Integrated pump device

Abstract

In the integrated pump device (10), a motor portion (20), a pump portion (30), and a substrate (26) are integrated. In the pump portion (30), a pump rotating body (pump gear) (32) housed in a pump housing (31) rotates by a driving force of the motor portion (20) to generate hydraulic pressure for operating a hydraulic actuator portion (60). The substrate (26) is provided on a substrate seating surface (36) recessed on a side of the pump housing (31) opposite the motor portion (30), and a plurality of electronic elements (266, 267, 268) that constitute a control circuit for controlling driving of the motor portion (20) are mounted. A heat dissipation material (29) is applied or sandwiched between the substrate (26) and the substrate seating surface (36) at a position where at least an electronic element that generates heat due to energization among the plurality of electronic elements is mounted.

Description

Cross-reference of related applications

[0001] This application is based on Japanese Application No. 2024-043144, filed on March 19, 2024, the contents of which are incorporated herein by reference. Technical Field

[0002] This invention relates to integrated pump devices. Background Technology

[0003] Previously, devices that integrate a motor and an actuator were known. For example, the device disclosed in Patent Document 1 includes an electric motor, a circuit board with a control unit for controlling the electric motor, and an output shaft of a transmission. The circuit board is disposed between the electric motor and the output shaft of the transmission.

[0004] Patent document 2 discloses an integrated pump device that combines a motor, an oil pump, and a hydraulic parking lock actuator. The oil pump supplies oil for cooling or lubrication to oil-consuming devices such as MG (electric generator) via the hydraulic parking lock actuator.

[0005] Existing technical documents Patent documents Patent Document 1: Japanese Patent Publication No. 2023-531627 Patent Document 2: Japanese Patent Application Publication No. 2023-093012 Summary of the Invention

[0006] Patent Document 2 describes an integrated pump device that converts electrical power into hydraulic flow by driving an oil pump connected to the motor's output shaft. When the pump starts, the power consumption required to start the motor increases due to factors such as pump resistance. Furthermore, for example, with an oil pump that supplies cooling oil to the MG, the motor's power consumption also increases when the MG load is high and the required oil flow increases depending on the vehicle's driving conditions.

[0007] When the motor consumes a lot of power, the electronic components in the circuit board that houses the control circuitry that drives the motor generate heat, and the temperature of the electronic components and the circuit board may exceed their heat resistance temperature. If a dedicated heat sink is used for heat dissipation, the device becomes larger and the number of components increases. Patent Document 1 does not mention any solutions to the problem related to heat dissipation of electronic components on the circuit board.

[0008] The purpose of this disclosure is to provide an integrated pump device that uses the output of a motor to drive an oil pump, which appropriately dissipates the heat generated by electronic components mounted on a substrate.

[0009] In the integrated pump device disclosed herein, the motor unit, the pump unit, and the base plate are integrated into one unit. The pump rotating body of the pump unit, housed in the pump housing, rotates under the driving force of the motor unit, generating hydraulic pressure to operate the hydraulic actuator unit.

[0010] A substrate is provided on a substrate seat surface recessed on the side of the pump housing opposite to the motor section, and multiple electronic components constituting a control circuit for controlling the drive of the motor section are mounted thereon.

[0011] In the area where at least one of the multiple electronic components that generates heat when powered on is mounted, a heat-dissipating material is applied or clamped between the substrate and the substrate base.

[0012] The heat generated by the electronic components mounted on the substrate is dissipated to the pump housing via a heat-dissipating material coated or sandwiched directly beneath the substrate. The heat received by the pump housing is then dissipated into the oil flowing inside the pump housing. Thus, the heat generated by the electronic components mounted on the substrate can be adequately dissipated without the need for a dedicated heat sink. Attached Figure Description

[0013] The above-mentioned and other objects, features, and advantages of this disclosure will become more apparent from the accompanying drawings and from the detailed description below.

[0014] Figure 1 This is an axial schematic cross-sectional view of an integrated pump device according to one embodiment.

[0015] Figure 2 yes Figure 1 The diagram is taken from the hydraulic actuator section at line II-II.

[0016] Figure 3 yes Figure 1 The diagram is taken from the motor side at line III-III.

[0017] Figure 4 This is a structural diagram of the integrated pump unit and parking locking mechanism.

[0018] Figure 5 It is a graph illustrating the changes in fuel required in relation to the vehicle's driving conditions.

[0019] Figure 6 It is a diagram showing the configuration of electronic components that are used as the evaluation object for cooling effect.

[0020] Figure 7 This is a diagram illustrating the cooling effect on electronic components achieved by applying thermal gel.

[0021] Figure 8 This is a diagram showing the location of the resonance point detection.

[0022] Figure 9This is a graph showing the application range of the heat dissipation gel in resonance evaluation.

[0023] Figure 10 This diagram illustrates the resonance suppression effect achieved by applying a heat-dissipating gel. Detailed Implementation

[0024] (One implementation method) Based on the accompanying drawings, an integrated pump device according to one embodiment will be described. In the integrated pump device, at least the motor section, the pump section that operates the hydraulic actuator section, and the base plate are integrated into one unit. The integrated pump device of this embodiment is mainly installed in electric vehicles such as electric vehicles and hybrid electric vehicles, and is a device that combines the functions of PLA (parking lock actuator) and EOP (electric oil pump). The PLA function is the function of switching the locked state and the unlocked state of the parking lock mechanism. The EOP function is the function of supplying cooling or lubricating oil to fuel-consuming devices such as MG (electric generator).

[0025] More specifically, the integrated pump device of this embodiment is, for example, mounted on an autonomous electric vehicle. When a start or park command is received from the vehicle's host control device, the parking lock mechanism is activated. Furthermore, based on the engine speed, load status, and other parameters of the MG (motor engine) while the vehicle is in motion and the parking lock mechanism is unlocked, the amount of oil supplied to the MG is adjusted.

[0026] First, refer to Figures 1-3 The overall structure of the integrated pump device 10 according to one embodiment will be described. For example... Figure 1 As shown, in one embodiment, the integrated pump device 10, in addition to the motor unit 20, the pump unit 30 and the base plate 26, also integrally comprises a hydraulic actuator unit 60 that operates by hydraulic pressure supplied from the pump unit 30.

[0027] The motor section 20 and the pump section 30 are coaxially arranged relative to a common motor shaft O. In one embodiment, a rotary hydraulic actuator section 60 is used. The actuator shaft Q of the hydraulic actuator section 60 is arranged coaxially or parallel to the motor shaft O. As described in "Other Embodiments", a cylinder-type hydraulic actuator section may also be used.

[0028] The motor unit 20 includes a stator 22 housed in a motor housing 21 and a motor rotor 23. A rotating magnetic field is generated by energizing the three-phase windings wound around the stator 22. The motor rotor 23 has multiple magnetic poles arranged circumferentially and rotates bidirectionally according to the rotating magnetic field of the stator 22. A motor output shaft 24 is passed through and fixed at the center of the motor rotor 23.

[0029] The end of the motor output shaft 24 on the motor housing 21 side is supported by a bearing 215, and the end on the opposite side of the motor section 20 is connected to the internal gear 321 of the pump gear 32. In the middle part of the motor output shaft 24, an oil seal 246 is provided along the outer circumferential surface to seal the oil leaking from the pump chamber 33 to the motor section 20 side.

[0030] The pump gear 32 of the pump section 30, which serves as a "pump rotating body" housed in the pump housing 31, rotates under the driving force of the motor section 20, generating hydraulic pressure that operates the hydraulic actuator section 60. In one embodiment, the pump housing 31 is made of aluminum alloy.

[0031] like Figure 2 As shown, a pump chamber 33 is formed on the side of the pump housing 31 opposite to the hydraulic actuator section 60. By rotating the motor output shaft 24, the internal gear 321 rotates inside the external gear 322, thereby pumping oil from the pump chamber 33. Figure 2 In the direction of observation, clockwise rotation of the pump gear 32 is defined as "forward rotation," and counterclockwise rotation is defined as "reverse rotation." The working direction of the hydraulic actuator section 60 is switched according to the rotation direction of the pump gear 32.

[0032] A first oil passage 331 and a second oil passage 332, communicating with the pump chamber 33, are formed on the left and right sides of the figure, separated by an internal gear 321. The first oil passage 331 is the discharge oil passage during reverse rotation and communicates with the forward hydraulic chamber of the hydraulic actuator section 60. The second oil passage 332 is the discharge oil passage during forward rotation and communicates with the return hydraulic chamber of the hydraulic actuator section 60. A slide valve 40 for switching the suction oil passage is provided upstream of the pump chamber 33. The slide valve 40 is housed in a valve hole 34 formed in the pump housing 31.

[0033] On the side of the pump housing 31 opposite the motor section 20, a cylindrical protrusion 37 supporting the motor output shaft 24 is provided in the center. Additionally, a substrate 26 is provided on a substrate seat surface 36 recessed around the protrusion 37. The surface of the substrate 26 facing the motor section 20 is referred to as the "motor surface 261," and the surface facing the substrate seat surface 36 is referred to as the "pump surface 262." Multiple electronic components 266, 267, and 268 constituting a control circuit for controlling the drive of the motor section 20 are mainly mounted on the motor surface 261 of the substrate 26. Power and signals are input to the control circuit from the outside via a connector 39 provided on the pump housing 31.

[0034] like Figure 3As shown, the various electronic components include capacitor 266, inductor 267, and MOSFET (hereinafter referred to as "MOS") 268. For example, capacitor 266 and inductor 267 form an LC circuit as noise suppression components for the power input section. The three-phase inverter circuit composed of multiple MOS 268 converts the DC power supplied from the vehicle battery to connector 39 into three-phase AC power and supplies it to the three-phase windings of the brushless motor.

[0035] like Figure 1 As shown, at the locations where electronic components 266, 267, and 268 are mounted, a heat-dissipating material 29 is applied or sandwiched between the pump surface 262 of the substrate 26 and the substrate base surface 36. In one embodiment, the heat-dissipating gel 29, which is a gel-like heat-dissipating material, is applied directly below each electronic component 266, 267, and 268 between the substrate 26 and the substrate base surface 36. The technical significance of this structure will be described later. Here, "directly below" means "a position relative to the electronic component across the substrate 26," not "below in the vertical direction."

[0036] A pump plate 50 forming an oil passage is provided between the pump section 30 and the hydraulic actuator section 60. The pump plate 50 and the pump housing 31 together form the frame of the pump section 30. An inlet 67 and an outlet 68 are formed in the blade housing 61 of the hydraulic actuator section 60. The inlet 67 communicates with the valve hole 34 of the pump housing 31. The outlet 68 communicates with a blade chamber 62 of the blade housing 61.

[0037] Oil drawn into the suction port 67 is pumped through the communication space of the slide valve 40 by the rotation of the pump gear 32. The pumped oil is directed into the vane chamber 62 of the hydraulic actuator section 60 in the direction of rotation of the pump section 30. Corresponding to the working position of the vane rotor 63, the oil is discharged from the discharge port 68 and supplied as cooling oil or lubricating oil to oil consuming devices such as the MG97 (see reference). Figure 4 The rotational output of the blade rotor 63 is transmitted to the stop mechanism of the parking locking mechanism 80 (see reference). Figure 4 The hydraulic actuator section 60 rotates the vane rotor 63 by the hydraulic pressure generated by the pump section 30, thereby activating the parking locking mechanism 80.

[0038] Next, refer to Figure 4 The operation of the parking locking mechanism 80 caused by the integrated pump device 10 will be explained. Figure 4 This illustrates an example of a system structure. The parking locking mechanism 80 includes a stopping mechanism comprising a stop shaft 81, a stop plate 82, a stop spring 83, a stop roller 84, a parking lever 85, a cone 86, a parking locking lever 87, a parking gear 88, etc.

[0039] The stop mechanism switches between the P position and the non-P position via the output of the hydraulic actuator section 60. The stop shaft 81 is connected to the rotation shaft of the vane rotor 63 of the hydraulic actuator section 60, and rotates in two directions within a specified angle range through the operation of the vane rotor 63. The stop plate 82 is fixed to the stop shaft 81 and rotates together with the stop shaft 81. For example, in a two-position stop mechanism, the stop plate 82 has two valleys 821 and 822 and a peak 825 on its radial outer edge. In other structural examples, a stop mechanism with three or more positions can also be used.

[0040] The stop roller 84, supported at the top of the stop spring 83, is engaged in one of the two valleys 821, 822 by the elastic force of the stop spring 83. When a rotational force exceeding a predetermined value is applied to the stop plate 82, the stop spring 83 elastically deforms, and the stop roller 84 moves from one valley across the peak 825 to the other valley. This switches between the P position and the non-P position.

[0041] The parking lever 85 is roughly L-shaped, with one end 851 fixed to the stop plate 82. At the other end 852 of the parking lever 85, a cone 86 is provided that decreases in diameter as it approaches the other end 852. When the stop plate 82 rotates in the direction that causes the stop roller 84 to engage with the valley 821, the cone 86 moves in the direction of arrow P. When the stop plate 82 rotates in the direction that causes the stop roller 84 to engage with the valley 822, the cone 86 moves in the direction other than arrow P.

[0042] The parking lock lever 87 abuts against the conical surface of the cone 86 and can swing about the shaft 877. The parking lock lever 87 has a protrusion 878 that engages with the parking gear 88. When the cone 86 moves in the direction of arrow P, the parking lock lever 87 is pushed upwards, and the protrusion 878 engages with the parking gear 88, locking the lever. When the cone 86 moves in a direction other than arrow P, the protrusion 878 disengages from the parking gear 88, releasing the lock.

[0043] In this way, the integrated pump unit 10 utilizes the driving force of the motor unit 20 to operate the hydraulic actuator unit 60 through the hydraulic pressure supplied by the pump unit 30, thereby realizing the PLA function. In addition, the integrated pump unit 10 supplies oil for cooling or lubrication to oil-consuming devices such as the MG97 through the EOP function, which discharges oil drawn in from the suction port 67 from the discharge port 68 by rotating the pump unit 30.

[0044] Furthermore, when pump unit 30 starts, the power consumption required for motor startup increases due to factors such as oil pumping resistance. Additionally, depending on the vehicle's driving conditions, motor power consumption also increases when the MG load is high and the required oil flow rate increases. Specifically, refer to... Figure 5The required oil volume and motor speed corresponding to the vehicle's driving state are explained. A positive value for the required motor speed means that the motor rotor 23 rotates in the forward direction, and a negative value means that the motor rotor 23 rotates in the reverse direction. The motor rotor 23 rotates in the forward direction when the vehicle is in motion or when the parking lock is released, and rotates in the reverse direction when the vehicle is stopped or when the parking lock is engaged.

[0045] When driving on flat ground, the MG load is stable. If driving uphill, the MG load increases, and the required fuel quantity and the required motor speed increase from the values ​​observed on flat ground. If the vehicle stops after driving uphill, the required motor speed changes from positive to negative, and from forward to reverse rotation. MG cooling continues as the absolute values ​​of the required fuel quantity and the required motor speed gradually decrease towards 0 from the time the vehicle stops. MG cooling ceases when the required fuel quantity and the required motor speed reach 0.

[0046] The vehicle resumes driving and transitions to downhill driving. The MG load is lower downhill than on flat ground, and the required fuel and motor speed are fixed at positive values, lower than on flat ground. This state continues until the vehicle resumes low-load driving after the downhill section. When the vehicle stops after low-load driving, the absolute values ​​of the required fuel and negative motor speed temporarily increase to their maximum levels before becoming zero.

[0047] From the vehicle's upper-level control device, the control circuit of the integrated pump unit 10 receives commands for executing and releasing the parking lock, as well as the required motor speed corresponding to the vehicle's driving state, as a rotation indicator value. In the integrated pump unit 10, the higher the speed of the motor 20, the greater the amount of oil discharged from the pump 30 to the MG97.

[0048] Thus, when the motor consumes a lot of power, the electronic components 266, 267, and 268 in the substrate 26 generate heat, and the temperature of the electronic components 266, 267, and 268, as well as the substrate 26, may exceed their heat resistance temperature. If a dedicated heat sink is provided for the substrate 26, which is located in the space between the motor section 20 and the pump gear 32, there is a problem of increased device size and increased number of components. Therefore, in one embodiment, as... Figure 1 As shown, at the locations where electronic components 266, 267, and 268 are mounted, a heat dissipation gel 29, serving as a "heat dissipation material," is applied between the substrate 26 and the substrate base surface 36.

[0049] The heat generated by the electronic components 266, 267, and 268 mounted on the substrate 26 is dissipated to the pump housing 31 via the thermal gel 29 applied directly beneath the substrate 26. The heat received by the pump housing 31 is dissipated into the oil flowing inside the pump housing 31 for cooling the MG97, etc. Therefore, the heat generated by the electronic components 266, 267, and 268 mounted on the substrate 26 can be adequately dissipated without a dedicated heat sink. In one embodiment, the pump housing 31 is formed of an aluminum alloy, which is a metal with high thermal conductivity, thus further improving cooling performance.

[0050] In another embodiment, a heat-dissipating gel 29, i.e., a gel-like material, is used as a "heat-dissipating material". By using a gel-like material with a low Young's modulus, the stress on the substrate 26 is alleviated for stresses caused by the thermal expansion differences of the constituent components and various vibration stresses caused by vehicle mounting.

[0051] Next, refer to Figures 6-10 Regarding the cooling effect and resonance suppression effect, the method and results of the evaluation test comparing the characteristics of the example with heat dissipation gel 29 and the comparative example without coating are explained.

[0052] Figure 6 This indicates the arrangement of electronic components 266, 267, and 268 on the motor surface 261 of substrate 26. Symbols C8 to C11 represent capacitor 266, symbol L represents inductor 267, and symbols M1 to M7 represent MOSFET 268. In this embodiment, thermal gel 29 is applied to the portion enclosed by the dashed box. After the control circuit is energized for a specified time under specified driving conditions, the temperatures of capacitor 266 (C8), inductor 267 (L), and MOSFET 268 (M3), marked with *, are measured.

[0053] Figure 7 This represents the results obtained by comparing the temperatures of each electronic component 266, 267, and 268 in the embodiments and comparative examples after power-on. Regarding the temperature on the vertical axis, no absolute values ​​are shown; only relative temperature differences are indicated. In the embodiment where thermal gel 29 was applied, a temperature reduction effect was observed for the capacitor (8°C), inductor (8°C), and MOS (16°C) compared to the uncoated comparative example.

[0054] Figure 8 This indicates the detection location of the resonance point in the resonance evaluation. The resonance point is detected in the protrusion 37 (R part) of the motor surface 261 of the substrate 26, where multiple capacitors 266 and inductors 267 are arranged around it. Figure 9 This indicates the application area of ​​the heat dissipation gel 29 in the resonance evaluation. It is shown in the annular portion surrounding the protrusion 37 and in its arrangement with the electronic components 266, 267, and 268 (see reference). Figure 8The corresponding part has thermal gel 29 applied to the substrate base surface 36.

[0055] Figure 10 The frequency characteristics represent the resonance ratio in the 400–2000 Hz frequency band. In the comparative example without thermal gel coating, peak values ​​of approximately 6–10 times the resonance ratio were observed near 800 Hz, 1100 Hz, and 1500 Hz. On the other hand, in the embodiment with thermal gel 29 coating, the resonance ratio was suppressed to less than 1–2 times in the 400–2000 Hz frequency band.

[0056] (Other implementation methods) (a)6、 Figure 9 In the example shown, thermal gel 29 is applied to all capacitors 266, inductors 267, and MOSFETs 268 on substrate 26. However, depending on the structure of the control circuit, if the multiple electronic components mounted on substrate 26 include "electronic components that do not generate heat when powered on," then these "electronic components that do not generate heat when powered on" can be excluded from the application of thermal gel 29. That is, thermal gel 29 can be applied between substrate 26 and substrate base 36 only to the "location where at least one of the multiple electronic components that generates heat when powered on is mounted."

[0057] (b) The structure is not limited to applying a gel-like heat-dissipating material 29 between the substrate 26 and the substrate base surface 36, but also includes sandwiching a sheet-like (film-like) heat-dissipating material 29 between the substrate 26 and the substrate base surface 36.

[0058] (c) The pump housing 31 is not limited to aluminum alloy, but may also be formed of other metal materials with high thermal conductivity. Alternatively, the pump housing 31 may also be formed of resin material. Even if formed of resin material, the pump housing 31 has a cooling effect by the internal flow of cooling oil.

[0059] (d) As a “pump rotating body”, a rotating body other than a gear can also be used.

[0060] (e) In contrast to an integrated pump device in which the motor unit 20, pump unit 30, and base plate 26 are integrally formed, the hydraulic actuator unit 60 can also be provided separately. Furthermore, the hydraulic actuator unit 60 is not limited to a rotary hydraulic actuator, but can also use a cylinder-type hydraulic actuator.

[0061] (f) The application of the integrated pump device 10 disclosed herein is not limited to activating the parking lock mechanism 80 of an electric vehicle. Any integrated pump device that generates hydraulic pressure to activate the hydraulic actuator 60 by rotating the pump unit 30 through the driving force of the motor unit 20 is acceptable.

[0062] The present disclosure is not limited to the above-described embodiments and can be implemented in various ways without departing from its spirit.

[0063] This disclosure is described based on embodiments. However, this disclosure is not limited to these embodiments and structures. This disclosure also includes various modifications and modifications within the same scope. In addition, various combinations and forms, as well as other combinations and forms including only one element, more than one element, or less than one element, also fall within the scope and spirit of this disclosure.

Claims

1. An integrated pump device, The integral structure consists of: Motor section (20); The pump section (30), with its rotating body (32) housed in the pump housing (31), rotates under the driving force of the motor section, generating hydraulic pressure to operate the hydraulic actuator section (60); and A substrate (26) is provided on a substrate seat surface (36) recessed on the side of the pump housing opposite to the motor unit, and multiple electronic components (266, 267, 268) constituting a control circuit for controlling the drive of the motor unit are mounted thereon. At the location where at least one of the multiple electronic components that generates heat when energized is mounted, a heat-dissipating material is applied or clamped between the substrate and the substrate base surface (29).

2. The integrated pump device as described in claim 1, The pump housing is made of aluminum alloy.

3. The integrated pump device as described in claim 1 or 2, The heat-dissipating material is a gel-like material.

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