vehicle

Abstract

To provide a vehicle which enables reduction of noise during operation of a valve used for cooling an automatic transmission fluid.SOLUTION: A vehicle has: a coolant passage in which a coolant circulates; and a heat exchange device which conducts heat exchange between the coolant and an automatic transmission fluid. The coolant passage has an ATF passage which is connected to the heat exchange device and causes the coolant to circulate to the heat exchange device. The ATF passage is provided with a valve which may switch its state between a closing state in which the valve closes the ATF passage and an open state in which the valve opens the ATF passage. The vehicle has a control device which switches the valve into the closing state or the open state when predetermined conditions are satisfied. The control device switches the valve into the closing state or the open state when the predetermined conditions are satisfied and an approach notification system is operated.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle. [Background technology]

[0002] In recent years, in light of climate-related disasters, there has been growing interest in electric vehicles equipped with a motor as a drive source and hybrid electric vehicles equipped with an engine and a motor as a drive source in order to reduce CO2 emissions. Furthermore, automatic transmissions that convert torque from a drive source mounted on a vehicle and automatically change gears are widely adopted. With the aim of increasing the output of the drive source and improving the quality of automatic transmissions, automatic transmissions tend to shift gears more frequently, which increases the amount of heat generated by the automatic transmission. For this reason, a technology has been disclosed that suppresses the rise in oil temperature of automatic transmission fluid (hereinafter sometimes referred to as "ATF").

[0003] Patent Document 1 discloses an automatic transmission oil temperature control device that can appropriately suppress excessive oil temperature rise (overshoot) during high-load operation. The temperature control device includes a heat exchanger that exchanges heat between the automatic transmission oil and engine coolant, and a switching valve that switches whether the automatic transmission oil is circulated through the heat exchanger based on the temperature and load of the automatic transmission oil. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-48893 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the switching valve is operated in an environment with low background noise, such as when the vehicle is stopped or traveling at low speeds, the operating noise of the switching valve resonates inside the vehicle, which can degrade the marketability of the vehicle. In particular, when an electric vehicle or hybrid electric vehicle is traveling at low speeds while the motor is powered, there is no engine noise and road noise is low, making the operating noise of the switching valve more noticeable. This operating noise of the switching valve not only degrades the marketability of the vehicle, but may also erroneously lead vehicle users to believe that a malfunction has occurred.

[0006] The present invention has been made in view of the above-mentioned problems, and has an object to provide a vehicle that can reduce noise generated when a valve used to cool automatic transmission oil is operating. [Means for solving the problem]

[0007] (1) The present invention relates to a vehicle having a cooling water flow path through which cooling water flows and a heat exchanger that exchanges heat between the cooling water and automatic transmission oil, wherein the cooling water flow path has an ATF flow path that is connected to the heat exchanger and that flows the cooling water through the heat exchanger, the ATF flow path is provided with a valve that can be switched between a closed state that blocks the ATF flow path and an open state that opens the ATF flow path, and the vehicle has a control device that switches the valve to the closed state or the open state when a predetermined condition is met, and the control device switches the valve to the closed state or the open state when the predetermined condition is met and an approach notification system is activated.

[0008] According to the invention (1), a vehicle can be provided that can reduce noise generated when a valve used to cool automatic transmission oil is operating.

[0009] (2) The vehicle described in (1), wherein the valve is normally open, and the control device prohibits the valve from switching to the closed state from the time the vehicle is started until the approach notification system is activated, and switches the valve to the closed state when the approach notification system is activated.

[0010] According to the invention (2), a vehicle can be provided that can reduce noise generated when the valves are operated during start-up of the vehicle.

[0011] (3) A vehicle described in (1) or (2), wherein the control device requests the valve to be switched from the closed state to the open state when the oil temperature of the automatic transmission oil is equal to or higher than a predetermined temperature, and when the valve is in the closed state and the oil temperature of the automatic transmission oil becomes equal to or higher than the predetermined temperature after the vehicle has stopped, the control device switches the valve to the open state when the approach notification system is activated.

[0012] According to the invention (3), it is possible to provide a vehicle that can reduce noise during valve operation when the temperature of the automatic transmission oil becomes equal to or higher than a predetermined temperature after the vehicle has stopped.

[0013] (4) A vehicle as described in any one of (1) to (3), in which, when the specified conditions are met, the operating sound of the approach warning system is increased compared to when the specified conditions are not met.

[0014] According to the invention (4), noise generated when the valve used to cool the automatic transmission oil is operated can be further reduced.

[0015] (5) The vehicle according to (4), wherein, if the predetermined condition is met before the approach notification system is activated, the operating sound of the approach notification system is increased.

[0016] According to the invention (5), noise generated when the valve used to cool the automatic transmission oil is operated can be further reduced.

[0017] (6) A vehicle as described in (4) or (5), in which an increase in the operating sound of the approach notification system is prohibited if the specified condition is not met while the approach notification system is operating.

[0018] According to the invention (6), unnecessary increase in the operating noise of the approach notification system can be suppressed. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a block diagram showing the configuration of a refrigerant circuit according to an embodiment of the present invention. [Figure 2] FIG. 10 is a diagram showing the relationship between the vehicle speed and load of the vehicle, and the FDU oil temperature and FSV operation according to one embodiment of the present invention. [Figure 3] FIG. 2 is a flow diagram illustrating the control logic of a valve according to an embodiment of the present invention. [Figure 4] 4 is a graph showing the relationship between the vehicle speed, AVAS output, and solenoid valve permission flag of a vehicle according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] An embodiment of the present invention will be described below with reference to the drawings, but the present invention is not limited to the description of the embodiment below.

[0021] The vehicle according to this embodiment has a coolant flow path through which coolant for cooling the drive source flows, and a heat exchanger that exchanges heat between the coolant and the ATF. The vehicle according to this embodiment may be equipped with an electric motor 20 described below as a drive source, or may be equipped with an internal combustion engine and the electric motor 20 as drive sources.

[0022] Fig. 1 is a block diagram showing the configuration of a refrigerant circuit 1 provided in a vehicle according to one embodiment of the present invention. As shown in Fig. 1, the refrigerant circuit 1 according to this embodiment is mounted on a vehicle V, and includes an internal combustion engine ICE, a control unit (ECU) 10, an electric motor 20, a generator 30, a transmission 40, a power conversion device 50, a temperature control circuit 60, an FDU (front drive unit) 70, and an AVAS (acoustic vehicle alerting system) 80.

[0023] The electric motor 20 is a rotating electric machine that outputs power to drive the vehicle V using electric power stored in a power storage device (not shown) mounted on the vehicle V or electric power generated by a generator 30. The electric motor 20 is provided with a temperature sensor 20a that detects the temperature of the electric motor 20. The temperature sensor 20a outputs a detected value of the temperature of the electric motor 20 to the control device 10.

[0024] The generator 30 is a rotating electric machine that generates electricity using the power of the internal combustion engine ICE, and charges the above-mentioned power storage device or supplies electric power to the electric motor 20.

[0025] The transmission 40 is a device that reduces the speed of the power output from the electric motor 20 and transmits it to the drive wheels, and is, for example, a gear-type power transmission device.

[0026] The power conversion device 50 converts the power output from the power storage device from DC to AC. The power converter 50 is provided with a temperature sensor 50a that detects the temperature of the power converter 50. The temperature sensor 50a outputs the detected value of the temperature of the power converter 50 to the control device 10.

[0027] The FDU (front drive unit) 70 is a unit that includes the electric motor 20, the generator 30, and the transmission 40. The electric motor 20, the generator 30, and the transmission 40 that make up the FDU 70 are circulated with ATF (automatic fluid) which will be described later, and which lubricates the gears and cools the equipment.

[0028] The temperature control circuit 60 has an ATF oil passage 61 through which ATF (Automatic Transmission Fluid) circulates and controls the temperatures of the electric motor 20, the generator 30, and the transmission 40, a cooling water passage 62 through which cooling water circulates and controls the temperature of the power conversion device 50, and a heat exchanger 63 that exchanges heat between the ATF and the cooling water. The ATF is an oil that can lubricate and control the temperatures of the electric motor 20, the generator 30, and the transmission 40.

[0029] The ATF oil passage 61 is provided with a first pump 611 and a storage section 612. The first pump 611 is a mechanical pump driven by the power of the internal combustion engine ICE and the rotational force of an axle (not shown) of the vehicle V. The first pump 611 is configured so that its rotation speed is adjusted by adjusting the electric power supplied thereto, and its discharge capacity is continuously variable. The storage section 612 stores the ATF circulating through the ATF oil passage 61. The storage section 612 is, for example, an oil pan provided at the bottom of a housing (not shown) that accommodates the electric motor 20, the generator 30, and the transmission 40. The ATF oil passage 61 has a branch section 613. The ATF oil passage 61 includes a pressure-feeding passage 610a having a first pump 611, an upstream end connected to a reservoir 612, a downstream end connected to a branch 613 through the first pump 611, a first branch passage 610b1 having an electric motor 20 and a generator 30, an upstream end connected to the branch 613, a downstream end connected to the reservoir 612 through the electric motor 20 and the generator 30, and a second branch passage 610b2 having a transmission 40, an upstream end connected to the branch 613, a downstream end connected to the reservoir 612 through the transmission 40. In the ATF oil passage 61, the heat exchanger 63 is disposed upstream of the electric motor 20 and the generator 30 in the first branch passage 610b1.

[0030] The coolant flow path 62 is provided with a second pump 621 and a radiator 622. The second pump 621 is, for example, an electric pump driven by electricity stored in the above-mentioned power storage device. The radiator 622 is disposed at the front of the vehicle V, and is a heat dissipation device that cools the coolant by wind generated when the vehicle V is traveling.

[0031] Coolant flow path 62 has a branching portion 624 and a junction portion 625. In the coolant flow path, a second pump 621 and a radiator 622 are provided in this order from the upstream side, and the coolant flow path has a pressure flow path 620a whose upstream end is connected to the junction portion 625, passes through second pump 621 and radiator 622, and has a downstream end connected to branching portion 624. Coolant is pressure-fed by second pump 621 through pressure flow path 620a and cooled by radiator 622.

[0032] Coolant flow path 62 further includes a branch flow path 620b1, which is provided with power conversion device 50 and has an upstream end connected to branch portion 624, passes through power conversion device 50, and has a downstream end connected to junction 625, and an ATF flow path 620b2, which is provided with heat exchanger 63 and has an upstream end connected to branch portion 624, passes through heat exchanger 63, and has a downstream end connected to junction 625. A flow shut valve 626, which is a valve switchable between a closed state that closes ATF flow path 620b2 and an open state that opens ATF flow path 620b2, is provided in a portion of ATF flow path 620b2 upstream of heat exchanger 63.

[0033] The flow shut valve 626 is, for example, a normally open solenoid valve that is in an open state in which the ATF flow path 620b2 is open when not energized. The normally open flow shut valve 626 can be switched to a closed state in which the ATF flow path 620b2 is closed when energized. The flow shut valve 626 can be switched between a closed state and an open state in response to a command from the control device 10. The flow shut valve 626 may be a normally closed solenoid valve, but is preferably a normally open type in terms of preventing sticking, etc. Hereinafter, the flow shut valve 626 will be described as a normally open solenoid valve.

[0034] The flow shut valve 626 has a valve portion that opens and closes the flow path, and a drive portion that drives the valve portion. The valve portion is composed of a valve element, a valve seat, etc. When the flow shut valve 626 is switched from a closed state to an open state, the valve element comes into contact with the components that make up the flow path, generating valve operating noise. When the flow shut valve 626 is switched from an open state to a closed state, the drive portion generates valve operating noise. For example, if the valve element and the components that make up the flow path are made of a resin such as fluororesin, and the drive portion is made of a metal, etc., the operating noise when the flow shut valve 626 is switched from an open state to a closed state will be louder than the operating noise when it is switched from a closed state to an open state.

[0035] In pressure-feeding passage 620a, the coolant is pumped by second pump 621 and cooled by radiator 622, and then branches into branch passage 620b1 and ATF passage 620b2 at branching point 624. The coolant flowing through branch passage 620b1 cools power conversion device 50 and merges with ATF passage 620b2 and pressure-feeding passage 620a at junction 625. The coolant flowing through ATF passage 620b2 cools the ATF by exchanging heat with heat exchanger 63, and then merges with branch passage 620b1 and pressure-feeding passage 620a at junction 625. The coolant that has flowed through branch passage 620b1 and ATF passage 620b2 is supplied again to second pump 621 through pressure-feeding passage 620a, and the coolant circulates through coolant passage 62.

[0036] The AVAS 80 is a system that emits an operating sound (alarm sound) such as a simulated engine sound from a speaker to alert pedestrians and others around the vehicle of an approaching vehicle while the vehicle is running using the electric motor 20. The AVAS 80 is controlled by the control device 10 to emit an operating sound, for example, when the vehicle runs at a predetermined speed (e.g., 25 km / h) or less after starting, when the vehicle is decelerated and runs at a predetermined speed (e.g., 25 km / h) or less, or when a parking range (reverse) operation is performed while the vehicle is running using the electric motor 20.

[0037] The vehicle according to this embodiment further includes a rotation sensor capable of detecting the engine rotation speed, which is the rotation speed of the input shaft of the torque converter, a vehicle speed sensor that detects the vehicle speed, a sensor that detects the air conditioning air flow rate, and the like.

[0038] The control device 10 controls the internal combustion engine ICE, the power conversion device 50, the second pump 621, and the flow shut valve 626. Furthermore, the control device 10 adjusts the power supply to the second pump 621 and controls the opening and closing of the flow shut valve 626 based on the detection results of the above sensors. The control device 10 also controls the generation of operating noise by the AVAS 80. Below, details of the control of the second pump 621, the flow shut valve 626, and the AVAS 80 performed by the control device 10 will be described.

[0039] The control device 10 issues a switching request to switch between a closed state and an open state of the flow shut valve 626, so that the flow shut valve 626 is closed when the oil temperature falls below a predetermined oil temperature at which fuel economy is achieved through reduced ATF friction, and is opened when the oil temperature exceeds a predetermined oil temperature determined by a drive source cooling request. The control device 10 controls the flow shut valve 626 to switch when the above predetermined conditions are met, and also when the condition that the AVAS 80 is operating is met. As a result, the operating sound of the flow shut valve 626 is masked by the operating sound of the AVAS 80, thereby reducing noise caused by the flow shut valve 626.

[0040] FIG. 2 shows an example of the relationship between the vehicle speed and the load on the drive source including the electric motor 20, the oil temperature of the FDU 70, and the operation of the flow shut valve 626 when the vehicle is traveling at low speed. First, immediately after the drive source is started (IG on), the oil temperature of the FDU 70 is low. Therefore, it is necessary to increase the oil temperature of the ATF. If the flow shut valve 626 is a normally open type, the flow shut valve 626 is in an open state before start-up, so it is preferable to switch the flow shut valve 626 from the open state to the closed state soon after start-up. At this time, it is preferable that the operating sound of the AVAS 80 masks the operating sound of the flow shut valve 626.

[0041] Next, during low-speed driving, such as when driving in an urban area, the oil temperature of the FDU is still in the low-oil-temperature / heat-accumulation period. During this period, a low load continues, and therefore the flow shut valve 626 remains closed. Next, during high-speed driving, such as when driving in suburban / high-speed areas (in the case of a hybrid vehicle, the vehicle is driven by the internal combustion engine), and immediately after high-speed driving, a suitable-temperature / cooling / heat-up switching period occurs. During this period, a cooling request (switching request) is made if the ATF oil temperature exceeds a predetermined temperature, and a heating request (switching request) is made if the ATF oil temperature falls below the predetermined temperature, and the flow shut valve 626 switches between the closed and open states as appropriate. Next, when the vehicle stops or drives at a low speed after a high load, the FDU 70 may receive heat due to a rise in the temperature of the drive source, such as the internal combustion engine, and the ATF oil temperature may rise, even though the load is low (the dashed line in Figure 2). At this time, a request may be made to switch the flow shut valve 626 from a closed state to an open state, and in this case too, it is preferable that the operating sound of the flow shut valve 626 be masked by the operating sound of the AVAS 80.

[0042] Next, an example of a control routine of the control device 10 for masking the operating sound of the flow shut valve 626 with the operating sound of the AVAS 80 will be described with reference to the flow chart of FIG.

[0043] 3 detects the vehicle speed (Vsp) and the parking shift range after the vehicle starts, and if certain requirements are met, causes the AVAS 80 to emit an operating sound. Then, while the AVAS 80 is operating, the flow shut valve 626 is switched from a closed state to an open state (step S1).

[0044] Next, the control routine determines whether the vehicle remains stopped (step S2). If the vehicle remains stopped, the control routine proceeds to step S7, where operation (switching) of flow shut valve 626 is prohibited. If the vehicle does not remain stopped, the control routine proceeds to step S3.

[0045] Next, the control routine detects the FDU oil temperature (step S3) and determines whether or not there is a request to switch the flow shut valve 626 (step S4). If there is a request to switch the flow shut valve 626, the process proceeds to step S5. If there is no request to switch the flow shut valve 626, the process proceeds to step S3.

[0046] Next, the control routine determines whether the AVAS 80 is operating (step S5). If the AVAS 80 is operating, the process proceeds to step S6, where the operation (switching) of the flow shut valve 626 is permitted. If the AVAS 80 is not operating, the process proceeds to step S7, where the operation (switching) of the flow shut valve 626 is prohibited.

[0047] The control routine may be executed only when the vehicle speed is below a predetermined speed (e.g., 25 km / h). This is because when the vehicle speed exceeds the predetermined speed (e.g., 25 km / h), the AVAS 80 does not operate and the operating noise of the flow shut valve 626 does not pose a problem.

[0048] In the above control routine, it is preferable that the sound pressure (dB) of the operating sound emitted from AVAS 80 when there is a request to switch flow shut valve 626 is higher than usual. This improves the masking effect of AVAS 80 on the operating sound of flow shut valve 626.

[0049] In the above control routine, if a request to switch the flow shut valve 626 occurs before the AVAS 80 operates, it is preferable to increase the sound pressure (dB) of the operating noise of the AVAS 80 more than usual when the AVAS 80 operates. This can further improve the effect of the AVAS 80 in masking the operating noise of the flow shut valve 626.

[0050] In the above control routine, if there is no request to switch the flow shut valve 626 while the AVAS 80 is operating, it is preferable to prohibit an increase in the sound pressure (dB) of the operating noise of the AVAS 80. This makes it possible to prevent unnecessary increases in the operating noise of the AVAS 80.

[0051] Next, the relationship between the vehicle speed, the AVAS output, and the solenoid valve permission flag issued by the above control routine will be described with reference to FIG.

[0052] 4, the vertical axis of each graph represents, from top to bottom, the vehicle speed, the AVAS output, and the solenoid valve enable flag, and the horizontal axis of each graph represents the elapsed time.

[0053] As shown in Figure 4, after time T0 when the vehicle starts moving, vehicle speed Vsp increases, which in turn increases AVAS output and the operating noise of AVAS 80. At time T11 after AVAS output reaches a predetermined threshold, a permission flag is issued to switch the solenoid valve (flow shut valve) from an open state to a closed state. The permission flag remains in effect until time T12 when vehicle speed Vsp exceeds a predetermined vehicle speed (25 km / h).

[0054] Next, after time T2 when the vehicle speed Vsp falls below a predetermined speed (25 km / h), the AVAS output increases accordingly. At time T21 after the AVAS output reaches a predetermined threshold, a solenoid valve permission flag is set to permit switching of the solenoid valve (flow shut valve). The solenoid valve permission flag remains set until time T3 when the vehicle speed Vsp exceeds the predetermined speed (25 km / h). Similarly, after time T4 when the vehicle speed Vsp falls below the predetermined speed (25 km / h), the solenoid valve permission flag is set again at time T41 after the AVAS output reaches the predetermined threshold, and remains set until time T5.

[0055] The times h1, h2, and h3 during which the solenoid valve enable flag is set are shorter than the time during which vehicle speed Vsp is equal to or lower than a predetermined vehicle speed, and the solenoid valve enable flag is set after AVAS output reaches a predetermined threshold. As a result, the flow shut valve 626 is switched with increased operating noise from AVAS 80, so that the AVAS 80 can effectively mask the operating noise of flow shut valve 626. [Explanation of symbols]

[0056] 10 ECU (control unit) 62 Cooling water flow path 620b2 ATF flow path 626 Flow Shut Valve (Valve) 63 Heat exchange equipment 80 AVAS (Approach Alert System) V vehicle

Claims

1. a cooling water flow path through which cooling water flows; A vehicle having a heat exchanger that exchanges heat between the cooling water and the automatic transmission oil, the coolant flow path has an ATF flow path connected to the heat exchange device and allowing the coolant to flow through the heat exchange device; a valve that can be switched between a closed state that closes the ATF flow path and an open state that opens the ATF flow path is provided in the ATF flow path, a control device that switches the valve to the closed state or the open state when a predetermined condition is satisfied; The control device switches the valve to the closed state or the open state when the predetermined condition is met and an approach notification system is activated.

2. the valve is normally open; 2. The vehicle according to claim 1, wherein the control device prohibits the valve from being switched to the closed state after the vehicle is started and until the approach notification system is activated, and switches the valve to the closed state when the approach notification system is activated.

3. The control device When the temperature of the automatic transmission fluid is equal to or higher than a predetermined temperature, a switching request is made to switch the valve from the closed state to the open state, 3. The vehicle according to claim 1, wherein if the valve is in the closed state, and if the vehicle does not remain stopped after stopping, and if the oil temperature of the automatic transmission oil reaches or exceeds a predetermined temperature, the valve is switched to the open state when the approach notification system is activated.

4. 4. The vehicle according to claim 1, wherein when the predetermined condition is satisfied, an operating sound of the approach notification system is increased compared to when the predetermined condition is not satisfied.

5. The vehicle according to claim 4, wherein, if the predetermined condition is satisfied before the approach warning system is activated, an operating sound of the approach warning system is increased.

6. 6. The vehicle according to claim 4, wherein an increase in the operating sound of the approach warning system is prohibited if the predetermined condition is not satisfied while the approach warning system is in operation.

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