JP7037759B2 - Engine oil viscosity detector - Google Patents

Description

The present invention relates to an engine oil viscosity detector.

An oil pump driven by the engine is provided for lubrication and cooling of various parts of the engine. The oil pump is generally a variable displacement type so as to supply an appropriate hydraulic pressure according to the operating condition of the engine.

On the other hand, since the viscosity of the oil used in the engine has a great influence on the performance such as lubrication, the viscosity of the oil used is also detected. Patent Document 1 discloses that the viscosity of oil is detected based on the integrated time until the rotation speed of the oil pump reaches the set rotation speed.

Detecting the viscosity of oil is also important in terms of reliably starting the engine, for example, when it is extremely cold. For example, if the engine is started in the extremely cold state while oil for warm weather (for example, 10W-30) is used, the viscosity of the oil may be too high to start the engine. do not have. In particular, from the viewpoint that the engine can be started smoothly and quietly when the engine is automatically restarted from the engine stopped state due to idle stop, the engine is started by ISG (a device that combines a starter motor and a generator). Driving) is also becoming more common. However, since the drive torque of the ISG in the low speed range is small, if the viscosity of the oil is too high, the engine cannot be started easily.

Japanese Unexamined Patent Publication No. 2008-267866

By the way, the viscosity of the oil is detected based on the oil pressure of the oil discharged from the oil pump. That is, under the same conditions, the higher the viscosity of the oil, the higher the hydraulic pressure.

In the above-mentioned variable capacity oil pump, the discharge amount of oil can be changed according to the amount of oil supplied to the pressure chamber. Then, the amount of oil supplied to the pressure chamber is adjusted by, for example, a linear solenoid type adjusting valve (pressure adjusting valve). Then, the amount of oil supplied to the pressure chamber is adjusted so that the actual oil pressure after being discharged from the oil pump becomes the target oil pressure determined by the operating state of the engine (for example, the engine speed and the engine load). Feedback control is also performed.

The control valve has variations. That is, even if the driving state of the adjusting valve (for example, the driving duty ratio) is the same, the amount of oil supplied to the pressure chamber of the oil pump will vary. Therefore, even if the driving state of the regulating valve is set to a predetermined constant state and the viscosity of the oil is detected according to the hydraulic pressure at this time, the viscosity of the oil can be detected accurately due to the error due to the variation of the regulating valve. Becomes impossible. The variation in the regulating valve increases as the amount of oil supplied from the regulating valve to the pressure chamber increases.

The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide an engine oil viscosity detecting device capable of accurately detecting oil viscosity based on hydraulic pressure.

In order to achieve the above object, the following solution method is adopted in the present invention. That is, as described in claim 1,
A variable capacity oil pump having a pressure chamber and set so that the amount of oil discharged increases as the amount of oil supplied to the pressure chamber decreases.
A pressure regulating valve that adjusts the amount of oil supplied to the pressure chamber,
A hydraulic control means for controlling the pressure adjusting valve according to the operating state of the engine, and
Viscosity detecting means that detects the viscosity of oil based on hydraulic pressure,
Equipped with
When the viscosity detecting means detects the viscosity of the oil, the oil pressure control means increases the oil pressure by reducing the amount of oil supplied to the pressure chamber from a predetermined amount set according to the operating state of the engine. At the same time, the pressure adjusting valve is controlled so as not to exceed the upper limit hydraulic pressure set according to the oil temperature.
It is done like this.

According to the above solution method, the pressure regulating valve has more variation as the amount of oil supplied to the pressure chamber is larger. Therefore, when detecting the viscosity of oil, by controlling the pressure adjusting valve in a direction that reduces the variation of the pressure adjusting valve, it is possible to accurately detect the viscosity of oil based on hydraulic pressure.

Further, by reducing the amount of oil supplied from the pressure regulating valve to the pressure chamber, the amount of oil discharged from the oil pump is increased and the hydraulic pressure is increased. Then, when the hydraulic pressure exceeds the upper limit hydraulic pressure, an abnormal noise is generated from the engine (engine block), and this upper limit hydraulic pressure changes according to the temperature of the oil. Therefore, when reducing the amount of oil supplied from the pressure regulating valve to detect the viscosity of the oil, the pressure regulating valve is controlled so as not to exceed the upper limit hydraulic pressure set according to the oil temperature, so that the engine can be used. The generation of abnormal noise is prevented. Of course, even when the amount of oil supplied from the pressure control valve to the pressure chamber is reduced to detect the viscosity of the oil, sufficient oil is discharged from the oil pump, so there is no need to run out of oil or run out of oil. The viscosity of the oil can be detected.

A preferred embodiment premised on the above-mentioned solution method is as described in claim 2 and below. That is,
When the viscosity of the oil is detected by the viscosity detecting means, the oil pressure control means reduces the amount of oil supplied to the pressure chamber to increase the oil pressure as compared with the case where the oil temperature is low and high. The pressure regulating valve is controlled so as to (corresponding to claim 2). In this case, the lower the oil temperature, the higher the upper limit hydraulic pressure. Therefore, the upper limit hydraulic pressure is set as high as possible according to the oil temperature to prevent the generation of abnormal engine noise and the oil from the pressure control valve to the pressure chamber. It is preferable to reduce the supply amount more sufficiently and to detect the viscosity of the oil more accurately.

When the oil pressure control means detects the viscosity of oil by the viscosity detecting means, the time for reducing the amount of oil supplied to the pressure chamber is lengthened as compared with the case where the oil temperature is low and high. The pressure regulating valve is controlled so that the time during which the oil pressure is high is increased (corresponding to claim 3). In this case, the lower the oil temperature, the higher the upper limit oil pressure. Therefore, when the oil temperature is low, the time during which the amount of oil supplied from the pressure control valve to the pressure chamber is reduced (the oil pressure is lower) than when the oil temperature is high. It is preferable to set a long time) to detect the viscosity of the oil more accurately while preventing the generation of abnormal noise of the engine.

The viscosity detecting means detects the viscosity of oil on condition that the engine speed is lower than a predetermined speed at a low speed (corresponding to claim 4). In this case, when the engine speed is low, a large difference in hydraulic pressure due to the difference in oil viscosity appears, which is preferable for accurately detecting the oil viscosity.

The viscosity detecting means detects the viscosity of oil on condition that it is in idle operation (corresponding to claim 5). In this case, it is preferable to fully exert the effect corresponding to claim 4. Further, since the oil viscosity is detected according to the hydraulic pressure in the state where the engine rotation is stable during idle operation, it is extremely preferable for accurately detecting the oil viscosity.

Before the viscosity detecting means detects the viscosity of the oil, the hydraulic pressure controlling means feedback-controls the pressure adjusting valve so that the target hydraulic pressure becomes the target hydraulic pressure according to the operating state of the engine in advance, and sets the actual hydraulic pressure to the target hydraulic pressure. After converging to, the pressure regulating valve is controlled so that the amount of oil supplied to the pressure chamber is reduced from a predetermined amount set according to the operating state of the engine (claimed). Corresponding to item 6). In this case, since the oil viscosity is detected according to the hydraulic pressure after the hydraulic pressure is stabilized in advance, it is extremely preferable for accurately detecting the oil viscosity.

When it is detected that the viscosity of the oil used by the viscosity detecting means is higher than the reference viscosity, the notification means for notifying that the start of the engine cannot be guaranteed is provided. (Corresponding to claim 7). In this case, it is preferable to prevent a situation in which the engine cannot actually be started. It is also preferable for encouraging an early change to an oil having a recommended viscosity.

A starter motor that drives the engine when the ignition switch is turned on,
ISG that drives the engine when the engine is automatically restarted from idle stop,
A start control means for selectively switching the drive between the starter motor and the ISG,
Further prepare
The start control means is at the time of automatic restart of the engine from the idle stop when it is detected that the viscosity of the oil used by the viscosity detection means is higher than the reference viscosity. Also causes the engine to be started by the starter motor.
(Corresponding to claim 8). In this case, when the engine is automatically restarted from the idle stop, the engine can be started smoothly and with low noise by starting the engine by ISG. In addition, when the oil has a high viscosity and causes a problem in the startability of the engine, the engine can be started reliably by starting the engine with the starter motor even when the engine is automatically restarted from the idle stop. be able to.

According to the present invention, oil viscosity can be detected with high accuracy based on hydraulic pressure. In addition, when the viscosity of the oil is detected, the generation of abnormal noise from the engine is prevented.

The figure which shows the example of the control system of this invention. Sectional drawing which shows an example of the variable capacity type oil pump. The figure which shows the difference of the detected hydraulic pressure by the difference of viscosity. A time chart showing a control example of the present invention. The figure which shows the relationship between oil temperature, oil pressure and engine vibration. A flowchart showing a method for estimating the viscosity of oil. The flowchart which shows the example of the proper use of the drive means for starting an engine. The flowchart which shows the modification of FIG.

In FIG. 1, reference numeral 1 denotes an engine, and the driving force of the engine 1 is transmitted to drive wheels (not shown) via a transmission 2 (automatic transmission in the embodiment) and an output shaft 3.

The engine 1 is equipped with a starter motor 4, an ISG5, and an oil pump 6 as auxiliary equipment. The starter motor 4 is always cut off from the crank shaft of the engine 1, and when the ignition switch is turned on, the starter motor 4 is coupled to the crank shaft to drive the engine 1. On the other hand, the starter motor 4 has an advantage that the drive torque when starting the engine 1 is large. At the time of its operation, it is inferior in terms of noise and smoothness of driving because it is coupled and disconnected from the crank shaft.

The ISG5 is always interlocked with the crank shaft via a gear, a belt, a chain, or the like. The ISG 5 is operated when the engine 1 is automatically restarted from an idle stop (functions as a starter motor). It also functions as a generator when the vehicle decelerates (energy recovery by regeneration). Although the ISG5 has a small drive torque in a low rotation range, it has the advantages of low noise when functioning as a starter motor and smooth operation.

The oil pump 6 has a variable capacity and is driven by the engine 1 (crank shaft). Hereinafter, the oil pump 6 will be described with reference to FIG. 2.

First, the oil pump 6 has a housing 61, a drive shaft 62, a pump element, a cam ring 66, a spring 67, and a ring member 68. Since the housing 61 is fixed to (the cylinder block of) the engine 1, it may cause an abnormal noise to be generated in the engine 1 depending on the operating state of the oil pump 6.

The housing 61 is composed of a pump body having a pump accommodating chamber formed so as to open one end side and having a space having a circular cross section inside, and a cover member for closing the opening on the one end side of the pump body. .. The drive shaft 62 is rotatably supported by the housing 61, penetrates substantially the center of the pump accommodation chamber, and is rotationally driven by the crank shaft. The pump element is rotatably housed in the pump housing chamber and can freely appear and disappear in the rotor 63 whose central portion is coupled to the drive shaft 62 and in a plurality of slits formed by radially notching the outer peripheral portion of the rotor 63. Consists of contained vanes 64. The cam ring 66 is eccentrically arranged on the outer peripheral side of the pump element with respect to the rotation center of the rotor 63, and together with the rotor 63 and the vanes 64 adjacent to each other, defines a plurality of hydraulic oil chambers, the pump chamber 65.

The spring 67 is an urging member housed in the pump body and constantly urges the cam ring 66 toward the side where the amount of eccentricity of the cam ring 66 with respect to the rotation center of the rotor 63 increases. The ring members 68 are slidably arranged on both side portions on the inner peripheral side of the rotor 63, and are a pair of ring-shaped members having a diameter smaller than that of the rotor 63.

Further, the housing 61 has a suction port 61a for supplying oil to the internal pump chamber 65 and a discharge port 61b for discharging oil from the pump chamber 65. Inside the housing 61, a pressure chamber 69 defined by the inner peripheral surface of the housing 61 and the outer peripheral surface of the cam ring 66 is formed.

As described above, in the oil pump 6, by introducing oil into the pressure chamber 69, the cam ring 66 swings with respect to the fulcrum 61c, and the rotor 63 is eccentric with respect to the cam ring 66. The discharge capacity of No. 6 is configured to change.

The suction port 61a of the oil pump 6 is connected to an oil pan (not shown) via a suction side oil passage 80. The discharge port 61b of the oil pump 6 is connected to the discharge side oil passage 81.

The oil pumped up by the oil pump 6 passes through the discharge side oil passage 81, is filtered by an oil filter (not shown), is cooled by an oil cooler, and then is introduced into the main gallery or the like in the cylinder block of the engine 1. Will be done.

The amount of oil supplied to the pressure chamber 69 is adjusted by a pressure regulating valve 7 including a linear solenoid valve. The oil passage 81a to which the pressure adjusting valve 7 is connected is branched from the discharge side oil passage 81.

Again, in FIG. 1, in the figure, U is a controller (control unit) configured by using a microcomputer. Signals from various sensors S1 to S4 are input to the controller U. The sensor S1 is a rotation speed sensor that detects the engine rotation speed. The sensor S2 is an engine load sensor that detects an engine load (for example, an accelerator opening degree or a fuel injection amount). The sensor S3 is a hydraulic pressure sensor that detects the hydraulic pressure of the discharge side oil passage 81 in which oil is discharged from the oil pump 6. The sensor S4 is an oil temperature sensor that detects the oil temperature (oil temperature). The oil pressure sensor S3 detects the oil pressure at an appropriate portion (for example, an inlet portion or an outlet portion of the main gallery of the engine 1) in the discharge side oil passage 81. The oil temperature sensor S4 can also be arranged at substantially the same position as the hydraulic pressure sensor S3.

Next, the relationship between the viscosity of the oil, the hydraulic pressure, and the engine speed will be described with reference to FIG. First, as oils having different viscosities, 0W-20 oil having a relatively high viscosity and 0W-16 oil having a lower viscosity were used. The actual oil pressure for both oils and the oil pressure difference between the two oils are collectively shown in FIG. 3 while changing the engine speed with the discharge amount of the oil pump 6 increased.

As can be understood from FIG. 3, the difference in oil pressure based on the difference in oil viscosity becomes more remarkable as the engine speed is lower. That is, it is preferable to detect the oil pressure in a state where the engine speed is low in order to accurately detect the viscosity of the oil based on the oil pressure.

The controller U stores a reference hydraulic pressure using a suitable oil as a reference oil when it is extremely cold. That is, using the reference oil, the discharge amount of the oil pump 6 is set to a predetermined discharge amount (a range that does not exceed the upper limit hydraulic pressure described later when the predetermined discharge amount is reached) in which the discharge amount of the oil pump 6 is increased from the discharge amount according to the operating state of the engine. Moreover, the actual hydraulic pressure obtained when the engine 1 is operated at a low rotation speed (for example, idle rotation speed) is stored as a reference hydraulic pressure. Then, by comparing the actual hydraulic pressure under the same conditions as above with the reference hydraulic pressure, it can be determined whether the oil actually used has a higher viscosity (or a lower viscosity) than the reference oil. It is possible to make a judgment including the difference. It is preferable to set (store) the reference hydraulic pressure with the oil temperature (or the oil temperature and the engine speed) as parameters in order to increase the chance of detecting the oil viscosity.

FIG. 4 is a time chart showing a method of detecting oil viscosity by the controller U. In FIG. 4, as the actual hydraulic pressure, the actual hydraulic pressure (solid line) in the oil of 0W-20 as the reference oil and the actual hydraulic pressure (broken line) in the comparative oil of 5W-30 having a higher viscosity than that are shown. Further, the "oil pump drive DUTY" is actually the drive duty ratio of the pressure regulating valve 7 (the smaller the drive duty ratio, the smaller the amount of oil supplied to the pressure chamber 69, and the oil from the oil pump 6 is used. The discharge amount is increased, and the hydraulic pressure is increased accordingly).

Before the time point t1, the engine 1 is started, and at the time point t1, the idle speed becomes stable. At the stage before the time point t1, the actual oil pressure becomes larger when the comparative oil is used than when the reference oil is used.

The pressure adjusting valve 7 is feedback-controlled so that the hydraulic pressure becomes the target hydraulic pressure between the time points of t1 and t2 when the idle rotation speed is reached. As a result, the actual oil pressure is the same regardless of whether the reference oil or the comparative oil is used.

At a stage slightly before the time point t2, the hydraulic pressure becomes stable by the hydraulic feedback control. With this hydraulic pressure stable, the drive duty ratio to the pressure control valve 7 is reduced until the time t3, and the amount of oil supplied to the pressure chamber 69 of the oil pump 6 is reduced (from the oil pump 6). The oil discharge rate is increased and the oil pressure is increased). In this state, the oil pressure detected by the oil pressure sensor S3 is compared with the reference oil pressure, and the viscosity of the oil actually used is detected. When detecting the viscosity of the oil, the actual oil pressure is prevented from exceeding the upper limit oil pressure set according to the oil temperature detected by the oil temperature sensor S4. The upper limit hydraulic pressure will be described later.

The oil viscosity detection is completed by the time t3, and the hydraulic feedback control is restarted after the time t3.

Next, the above-mentioned upper limit hydraulic pressure will be described with reference to FIG. In FIG. 5, the oil temperature and the oil pressure are set as parameters. In the figure, the region below the β ray (the region where the hydraulic pressure is small) is defined as the region where the engine 1 does not generate an abnormal noise. In the figure, the α-ray is set as a hydraulic pressure higher than the β-ray, and in the region where the hydraulic pressure is higher than the α-ray, the engine 1 is regarded as a region where abnormal noise is generated, and is substantially unusable. The region between the α-rays and the β-rays is a region that can be used without causing an abnormal noise in the engine 1 for a predetermined time (for example, about 0.5 seconds to 2 seconds).

At the time of detecting the viscosity of the oil, the amount of oil supplied from the pressure regulating valve 7 to the pressure chamber 69 is reduced, and the amount of oil discharged from the oil pump 6 is increased accordingly, so that the oil pressure is increased. Then, as long as the magnitude of the hydraulic pressure increased at this time does not exceed the β ray of FIG. 5, the engine 1 does not generate an abnormal noise. Then, in the embodiment, the hydraulic pressure along the β ray is the upper limit hydraulic pressure. Of course, since the upper limit hydraulic pressure (β ray) is changed according to the oil temperature (oil temperature), the upper limit hydraulic pressure is set according to the oil temperature.

By limiting the oil viscosity detection time to the above-mentioned predetermined time, it is possible to set the upper limit hydraulic pressure as a hydraulic pressure having a large range between α rays and β rays. In this case, when the oil temperature is low, the predetermined time can be lengthened as compared with when the oil temperature is high.

Next, the content of control by the controller U will be described with reference to the flowcharts shown in FIG. 6 and below.

First, FIG. 6 is a process for detecting the viscosity of the oil actually used. First, after signals from various sensors S1 to S3 are input in Q1, the target hydraulic pressure is set according to the operating state of the engine 1 in Q2 (for example, the target hydraulic pressure is set with the engine rotation speed and the engine load as parameters). Decision).

In Q3, it is determined whether or not it is in idle operation. If NO in the determination of Q3, the pressure adjusting valve 7 is feedback-controlled in Q4 so that the actual hydraulic pressure detected by the sensor S3 becomes the target hydraulic pressure.

If YES in the determination of Q3, it is determined in Q5 whether or not the viscosity estimation completion flag is 0. This viscosity estimation completion flag indicates that the viscosity estimation is not completed when it is 0. The viscosity estimation completion flag is reset to 0, for example, when the ignition switch is turned off and the engine 1 is stopped. When the determination of Q5 is NO (when the viscosity estimation is completed), the process is changed to Q4.

If YES in the determination of Q5, the viscosity estimation has not been completed, so the viscosity estimation is newly performed. That is, in Q6, the pressure adjusting valve 7 is feedback-controlled so that the actual hydraulic pressure becomes the target hydraulic pressure (corresponding to the control between t1 and t2 in FIG. 4). After that, in Q7, it is determined whether or not the actual hydraulic pressure has converged to the target hydraulic pressure. If the determination of Q7 is NO, the process returns to Q6.

If YES in the determination of Q7, in Q8, the drive duty ratio of the CCV, that is, the pressure regulating valve 7 is reduced, the amount of oil discharged from the oil pump 6 is increased, and the oil pressure is increased. At this time, the pressure regulating valve 7 is controlled to have the above-mentioned upper limit hydraulic pressure set according to the oil temperature (for example, feedback control). After that, in Q9, the viscosity of the oil currently used is detected (estimated) by comparing the actual oil pressure with the reference oil pressure, and the detection result is stored. After that, in Q10, the viscosity estimation completion flag is set to 1 to indicate that the viscosity estimation is completed.

FIG. 7 shows a control example in which the engine is started according to the viscosity of the oil estimated by the process of FIG. The processing of FIG. 7 is performed by parallel processing or interrupt processing with respect to the processing of FIG.

First, after the data is input in Q21, it is determined in Q22 whether or not the engine 1 is started by turning on the ignition switch. If YES in the determination of Q21, in Q23, whether or not the viscosity of the oil estimated by the process of FIG. 6 has a high viscosity (whether or not the viscosity is higher than a predetermined value than the viscosity of the reference oil) is determined. It is determined.

If YES in the determination of Q23, the engine is started by driving the starter motor 4 in order to surely start the engine 1 in Q24. If the determination in Q23 is NO, the engine is started by making the ISG5 function as a starter motor (starting smoothly and with low noise).

If NO in the determination of Q22, it is determined in Q26 whether or not the engine is automatically restarted from the time when the engine is stopped due to idle stop. If YES in the determination of Q26, it is determined in Q27 whether or not the stored content in Q9 of FIG. 6 is a highly viscous oil. If YES in the determination of Q27, the engine 1 is started by operating the starter motor 4 in Q28.

If NO in the determination of Q27, the engine 1 is started by operating the ISG 5 (functioning as a starter motor) in Q29. After Q29, in Q30, it is determined whether or not the start of the engine 1 using the ISG 5 has failed. If the determination of Q30 is YES, the process is changed to Q28. Further, when the determination of Q30 is NO, it means that the engine 1 has been started, so the engine 1 is returned as it is.

If NO in the determination of Q26, the starter motor 4 and the IEG 5 are each set to the drive stop state in Q31.

As described above, in the above embodiment, the automatic engine restart from the idle stop is basically an engine start by ISG5 in order to perform it smoothly and with low noise. However, when high-viscosity oil is used, the starter motor 4 is also used as appropriate to start the engine.

FIG. 8 shows a second embodiment of the present invention, which is a modification of FIG. 7. In the present embodiment, the starter motor 4 is not provided, and the engine 1 is always started by the ISG5.

In the present embodiment, after the data is input in Q41, it is determined in Q42 whether or not the engine 1 is started (whether or not it is started by the ignition switch or automatically restarted from the idle stop). ). If the determination of Q42 is NO, the ISG5 is stopped in Q43 (the function as a starter motor is stopped and the function as a generator is appropriately executed).

If YES in the determination of Q42, it is determined in Q4 whether or not the content estimated and stored in Q9 of FIG. 6 is a highly viscous oil. If YES in the determination of Q44, it is notified that the start of the engine 1 cannot be guaranteed because the oil is not recommended (character display on the display screen and / or voice notification from the speaker). After that, in Q46, the ISG 5 is driven to start the engine 1. If the determination of Q44 is NO, the process shifts to Q46 without going through Q45.

Although the embodiments have been described above, the present invention is not limited to the embodiments, and appropriate modifications can be made within the scope of the claims. When detecting the viscosity of oil, when the oil temperature is low, the time for reducing the amount of oil supplied to the pressure chamber 69 is lengthened, and the time for increasing the oil pressure is longer than when the oil temperature is high. The pressure adjusting valve 7 may be controlled as such (the oil detection time may be sufficiently secured as much as possible). The engine 1 may be started only by the starter motor 4. The detected (estimated) oil viscosity was used for starting control of the engine 1, but it can also be used for any other purpose (for example, correction of the target hydraulic pressure, shift timing of the automatic transmission 2). Correction etc.). The oil viscosity detection can be performed not only during idle operation but also when the engine speed is lower than a preset predetermined speed (for example, 1500 rpm). Of course, the object of the present invention is not limited to what is specified, but also implicitly includes providing what is expressed as substantially preferable or advantageous.

The present invention is suitable for detecting the viscosity of oil.

1: Engine 4: Starter motor 5: ISG
6: Oil pump 7: Pressure control valve 69: Pressure chamber 81: Discharge side oil passage 81a: Branch oil passage U: Controller S1: Engine rotation speed sensor S2: Engine load sensor S3: Hydraulic sensor S4: Oil temperature sensor

Claims (8)

A variable capacity oil pump having a pressure chamber and set so that the amount of oil discharged increases as the amount of oil supplied to the pressure chamber decreases.
A pressure regulating valve that adjusts the amount of oil supplied to the pressure chamber,
A hydraulic control means for controlling the pressure adjusting valve according to the operating state of the engine, and
Viscosity detecting means that detects the viscosity of oil based on hydraulic pressure,
Equipped with
When the viscosity detecting means detects the viscosity of the oil, the oil pressure control means increases the oil pressure by reducing the amount of oil supplied to the pressure chamber from a predetermined amount set according to the operating state of the engine. At the same time, the pressure adjusting valve is controlled so as not to exceed the upper limit hydraulic pressure set according to the oil temperature.
An engine oil viscosity detector characterized by this. In claim 1,
When the viscosity of the oil is detected by the viscosity detecting means, the oil pressure control means reduces the amount of oil supplied to the pressure chamber to increase the oil pressure as compared with the case where the oil temperature is low and high. An oil viscosity detecting device for an engine, characterized in that the pressure regulating valve is controlled as described above. In claim 1,
When the viscosity of the oil is detected by the viscosity detecting means, the hydraulic pressure control means increases the time for reducing the amount of oil supplied to the pressure chamber longer than when the oil temperature is low and high. An engine oil viscosity detection device, characterized in that the pressure regulating valve is controlled so that the time during which the oil pressure is high is extended. In any one of claims 1 to 3,
The viscosity detecting means is an engine oil viscosity detecting device, which detects the viscosity of oil on condition that the engine rotation speed is lower than a predetermined rotation speed. In claim 4,
The viscosity detecting means is an engine oil viscosity detecting device, which detects the viscosity of oil on condition that it is in idle operation. In any one of claims 1 to 5,
Before the viscosity detecting means detects the viscosity of the oil, the hydraulic pressure controlling means feedback-controls the pressure adjusting valve so that the target hydraulic pressure becomes the target hydraulic pressure according to the operating state of the engine in advance, and sets the actual hydraulic pressure to the target hydraulic pressure. The engine is characterized in that the pressure adjusting valve is controlled so that the amount of oil supplied to the pressure chamber is reduced from a predetermined amount set according to the operating state of the engine after the oil pressure is converged to. Oil viscosity detector. In any one of claims 1 to 6,
When it is detected that the viscosity of the oil used by the viscosity detecting means is higher than the reference viscosity, the notification means for notifying that the start of the engine cannot be guaranteed is provided. An engine oil viscosity detector characterized by. In any one of claims 1 to 7,
A starter motor that drives the engine when the ignition switch is turned on,
ISG that drives the engine when the engine is automatically restarted from idle stop,
A start control means for selectively switching the drive between the starter motor and the ISG,
Further prepare
The start control means is at the time of automatic restart of the engine from the idle stop when it is detected that the viscosity of the oil used by the viscosity detection means is higher than the reference viscosity. Also causes the engine to be started by the starter motor.
An engine oil viscosity detector characterized by this.

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