JP2008128438A - Shift control device for transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shift control device for transmission, which ensures a desired life in conformity with each specification even in a transmission of the same structure which need not be enhanced in strength or durability more than necessary. <P>SOLUTION: In the shift control device, an actual shift load Fx is determined from a driving condition of an automobile or the like, and a shifting frequency Nx according to the actual shift load Fx is calculated. An allowable shift load is calculated from a shift frequency Nlim satisfying an equation (1): α(Lold-1/Nx)=(Nref-ΣN)/Nlim to limit the actual shift load. In the equation (1), α represents a coefficient, Lold represents the remaining life of the transmission at the time of completion of the previous shifting operation, Nx represents the shift frequency ensured in shifting operation with the shift load Fx, Nref represents the shift frequency ensured in shifting operation with general traveling shift load Fref, ΣN represents the accumulated shift frequency, and Nlim represents the ensured shift frequency needed in the remaining life. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a shift control apparatus for a transmission that performs a shift change operation by an actuator. In particular, the present invention relates to a measure for optimizing a “shift load” that is a driving force of an actuator for executing a shift change operation.

  For example, as disclosed in Patent Document 1 below, actuators (clutch actuators and shift change actuators) such as electric motors and hydraulic cylinders are added to the configuration of a conventional manual transmission, and clutch engagement is performed by these actuators. There is known a transmission that performs a disengagement operation or a shift change operation.

According to this transmission (hereinafter sometimes referred to as transmission)
1) The clutch operation can be automated.

  2) When selecting the “automatic transmission mode”, an automatic shift change operation is performed by selecting the optimum gear according to the travel conditions such as the accelerator opening and the vehicle speed, as in the case of the automatic transmission (automatic transmission). This makes it possible to achieve both low fuel consumption and easy drive, which are superior to those of automatic transmission vehicles.

  3) When the “manual shift mode” is selected, a shift change operation is performed based on a shift instruction signal by a driver's shift lever operation (upshift, downshift), and this provides a light and direct feeling unique to a manual transmission vehicle. Sporty driving is possible and driving intended by the driver becomes possible.

  Further, as this type of transmission, there is provided one having only one of the “automatic transmission mode” and the “manual transmission mode”, or a clutch pedal, and an electric signal based on the operation of this clutch pedal. A device that operates a clutch actuator (clutch-by-wire type) is also known.

  Also, this type of transmission is similar to a normal manual transmission in that a synchronizer ring or the like is connected to the main shaft by a shift fork in order to select a gear that transmits power from the gear on the main shaft and the gear on the counter shaft. It is configured to slide in the axial direction. For this reason, an operating force (hereinafter referred to as a shift load) from the shift change actuator is applied to the shift fork, whereby a shift change operation is performed.

  From the viewpoint of shortening the time required for the shift change, the shift load is preferably set higher. However, the higher the shift load, the higher the load applied to each part of the transmission. It leads to shortening the life of the machine. That is, the increase in shift load and the extension of the life of the transmission are in a mutually contradictory relationship.

  For this reason, the shift load is actually changed according to the driving conditions (vehicle speed, accelerator opening, etc.) of the automobile and the external environment (outside air temperature, etc.). For example, in Patent Document 2 below, the shift load is increased as the oil viscosity increases in accordance with a change in oil viscosity corresponding to a change in outside air temperature.

  By the way, as a durability of a transmission mounted on an automobile, it is necessary to guarantee a predetermined number of shift change operations. For example, when guaranteeing a shift change operation of 500,000 times, it is necessary to have a configuration in which the shift change operation of 500,000 times can be satisfactorily performed without damaging the transmission.

  However, the driving state of the automobile varies depending on the driver, and the use situation of the transmission is also greatly different. For example, in the case of a driver who frequently performs rapid acceleration and rapid deceleration, the shift load is often used at a high value. In the case of the technique disclosed in Patent Literature 2, the shift load is often used at a high value in a situation where the technology is used in a cold region. On the other hand, in the case of a driver that does not perform rapid acceleration or rapid deceleration, the shift load is often used at a low value.

  Until now, in order to ensure the above-mentioned guaranteed number of shifts regardless of the state of use of the transmission (for example, even when the shift load is always used at a high value), the configuration of the transmission is high. It was designed to obtain strength and ensure sufficient durability.

In addition, each time a vehicle is shipped, a transmission having strength and durability suitable for the state of use of the transmission in the region (for example, the country of the export destination) is individually manufactured. In other words, a highly durable transmission shipped to an area where the shift load is used at a relatively high value, and a small and lightweight transmission shipped to an area where the shift load is used at a relatively low value. The machine was manufactured separately.
JP 2006-29465 A JP-A-2005-147302

  However, as described above, when the transmission is designed so that the guaranteed number of shifts can be ensured regardless of the state of use of the transmission, it is shipped to a region where the shift load is used at a relatively low value. As a transmission, the size and weight of the transmission are increased more than necessary, which is wasteful and leads to an increase in cost.

  In addition, when designing a transmission for each destination, it is necessary to design and manufacture many types of transmissions, which is not only complicated, but also makes it difficult to reduce costs due to mass production effects.

  The present invention has been made in view of the above points, and the object of the present invention is to adapt to each destination even in the case of a transmission having the same configuration that does not need to have higher strength and durability than necessary. An object of the present invention is to provide a shift control device for a transmission that can ensure a desired life by performing the above operation.

-Solving principle-
The solution principle of the present invention taken in order to achieve the above object is to estimate the remaining life of the transmission from the cumulative number of past shift changes and respective shift loads, and to reach this remaining life. By obtaining an allowable shift load for enabling execution of the number of shift changes that should be guaranteed, the shift load of the actuator can be limited to the allowable shift load or less.

-Solution-
Specifically, according to the present invention, the “shift load” applied from the actuator to the speed change operation unit can be changed, and power is transmitted from the drive source to the wheels by the operation of the speed change operation unit by this “shift load”. A shift control device for a transmission that executes a shift change operation for changing a gear to be performed is assumed. Remaining life estimation means for estimating the remaining life of the transmission from the cumulative value of the “shift load” and the number of shifts in the shift change operation executed in the past for the shift control device of the transmission, and the remaining life estimation means And an allowable shift load calculating means for calculating an “allowable shift load” that is an upper limit regulation value of the “shift load” based on the remaining life of the transmission estimated by the above.

  According to this specific matter, the remaining life of the transmission is estimated from the “shift load” and the cumulative value of the number of shifts in the previously performed shift change operation, and even if the number of shift changes to be guaranteed is the same. The “allowable shift load” is calculated as a lower value as the remaining life is shorter. As a result, the shift change operation of the transmission can be executed with the shift load for enabling the guaranteed number of shift changes to be achieved. In other words, when the remaining life is relatively long, the “allowable shift load” can be calculated as a relatively high value, allowing the actuator “shift load” to be set high, whereas the remaining life is relatively long. If it is short, the “allowable shift load” is calculated as a relatively low value, which limits the “shift load” of the actuator. This avoids situations where the transmission reaches the end of its life (causes breakage or failure) before reaching the guaranteed number of shift changes, regardless of the transmission usage at the shipping destination and the environment. The reliability of the transmission can be ensured.

Moreover, the following structure is mentioned as another solution means for achieving the said objective. First, the “shift load” applied from the actuator to the speed change operation unit can be changed, and the gear that performs power transmission from the drive source to the wheels is changed by the operation of the speed change operation unit by this “shift load”. Assume a shift control device for a transmission that performs a change operation. For the shift control device of this transmission, the following equation (1),
α (Lold−1 / Nx) = (Nref−ΣN) / Nlim (1)
(Α: coefficient, Lold: remaining life of transmission at end of previous shift change operation, Nx: number of shifts guaranteed when shift change operation is performed with shift load (Fx) (shift load (Fx) is The actual shift load when the shift change operation is executed), Nref: the number of shifts guaranteed when the shift change operation is performed with the shift load (Fref) during normal driving (the shift load (Fref) is determined by hardware design) Standardized shift load), ΣN: cumulative shift count, Nlim: guaranteed shift count required for remaining life)
An allowable shift load calculating means for calculating an allowable shift load (Flim) corresponding to the number of shifts (Nlim) is provided.

  With this specific matter, if the shift change operation is performed with a “shift load” equal to or less than the calculated allowable shift load (Flim), the number of shifts (Nlim) can be achieved. In other words, it is possible to avoid the situation where the transmission reaches the end of its life (causing damage or failure) before the guaranteed number of shift changes is reached. Therefore, it is possible to ensure the reliability of the transmission.

  Specifically, the “allowable shift load” calculated by the allowable shift load calculation means is used as a configuration for obtaining the “shift load” that the actuator actually applies to the speed change operation unit after the “allowable shift load” is calculated. When the "allowable shift load" is calculated as a value higher than the "maximum allowable shift load" by comparing the "load" with the "maximum allowable shift load", which is the limit shift load that causes the transmission to break. A shift load limiting means for limiting the “shift load” of the actuator to a value equal to or less than the “maximum allowable shift load” is provided.

  The “maximum allowable shift load” of the transmission is a load that may damage the transmission when a shift change operation is performed with a load higher than this load. In this solution, even if the “allowable shift load” is obtained as a high value, if the value is higher than the “maximum allowable shift load”, this “maximum allowable shift load” is not exceeded. Thus, the “shift load” of the actuator is limited. This avoids the situation where the transmission reaches the end of its life before reaching the guaranteed number of shift changes, and the “shift load” is too high (the above “maximum allowable shift load” is exceeded). B) The situation where the transmission is damaged can be avoided. In other words, according to the present solution, it is possible to guarantee the operation of the transmission from both the strength side of the transmission and the lifetime of fatigue.

  As the execution timing of the “allowable shift load” calculation operation by the allowable shift load calculation means, specifically, every time a predetermined shift change is performed (for example, every 1000 times) or every time a shift change operation is executed To execute. In the former case (calculation of “allowable shift load” for each predetermined number of shift changes), it is possible to suppress the “allowable shift load” from fluctuating abruptly. It is possible to avoid a situation in which a sense of incongruity is given. On the other hand, in the latter case ("allowable shift load" calculation every time a shift change operation is performed), it becomes possible to always obtain the optimum "allowable shift load", and the "allowable shift load" is too large or too small. Can be avoided.

  Further, as the operation for estimating the remaining life of the transmission by the remaining life estimating means, specifically, it is guaranteed when the shift change operation is continuously performed with the “shift load (F)” and the “shift load”. The remaining life of the transmission is estimated from the “F / N diagram” for obtaining the relationship with the number of shifts (N). This makes it possible to accurately determine the remaining life of the transmission by a relatively simple method.

  In the present invention, the remaining life of the transmission is estimated from the cumulative number of past shift changes and the respective shift loads, and the number of shift changes that should be guaranteed before the remaining life is reached can be executed. An allowable shift load is obtained, and the shift load of the actuator can be limited to the allowable shift load or less. For this reason, it is possible to avoid the situation where the transmission reaches the end of its life before reaching the guaranteed number of shift changes, and the same transmission that does not need to have higher strength and durability than necessary. Even so, it is possible to ensure a desired life by setting the shift load suitable for each destination.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a case will be described in which the present invention is applied to an automobile equipped with an SMT (Sequential Manual Transmission) in which clutch engagement / disconnection (intermittent) operation and transmission shift change operation are executed by an actuator.

  Further, in the present embodiment, an explanation will be given by taking as an example a transmission that includes an “automatic transmission mode” and a “manual transmission mode”, and each mode can be switched. However, a transmission that includes only one of the modes is described. The present invention can also be applied to a machine. In the above "automatic shift mode", the optimum gear is selected according to the travel conditions such as the accelerator opening and the vehicle speed, and the clutch engagement / disengagement operation and gear change are automatically performed (without requiring the driver's operation). This is the mode in which the machine shift changes. On the other hand, the “manual shift mode” is a mode in which each of the actuators described later is driven in accordance with the shift lever operation of the driver to perform the clutch disengagement operation and the shift change operation of the transmission.

(Powertrain and control system configuration)
FIG. 1 is a diagram showing a schematic configuration of a power train and a control system of an FR (front engine / rear drive) type vehicle according to the present embodiment, and FIG. 2 shows an SMT control unit (SMT ECU) 6 and an engine control unit ( It is a block diagram which shows the structure of the control system relevant to E / G ECU) 7.

  As shown in FIG. 1, a transmission 3 is connected to an output shaft (crankshaft) 11 of an engine (drive source) 1 via a clutch mechanism 2 as a power train of an automobile. The output side of the transmission 3 is connected to drive wheels 44 and 44 via a propeller shaft 41, a differential gear 42 and drive shafts 43 and 43.

  The clutch mechanism 2 is configured as a so-called automatic clutch, and includes a friction clutch and a clutch actuator 21 including an electric motor that changes the engagement state of the friction clutch. The clutch actuator 21 is driven to rotate in the forward and reverse directions to change the contact / separation state of the friction clutch. The clutch actuator 21 may be a hydraulic cylinder.

  The transmission 3 includes a reverse gear stage, a plurality of forward gear stages, and a gear shift actuator 31, and a mechanism for switching the meshing state (power transmission path) of each gear mechanism by driving the actuator 31. It has become. Specifically, the synchronizer ring provided on the main shaft is slid in the axial direction by an operating force (shift load) applied from the actuator 31 to a shift fork (shift operation unit) (not shown) to transmit power between the gears. The reduction ratio is changed by switching the route. Since the configuration for changing the reduction ratio in accordance with the slide movement of the synchronizer ring is well known, description thereof is omitted here.

  As described above, the transmission 3 is configured to add on the actuator 31 to the configuration of the manual transmission, and execute a shift change operation by the actuator 31. A hydraulic cylinder can also be used as the actuator 31.

  As a result, the rotational output of the engine 1 is input to the transmission 3 via the clutch mechanism 2, and is transmitted to the propeller shaft 41 after being decelerated at a predetermined reduction ratio in the transmission 3. The rotation of the propeller shaft 41 is transmitted to the left and right drive wheels 44, 44 via the differential gear 42 and the drive shafts 43, 43.

  On the other hand, a shift operation section 5 having a shift lever (not shown) that can be operated by a driver is provided in the center console portion of the vehicle interior. FIG. 1 shows the shape of a shift gate that guides the operation of the shift lever. The shift gate shift patterns include reverse travel position (R position), neutral position (N position), automatic shift position (E position), manual shift position (M position), and upshift (+) at this M position, The driver can select the downshift (−). At this time, an operation of upshifting the transmission 3 is performed by operating the “+” side that is the forward direction of the driver, and a downshifting operation of the transmission 3 is performed by operating the “−” side of the opposite direction. When the shift lever is operated to the “+” side or the “−” side, the driver returns to the neutral M position by releasing the hand from the shift lever. The upshift means that the gear stage is switched so that the gear ratio of the transmission 3 (reduction ratio = the amount of rotation of the input shaft of the transmission / the amount of rotation of the output shaft of the transmission) becomes a smaller value. Downshift means that the gear position is switched so that the gear ratio becomes a larger value.

  The shift pattern shown in FIG. 1 is a right handle shift pattern, and the left handle pattern is a symmetrical pattern.

  Note that the shift pattern of the shift gate is not limited to that described above, and can be arbitrarily set. For example, a transmission that does not have the “automatic transmission mode” has a shift pattern that does not include the automatic transmission position (E position).

  The shift lever operation information as described above is given to the SMT controller 6. The SMT controller 6 controls the actuators 21 and 31 based on the operation information of the shift lever. That is, when the shift lever is in the automatic shift position, the clutch actuator 21 of the clutch mechanism 2 and the shift & select actuator 31 of the transmission 3 are operated according to the travel conditions such as the accelerator opening and the vehicle speed, and the automatic shift is performed. A change operation is performed. On the other hand, when the shift lever is in the manual shift position, the clutch actuator 21 of the clutch mechanism 2 and the shift & select actuator 31 of the transmission 3 are operated in accordance with the operation position of the shift lever operated by the driver. Operation is performed.

  On the other hand, the engine control unit 7 that controls the engine 1 includes information on the operation amount of the accelerator pedal 7A detected by the accelerator position sensor 71 and the engine speed detected by the engine speed sensor 72 (see FIG. 2). Information or the like is given, and based on these, the engine output requested by the driver is obtained. Accordingly, an opening degree control signal is given to the throttle motor 7C for adjusting the opening degree of the throttle valve 7B, the fuel injection amount from an injector (fuel injection valve) (not shown), and the opening / closing timings of the intake and exhaust valves. The ignition timing of the spark plug is controlled.

  Further, during a series of gear change control in the shift change operation of the transmission 3 described above, the rotation of the output shaft 11 of the engine 1 and the input shaft (not shown) of the transmission 3 with the clutch mechanism 2 as a boundary. The output adjustment control of the engine 1 is also performed at the same time so that the number difference is within a preferable range. For this reason, the SMT control unit 6 outputs a required engine output value to the engine control unit 7 so as to provide a suitable engine output in the SMT control during the shift (gear change) control. ing.

  A traction control (TRC) system that suppresses acceleration slip is also mounted, and control processing is executed in a TRC control unit (TRC ECU) 8. The TRC control unit 8 controls the brake actuator 81 that controls the brake pressure of the brake devices 44a and 44a on each wheel based on the difference in wheel rotation speed between the drive wheels 44 and 44 and the driven wheel (not shown). Outputs the hydraulic pressure indication value. At the same time, a required engine output value is obtained so that the engine output is suitable for traction control control, and this required value is output to the engine control unit 7.

  Hereinafter, the configuration of the control system related to the SMT control unit 6 and the engine control unit 7 will be described more specifically with reference to FIG.

  The SMT controller 6 is connected to the clutch actuator 21, shift & select actuator 31, gear position sensor 61, transmission input rotation speed sensor 62, brake lamp switch 63, and shift lever position sensor 64. Detection signals of the sensors 61, 62, and 64 and an engine speed signal from the engine speed sensor 72 are input to the SMT control unit 6, respectively.

  The shift & select actuator 31 includes, for example, an electric motor for shift operation, an electric motor for select operation, reduction gears (bevel gear for shift, rack and pinion for select), shift stroke sensor, select stroke sensor, etc. It is a unit part as a component part. The shift & select actuator 31 performs a shift operation and a select operation via a reduction gear when driven by a motor. Regarding the shift, the shift load is controlled by the motor output.

  The clutch actuator 21 is, for example, a unit component including a clutch operating electric motor, a deceleration worm gear, an assist spring, and a clutch stroke sensor as main components. The clutch actuator 21 performs clutch disconnection and engagement via a reduction gear by driving a motor.

  The shift & select actuator 31 and the clutch actuator 21 are controlled by the SMT controller 6 as described above.

  The engine control unit 7 is connected to an electronic throttle control system 73, an engine 1, an accelerator position sensor 71, an engine speed sensor 72, a throttle opening sensor 74, an engine torque sensor 75, and a display / warning device 76. Detection signals from the sensors 71, 72, 74, and 75 are input to the engine control unit 7, respectively.

  The display device / warning device 76 includes, for example, a gear position indicator and a system warning lamp. The gear position indicator basically displays the gear position of the transmission 3, and also has a function of blinking the gear position of the transmission 3 when a mismatch between the shift lever and the transmission 3 occurs. . Further, the system warning lamp issues a warning to the driver by lighting or blinking the warning lamp when an abnormality occurs in the system.

(Shift load control)
Next, the shift load control operation, which is a characteristic part of the present embodiment, will be described. This shift load control operation is performed for the number of shift changes to be guaranteed for the transmission 3 (hereinafter referred to as the guaranteed number of shifts) when setting the shift load (actual shift load: Fx) obtained from the driving conditions of the vehicle. An upper limit value (allowable shift load: Flim) of the shift load (Fx) for enabling the shift change operation is obtained, and the shift load (Fx) is limited to the allowable shift load (Flim) or less.

  Hereinafter, the shift load control operation will be described with reference to the flowchart of FIG. The routine shown in FIG. 3 is executed every predetermined number of shift changes, for example, every 1000 times. That is, a shift change counter that increments (adds “1”) the count value every time a shift change operation is performed is provided, and this routine is executed every time the count value of the shift change counter reaches “1000”. It is like that. This value can be set arbitrarily.

  First, when a shift change request is generated while the vehicle is running (in the case of the “automatic shift mode”, a shift change request is generated based on a travel condition such as an accelerator opening degree or a vehicle speed. In this case, the actual shift load (Fx) is obtained from various conditions (environmental conditions such as driving conditions of the vehicle and outside temperature) in step ST1. The number of shift changes (Nx) corresponding to the actual shift load (Fx) is calculated. The driving conditions of the automobile include vehicle speed, gear stage information obtained by the shift lever position sensor 64, the opening degree of the accelerator pedal 7A detected by the accelerator position sensor 71, and the engine speed sensor 72. The engine speed is given.

  The actual shift load (Fx) obtained here is a size that enables the slide movement of the synchronizer ring by the shift fork, and the previous allowable shift load (Flim) calculation operation (previously executed in FIG. 3). The value is equal to or less than the allowable shift load (Flim) determined by the routine (this allowable shift load (Flim) calculation operation is as described below). The number of shift changes (Nx) refers to the number of shift changes until the transmission 3 reaches the end of its life when the shifter 3 is performing a shift change operation only with the shift load (Fx) from a new state. It is. As shown in FIG. 4, the number of shift changes (Nx) is inversely proportional to the actual shift load (Fx). The higher the actual shift load (Fx), the lower the number of shift changes (Nx). It will be required.

  Thereafter, in step ST2, the remaining life of the transmission 3 is calculated. The calculation of the remaining life is obtained by the following equation (2) (the remaining life estimation operation by the remaining life estimation means).

Lnew = α (Lold−1 / Nx) (2)
Here, Lnew: the remaining life of the transmission 3 after the shift change operation is performed with the current actual shift load (Fx), α: coefficient, Lold: the shift change operation is performed with the current actual shift load (Fx). Nx: the number of shifts guaranteed when a shift change operation is performed with a shift load (Fx).

  Thereafter, the process proceeds to step ST3, where the cumulative number of shifts (ΣN) is obtained. For example, the total count value of the shift change counter is read.

  In step ST4, the number of shifts (Nlim) corresponding to the remaining life is calculated from the following equation (3). In other words, the number of guaranteed shifts (Nlim) required for the remaining life is calculated.

Nlim = (Nref−ΣN) / Lnew (3)
Here, Nlim: guaranteed number of shifts required for the remaining life, which can be guaranteed when a shift change operation is performed with an allowable shift load (Flim) described later, Nref: shift load during normal driving The number of shifts guaranteed when a shift change operation is performed at (Fref), Fref: standardized shift load in hardware design, and ΣN: cumulative number of shifts.

  Substituting the above equation (2) into equation (3), the following equation (1) is obtained.

α (Lold−1 / Nx) = (Nref−ΣN) / Nlim (1)
By obtaining the number of shifts (Nlim) as described above, an allowable shift load (Flim) corresponding to the number of shifts (Nlim) is obtained in step ST5. That is, the allowable shift load (Flim) can guarantee the number of shifts (Nlim) even if the “shift load” is executed with the allowable shift load (Flim) in all subsequent shift change operations (shift). This value is equivalent to the maximum value of the shift load (the operation for calculating the allowable shift load (Flim) by the allowable shift load calculating means) even if the shift change operation is performed the number of times (Nlim).

  After obtaining the allowable shift load (Flim) in step ST5, in step ST6, it is determined whether or not the obtained allowable shift load (Flim) is larger than the maximum allowable shift load (Fmax). This maximum allowable shift load (Fmax) is the maximum allowable shift load in hardware design of the transmission 3, and when the shift change operation is performed with a shift load having a value exceeding the shift load, the transmission 3 A value that can be corrupted.

  If NO is determined in step ST6 (the allowable shift load (Flim) is determined to be a value equal to or less than the maximum allowable shift load (Fmax)), the allowable shift load (Flim) obtained in step ST5 is determined. Is determined as the current allowable shift load (Flim).

  On the other hand, if YES is determined in step ST6 (the allowable shift load (Flim) is determined to be larger than the maximum allowable shift load (Fmax)), the value of the allowable shift load (Flim) is determined in step ST7. Is replaced with the value of the maximum allowable shift load (Fmax). That is, the allowable shift load (Flim) is limited (limit operation by the shift load limiting means).

  The allowable shift load (Flim) is calculated as described above, and in the next shift load (Fx) calculation operation (shift load calculation operation in step ST1 in the next routine), the upper limit is set by the allowable shift load (Flim). The shift load (Fx) is obtained as a value in which is limited.

  Even when the allowable shift load (Flim) is obtained and the shift load (Fx) is limited as described above, the shift load (Fx) in the shift change operation of the transmission 3 thereafter changes at a low value. In this case, the allowable shift load (Flim) is obtained as a large value. That is, in a situation where a shift change operation with a sudden high shift load is required, a state capable of meeting the demand can be obtained.

  As described above, in the present embodiment, the actual shift load (Fx) is obtained with a value equal to or less than the allowable shift load (Flim) for enabling the guaranteed number of shift changes to be achieved. Fx) allows the shift change operation of the transmission 3 to be executed. That is, when the remaining life (Lnew) is relatively long, the “allowable shift load (Flim)” can be calculated as a relatively high value, and the “shift load” of the shift & select actuator 31 is set high. If the remaining life (Lnew) is relatively short, the “allowable shift load (Flim)” is calculated as a relatively low value, and the “shift load” of the shift & select actuator 31 is limited. become. This avoids the situation where the transmission 3 reaches the end of its life (causes breakage or failure) before reaching the guaranteed number of shift changes regardless of the usage situation and environment of the transmission 3 at the shipping destination. The reliability of the transmission 3 can be ensured.

  Further, in the present embodiment, the “allowable shift load (Flim)” is compared with the “maximum allowable shift load (Fmax)” that is the limit shift load that causes the transmission 3 to be damaged. When (Flim) is calculated as a value higher than “maximum allowable shift load (Fmax)”, “shift load (Fx)” of shift & select actuator 31 is equal to or less than “maximum allowable shift load (Fmax)”. The value is limited. For this reason, the situation in which the transmission 3 reaches the end of its life before reaching the guaranteed number of shift changes is avoided, and the “shift load (Fx)” is too high (the above “maximum allowable shift load ( Fmax) ”can be avoided, and the transmission 3 can be damaged. That is, according to the present embodiment, it is possible to guarantee the operation of the transmission 3 from both the strength side of the transmission 3 and the lifetime of fatigue.

-Other embodiments-
In the embodiment described above, the case where the present invention is applied to the transmission 3 mounted in the FR (front engine / rear drive) type automobile has been described. The present invention is not limited to this, and can also be applied to a transmission mounted in an FF (front engine / front drive) type automobile or a transmission installed in a midship type automobile.

  In the above-described embodiment, the allowable shift load (Flim) is calculated every predetermined number of shift changes. However, the allowable shift is performed every shift change (every time one shift change operation is completed). You may make it perform the calculation operation | movement of a load (Flim).

  Further, in the above-described embodiment, the number of guaranteed shifts (for example, 500,000 times) is set in advance as the life of the transmission 3, and the allowance for securing the remaining guaranteed number of times by subtracting the cumulative number of shifts from this guaranteed number of shifts. The shift load (Flim) was calculated. The present invention is not limited to this, and as the lifetime of each part constituting the transmission 3, the guaranteed number of operations is set in advance, and the remaining number of operations is ensured by subtracting the cumulative number of operations from the number of guaranteed operations. The allowable shift load (Flim) may be calculated.

  Further, in the above embodiment, the “F / N diagram” for obtaining the relationship between the “shift load (F)” and the number of shifts (N) guaranteed when the shift change operation is performed with the “shift load”. From this, the remaining life of the transmission 3 was estimated. Instead, a relational expression between the shift load and the number of shifts may be obtained experimentally, and the remaining life of the transmission 3 may be estimated based on this relational expression.

  In addition, in the above-described embodiment, the case where the present invention is applied to a two-pedal type vehicle that does not include a clutch pedal has been described. It is applicable also to what is called a clutch-by-wire type which operates.

It is a figure which shows schematic structure of the powertrain and control system of the motor vehicle which concern on embodiment. It is a block diagram which shows the structure of the control system relevant to a SMT control part and an engine control part. It is a flowchart figure which shows the procedure of shift load control operation | movement. It is a figure which shows the relationship between a shift load and the frequency | count of a shift.

Explanation of symbols

1 Engine (drive source)
3 Transmission 31 Shift & Select Actuator 44 Drive Wheel (Wheel)
6 SMT controller

Claims (6)

A shift change operation that changes the gear that transmits power from the drive source to the wheels by the operation of the shift operation unit by this "shift load" that can be changed from the actuator to the shift operation unit In a shift control device for a transmission that executes
A remaining life estimation means for estimating the remaining life of the transmission from the "shift load" in the shift change operation executed in the past and the cumulative value of the number of shifts;
And an allowable shift load calculating means for calculating an “allowable shift load” that is an upper limit regulation value of the “shift load” based on the remaining life of the transmission estimated by the remaining life estimation means. A shift control device for a transmission. A shift change operation that changes the gear that transmits power from the drive source to the wheels by the operation of the shift operation unit by this "shift load" that can be changed from the actuator to the shift operation unit In a shift control device for a transmission that executes
The following formula (1),
α (Lold−1 / Nx) = (Nref−ΣN) / Nlim (1)
(Α: coefficient, Lold: remaining life of transmission at end of previous shift change operation, Nx: number of shifts guaranteed when shift change operation is performed with shift load (Fx) (shift load (Fx) is The actual shift load when the shift change operation is executed), Nref: the number of shifts guaranteed when the shift change operation is performed with the shift load (Fref) during normal driving (the shift load (Fref) is determined by hardware design) Standardized shift load), ΣN: cumulative shift count, Nlim: guaranteed shift count required for remaining life)
A shift control apparatus for a transmission, comprising: an allowable shift load calculating means for calculating an allowable shift load (Flim) corresponding to the number of shifts (Nlim). In the shift control device for a transmission according to claim 1 or 2,
The “allowable shift load” calculated by the allowable shift load calculating means is compared with the “maximum allowable shift load” which is the limit shift load that causes the transmission to break. And a shift load limiting means for limiting the “shift load” of the actuator to a value equal to or less than the “maximum allowable shift load” when calculated as a value higher than “”. . In the shift control device for a transmission according to claim 1, 2, or 3,
The shift control device for a transmission is characterized in that the allowable shift load calculation means is configured to execute a calculation operation of “allowable shift load” every predetermined number of shift changes. In the shift control device for a transmission according to claim 1, 2, or 3,
The shift control device for a transmission is characterized in that the allowable shift load calculating means is configured to execute an operation of calculating an “allowable shift load” every time a shift change operation is performed. In the shift control device for a transmission according to any one of claims 1 to 5,
The remaining life estimation means obtains the relationship between the “shift load (F)” and the number of shifts (N) guaranteed when the shift change operation is continuously performed with the “shift load”. A shift control apparatus for a transmission, characterized in that the remaining life of the transmission is estimated from the figure.

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