JP7297391B2 - Automatic transmission oil change indicator - Google Patents

Description

The present invention relates to an oil change display device for an automatic transmission mounted on a vehicle.

Conventionally, the vehicle speed and oil temperature in the transmission are measured, an oil level map is retrieved according to the measured vehicle speed and oil temperature, and an oil deterioration determination threshold value is set. Next, the current oil deterioration level is detected, and the current oil deterioration level is compared with the above-mentioned oil determination threshold value to determine the deterioration of the oil. There is known an oil deterioration detection device that, when deterioration of the oil is detected, displays a prompt to replace the oil (see Patent Document 1).

JP 2009-138852 A

In the above-described conventional device, when deterioration of the transmission oil is detected, a display prompting for oil replacement is displayed. However, simply displaying a replacement warning when oil deterioration is detected does not convey the urgency of the user to change the transmission oil. , oil deterioration may progress. Also, if a warning is issued at an early stage in order to prevent this, there is a problem that the user may misunderstand that the frequency of oil changes is high.

The present invention has been made with a focus on the above problems, and when the deterioration of the transmission oil progresses, it is possible to change the oil without overlooking the oil change timing or increasing the oil change frequency, and without causing discomfort to the user. The purpose is to present information.

In order to achieve the above objects, the present invention provides a vehicle-mounted automatic transmission including a transmission control unit that performs hydraulic system control using transmission oil stored in an oil pan,
The transmission control unit has an oil deterioration estimation controller that calculates an oil deterioration degree estimation value of the transmission oil based on oil temperature and time.
An oil change display controller is provided for inputting the oil deterioration degree estimated value from the oil deterioration estimation controller and displaying the oil change information.
The oil change display controller sets, as the oil deterioration determination threshold, an oil change display start threshold based on the degree of oil deterioration before reaching the oil change necessary threshold.
When the estimated oil deterioration level reaches the oil change display start threshold value, the display of the travelable distance that can be traveled until the oil change necessary threshold value is reached is started.
After the display of the possible travel distance is started, the possible travel distance that decreases according to the actual travel distance after the start of display is displayed regardless of the estimated oil deterioration level.
The oil deterioration estimating controller sums the oil deterioration degree estimation value by summing the oil temperature heat deterioration progress value based on the oil temperature of the transmission oil and the clutch portion heat deterioration progress value based on the estimated temperature of the shift clutch portion of the automatic transmission. The accumulated heat deterioration progression value is defined as

In this way, after the display of the possible mileage is started, the mileage that decreases in accordance with the actual mileage after the start of display is displayed as the remaining oil change distance, regardless of the estimated oil deterioration level. It will be. As a result, when the deterioration of the transmission oil progresses, it is possible to present oil change information that does not give the user a sense of discomfort while preventing the oil change timing from being overlooked and the oil change frequency from increasing. In addition, when calculating the cumulative heat deterioration progress value, two different causes of thermal degradation of the transmission oil are reflected, so that the cumulative heat deterioration progress value can be calculated with high accuracy while suppressing variations depending on the user type.

1 is an overall system diagram showing an engine vehicle equipped with an automatic transmission to which the oil change display device of Embodiment 1 is applied; FIG. 1 is a skeleton diagram showing an example of an automatic transmission; FIG. FIG. 2 is an engagement chart showing engagement states of frictional engagement elements for shifting in an automatic transmission at respective gear stages; FIG. 2 is a shift map diagram showing an example of a shift map in an automatic transmission; FIG. 2 is a diagram showing the detailed configuration of a control valve unit of the automatic transmission; FIG. 3 is a control block diagram showing the configuration of an oil change display control system of the automatic transmission; FIG. 4 is a flow chart showing the flow of oil deterioration estimation determination processing executed by an oil deterioration estimation controller of a transmission control unit; FIG. 4 is a relationship characteristic diagram showing the relationship between the heat count coefficient and the oil temperature; FIG. 4 is a relationship characteristic diagram showing the relationship between a heat count value and a base number (BN), which is an index of oil deterioration. FIG. 4 is a relationship characteristic diagram showing the relationship between the possible travel distance, the oil change display start threshold, and the oil change necessary threshold; 4 is a flow chart showing the flow of oil change display processing executed by an oil change display controller connected to an oil deterioration estimation controller; FIG. 10 is a characteristic diagram showing the range of variation depending on the type of user when determining oil deterioration based on travel distance; FIG. 10 is a characteristic diagram showing the range of variation depending on the type of user when determining oil deterioration based on the deterioration count value; FIG. 4 is a time chart showing each characteristic when displaying the travelable distance until the oil is changed due to progress of oil deterioration in the automatic transmission; FIG.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the oil-change display apparatus of the automatic transmission of this invention is demonstrated based on Example 1 shown in drawing.

The oil change display device according to the first embodiment is applied to an engine vehicle (an example of a vehicle) equipped with an automatic transmission having nine forward gears and one reverse gear. Hereinafter, the configuration of the first embodiment will be described as "overall system configuration", "detailed configuration of automatic transmission", "detailed configuration of hydraulic control system", "detailed configuration of oil change display control system", and "oil deterioration estimation processing configuration". ” and “oil change display processing configuration”.

[Overall system configuration]
FIG. 1 is an overall system diagram showing an engine vehicle equipped with an automatic transmission to which the oil change display device of Embodiment 1 is applied. The overall system configuration will be described below with reference to FIG.

The drive system of the engine vehicle includes an engine 1, a torque converter 2, an automatic transmission 3, a propeller shaft 4, and driving wheels 5, as shown in FIG. The torque converter 2 incorporates a lockup clutch 2a that directly connects the crankshaft of the engine 1 and the input shaft IN of the automatic transmission 3 by engagement. Attached to the automatic transmission 3 is a control valve unit 6 comprising a spool valve, a hydraulic control circuit, a hydraulic solenoid valve (hereinafter referred to as "hydraulic solenoid"), etc., and having an oil pan 6a. .

The control valve unit 6 has, as hydraulic solenoids, six clutch solenoids 20 provided for each friction engagement element, and one line pressure solenoid 21, lubrication solenoid 22, and lockup solenoid 23 provided one each. That is, it has a total of 9 hydraulic solenoids. Each of these hydraulic solenoids has a three-way linear solenoid structure and operates upon receiving a control command from the transmission control unit 10 .

As shown in FIG. 1, the electronic control system of the engine vehicle includes a transmission control unit 10 (abbreviated as "ATCU"), an engine control unit 11 (abbreviated as "ECU"), and a CAN communication line. 12 and.

Here, the transmission control unit 10 is mechanically and electrically integrated on the upper surface of the control valve unit 6 . The transmission control unit 10 is provided with a main board temperature sensor 31 and a sub board temperature sensor 32 in a redundant system as board temperature sensors for detecting the temperature of the unit board. The independence of the main substrate temperature sensor 31 and the sub substrate temperature sensor 32 is guaranteed. That is, the main board temperature sensor 31 and the sub board temperature sensor 32 send the main temperature sensor value and the sub board temperature sensor value to the transmission control unit 10. Send temperature information that is not in direct contact with the machine fluid (ATF). Transmission working fluid (ATF) is hereinafter referred to as "transmission oil", and the main temperature sensor value (or sub temperature sensor value) is used as oil temperature information in oil deterioration determination.

A transmission control unit 10 that controls the automatic transmission 3 receives signals from a turbine rotation sensor 13, an output shaft rotation sensor 14, an ignition switch 15, an inhibitor switch 18, an intermediate shaft rotation sensor 19, and the like.

Turbine rotation sensor 13 detects the turbine rotation speed of torque converter 2 (=transmission input shaft rotation speed) and sends a signal of turbine rotation speed NT to transmission control unit 10 . The output shaft rotation sensor 14 detects the output shaft rotation speed of the automatic transmission 3 and sends a signal of the output shaft rotation speed No (=vehicle speed VSP) to the transmission control unit 10 . The ignition switch 15 sends an ignition switch signal (on/off) to the transmission control unit 10 . The inhibitor switch 18 detects a range position selected by a user's selection operation on a select lever, select button, or the like, and sends a range position signal to the transmission control unit 10 . The intermediate shaft rotation sensor 19 detects the rotation speed of the intermediate shaft (intermediate shaft = rotating member connected to the first carrier C1) and sends a signal of the intermediate shaft rotation speed Nint to the transmission control unit 10 .

The transmission control unit 10 monitors changes in operating points (VSP, APO) due to vehicle speed VSP and accelerator opening APO on a gear shift map (see FIG. 4).
1. Auto upshift (due to vehicle speed increase while maintaining accelerator opening)
2. Foot release upshift (by accelerator foot release operation)
3. Foot return upshift (by accelerator return operation)
4. Power-on downshift (due to vehicle speed decrease while maintaining accelerator opening)
5. Small-opening sudden step downshift (due to small accelerator operation amount)
6. Large-opening sudden downshift (depending on the amount of accelerator operation: "Kickdown")
7. Gentle downshift (by gently depressing the accelerator and increasing vehicle speed)
8. Coast downshift (due to vehicle speed drop when accelerator foot is released)
Shift control is performed using a basic shift pattern called .

The engine control unit 11 receives signals from an accelerator opening sensor 16, an engine rotation sensor 17, and the like.

The accelerator opening sensor 16 detects the accelerator opening due to the driver's accelerator operation and sends a signal of the accelerator opening APO to the engine control unit 11 . The engine speed sensor 17 detects the speed of the engine 1 and sends a signal of the engine speed Ne to the engine control unit 11 .

In the engine control unit 11, in addition to various controls for the engine alone, engine torque limit control and the like are performed through coordinated control with control by the transmission control unit 10. FIG. The transmission control unit 10 and the engine control unit 11 are connected via a CAN communication line 12 capable of bidirectionally exchanging information. Therefore, when an information request is input from the transmission control unit 10, the engine control unit 11 transmits information on the accelerator opening APO, the engine speed Ne, the engine torque Te, and the turbine torque TT to the transmission control unit 10 in response to the request. Output to 10. Further, when an engine torque limitation request based on the upper limit torque is input from the transmission control unit 10, engine torque limitation control is executed to limit the engine torque to a predetermined upper limit torque.

[Detailed configuration of automatic transmission]
2 is a skeleton diagram showing an example of the automatic transmission 3, FIG. 3 is an engagement table for the automatic transmission 3, and FIG. 4 is an example of a shift map for the automatic transmission 3. FIG. The detailed configuration of the automatic transmission 3 will be described below with reference to FIGS. 2 to 4. FIG.

The automatic transmission 3 is characterized by the following points.
(a) A one-way clutch that engages/idles mechanically is not used as a transmission element.
(b) The first brake B1, second brake B2, third brake B3, first clutch K1, second clutch K2, and third clutch K3, which are frictional engagement elements, are engaged/engaged independently by clutch solenoids 20 during shifting. Release state is controlled.
(c) The second clutch K2 and the third clutch K3 have a centrifugal cancel chamber that cancels the centrifugal pressure due to the centrifugal force acting on the clutch piston oil chamber.

As shown in FIG. 2, the automatic transmission 3 includes, as planetary gears constituting a gear train, a first planetary gear PG1, a second planetary gear PG2, and a third planetary gear PG2 in order from the input shaft IN toward the output shaft OUT. It has a planetary gear PG3 and a fourth planetary gear PG4.

The first planetary gear PG1 is a single pinion type planetary gear, and has a first sun gear S1, a first carrier C1 that supports a pinion that meshes with the first sun gear S1, and a first ring gear R1 that meshes with the pinion.

The second planetary gear PG2 is a single pinion type planetary gear, and has a second sun gear S2, a second carrier C2 that supports a pinion that meshes with the second sun gear S2, and a second ring gear R2 that meshes with the pinion.

The third planetary gear PG3 is a single pinion type planetary gear, and has a third sun gear S3, a third carrier C3 supporting a pinion that meshes with the third sun gear S3, and a third ring gear R3 that meshes with the pinion.

The fourth planetary gear PG4 is a single pinion type planetary gear, and has a fourth sun gear S4, a fourth carrier C4 supporting a pinion that meshes with the fourth sun gear S4, and a fourth ring gear R4 that meshes with the pinion.

The automatic transmission 3, as shown in FIG. 2, includes an input shaft IN, an output shaft OUT, a first connecting member M1, a second connecting member M2, and a transmission case TC. A first brake B1, a second brake B2, a third brake B3, a first clutch K1, a second clutch K2, and a third clutch K3 are provided as frictional engagement elements that are engaged/released by shifting. ing.

The input shaft IN is a shaft to which driving force from the engine 1 is input via the torque converter 2, and is always connected to the first sun gear S1 and the fourth carrier C4. The input shaft IN is connectably connected to the first carrier C1 via the second clutch K2.

The output shaft OUT is a shaft that outputs variable drive torque to the drive wheels 5 via the propeller shaft 4 and a final gear (not shown), and is always connected to the third carrier C3. The output shaft OUT is detachably connected to the fourth ring gear R4 via the first clutch K1.

The first connecting member M1 is a member that always connects the first ring gear R1 of the first planetary gear PG1 and the second carrier C2 of the second planetary gear PG2 without interposing a frictional engagement element. The second connecting member M2 connects the second ring gear R2 of the second planetary gear PG2, the third sun gear S3 of the third planetary gear PG3, and the fourth sun gear S4 of the fourth planetary gear PG4 without intervening frictional engagement elements. It is a member that is always concatenated.

The first brake B1 is a friction engagement element capable of locking the rotation of the first carrier C1 with respect to the transmission case TC. The second brake B2 is a frictional engagement element capable of locking the rotation of the third ring gear R3 with respect to the transmission case TC. The third brake B3 is a friction engagement element capable of locking the rotation of the second sun gear S2 with respect to the transmission case TC.

The first clutch K1 is a frictional engagement element that selectively connects between the fourth ring gear R4 and the output shaft OUT. The second clutch K2 is a frictional engagement element that selectively connects between the input shaft IN and the first carrier C1. The third clutch K3 is a frictional engagement element that selectively connects between the first carrier C1 and the second connecting member M2.

FIG. 3 shows an engagement table for achieving 9 forward speeds and 1 reverse speed in the D range by simultaneously engaging three of the six frictional engagement elements in the automatic transmission 3 . Hereinafter, based on FIG. 3, a description will be given of a shift configuration that establishes each gear stage.

The first gear (1st) is achieved by simultaneously engaging the second brake B2, the third brake B3 and the third clutch K3. The second gear (2nd) is achieved by simultaneously engaging the second brake B2, the second clutch K2 and the third clutch K3. The 3rd gear (3rd) is achieved by simultaneously engaging the second brake B2, the third brake B3 and the second clutch K2. The 4th speed (4th) is achieved by simultaneously engaging the second brake B2, the third brake B3 and the first clutch K1. The fifth speed (5th) is achieved by simultaneously engaging the third brake B3, the first clutch K1 and the second clutch K2. The above 1st to 5th gears are underdrive gears with reduction gear ratios exceeding one.

The sixth speed (6th) is achieved by simultaneously engaging the first clutch K1, the second clutch K2 and the third clutch K3. This sixth gear is a direct gear with a gear ratio of 1.

The 7th speed (7th) is achieved by simultaneously engaging the third brake B3, the first clutch K1 and the third clutch K3. The eighth speed (8th) is achieved by simultaneously engaging the first brake B1, the first clutch K1 and the third clutch K3. The ninth speed (9th) is achieved by simultaneously engaging the first brake B1, the third brake B3 and the first clutch K1. The 7th to 9th speeds described above are overdrive gears with an increasing gear ratio of less than 1.

Furthermore, when up-shifting to an adjacent gear stage or down-shifting from among the first to ninth gear stages, as shown in FIG. . That is, when shifting to an adjacent gear stage, two of the three frictional engagement elements are kept engaged, while one frictional engagement element is released and one frictional engagement element is engaged. is achieved with

A reverse speed (Rev) by selecting the R range position is achieved by simultaneously engaging the first brake B1, the second brake B2 and the third brake B3. When the N range position and the P range position are selected, all of the six friction engagement elements B1, B2, B3, K1, K2 and K3 are released.

A shift map as shown in FIG. 4 is stored in the transmission control unit 10. By selecting the D range, the shift by switching the gear stages from the 1st gear stage to the 9th gear stage on the forward side is performed by: This shift map is followed. That is, when the operating point (VSP, APO) at that time crosses the upshift line indicated by the solid line in FIG. 4, an upshift request is issued. Also, when the operating point (VSP, APO) crosses the downshift line indicated by the dashed line in FIG. 4, a downshift request is issued.

[Detailed configuration of hydraulic control system]
FIG. 5 shows the detailed configuration of the control valve unit 6. As shown in FIG. The detailed configuration of the hydraulic control system will be described below with reference to FIG.

The control valve unit 6 includes a mechanical oil pump 61 and an electric oil pump 62 as hydraulic pressure sources. The mechanical oil pump 61 is driven by the engine 1 and the electric oil pump 62 is driven by the electric motor 63 .

The control valve unit 6 includes a line pressure solenoid 21, a line pressure regulating valve 64, a clutch solenoid 20, and a lockup solenoid 23 as valves provided in the hydraulic control circuit. Further, a lubrication solenoid 22 , a lubrication pressure regulating valve 65 , a boost switching valve 66 , a P-nP switching valve 67 and a cooler 68 are provided.

The line pressure regulating valve 64 regulates the pressure of the oil discharged from at least one of the mechanical oil pump 61 and the electric oil pump 62 to the line pressure PL based on the valve actuation signal pressure from the line pressure solenoid 21 .

The clutch solenoid 20 is a shift system solenoid that uses the line pressure PL as a source pressure and controls the engagement pressure and the release pressure for each of the frictional engagement elements (B1, B2, B3, K1, K2, K3). Although FIG. 5 shows one clutch solenoid 20, there are six solenoids for each friction engagement element (B1, B2, B3, K1, K2, K3). The six clutch solenoids 20 are a first brake solenoid, a second brake solenoid, a third brake solenoid, a first clutch solenoid, a second clutch solenoid and a third clutch solenoid.

The lockup solenoid 23 controls the differential pressure of the lockup clutch 2a using surplus oil when the line pressure PL is regulated by the line pressure regulating valve 64 .

The lubrication solenoid 22 produces a valve actuation signal pressure to the lubrication pressure regulating valve 65, a switching pressure to the boost switching valve 66, and a switching pressure to the P-nP switching valve 67, and controls the lubrication flow rate to be supplied to the friction engagement element. , has the function of regulating the pressure to an appropriate flow rate to suppress heat generation. The solenoid mechanically guarantees the minimum lubrication flow rate that suppresses the heat generation of the friction engagement element when not in continuous shift protection, and adjusts the amount of lubrication flow added to the minimum lubrication flow rate.

The lubrication pressure regulating valve 65 can control the flow rate of lubrication supplied via a cooler 68 to a power train (PT) including frictional engagement elements and a gear train in accordance with the valve actuation signal pressure from the lubrication solenoid 22 . Friction is reduced by optimizing the PT supply lubrication flow rate with the lubrication pressure regulating valve 65 .

The boost switching valve 66 increases the amount of oil supplied to the centrifugal cancel chambers of the second clutch K2 and the third clutch K3 by switching pressure from the lubricating solenoid 22 . This boost switching valve 66 is used to temporarily increase the amount of supplied oil when the amount of oil in the centrifugal cancel chamber is insufficient.

The P-nP switching valve 67 switches the oil passage of the line pressure supplied to the parking module according to the switching pressure from the lubrication solenoid 22 to perform parking lock.

Thus, the control valve unit 6 includes the lubrication solenoid 22, the lubrication pressure regulating valve 65, the boost switching valve 66, and the P-nP switching valve 67, and connects the D range pressure oil passage, the R range pressure oil passage, and the like. It is characterized by eliminating the manual valve for switching.

[Detailed configuration of oil change display control system]
FIG. 6 shows the configuration of the oil change display control system of the automatic transmission 3. As shown in FIG. The detailed configuration of the oil change display control system will be described below with reference to FIG.

The oil change display control system of the automatic transmission 3, as shown in FIG. .

The transmission controller 100 is included in the transmission control unit 10 that performs hydraulic system control using the transmission oil stored in the oil pan 6a. From the shift controller 100, shift information necessary for estimating the temperature of the shift clutch portion (=frictional engagement element portion) (information on the frictional engagement element that shifts from disengagement to engagement, information on the frictional engagement element that transitions from engagement to release, etc.) is received. Output to oil deterioration estimation controller 110 .

An oil deterioration estimation controller 110 is provided in the transmission control unit 10 and calculates an oil deterioration degree estimation value based on oil temperature and time. The oil deterioration estimating controller 110 receives the shift information from the shift controller 100, the main temperature sensor value from the main substrate temperature sensor 31, and the sub temperature sensor value from the sub substrate temperature sensor 32. FIG.

The oil deterioration estimation controller 110 performs the following processing for calculating an oil deterioration degree estimated value.
(a) The oil deterioration degree estimated value is an accumulation obtained by summing the oil temperature heat deterioration progression value based on the oil temperature of the transmission oil and the clutch portion heat deterioration progression value based on the estimated temperature of the shift clutch portion of the automatic transmission 3. This is the thermal deterioration progression value.
(b) The oil temperature heat deterioration progress value is set to the oil temperature heat count value Nco calculated from the time t1 when the oil temperature exceeds the first set value and the heat count coefficient k1 determined by the oil temperature. The clutch heat deterioration progress value is the clutch heat count value Ncc calculated from the time t2 at which the estimated temperature of the clutch reaches a second set value higher than the first set value and a constant k2. Then, the accumulated heat deterioration progression value is set to the deterioration count value ΣNc (oil deterioration degree estimated value) obtained by summing the oil temperature heat count value Nco and the clutch portion heat count value Ncc.

The oil change display controller 40 is a controller that receives the deterioration count value ΣNc from the oil deterioration estimation controller 110 and displays oil change information. The oil change display controller 40 receives information on the deterioration count value ΣNc from the oil deterioration estimation controller 110 via the CAN communication line 50 . In addition to the travelable distance information, a switch signal from the ignition switch 15, a switch signal from the reset switch 43, and distance information from the odometer 44 (odometer) are input.

The oil change display controller 40 performs the following oil change display processing.
(a) As an oil deterioration determination threshold, an oil change display start threshold Dth is set according to the degree of oil deterioration before reaching the oil change necessary threshold Rth.
(b) When the deterioration count value ΣNc reaches the oil change display start threshold value Dth, an initial value Me0 of the travelable distance that can be traveled before reaching the oil change necessary threshold value Rth is calculated, and the display of the travelable distance Me is started. Here, the initial value Me0 of the travelable distance that can be traveled until the oil change threshold Rth is reached is estimated and calculated on the assumption that the slope of increase of the deterioration count value ΣNc with respect to the actual traveled distance up to now continues.
(c) Store the initial value Me0 of the travelable distance at the start of display, and store the distance of the odometer 44 at the start of display.
(d) After starting to display the travelable distance Me, the travelable distance Me is displayed that decreases in accordance with the actual traveled distance after the start of display, regardless of the deterioration count value ΣNc.
(e) While the ignition is on, display the travelable distance Me on the main display 41 (display display).
(f) When the user changes the oil and starts the operation to cancel the display of the reset switch 43 while the ignition is on, the deterioration count value ΣNc is set to zero to the oil deterioration estimation controller 110 via the CAN communication line 50. start outputting the reset signal to When the display cancellation operation to the reset switch 43 is completed while the ignition is on, the display on the main display 41 and the sub-display 42 is erased, and the output of the reset signal is also terminated.

The main display 41 is a character display that is arranged in an instrument panel or the like that is visible to the user. When the travelable distance information is input and the ignition switch 15 is turned on, a message including "travelable distance Me" is displayed on the main display 41 until the oil is changed and the reset operation is completed. Here, as an example of the message, "AT Fluid Service due in 1250 miles Exchange ATF at dealer (Please change the oil at the dealer after driving 1250 miles.)" is displayed. In addition to this visual display, for example, a message including "drivable distance Me" may be announced by voice each time the ignition switch 15 is turned on.

The sub-display 42 is a warning display that is arranged in an instrument panel or the like that is visible to the user. When the travelable distance information is input to the sub-display 42, regardless of whether the ignition switch is on or off, a display prompting the user to change the oil is displayed until the reset operation is completed after the oil is changed. For example, an icon indicating oil change or an oil change indicator lamp is lit or blinked.

[Oil deterioration estimation processing configuration]
FIG. 7 shows the flow of the oil deterioration estimation process executed by the oil deterioration estimation controller 110 of the transmission control unit 10. As shown in FIG. The configuration of the oil deterioration estimation processing will be described below with reference to FIGS. 7 to 9. FIG. It should be noted that the processing according to the flowchart of FIG. 7 is repeatedly executed at a predetermined control cycle.

In step S1, following the start, it is determined whether or not the oil temperature is equal to or higher than the first set value. If YES (oil temperature≧first set value), proceed to step S2, and if NO (oil temperature<first set value), proceed to step S3.

Here, the "oil temperature" is determined by slightly increasing the main temperature sensor value (or sub temperature sensor value) considering that the main substrate temperature sensor 31 (or sub substrate temperature sensor 32) is not directly immersed in the transmission oil. It is considered as the raised temperature. The “first set value” is set to a temperature (for example, about 50° C.) at which the rate of progression of oil deterioration increases when the oil temperature rises further.

In step S2, following the determination in step S1 that the oil temperature is greater than or equal to the first set value, an oil temperature heat count value Nco is calculated from the time t1 when the oil temperature exceeds the first set value and the heat count coefficient k1, Go to step S3.

Here, the "oil temperature heat count value Nco" is calculated by measuring the oil temperature once every 10 msec (time t1) and accumulating the heat count coefficient k1 of the average temperature for 1 min {Σ(k1×t1)}. value. The heat count coefficient k1 is given by a variable value that increases progressively as the oil temperature increases, as shown in FIG.

In step S3, following the determination in S1 that the oil temperature < the first set value, or the calculation of the oil temperature heat count value Nco in S2, the clutch portion estimated temperature is set to the second set value (> the first set value). ) to determine whether or not If YES (estimated clutch temperature≧second set value), proceed to step S4. If NO (estimated clutch temperature<second set value), proceed to step S5.

Here, the "estimated temperature of the clutch part" is, for example, the initial temperature of the clutch part as the oil temperature, the amount of heat generated according to the magnitude of the transmission torque and the magnitude of the clutch slip rotation speed, and the amount of heat dissipation due to complete engagement and complete disengagement. is calculated for each of the friction engagement elements (six pieces) based on. The "second set value" is set to a temperature (for example, about 250° C.) at which the deterioration of the oil accelerates when the temperature of the clutch portion rises further, such as during continuous shifting.

In step S4, following the determination in step S3 that the estimated clutch temperature is greater than or equal to the second set value, the clutch heat count value Ncc is calculated based on the time t2 when the estimated clutch temperature exceeds the second set value and the constant k2. Calculate and proceed to step S5.

Here, the "clutch heat count value Ncc" is the time t2 (in units of one second) at which the estimated clutch temperature reaches or exceeds the second set value when the estimated clutch temperature is measured once every 10 msec, and the constant k2. This value is calculated by accumulating {Σ(k2×t2)} of the multiplied values. As shown in FIG. 9, the constant k2 is a fixed value determined by experiments, etc., because the relationship between the heat count value of the clutch portion and the BN (base number), which is an index of oil deterioration, becomes a substantially proportional relationship due to the gradient γ. given by Further, when there are a plurality of frictional engagement elements whose clutch portion estimated temperature is equal to or higher than the second set value, the value obtained by adding the number of elements is set as the clutch portion heat count value Ncc.

In step S5, following the judgment in S3 that the clutch portion estimated temperature<the second set value, or the calculation of the clutch portion heat count value Ncc in S4, the oil temperature heat count value Nco and the clutch portion heat count value Ncc are calculated. is added to calculate the deterioration count value ΣNc, and the process proceeds to step S6.

In step S6, following the calculation of the deterioration count value ΣNc in S5, information on the calculated deterioration count value ΣNc is output to the oil change display controller 40, and the process proceeds to the end.

[Oil change display processing configuration]
FIG. 11 shows the flow of the oil change display process executed by the oil change display controller 40. As shown in FIG. The configuration of the oil change display processing will be described below with reference to FIGS. 10 and 11. FIG. It should be noted that the processing according to the flowchart of FIG. 11 is repeatedly executed at a predetermined control cycle.

In step S11, it is determined whether the ignition switch 15 is on. If YES (IGN ON), the process proceeds to step S13, and if NO (IGN OFF), the process proceeds to step S12.

In step S12, following the determination in S11 that the IGN is OFF, if the oil change display is being performed on the main display 41 according to the travelable distance Me, the oil change display is erased, and the process proceeds to END. Note that the oil replacement display on the sub-display 42 is maintained.

In step S13, following the determination that IGN is ON in S11, whether the deterioration count value ΣNc input from the oil deterioration estimation controller 110 is equal to or greater than the oil change display start threshold value Dth (<oil change necessary threshold value Rth). determine whether or not If YES (.SIGMA.Nc.gtoreq.Dth), proceed to step S14. If NO (.SIGMA.Nc<Dth), proceed to END.

Here, the "oil change necessary threshold value Rth" is determined in advance based on the experimental results obtained by conducting an experiment on the deterioration count value ΣNc and the degree of progression of oil deterioration. Then, as shown in FIG. 10, the "oil change display start threshold value Dth" determines the mileage Xd preceding the display section ΔX from the mileage Xr corresponding to the oil change necessary threshold value Rth. The count value is ΣNc. Note that the display section ΔX is set to, for example, about 2000 km, taking into account the distance to create a margin for prompting the driver to change the oil, the distance required to go to the dealer after making the decision to change the oil, and the like.

In step S14, following the judgment that ΣNc≧Dth in S13, it is judged whether or not it is the first time to judge that ΣNc≧Dth. If YES (first time), go to step S15. If NO (not first time), go to step S17.

In step S15, subsequent to the determination in step S14 that it is the first time, the initial value Me0 of the travelable distance when it is first determined that ΣNc≧Dth is calculated, and the process proceeds to step S16.

Here, the "initial value of possible mileage Me0" is the possible mileage from the oil change display start threshold value Dth to the oil change required threshold value Rth, and the upward gradient of the deterioration count value ΣNc with respect to the actual mileage thus far continues. Calculation is made assuming that

In step S16, subsequent to the calculation of the initial possible travel distance Me0 in S15, the initial value Me0 of the calculated possible travel distance and the distance measured by the odometer 44 when it was first determined that ΣNc≧Dth are stored, Go to step S18.

In step S17, following the judgment in S14 that it is not the first time, the travelable distance Me to be displayed on the main display 41 is calculated, and the process proceeds to step S18.

Here, the displayed travelable distance Me is
Displayed travelable distance Me=Initial value of travelable distance Me0-(current distance of odometer 44-distance of odometer 44 stored in S13)
It is calculated using the formula of It should be noted that (the current distance of the odometer 44 - the distance of the odometer 44 stored in S13) corresponds to the actual traveled distance after the start of display.

In step S18, following the calculation of the travelable distance Me to be displayed in S15 or S17, the travelable distance Me is displayed on the main display 41 and the sub-display 42, and an oil change display suggesting oil change is performed. Proceed to S19. Here, when the initial value of the travelable distance Me0 is calculated in S15, the initial value of the travelable distance Me0 is set as the travelable distance Me to be displayed.

In step S19, it is determined whether or not the reset operation by pressing the reset switch 43 for a long time is started after the user has changed the oil following the oil change display command in S18. If YES (the reset operation has been started), the process proceeds to step S20, and if NO (the reset operation has not been started), the process proceeds to END.

In step S20, following the determination in step S19 that the reset operation has started, reset information for resetting the deterioration count value ΣNc to zero is output to the oil deterioration estimation controller 110, and the process proceeds to step S21.

In step S21, following the output of the reset information in S20, it is determined whether or not the reset operation to the reset switch 43 has ended. If YES (the reset operation has been completed), the process proceeds to step S22, and if NO (the reset operation has not been completed), the process returns to step S20.

In step S22, following the determination in step S21 that the reset operation has been completed, the oil replacement display displayed on the main display 41 and the sub-display 42 is erased, and the process proceeds to END.

Next, "problems of the background art and measures for solving the problems" will be explained. The actions of the first embodiment will be described separately for the "oil deterioration estimation action" and the "oil replacement display action".

[Problem of background technology and solution to the problem]
Transmission oil, which is the transmission hydraulic fluid (ATF) of the automatic transmission, deteriorates due to long-term use. Vibration (judder) may occur in the clutch or brake. For this reason, it is necessary to notify the timing of oil replacement by means of a display prompting replacement of transmission oil with new transmission oil before the progress of oil deterioration reaches a limit range in which occurrence of vibration (judder) can be suppressed.

On the other hand, in the background technology, as shown in Fig. 12, the oil change timing based on the oil change display is determined based on the criteria of oil degradation (= ATF degradation) based on severe users, and the mileage (= Mileage) is specified. do. When the mileage reaches the designated distance, an oil change display informs the driver that it is time to change the oil.

However, when the oil change timing is specified by distance, there are problems as listed below.
(a) Market fleet data is scarce and it is difficult to make predictions based on mileage.
(b) Since oil temperature and time are the parameters for thermal deterioration of oil, when the travel distance is specified, variations in oil deterioration increase. For example, in the case of a severe user, the mileage M1 is specified, whereas in the case of a nominal user, the mileage M2 is the distance that reaches the criteria for the degree of oil deterioration. Furthermore, in the case of a mild user, the distance to reach the criteria for the degree of oil deterioration is the traveling distance M3 (>M2>M1). In other words, the hatched portion in FIG. 12 is the variation region of oil deterioration.
(c) When the specified mileage M1 is reached, the degree of oil deterioration does not reach the criteria, and users who do not need to change the oil are forced to change the oil, which imposes a heavy burden on the user.

With respect to the above-described background art, the current oil deterioration level is detected, and the current oil deterioration level is compared with an oil determination threshold value corresponding to the measured vehicle speed and oil temperature to determine the deterioration of the oil. An oil deterioration detection device (Japanese Patent Application Laid-Open No. 2009-138852) has been proposed that, when deterioration of the oil is detected, displays a prompt to replace the transmission oil.

However, in the prior art described above, an oil replacement warning is simply displayed at the timing of detection of oil deterioration. For this reason, the degree of urgency for the user to change the transmission oil may not be communicated, and depending on how the user receives the notification, the timing of the change may be off, and the deterioration of the oil may progress. Also, if a warning is issued at an early stage in order to prevent this, there is a problem that the user may misunderstand that the frequency of oil changes is high.

As a result of analysis of the current situation and consideration of problems, the inventors of the present invention have found that, firstly, when the oil deterioration estimated value calculated based on the oil temperature and time is specified, the oil deterioration varies more than when the distance is specified. become smaller. Secondly, it is effective to make the user aware of the degree of urgency until the transmission oil is changed by displaying the travelable distance until the oil change is reached before the oil change time is reached. I paid attention.

Based on the above points of attention, the present invention provides a vehicle-mounted automatic transmission 3 having a transmission control unit 10 that performs hydraulic system control using the transmission oil stored in the oil pan 6a. The transmission control unit 10 has an oil deterioration estimation controller 110 that calculates a deterioration count value ΣNc of the transmission oil based on the oil temperature and time. An oil change display controller 40 is provided for inputting the deterioration count value ΣNc from the oil deterioration estimation controller 110 and displaying oil change information. The oil change display controller 40 sets an oil change display start threshold Dth based on the degree of oil deterioration before reaching the oil change necessary threshold Rth as the oil deterioration determination threshold. When the deterioration count value ΣNc reaches the oil change display start threshold value Dth, display of the travelable distance Me that can be traveled until the oil change necessary threshold value Rth is reached is started. After starting the display of the travelable distance Me, a problem-solving measure is adopted in which the travelable distance Me, which decreases according to the actual travel distance after the start of display, is displayed regardless of the deterioration count value ΣNc.

That is, when specifying a degradation count value calculated based on the oil temperature and time, which are thermal degradation parameters of the transmission oil, it is possible to suppress variation in oil degradation due to user types to be smaller than when specifying a distance.

By displaying the travelable distance Me up to the oil replacement before reaching the oil replacement time, the user can be made to recognize the travelable distance Me from an earlier timing than the time when the oil replacement is actually required. In other words, the degree of urgency until the transmission oil is changed is conveyed to the user by recognizing the indication that the travelable distance Me until the oil change is shortened. Since it is possible to know when to change the transmission oil from the travelable distance Me, the user can change the transmission oil at an appropriate timing. For this reason, it is possible to prevent the deterioration of the transmission oil from progressing due to the time it takes to change the oil, and the misunderstanding by the user that the oil is changed frequently.

Furthermore, since the possible travel distance Me, which decreases in accordance with the actual travel distance after the start of display, is displayed regardless of the deterioration count value ΣNc, it is possible to prevent the user such as the driver from feeling uncomfortable. For example, when the travelable distance Me after the start of display is reduced by the deterioration count value ΣNc, it may suddenly decrease or not decrease regardless of the actual travel distance, and the amount of decrease in the travelable distance Me may vary. become. This difference in the amount of decrease gives a sense of discomfort to the user.

As a result, when the deterioration of the transmission oil progresses, it is possible to present oil change information that does not give the user a sense of discomfort while preventing the oil change timing from being overlooked and the oil change frequency from increasing. In addition, since the drivable distance Me until the oil change is displayed, it is possible to reduce the burden on the user as compared with the case where the oil change warning is suddenly displayed at the timing when the oil change is required.

[Oil deterioration estimation action]
First, based on the flow chart shown in FIG. 7, the action of the oil change determination process will be described. For example, when the oil temperature of the transmission oil in the oil pan becomes equal to or higher than the first set value due to long running, the process proceeds from S1 to S2. In S2, the oil temperature heat count value Nco is calculated from the time t1 when the oil temperature reaches or exceeds the first set value and the heat count coefficient k1. If the oil temperature is less than the first set value, the process proceeds from S1 to S3, and the oil thermal heat count value Nco is not calculated.

For example, when the estimated temperature of the clutch portion of the frictional engagement element, which is repeatedly engaged/disengaged due to continuous shifting, becomes equal to or higher than the second set value (>first set value), the process proceeds from S3 to S4. In S4, the clutch heat count value Ncc is calculated from the time t2 at which the estimated clutch temperature is equal to or higher than the second set value and the constant k2. If the clutch portion estimated temperatures of all the friction engagement elements are less than the second set value, the process proceeds from S3 to S5, and the clutch portion heat count value Ncc is not calculated.

Next, when proceeding from S3 or S4 to S5→S6, in S5, the deterioration count value ΣNc is calculated by adding the oil temperature heat count value Nco and the clutch portion heat count value Ncc, and in S6, the deterioration count value ΣNc is calculated. It is output to the oil change display controller 40 .

As described above, the oil deterioration degree estimation value for estimating the degree of deterioration of the transmission oil is the oil thermal deterioration progress value based on the oil temperature and time of the transmission oil, and the estimated temperature of the shift clutch portion of the automatic transmission 3. A cumulative heat deterioration progression value is obtained by summing the clutch portion heat deterioration progression value based on time.

That is, the inventors of the present invention have found that the temperature of the shift clutch increases to a high temperature level due to continuous shifting or the like, and if the high temperature continues for a long period of time, it becomes a cause of thermal deterioration of the transmission oil. Therefore, for example, if the estimated oil deterioration level is only the oil temperature heat deterioration progression value calculated based on the oil temperature and time of the transmission oil, the temperature of the gear shift clutch unit rises to a high temperature level due to continuous gear shifting, etc. It is not possible to cope with the thermal deterioration of the transmission oil caused by the

On the other hand, if the oil deterioration degree estimated value is set to a cumulative heat deterioration progress value obtained by summing the oil temperature heat deterioration progress value and the clutch portion heat deterioration progress value, the oil temperature rise of the transmission oil in the oil pan 6a and the speed change It is possible to cope with the thermal deterioration of the transmission oil caused by both the temperature rise of the clutch portion. Therefore, when calculating the accumulated heat deterioration progress value, two different causes of heat deterioration of the transmission oil are reflected, and a value can be calculated with little variation depending on the user type.

Furthermore, the "oil temperature heat deterioration progression value" is an oil temperature heat count value Nco calculated from the heat count coefficient k1 determined by the time t1 when the oil temperature exceeds the first set value and the oil temperature. The "clutch heat deterioration progression value" is the clutch heat count value Ncc calculated from the time t2 at which the estimated temperature of the shift clutch reaches a second set value higher than the first set value and a constant k2. The "accumulated heat deterioration progression value" is the deterioration count value ΣNc obtained by adding the oil temperature heat count value Nco and the clutch portion heat count value Ncc.

That is, the present inventors have found that the higher the oil temperature of the transmission oil in the oil pan, the higher the degree of thermal deterioration of the transmission oil (see FIG. 8). Further, the inventors have found that the longer the temperature rise time of the transmission clutch portion, the more the thermal deterioration of the transmission oil progresses proportionally (see FIG. 9).

Reflecting the above knowledge, the oil temperature heat count value Nco is calculated from the heat count coefficient k1 determined by the time t1 when the oil temperature reaches or exceeds the first set value and the oil temperature. On the other hand, the clutch portion heat count value Ncc is calculated from the time t2 at which the estimated temperature of the transmission clutch portion exceeds the second set value and the constant k2. Therefore, when calculating the deterioration count value .SIGMA.Nc, the thermal deterioration progression characteristics of two different transmission oils are reflected, and a value can be calculated with little variation depending on the user type.

For example, as shown in Fig. 13, the oil change timing is determined based on the oil change display. Based on severe users, the criteria for oil degradation (=ATF degradation) are determined, and the degradation count value (=Cumulative heat count value) is specified. Then, when the mileage reaches the designated deterioration count value, the oil change display informs the user that it is time to change the oil. In this case, there are advantages listed below.
(a) Since oil thermal deterioration parameters are oil temperature and time, when the deterioration count value is specified, oil deterioration variation can be kept small. For example, deterioration count value C1 is designated for severe users, deterioration count value C2 is designated for nominal users, and deterioration count value C3 is designated for mild users. In other words, the hatched portion in FIG. 13 is the oil deterioration variation region, which is much smaller than the hatched portion in FIG. 12 .
(b) When the designated deterioration count value C1 is reached, the user is notified of the time to change the oil. Therefore, the user is not forced to change the oil when it is deemed unnecessary, thereby reducing the burden on the user.

In addition, when the deterioration count value ΣNc reaches the oil change indication start threshold value Dth, it is assumed that the increase gradient of the deterioration count value ΣNc with respect to the actual traveling distance continues until the oil change necessary threshold value Rth is reached. is calculated by estimating

That is, the slope of increase of the deterioration count value ΣNc with respect to the actual travel distance reflects whether the user type is a severe user or a mild user. Therefore, if the travelable distance Me is calculated assuming that the deterioration count value ΣNc continues to rise with respect to the actual travel distance, it is possible to calculate the accurate travelable distance Me that directly reflects the difference in user type.

[Oil change indication function]
First, the action of the oil replacement display processing will be described based on the flow chart shown in FIG. When the deterioration count value ΣNc is determined to be equal to or greater than the oil change display start threshold value Dth while the ignition is on and the determination ΣNc≧Dth is experienced for the first time, the process proceeds to S11→S13→S14→S15→S16→S18. At S15, the initial value Me0 of the travelable distance when it is first determined that ΣNc≧Dth is calculated. In S16, the initial value Me0 of the calculated possible running distance and the distance measured by the odometer 44 when it is first determined that ΣNc≧Dth are stored. In S18, the main display 41 and the sub-display 42 display an oil change display based on the travelable distance Me (-=the initial value of the travelable distance Me0).

When the deterioration count value ΣNc is determined to be equal to or greater than the oil change display start threshold value Dth while the ignition is on, and the determination ΣNc≧Dth is experienced multiple times, the process proceeds to S11→S13→S14→S17→S18. At S17, the travelable distance Me to be displayed on the main display 41 is calculated by subtracting the actual traveled distance after the start of display from the initial value Me0 of the travelable distance. In S18, an oil change display is performed on the main display 41 and the sub-display 42 based on the travelable distance Me calculated in S16.

After the oil change according to the travelable distance Me is displayed on the main display 41 and the sub-display 42 in S18, if the user does not start the reset operation, the process proceeds from S18 to S19 → END, and the oil is changed according to the travelable distance Me. Display continues. However, when the user who confirmed the travelable distance Me changed the oil and then started resetting the reset switch 43, the process proceeds from S19 to S20→S21. In S<b>20 , reset information for resetting the deterioration count value ΣNc to zero is output to the oil deterioration estimation controller 110 . In S21, it is determined whether or not the reset operation has ended. When it is determined in S21 that the resetting operation has been completed, the process proceeds to S22, and in S22, the oil change display based on the possible travel distance Me displayed on the main display 41 and the sub-display 42 is erased.

Next, the oil replacement display function will be described with reference to the time chart shown in FIG. Time T1, time T2, and time T3 are the ignition ON/OFF times during which the degradation count value ΣNc equal to or greater than the oil replacement display start threshold value Dth is not input from the oil degradation estimation controller 110 .

Time T4 is the time when the deterioration count value ΣNc equal to or greater than the oil replacement display start threshold value Dth is input from the oil deterioration estimation controller 110 . At time T4, when the deterioration count value ΣNc that is equal to or greater than the oil change display start threshold value Dth is input and the travelable distance Me is calculated, the oil change display based on the travelable distance Me is started on the main display 41, and the ignition is turned on. The display continues until time T5 when the ignition is switched off. Then, the oil replacement display on the sub-display 42 starts from time T4.

After that, from the middle of the ignition ON time T6 to the OFF time T7, from the middle time of the ignition ON time T8 to the OFF time T9, and from the middle time of the ignition ON time T10 to the OFF time T11, the main display 41 displays the oil change according to the travelable distance Me. be done.

Then, it is assumed that the oil was changed by the user at time T12, and the ignition was turned on at time T13. At this time, on the condition that the user changes the oil and turns on the ignition switch 15, reset operation of the oil change display is permitted. Then, when the reset operation is started at time T14, reset information for resetting the deterioration count value ΣNc to zero is output to the oil deterioration estimation controller 110 . When the reset operation is finished at time T15, the oil replacement display displayed on the main display 41 and the sub-display 42 is erased.

That is, when the travelable distance Me is calculated, the travelable distance Me is displayed on the main display 41 while the ignition is on. Therefore, just by visually recognizing the display on the main display 41, the user can obtain change information of the travelable distance Me that allows the vehicle to travel without oil change each time the ignition is turned on.

Further, when the user changes the oil and starts the operation of canceling the display while the ignition is on, the oil change display controller 40 outputs a reset signal to zero the deterioration count value ΣNc to the oil deterioration estimation controller 110 . . When the display canceling operation is completed while the ignition is on, the display on the main display 41 and the sub-display 42 is erased.

That is, when the display cancellation operation is started while the ignition is ON, the deterioration count value ΣNc is reset to zero, and when the display cancellation operation is completed while the ignition is ON, the displays on both displays 41 and 42 are erased. Therefore, after the user has changed the oil, only by performing the display cancellation operation, it is possible to return to the initial state of the oil change determination and the oil change display with the newly changed transmission oil.

As described above, the oil change display device for the automatic transmission 3 of the first embodiment has the following effects.

(1) An automatic transmission 3 including a transmission control unit 10 that performs hydraulic system control using transmission oil stored in an oil pan 6a,
The transmission control unit 10 has an oil deterioration estimation controller 110 that calculates an estimated oil deterioration level (deterioration count value ΣNc) of the transmission oil based on the oil temperature and time,
An oil change display controller 40 is provided for inputting an oil deterioration degree estimated value (deterioration count value ΣNc) from the oil deterioration estimation controller 110 and displaying oil change information,
The oil change display controller 40 sets an oil change display start threshold Dth according to the degree of oil deterioration before reaching the oil change necessary threshold Rth as the oil deterioration determination threshold,
When the oil deterioration degree estimated value (deterioration count value ΣNc) reaches the oil change display start threshold value Dth, the display of the travelable distance Me that can be traveled until reaching the oil change necessary threshold value Rth is started,
After starting the display of the travelable distance Me, the travelable distance Me that decreases according to the actual travel distance after the start of display is displayed regardless of the oil deterioration level estimated value (degradation count value ΣNc).
Therefore, when the deterioration of the transmission oil progresses, it is possible to present oil change information that does not give the user a sense of discomfort while preventing the oil change timing from being overlooked and the oil change frequency from increasing.

(2) The oil deterioration estimating controller 110 calculates the oil deterioration degree estimation value from an oil temperature heat deterioration progress value (oil temperature heat count value Nco) based on the oil temperature of the transmission oil, and an estimation of the shift clutch portion of the automatic transmission 3. A cumulative heat deterioration progression value (deterioration count value ΣNc) is obtained by summing the clutch heat deterioration progression value (clutch heat count value Ncc) based on the temperature.
For this reason, when calculating the cumulative heat deterioration progress value (degradation count value ΣNc), two different causes of thermal degradation of the transmission oil are reflected, and the cumulative heat degradation progress value (degradation count value ΣNc) is highly accurate with little variation depending on the user type. A deterioration count value ΣNc) can be calculated.

(3) The oil deterioration estimating controller 110 sets the oil temperature heat deterioration progression value to the oil temperature heat count value Nco calculated from the time t1 when the oil temperature exceeds the first set value and the heat count coefficient k1 determined by the oil temperature,
A clutch heat deterioration progression value is defined as a clutch heat count value Ncc calculated from a constant k2 and a time t2 at which the estimated temperature of the transmission clutch exceeds a second set value higher than the first set value,
The cumulative heat deterioration progression value is defined as a deterioration count value ΣNc obtained by summing the oil temperature heat count value Nco and the clutch portion heat count value Ncc.
For this reason, when calculating the deterioration count value ΣNc, even the thermal deterioration progress characteristics of two different transmission oils are reflected, and the highly accurate deterioration count value ΣNc can be calculated with little variation depending on the user type.

(4) When the deterioration count value ΣNc reaches the oil change display start threshold value Dth, the oil change display controller 40 changes the initial value Me0 of the travelable distance that can be traveled up to the oil change necessary threshold value Rth from the actual traveled so far. The estimation is calculated on the assumption that the upward gradient of the deterioration count value ΣNc with respect to the distance continues.
Therefore, when sequentially calculating the travelable distance Me that decreases after the deterioration count value ΣNc reaches the oil change display start threshold value Dth, the accurate travelable distance Me that reflects the difference in user type is calculated. be able to.

(5) The oil change display controller 40 displays the travelable distance Me on the display (main display 41) while the ignition is on.
For this reason, the change information of the travelable distance that allows the user to travel without oil change is acquired only by visually recognizing the display on the display (main display 41) each time the ignition is turned on. be able to.

(6) The oil change display controller 40 sends an estimated oil deterioration level (deterioration count value ΣNc) to the oil deterioration estimation controller 110 when the user changes the oil and starts the operation to cancel the display while the ignition is on. Output a reset signal to zero,
When the display canceling operation is completed while the ignition is on, the display on the display (main display 41, sub-display 42) is erased.
Therefore, after the user has changed the oil, only by performing the display canceling operation, it is possible to return to the initial state of the oil change determination and the oil change display with the newly changed transmission oil.

The oil change display device for an automatic transmission according to the present invention has been described above based on the first embodiment. However, the specific configuration is not limited to the first embodiment, and design changes and additions are permitted as long as they do not deviate from the gist of the invention according to each claim of the scope of claims.

In the first embodiment, as the oil deterioration degree estimation value, the oil temperature heat count value Nco based on the oil temperature of the transmission oil and the clutch portion heat count value Ncc based on the estimated temperature of the shift clutch portion of the automatic transmission 3 are added. An example is shown in which the deterioration count value ΣNc is assumed to be the same. However, as an oil deterioration degree estimation value, only an oil thermal heat count value based on the oil temperature of the transmission oil may be used. Furthermore, an example of determining the deterioration count value by adding a correction due to a change in the components of the transmission oil to the heat count value based on the temperature may be used.

In the first embodiment, an example of the automatic transmission 3 having nine forward speeds and one reverse speed is shown as the automatic transmission. However, the automatic transmission may be an automatic transmission having stepped gear stages other than 9 forward speeds and 1 reverse speed, or may be a continuously variable transmission. A continuously variable transmission with an auxiliary transmission combined with a transmission may be used.

Embodiment 1 shows an example of an oil change display device for an automatic transmission 3 mounted on an engine vehicle. However, it can be applied not only to engine vehicles, but also to an oil change display device for automatic transmissions mounted on hybrid vehicles, electric vehicles, and the like.

1 engine 2 torque converter 3 automatic transmission
B1 1st brake (shift clutch)
B2 2nd brake (shift clutch)
B3 3rd brake (shift clutch)
K1 1st clutch (shifting clutch)
K2 2nd clutch (shift clutch)
K3 3rd clutch (shifting clutch)
10 transmission control unit 100 transmission controller 110 oil deterioration estimation controller 15 ignition switch 31 main board temperature sensor 32 sub board temperature sensor 40 oil change display controller 41 main display (display display)
42 sub display (display display)
43 Reset switch 44 Odometer 50 CAN communication line 6 Control valve unit 6a Oil pan

Claims (5)

An automatic transmission including a transmission control unit that performs hydraulic control using transmission oil stored in an oil pan,
The transmission control unit has an oil deterioration estimation controller that calculates an oil deterioration degree estimation value of the transmission oil based on oil temperature and time,
An oil change display controller for inputting the oil deterioration degree estimated value from the oil deterioration estimation controller and displaying oil change information,
The oil change display controller sets an oil change display start threshold according to the degree of oil deterioration before reaching the oil change necessary threshold as the oil deterioration determination threshold,
When the estimated oil deterioration level reaches the oil change display start threshold, the display of the travelable distance that can be traveled until reaching the oil change necessary threshold is started,
Displaying the travelable distance that decreases according to the actual traveled distance after the start of display regardless of the oil deterioration estimated value after the display of the travelable distance is started ,
The oil deterioration estimating controller divides the estimated oil deterioration degree value into an oil temperature heat deterioration progress value based on the oil temperature of the transmission oil, and a clutch portion heat deterioration progress value based on the estimated temperature of the shift clutch portion of the automatic transmission. An oil change display device for an automatic transmission, characterized in that a cumulative heat deterioration progress value obtained by adding In the oil change display device for an automatic transmission according to claim 1 ,
The oil deterioration estimating controller sets the oil temperature heat deterioration progress value as an oil temperature heat count value calculated by a heat count coefficient determined by the time when the oil temperature becomes equal to or higher than a first set value and the oil temperature,
The clutch heat deterioration progress value is a clutch heat count value calculated from a constant and the time during which the estimated temperature of the speed change clutch reaches a second set value higher than the first set value,
An oil change display device for an automatic transmission, wherein the accumulated heat deterioration progress value is a deterioration count value obtained by adding the oil temperature heat count value and the clutch portion heat count value. In the oil change display device for an automatic transmission according to claim 2 ,
When the deterioration count value reaches the oil change display start threshold value, the oil change display controller sets the initial value of the travelable distance that can be traveled up to the oil change necessary threshold value to the actual travel distance so far. An oil change display device for an automatic transmission, characterized in that estimation calculation is performed on the assumption that the rising gradient of the count value continues. In the oil change display device for an automatic transmission according to any one of claims 1 to 3 ,
An oil change display device for an automatic transmission, wherein the oil change display controller displays the travelable distance on a display while the ignition is on. In the oil change display device for an automatic transmission according to claim 4 ,
The oil change display controller outputs a reset signal to the oil deterioration estimation controller to set the oil deterioration degree estimated value to zero when the user changes the oil and starts the display cancellation operation while the ignition is on. ,
An oil change display device for an automatic transmission, wherein the display on the display display is cleared when the display cancellation operation is completed while the ignition is on.

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