JP7131104B2 - motor controller - Google Patents

Description

The present invention relates to a motor control device.

For example, an electric valve timing adjustment device (E-VCT (Variable Cam Timing)) is composed of a phase adjustment mechanism and a motor control device. A motor control device includes a motor and a drive device (hereinafter referred to as an EDU (Electronic Driver Unit)). The motor and EDU are electrically connected by a connector mounted on the EDU board.

Since the connector is cantilever-supported by the EDU board and protrudes from the EDU board, it is violently shaken by vibrations during engine rotation and running. Therefore, in order to secure the vibration resistance of the connector, the connector is fixed to the housing by, for example, a thermosetting adhesive (see Patent Document 1). The thermosetting adhesive is liquid when applied, but becomes a solid when heat-cured during assembly, and the connector is adhered and fixed to the housing.

JP 2018-7417 A

By the way, since the adhesive before heat curing is liquid and has fluidity, a holding portion surrounded by a wall portion is recessed in a portion facing the connector in the housing, and the adhesive is applied to the holding portion. I'm trying to apply it. Since the adhesive applied to the holding portion is held so as not to flow out, the adhesive applied to the holding portion adheres to the connector when the EDU substrate is assembled into the housing. When the adhesive is heated and cured in this state, the connector can be adhered and fixed to the housing.

Here, the bonding area between the connector and the housing is important for the vibration-proof design of the connector. The reality is that even the amount of adhesive cannot be increased due to equipment requirements during assembly.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a motor control device capable of improving vibration resistance of a connector for connecting a drive board and windings of a motor.

According to the first aspect of the invention, when the connector (34) is pressed against the adhesive (42) supplied to the holding part (41) during assembly of the product, the adhesive is pushed to one side of the through hole (43) by capillary action. is sucked up from one opening (43a) and overflows from the other opening (43b). As a result, when the adhesive is hardened, the connector is latched to the housing by the adhesive, so that the bonding area can be increased and the bonding strength can be increased.

FIG. 2 is a longitudinal side view of the internal connector in the first embodiment; FIG. 1 is a longitudinal sectional view schematically showing a motor control device; Perspective view of motor controller and motor Top view of motor controller Top view of internal connector A diagram showing the relationship between the inner diameter of the pipe and the height of the liquid level rise Vertical side view of through hole Plan view of internal connector showing formation positions of through holes Vertical side view of through hole Longitudinal side view of a through-hole showing a modified example (part 1) Longitudinal side view of a through-hole showing a modified example (part 2)

An embodiment applied to a valve timing adjusting device will be described with reference to the drawings.
A valve timing adjusting device 1 shown in FIG. 2 is provided in a rotation transmission system for transmitting rotation of a crank from a crankshaft (not shown) of an internal combustion engine to a camshaft 2 in a vehicle. The camshaft 2 opens and closes intake valves (not shown) according to the rotation of the crank. The valve timing adjusting device 1 has a function of controlling the camshaft 2 to advance or retard the rotation of the crank.

A valve timing adjusting device 1 is composed of a phase adjusting mechanism 3 and a motor control device 4 . The phase adjustment mechanism 3 is rotated by a chain (not shown) connected to a crank, and transmits its rotation to the camshaft 2 in a state of being advanced or retarded by the motor control device 4 . The valve timing adjusting device 1 is basically the same as the configuration disclosed in Japanese Patent Application Laid-Open No. 2015-203392 filed by the present applicant. detailed description is omitted.

The motor control device 4 will be explained.
The motor control device 4 is an integrated electromechanical product including a motor 5 and a drive device (EDU: Electronic Driver Unit) 6, and is attached to a stationary portion such as a chain case of an internal combustion engine.

The motor 5 is a brushless permanent magnet type synchronous motor, and as shown in FIG. there is

The motor housing 7 is made of iron, for example, and is shaped like a flat container with a flange. The base 8 is made of aluminum, for example, and is fixed so as to close the opening of the motor housing 7 . The motor housing 7 and the base 8 form a housing for the motor 5, and the motor 5 is formed by assembling various components inside.

The tip of the motor shaft 11 protrudes outside from the motor housing 7 and is connected to the phase adjustment mechanism 3 . Specifically, a hole 15 is formed at the tip of the motor shaft 11 , and a joint 17 is attached to the tip of the motor shaft 11 by inserting a pin 16 into the hole 15 . This joint 17 is for flexibly connecting the motor control device 4 to the phase adjustment mechanism 3 . An opening 18 is formed in the motor housing 7, and a ring-shaped seal 19 is attached to the opening 18 so that the inside of the motor 5 is waterproof.

The rotor 12 is provided integrally with the motor shaft 11, and includes a permanent magnet 20 that is the main component of the rotor magnetic flux, two fixed plates 21 and 22 that rectify the magnetic flux generated by the permanent magnet 20, and the permanent magnet 20 on its circumferential surface. It consists of one or a plurality of permanent magnets 23 provided on the . The permanent magnet 23 exhibits the function of assisting and rectifying the rotor magnetic flux.
The sensor magnet 13 is fixed to the surface of the rotor 12 facing the base 8, and is provided so that the polarity facing the base 8 is switched at every predetermined angle.

The stator 14 is housed in the motor housing 7 in a positioned state, and includes an annular stator core 24 having a plurality of teeth portions 24a projecting inwardly, and a stator winding wound around the teeth portions 24a via a resin bobbin 25. It consists of lines 26 . The stator windings 26 are provided corresponding to the U, V, and W phases of the motor 5, and are electrically connected to each other through terminals 27 for forming a neutral point. The stator 14 generates a rotating magnetic field when a drive current is supplied to the stator windings 26 .

The drive device 6 includes a cover 28 and an EDU board 29 (corresponding to a drive board) in addition to the base 8 described above. The cover 28 is made of iron, for example, and the base 8 and the cover 28 form a housing of the driving device 6 .

The EDU board 29 is fixed to the base 8 with screws 30, as shown in FIG. A plurality of components that constitute an inverter circuit for driving the motor 5 are mounted on the EDU board 29 . Components include MOSFETs, drive ICs, coils, and capacitors.

A Hall element 31 is mounted on the back surface of the EDU substrate 29 as shown in FIG. A window portion 32 is formed in the base 8 , and the Hall element 31 is positioned in the window portion 32 and faces the sensor magnet 13 . The Hall element 31 detects the rotational position of the sensor magnet 13 and outputs a detection signal to the driving IC.

The drive IC detects the rotational position of the rotor 12 based on the detection signal of each Hall element 31 . Further, the drive IC acquires a signal indicating the rotation direction and rotation speed of the motor 5 from an ECU (not shown), and based on this instruction signal and the rotation position, generates and outputs a gate drive signal for each MOSFET. do.

As shown in FIG. 4, the EDU board 29 is mounted with an external connector 33 for connection with an ECU (not shown) and an internal connector 34 for connection with the motor 5 .
The external connector 33 faces the outside from the base 8 and outputs to the EDU board 29 an instruction signal for the motor 5 output from an ECU (not shown). Further, it outputs a diagnostic signal output from the EDU board 29 and a signal indicating the actual number of rotations and the actual rotation direction of the motor 5 to the ECU. Power is supplied to the EDU board 29 via an external connector 33 .

The internal connector 34 is formed by insert-molding three terminals 35 corresponding to the three phases of the inverter circuit into the connector housing 36 . As shown in FIG. 5, the base end portion 35a of the terminal 35 protrudes from the upper side surface in the drawing, and the tip end portion 35b protrudes from the lower side surface in the drawing. The internal connector 34 is cantilevered on the EDU board 29 by fixing the base ends 35 a of the terminals 35 to the EDU board 29 . A window portion 37 is formed in the base 8 , and the tip portion 35 b side of the terminal 35 faces the motor 5 side through the window portion 37 . Each end portion 26a of the stator winding 26 of the motor 5 is thermally caulked to the tip portion 35b of the terminal 35 while passing through the window portion 37. As shown in FIG. Thereby, the three-phase output lines of the inverter circuit and the stator windings 26 of the motor 5 are electrically connected.

Here, a plurality of thinning holes 38 are formed in the upper surface of the internal connector 34 . In this embodiment, the strength of the internal connector 34 is ensured by forming the thinning hole 38 at the portion where the terminal 35 is positioned. A plurality of holes 39 are formed in the lower surface (corresponding to the contact surface) of the internal connector 34 . This hole portion 39 corresponds to a boss for supporting the terminal 35 in the mold during insert molding. In the present embodiment, the hole 39 is formed in the lower surface below the meat stealing hole 38 , but the hole 39 may be formed in a portion that does not correspond to the meat stealing hole 38 .

Now, as described above, the internal connector 34 is cantilevered on the EDU board 29, and is greatly shaken by the rotation of the engine and vibration during running. It is adhered and fixed by a type of silicone adhesive (hereinafter referred to as adhesive) 42 .

Since the adhesive 42 before heat curing is liquid and has fluidity, the holding portion 41 surrounded by the wall portion 40 is recessed in the base 8 so that the adhesive 42 applied to the base 8 does not flow out. Then, the holding portion 41 is held by applying an adhesive 42 thereto. In this case, if the internal connector 34 is in contact with the base 8 , there is a risk that excessive force will be applied to the fixing location of the internal connector 34 on the EDU board 29 . It is designed so that a slight gap exists between the connector 34 and the holding portion 41 .

By the way, although the internal connector 34 is violently shaken by vibrations caused by rotation of the engine and running of the vehicle, the adhesion area to the conventional internal connector 34 is small. there is

For this reason, in this embodiment, as shown in FIG. made it That is, one opening 43 a of the through hole 43 is provided on the bottom surface of the internal connector 34 , and the other opening 43 b is provided on the bottom surface of the thinning hole 38 . A counterbore 44 is formed on the peripheral edge of the other opening 43 b of the through hole 43 .

When the adhesive 42 is applied to the holding portion 41 by a dispenser during product assembly and the EDU board 29 is screwed to the base 8 , the internal connector 34 is pressed against the adhesive 42 . Then, the adhesive 42 is sucked into the through hole 43 by capillary action and overflows into the counterbore portion 44 . As shown in FIG. 1, the adhesive 42 overflowing from the through-hole 43 takes the shape of a rivet due to its surface tension, so that when it is thermally cured by a heater, the internal connector 34 becomes as if it were rivet-locked to the base. .

In this embodiment, since the through holes 43 are formed so as to communicate with the thinning holes 38 formed in the internal connector 34, the representative value of the height dimension of the through holes 43 is 1.6 mm. In this case, if the viscosity of the adhesive is 50 mPa·s @ 25° C., the size of the inner diameter that the adhesive 42 can rise by capillary action is defined as follows.

That is, assuming that the representative value of the height dimension of the through-hole 43 is 1.6 mm, as shown in FIG. Therefore, when the representative value of the height dimension of the through-holes 43 is 1.6 mm, the inner diameter of the through-holes 43 must be set to φ2 or less as shown in FIG. Φ1 to Φ2 are desirable in consideration of .

As for the shape of the counterbored portion 44 in the upper portion of the through hole 43, it is desirable to form a chamfered portion 45 on the periphery of the opening 43b of the through hole 43 as shown in FIG. In other words, if the hole expands rapidly, the adhesive 42 sucked up by capillary action stays due to surface tension and the liquid level rise becomes insufficient, so it is possible that the rivet shape cannot be formed. Therefore, it can be expected that the rivet shape can be easily formed by providing the chamfered portion 45 so as to gradually increase the inner diameter of the opening 43b of the through hole 43 .

Now, since the internal connector 34 is cantilevered to the EDU board 29 by a mechanical connection (solder connection), the farther away the tip is from that portion, the more likely it is to be affected by vibration. Therefore, it is desirable to arrange the holes so that they are suitable for suppressing vibration, and to arrange them evenly and abundantly with respect to the width of the connector.

The influence of the position, number, layout and size of the through holes 43 in the internal connector 34 on the vibration resistance will be examined.
(1) The effect of the position of the through hole 43 is A<B<C<D<E<F shown in parentheses following the through hole 43 in FIG.
That is, since the vibration displacement increases as the EDU board 29 moves away from the mechanical joint of the internal connector 34, the bonding area at the portion where the vibration displacement is large can be increased to improve the vibration resistance.

(2) The greater the number, the greater the effect.
That is, as the number of through-holes 43 increases, the bonding area increases, so vibration resistance can be improved.

(3) Layout In the present embodiment, the through holes 43 are formed so as to communicate with the thinning holes 38. Therefore, assuming that the shape of the internal connector 34 is not changed, there is no layout pattern in which the through holes 43 can be formed. It is only shown in FIG. 8, and the examination is omitted.
(4) The locking effect due to the shape of the rivet is almost unaffected by the size of the inner diameter, since the shape of the rivet is almost the same.

According to such an embodiment, the following effects can be obtained.
The internal connector 34 is formed with a through-hole 43 that allows the adhesive 42 applied to the holding portion 41 to be sucked up by capillary action when the product is assembled. Thus, the internal connector 34 is latched to the base 8, and the synergistic effect of the improvement of the adhesion area and the latching effect makes it possible to improve the vibration resistance.

Since the through hole 43 communicating with the thinning hole 38 of the internal connector 34 is formed, the through hole 43 can cause the adhesive 42 to exhibit capillary action without significantly changing the shape of the internal connector 34. Holes 43 can be formed.

Since the internal connector 34 is cantilevered by the mechanical connecting portion, it is more susceptible to vibration as it moves away from that portion, and suppressing the vibration there increases the effect. Therefore, the vibration resistance can be improved by arranging the through hole 43 provided in the internal connector 34 far from the mechanical connection portion.

Since the internal connector 34 has an elongated shape, the anti-vibration effect can be enhanced by fixing both ends in addition to fixing one end surface with an adhesive. In addition, since the larger the number of through-holes 43, the greater the effect of latching, the vibration resistance can be improved by arranging many through-holes 43 evenly in the longitudinal direction of the connector.

Since the adhesive 42 is sucked up using capillary action, the smaller the hole diameter of the through-hole 43 provided in the internal connector 34 is, the larger the suction height of the adhesive 42 can be. Considering the thickness of the internal connector 34, moldability, and ease of sucking, Φ1 to Φ2 are appropriate.
By sucking up the adhesive 42 through the through-holes 43 , a secondary effect of suppressing the overflow of the adhesive 42 can be expected.

As shown in FIG. 9, one opening 43a of the through hole 43 located on the lower surface of the internal connector 34 may also be chamfered. In this case, it can be expected that the suction power of the adhesive 42 is improved by the surface tension of the opening of the through hole 43 .

(Other embodiments)
The shape of the through hole 43 may be a doglegged shape bent in the middle as shown in FIG. 10, or a Y shape branched in the middle as shown in FIG. In the case of the Y-shape, there are two hooking points, so that the hooking effect can be enhanced. In addition, in the case of a doglegged shape or a Y shape, even if the height dimension of the through hole 43 exceeds the height of the adhesive 42 that can be sucked up by capillary action, the latching shape can be formed. In this case, it is desirable to form the through hole 43 so that its horizontal cross-sectional area is constant. In other words, if the hole rapidly expands, the adhesive 42 sucked up by capillary action stays due to surface tension, making it difficult for the liquid level to rise. is constant, the latching shape can be stably formed.
The cross-sectional shape of the through-hole 43 is not limited to circular, and may be elliptical or polygonal.

Although the present disclosure has been described with reference to embodiments, it is understood that the present disclosure is not limited to such embodiments or structures. The present disclosure also includes various modifications and modifications within the equivalent range. In addition, various combinations and configurations, as well as other combinations and configurations, including single elements, more, or less, are within the scope and spirit of this disclosure.

In the drawings, 4 is a motor control device, 5 is a motor, 7 is a motor housing (housing), 8 is a base (housing), 29 is an EDU board (drive board), 34 is an internal connector (connector), and 35 is a terminal. , 35a is a base end portion, 35b is a tip portion, 36 is a connector housing, 38 is a thinning hole, 41 is a holding portion, 42 is an adhesive, 43 is a through hole, 44 is a counterbore portion, and 45 is a chamfer portion. .

Claims (8)

a motor (5);
housings (7, 8) of the motor;
a drive board (29) provided in the housing for driving the motor;
By fixing the base end (35a) of the terminal (35) to the driving substrate, the terminal (35) is adhered and fixed to the housing with an adhesive (42) in a cantilevered state on the driving substrate, a connector (34) for electrically connecting the drive board and the motor by connecting the windings of the motor to the tip (35b) of the terminal;
a holding portion (41) provided at a portion of the housing facing the connector and holding the supplied liquid adhesive so as not to flow out;
Penetration provided so as to penetrate the connector, one opening (43a) being located in the contact surface of the connector with the adhesive agent, and the other opening (43b) being located in a part other than the contact surface a hole (43);
The through-hole is formed in a shape that allows the adhesive to be sucked up from the one opening and overflow from the other opening due to capillary action during manufacture and assembly. 2. A motor control device according to claim 1, wherein said other opening is provided in a recess (38) formed in said connector housing (36). 3. The motor control device according to claim 1, wherein the through hole is provided with a countersunk portion (44) on the periphery of the other opening. 4. The motor control device according to any one of claims 1 to 3, wherein the through hole is provided with a chamfered portion (45) on the peripheral edge portion of the other opening. The motor control device according to any one of claims 1 to 4, wherein the through hole has a branched shape in which an intermediate portion is branched. 6. The motor control device according to any one of claims 1 to 5, wherein the through hole is provided close to the tip of the connector. The motor control device according to any one of claims 1 to 5, wherein the through holes are arranged at equal pitches in the longitudinal direction of the connector. The adhesive has a viscosity of 50 mPa s @ 25°C or less before heat curing,
The motor control device according to any one of claims 1 to 7, wherein the through hole has a length in the height direction of 1.6 mm or less and a diameter of Φ2 or less.

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