JP2010175058A - Speed change control device of automatic transmission for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure the variable speed line following performance for the gear change ratio at the time of a regular gear change and the fixed gear change ratio setup while restricting the inertia torque generated on a transmission input shaft during speed change transition. <P>SOLUTION: The upper and the lower limit values (S1-S4, S6-S8) of a target input numbers of rotation variation are set up from the throttle opening degree on the pressing amount of the vehicle accelerator pedal, the basic target input number of rotation which is set up from the vehicle speed and the actual output numbers of rotation etc. as the target change ratio after last correction. The upper and the lower limit values (S5, S9) of variation of the target gear change ratio are calculated from the target input numbers of rotation variation and the basic target change gear rate is made to be the target change gear ratio after correction when the change gear ratio deviation from the basic target change gear ratio to the one after last correction does not exceed the upper and the lower limit value of the target gear variation. When exceeded, the upper and the lower limit values of the target change gear ratio are added to the last target change gear ratio after correction so as to set a target change gear ratio after correction, which is output (S10), thus controlling the gear change ratio of the automatic transmission for the vehicle based on the target gear change ratio after correction, in the speed change control device of the automatic transmission for vehicle. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a speed change control device for controlling the speed ratio of an automatic transmission for a vehicle that shifts an input rotation from a drive source of a vehicle and outputs the speed to drive wheels and automatically changes the speed ratio. In this specification, unless otherwise specified, “rotational speed” means “rotational speed per unit time”, that is, “rotational speed”.

  Conventionally, for example, as a shift control device for a belt-type continuously variable transmission as an automatic transmission for a vehicle, the basic target engine speed determined according to the throttle opening based on the accelerator pedal depression amount and the vehicle speed is regulated. It is known that the rear target engine speed is obtained and the gear ratio is controlled so that the actual engine speed coincides with the post-regulation target engine speed. In this speed change control apparatus, the accelerator pedal is controlled by restricting the amount of change (rate of change) per unit time of the basic target engine speed by a restriction value set in consideration of the actual speed ratio of the continuously variable transmission. Shift control reflecting the driving operation of the driver and the running state of the vehicle is realized while suppressing the occurrence of pulling shock and shift delay due to the inertia torque generated on the transmission input shaft during sudden depression. Patent Document 1).

JP-A-8-326858

  However, in the conventional transmission control device for a continuously variable transmission as described above, the rate of change of the basic target engine speed is regulated by a regulation value corresponding to the actual gear ratio that depends on the throttle opening and the vehicle speed. Since the target engine speed after regulation is only controlled, the inertia torque of the rotating element can be limited, but the automatic upshift or accelerator pedal is released during steady shift, that is, while maintaining the accelerator pedal depression amount. If the above restriction is applied in a situation where the input rotational speed is increased with a change in vehicle speed such as automatic downshift during coasting, the post-regulation target engine speed (target gear ratio) will be the throttle opening and the vehicle speed. Accordingly, there is a problem in that it does not follow the pre-regulation target engine speed (target gear ratio) determined by the shift line.

  In particular, when a transmission line with a constant gear ratio is set, if the rate of change in the engine speed accompanying the change in vehicle speed at that speed ratio, that is, the input speed of the continuously variable transmission is too large, the post-regulation target engine speed In other words, in order to realize the target input rotation speed, there is a problem that the gear ratio cannot be kept constant in spite of the above setting, and an upshift or a downshift occurs.

  Therefore, the present inventor who studied this problem, the transmission input rotational speed Inprev at the change rate d (Inprev) / dt of the transmission input rotational speed is the product Ratio × Outrev of the transmission ratio and the transmission output rotational speed. Yes, since the derivative of the product of the two variables is expressed as the sum of the derivatives of the variables, the change rate of the transmission input speed d (Inprev) / dt = d (Ratio × Outrev) / dt = d (Ratio) It was found that / dt × Outrev + Ratio × d (Outrev) / dt, and the second term on the rightmost side of this equation is an input rotational speed change rate increase term accompanying a change in vehicle speed.

  If the overall change rate d (Inprev) / dt of the transmission input speed is restricted in order to prevent a pulling shock due to inertia torque generated in the transmission input shaft due to a transitional speed ratio change, The amount of change in the input rotation speed change rate in the second term on the rightmost side of the equation is also restricted, and the followability of the post-regulation target input rotation speed with respect to the pre-regulation target input rotation speed deteriorates, and the change in the target input rotation speed If it is necessary to change the gear ratio, the steady driving force requirement is set by the gear line, and only the inertia torque generated on the transmission input shaft due to the transient gear ratio change is limited. I came up with the idea that the problem could be solved. Therefore, the present invention restricts the change in the input rotational speed Inprev accompanying the change in the transmission ratio Ratio (the first term on the rightmost side of the above-mentioned equation for the change rate of the transmission input rotational speed) while changing the transmission ratio Ratio. The problem of the prior art is advantageous by not restricting the change in the input rotational speed Inprev (the second term on the rightmost side of the transmission input rotational speed change equation) associated with the change in the vehicle speed Vsp regardless of the vehicle speed It will be solved.

  According to a first aspect of the shift control device for an automatic transmission for a vehicle according to the present invention, the basic target input rotation speed set from the throttle opening and the vehicle speed, and the actual output rotation speed are set to the immediately preceding corrected target gear ratio. The upper and lower limits of the target input speed change rate are set based on the input speed multiplied and the speed deviation, and the target speed ratio is calculated by dividing the upper and lower limits of the target input speed change rate by the actual output speed. The upper and lower limit values of the rate of change are obtained, the gear ratio deviation between the basic target speed ratio obtained by dividing the basic target input speed by the actual output speed and the corrected target speed ratio immediately before, and the upper and lower limits of the target speed ratio change rate If the gear ratio deviation does not exceed the upper and lower limits of the target gear ratio change rate, the basic target gear ratio is output as the corrected target gear ratio, and the gear ratio deviation is the upper and lower limits of the target gear ratio change rate. If the value exceeds the value, the upper and lower limit values of the target gear ratio change rate are added to the target gear ratio after correction. Ete output as the corrected target gear ratio, and controls on the basis of the gear ratio of the automatic transmission for a vehicle to the corrected target transmission ratio.

  According to a second aspect of the present invention, there is provided a shift control apparatus for an automatic transmission for a vehicle, wherein, in the second aspect, a basic target speed ratio obtained by dividing a basic target input rotational speed set from a throttle opening and a vehicle speed by an actual output rotational speed; The upper and lower limits of the target gear ratio change rate are set based on the gear ratio deviation from the immediately preceding corrected target gear ratio, and the gear ratio deviation is compared with the upper and lower limits of the target gear ratio change rate. If the target gear ratio change rate does not exceed the upper and lower limits, the basic target gear ratio is output as the corrected target gear ratio. If the gear ratio deviation exceeds the upper and lower limits of the target gear ratio change rate, An upper and lower limit value of the target speed ratio change rate is added to the target speed ratio and output as a corrected target speed ratio, and the speed ratio of the vehicle automatic transmission is controlled based on the corrected target speed ratio.

  Furthermore, in the third aspect of the shift control apparatus for an automatic transmission for a vehicle according to the present invention, in the third aspect, the actual target output speed is set to the basic target input speed set from the throttle opening and the vehicle speed, and the immediately preceding corrected target speed ratio. The upper and lower limits of the target input speed change rate are set based on the input speed and the deviation of the input speed, and the upper and lower limits of the target input speed change rate and the target input speed change after the previous limit are set. The upper and lower limits of the target input speed change rate are compared with the upper and lower limits of the target input speed change rate. If not, the upper and lower limits of the target input speed change rate are output as the upper and lower limits of the target input speed change rate after the limit. The upper and lower limits of the target input speed change rate are the upper and lower limits of the target input speed change rate. If this value is exceeded, the upper and lower limits of the target input speed change rate limit will be controlled. The target input speed change rate upper / lower limit value is output, and the target input speed change rate upper / lower limit value is divided by the actual output speed to obtain the upper / lower limit value of the target gear ratio change rate. The gear ratio deviation is determined by comparing the gear ratio deviation between the basic target gear ratio obtained by dividing the speed by the actual output speed and the immediately preceding corrected target gear ratio and the upper and lower limits of the target gear ratio change rate. If the upper / lower limit value of the ratio change rate is not exceeded, the basic target gear ratio is output as the corrected target gear ratio, and if the gear ratio deviation exceeds the upper / lower limit value of the target gear ratio change rate, the target speed ratio is set to the previous target speed ratio. The upper and lower limits of the speed ratio change rate are added and output as a corrected target speed ratio, and the speed ratio of the vehicle automatic transmission is controlled based on the corrected target speed ratio.

  According to a fourth aspect of the present invention, there is provided a shift control device for a vehicle automatic transmission according to the fourth aspect, wherein a basic target gear ratio obtained by dividing a basic target input rotational speed set from a throttle opening and a vehicle speed by an actual output rotational speed The upper and lower limit values of the target gear ratio change rate are set based on the gear ratio deviation from the corrected target gear ratio, and the upper and lower limit values of the target gear ratio change rate and the immediately preceding limited target gear ratio change rate upper and lower limit values are set. If the upper and lower limit values of the target gear ratio change rate do not exceed the upper and lower limit values of the target gear ratio change rate, the target gear ratio The upper / lower limit value of the change rate is output as the upper / lower limit value of the target gear ratio change rate after restriction. If the upper / lower limit value of the target gear ratio change rate exceeds the upper / lower limit value of the target gear ratio change rate, the target gear ratio change rate The limit upper / lower limit value is output as the upper / lower limit value of the target gear ratio change rate after the limit. The gear ratio deviation is compared with the upper / lower limit value of the target gear ratio change rate after restriction. If the gear ratio deviation does not exceed the upper / lower limit value of the target gear ratio change rate after restriction, the basic gear ratio is corrected and the target gear ratio is corrected. If the gear ratio deviation exceeds the upper / lower limit value of the target gear ratio change rate after restriction, the upper / lower limit value of the target gear ratio change rate after restriction is added to the previous target gear ratio and output as the corrected target gear ratio. The speed ratio of the vehicle automatic transmission is controlled based on the corrected target speed ratio.

  According to the first aspect of the shift control device for an automatic transmission for a vehicle of the present invention, the target input rotation speed change rate is set as the target gear ratio change rate x the transmission actual output rotation speed, and the upper and lower limit values are provided. Therefore, since only the target gear ratio change rate is regulated to obtain the corrected target gear ratio, the inertia torque generated on the transmission input shaft during the shift transition is limited, while the accelerator pedal depressing amount is being maintained. It is possible to ensure the shift ratio followability of the gear ratio at the time of steady gear shift such as automatic upshift or automatic downshift during coasting with the accelerator pedal released, or at a fixed gear ratio setting.

  According to the second aspect of the shift control device for an automatic transmission for a vehicle according to the present invention, the corrected target is obtained by directly setting the upper and lower limit values for the target speed ratio change rate and restricting only the target speed ratio change rate. Since the gear ratio is calculated, the inertia torque generated on the transmission input shaft during the shift transition is limited, while the automatic upshift while driving the accelerator pedal and the automatic down during coasting driving when the accelerator pedal is released It is possible to ensure the shift line followability of the speed ratio at the time of a steady speed change such as a shift or when the speed ratio is fixed.

  Furthermore, according to a third aspect of the shift control apparatus for an automatic transmission for a vehicle of the present invention, in the first aspect, a change in the target speed ratio change rate is provided by providing a limit upper and lower limit value for the target input rotation speed change rate. Since the speed is regulated, the slope of the change over time of the inertia torque at the shift transition is limited, while the automatic upshift while driving with the accelerator pedal depressed and the automatic downshift while coasting with the accelerator pedal released It is possible to ensure the shift line followability of the speed ratio at the time of the steady speed shift or the fixed speed ratio setting.

  According to the fourth aspect of the shift control apparatus for an automatic transmission for a vehicle of the present invention, in the second aspect, the change speed of the target speed ratio change rate is set by providing a limit upper / lower limit value for the target speed ratio change rate. Therefore, while limiting the slope of inertia change over time during shift transitions, automatic upshifting while maintaining the accelerator pedal depression amount, automatic downshifting during coasting with the accelerator pedal released, etc. It is possible to ensure the shift line followability of the speed ratio at the time of steady speed change or speed ratio fixed setting.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view showing a system configuration of an automobile equipped with a shift control device for a vehicle belt type continuously variable transmission as each embodiment of a shift control device for an automatic transmission for a vehicle according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram functionally showing the configuration of a first embodiment of a shift control apparatus for a vehicle automatic transmission according to the present invention. It is a graph which shows each time change of each factor of a car using the gear shift control device of the 1st embodiment at the time of depressing an accelerator pedal suddenly. It is a graph which respectively shows the time change of the torque of the motor vehicle using the transmission control apparatus concerning the prior art at the time of stepping on an accelerator pedal. It is a graph which each shows the time change of each factor of the motor vehicle using the transmission control apparatus concerning the prior art at the time of stepping on an accelerator pedal. It is a block diagram which shows functionally the structure of 2nd Embodiment of the transmission control apparatus of the automatic transmission for vehicles of this invention. It is a block diagram which shows functionally the structure of 3rd Embodiment of the shift control apparatus of the automatic transmission for vehicles of this invention. It is a graph which shows each time change of each factor of a car using the shift control device of the 3rd embodiment at the time of depressing an accelerator pedal suddenly. It is a block diagram which shows functionally the structure of 3rd Embodiment of the shift control apparatus of the automatic transmission for vehicles of this invention.

  Hereinafter, four embodiments of a shift control device for an automatic transmission for a vehicle according to the present invention will be described in detail with reference to the drawings. FIG. 1 is an explanatory diagram showing a system configuration of an automobile equipped with a shift control device for a belt type continuously variable transmission for a vehicle as each embodiment of a shift control device for an automatic transmission for a vehicle according to the present invention. Fig. 3 is a block diagram functionally showing the configuration of the speed change control device of the first embodiment of the present invention, and Fig. 3 is a diagram of an automobile using the speed change control device of the first embodiment when the accelerator pedal is suddenly depressed. It is a graph which shows the time change of each factor, respectively.

  As shown in FIG. 1, an automobile 1 as a vehicle to which a shift control apparatus according to an embodiment of the present invention is applied includes an engine 2 as a drive source, an input pulley (not shown), and an output pulley (not shown). A belt-type continuously variable transmission 3 that continuously changes the gear ratio by relatively increasing or decreasing the radius of rotation of a belt (not shown) wound around the belt, and the output of the engine 2 and the belt-type continuously variable The input shaft coupled to the input pulley of the transmission 3 is connected by a torque converter 4 with a lock-up clutch. The engine rotation input from the engine 2 to the input pulley via the torque converter 4 is shifted according to the gear ratio, and the vehicle 1 is driven from the output shaft coupled to the output pulley via a differential gear (not shown). The power is output to the tire 5 as a wheel, and the tire 5 is driven.

  Here, the operation of the engine 2 is controlled by an engine control unit 6 via a throttle valve (not shown). The engine control unit 6 uses the throttle opening TVO, which is the opening of the throttle valve, as a basis. Specifically, it is changed in accordance with an accelerator pedal opening APO that is an operation amount of an accelerator pedal of the automobile 1 detected by a sensor (not shown). The belt-type continuously variable transmission 3 as an automatic transmission for a vehicle is controlled by a transmission control device 7 as a transmission control device. The transmission control device 7 has, for example, a normal microcomputer. In addition to the engine torque and engine speed input from the engine control unit 6, the accelerator opening APO detected by a sensor (not shown), the vehicle speed VSP of the automobile 1, and the input speed of the belt type continuously variable transmission 3 Shift control is performed as follows based on information such as Inprev.

  That is, the microcomputer of the transmission control device 7 repeatedly executes the process shown in FIG. 2 every predetermined cycle time. In this process, first, the multiplier S1 performs correction described later as the immediately previous corrected target gear ratio. Multiplying the previous value of the rear target gear ratio vTGTRTO0 (the value obtained in the previous processing) by the actual output speed Outrev of the belt-type continuously variable transmission 3 obtained from the vehicle speed VSP, obtains the actual input speed of the transmission. . Separately, from the normal shift map (not shown) in which the shift line is determined based on the throttle opening TVO and the vehicle speed VSP determined based on the accelerator pedal opening APO, the current vehicle speed VSP and the accelerator read earlier. The basic target input rotational speed DsrREV is obtained according to the pedal opening APO. Subsequently, the subtractor S2 obtains a rotation speed deviation (rotational speed change rate) erev between the basic target input rotation speed DsrREV and the transmission actual input rotation speed.

  Next, the basic upper limit of the target input rotational speed change rate drev (that is, {d (Ratio) / dt} × Outrev) based on the top characteristic diagram in the characteristic group S3 from the rotational speed deviation erev. Find the value. For example, when the rotational speed deviation erev is equal to or less than a predetermined value, the basic upper limit value of the target input rotational speed change rate drev increases as the rotational speed deviation erev exceeds a predetermined value. The basic upper limit value of the target input rotational speed change rate drev is set to be constant, and the basic upper limit value of the target input rotational speed change rate drev is set higher as the vehicle speed VSP is higher. Further, the coefficient α1 is obtained from the second map from the top in the characteristic group S3. In this map, the coefficient α1 is determined according to the current shift position SftPOS and the previous shift position BefPOS. The larger the gear ratio, the greater the influence on the inertia torque. The basic upper limit value of the rotational speed change rate drev is regulated. For example, when downshifting from the manual shift position M3 to M2, the coefficient α1 is read as the current shift position BefPOS = M3 and the current shift position SftPOS = M2. Further, the coefficient α2 is obtained from the third characteristic diagram from the top in the characteristic group S3. In this characteristic diagram, the coefficient α2 is set in accordance with the speed change mode and the engine torque TENG. When the engine torque is sufficiently high, the coefficient α2 is set to be large and the basic of the target input rotational speed change rate drev is set. The upper limit is not so restricted.

  Next, the multiplier S4 multiplies the basic upper limit value of the target input speed change rate drev by the coefficients α1 and α2 to obtain the target input speed change rate {d (Ratio) / dt} × Outrev upper limit value, and then In the divider S5, the target input speed change rate {d (Ratio) / dt} × Outrev upper limit value is divided by the transmission actual output speed Outrev to obtain the target gear ratio change rate d (Ratio) / dt upper limit value. Ask.

  On the other hand, the subtractor S6 obtains the rotational speed deviation erev between the basic target input rotational speed DsrREV and the transmission actual input rotational speed in the same manner as the subtractor S2, and then from the rotational speed deviation erev by the characteristic group S7. In the same manner as in the characteristic group S3, the basic lower limit value and the coefficients α3 and α4 of the target input rotational speed change rate drev (that is, {d (Ratio) / dt} × Outrev) are obtained. Next, the multiplier S8 multiplies the basic lower limit value of the target input speed change rate drev by the coefficients α3 and α4, respectively, to obtain the lower limit value of the target input speed change rate {d (Ratio) / dt} × Outrev. Next, in the divider S9, the target input speed change rate {d (Ratio) / dt} × Outrev lower limit value is divided by the output speed Outrev to obtain the target gear ratio change rate d (Ratio) / dt lower limit value. In this way, the upper and lower limit values of the target input rotational speed change rate and the upper and lower limit values of the target gear ratio change rate are obtained.

  Further, the basic target input rotational speed DsrREV is divided by the transmission actual output rotational speed Outrev, and the upper and lower limit values of the target speed ratio change rate d (Ratio) / dt are calculated by the calculator. In S10, the corrected target speed ratio vTGTRTO0, which is the speed ratio after limiting the target speed ratio change rate d (Ratio) / dt, is calculated. Here, the arithmetic unit S10 sets the speed ratio deviation (speed change rate of speed ratio) between the basic target speed ratio and the previous value of the corrected target speed ratio vTGTRTO0, and the upper and lower limits of the target speed ratio change rate d (Ratio) / dt. If the gear ratio deviation is between the upper limit value and lower limit value of the target gear ratio change rate d (Ratio) / dt, the current value of the target gear ratio vTGTRTO0 after correcting the basic target gear ratio. If the gear ratio deviation is outside the range between the upper limit and lower limit of the corrected target gear ratio change rate d (Ratio) / dt, it is corrected to the previous value of the corrected target gear ratio vTGTRTO0. A value obtained by adding the side closer to the gear ratio deviation among the upper limit value and the lower limit value of the target gear ratio change rate d (Ratio) / dt is output as the current value of the corrected target gear ratio vTGTRTO0.

  Then, the current value of the corrected target gear ratio vTGTRTO0 is inputted to and held in the holding (delay) unit (1 / z) S11 and is given as the previous value to the multiplier S1 in the next processing, and the corrected target gear ratio is also obtained. The current value of vTGTRTO0 is output to the belt-type continuously variable transmission 3, and the gear ratio of the belt-type continuously variable transmission 3 is changed so as to realize the current value of the corrected target gear ratio vTGTRTO0.

  The time change of each factor when the shift control at the time of sudden depression of the accelerator pedal is performed by the transmission control device 7 of the first embodiment and only d (Ratio) / dt × Outrev is limited is shown in FIG. become. Here, FIG. 4 showing the prior art in which the speed change control at the time of sudden depression of the accelerator pedal is performed with a gear ratio command value of the first order delay, and the speed change control at the time of sudden depression of the accelerator pedal is performed by the deviation of the actual input speed from the target input speed In comparison with FIG. 5 showing the prior art performed by the limitation, in the first embodiment, after the accelerator pedal is suddenly depressed (accelerator pedal opening APO step-like increase), the vehicle speed is increased and the transmission output rotation is increased. Outrev increases, and the basic target input speed DsrREV also increases as the vehicle speed VSP in the shift map increases. At this time, if the change in the throttle opening TVO does not cross the shift line, it rises gently as shown by the solid line, and if the change in the throttle opening TVO crosses the shift line, it rises gently as shown by the broken line once. To rise. If the rate of change of the basic target input speed DsrREV during this gentle increase is 700 rpm / sec, for example, while the target d (Ratio) / dt × Outrev upper limit value is 500 rpm / sec, the basic The rate of change (slope) of the target input speed DsrREV, that is, the slope of the actual input speed Inprev is not restricted and is maintained at 700 rpm / sec as shown by the solid line, and only the increase due to the shift is shown as 500 rpm / It is restricted not to rise beyond sec. Therefore, since the increase in the actual input speed Inprev according to the increase in the actual output speed Outrev is not limited in the actual input speed Inprev / the actual output speed Outrev of the transmission, it is indicated by a broken line when changing the gear ratio. Thus, it is possible to ensure followability of the shift map to the shift line. In addition, when the gear ratio is fixed as instructed by the gear ratio control device 7 by operating a shift lever (not shown) to the manual gear shift mode, the basic upper and lower limit values of the target input rotation speed change rate drev are set to zero. As shown by the solid line, the gear ratio Ratio can be kept constant.

  Accordingly, the multipliers S1, S4, S8, the subtractors S2, S6, the characteristic groups S3, S7 and the retainer S11 correspond to the target input rotational speed change rate upper / lower limit value setting means, and the dividers S5, S9 are the target Corresponding to the gear ratio change rate upper / lower limit setting means, the calculator S10 corresponds to the corrected target gear ratio output means, and the transmission control device 7 corresponds to the gear ratio control means. According to the transmission control device 7 of the first embodiment, the change in the input rotation speed Inprev accompanying the change in the transmission gear ratio Ratio (the first term on the rightmost side of the equation for the change rate of the transmission input rotation speed). However, there is no restriction on the change of the input speed Inprev accompanying the change of the vehicle speed Vsp regardless of the change of the gear ratio Ratio (the second term on the rightmost side of the equation of the change rate of the input speed of the transmission). For example, when the gear ratio Ratio changes due to the throttle opening / closing operation by depressing or returning the accelerator pedal, the change in the input rotation speed Inprev is limited. For example, the throttle opening / closing at a fixed gear ratio in the manual mode When the input rotation speed Inprev changes so as to keep the speed ratio constant by operation, the change is not limited. This restricts inertia torque generated on the transmission input shaft during shift transitions, while maintaining steady shifts such as automatic upshifts during travel while maintaining the accelerator pedal depression amount and automatic downshifts during coasting when the accelerator pedal is released. When the gear ratio is fixed or when the gear ratio is fixed, it is possible to ensure the shift line followability of the gear ratio.

On the other hand, in the prior art shown in FIG. 4, when the accelerator pedal is suddenly depressed (accelerator pedal opening APO step-like increase), the target gear ratio Ratio changes abruptly as shown by the solid line, and a primary delay gear ratio command is provided. Although the gear ratio is controlled by outputting a value, the gradient of the gear ratio Ratio is maximized immediately after sudden depression of the accelerator pedal, whereas the engine torque Te rises slightly later due to a delay in intake, so the inertia of the transmission input shaft The torque T _INA is greatly reduced, and the driving torque (drive shaft torque) D / SftTRQ (= (Te + T _INA ) × Ratio) during the shift is less than zero, and the vehicle acceleration is pulled.

  In the prior art shown in FIG. 5, after the accelerator pedal is suddenly depressed (accelerator pedal opening APO step-like increase), the vehicle speed increases and the transmission output rotation Outrev increases, resulting in an increase in the vehicle speed VSP in the shift map. Accordingly, the basic target input speed DsrREV also increases. At this time, if the change in the throttle opening TVO does not straddle the shift line, it gradually increases as shown by the solid line. If the rate of change of the basic target input speed DsrREV during this gentle rise is 700 rpm / sec, for example, while the transmission actual input speed d (Inprev) / dt upper limit is 500 rpm / sec, the vehicle speed As shown in the broken line, the change rate (slope) of the basic target input speed DsrREV due to the rise is limited to 500 rpm / sec, even if the actual input speed Inprev is 700 rpm / sec. The target input speed DsrREV cannot keep up. Accordingly, since the increase in the actual input rotation speed Inprev cannot catch up with the increase in the actual output rotation speed Outrev at the actual input rotation speed Inprev / the actual output rotation speed Outrev of the transmission, the transmission gear ratio is automatically upshifted. For this reason, it is not possible to ensure the shift line followability of the speed ratio at the time of a steady speed change or a speed ratio fixed setting.

  FIG. 6 is a block diagram functionally showing the configuration of the shift control apparatus of the second embodiment of the present invention. In the first embodiment, the upper and lower limit values of the target input speed change rate drev (that is, {d (Ratio) / dt} × Outrev) are obtained once, and from there, the target speed ratio change rate d (Ratio) / dt is increased. Although the lower limit value has been obtained, in the second embodiment, the upper and lower limit values of the target gear ratio change rate d (Ratio) / dt are obtained directly.

  Specifically, the basic target input speed DsrREV is first divided by the actual output speed Outrev in the divider S21 to obtain the basic target speed ratio, and then the subtractor S22 calculates the immediately preceding target speed ratio from the basic target speed ratio. Subtracting a previous value (a value obtained in the previous process) of a corrected target gear ratio vTGTRTO0, which will be described later, as a corrected target gear ratio, obtains a gear ratio deviation (speed change rate of the gear ratio with time) eip.

  Next, from the speed ratio deviation eip, the target speed ratio change rate d is first determined from the characteristic group S23 in the same manner as in the characteristic group S3 in the first embodiment, based on the uppermost characteristic diagram in the characteristic group S23. Calculate the basic upper limit of (Ratio) / dt. Further, the coefficient β1 is obtained from the second map from the top in the characteristic group S23. Further, the coefficient β2 is obtained from the third characteristic diagram from the top in the characteristic group S23. These characteristics are determined in the same manner as the characteristic group S3, for example.

  Next, the multiplier S24 multiplies the basic upper limit value of the target gear ratio change rate d (Ratio) / dt by coefficients β1 and β2, respectively, to obtain the target gear ratio change rate d (Ratio) / dt upper limit value.

  On the other hand, the subtractor S25 subtracts the previous value (the value obtained in the previous processing) of the corrected target gear ratio vTGTRTO0 from the basic target gear ratio in the same manner as the subtractor S22 to obtain the gear ratio deviation eip. The basic lower limit value and the coefficients β3 and β4 of the target gear ratio change rate d (Ratio) / dt are obtained from the gear ratio deviation eip by the characteristic group S26 in the same manner as in the characteristic group S23. Next, the multiplier S27 multiplies the basic lower limit value of the target gear ratio change rate d (Ratio) / dt by coefficients β3 and β4, respectively, to obtain the lower limit value of the target gear ratio change rate d (Ratio) / dt. In this way, the upper and lower limit values of the target gear ratio change rate are obtained.

  Further, the basic target input rotational speed DsrREV is divided by the transmission actual output rotational speed Outrev, and the upper and lower limit values of the target speed ratio change rate d (Ratio) / dt are calculated by the calculator. In S28, the corrected target gear ratio vTGTRTO0, which is the speed ratio after limiting the change in the target gear ratio change rate d (Ratio) / dt, is calculated. Here, as with the calculator S10 in the first embodiment, the calculator S28 is a gear ratio deviation (change rate of the gear ratio per unit time) between the basic target gear ratio and the previous value of the corrected target gear ratio vTGTRTO0. Is compared with the upper and lower limit values of the target gear ratio change rate d (Ratio) / dt, and the gear ratio deviation is between the upper limit value and lower limit value of the target gear ratio change rate d (Ratio) / dt. When the basic target gear ratio is output as the current value of the corrected target gear ratio vTGTRTO0, and the gear ratio deviation is outside the range between the upper limit and lower limit of the target gear ratio change rate d (Ratio) / dt Is the value obtained by adding the value close to the gear ratio deviation between the upper limit and lower limit of the corrected target gear ratio change rate d (Ratio) / dt to the previous value of the corrected target gear ratio vTGTRTO0. Output as current value of ratio vTGTRTO0.

  Then, the current value of the corrected target gear ratio vTGTRTO0 is input to and held in the holding (delay) unit (1 / z) S29 and is given as the previous value to the subtracters S22 and S25 in the next processing, and the corrected target The current value of the gear ratio vTGTRTO0 is output to the belt type continuously variable transmission 3, and the speed ratio of the belt type continuously variable transmission 3 is changed so as to realize the current value of the corrected target speed ratio vTGTRTO0.

  Accordingly, the divider S21, the subtracters S22 and S25, the characteristic groups S23 and S26, the multipliers S24 and S27, and the holder S29 correspond to the target gear ratio change rate upper / lower limit value setting means, and the calculator S28 is the corrected one. It corresponds to the target gear ratio output means, and the transmission control device 7 corresponds to the gear ratio control means. Also in the transmission control device 7 of the second embodiment, as in the first embodiment, the change in the input rotation speed Inprev accompanying the change in the transmission gear ratio Ratio (the expression for the change rate of the transmission input rotation speed) The first term on the rightmost side of the engine), while the input speed Inprev changes with the change in the vehicle speed Vsp regardless of the change in the gear ratio Ratio (the rightmost side of the equation for the change rate of the input speed of the transmission). No restriction is imposed on the second term). For example, when a change in the gear ratio Ratio occurs due to a throttle opening / closing operation by depressing or depressing the accelerator pedal, the change in the input rotational speed Inprev is limited. When the input rotational speed Inprev changes so as to keep the transmission gear ratio constant by the throttle opening / closing operation with the gear ratio fixed, the change is not limited. This restricts inertia torque generated on the transmission input shaft during shift transitions, while maintaining steady shifts such as automatic upshifts during travel while maintaining the accelerator pedal depression amount and automatic downshifts during coasting when the accelerator pedal is released. When the gear ratio is fixed or when the gear ratio is fixed, it is possible to ensure the shift line followability of the gear ratio.

  FIG. 7 is a block diagram functionally showing the configuration of the shift control apparatus according to the third embodiment of the present invention. In the first embodiment, the upper and lower limit values of the target input speed change rate drev (that is, {d (Ratio) / dt} × Outrev) are obtained, and the target speed ratio change rate d (Ratio) / dt is directly calculated therefrom. Although the upper and lower limit values have been obtained, in the third embodiment, the change rate (that is, the slope) of the upper and lower limit values of the target input rotational speed change rate drev (ie, {d (Ratio) / dt} × Outrev) is limited, The upper and lower limit values of the target gear ratio change rate d (Ratio) / dt are obtained from the upper and lower limit values of the target input rotational speed change rate after the limitation.

  Specifically, first, the multiplier S31 uses a belt type obtained from a previous value (a value obtained in the previous processing) of a corrected target speed ratio vTGTRTO0, which will be described later, as a previous corrected target speed ratio, and a vehicle speed VSP. The actual output rotational speed Outrev of the continuously variable transmission 3 is multiplied to obtain the actual transmission rotational speed. Separately, from the normal shift map (not shown) in which the shift line is determined based on the throttle opening TVO and the vehicle speed VSP determined based on the accelerator pedal opening APO, the current vehicle speed VSP and the accelerator read earlier. The basic target input rotational speed DsrREV is obtained according to the pedal opening APO. Subsequently, a subtracter S32 obtains a rotation speed deviation (rotational speed change rate) erev between the basic target input rotation speed DsrREV and the transmission actual input rotation speed.

  Next, from the rotational speed deviation erev, the characteristic group S33 is used, as in the characteristic group S3 in the first embodiment, first, based on the uppermost characteristic diagram in the characteristic group S33, the target input rotational speed change rate drev. The basic upper limit value (that is, {d (Ratio) / dt} × Outrev) is obtained. Further, the coefficient α5 is obtained from the second map from the top in the characteristic group S33. Further, the coefficient α6 is obtained from the third characteristic diagram from the top in the characteristic group S33. These characteristics are determined in the same manner as the characteristic group S3, for example.

  Next, the multiplier S34 multiplies the basic upper limit value of the target input rotational speed change rate drev by the coefficients α5 and α6, respectively, and the target input rotational speed change rate {d (Ratio) / dt} × Outrev upper limit value before tilt restriction. Ask for. Furthermore, the multiplier S35 multiplies the previous value of the post-restricted target gear ratio change rate d (Ratio) / dt upper limit value, which will be described later, and the actual output speed Outrev as the immediately preceding post-restricted target gear ratio change rate upper limit value. Thus, the previous value target input rotational speed change rate {d (Ratio) / dt} × Outrev upper limit value is obtained, and for example, a predetermined change ddrev in one process is increased in accordance with an increase in the vehicle speed VSP. Based on the determined characteristic diagram S36, the change ddrev in one process is obtained from the current vehicle speed, and the adder S37 calculates the change rate of the previous target input speed {d (Ratio) / dt} × Outrev. The change amount ddrev in this process is added to the upper limit value as a limit value, and the target input rotational speed change rate {d (Ratio) / dt} × Outrev limit upper limit value is obtained.

  Then, in the comparator S38, the target input speed change rate {d (Ratio) / dt} × Outrev limit upper limit value and the target input speed change rate {d (Ratio) / dt} × Outrev upper limit value obtained in the multiplier S34. Compared with the value, select the smaller value (close to zero) and set the target input speed change rate after restriction to limit the change gradient {d (Ratio) / dt} x Outrev upper limit value and divide In the controller S39, the post-restriction target input speed change rate {d (Ratio) / dt} × Outrev upper limit value is divided by the actual transmission output speed Outrev to obtain the post-restriction target speed change rate d (Ratio) / dt Find the upper limit. The current value of the post-restriction target gear ratio change rate d (Ratio) / dt upper limit value is input to and held in the holding (delay) unit (1 / z) S40, and the previous value is stored in the multiplier S35 during the next processing. give.

  On the other hand, the subtracter S41 obtains the rotational speed deviation erev between the basic target input rotational speed DsrREV and the transmission actual input rotational speed in the same manner as the subtractor S32, and then from the rotational speed deviation erev by the characteristic group S42. In the same manner as in the characteristic group S33, the basic lower limit value and the coefficients α7 and α8 of the target input rotational speed change rate drev (that is, {d (Ratio) / dt} × Outrev) are obtained. Next, the multiplier S43 multiplies the basic lower limit value of the target input rotational speed change rate drev by the coefficients α7 and α8 to obtain the target input rotational speed change rate {d (Ratio) / dt} × Outrev lower limit value, and converts it. The code is converted in the unit S44.

  Further, the multiplier S45 multiplies the previous value of the post-restriction target speed ratio change rate d (Ratio) / dt lower limit value and the actual output rotational speed Outrev as the post-restriction target speed ratio change rate lower limit value. Characteristic line determined to obtain the previous value target input rotation speed change rate {d (Ratio) / dt} x Outrev lower limit value and to increase the amount of change ddrev in one process as the vehicle speed VSP increases, for example Based on FIG. S46, a change ddrev in one process is obtained from the current vehicle speed, and the sign is converted by the converter S47, and then the previous value target input rotation speed change rate {d ( Ratio) / dt} × Outrev lower limit value is added to the change amount −ddrev in this processing as a limit value to obtain a target input rotational speed change rate {d (Ratio) / dt} × Outrev limit lower limit value.

  Then, in the comparator S49, the target input speed change rate {d (Ratio) / dt} × Outrev lower limit value and the target input speed change rate {d (Ratio) / dt} × Outrev lower limit value passed through the converter S44. And select the larger value (close to zero), and set the target input speed change rate after restriction to limit the slope of change {d (Ratio) / dt} x Outrev lower limit value. In S50, the post-restricted target input speed change rate {d (Ratio) / dt} × Outrev lower limit value is divided by the transmission actual output rotational speed Outrev to obtain the post-restricted target speed change rate d (Ratio) / dt lower limit. Find the value. The current value of the post-restriction target gear ratio change rate d (Ratio) / dt lower limit value is input to and held in the holding (delay) unit (1 / z) S51, and the previous value is stored in the multiplier S45 during the next processing. give. In this way, the upper and lower limit values of the target input speed change rate and the post-restriction target input speed change rate and the upper and lower limit values of the post-restriction target speed ratio change rate are obtained.

  Furthermore, calculation is performed from the basic target speed ratio obtained by dividing the basic target input speed DsrREV by the transmission actual output speed Outrev and the upper and lower limits of the target speed ratio change rate d (Ratio) / dt after the limit. In step S52, the corrected target gear ratio vTGTRTO0, which is the gear ratio after limiting the change gradient of the target gear ratio change rate d (Ratio) / dt, is calculated. Here, the arithmetic unit S52 limits the speed ratio deviation (the rate of change over time of the speed ratio) between the basic target speed ratio and the previous value of the corrected target speed ratio vTGTRTO0 in the same manner as the arithmetic unit S10 in the first embodiment. When the gear ratio deviation is between the upper limit value and lower limit value of the target gear ratio change rate d (Ratio) / dt after restriction compared to the upper and lower limit values of the target gear ratio change rate d (Ratio) / dt Outputs the basic target gear ratio as the current value of the corrected target gear ratio vTGTRTO0, and the gear ratio deviation deviates between the upper limit value and lower limit value of the target gear ratio change rate d (Ratio) / dt after limitation. The corrected target transmission gear ratio vTGTRTO0 is added to the previous value of the post-restriction target transmission gear ratio change rate d (Ratio) / dt plus the lower side of the upper limit value and lower limit value. Output as the current value of target gear ratio vTGTRTO0.

  Then, the current value of the corrected target gear ratio vTGTRTO0 is input to and held in the holding (delay) unit (1 / z) S53 and is given as the previous value to the multiplier S31 in the next processing, and the corrected target gear ratio The current value of vTGTRTO0 is output to the belt-type continuously variable transmission 3, and the gear ratio of the belt-type continuously variable transmission 3 is changed so as to realize the current value of the corrected target gear ratio vTGTRTO0.

FIG. 8 shows the time variation of each factor when the shift control at the time of sudden depression of the accelerator pedal is performed by the transmission control device 7 of the third embodiment and only d (Ratio) / dt × Outrev is limited. become. That is, in the third embodiment, after the accelerator pedal is suddenly depressed (accelerator pedal opening APO step-like increase), the vehicle speed increases and the transmission output rotation Outrev increases to respond to an increase in the vehicle speed VSP in the shift map. As a result, the basic target input speed DsrREV also increases. At this time, if the change in the throttle opening TVO does not cross the shift line, it rises gently as shown by the solid line, and if the change in the throttle opening TVO crosses the shift line, it rises gently as shown by the broken line once. To rise. If the rate of change of the basic target input rotational speed DsrREV during this gentle rise is 700 rpm / sec, for example, while the target d {d (Ratio) / dt × Outrev} / dt upper limit is 500 rpm / sec ² Then, the rate of change (slope) of the basic target input speed DsrREV due to the increase in vehicle speed, that is, the slope of the actual input speed Inprev is not restricted, but is maintained at 700 rpm / sec as shown by the solid line, and rises due to a change in the gear ratio As shown by the broken line, only the acceleration is limited so that it does not exceed 500 rpm / sec ² . Therefore, since the increase in the actual input speed Inprev according to the increase in the actual output speed Outrev is not limited in the actual input speed Inprev / the actual output speed Outrev of the transmission, it is indicated by a broken line when changing the gear ratio. Thus, it is possible to ensure followability of the shift map to the shift line. In addition, when the gear ratio is fixed as instructed by the gear ratio control device 7 by operating a shift lever (not shown) to the manual gear shift mode, the basic upper and lower limit values of the target input rotation speed change rate drev are set to zero. As shown by the solid line, the gear ratio Ratio can be kept constant.

  Accordingly, the multipliers S31, S34, S43, the subtractors S32, S41, the characteristic groups S33, S42, and the retainer S53 correspond to the target input rotation speed change rate upper / lower limit value setting means, and the multipliers S35, S45, the characteristic line. S36, S46, converters S44, S47, adders S37, S48, comparators S38, S49 and retainers S40, S51 correspond to the target gear ratio change rate upper / lower limit value limiting means, and dividers S39, S50 are provided. The post-restricted target gear ratio change rate upper / lower limit value calculating means corresponds, the calculator S52 corresponds to the corrected target gear ratio output means, and the transmission control device 7 corresponds to the gear ratio control means. According to the transmission control device 7 of the third embodiment, the change in the input rotation speed Inprev accompanying the change in the transmission gear ratio Ratio (the first term on the rightmost side of the equation for the change rate of the transmission input rotation speed). However, there is no restriction on the change of the input speed Inprev accompanying the change of the vehicle speed Vsp regardless of the change of the gear ratio Ratio (the second term on the rightmost side of the equation of the change rate of the input speed of the transmission). For example, when the gear ratio Ratio changes due to the throttle opening / closing operation by depressing or returning the accelerator pedal, the change in the input rotation speed Inprev is limited. For example, the throttle opening / closing at a fixed gear ratio in the manual mode When the input rotation speed Inprev changes so as to keep the speed ratio constant by operation, the change is not limited. This limits the slope of the change in the inertia torque that occurs on the transmission input shaft during shift transitions, while maintaining automatic accelerator upshifts while maintaining the accelerator pedal depression amount, and automatic downshifts during coasting while releasing the accelerator pedal. It is possible to ensure the shift line followability of the speed ratio at the time of a steady speed change such as a shift or when the speed ratio is fixed.

  FIG. 9 is a block diagram functionally showing the configuration of the shift control apparatus according to the fourth embodiment of the present invention. In the previous third embodiment, similarly to the first embodiment, the upper and lower limit values of the target input rotational speed change rate drev (that is, {d (Ratio) / dt} × Outrev) are obtained once, and from there, the target gear ratio change rate d Although the upper and lower limit values of (Ratio) / dt are obtained, in the fourth embodiment, the upper and lower limit values of the target gear ratio change rate d (Ratio) / dt are obtained directly as in the second embodiment.

  Specifically, first, the basic target input speed DsrREV is divided by the actual output speed Outrev in the divider S61 to obtain the basic target speed ratio, and then the subtractor S62 corrects the basic target speed ratio described later from the basic target speed ratio. Subtracting the previous value of the rear target gear ratio (the value obtained in the previous processing), the gear ratio deviation (the rate of change over time of the gear ratio) eip is obtained.

  Next, from the speed ratio deviation eip, the target speed ratio change rate d is first determined from the characteristic group S63 in the same manner as in the characteristic group S33 in the third embodiment, based on the uppermost characteristic diagram in the characteristic group S63. Calculate the basic upper limit of (Ratio) / dt. Further, the coefficient β5 is obtained from the second map from the top in the characteristic group S63. Further, the coefficient β6 is obtained from the third characteristic diagram from the top in the characteristic group S63. These characteristics are determined in the same manner as the characteristic group S3, for example. Next, the multiplier S64 multiplies the basic upper limit value of the target speed ratio change rate d (Ratio) / dt by coefficients β5 and β6, respectively, to obtain the target speed ratio change rate d (Ratio) / dt upper limit value.

Further, for example, based on the characteristic diagram S65 determined so that the change d ² (Ratio) / dt ^{2 in} one process increases in accordance with the increase in the vehicle speed VSP, the current vehicle speed can be processed in one process. Change d ² (Ratio) / dt ² , and in adder S66, a post-restriction target speed ratio change rate d (Ratio) / dt upper limit, which will be described later, is used as the immediately previous post-restriction target speed ratio change rate lower limit value. The change d ² (Ratio) / dt ² in the current process is added as a limit value to the previous value of the value to obtain the target gear ratio change rate d (Ratio) / dt limit upper limit value.

  The comparator S67 compares the target gear ratio change rate d (Ratio) / dt limit upper limit value with the target gear ratio change rate d (Ratio) / dt upper limit value obtained by the multiplier S64, and the value is small. Select the direction (close to zero) to set the post-restricted target gear ratio change rate d (Ratio) / dt upper limit value that limits the slope of the change, and this post-restricted target gear ratio change rate d (Ratio) / dt upper limit value Is input to and held in the holding (delay) unit (1 / z) S68, and is supplied as the previous value to the adder S66 in the next processing.

  On the other hand, the subtractor S69 subtracts the previous value of the target gear ratio (the value obtained in the previous processing) from the basic target gear ratio in the same manner as the subtractor S62, and changes the gear ratio deviation (speed change rate of the gear ratio over time) eip. Next, from the speed ratio deviation eip, the basic lower limit value and the coefficients β7 and β8 of the target speed ratio change rate d (Ratio) / dt are obtained by the characteristic group S70 in the same manner as in the characteristic group S63. Next, the multiplier S71 multiplies the basic lower limit value of the target gear ratio change rate d (Ratio) / dt by coefficients β7 and β8, respectively, to obtain the lower limit value of the target gear ratio change rate d (Ratio) / dt, and converts it. The code is converted by the device S72.

Further, as with the characteristic diagram S65, for example, the current vehicle speed is determined based on the characteristic diagram S73 determined so that the change d ² (Ratio) / dt ^{2 in} one process increases as the vehicle speed VSP increases. The change d ² (Ratio) / dt ² in the one-time processing is obtained from the signal, the sign is converted by the converter S74, and the target speed ratio change rate after restriction d (Ratio) / dt is added by the adder S75. The change in the current process (−d ² (Ratio) / dt ² ) is added as a limit value to the previous value of the lower limit value to obtain the target gear ratio change rate d (Ratio) / dt limit lower limit value.

  The comparator S76 compares the target gear ratio change rate d (Ratio) / dt lower limit value with the target gear ratio change rate d (Ratio) / dt lower limit value passed through the converter S72, and the value is large ( Select the one that is closer to zero) to obtain the post-restricted target gear ratio change rate d (Ratio) / dt lower limit value that limits the slope of the change, and the post-restricted target gear ratio change rate d (Ratio) / dt lower limit value. The current value is input to and held in the hold (delay) unit (1 / z) S77, and is given to the adder S75 as the previous value in the next processing. In this way, the upper and lower limit values and the upper and lower limit values of the target speed ratio change rate and the upper and lower limit values of the post-restricted target speed ratio change rate are obtained.

  Furthermore, calculation is performed from the basic target speed ratio obtained by dividing the basic target input speed DsrREV by the transmission actual output speed Outrev and the upper and lower limits of the target speed ratio change rate d (Ratio) / dt after the limit. In step S78, the corrected target transmission gear ratio vTGTRTO0, which is the transmission gear ratio after limiting the target transmission gear ratio change rate d (Ratio) / dt, is calculated. Here, the arithmetic unit S78 limits the speed ratio deviation (the rate of change over time of the speed ratio) between the basic target speed ratio and the previous value of the corrected target speed ratio vTGTRTO0 in the same manner as the arithmetic unit S52 in the third embodiment. Compared with the upper and lower limit values of the rear target gear ratio change rate d (Ratio) / dt, the gear ratio deviation is between the upper limit value and the lower limit value of the target speed ratio change rate d (Ratio) / dt after the limit. In this case, the basic target gear ratio is output as the current value of the corrected target gear ratio vTGTRTO0, and the gear ratio deviation deviates from between the upper limit value and lower limit value of the target gear ratio change rate d (Ratio) / dt after limitation. The corrected target gear ratio vTGTRTO0 is corrected to the previous value of the corrected target gear ratio change rate d (Ratio) / dt by adding the side closer to the gear ratio deviation between the upper limit value and lower limit value. Output as the current value of the rear target gear ratio vTGTRTO0.

  Then, the current value of the corrected target gear ratio vTGTRTO0 is input to and held in the holding (delay) unit (1 / z) S79 and is given as the previous value to the subtracters S62 and S69 in the next processing, and the corrected target The current value of the gear ratio vTGTRTO0 is output to the belt type continuously variable transmission 3, and the speed ratio of the belt type continuously variable transmission 3 is changed so as to realize the current value of the corrected target speed ratio vTGTRTO0.

  Accordingly, the divider S61, the subtracters S62 and S69, the characteristic groups S63 and S70, the multipliers S64 and S71, and the retainer S79 correspond to the target gear ratio change rate upper / lower limit setting means, and the characteristic diagrams S65, S73, Converters S72 and S74, adders S66 and S75, comparators S67 and S76, and retainers S68 and S77 correspond to the post-restriction target speed ratio change rate upper / lower limit value limiting means, and the calculator S78 is the post-correction target speed change. The transmission control device 7 corresponds to a transmission ratio control unit. And also with the transmission control device 7 of the fourth embodiment, as in the previous third embodiment, the change of the input rotation speed Inprev accompanying the change of the transmission gear ratio Ratio (the equation for the rate of change of the transmission input rotation speed) The first term on the rightmost side of the engine), while the input speed Inprev changes with the change in the vehicle speed Vsp regardless of the change in the gear ratio Ratio (the rightmost side of the equation for the change rate of the input speed of the transmission). No restriction is imposed on the second term). For example, when a change in the gear ratio Ratio occurs due to a throttle opening / closing operation by depressing or depressing the accelerator pedal, the change in the input rotational speed Inprev is limited. When the input rotational speed Inprev changes so as to keep the transmission gear ratio constant by the throttle opening / closing operation with the gear ratio fixed, the change is not limited. This restricts the slope of the inertia change over time during shift transitions, while at the time of steady shifts such as automatic upshifts during travel while maintaining the accelerator pedal depression amount and automatic downshifts during coasting travel when the accelerator pedal is released. When the transmission gear ratio is fixed, it is possible to ensure the transmission line followability of the transmission gear ratio.

  Although the present invention has been described based on the illustrated examples, the present invention is not limited to the above-described examples, and can be appropriately changed within the scope of the claims. For example, in the above embodiment, as an automatic transmission Although applied to a belt-type continuously variable transmission, it can also be applied to other types of continuously variable transmissions and stepped automatic transmissions.

  Thus, according to the first aspect of the shift control device for an automatic transmission for a vehicle of the present invention, the target input rotation speed change rate is set as the target gear ratio change rate x the transmission actual output rotation speed, and the upper and lower limit values are set. Since the target gear ratio after correction is obtained by restricting only the target gear ratio change rate by providing, the inertia torque generated on the transmission input shaft during the shift transition is limited, while the accelerator pedal depressing amount maintaining travel is being performed It is possible to ensure the shift ratio followability of the gear ratio at the time of steady gear shift such as automatic upshift or automatic downshift during coasting with the accelerator pedal released, or at a fixed gear ratio setting.

  According to the second aspect of the shift control apparatus for an automatic transmission for a vehicle of the present invention, the corrected target shift is provided by directly setting the upper and lower limit values for the target gear ratio change rate and restricting only the target gear ratio change rate. The ratio is calculated so that the inertia torque generated on the input shaft of the transmission during the shift transition is limited, while the automatic upshift during traveling while maintaining the accelerator pedal depression amount and the automatic downshift during coasting while releasing the accelerator pedal Thus, it is possible to ensure the shift line followability of the gear ratio at the time of a steady gear shift or the like when the gear ratio is fixed.

  Furthermore, according to a third aspect of the shift control apparatus for an automatic transmission for a vehicle of the present invention, in the first aspect, a change in the target speed ratio change rate is provided by providing a limit upper and lower limit value for the target input rotation speed change rate. Since the speed is restricted, the slope of the change over time of the inertia torque during shift transitions is limited, while the automatic upshift while driving with the accelerator pedal depressed and the automatic downshift while coasting with the accelerator pedal released It is possible to ensure the shift line followability of the speed ratio at the time of the steady speed shift or the fixed speed ratio setting.

  According to the fourth aspect of the shift control apparatus for an automatic transmission for a vehicle of the present invention, in the second aspect, the change speed of the target speed ratio change rate is set by providing a limit upper / lower limit value for the target speed ratio change rate. Therefore, while limiting the slope of inertia change over time during shift transitions, automatic upshifting while maintaining the accelerator pedal depression amount, automatic downshifting during coasting with the accelerator pedal released, etc. It is possible to ensure the shift line followability of the speed ratio at the time of steady speed change or speed ratio fixed setting.

DESCRIPTION OF SYMBOLS 1 Car 2 Engine 3 Belt type continuously variable transmission 4 Torque converter with lock-up clutch 5 Tire 6 Engine control unit 7 Transmission control device (target input rotational speed change rate upper / lower limit setting means, target input rotational speed change rate upper / lower limits Value setting means, target input speed change rate upper / lower limit value limiting means, target gear ratio change rate upper / lower limit value calculating means, target gear ratio change rate upper / lower limit value setting means, target gear ratio change rate upper / lower limit value limiting means, limit Rear target gear ratio change rate upper / lower limit value calculating means, corrected target gear ratio output means, speed ratio control means)

Claims (4)

The difference in rotation speed between the basic target input rotation speed set from the throttle opening based on the accelerator pedal depression amount and the vehicle speed, and the input rotation speed obtained by multiplying the previous corrected target gear ratio by the actual output rotation speed. A target input rotational speed change rate upper and lower limit setting means for setting upper and lower limits of the target input rotational speed change rate,
A target speed ratio change rate upper / lower limit value calculating means for obtaining an upper / lower limit value of the target speed ratio change rate by dividing the upper and lower limit values of the target input speed change rate by the actual output speed;
Compare the gear ratio deviation between the basic target speed ratio obtained by dividing the basic target input speed by the actual output speed and the immediately preceding corrected target speed ratio, and the upper and lower limits of the target speed ratio change rate, When the gear ratio deviation does not exceed the upper and lower limits of the target gear ratio change rate, the basic target gear ratio is output as the corrected target gear ratio, and the gear ratio deviation is the upper and lower limits of the target gear ratio change rate. A corrected target gear ratio output means for adding an upper and lower limit value of the target gear ratio change rate to the immediately preceding corrected target gear ratio and outputting the corrected target gear ratio when the value exceeds the corrected target gear ratio;
Based on the corrected target gear ratio, the gear ratio of the automatic transmission for a vehicle that changes the input rotation from the drive source of the vehicle and outputs the output rotation to the drive wheels and automatically changes the gear ratio. Gear ratio control means for
A shift control apparatus for an automatic transmission for vehicles, comprising: The basic target gear ratio obtained by dividing the basic target input speed set by the throttle opening based on the accelerator pedal depression amount of the vehicle and the vehicle speed by the actual output speed, and the gear ratio deviation between the corrected target speed ratio immediately before Target speed ratio change rate upper and lower limit value setting means for setting upper and lower limit values of the target speed ratio change rate based on
The speed ratio deviation is compared with the upper and lower limit values of the target speed ratio change rate. If the speed ratio deviation does not exceed the upper and lower limit values of the target speed ratio change rate, the basic target speed ratio is corrected. When the gear ratio deviation exceeds the upper and lower limit values of the target gear ratio change rate, the correction is performed by adding the upper and lower limit values of the target gear ratio change rate to the immediately preceding corrected target gear ratio. A post-correction target gear ratio output means for outputting the rear target gear ratio;
Based on the corrected target gear ratio, the gear ratio of the automatic transmission for a vehicle that changes the input rotation from the drive source of the vehicle and outputs the output rotation to the drive wheels and automatically changes the gear ratio. Gear ratio control means for
A shift control apparatus for an automatic transmission for vehicles, comprising: The difference in rotation speed between the basic target input rotation speed set from the throttle opening based on the accelerator pedal depression amount and the vehicle speed, and the input rotation speed obtained by multiplying the previous corrected target gear ratio by the actual output rotation speed. A target input rotational speed change rate upper and lower limit setting means for setting upper and lower limits of the target input rotational speed change rate,
Comparing the upper and lower limit values of the target input rotational speed change rate with the target input rotational speed change rate limit upper and lower limit values obtained by adding a predetermined limit value to the target input rotational speed change rate upper and lower limit value immediately before the limit, When the upper and lower limit values of the target input rotational speed change rate do not exceed the upper and lower limit values of the target input rotational speed change rate, the upper and lower limits of the target input rotational speed change rate are limited, and then the upper and lower limits of the target input rotational speed change rate When the upper and lower limit values of the target input speed change rate exceeds the target input speed change rate limit upper and lower limit values, the target input speed change rate limit upper and lower limit values are limited to the target input speed Target input speed change rate upper / lower limit value limiting means for outputting as a change rate upper / lower limit value;
A post-restriction target speed ratio change rate upper / lower limit value calculating means for obtaining an upper / lower limit value of the post-restriction target speed ratio change rate by dividing the upper / lower limit value of the post-restriction target input speed change rate by the actual output speed;
A speed ratio deviation between the basic target speed ratio obtained by dividing the basic target input speed by the actual output speed and the immediately preceding corrected target speed ratio is compared with the upper and lower limit values of the post-restriction target speed ratio change rate. When the speed ratio deviation does not exceed the upper and lower limit values of the post-restriction target speed ratio change rate, the basic target speed ratio is output as the corrected target speed ratio, and the speed ratio deviation is If the upper / lower limit value of the ratio change rate is exceeded, the corrected target gear ratio output is output as the corrected target gear ratio by adding the upper / lower limit value of the post-limit target gear ratio change rate to the immediately preceding corrected target gear ratio. Means,
Based on the corrected target gear ratio, the gear ratio of the automatic transmission for a vehicle that changes the input rotation from the drive source of the vehicle and outputs the output rotation to the drive wheels and automatically changes the gear ratio. Gear ratio control means for
A shift control apparatus for an automatic transmission for vehicles, comprising: The basic target gear ratio obtained by dividing the basic target input speed set by the throttle opening based on the accelerator pedal depression amount of the vehicle and the vehicle speed by the actual output speed, and the gear ratio deviation between the corrected target speed ratio immediately before Target speed ratio change rate upper and lower limit value setting means for setting upper and lower limit values of the target speed ratio change rate based on
The target gear ratio change rate upper / lower limit value is compared with the target gear ratio change rate limit upper / lower limit value obtained by adding a predetermined limit value to the immediately preceding post-restricted target gear ratio change rate upper / lower limit value. When the upper and lower limit values of the ratio change rate do not exceed the target gear ratio change rate limit upper and lower limit values, the upper and lower limit values of the target gear ratio change rate are output as the upper and lower limit target gear ratio change rate, A target that outputs the target speed ratio change rate limit upper / lower limit value as the post-restricted target speed ratio change rate upper / lower limit value when the upper / lower limit value of the target speed ratio change rate exceeds the target speed ratio change rate limit upper / lower limit value Gear ratio change rate upper and lower limit limiting means;
The speed ratio deviation is compared with the upper / lower limit value of the post-restricted target speed ratio change rate, and if the speed ratio deviation does not exceed the upper / lower limit value of the post-limit target speed ratio change rate, the basic target speed ratio is set. When the gear ratio deviation exceeds the upper / lower limit target gear ratio change rate upper / lower limit value, the upper / lower limit target gear ratio change rate upper / lower limit value is added to the immediately preceding target gear ratio. A corrected target gear ratio output means for outputting the corrected target gear ratio;
Based on the corrected target gear ratio, the gear ratio of the automatic transmission for a vehicle that changes the input rotation from the drive source of the vehicle and outputs the output rotation to the drive wheels and automatically changes the gear ratio. Gear ratio control means for
A shift control apparatus for an automatic transmission for vehicles, comprising:

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