuit unit 90m of the first control system, and the first relay 92s, the second relay 93s, the coil 96s, the first capacitor 97s, and the second capacitor 98s constituting the second control system are arranged to be substantially line-symmetric about the center line C2. The various electronic components constituting the power supply circuit units 90m and 90s of the respective systems are arranged such that lengths of wirings of wiring structures 100m and 100s for connecting the electronic components to each other, which will be described later, are as short as possible. This will be described in detail below.
The first relays 92m and 92s are close to the positions of the first connector units 84m and 84s, and are disposed at positions closer to the opposite side of the notch 81a than the central portion in the extending direction of the center line C2. The first relays 92m and 92s are disposed such that sources S and gates G are located closer to the outer circumference than drains D in the direction orthogonal to the center line C2.
The second relays 93m and 93s are disposed in an outer circumferential end portion closer to the outer circumference than the first relays 92m and 92s in the direction orthogonal to the center line C2. The second relays 93m and 93s are disposed such that drains D are located closer to the notch 81a than sources S and gates G in the extending direction of the center line C2. The sources S and the gates G of the second relays 93m and 93s are close to the sources S and the gates G of the first relays 92m and 92s.
The first capacitors 97m and 97s are disposed closer to the notch 81a than the second relays 93m and 93s in the extending direction of the center line C2.
The coils 96m and 96s are disposed in the vicinity of the center line C2 and in the vicinity of the notch 81a (an outer circumferential portion on one side in the extending direction of the center line C2), and are far away from the second relays 93m and 93s and the first capacitors 97m and 97s.
The second capacitors 98m and 98s are adjacent to the coils 96m and 96s and the first capacitors 97m and 97s, and are disposed closer to the outer circumference than the coils 96m and 96s and closer to the inner circumference than the first capacitors 97m and 97s in the direction orthogonal to the center line C2.
As illustrated in
Each of the wiring structures 100m and 100s of the two systems include three ninth wirings 109 constituting signal lines for connecting two signal lines (CANH and CANL) of the CAN and a signal line of the ignition switch illustrated in
The first wirings 101 to the tenth wirings 110 constituting the wiring structures 100m and 100s of the two systems are insert-molded and integrated with the connector base 81.
The wiring structure 100m of the first control system and the wiring structure 100s of the second control system are arranged to be substantially line-symmetric about the center line C2. However, since the sources S and the gates G of the first relays 92m and 92s and the second relays 93m and 93s of the two systems cannot be positioned line-symmetrically, the arrangement is partially different. The first wiring 101 to the fourth wiring 104 constituting the positive electrode-side power supply lines of the respective systems are configured to be as short as possible while securing lengths for connecting the first relays 92m and 92s, the second relays 93m and 93s, the coils 96m and 96s, the first capacitors 97m and 97s, and the second capacitors 98m and 98s. This is intended to reduce resistances of the power supply lines themselves. Further, portions connected to the board module 50 in the positive electrode-side and ground-side power supply lines are disposed close to the outer circumference of the connector base 81. This is intended to prevent the portions connected to the board module 50 in the power supply lines from obstructing the arrangement of the electronic components to be mounted on the connector base 81, and from obstructing the movement of inspection devices when the electronic components mounted on the connector base 81 are inspected.
Briefly, as illustrated in
This will be described in detail below.
As illustrated in
The second wirings 102 are plate-like conductive members for connecting the sources S of the first relays 92m and 92s and the sources S of the second relays 93m and 93s. The second wirings 102 are disposed closer to the outer circumference than the first wirings 101 in the direction orthogonal to the center line C2, and extends toward the outer circumference in the direction orthogonal to the center line C2. The second wirings 102 are embedded in the connector base 81. The second wirings 102 are bonded to the sources S of the first relays 92m and 92s and the sources S of the second relays 93m and 93s, respectively, via solder (see
The third wirings 103, which are conductive members for connecting the drains D of the second relays 93m and 93s, one ends of the coils 96m and 96s, and the positive electrode sides of the first capacitors 97m and 97s, are embedded in the connector base 81. The third wirings 103 include plate-shaped first embedded parts 103a positioned closer to the notch 81a than the second wirings 102 at outer circumferential end portions in the direction orthogonal to the center line C2, plate-shaped second embedded parts 103b adjacent to center line C2 while being closer to the notch 81a than the ninth wirings 109, and third embedded parts 103c connecting the first embedded part 103a and the second embedded part 103b to each other. The third wirings 103 are bonded to the drains D of the second relays 93m and 93s and the positive electrode sides of the first capacitors 97m and 97s, respectively, via solder (see
The fourth wirings 104 are conductive members for connecting the other ends of the coils 96m and 96s and the positive electrode sides of the second capacitors 98m and 98s. The fourth wirings 104 has plate-shaped embedded parts embedded in the connector base 81 and extending from the vicinity of the center line C2 to outer circumferential end portions of the connector base 81 in the direction orthogonal to the center line C2 at an outer circumferential end portion of the connector base 81 close to the notch 81a in the extending direction of the center line C2, and include plate-shaped positive electrode-side connection portions 104a bent from outer peripheral end portions of the embedded parts and protruding toward the board module 50 from the second surface of the connector base 81 for connection to the power conversion circuit units 60m and 60s of the board module 50. The embedded parts of the fourth wirings 104 are bonded to the other end portions of the coils 96m and 96s via solder by forming seventh recesses 127 (see
The fifth wirings 105, which are conductive members for connecting the ground sides of the first capacitors 97m and 97s and the ground sides of the second capacitors 98m and 98s to the ground sides of the power supply lines, are disposed to correspond to the positions of the first connector units 84. Since the fifth wirings 105 are ground-side power supply lines connected only to the first capacitors 97m and 97s and the second capacitors 98m and 98s, among the electronic components constituting the power supply circuit units, they are configured to be as short as possible in order to reduce resistance. Specifically, the fifth wirings 105 have plate-shaped embedded parts embedded in the connector base 81 and expanding from the positions corresponding to the first connector units 84 to the outer circumferential end portions in the direction orthogonal to the center line C2, and include plate-shaped ground-side connector terminals 105a bent from one side end portions of the embedded parts and protruding from the first surface 82 of the connector base 81 into the first connector units 84 to enable connection to the ground sides of the power supplies, and plate-shaped ground-side connector portions 105b bent from the other side end portions of the embedded parts and protruding from the second surface 83 of the connector base 81 toward the board module 50 for connection to the power conversion circuit units 60m and 60s of the board module 50. The embedded parts of the fifth wirings 105 are bonded to the ground sides of the second capacitors 98m and 98s via solder by forming ninth recesses 129 (see
The sixth wiring 106m and the seventh wiring 107m of the first control system are conductive members for connecting the gate G of the first relay 92m to the relay driver 73m of the control circuit unit 70m. The sixth wiring 106m and the seventh wiring 107m are disposed on both sides with the second wiring 102 interposed therebetween in the extending direction of the center line C2. The sixth wiring 106m is embedded in the connector base 81, and is bonded to the gate G of the first relay 92m and a jumper member (conductive member) 111m via solder by forming an eleventh recess 131m (see
The eighth wiring 108m of the first control system is a conductive member for connecting the gate G of the second relay 93m to the relay driver 73m of the control circuit unit 70m. The eighth wiring 108m is disposed closer to the outer circumference than the second wiring 102 in the direction orthogonal to the center line C2. The eighth wiring 108m is embedded in the connector base 81, and is bonded to the gate G of the second relay 93m via solder by forming a thirteenth recess 133m (see
The sixth wiring 106s of the second control system is a conductive member for connecting the gate G of the first relay 92s to the relay driver 73s of the control circuit unit 70s. The sixth wiring 106s has an embedded part embedded in the connector base 81 and extending toward the outer circumference, and has a first switching control connection portion 106a in a rod shape bent from the embedded part and protruding from the second surface 83 of the connector base 81 toward the board module 50 for connection to the control circuit unit 70s.
The seventh wiring 107s and the eighth wiring 108s of the second control system are conductive members for connecting the gate G of the second relay 93s to the relay driver 73s of the control circuit unit 70s. The seventh wiring 107s and the eighth wiring 108s disposed on both sides with the second wiring 102 interposed therebetween in the extending direction of the center line C2. The seventh wiring 107s is embedded in the connector base 81. The seventh wiring 107s is bonded to the gate G of the second relay 93s and a jumper member (conductive member) 111s via solder by forming a twelfth recess 132s (see
The plate-shaped embedded parts of the first wirings 101 to the eighth wirings 108m and 108s are disposed at the same depth from the second surface 83 of the connector base 81. That is, the plurality of first wirings 101 to eighth wirings 108m and 108s embedded in the connector base 81 are formed in a single-layer structure, rather than in a multi-layer structure.
The plurality of ninth wirings 109 have a plurality of (three) rod-shaped connector-side terminals 109a protruding from the first surface 82 of the connector base 81 into the first connector unit 84 to enable connection to the (two) communication lines (CANH and CANL) of the CAN and the (one) signal line of the ignition switch, and rod-shaped board-side connection portions 109b in the same number protruding from the second surface 83 of the connector base 81 toward the board module 50 for connection to the control circuit unit 70 of the board module 50, while the embedded parts embedded in the connector base 81 extend from the connector-side terminals 109a to the board-side connection portions 109b. The three connector-side terminals 109a of the ninth wirings 109 are located closer to the center line C2 than the positive electrode-side connector terminal 101a of the first wiring 101 and the ground-side connector terminal 105a of the fifth wiring 105, and are arranged side by side in the direction parallel to the extending direction of the center line C2. The three board-side connection portions 109b of the ninth wirings 109 are arranged side by side along the outer circumferential portion on the opposite side of the notch 81a in the vicinity of the center line C2. The three embedded parts of the ninth wirings 109 extend along the extending direction of the center line C2 by shifting a direction in which connector-side portions approach the center line C2 in the direction orthogonal to the center line C2. As a result, the ninth wirings 109 can be connected to the control circuit units 70 of the board module 50 without obstructing the arrangement of the first wirings 101 to the eighth wirings 108m and 108s.
The plurality of tenth wirings 110 have a plurality of rod-shaped connector-side terminals 110a (six terminals in the drawing) protruding from the first surface 82 of the connector base 81 into the second connector units 85 to enable connection to the signal lines of the steering sensors 20, and rod-shaped board-side connection portions 110b in the same number protruding from the second surface 83 of the connector base 81 toward the board module 50 for connection to the control circuit units 70 of the board module 50, while the embedded parts embedded in the connector base 81 extend from the connector-side terminals 110a to the board-side connection portions 110b. The six connector-side terminals 110a of the tenth wirings 110 are arranged side by side in the direction orthogonal to the center line C2. The six board-side connection portions 110b of the tenth wirings 110 are arranged side by side along the outer circumferential portion on the opposite side of the notch 81a The six embedded parts of the ninth wirings 109 are arranged side by side to be closer to the outer circumference than the three embedded parts of the ninth wirings 109 in the direction orthogonal to the center line C2, and extend along the extending direction of the center line C2. As a result, the tenth wirings 110 can be connected to the control circuit units 70 of the board module 50 without obstructing the arrangement of the first wirings 101 to the ninth wirings 109.
A groove 140 (see
As illustrated in
A plurality of protrusions 150 are provided on the second surface 83 of the connector base 81 around locations where various electronic components constituting the power supply circuit units 90m and 90s of the first control system and the second control system are placed (see
The plurality of protrusions 150 restrict the movement of the various electronic components when the various electronic components are bonded to the wiring structures by melted solder. This will be described in detail below.
As illustrated in
As illustrated in
The connector module 80 is disposed such that the second surface 83 (the surface on which the electronic components are mounted) of the connector base 81 faces the board module 50. As illustrated in
Next, a method for mounting an electronic component on a connector module constituting an electronic control unit according to one embodiment of the present invention will be described in comparison with a general method for mounting an electronic component on a board.
First, a general method of surface-mounting an electronic component on a board will be described with reference to
First, a printed circuit board is covered with a metal mask, and solder cream is printed on the printed circuit board using a printer. At this time, a thickness of the solder cream is about 150 μm. Next, an electronic component is placed on the printed circuit board on which the solder cream is printed using a machine called a chip mounter. Thereafter, the printed circuit board on which the electronic component is placed is introduced into a reflow furnace to heat and melt the solder, thereby bonding the electronic component to the printed circuit board.
Next, a method of mounting an electronic component on a connector module in which a wiring structure is insert-molded in a connector base according to the present embodiment will be described with reference to
The wiring structure 100 insert-molded in the connector base 81 is exposed toward the second surface 83 through the recess 120 (recesses 121 to 133 illustrated in
Since a surface of the wiring structure 100 correspond to a bottom surface of the recess 120, the recess 120 is filled with solder cream S up to a position where the electronic component can be supported. That is, the solder cream S is filled in the recess 120 at a height of about 600 μm. This is about four times the thickness of solder cream in the general board surface mounting. In this case, it is difficult to print the solder cream using the metal mask.
Next, an electronic component is placed on the recess 120 filled with the solder cream S in the second surface 83 of the connector base 81 using a machine called a chip mounter. Thereafter, the connector base 81 on which the electronic component is placed is introduced into a reflow furnace to heat and melt the solder paste S, thereby bonding electrodes of the electronic component to the wiring structure 100. These steps are similar to those in the general method of surface-mounting the electronic component.
Meanwhile, there is concern that when the solder cream S is melted by being heated in the reflow furnace, the solder cream S filled in the recess 120 to have a height of about 600 μm may leak from the recess 120. However, even if the solder paste S leaks from any of the recesses 120, the leaking melted solder flows into the groove 140 provided between the recesses 120, so that the leaking melted solder can be prevented from entering another one of the recesses 120, thereby preventing the wiring structures 100 from being short-circuited. When the solder cream is melted, the electronic component placed on the second surface 83 of the connector base 81 may be displaced. However, the protrusions 150 protruding from the second surface 83 of the connector base 81 can suppress positional displacement (movement) of the electronic component.
An electronic control unit according to one embodiment of the present invention described above includes: a board module 50 in which an electric circuit is formed on a board 51; and a connector module 80 in which a conductive wiring structure 100 is held in a connector base (base) 81 having a second surface (plane surface) 83 to enable electric connection between the electric circuit of the board module 50 and an external device via the wiring structure 100. The wiring structure 100 of the connector module 80 has portions exposed toward the second surface (plane surface) 83 of the connector base (base) 81, and the connector module 80 has electronic components 92, 93, 96, 97, and 98 bonded to the wiring structure 100 in a state where they are placed on the second surface (plane surface) 83 of the connector base (base) 81.
According to this configuration, since the electronic components 92, 93, 96, 97, and 98 are bonded to the wiring structure 100 in a state where the electronic components 92, 93, 96, 97, and 98 are placed on the second surface (plane surface) 83 of the connector base (base) 81 of the connector module 80, only spaces for placing the electronic components 92, 93, 96, 97, and 98 are required at the time of bonding the electronic components 92, 93, 96, 97, and 98, and it is not necessary to secure extra spaces for securing bonding portions between the electronic components 92, 93, 96, 97, and 98 and the wiring structure 100. Therefore, the ECU 30 can be downsized.
In the electronic control unit according to the present embodiment, the wiring structure 100 includes embedded parts embedded in the connector base (base) 81, and the embedded parts of the wiring structure 100 are configured such that only portions bonded to the electronic components 92, 93, 96, 97, and 98 are exposed toward the second surface (plane surface) 83 of the connector base (base) 81. According to this configuration, the connector base (base) 81 can reliably hold the wiring structure 100.
In the electronic control unit according to the present embodiment, the electronic components 92, 93, 96, 97, and 98 are configured as leadless components. According to this configuration, since the electronic components 92, 93, 96, 97, and 98 have no lead length, they can be bonded to the wiring structure 100 without having to secure extra spaces, thereby downsizing the ECU 30.
In the electronic control unit according to the present embodiment, the electronic components 92, 93, 96, 97, and 98 are bonded to the wiring structure 100 via solder S. According to this configuration, as a method of bonding the electronic components 92, 93, 96, 97, and 98 to the wiring structure 100 held in a state where it is exposed toward the second surface (plane surface) 83 of the connector base (base) 81, a method similar to surface-mounting of electronic components on a printed circuit board can be adopted.
In the electronic control unit according to the present embodiment, the connector base (base) 81 has a plurality of protrusions 150 (151 to 154) protruding from the second surface (plane surface) 83 around positions at which the electronic components 92, 93, 96, 97, and 98 are placed on the second surface (plane surface) 83 to restrict the movement of the electronic components 92, 93, 96, 97, and 98. According to this configuration, at the time of bonding the electronic components 92, 93, 96, 97, and 98 via metal cream such as solder, the movement of the electronic components 92, 93, 96, 97, and 98 can be restricted when the metal cream is melted. In the electronic control unit according to the present embodiment, the wiring structure 100 includes a plurality of wirings 101 to 110, the plurality of wirings 101 to 110 include respective embedded parts embedded in the base, the connector base (base) 81 has a plurality of recesses 120 (121 to 133) exposing the embedded parts of the plurality of wirings 101 to 110 toward the second surface (plane surface) 83, and the connector base (base) 81 has a groove 140 (141 to 144) between recesses through which the wirings 101 to 110 having different potentials are exposed among the plurality of recesses 120 (121 to 133). According to this configuration, when the recesses 120 (121 to 133) are filled with metal cream such as solder to bond the electronic components 92, 93, 96, 97, and 98 to the wiring structure 100, even if the melted metal cream leaks from any of the recesses 120, the melted metal cream flows into the groove 140, so that the metal cream leaking from the recess 120 can be prevented from entering another one of the recesses 120, thereby preventing the wiring structure 100 from being short-circuited.
In the electronic control unit according to the present embodiment, the wiring structure 100 includes embedded parts embedded in the connector base (base) 81, and the embedded parts of the wiring structure 100 are disposed at positions of the same depth from the second surface (plane surface) 83 of the connector base (base) 81 in a single-layer structure. According to this configuration, the electronic components 92, 93, 96, 97, and 98 can be easily placed on the second surface (plane surface) 83 of the connector base (base) 81.
In the electronic control unit according to the present embodiment, the connector module 80 is disposed such that the second surface (plane surface) 83 of the connector base (base) 81 faces the board module 50. According to this configuration, the board module 50 and the connector module 80 can be compactly accommodated.
In the electronic control unit according to the present embodiment, the connector module 80 enables electrical connection to a power supply, the board module 50 is provided with a power conversion circuit unit 60 and a control circuit unit 70 on the board 51, the power conversion circuit unit 60 converting power supplied from the power supply via the connector module 80 and the control circuit unit 70 controlling driving of the power conversion circuit unit 60, the power conversion circuit unit 60 is disposed on one side of the board 51, and the control circuit unit 70 is disposed on the other side of the board 51.
According to this configuration, since the power conversion circuit unit 60 and the control circuit unit 70 are provided on the same board 51, it is possible to reduce the size in comparison with a configuration in which the power conversion circuit unit and the control circuit unit are arranged on different boards.
In the electronic control unit according to the present embodiment, the connector module 80 enables electrical connection to a power supply, the board module 50 is provided with a power conversion circuit unit 60 and a control circuit unit 70 on the board 51, the power conversion circuit unit 60 converting power supplied from the power supply via the connector module 80 and the control circuit unit 70 controlling driving of the power conversion circuit unit 60, and the electronic components include switching elements 92 and 93 that cut off a current in a case where the power supply is connected to have a reverse polarity or in a case where a short circuit occurs in the power supply. According to this configuration, a power supply line connecting the power supply and the power conversion circuit unit 60 can be efficiently disposed.
In the electronic control unit according to the present embodiment, the wiring structure 100 includes control wirings 106, 107, and 108 functioning as control lines for controlling the switching elements, the control wirings 106, 107, and 108 have connection portions 106a, 107a, and 108a protruding from the connector base (base) 81 toward the board module 50 for connection to the control circuit unit 70 of the board module 50, and the connection portions 106a, 107a, and 108a of the control wirings 106, 107, and 108 are located at an outer circumferential portion of the connector base (base) 81.
According to this configuration, the connection portions 106a, 107a, and 108a can be connected to the board module 50 without obstructing the arrangement of the electronic components.
In the electronic control unit according to the present embodiment, the electronic components further include filter elements 96, 97, and 98 constituting a filter circuit that suppresses noise of power flowing to the power conversion circuit unit, and the filter elements 96, 97, and 98 are disposed closer to the power conversion circuit unit 60 than the switching elements 92 and 93. According to this configuration, according to this configuration, a power supply line connecting the power supply and the power conversion circuit unit 60 can be efficiently disposed.
In the electronic control unit according to the present embodiment, the power conversion circuit unit 60 of the board module 50 converts DC power supplied from the power supply into AC power, and the board module 50 supplies the AC power converted by the power conversion circuit unit 60 to the outside without passing through another board module other than the board module 50. According to this configuration, when AC power is supplied from the power conversion circuit unit 60 to the outside, other board modules are unnecessary, and accordingly, downsizing can be achieved.
The electronic control unit according to the present embodiment further includes a mounting base 31 on which the board module 50 and the connector module 80 are mounted, the board module 50 and the connector module 80 are stacked on the mounting base 31 in this order, and the board module 50 is fixed by sandwiching the board 51 between the mounting base 31 and the connector module 80. According to this configuration, it is not necessary to mount the board module 50 and the connector module 80 on separate mounting bases 31, and the number of fastening members can be reduced accordingly. As such a fastening member is not necessary, the board module 50 can secure a space for mounting electronic components, thereby efficiently arranging the electronic components.
In the electronic control unit according to the present embodiment, the mounting base 31 has a plurality of mounting supports 41 supporting the board module 50 and the connector module 80, the connector module 80 has a plurality of mounting support columns 86 erected at positions corresponding to the plurality of mounting supports 41 of the mounting base 31, respectively, each of the plurality of mounting support columns 86 includes a cylindrical support main body 87 integrated with the connector base (base) 81 and a metal bush 88 integrally molded inside the support main body 87, the bush 88 has a cylindrical portion 88a located on an inner circumferential side of the support main body 87 and an annular flange portion 88b protruding from a distal end of the cylindrical portion 88a toward an outer circumference, and the flange portion 88b of the bush 88 abuts on the board 51 of the board module 50. According to this configuration, the flange portion 88b of the bush 88 surface-contacts the surface of the board 51 of the board module 50 to exhibit a function as a washer, thereby preventing the board 51 of the board module 50 from being damaged.
In the electronic control unit according to the present embodiment, the wiring structure 100 includes a plurality of wirings 101 to 110, the connector module 80 further includes a conductive jumper member 111 bonded to the wiring structure 100 in a state where it is placed on the second surface (plane surface) 83 of the connector base (base) 81, and the jumper member 111 is bonded to two wirings 106, 107, and 108, among the plurality of wirings 101 to 110 of the wiring structure 100, in a state where it is bridged between the two wirings 106, 107, and 108. According to this configuration, the two wirings 106, 107, and 108 are bonded to each other with the jumper member 111 bridged therebetween, a short line can be constructed without detouring a wiring route of the wiring structure 100.
In the electronic control unit according to the present embodiment, the connector module 80 includes connector units 84 and 85 protruding from a first surface 82 opposite to the second surface (plane surface) 83. The electronic control unit further includes: a cover 33 in a form of a cylinder having a bottom covering the board module 50 and the connector module 80 and mounted around an outer circumferential portion of the mounting base 31 in a state where the connector units 84 and 85 of the connector module 80 are exposed to the outside via an opening 33a; a first seal member 35 sealing a gap between the first surface 82 of the connector module 80 and a bottom surface of the cover 33; and a second seal member 36 sealing a gap between an outer circumferential surface of the mounting base 31 and an inner surface of an outer circumferential portion of the cover 33. The cover 33 is fixed by caulking the outer circumferential portion of the cover 33, in a state where the bottom surface of the cover 33 presses the first seal member 35 against the connector module 80, such that the outer circumferential portion of the cover 33 is pressed against the outer circumferential surface of the mounting base 31. According to this configuration, the cover 33 can be fixed to the mounting base 31 in a state where the functions of the first seal member 35 and the second seal member 36 are exhibited without using a fastening member. As such a fastening member for fixing the cover 33 is not necessary, the board module 50 and the connector module 80 can secure a space for mounting electronic components, thereby efficiently arranging the electronic components.
[Other Embodiments] In the embodiment described above, an example in which the electronic control unit of the present invention is applied to an electric power steering device has been described. However, the present invention can be applied to any electronic control unit as long as the electronic control unit includes a board module on which an electric circuit is formed, a board module in which an electric circuit is formed on a board, and a connector module holding a wiring structure.
In addition, the present invention is not limited to the above-described embodiment, and includes various modifications. The above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to having all the configurations described above. Some of the configurations of one embodiment may be replaced with configurations of another embodiment, and configurations of one embodiment may be added to configurations of another embodiment. In addition, other configurations may be added to some of the configurations of each embodiment, some of the configurations of each embodiment may be deleted, or some of the configurations of each embodiment may be replaced with other configurations.
For example, in the above-described embodiment, the electronic control unit 30 including a two-system electric circuit has been described as an example. However, the present invention is also applicable to an electronic control unit including a one-system electric circuit.
In addition, in the above-described embodiment, it has been described as an example that only portions bonded to the electronic components 92, 93, 96, 97, and 98 in the embedded parts of the wiring structure 100 embedded in the connector base (base) 81 of the connector module 80 are exposed toward the second surface (plane surface) 83 of the connector base (base) 81. However, the embedded parts of the wiring structure 100 may be configured to entirely expose surfaces thereof facing the second surface (plane surface) 83 of the connector base (base) 81. Even in this case, only spaces for placing the electronic components 92, 93, 96, 97, and 98 are required at the time of bonding the electronic components 92, 93, 96, 97, and 98, and it is not necessary to secure extra spaces for securing bonding portions between the electronic components 92, 93, 96, 97, and 98 and the wiring structure 100. Therefore, downsizing can be achieved.
In the embodiment described above, an example in which the electronic control unit of the present invention is applied to an electric power steering device has been described. However, the present invention can be applied to any electronic control unit as long as the electronic control unit includes a board module on which an electric circuit is formed, a board module in which an electric circuit is formed on a board, and a connector module holding a wiring structure.
In addition, the present invention is not limited to the above-described embodiment, and includes various modifications. The above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to having all the configurations described above. Some of the configurations of one embodiment may be replaced with configurations of another embodiment, and configurations of one embodiment may be added to configurations of another embodiment. In addition, other configurations may be added to some of the configurations of each embodiment, some of the configurations of each embodiment may be deleted, or some of the configurations of each embodiment may be replaced with other configurations.
For example, in the above-described embodiment, the electronic control unit 30 including a two-system electric circuit has been described as an example. However, the present invention is also applicable to an electronic control unit including a one-system electric circuit.
In addition, in the above-described embodiment, it has been described as an example that only portions bonded to the electronic components 92, 93, 96, 97, and 98 in the embedded parts of the wiring structure 100 embedded in the connector base (base) 81 of the connector module 80 are exposed toward the second surface (plane surface) 83 of the connector base (base) 81. However, the embedded parts of the wiring structure 100 may be configured to entirely expose surfaces thereof facing the second surface (plane surface) 83 of the connector base (base) 81. Even in this case, only spaces for placing the electronic components 92, 93, 96, 97, and 98 are required at the time of bonding the electronic components 92, 93, 96, 97, and 98, and it is not necessary to secure extra spaces for securing bonding portions between the electronic components 92, 93, 96, 97, and 98 and the wiring structure 100. Therefore, downsizing can be achieved.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2019-173478 | Sep 2019 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2020/030858 | 8/14/2020 | WO |
