JP2019138369A - Working fluid supply device - Google Patents

Abstract

To reduce production cost of a working fluid supply device.SOLUTION: A working fluid supply device 100 includes: a first oil pump 10 driven by an engine 50; a second oil pump 20 driven by an electric motor 60; and a discharge part 30 which can discharge a hydraulic oil discharged from the first oil pump 10 with respect to at least one out of a suction side of the first oil pump 10, the suction side of the second oil pump 20 and an automatic transmission 70. The discharge part 30 includes: a discharge passage 32 communicating with at least one out of the suction side of the first oil pump 10, the suction side of the second oil pump 20 and the inside of the automatic transmission 70; and an unloading valve 35 for allowing the discharge passage 32 to discharge the hydraulic oil discharged from the first oil pump 10 by opening the valve.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a working fluid supply device that controls supply of a working fluid to a power transmission device for a vehicle.

  Patent Document 1 discloses a working fluid supply device including a mechanical pump driven by an engine and an electric pump driven by an electric motor. The mechanical pump of this working fluid supply apparatus is connected to the engine via a clutch, and by disengaging the clutch, the load that drives the mechanical pump is not applied to the engine, thereby reducing fuel consumption in the engine. It is possible to suppress.

JP 2000-46166 A

  However, in general, the clutch mechanism has a complicated structure and is expensive, and requires a relatively large installation space. For this reason, in an apparatus that employs a clutch mechanism, such as the working fluid supply apparatus described in Patent Document 1, there is a possibility that the manufacturing cost may increase and the entire apparatus may be increased in size.

  The present invention has been made in view of the above problems, and an object of the present invention is to reduce the manufacturing cost of the working fluid supply device and to make the entire device compact.

  According to a first aspect of the present invention, there is provided a power transmission device in which a working fluid supply device that controls supply of a working fluid to a power transmission device that transmits an output of a first drive source to driving wheels of a vehicle is driven by the output of the first drive source. A first pump capable of supplying a working fluid to a second pump, a second pump driven by an output of a second drive source and capable of supplying a working fluid to a power transmission device, a suction side of the first pump, a suction side of the second pump, And at least one of the interiors of the power transmission device, a discharge part capable of discharging the working fluid discharged from the first pump, wherein the discharge part is a suction side of the first pump, a second pump And a discharge passage communicating with at least one of the inside of the power transmission device, and a release valve for releasing the working fluid discharged from the first pump into the discharge passage by opening the valve. Features.

  In the first invention, by discharging the working fluid discharged from the first pump to any of the suction side of the first pump, the suction side of the second pump, and the inside of the power transmission device through the release valve, It is possible to make a state in which a load for driving the first pump is not applied to the first drive source. Thus, the discharge valve used to bring the first pump into the no-load operation state is structurally simple and inexpensive. For this reason, the manufacturing cost of the working fluid supply apparatus can be reduced and the entire apparatus can be made compact.

  According to a second aspect of the present invention, the discharge unit further includes a switching valve that switches a communication destination of the discharge passage according to an operating state of the second pump or the power transmission device.

  In the second invention, the communication destination of the discharge passage is switched by the switching valve. Therefore, by appropriately switching the switching valve, the working fluid discharged through the release valve requires the working fluid among the suction side of the first pump, the suction side of the second pump, and the inside of the power transmission device. Priority can be given to the site.

  According to a third aspect of the present invention, the working fluid supply device further includes a switching control unit that controls switching of the switching valve, and the switching control unit has a discharge flow rate of the second pump that exceeds a predetermined flow rate. When the determination is made, the switching valve is controlled so that the discharge passage communicates with at least the suction side of the second pump.

  In the third invention, when the discharge flow rate of the second pump exceeds a predetermined flow rate, the switching valve is controlled so that the discharge passage communicates with the suction side of the second pump. As a result, part of the working fluid discharged into the discharge passage is guided to the suction side of the second pump. Thus, by returning a part of the discharged working fluid to the suction side of the second pump, the suction negative pressure generated on the suction side of the second pump is reduced, and the occurrence of cavitation due to the suction negative pressure is suppressed. Can do.

  According to a fourth aspect of the present invention, the working fluid supply device further includes a switching control unit that controls switching of the switching valve, and the switching control unit is configured to release the discharge passage when an increase in temperature inside the power transmission device is predicted. Is characterized in that the switching valve is controlled so as to communicate with at least the interior of the power transmission device.

  In the fourth invention, when the temperature inside the power transmission device is rising, the switching valve is controlled such that the discharge passage communicates with the inside of the power transmission device. Thereby, a part of working fluid discharged | emitted by the discharge | release channel | path is guide | induced to the inside of a power transmission device. In this way, by releasing a part of the released working fluid toward the inside of the power transmission device, it becomes possible to cool or lubricate the inside of the power transmission device, and as a result, seize in the inside of the power transmission device. Can be prevented.

  The fifth invention is characterized in that the discharge passage is always in communication with the suction side of the first pump.

  In the fifth invention, the discharge passage is always in communication with the suction side of the first pump. Thereby, the working fluid discharged from the first pump is guided to the suction side of the first pump by opening the release valve. By returning the working fluid discharged from the first pump to the suction side of the first pump in this way, the suction negative pressure generated on the suction side of the first pump is reduced, and the occurrence of cavitation due to the suction negative pressure is suppressed. Can do.

  The sixth invention is characterized in that the discharge passage always communicates with the suction side of the second pump.

  In the sixth invention, the discharge passage always communicates with the suction side of the second pump. Thereby, the working fluid discharged from the first pump is guided to the suction side of the second pump by opening the release valve. Thus, by returning the working fluid discharged from the first pump to the suction side of the second pump, the suction negative pressure generated on the suction side of the second pump is reduced, and the occurrence of cavitation due to the suction negative pressure is suppressed. Can do.

  The seventh invention is characterized in that the discharge passage always communicates with the inside of the power transmission device.

  In the seventh invention, the discharge passage is always in communication with the inside of the power transmission device. Thereby, the working fluid discharged from the first pump is guided to the inside of the power transmission device by opening the release valve. By discharging the working fluid discharged from the first pump toward the inside of the power transmission device in this way, the inside of the power transmission device can be cooled or lubricated, and as a result, seizure occurs inside the power transmission device. Can be prevented.

  The eighth invention is characterized in that the discharge passage communicates with the inside of the power transmission device according to the temperature inside the power transmission device.

  In the eighth invention, the discharge passage communicates with the inside of the power transmission device according to the temperature inside the power transmission device. For this reason, it is possible to prevent seizure from occurring inside the power transmission device by guiding the working fluid to the inside of the power transmission device, while the need to cool or lubricate the inside of the power transmission device is low. By guiding the working fluid to the suction side of the first pump and the second pump, the occurrence of cavitation in the suction portions of the first pump and the second pump can be suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to reduce the manufacturing cost of a working fluid supply apparatus, the whole apparatus can be reduced in size.

It is the schematic which shows the structure of the working fluid supply apparatus which concerns on 1st Embodiment of this invention. It is a block diagram for demonstrating the function of the controller of the working fluid supply apparatus which concerns on 1st Embodiment of this invention. It is a flowchart which shows the control procedure performed by the controller of the working fluid supply apparatus which concerns on 1st Embodiment of this invention. It is the schematic which shows the structure of the 1st modification of the working fluid supply apparatus which concerns on 1st Embodiment of this invention. It is the schematic which shows the structure of the 2nd modification of the working fluid supply apparatus which concerns on 1st Embodiment of this invention. It is the schematic which shows the structure of the 3rd modification of the working fluid supply apparatus which concerns on 1st Embodiment of this invention. It is the schematic which shows the structure of the working fluid supply apparatus which concerns on 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

<First Embodiment>
FIG. 1 is a schematic diagram showing a configuration of a working fluid supply apparatus 100 according to the first embodiment of the present invention. The working fluid supply device 100 is mounted on a vehicle (not shown) including an engine 50 as a first drive source and an automatic transmission 70 as a power transmission device that transmits the output of the engine 50 to drive wheels. The supply of the working fluid to 70 is controlled. Below, the case where the automatic transmission 70 is a transmission provided with a belt-type continuously variable transmission mechanism (CVT) will be described as an example.

  The working fluid supply device 100 is driven by the output of the engine 50, and the first oil pump 10 as a first pump capable of supplying the working oil as the working fluid to the automatic transmission 70, and the electric motor 60 as the second drive source. The second oil pump 20 as a second pump that is driven by the output of the first oil pump 10 and can supply the hydraulic oil to the automatic transmission 70, and the hydraulic oil discharged from the first oil pump 10, the suction side of the first oil pump 10, 2. Supply state of hydraulic oil to the automatic transmission 70 by controlling the operation of the discharge portion 30 that can be discharged to the suction side of the oil pump 20 and the inside of the automatic transmission 70, and the electric motor 60 and the discharge portion 30 And a controller 40 for controlling.

  The first oil pump 10 is a vane pump that is rotationally driven by the engine 50, sucks the hydraulic oil stored in the tank 16 through the suction pipe 11, and discharges the hydraulic oil to the automatic transmission 70 through the discharge pipe 12. The discharge pipe 12 is provided with a check valve 14 that allows only the flow of hydraulic oil from the first oil pump 10 to the automatic transmission 70.

  The second oil pump 20 is an internal gear pump that is rotationally driven by the electric motor 60, sucks the hydraulic oil stored in the tank 16 through the suction pipe 21, and is connected to the discharge pipe 12 of the first oil pump 10. The hydraulic oil is discharged to the automatic transmission 70 through the discharge pipe 22. The discharge pipe 22 is provided with a check valve 24 that allows only the flow of hydraulic oil from the second oil pump 20 to the automatic transmission 70.

  The rotation of the electric motor 60 that drives the second oil pump 20 is controlled by the controller 40. For this reason, the discharge flow rate of the second oil pump 20 can be freely changed by changing the rotation of the electric motor 60.

  As described above, in the working fluid supply device 100, the working oil can be supplied to the automatic transmission 70 from the two pumps of the first oil pump 10 and the second oil pump 20.

  The discharge unit 30 includes a branch passage 31 branched from the discharge pipe 12 connected to the discharge side of the first oil pump 10 on the upstream side of the check valve 14, and an outlet as a discharge valve connected to the branch passage 31. It has a load valve 35 and a discharge passage 32 connected to the downstream side of the unload valve 35. The branch passage 31 and the discharge passage 32 communicate with each other when the unload valve 35 is opened.

  The discharge passage 32 includes a first discharge passage 33 that guides hydraulic oil to the suction side of the first oil pump 10 and the second oil pump 20, and a second discharge passage 34 that guides hydraulic oil to the inside of the automatic transmission 70. Branch to,.

  The first discharge passage 33 includes a first suction side passage 33a that guides hydraulic oil to the suction side of the first oil pump 10, and a second suction side passage 33b that guides hydraulic oil to the suction side of the second oil pump 20. , Further branches. Specifically, the first suction side passage 33 a is connected to the suction pipe 11 of the first oil pump 10, and the second suction side passage 33 b is connected to the suction pipe 21 of the second oil pump 20. In addition, the connection destination of the 1st suction side channel | path 33a and the 2nd suction side channel | path 33b is not restricted to the suction pipes 11 and 21, For example, the tank 16 may be sufficient. However, as will be described later, in order to reduce the suction negative pressure generated on the suction side of the first oil pump 10 and the second oil pump 20, a position close to the suction port of the first oil pump 10 and the second oil pump 20 is used. It is preferable to connect the first suction side passage 33a and the second suction side passage 33b to each other.

  The first suction side passage 33a is provided with a first on-off valve 36 as a switching valve capable of opening or closing the first suction side passage 33a, and the second suction side passage 33b is provided with a second suction side passage. A second on-off valve 37 is provided as a switching valve that can open or shut off 33b.

  The second release passage 34 opens inside the automatic transmission 70 toward a portion where cooling or lubrication is required, such as a contact portion between a pulley of a variator of a belt type continuously variable transmission mechanism (not shown) and a metal belt. ing. The second release passage 34 is provided with a third on-off valve 38 as a switching valve capable of opening or closing the second release passage 34.

  The unload valve 35 and the first to third open / close valves 36, 37, and 38 are electrically driven open / close valves, and the opening / closing of these is controlled by the controller 40. The unload valve 35 and the first to third on-off valves 36, 37, and 38 may be of direct acting type in which the valve body is directly driven by a solenoid to open and close each passage, or pilot pressure that acts on the valve body. It may be of a pilot type that opens and closes each passage according to the presence or absence of the valve, and may have any configuration as long as each passage can be opened and closed according to a command from the controller 40. Of the unloading valve 35 and the first to third on-off valves 36, 37, and 38, for example, the on-off valve that is normally open like the first on-off valve 36 provided in the first suction side passage 33a. A normally open type is preferably employed, and a normally closed type is preferably employed for an on-off valve that is normally closed like the unload valve 35.

  In a state where the unload valve 35 is closed, the communication between the branch passage 31 and the discharge passage 32 is interrupted, so that the hydraulic oil discharged from the first oil pump 10 passes to the automatic transmission 70 through the discharge pipe 12. Supplied. On the other hand, when the unload valve 35 is opened, the branch passage 31 and the discharge passage 32 communicate with each other, so that the hydraulic oil discharged from the first oil pump 10 is discharged to the discharge passage 32 through the unload valve 35. Is done.

  If the first on-off valve 36 is in the open state when the unload valve 35 is opened, the hydraulic oil discharged to the discharge passage 32 passes through the first discharge passage 33 and the first suction side passage 33a. It is discharged to the suction side of the first oil pump 10. Similarly, if the second on-off valve 37 is in the opened state, the hydraulic oil discharged to the discharge passage 32 is transferred to the suction side of the second oil pump 20 through the first discharge passage 33 and the second suction side passage 33b. It is guided.

  If the third on-off valve 38 is opened when the unload valve 35 is opened, the hydraulic oil discharged to the discharge passage 32 passes through the second discharge passage 34 to the automatic transmission 70. The mechanism that is discharged inside and cools or lubricates the mechanism that constitutes the automatic transmission 70.

  That is, when the unload valve 35 is opened, the hydraulic oil discharged from the first oil pump 10 passes through the branch passage 31 and the discharge passage 32, and the suction side of the first oil pump 10 and the suction side of the second oil pump 20. , And any one of the insides of the automatic transmission 70.

  As described above, when the unload valve 35 is opened and the hydraulic oil discharged from the first oil pump 10 is guided to a region where the pressure is relatively low, the pressure on the discharge side of the first oil pump 10 is reduced. As a result, the pressure difference between the suction side and the discharge side of the first oil pump 10 approaches zero.

Therefore, in the working fluid supply apparatus 100, the unload valve 35 is opened and closed so that the first oil pump 10 is loaded and unloaded, that is, the load that drives the first oil pump 10 is applied to the engine 50. Thus, it is possible to switch between this state and a state in which the load for driving the first oil pump 10 is hardly applied to the engine 50. In the working fluid supply device 100, the first to third on-off valves 36, 37, 38 are provided. By controlling the open / closed state of the hydraulic oil, the hydraulic oil discharged to the discharge passage 32 through the unload valve 35 is supplied to the suction side of the first oil pump 10, the suction side of the second oil pump 20, or the automatic transmission 70. It is possible to selectively lead to any of the inside.

  Next, the controller 40 will be described with reference to FIG. FIG. 2 is a block diagram for explaining the function of the controller 40.

  The controller 40 is constituted by a microcomputer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an I / O interface (input / output interface). The RAM stores data in the processing of the CPU, the ROM stores in advance a CPU control program and the like, and the I / O interface is used for input / output of information with a device connected to the controller 40. The controller 40 may be composed of a plurality of microcomputers.

  The controller 40 supplies hydraulic oil to the automatic transmission 70 by controlling the electric motor 60 and the unload valve 35 based on signals indicating the state of the vehicle input from various sensors provided in each part of the vehicle. In addition to functioning as a supply state control unit to control, it also functions as a switching control unit that switches and controls the first to third on-off valves 36, 37, and 38 according to the operating states of the electric motor 60 and the automatic transmission 70. The controller 40 may serve as the controller of the engine 50 and the controller of the automatic transmission 70, or may be provided separately from the controller of the engine 50 and the controller of the automatic transmission 70.

  Examples of the signal indicating the state of the vehicle input to the controller 40 include a signal indicating the speed of the vehicle, a signal indicating the acceleration of the vehicle, a signal indicating the operation position of the shift lever, a signal indicating the operation amount of the accelerator, and the engine 50. , A signal indicating the load of the engine 50 such as a throttle opening and a fuel injection amount, a signal indicating the input shaft and output shaft rotational speeds of the automatic transmission 70, and hydraulic oil in the automatic transmission 70 A signal indicating the temperature, a signal indicating the pressure (line pressure) of hydraulic oil supplied to the automatic transmission 70, a signal indicating the transmission ratio of the automatic transmission 70, a signal indicating the discharge pressure of the first oil pump 10, and a second A signal indicating the discharge pressure of the oil pump 20, a signal indicating the number of rotations of the electric motor 60, and the like.

  The controller 40 needs to calculate the required flow rate Qr of hydraulic fluid required by the automatic transmission 70 based on signals input from various sensors as a function for controlling the supply of hydraulic fluid to the automatic transmission 70. The flow rate calculation unit 41, the discharge flow rate calculation unit 42 for calculating the discharge flow rate Q1 of the hydraulic oil discharged from the first oil pump 10 based on signals input from various sensors, and the necessary flow rate calculation unit 41 require calculation. The first comparison unit 43 that compares the flow rate Qr with the discharge flow rate Q1 calculated by the discharge flow rate calculation unit 42, and calculates the driving power W1 of the first oil pump 10 based on signals input from various sensors and the required flow rate A driving power calculation unit 44 that calculates the driving power W2 of the second oil pump 20 when the target discharge flow rate Qa set based on Qr is discharged, and the driving power calculation unit 4 Based on the comparison result of the second comparison unit 45 that compares the driving power W1 of the first oil pump 10 and the driving power W2 of the second oil pump 20 calculated in step S1 and the first comparison unit 43 and the second comparison unit 45. And a supply state setting unit 46 for setting a supply state of hydraulic oil to the automatic transmission 70. In addition, these required flow volume calculating parts 41 grade | etc., Showed each function of the controller 40 as a virtual unit, and does not mean that it exists physically.

  The required flow rate calculation unit 41 mainly includes the accelerator opening and the vehicle speed, the oil temperature of the hydraulic oil in the automatic transmission 70, the pressure of the hydraulic oil supplied to the automatic transmission 70, the input shaft and the output shaft of the automatic transmission 70. Based on the number of revolutions and the gear ratio of the automatic transmission 70, the flow rate of hydraulic oil required by the automatic transmission 70 is calculated.

  Here, the flow rate of the hydraulic oil required for the automatic transmission 70 is a shift flow rate required for changing the pulley width of a variator of a belt-type continuously variable transmission mechanism (not shown), a clearance in the hydraulic control valve, and a hydraulic pressure. There are a leak flow rate leaking from a gap on the circuit, a lubrication flow rate required for cooling or lubricating the automatic transmission 70, a cooling flow rate guided to an oil cooler (not shown), and the like.

  The flow rate of these flow rates is mapped in advance and stored in the ROM of the controller 40. Specifically, when the gear ratio changes greatly, for example, when the acceleration opening rate is large, or when the vehicle speed deceleration rate is large, the shift flow rate becomes a large value. Is a parameter. Note that, as a parameter related to acceleration / deceleration of the vehicle, a throttle opening, a fuel injection amount, or the like that affects changes in the rotational speed of the engine 50 or a load may be used. The leak flow rate increases as the temperature of the hydraulic oil increases and the viscosity of the hydraulic oil decreases, and as the pressure of the supplied hydraulic oil increases, so the temperature and pressure of the hydraulic oil are parameters. .

  Further, as the temperature of the hydraulic oil rises and the viscosity of the hydraulic oil decreases, the oil film is more likely to break. Therefore, the higher the hydraulic oil temperature, the more the lubrication flow rate needs to be increased, and the rotation within the automatic transmission 70 Since the oil film breakage is more likely to occur as the rotational speed of the shaft is higher, it is necessary to increase the lubricating flow rate as the rotational speed of the rotational shaft in the automatic transmission 70 is higher. Taking these into account, the lubrication flow rate is, for example, the temperature of the hydraulic oil or the rotation speed of the input / output shaft of the automatic transmission 70 as parameters.

  In addition, the temperature of the hydraulic oil must not exceed a predetermined temperature from the standpoint of lubricity and oil film retention. In order to cool the hydraulic oil, cooling air is introduced to the oil cooler. It is necessary to be in a state where the vehicle is driven, that is, a state where the vehicle travels at a vehicle speed higher than a predetermined speed. For this reason, the temperature of the hydraulic oil and the vehicle speed are mainly used as parameters for the cooling flow rate. The parameters for determining the shift flow rate, the leak flow rate, the lubrication flow rate, and the cooling flow rate are examples, and parameters related to the exemplified parameters may be used. The signal is appropriately selected from the signals input to 40.

  As described above, the required flow rate calculation unit 41 calculates the required flow rate Qr of the hydraulic oil required in the automatic transmission 70 in consideration of the shift flow rate, the leak flow rate, the lubrication flow rate, and the cooling flow rate.

  The discharge flow rate calculation unit 42 calculates the discharge flow rate Q1 of the hydraulic oil discharged from the first oil pump 10 mainly based on the rotational speed of the engine 50.

  The rotational speed of the first oil pump 10 and the discharge flow rate Q1 of the first oil pump 10 have a relationship that changes substantially proportionally. The discharge flow rate Q1 of the first oil pump 10 has a viscosity that varies depending on the oil temperature, It changes according to the discharge pressure of the first oil pump 10. These relationships are mapped in advance in order to accurately calculate the discharge flow rate Q1 of the first oil pump 10, and are stored in the ROM of the controller 40.

  Since the rotational speed of the first oil pump 10 changes according to the rotational speed of the engine 50 that drives the first oil pump 10, the discharge flow rate calculation unit 42 determines the rotational speed of the engine 50, the oil temperature of the hydraulic oil, 1 The discharge flow rate Q1 is easily calculated from the discharge pressure of the oil pump 10. The discharge flow rate Q1 of the first oil pump 10 is calculated regardless of the operating state of the unload valve 35, that is, regardless of whether the first oil pump 10 is in a load operation state or a no-load operation state. Note that the discharge flow rate Q1 may be calculated using the rotation speed of the first oil pump 10 instead of the rotation speed of the engine 50. In addition, since the discharge pressure of the first oil pump 10 changes according to the line pressure that is the pressure of the hydraulic oil supplied to the automatic transmission 70, the calculation of the discharge flow rate Q1 of the first oil pump 10 Instead of the discharge pressure of the 1 oil pump 10, a line pressure may be used.

  The first comparison unit 43 compares the required flow rate Qr calculated by the required flow rate calculation unit 41 with the discharge flow rate Q1 calculated by the discharge flow rate calculation unit 42, and if the discharge flow rate Q1 is greater than or equal to the required flow rate Qr. Then, the comparison result signal is transmitted to the drive power calculation unit 44, and when the discharge flow rate Q1 is smaller than the required flow rate Qr, the comparison result signal is transmitted to the supply state setting unit 46.

  When receiving the comparison result signal from the first comparison unit 43, the drive power calculation unit 44 calculates the drive power W1 of the first oil pump 10 and discharges the target discharge flow rate Qa set based on the required flow rate Qr. In this case, the driving power W2 of the second oil pump 20 is calculated.

  The drive power W1 of the first oil pump 10 is an output spent for driving the first oil pump 10 in the engine 50, and the discharge flow rate Q1, the discharge pressure P1, and the pump efficiency η1 of the first oil pump 10 And calculated from When the first oil pump 10 is in a no-load operation state and hydraulic oil is not supplied from the first oil pump 10 to the automatic transmission 70, the line pressure PL that is the pressure of the hydraulic oil in the automatic transmission 70 is set. Assuming the discharge pressure P1, the drive power W1 of the first oil pump 10 is estimated. The pump efficiency η1 that changes according to the rotation speed of the first oil pump 10, the discharge pressure P1, and the oil temperature of the hydraulic oil is mapped in advance and stored in the ROM of the controller 40. Note that the value calculated by the discharge flow rate calculation unit 42 is used as the discharge flow rate Q1.

  Similarly, the driving power W2 of the second oil pump 20 is calculated from the target discharge flow rate Qa of the second oil pump 20, the discharge pressure P2, and the pump efficiency η2. The target discharge flow rate Qa is a flow rate that is about 10% higher than the required flow rate Qr calculated by the required flow rate calculation unit 41, and has a margin so as not to fall below the required flow rate Qr even if the current vehicle state slightly changes. Is set. When the electric motor 60 is stopped and the hydraulic oil is not supplied from the second oil pump 20 to the automatic transmission 70, the line pressure PL, which is the pressure of the hydraulic oil in the automatic transmission 70, is set to the discharge pressure P2. Assuming that the driving power W2 of the second oil pump 20 is estimated. The pump efficiency η2 that changes in accordance with the rotation speed of the second oil pump 20, the discharge pressure P2, and the oil temperature of the hydraulic oil is mapped in advance in the same manner as the pump efficiency η1 of the first oil pump 10, and the ROM of the controller 40 Is remembered. The driving power W2 of the second oil pump 20 corresponds to the power consumed in the electric motor 60 that drives the second oil pump 20, and therefore the second oil pump 20 is driven based on the current and voltage supplied to the electric motor 60. The driving power W2 of the pump 20 may be calculated.

  Here, electric power generated by an alternator driven by the engine 50 is supplied to the electric motor 60 via a battery. For this reason, in order to make the drive condition of the 1st oil pump 10 and the drive condition of the 2nd oil pump 20 correspond, in calculating the drive power W2 of the 2nd oil pump 20, the power generation efficiency of an alternator and the charge / discharge efficiency of a battery And various other energy conversion efficiencies. That is, the drive power W2 of the second oil pump 20 that is finally calculated is an output that is consumed in the engine 50 when it is assumed that the second oil pump 20 is driven by the engine 50.

  The calculation method of the driving power W1 of the first oil pump 10 and the driving power W2 of the second oil pump 20 is not limited to the calculation method described above, and the driving conditions of the first oil pump 10 and the second oil pump 20 Any calculation method may be used as long as the drive power W1 of the first oil pump 10 and the drive power W2 of the second oil pump 20 are calculated when the drive conditions are the same. For example, when the discharge pressure P1 and the discharge pressure P2 are not directly detected, the line pressure PL is assumed to be the discharge pressure P1 and the discharge pressure P2 regardless of the supply state of the hydraulic oil. The driving power W1, W2 may be calculated.

  The second comparison unit 45 compares the drive power W1 of the first oil pump 10 calculated by the drive power calculation unit 44 with the drive power W2 of the second oil pump 20, and sends a comparison result signal to the supply state setting unit 46. Send.

  The supply state setting unit 46 sets the supply state of hydraulic oil to the automatic transmission 70 based on the comparison result signal transmitted from the first comparison unit 43 and the second comparison unit 45. Specifically, when the supply state setting unit 46 receives a signal from the second comparison unit 45 that the drive power W1 of the first oil pump 10 is equal to or less than the drive power W2 of the second oil pump 20, the supply state setting unit 46 turns the electric motor 60 on. By stopping or maintaining the electric motor 60 in a stopped state, the above-described supply state is set to the first supply state in which the hydraulic oil is supplied from only the first oil pump 10 to the automatic transmission 70.

  When the signal indicating that the driving power W1 of the first oil pump 10 is larger than the driving power W2 of the second oil pump 20 is received from the second comparison unit 45, the supply state setting unit 46 opens the unload valve 35. As a result, the first oil pump 10 is brought into a no-load operation state, and the above-described supply state is set to the second supply state in which the hydraulic oil is supplied from only the second oil pump 20 to the automatic transmission 70.

  In addition, when the signal that the discharge flow rate Q1 is smaller than the required flow rate Qr is received from the first comparison unit 43, the supply state setting unit 46 closes the unload valve 35 and drives the electric motor 60 to The above-described supply state is set to the third supply state in which hydraulic oil is supplied from both the first oil pump 10 and the second oil pump 20 to the automatic transmission 70.

  In addition to the functions described above, the controller 40 includes a drive state determination unit 47 that determines the drive state of the engine 50 based on signals input from various sensors, the first oil pump 10 and the drive state determination unit 47 based on signals input from the various sensors. An abnormality determination unit 48 that determines whether or not the second oil pump 20 is abnormal.

  The drive state determination unit 47 determines what drive state the engine 50 is in, based on the rotation speed, throttle opening, fuel injection amount, etc. of the engine 50, particularly whether it is stopped or being driven. judge. The result determined by the drive state determination unit 47 is transmitted to the supply state setting unit 46 as a determination result signal.

  When the supply state setting unit 46 receives a signal from the drive state determination unit 47 that the engine 50 is in a stopped state, the supply state setting unit 46 enters the second supply state in which the hydraulic oil is supplied from only the second oil pump 20 to the automatic transmission 70. Set the supply status. As a result, even when the first oil pump 10 is not driven by the engine 50, such as when idling is stopped, the hydraulic oil can be supplied to the automatic transmission 70 by the second oil pump 20.

  The abnormality determination unit 48 mainly includes the line pressure PL, which is the pressure of the hydraulic oil supplied to the automatic transmission 70, the discharge pressure P1 of the first oil pump 10, the discharge pressure P2 of the second oil pump 20, and the temperature of the hydraulic oil. Based on the above, it is determined whether there is an abnormality in the first oil pump 10 and the second oil pump 20. For example, the abnormality determination unit 48 determines that the abnormality of the first oil pump 10 occurs when the line pressure PL or the discharge pressure P1 of the first oil pump 10 is not within a predetermined range when the first oil pump 10 is being driven. If the line pressure PL or the discharge pressure P2 of the second oil pump 20 is not within a predetermined range when the second oil pump 20 is driven, it is determined that the second oil pump 20 is abnormal.

  Further, the abnormality determination unit 48 is in a state where the temperature of the hydraulic oil is very low, for example, minus 20 degrees or less, and if the second oil pump 20 is driven by the electric motor 60, the viscosity of the hydraulic oil is high. When there is a possibility that the electric motor 60 is overloaded, it is determined that the second oil pump 20 is abnormal. When the temperature of the hydraulic oil is very low, idling stop control is prohibited, and the hydraulic oil is constantly supplied from the first oil pump 10 to the automatic transmission 70.

  In addition, the abnormality determination unit 48 can drive the electric motor 60 normally even when the amount of charge of the battery that supplies power to the electric motor 60 is insufficient or when the alternator that charges the battery with generated power is abnormal. Since there is a possibility of disappearing, it is determined that the second oil pump 20 is abnormal.

  When the supply state setting unit 46 receives a signal from the abnormality determination unit 48 that the first oil pump 10 is abnormal, the supply state setting unit 46 supplies the hydraulic oil to the automatic transmission 70 only from the second oil pump 20. When the above-mentioned supply state is set and a signal indicating that the second oil pump 20 is abnormal is received from the abnormality determination unit 48, the unload valve 35 is closed and only the first oil pump 10 is operated to the automatic transmission 70. The above-described supply state is set as the second abnormal-time supply state for supplying oil.

  The supply state setting unit 46 controls the electric motor 60 in the first abnormal supply state so that the discharge flow rate Q2 of the second oil pump 20 reaches the required flow rate Qr of hydraulic oil required by the automatic transmission 70. The rotational speed of the electric motor 60 is increased.

  Further, the supply state setting unit 46 automatically turns off when the discharge flow rate Q1 of the first oil pump 10 is smaller than the required flow rate Qr of hydraulic oil required by the automatic transmission 70 in the second abnormal supply state. The speed of the engine 50 is increased by controlling the transmission 70 to slightly change the gear ratio to the low side, so that the discharge flow rate Q1 of the first oil pump 10 reaches the required flow rate Qr. Increase the speed. On the other hand, when the discharge flow rate Q1 of the first oil pump 10 is equal to or higher than the required flow rate Qr of hydraulic oil required by the automatic transmission 70 in the second abnormal supply state, the supply state setting unit 46 Only the unload valve 35 is closed without controlling the automatic transmission 50 and the automatic transmission 70. As a result, even when there is an abnormality in the first oil pump 10 or the second oil pump 20, it is possible to sufficiently supply hydraulic oil to the automatic transmission 70, and the automatic transmission 70 is stably operated. be able to.

  When the rotational speed of the engine 50 that drives the first oil pump 10 reaches the maximum rated rotational speed or when the rotational speed of the electric motor 60 that drives the second oil pump 20 reaches the upper limit rotational speed, There is a risk that the required flow rate Qr of hydraulic oil required by the automatic transmission 70 cannot be secured. In such a case, the required flow rate Qr of the automatic transmission 70 may be reduced by controlling the engine 50 and reducing the output torque of the engine 50 to reduce the required line pressure PL.

  Next, the supply control of the hydraulic oil to the automatic transmission 70 by the controller 40 having the above-described function will be described with reference to the flowchart of FIG. The control shown in FIG. 3 is repeatedly executed by the controller 40 every predetermined time.

  First, in step S <b> 11, detection signals from various sensors indicating the state of the vehicle, in particular, the state of the engine 50 and the automatic transmission 70 are input to the controller 40.

  In step S12, the required flow rate calculation unit 41 calculates the required flow rate Qr of hydraulic fluid required by the automatic transmission 70 based on the signals of the various sensors input in step S11.

  In subsequent step S13, the discharge flow rate calculation unit 42 calculates the discharge flow rate Q1 of the hydraulic oil discharged from the first oil pump 10 based on the signals of the various sensors input in step S11.

  The required flow rate Qr calculated in step S12 and the discharge flow rate Q1 calculated in step S13 are compared by the first comparison unit 43 in step S14.

  In step S14, when it is determined that the discharge flow rate Q1 is equal to or higher than the required flow rate Qr, that is, it is possible to cover the required flow rate Qr of the hydraulic oil required by the automatic transmission 70 only by the first oil pump 10. If there is, the process proceeds to step S15. On the other hand, when it is determined that the discharge flow rate Q1 is smaller than the required flow rate Qr, that is, the first oil pump 10 alone cannot cover the required flow rate Qr of hydraulic oil required by the automatic transmission 70. In the case, the process proceeds to step S19.

  In step S15, the drive power calculation unit 44 calculates the drive power W1 of the first oil pump 10 and the drive power W2 of the second oil pump 20 based on the signals of the various sensors input in step S11.

  The drive power W1 of the first oil pump 10 and the drive power W2 of the second oil pump 20 calculated by the drive power calculator 44 are compared by the second comparator 45 in step S16.

  Here, since the first oil pump 10 is driven by the engine 50, the discharge flow rate Q1 thereof increases as the rotational speed of the engine 50 increases. On the other hand, the required flow rate Qr of the hydraulic oil required for the automatic transmission 70 increases when the gear ratio changes greatly, that is, when the accelerator opening rate increases greatly or when the vehicle speed deceleration rate is large. However, when the change in the vehicle speed is small, it becomes relatively small.

  That is, when the rotational speed of the engine 50 is relatively high and the vehicle speed is relatively stable, the discharge flow rate Q1 exceeds the required flow rate Qr, and the amount of oil supplied to the automatic transmission 70 is excessive. Therefore, as a result, the output of the engine 50 is wasted to drive the first oil pump 10. In such a case, rather than driving the first oil pump 10, the fuel discharge in the engine 50 is suppressed when the second oil pump 20 discharges the target discharge flow rate Qa that exceeds the required flow rate Qr by a predetermined amount. May be possible.

  Specifically, the engine 50 rotates in the middle rotation range or higher where the rotational speed is relatively high and the vehicle is in a cruise operation state where the change in the vehicle speed is small, or the engine 50 is in the high rotation range due to engine braking. And when it is rotating. Even when the engine 50 has a low rotation speed, the required flow rate of the automatic transmission 70 is maintained when the vehicle is stopped and the engine 50 is idling or when the vehicle is traveling due to a creep phenomenon. Since Qr becomes very small, the discharge flow rate Q1 of the first oil pump 10 may exceed the required flow rate Qr. Even in such a situation, when the oil temperature is high, the leakage flow rate and the cooling flow rate increase, so the discharge flow rate Q1 of the first oil pump 10 does not necessarily exceed the required flow rate Qr.

  That is, in step S16, the fuel consumption of the engine 50 is reduced when the second oil pump 20 is driven and hydraulic oil is supplied rather than when the first oil pump 10 is driven and hydraulic oil is supplied. It is determined whether or not

  In step S16, when it is determined that the drive power W1 of the first oil pump 10 is equal to or less than the drive power W2 of the second oil pump 20, that is, the first oil pump 10 is driven by the engine 50 to supply hydraulic oil. If it is possible to reduce the fuel consumption of the engine 50, the process proceeds to step S17, and the supply state of the hydraulic oil to the automatic transmission 70 is set to the first supply state by the supply state setting unit 46. The

  On the other hand, when it is determined in step S16 that the driving power W1 of the first oil pump 10 is larger than the driving power W2 of the second oil pump 20, that is, the second oil pump 20 is driven by the electric motor 60 to operate. If the fuel consumption of the engine 50 can be reduced when the oil is supplied, the process proceeds to step S18, and the supply state of the hydraulic oil to the automatic transmission 70 is set to the second supply state by the supply state setting unit 46. Set to

  In step S <b> 19, the supply state of hydraulic oil to the automatic transmission 70 is set to the third supply state by the supply state setting unit 46. In this case, the required flow rate Qr of hydraulic oil required by the automatic transmission 70 is relatively large, and in order to ensure this, the second oil pump 20 is driven in addition to the first oil pump 10.

  Specifically, as such a situation, when the shift flow rate increases due to sudden acceleration or sudden deceleration, or when the oil temperature of the hydraulic oil becomes high, for example, exceeding 130 ° C., and the leakage flow rate increases, the hydraulic fluid The oil temperature is high, the vehicle speed becomes medium speed (30 to 50 km / h) or more, and it is necessary to secure a sufficient cooling flow rate.

  As described above, sufficient hydraulic oil is supplied to the automatic transmission 70 by switching the supply state of the hydraulic oil to the automatic transmission 70 based on the state of the vehicle, particularly the state of the engine 50 and the automatic transmission 70. At the same time, wasteful fuel consumption in the engine 50 is suppressed. As a result, the automatic transmission 70 can be operated stably and the fuel consumption of the vehicle can be improved.

  If the supply state of the hydraulic oil to the automatic transmission 70 is frequently switched, the pressure of the hydraulic oil supplied to the automatic transmission 70 may fluctuate and the control of the automatic transmission 70 may become unstable. Therefore, when the first comparison unit 43 and the second comparison unit 45 perform comparison, hysteresis may be set to suppress frequent switching of the supply state. In addition, after setting to any supply state, if the amount of hydraulic oil supplied to the automatic transmission 70 does not fall below the required flow rate Qr, it is prohibited to shift to another supply state for a predetermined time. May be.

  Further, when idling stop control is performed in order to reduce the fuel consumption of the engine 50, if the drive state determination unit 47 determines that the engine 50 is in a stopped state, the flowchart shown in FIG. 3 is not followed. The supply state of the hydraulic oil to the automatic transmission 70 is set by the supply state setting unit 46 to the second supply state, that is, the state in which the hydraulic oil is supplied to the automatic transmission 70 only from the second oil pump 20.

  Thus, even when the engine 50 is stopped and the first oil pump 10 is not driven, the hydraulic oil can be stably supplied to the automatic transmission 70 by the second oil pump 20. Note that the required flow rate Qr of the hydraulic oil required by the automatic transmission 70 when the idling stop control is performed is very small, and therefore can be sufficiently covered by the second oil pump 20. Thus, since the second oil pump 20 can be used as a spare electric oil pump that is driven when idling is stopped, it is not necessary to separately provide a spare electric oil pump, thereby reducing the manufacturing cost of the vehicle. Can do. In the case of a vehicle that already has a spare electric oil pump, it is not necessary to provide a new electric oil pump by setting the performance of the auxiliary electric oil pump to be equivalent to that of the second oil pump 20. The manufacturing cost of the vehicle can be reduced.

  If the abnormality determination unit 48 determines that there is an abnormality in the first oil pump 10 or the second oil pump 20, the controller 40 does not follow the flowchart shown in FIG. In this state, hydraulic oil is supplied to the automatic transmission 70.

  Specifically, when the supply state setting unit 46 receives a signal from the abnormality determination unit 48 that the first oil pump 10 is abnormal, the supply state setting unit 46 changes the supply state of supplying hydraulic oil to the automatic transmission 70 to the second oil pump. 20 is set to a first abnormality supply state in which hydraulic oil is supplied from only 20, and the electric motor 60 is controlled so that the discharge flow rate Q2 of the second oil pump 20 is required for the automatic transmission 70. The rotational speed of the electric motor 60 is increased so as to reach the flow rate Qr.

  When the supply state setting unit 46 receives a signal from the abnormality determination unit 48 that the second oil pump 20 is abnormal, the supply state setting unit 46 closes the unload valve 35 in a supply state in which hydraulic oil is supplied to the automatic transmission 70. In addition, the engine 50 is controlled and the discharge flow rate Q1 of the first oil pump 10 is required for the automatic transmission 70 while the second oil supply state is set so that hydraulic oil is supplied only from the first oil pump 10. The rotational speed of the engine 50 is increased so that the required flow rate Qr of oil is reached.

  As a result, even when there is an abnormality in the first oil pump 10 or the second oil pump 20, it is possible to sufficiently supply hydraulic oil to the automatic transmission 70, and the automatic transmission 70 is stably operated. be able to.

  Next, switching control of the first to third on-off valves 36, 37, and 38 of the discharge unit 30 performed by the controller 40 will be described.

  As described above, when the supply state of the hydraulic oil to the automatic transmission 70 is set to the second supply state, the controller 40 is discharged from the first oil pump 10 by opening the unload valve 35. The hydraulic oil is discharged into the discharge passage 32 and the second oil pump 20 is driven by the electric motor 60 so that the hydraulic oil is supplied from the second oil pump 20 to the automatic transmission 70.

  When the unload valve 35 is opened, the controller 40 normally opens only the first on-off valve 36. Thereby, the hydraulic oil discharged to the discharge passage 32 is guided to the suction side of the first oil pump 10 through the first discharge passage 33 and the first suction side passage 33a. Thus, by returning the total amount of hydraulic oil discharged from the first oil pump 10 to the suction side of the first oil pump 10, the pressure difference between the suction side and the discharge side of the first oil pump 10 is substantially zero. It becomes possible to do. As a result, the first oil pump 10 is in a no-load operation state, that is, a state in which the load for driving the first oil pump 10 is hardly applied to the engine 50. For this reason, when it is not necessary to drive the first oil pump 10, it is possible to prevent the engine 50 from consuming unnecessary fuel.

  Further, by returning the hydraulic oil discharged from the first oil pump 10 to the suction side of the first oil pump 10, the suction negative pressure generated on the suction side of the first oil pump 10 is reduced, and cavitation due to the suction negative pressure is reduced. Generation | occurrence | production can be suppressed and it can prevent that erosion arises around the suction part of the 1st oil pump 10 with generation | occurrence | production of cavitation.

  Next, the case where the controller 40 opens the second on-off valve 37 in the switching control will be described.

  As the discharge flow rate Q2 of the second oil pump 20 increases, the suction negative pressure generated on the suction side of the second oil pump 20 also increases. When the suction negative pressure increases, cavitation occurs and erosion may occur in the vicinity of the suction portion of the second oil pump 20 with the occurrence of cavitation.

  In order to suppress the occurrence of such cavitation and erosion, the controller 40 determines that the discharge flow rate Q2 of the second oil pump 20 has exceeded a predetermined first discharge flow rate Qc1, and the second on-off valve 37 is opened. Thereby, a part of the hydraulic oil discharged to the discharge passage 32 is guided to the suction side of the second oil pump 20 through the first discharge passage 33 and the second suction side passage 33b. In this way, by returning a part of the hydraulic oil discharged from the first oil pump 10 to the suction side of the second oil pump 20, the suction negative pressure generated on the suction side of the second oil pump 20 is reduced, and the suction Generation of cavitation due to negative pressure is suppressed, and erosion can be prevented from occurring around the suction portion of the second oil pump 20.

  Here, the magnitude of the suction negative pressure generated on the suction side of the second oil pump 20 increases as the discharge flow rate Q2 of the second oil pump 20 increases, and cavitation and erosion occur as the suction negative pressure increases. It becomes easy. Therefore, when the controller 40 determines that the discharge flow rate Q2 of the second oil pump 20 is greater than the first discharge flow rate Qc1 and exceeds the second discharge flow rate Qc2 where cavitation is more likely to occur, the first discharge flow rate Q2 is determined. The on-off valve 36 is closed. As a result, the entire amount of hydraulic oil discharged to the discharge passage 32 is guided to the suction side of the second oil pump 20 through the first discharge passage 33 and the second suction side passage 33b. In this way, by introducing the entire amount of hydraulic oil discharged from the first oil pump 10 to the suction side of the second oil pump 20, the suction negative pressure generated on the suction side of the second oil pump 20 is reduced, and cavitation occurs. And the occurrence of erosion is suppressed.

  Whether or not the discharge flow rate Q2 of the second oil pump 20 exceeds the first discharge flow rate Qc1 or the second discharge flow rate Qc2 is determined by directly measuring the discharge flow rate of the second oil pump 20. Alternatively, it may be performed based on the predicted discharge flow rate of the second oil pump 20 estimated from the rotational speed of the electric motor 60 that drives the second oil pump 20. The first discharge flow rate Qc1 and the second discharge flow rate Qc2 are preset threshold values, and are stored in the ROM of the controller 40.

  Next, the case where the controller 40 opens the third on-off valve 38 in the switching control will be described.

  In the automatic transmission 70, for example, the contact pressure at the contact portion between the pulley of the variator and the metal belt is high when the engine 50 is in a high-speed and high-load running state in which the engine 50 is operated at a relatively high load and a high rotation speed, or an engine brake. As a result, torque is transmitted from the wheel side to the engine 50 and the engine 50 is raised when the engine 50 is rotating in a relatively high rotation range. When the contact pressure increases in this way, there is a possibility that seizure occurs due to the occurrence of oil film breakage or heat generation.

  In order to prevent the occurrence of such burn-in, the controller 40 opens the third on-off valve 38 when an increase in the temperature inside the automatic transmission 70 is predicted. As a result, part of the hydraulic oil discharged into the discharge passage 32 is guided to the inside of the automatic transmission 70 through the second discharge passage 34. As described above, by releasing a part of the hydraulic oil discharged from the first oil pump 10 toward the inside of the automatic transmission 70, for example, the contact portion between the pulley and the metal belt, the inside of the automatic transmission 70 is obtained. As a result, it is possible to prevent seizure from occurring inside the automatic transmission 70.

  The increase in the temperature inside the automatic transmission 70 may be obtained by directly measuring the temperature inside the automatic transmission 70, for example, the temperature of the hydraulic oil, or is transmitted via the vehicle speed or the automatic transmission 70. It may be estimated on the basis of the magnitude of the load to be received. When the temperature increase in the automatic transmission 70 is predicted to be very large, the first on-off valve 36 is closed, and the entire amount of hydraulic oil discharged from the first oil pump 10 is automatically shifted. It may be discharged inside the machine 70. Thereby, it is possible to more reliably prevent seizure from occurring inside the automatic transmission 70.

  According to the above 1st Embodiment, there exists an effect shown below.

  In the working fluid supply device 100, the working oil discharged from the first oil pump 10 through the unload valve 35 is used as the suction side of the first oil pump 10, the suction side of the second oil pump 20, and the automatic transmission 70. By discharging to any of the inside, it is possible to prevent the engine 50 from being loaded with the load that drives the first oil pump 10. The unload valve 35 that is used to bring the first oil pump 10 into the no-load operation state is structurally simple and is relatively inexpensive. For this reason, the manufacturing cost of the working fluid supply apparatus 100 can be reduced and the entire apparatus can be made compact.

  Next, a modification of the first embodiment will be described. The modifications described below are also within the scope of the present invention, and the configurations shown in these modifications and the structures described in the first embodiment are combined, or the modifications described later and the first embodiment described above are described. It is also possible to combine the configuration with the configuration and modification described in the second embodiment described later.

  Further, in the first embodiment, the first oil pump 10 and the second oil pump 20 suck the working oil from the tank 16 through the suction pipes 11 and 21, respectively. Instead, as in the first modification shown in FIG. 4, the suction pipe 21 of the second oil pump 20 is connected to the suction pipe 11 of the first oil pump 10, and the first oil pump 10 and the second oil pump 10 are connected. The suction pipe may be shared by the pump 20. In this case, since the second on-off valve 37 that is controlled when the hydraulic oil discharged to the discharge passage 32 is guided to the suction side of the second oil pump 20 can be eliminated, the manufacturing cost of the working fluid supply apparatus 100 can be reduced. The working fluid supply device 100 can be simplified while being able to be reduced.

  Further, in the first embodiment, the hydraulic oil discharged from the first oil pump 10 is discharged to the discharge passage 32 by opening the unload valve 35 connected to the branch passage 31. Instead, as in the second modification shown in FIG. 5, the first unload valve 35a and the second unload valve 35b provided in the first discharge passage 33 and the second discharge passage 34 are opened. By doing so, the hydraulic oil discharged from the first oil pump 10 may be discharged to the first discharge passage 33 and the second discharge passage 34.

  In this way, by making the first unload valve 35a and the second unload valve 35b function not only as a release valve but also as a switching valve, an on-off valve as a switching valve can be eliminated. For this reason, the manufacturing cost of the working fluid supply apparatus 100 can be reduced. In this case, when the hydraulic oil discharged from the first oil pump 10 is discharged to the discharge side of the first oil pump 10 and the second oil pump 20, the first unload valve 35a is opened, and the automatic The second unload valve 35b is opened when releasing into the transmission 70, and the first unload valve 35a and the second unload valve 35b are opened when releasing both.

  In the first embodiment, the unload valve 35 connected to the branch passage 31 is opened to release the hydraulic oil discharged from the first oil pump 10 to the discharge passage 32, and the first to third The hydraulic oil discharge destination is switched by opening and closing the on-off valves 36, 37, and 38. Instead of this, an unload control valve 35c having a function of switching the discharge destination may be adopted as the discharge valve and the switching valve as in the third modification shown in FIG.

  A first discharge passage 33 and a second discharge passage 34 are connected to the downstream side of the unload control valve 35c, and the unload control valve 35c is connected to the branch passage 31, the first discharge passage 33, and the second discharge passage 34. A blocking position that blocks communication with the first discharge path 33, a first communication position that connects the branch passage 31 and the first discharge passage 33, and a second discharge passage 34 that communicates with the branch passage 31 in addition to the first discharge passage 33. 2 communication positions.

  The unload control valve 35c has a proportional solenoid and a spool valve driven by the proportional solenoid, and the position of the unload control valve 35c depends on the current supplied to the proportional solenoid. And the second communication position. In addition, it is good also as a structure which changes gradually the ratio which connects the 2nd discharge passage 34 to the branch passage 31 from a 1st communication position to a 2nd communication position by adjusting the electric current supplied to a proportional solenoid.

  As described above, the first to third on-off valves 36, 37, and 38 can be eliminated by causing the unload control valve 35c to function not only as a discharge valve but also as a switching valve. For this reason, the manufacturing cost of the working fluid supply apparatus 100 can be reduced and the working fluid supply apparatus 100 can be simplified. As in the first embodiment, the first on-off valve 36 and the second on-off valve 37 are provided in the first suction side passage 33a and the second suction side passage 33b, respectively, to further switch the discharge destination of the hydraulic oil. It is good also as a possible structure.

  In the first embodiment, the case where the automatic transmission 70 is a transmission including a belt-type continuously variable transmission mechanism (CVT) has been described. However, the automatic transmission 70 operates using the pressure of hydraulic oil. Any type may be used, and a toroidal continuously variable transmission mechanism or planetary gear mechanism may be used.

  In the first embodiment, the first oil pump 10 is a vane pump, and the second oil pump 20 is an internal gear pump. The types of the first oil pump 10 and the second oil pump 20 do not have to be different types, and the same type may be used. For example, both may be vane pumps. Moreover, the form of the pump is not limited to these, and may be any form as long as it is a positive displacement pump such as an external gear pump or a piston pump. The first oil pump 10 is a fixed capacity type, but may be a variable capacity type pump.

  In the first embodiment, the first oil pump 10 is driven by the output of the engine 50. The first drive source that drives the first oil pump 10 is not limited to the engine 50, and may be, for example, an electric motor that drives the drive wheels of the vehicle.

  In the first embodiment, the second oil pump 20 is driven by the output of the electric motor 60. The second drive source that drives the second oil pump 20 is not limited to the electric motor 60, and may be, for example, an auxiliary engine that drives an auxiliary machine or the like.

  Further, in the first embodiment, various signals are listed as signals indicating the state of the vehicle input to the controller 40. In addition, for example, a torque converter is provided in the automatic transmission 70. If there is, a signal indicating the operating state or the fastening state of the torque converter may be input to the controller 40. In this case, the required flow rate Qr of the automatic transmission 70 may be calculated in consideration of the state of the torque converter, or the switching of the supply state of hydraulic oil to the automatic transmission 70 may be limited. For example, when it is detected that the torque converter is in a semi-engaged state (slip lock-up state), the hydraulic oil supply state may be prohibited from shifting to another supply state. Thereby, the torque converter can be maintained in a stable operating state. Further, a signal indicating the brake operation amount and the operation speed may be input to the controller 40 as a signal indicating the deceleration state of the vehicle.

  In the first embodiment, the discharge flow rate calculation unit 42 of the controller 40 calculates the discharge flow rate Q1 of the hydraulic oil discharged from the first oil pump 10. Instead of this, the actual discharge flow rate Q1 of the hydraulic oil discharged from the first oil pump 10 may be directly measured by a flow rate sensor or the like.

Second Embodiment
Next, with reference to FIG. 7, the working fluid supply apparatus 200 which concerns on 2nd Embodiment of this invention is demonstrated. Below, it demonstrates centering on a different point from 1st Embodiment, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment, and description is abbreviate | omitted.

  The basic configuration of the working fluid supply apparatus 200 is the same as that of the working fluid supply apparatus 100 according to the first embodiment. The working fluid supply device 200 is different from the working fluid supply device 100 in that the discharge unit 130 is not provided with an on-off valve as a switching valve.

  The discharge unit 130 of the working fluid supply apparatus 200 is connected to the branch passage 31 branched from the discharge pipe 12, the unload valve 35 as a discharge valve connected to the branch passage 31, and the downstream side of the unload valve 35. A discharge passage 32. The branch passage 31 and the discharge passage 32 communicate with each other when the unload valve 35 is opened.

  The discharge passage 32 includes a first discharge passage 33 that guides hydraulic oil to the suction side of the first oil pump 10 and the second oil pump 20, and a second discharge passage 34 that guides hydraulic oil to the inside of the automatic transmission 70. Branch to,.

  The first discharge passage 33 includes a first suction side passage 33a that guides hydraulic oil to the suction side of the first oil pump 10, and a second suction side passage 33b that guides hydraulic oil to the suction side of the second oil pump 20. , Further branches. Specifically, the first suction side passage 33 a is connected to the suction pipe 11 of the first oil pump 10, and the second suction side passage 33 b is connected to the suction pipe 21 of the second oil pump 20.

  The second discharge passage 34 is opened in the automatic transmission 70 toward a portion where cooling or lubrication is required, such as a contact portion between a pulley of a variator of a belt type continuously variable transmission mechanism and a metal belt. . The second discharge passage 34 is provided with a temperature-sensitive on-off valve 138 whose valve opening amount changes according to the temperature inside the automatic transmission 70, for example, the temperature of the hydraulic oil flowing inside the automatic transmission 70.

  The temperature-sensitive on-off valve 138 has a bimetal that deforms according to the temperature of the hydraulic oil and a valve body that displaces according to the deformation of the bimetal, and the valve opening amount increases as the temperature of the hydraulic oil increases. Set to In addition, as a member which detects the temperature of hydraulic fluid, it is not limited to a bimetal, What kind of thing may be used as long as the valve opening amount can be changed according to temperature. Further, the internal temperature of the automatic transmission 70 is not limited to the temperature of the hydraulic oil, and may be an internal atmospheric temperature or a temperature of a specific member constituting the automatic transmission 70. .

  In the working fluid supply device 200, as in the working fluid supply device 100 in the first embodiment, the communication between the branch passage 31 and the discharge passage 32 is blocked when the unload valve 35 is closed. 1 The hydraulic oil discharged from the oil pump 10 is supplied to the automatic transmission 70 through the discharge pipe 12. On the other hand, when the unload valve 35 is opened, the branch passage 31 and the discharge passage 32 communicate with each other, so that the hydraulic oil discharged from the first oil pump 10 is discharged to the discharge passage 32 through the unload valve 35. Is done.

  Here, the first suction side passage 33 a is always connected to the suction pipe 11 of the first oil pump 10, and the second suction side passage 33 b is always connected to the suction pipe 21 of the second oil pump 20. . Therefore, the hydraulic oil discharged into the discharge passage 32 is guided to the suction side of the first oil pump 10 through the first discharge passage 33 and the first suction side passage 33a, and the first discharge passage 33 and the second suction passage. It is led to the suction side of the second oil pump 20 through the side passage 33b.

  In this way, the hydraulic oil discharged from the first oil pump 10 is returned to the suction side of the first oil pump 10 and the second oil pump 20, thereby generating on the suction side of the first oil pump 10 and the second oil pump 20. By reducing the suction negative pressure, it is possible to suppress the occurrence of cavitation due to the suction negative pressure and to prevent erosion from occurring around the suction portions of the first oil pump 10 and the second oil pump 20 due to the occurrence of cavitation. .

  Further, when the unloading valve 35 is opened, if the temperature of the hydraulic fluid flowing inside the automatic transmission 70 is relatively high and the temperature-sensitive on-off valve 138 is in the opened state, it is discharged into the discharge passage 32. The hydraulic fluid thus discharged is discharged into the automatic transmission 70 through the second discharge passage 34. As a result, a part of the hydraulic oil discharged from the first oil pump 10 is discharged toward the inside of the automatic transmission 70, for example, the contact portion between the pulley and the metal belt. It is possible to cool or lubricate, and as a result, seizure can be prevented from occurring inside the automatic transmission 70.

  On the other hand, when the unload valve 35 is opened, if the temperature of the hydraulic fluid flowing inside the automatic transmission 70 is relatively low and the temperature-sensitive on-off valve 138 is closed, the discharge passage 32 is opened. The discharged hydraulic oil is guided to the suction side of the first oil pump 10 and the second oil pump 20 through the first discharge passage 33 without being guided into the automatic transmission 70. As described above, when the need to cool or lubricate the inside of the automatic transmission 70 is low, the first oil is guided to the suction side of the first oil pump 10 and the second oil pump 20 so that the first oil is introduced. Occurrence of cavitation and erosion in the suction portions of the pump 10 and the second oil pump 20 is suppressed.

  As described above, in the working fluid supply device 200, the hydraulic oil discharged from the first oil pump 10 passes through the branch passage 31 and the discharge passage 32 only by opening the unload valve 35. It is discharged to any one of the suction side, the suction side of the second oil pump 20, and the inside of the automatic transmission 70.

  In the working fluid supply apparatus 200, since the opening / closing valve as the switching valve is not provided in the discharge unit 130, the working fluid supply apparatus 200 can be made compact and the manufacturing cost of the apparatus can be reduced. Further, in the working fluid supply apparatus 200, it is not necessary to perform switching control for switching the connection destination of the discharge passage 32 by the controller 40. Therefore, control when discharging the hydraulic oil discharged from the first oil pump 10 to the discharge passage 32 is performed. Can be simplified.

  Further, in the working fluid supply device 200, as in the working fluid supply device 100 in the first embodiment, when the unload valve 35 is opened, the working oil discharged from the first oil pump 10 has a relatively low pressure. As a result, the pressure on the discharge side of the first oil pump 10 decreases, and as a result, the pressure difference between the suction side and the discharge side of the first oil pump 10 approaches zero.

  Therefore, also in the working fluid supply apparatus 200, the first oil pump 10 can be switched between the load operation state and the no-load operation state by opening and closing the unload valve 35. For this reason, when it is not necessary to drive the first oil pump 10, it is possible to prevent the engine 50 from consuming unnecessary fuel.

  According to the above 2nd Embodiment, there exists an effect shown below.

  In the working fluid supply device 200, the working oil discharged from the first oil pump 10 through the unload valve 35 is used as the suction side of the first oil pump 10, the suction side of the second oil pump 20, and the automatic transmission 70. By discharging to any of the inside, it is possible to prevent the engine 50 from being loaded with the load that drives the first oil pump 10. The unload valve 35 that is used to bring the first oil pump 10 into the no-load operation state is structurally simple and is relatively inexpensive. For this reason, the manufacturing cost of the working fluid supply apparatus 200 can be reduced and the entire apparatus can be made compact.

  Next, a modification of the second embodiment will be described.

  In the second embodiment, the discharge passage 32 is branched into a first discharge passage 33 and a second discharge passage 34. Instead of this, the second discharge passage 34 may be eliminated and only the first discharge passage 33 may be provided. In this case, the entire amount of hydraulic oil discharged to the discharge passage 32 is guided to the suction side of the first oil pump 10 and the second oil pump 20. Further, the second discharge passage 34 may be abolished, and the second suction side passage 33b may be abolished. In this case, the entire amount of hydraulic oil discharged to the discharge passage 32 is guided to the suction side of the first oil pump 10. Similarly, the second discharge passage 34 may be eliminated and the first suction side passage 33a may be eliminated. In this case, the entire amount of hydraulic oil discharged to the discharge passage 32 is guided to the suction side of the second oil pump 20.

  In any of these cases, when the unload valve 35 opens, the hydraulic oil discharged from the first oil pump 10 is guided to a region where the pressure is relatively low, and the suction side and the discharge side of the first oil pump 10 The first oil pump 10 enters a no-load operation state. For this reason, when it is not necessary to drive the first oil pump 10, it is possible to prevent the engine 50 from consuming unnecessary fuel.

  In the second embodiment, a temperature-sensitive on / off valve 138 is provided in the second discharge passage 34. Instead of this, the second discharge passage 34 may be always opened inside the automatic transmission 70 without providing the temperature-sensitive on-off valve 138. In this case, when the unload valve 35 is opened, the hydraulic oil discharged into the discharge passage 32 is discharged into the automatic transmission 70 through the second discharge passage 34. For this reason, the inside of the automatic transmission 70 can be cooled or lubricated, and as a result, it is possible to prevent seizure from occurring inside the automatic transmission 70.

  Further, when the temperature-sensitive on-off valve 138 is not provided in the second discharge passage 34, the first discharge passage 33 may be omitted. In this case, the entire amount of hydraulic oil discharged to the discharge passage 32 is guided into the automatic transmission 70. For this reason, by increasing the flow rate of the working oil that cools or lubricates the inside of the automatic transmission 70, it is possible to more reliably prevent seizure from occurring inside the automatic transmission 70. Also in this case, when the unload valve 35 is opened, the hydraulic oil discharged from the first oil pump 10 is guided to a region where the pressure is relatively low, and the suction side and the discharge side of the first oil pump 10 are The pressure difference approaches zero, and the first oil pump 10 enters a no-load operation state. For this reason, when it is not necessary to drive the first oil pump 10, it is possible to prevent the engine 50 from consuming unnecessary fuel.

  Hereinafter, the configuration, operation, and effect of the embodiment of the present invention will be described together.

  The working fluid supply devices 100, 200 are driven by the output of the engine 50 and can supply hydraulic oil to the automatic transmission 70, and are driven by the output of the electric motor 60 to supply hydraulic oil to the automatic transmission 70. The first oil pump 10 can be supplied to at least one of the second oil pump 20 that can be supplied, the suction side of the first oil pump 10, the suction side of the second oil pump 20, and the inside of the automatic transmission 70. Discharge parts 30 and 130 capable of discharging the hydraulic oil discharged from the discharge parts 30 and 130, the discharge parts 30 and 130 being a suction side of the first oil pump 10, a suction side of the second oil pump 20, and an automatic transmission. 70 and the discharge passages 32, 33, 34 communicating with at least one of the inside of the 70, and the hydraulic oil discharged from the first oil pump 10 is released into the discharge passages 32, 33, 34 by opening the valve. It is to dump valve 35, 35a, a 35b, and 35c, a.

  In this configuration, the hydraulic oil discharged from the first oil pump 10 is discharged through the discharge valves 35, 35a, 35b, and 35c to the suction side of the first oil pump 10, the suction side of the second oil pump 20, and the automatic transmission. It is possible to make it the state where the load which drives the 1st oil pump 10 is not applied to the engine 50 by making it discharge | release to either of the inside of 70. The discharge valves 35, 35a, 35b, and 35c used for bringing the first oil pump 10 into the no-load operation state are structurally simple and relatively inexpensive. For this reason, the manufacturing cost of the working fluid supply devices 100 and 200 can be reduced, and the entire device can be made compact.

  The discharge unit 30 further includes switching valves 35 a, 35 b, 35 c, 36, 37, and 38 that switch communication destinations of the discharge passages 32, 33, and 34 according to the operating state of the second oil pump 20 or the automatic transmission 70. Have.

  In this configuration, the communication destinations of the discharge passages 32, 33, 34 are switched by the switching valves 35a, 35b, 35c, 36, 37, 38. Therefore, by appropriately switching the switching valves 35a, 35b, 35c, 36, 37, and 38, the hydraulic oil released through the release valves 35, 35a, 35b, and 35c is supplied to the suction side of the first oil pump 10, the second The suction side of the oil pump 20 and the inside of the automatic transmission 70 can be preferentially guided to a portion that requires hydraulic oil.

  The working fluid supply apparatus 100 further includes a controller 40 that controls switching of the switching valves 35a, 35b, 35c, 36, 37, and 38. The controller 40 has a predetermined discharge flow rate of the second oil pump 20. If it is determined that the flow rate exceeds the flow rate, the switching valves 35a, 35b, 35c, 36, 37, 38 are set so that the discharge passages 32, 33, 34 communicate with at least the suction side of the second oil pump 20. Control.

  In this configuration, when the discharge flow rate of the second oil pump 20 exceeds a predetermined flow rate, the switching valves 35a, 35b, and 35c are arranged so that the discharge passage 32 communicates with the suction side of the second oil pump 20. , 36, 37, 38 are controlled. Thereby, a part of the hydraulic oil discharged to the discharge passage 32 is guided to the suction side of the second oil pump 20. Thus, by returning a part of the discharged hydraulic oil to the suction side of the second oil pump 20, the suction negative pressure generated on the suction side of the second oil pump 20 is reduced, and the occurrence of cavitation due to the suction negative pressure occurs. Is suppressed, and erosion can be prevented from occurring around the suction portion of the second oil pump 20.

  The working fluid supply apparatus 100 further includes a controller 40 that controls switching of the switching valves 35a, 35b, 35c, 36, 37, and 38, and the controller 40 is predicted to increase the temperature inside the automatic transmission 70. In this case, the switching valves 35a, 35b, 35c, 36, 37, and 38 are controlled so that the discharge passages 32, 33, and 34 communicate with at least the inside of the automatic transmission 70.

  In this configuration, when the temperature inside the automatic transmission 70 is rising, the switching valves 35a, 35b, 35c, 36, 37, and 38 are controlled so that the discharge passage 32 communicates with the inside of the automatic transmission 70. The As a result, part of the hydraulic oil discharged to the discharge passage 32 is guided into the automatic transmission 70. In this way, a part of the discharged hydraulic oil is discharged toward the inside of the automatic transmission 70, for example, the contact portion between the pulley and the metal belt, thereby cooling or lubricating the inside of the automatic transmission 70. As a result, it is possible to prevent seizure from occurring inside the automatic transmission 70.

  Further, the first discharge passage 33 always communicates with the suction side of the first oil pump 10.

  In this configuration, the first discharge passage 33 is always in communication with the suction side of the first oil pump 10. Thus, only by opening the release valves 35, 35 a, and 35 c, part of the hydraulic oil discharged from the first oil pump 10 is guided to the suction side of the first oil pump 10. By returning the hydraulic oil discharged from the first oil pump 10 to the suction side of the first oil pump 10 in this way, the suction negative pressure generated on the suction side of the first oil pump 10 is reduced, and cavitation due to the suction negative pressure is achieved. It is possible to prevent the occurrence of erosion around the suction portion of the first oil pump 10 due to the occurrence of cavitation.

  Further, the first discharge passage 33 always communicates with the suction side of the second oil pump 20.

  In this configuration, the first discharge passage 33 is always in communication with the suction side of the second oil pump 20. Thus, only by opening the release valves 35, 35 a, and 35 c, part of the hydraulic oil discharged from the first oil pump 10 is guided to the suction side of the second oil pump 20. By returning the hydraulic oil discharged from the first oil pump 10 to the suction side of the second oil pump 20 in this way, the suction negative pressure generated on the suction side of the second oil pump 20 is reduced, and cavitation due to the suction negative pressure is achieved. It is possible to prevent the occurrence of erosion around the suction portion of the second oil pump 20 with the occurrence of cavitation.

  The second discharge passage 34 is always in communication with the automatic transmission 70.

  In this configuration, the second discharge passage 34 is always in communication with the inside of the automatic transmission 70. Thus, only by opening the release valves 35, 35 b, 35 c, a part of the hydraulic oil discharged from the first oil pump 10 is guided into the automatic transmission 70. In this way, the hydraulic oil discharged from the first oil pump 10 is discharged into the automatic transmission 70, for example, toward the contact portion between the pulley and the metal belt, thereby cooling or lubricating the inside of the automatic transmission 70. As a result, it is possible to prevent seizure from occurring inside the automatic transmission 70.

  The second discharge passage 34 communicates with the inside of the automatic transmission 70 according to the temperature inside the automatic transmission 70.

  In this configuration, when the temperature inside the automatic transmission 70 is high, the second discharge passage 34 communicates with the inside of the automatic transmission 70. For this reason, when the temperature inside the automatic transmission 70 is high, it is possible to prevent seizure from occurring inside the automatic transmission 70 by guiding the hydraulic oil to the inside of the automatic transmission 70. When the temperature inside the transmission 70 is low and the need to cool or lubricate the inside of the automatic transmission 70 is low, the hydraulic oil is guided to the suction side of the first oil pump 10 and the second oil pump 20 in preference. Thus, it is possible to suppress the occurrence of cavitation and erosion in the suction portions of the first oil pump 10 and the second oil pump 20.

  Although the embodiments of the present invention have been described above, each of the above embodiments only shows a part of application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiments. is not.

  The working fluid supply devices 100 and 200 according to the above embodiments use working oil as the working fluid, but may use an incompressible fluid such as water or an aqueous solution instead of the working oil.

  Further, the working fluid supply devices 100 and 200 according to the above embodiments have been described as supplying the working fluid to the power transmission device of the vehicle, but this is not limited to the vehicle and is supplied from a pump. Any device may be used as long as it has a power transmission device that is operated by a working fluid.

  DESCRIPTION OF SYMBOLS 100,200 ... Working fluid supply apparatus, 10 ... 1st oil pump, 20 ... 2nd oil pump, 30, 130 ... discharge | emission part, 32 ... discharge passage, 33 ... 1st 1 discharge passage (release passage), 33a... First suction side passage (release passage), 33b... Second suction side passage (release passage), 34. ... Unload valve (release valve), 35a ... First unload valve (release valve, switching valve), 35b ... Second unload valve (release valve, switching valve), 35c ... Un Load control valve (release valve, switching valve), 36 ... first on-off valve (switching valve), 37 ... second on-off valve (switching valve), 38 ... third on-off valve (switching valve), 40 ... Controller (switching control unit), 50 ... Engine (first drive source), 60 ... Electric motor (second drive) Source), 70 ... automatic transmission (power transmission device), 138 ... temperature sensitive on-off valve

Claims (8)

A working fluid supply device that controls supply of a working fluid to a power transmission device that transmits an output of a first drive source to drive wheels of a vehicle,
A first pump driven by the output of the first drive source and capable of supplying a working fluid to the power transmission device;
A second pump driven by an output of a second drive source and capable of supplying a working fluid to the power transmission device;
A discharge part capable of discharging the working fluid discharged from the first pump to at least one of the suction side of the first pump, the suction side of the second pump, and the inside of the power transmission device; With
The discharge part is
A discharge passage communicating with at least one of the suction side of the first pump, the suction side of the second pump, and the inside of the power transmission device;
A working fluid supply device comprising: a discharge valve that opens the valve to release the working fluid discharged from the first pump into the discharge passage.   The working fluid supply device according to claim 1, wherein the discharge unit further includes a switching valve that switches a communication destination of the discharge passage according to an operating state of the second pump or the power transmission device. A switching control unit for switching and controlling the switching valve;
When it is determined that the discharge flow rate of the second pump exceeds a predetermined flow rate, the switching control unit causes the discharge passage to communicate with at least the suction side of the second pump. The working fluid supply device according to claim 2, wherein the switching valve is controlled. A switching control unit for switching and controlling the switching valve;
When the temperature inside the power transmission device is expected to rise, the switching control unit controls the switching valve so that the discharge passage communicates with at least the inside of the power transmission device. The working fluid supply apparatus according to claim 2.   The working fluid supply apparatus according to claim 1, wherein the discharge passage always communicates with the suction side of the first pump.   The working fluid supply device according to claim 1, wherein the discharge passage always communicates with the suction side of the second pump.   The working fluid supply device according to claim 1, wherein the discharge passage always communicates with the inside of the power transmission device.   The working fluid supply according to claim 1, wherein the discharge passage communicates with the inside of the power transmission device according to a temperature inside the power transmission device. apparatus.

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