JP2010138961A - Transmission having a plurality of transmission routes, and control method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance transmission route switching responsiveness in a transmission having continuously variable transmission routes and direct connection driving routes in parallel. <P>SOLUTION: A transmission controller 300 sets a stand-by gear ratio of a continuously variable transmission mechanism 140, based on a travel state of a vehicle scheduled to be switched from the direct connection driving route to the continuously variable transmission route by a switching mechanism 130, during a period of using the direct connection driving route, and controls the gear ratio of the continuously variable transmission mechanism 140 to the stand-by gear ratio. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a transmission having a plurality of transmission paths, and more particularly to a transmission having a continuously variable transmission path and a direct drive path in parallel.

  Some transmissions include a continuously variable transmission mechanism that changes the transmission gear ratio steplessly and a direct drive mechanism with a fixed transmission gear ratio. In a vehicle equipped with such a transmission, a route for transmitting the rotational driving force from the engine to the output shaft during high-speed traveling is a route through a continuously variable transmission mechanism (hereinafter referred to as a “continuously variable transmission route”). Is switched to a route via the direct drive mechanism (hereinafter referred to as “direct drive route”) to enable driving at a higher gear ratio and reduce friction in the continuously variable transmission mechanism. Fuel efficiency can be improved.

Patent Document 1 discloses that a vehicle equipped with such a transmission has a gear ratio of a continuously variable transmission mechanism when the throttle opening is fully opened at the vehicle speed while traveling using a direct drive path. A technique for controlling in advance to the maximum speed ratio that can be reached is disclosed. According to this control, when the transmission path is switched from the direct drive path to the continuously variable transmission path by kickdown, it is not necessary to change the transmission ratio of the continuously variable transmission mechanism, and the response of kickdown can be improved. it can.
JP-A-62-220755

  However, although the technique of Patent Document 1 can improve the response of kickdown, there is a problem that the switching response is poor when the transmission path is switched by a factor other than kickdown.

  For example, if the transmission path is switched from a direct drive path to a continuously variable transmission path because the driver slowly depresses the accelerator pedal or the vehicle speed decreases, the transmission ratio of the continuously variable transmission mechanism is maximized. It is necessary to change from a gear ratio to a gear ratio determined in accordance with the driving state at that time (a gear ratio in the vicinity of the highest gear ratio). It takes time to shift the continuously variable transmission mechanism, and the transmission path is switched quickly. I can't.

  The present invention has been made in view of such technical problems, and an object of the present invention is to improve transmission path switching responsiveness in a transmission having a continuously variable transmission path and a direct drive path in parallel.

  According to an aspect of the present invention, the steplessly changing the gear ratio steplessly as a transmission path that is mounted on a vehicle equipped with a prime mover and that shifts the rotational driving force input from the prime mover and transmits it to the output shaft. A transmission having a continuously variable transmission path that passes through a transmission mechanism and a direct connection drive path that passes through a direct connection drive mechanism having a fixed gear ratio, and that switches the transmission path by a switching mechanism. Switching control means for determining switching of the transmission path based on the traveling state (hereinafter referred to as “actual traveling state”) and controlling the switching mechanism based on the determination, and the continuously variable transmission path are used. A continuously variable transmission mechanism shift control means for setting a target transmission ratio of the continuously variable transmission mechanism based on the actual running state and controlling the transmission ratio of the continuously variable transmission mechanism to the target transmission ratio; Drive path is used While the vehicle is running, the switching control means switches the transmission path from the directly connected drive path to the continuously variable transmission path to the traveling state of the vehicle (hereinafter referred to as “scheduled switching traveling state”). And a standby shift control means for setting a standby transmission ratio of the continuously variable transmission mechanism to control the transmission ratio of the continuously variable transmission mechanism to the standby transmission ratio. The

  According to another aspect of the present invention, the transmission ratio is steplessly changed as a transmission path that is mounted on a vehicle equipped with a prime mover and that shifts the rotational driving force input from the prime mover and transmits it to the output shaft. A transmission control method that includes a continuously variable transmission path that passes through a continuously variable transmission mechanism and a direct connection drive path that passes through a direct connection drive mechanism with a fixed gear ratio, and switches the transmission path by a switching mechanism. A switching control procedure for determining switching of the transmission path based on a current traveling state of the vehicle (hereinafter referred to as “actual traveling state”), and controlling the switching mechanism based on the determination; While the speed change path is being used, a continuously variable speed change mechanism for setting a target speed change ratio of the continuously variable transmission mechanism based on the actual running state and controlling the speed change ratio of the continuously variable speed change mechanism to the target speed change ratio. Control procedure and direct connection While the moving path is being used, the transmission path is switched from the direct drive path to the continuously variable transmission path by the switching control procedure based on the traveling state of the vehicle. And a standby shift control procedure for setting a standby gear ratio and controlling the gear ratio of the continuously variable transmission mechanism to the standby gear ratio.

  According to these aspects, while the direct drive path is used, the gear ratio of the continuously variable transmission mechanism is controlled in advance to the standby gear ratio corresponding to the traveling state of the vehicle for which the transmission path is scheduled to be switched. Therefore, the amount of change in the gear ratio of the continuously variable transmission mechanism when the transmission path is switched from the direct drive path to the continuously variable transmission path is reduced, and the transmission path switching responsiveness can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the gear ratio is defined as a value obtained by dividing the input-side rotational speed of the transmission mechanism by the output-side rotational speed of the mechanism, the large gear ratio side is “Low side”, and the small gear ratio side is “High”. "Side".

  FIG. 1 is a schematic configuration diagram of a transmission 100 according to an embodiment of the present invention. The transmission 100 is mounted on a vehicle including an engine 200 as a prime mover. The transmission 100 shifts the rotational driving force from the engine 200 input to the input shaft 101 and transmits it to the output shaft 102. The rotational driving force transmitted to the output shaft 102 is transmitted to driving wheels (not shown).

  The transmission 100 includes a torque converter 110 with a lockup mechanism, a direct drive gear train 120 (direct drive mechanism) composed of gears 121 to 123, a switching mechanism 130, a continuously variable transmission mechanism 140, and gears 151 to 153. An output gear train 150 and a differential gear unit 160 are provided.

  The transmission 100 uses a transmission path via the continuously variable transmission mechanism 140 (hereinafter referred to as “continuously variable transmission path”) and a transmission path via the direct drive gear train 120 as a transmission path of the rotational driving force of the engine 200. (Hereinafter referred to as “directly connected drive path”) in parallel, and the transmission path can be switched by the switching mechanism 130.

  The switching mechanism 130 includes a planetary gear mechanism 131, a forward clutch FWD / C, a reverse clutch REV / C, and a high clutch H / C.

  The planetary gear mechanism 131 is disposed between the sun gear S, the ring gear R disposed outside the sun gear S, and between the sun gear S and the ring gear R. The carrier C is freely supported. The sun gear S is connected to the input shaft 141 of the continuously variable transmission mechanism 140, and the ring gear R is connected to the output shaft 111 of the torque converter 110.

  When the forward clutch FWD / C is engaged and the other clutches REV / C and H / C are released, the ring gear R and the sun gear S are connected, and as shown in FIG. 2A, the rotational driving force from the engine 200 is A continuously variable transmission path that is transmitted to the output shaft 102 via the torque converter 110, the switching mechanism 130, the continuously variable transmission mechanism 140, the output gear train 150, and the differential gear unit 160 is formed.

  Further, if the high clutch H / C is engaged and the other clutches FWD / C and REV / C are released, the output shaft 111 of the torque converter 110 and the gear 121 of the direct drive gear train 120 are connected, and FIG. As shown, a direct drive path for transmitting the rotational drive force from the engine 200 to the output shaft 102 via the torque converter 110, the direct drive gear train 120, the output gear train 150, and the differential gear unit 160 is formed. .

  If the reverse clutch REV / C is engaged and the other clutches FWD / C and H / C are released, the transmission path is the same as the path shown in FIG. 2A, but the rotational direction of the rotational driving force of the engine 200 is changed. It can be reversed and transmitted to the output shaft 102.

  The continuously variable transmission mechanism 140 includes a primary pulley 142 connected to the input shaft 141, a secondary pulley 143 connected to the gear 151 of the output gear train 150, and a V belt 144 that is wound around the pulleys 142 and 143. The pulleys 143 and 144 are each provided with a fixed sheave, a movable sheave arranged with the sheave surface facing the fixed sheave and forming a V-groove between the fixed sheave, and a rear surface of the movable sheave. And a hydraulic cylinder (not shown) for displacing the movable sheave in the axial direction.

  When the hydraulic pressure supplied to the hydraulic cylinder is adjusted by the hydraulic control circuit 500, the width of the V groove changes, the contact radius between the V belt 144 and each pulley 142, 143 changes, and the transmission ratio of the continuously variable transmission mechanism 140 is changed. Change steplessly.

  On the other hand, the gear ratio of the direct drive gear train 120 is constant. The gear ratio of the direct drive gear train 120 is set to be higher (smaller) than the highest pulley ratio (minimum gear ratio) of the continuously variable transmission mechanism 140.

  In the following description, the transmission ratio of the continuously variable transmission mechanism 140 is referred to as “pulley ratio”, and the transmission ratio of the transmission 100 is referred to as “unit transmission ratio”. The unit gear ratio is equal to the pulley ratio of the continuously variable transmission mechanism 140 when the continuously variable transmission path is used as the transmission path, and when the direct connection drive path is used as the transmission path, the unit transmission ratio is It is equal to the gear ratio.

  The transmission path switching by the switching mechanism 130 and the pulley ratio of the continuously variable transmission mechanism 140 are controlled by the transmission controller 300.

  As shown in FIG. 3, the transmission controller 300 (switching control means, continuously variable transmission mechanism shift control means, standby shift control means, sudden stepping determination means) includes a CPU 301 and a storage device 302 (shifts) including a RAM / ROM. Map storage means, switching map storage means), an input interface 303, an output interface 304, and a bus 305 for interconnecting them.

  The input interface 303 includes an output signal of the inhibitor switch 311 that detects the position of the select lever, and a rotation speed sensor 312 that detects the input side rotation speed of the continuously variable transmission mechanism 140 (hereinafter referred to as “primary rotation speed Pri”). An output signal, an output signal of a vehicle speed sensor 313 for detecting the vehicle speed Vsp, and the like are input.

  In addition, a signal indicating the throttle opening TVO of the engine 200, a signal indicating the rotational speed of the engine 200, and the like are input from the engine controller 400 to the input interface 303 as signals indicating the running state of the engine 200.

  The storage device 302 stores a control program, a shift map (FIG. 4) and a switching map (FIG. 5) used in the control program. The shift map is used to control the pulley ratio of the continuously variable transmission mechanism 140, and the switching map is used to determine switching between the continuously variable transmission path and the direct drive path.

  The CPU 301 reads out and executes a control program stored in the storage device 302, performs various arithmetic processes on various signals input via the input interface 303, generates a control signal, and generates the generated control signal. Output to the hydraulic control circuit 500 via the output interface 304. Various values used in the arithmetic processing by the CPU 301 and the arithmetic results are appropriately stored in the storage device 302.

  The hydraulic control circuit 500 includes a plurality of flow paths and a plurality of hydraulic control valves. Based on the control signal from the transmission controller 300, the hydraulic control circuit 500 controls a plurality of hydraulic control valves to switch the hydraulic pressure supply path and prepares the necessary hydraulic pressure from the hydraulic pressure generated by the oil pump. The pulleys 142 and 143 of the step transmission mechanism 140 and the clutches FWD / C, REV / C, and H / C of the switching mechanism 130 are supplied. As a result, the pulley ratio of the continuously variable transmission mechanism 140 is changed, and the transmission path is switched by the switching mechanism 130.

  FIG. 4 shows an example of the shift map. When the continuously variable transmission path is selected as the transmission path, the shift map is referred to based on the vehicle traveling state defined by the current vehicle speed Vsp and the throttle opening TVO (hereinafter referred to as “actual traveling state”). The target primary rotational speed tPri obtained in this way is set, and the pulley ratio of the continuously variable transmission mechanism 140 is controlled so that the actual primary rotational speed Pri becomes the target primary rotational speed tPri.

  Since the slope of the line connecting the point on the map and the origin corresponds to the pulley ratio of the continuously variable transmission mechanism 140, the pulley ratio of the continuously variable transmission mechanism 140 is set so that the target primary rotational speed tPri is set and realized. Control is equivalent to setting the target pulley ratio (corresponding to the target primary rotational speed tPri) and controlling the pulley ratio of the continuously variable transmission mechanism 140 so that this is realized. Express.

  In addition to the shift line of the continuously variable transmission mechanism 140, the shift map shows the relationship (broken line) between the vehicle speed Vsp and the primary rotational speed Pri when the direct drive path is selected as the transmission path. Since the direct drive gear train 120 has a fixed gear ratio, the relationship between the vehicle speed Vsp and the primary rotational speed Pri is expressed by a straight line passing through the origin. The F / C recover rotational speed is a primary rotational speed that returns from the fuel cut state, and in the coast state, a shift is performed so that the primary rotational speed Pri does not fall below the F / C recover rotational speed as much as possible. In addition, while a direct drive path is used, a standby line (one-dot chain line) indicating which pulley ratio the continuously variable transmission mechanism 140 is on standby is shown, which will be described later.

  On the shift map, R / L lines (thick lines) for determining whether or not the driving force is insufficient when switching from the continuously variable transmission path to the direct drive path are set for each road gradient. In this figure, for simplicity, only the R / L line when the road surface gradient is 0% is shown. The R / L line represents the minimum primary rotational speed at which the vehicle can maintain the current vehicle speed with the road gradient, that is, the minimum unit speed ratio (hereinafter referred to as “allowable minimum unit speed ratio”). It can be determined whether or not the driving force is insufficient based on whether the unit speed ratio realized by selecting the step speed change path or the direct drive path is larger than the allowable minimum unit speed ratio.

  FIG. 5 shows an example of the switching map. On the switching map, the transmission path is continuously switched from the continuously variable transmission path to the direct drive path, continuously to the direct connection switching line (solid line). Two switching lines of lines (broken lines) are set.

  When a continuously variable transmission path is used as the transmission path, if the point on the map determined based on the actual driving state crosses the continuously variable → direct connection line from the left area to the right area, the driving force is secured after switching. The transmission path is switched from the continuously variable transmission path to the direct drive path on condition that it is possible and is not during sports driving. By switching the transmission path to the direct drive path, it is possible to drive at a higher gear ratio, reduce friction in the continuously variable transmission mechanism, and improve the fuel efficiency of the vehicle.

  On the other hand, when the direct drive path is selected as the transmission path, if the point on the map determined based on the actual driving state is directly connected → the stepless switching line crosses from the right area to the left area, the transmission path is The direct drive path is switched to the continuously variable transmission path.

  The standby line setting method of the continuously variable transmission mechanism 140 shown in FIG. 4 will be described. As shown in FIG. 6, the standby line of the continuously variable transmission mechanism 140 shows the shift map shown in FIG. 4 and the switching map shown in FIG. By projecting the direct connection → continuously variable switching line on the switching map onto the shift map, that is, projecting each traveling state of the vehicle corresponding to the direct connection → continuously variable switching line onto the shift map. Is set by

In the example shown in FIG. 6, based on the switching map, driving states X _{1 to} X in which the transmission path is switched by obtaining the vehicle speed Vsp at which the transmission path is switched from the direct drive path to the continuously variable transmission path for each throttle opening TVO. ₆ are obtained, plotted on the shift map, and the standby points of the continuously variable transmission mechanism 140 are set by connecting the plotted points X ′ _{1 to} X ′ ₆ .

  As described above, while the continuously variable transmission path is selected as the transmission path, the target pulley ratio is set according to the shift map shown in FIG. 4, and the pulley ratio of the continuously variable transmission mechanism 140 is controlled to the target pulley ratio. On the other hand, while the direct drive path is selected as the transmission path, the travel state on the standby line (virtual travel state) is set as the travel state of the vehicle scheduled to be switched from the direct drive path to the continuously variable transmission path. ) And the pulley ratio of the continuously variable transmission mechanism 140 is controlled so that the standby pulley ratio determined by the vehicle speed and the standby line at that time is realized.

  7A and 7B show an example of a control program stored in the storage device 302 of the transmission controller 300. FIG. The contents of control executed by the transmission controller 300 will be specifically described with reference to this.

  Steps S1 to S4 are controls when a continuously variable transmission path is used as the transmission path.

  In step S1, it is determined whether the vehicle is traveling on a continuously variable transmission path. If it is determined that the vehicle is traveling on the continuously variable transmission path, the process proceeds to step S2. In contrast, if it is determined that the vehicle is not traveling on the continuously variable transmission path, that is, if it is determined that the vehicle is traveling on the direct drive path, the process proceeds to step S5.

  In step S2, it is determined whether a switching condition from the continuously variable transmission path to the direct drive path is satisfied. For example, it is determined that the switching condition from the continuously variable transmission path to the direct drive path is satisfied when all of the following conditions are satisfied.

  ・ The actual running state on the switching map is stepless → crossed the direct switching line from the left area to the right area.

  The pulley ratio of the continuously variable transmission mechanism 140 is the highest pulley ratio.

  ・ Sport is not running.

  -Even if the transmission path is switched from the continuously variable transmission path to the direct drive path, the driving force is not insufficient.

  The condition that the pulley ratio of the continuously variable transmission mechanism 140 is the highest pulley ratio is to reduce the shock at the time of switching and the direct drive path is when the continuously variable transmission mechanism 140 is at the highest pulley ratio. This is because the path is provided for the purpose of reducing the friction in the continuously variable transmission mechanism 140.

  Whether the sport is running depends on the position of the select lever (for example, when the select lever is in the S range), the operation state of other switches (when the sport running switch provided separately from the select lever is ON), or the vehicle behavior to decide.

  Whether or not the driving force is insufficient is determined using the allowable minimum unit speed ratio at the vehicle speed Vsp obtained from the R / L line, and the gear ratio of the direct drive gear train 120 is greater than the allowable minimum unit speed ratio. If it is larger, it is determined that the driving force is not insufficient.

  Whether the driving force is insufficient is determined by calculating the running resistance based on the vehicle speed Vsp and the road surface gradient in addition to the method using the R / L line, and the torque of the engine 200 and the direct drive gear train 120 at that time. It may be determined by determining whether the driving force determined from the transmission ratio exceeds the running resistance.

  If it is determined that the condition for switching from the continuously variable transmission path to the direct drive path is satisfied, the process proceeds to step S3, and if not, step S2 is repeated.

  In step S3, a process of switching the transmission path from the continuously variable transmission path to the direct drive path by clutch switching control is executed. Specifically, the high clutch H / C is engaged while releasing the forward clutch FWD / C, and the clutch that forms the transmission path is switched.

  In step S4, it is determined whether or not the transmission path has been switched. If the switching has been completed, the process proceeds to step S5. Otherwise, steps S3 and S4 are repeated.

  On the other hand, steps S5 to S8 are controls when the direct drive path is used as the transmission path.

  In step S5, the pulley ratio of the continuously variable transmission mechanism 140 is controlled to a standby pulley ratio determined by the vehicle speed Vsp and the standby line at that time.

  In step S6, it is determined whether a switching condition from the direct drive path to the continuously variable transmission path is satisfied. For example, it is determined that the switching condition from the direct drive path to the continuously variable transmission path is satisfied when the actual travel state crosses the direct connection → continuously variable switching line from the right region to the left region on the switching map.

  If it is determined that the switching condition from the direct drive path to the continuously variable transmission path is satisfied, the process proceeds to step S7, and if not, steps S5 and S6 are repeated. By repeating this, while the direct drive path is used, the pulley ratio of the continuously variable transmission mechanism 140 is controlled to the standby pulley ratio.

  In step S7, the transmission path is switched from the direct drive path to the continuously variable transmission path. This process is performed by the process shown in FIG. 7B.

  According to the process shown in FIG. 7B, first, in step S71, it is determined whether or not the accelerator pedal is suddenly depressed based on the throttle opening TVO. Whether the accelerator pedal is suddenly depressed can be determined from, for example, changes in the throttle opening TVO (change amount, change speed), but may be determined by directly detecting the accelerator pedal depression amount.

  If it is determined that the accelerator pedal is suddenly depressed, the process proceeds to step S72, and a process of switching the transmission path from the direct drive path to the continuously variable transmission path is executed by synchronous control. Specifically, shifting of the continuously variable transmission mechanism 140 is started so that the pulley ratio of the continuously variable transmission mechanism 140 becomes a target pulley ratio determined according to the actual traveling state, and the high clutch H / C is released to perform the shifting. The machine 100 is temporarily set to a neutral state in which the output rotation of the engine 200 is not transmitted to the output shaft, and in this state, synchronous control for synchronizing the rotation speed of the engine 200 with the primary rotation speed Pri of the continuously variable transmission mechanism 140 is started. Then, when the pulley ratio of continuously variable transmission mechanism 140 becomes the target pulley ratio and the rotational speed of engine 200 is synchronized with primary rotational speed Pri of continuously variable transmission mechanism 140, forward clutch FWD / C is engaged.

  On the other hand, if it is determined that the accelerator pedal has not been depressed suddenly, the process proceeds to step S73, and a process of switching the transmission path from the direct drive path to the continuously variable transmission path is executed by the switching control. Specifically, the continuously variable transmission mechanism 140 is shifted so that the pulley ratio of the continuously variable transmission mechanism 140 becomes a target pulley ratio determined according to the actual traveling state, and then the forward clutch FWD / C is released and the high speed is increased. By engaging the clutch H / C, the clutch that forms the transmission path is switched.

  Returning to FIG. 7A, in step S8, it is determined whether switching of the transmission path has been completed. If switching has been completed, the process returns to step SS1. Otherwise, steps S7 and S8 are repeated.

  Then, the effect by performing said control is demonstrated.

FIG. 8A shows a case where the vehicle speed Vsp increases when the continuously variable transmission path is selected, the actual running state changes from X ₁₁ to X ₁₂ and crosses the continuously variable to direct connection switching line. 8B is a time chart corresponding to this time.

  In FIG. 8B, at time t11, when the actual running state crosses the continuously variable to direct connection switching line, it is determined that the transmission path is switched from the continuously variable transmission path to the direct drive path, and the switching of the transmission path is started.

  This switching is performed by lowering and releasing the hydraulic pressure supplied to the forward clutch FWD / C, and increasing and fastening the hydraulic pressure supplied to the high clutch H / C, and switching the clutch that forms the transmission path. Done. As the clutch changeover proceeds, the unit gear ratio changes from the pulley ratio of the continuously variable transmission mechanism 140 to the gear ratio of the direct drive gear train 120, and the rotational speed of the engine 200 also changes accordingly.

  When the clutch switching is completed at time t12 and the switching of the transmission path is completed, the pulley ratio of the continuously variable transmission mechanism 140 is controlled to a standby pulley ratio determined by the vehicle speed Vsp and the standby line.

FIG. 9A shows a case where the accelerator pedal is depressed slowly when the direct drive path is selected, and the actual running state changes from X ₂₁ to X ₂₂ and crosses the direct connection → continuous switching line. FIG. 9B is a time chart corresponding to this time.

  In FIG. 9B, when the actual traveling state crosses the direct connection → continuously variable line at time t21, it is determined that the transmission path is switched from the direct drive path to the continuously variable transmission path, and transmission path switching is started.

  In switching, first, the pulley ratio of the continuously variable transmission mechanism 140 is controlled to a target pulley ratio corresponding to the actual running state. While the direct drive path is used, the pulley ratio of the continuously variable transmission mechanism 140 is controlled to the standby pulley ratio in advance, so that the amount of change in the pulley ratio is minimized, and in this example, the amount of change is zero. Next, the hydraulic pressure supplied to the high clutch H / C is reduced and released, and the hydraulic pressure supplied to the forward clutch FWD / C is increased and engaged to start changing clutches that form a transmission path.

  As the clutch changeover proceeds, the unit gear ratio changes from the gear ratio of the direct drive gear train 120 to the pulley ratio of the continuously variable transmission mechanism 140, and the rotational speed of the engine 200 also changes accordingly.

  When the clutch switching is completed at time t22 and the switching of the transmission path is completed, the pulley ratio of the continuously variable transmission mechanism 140 is controlled to a target pulley ratio determined according to the actual running state.

  Thus, according to the above control, while the direct drive path is used, the pulley ratio of the continuously variable transmission mechanism 140 is set to the standby pulley ratio corresponding to the traveling state of the vehicle where the transmission path is scheduled to be switched. Since the control is performed in advance, the amount of change in the pulley ratio of the continuously variable transmission mechanism 140 when the transmission path is switched can be reduced, and the transmission path switching response can be improved. ).

  In particular, when the transmission path is switched by slowly depressing the accelerator or when the vehicle speed Vsp decreases, the standby pulley ratio matches the target pulley ratio set based on the actual traveling state, and the transmission path Since there is no need to shift the continuously variable transmission mechanism 140 before and after the switching, the effect of improving the switching response is great.

FIG. 10A shows a case where the accelerator pedal is suddenly depressed to the maximum amount when the direct drive route is selected, and the actual driving state changes from X ₃₁ to X ₃₂ and crosses the direct connection → continuous switching line. FIG. 10B is a time chart corresponding to this time.

  In FIG. 10B, when the actual running state crosses the direct connection → continuously variable line at time t31, it is determined that the transmission path is switched from the direct drive path to the continuously variable transmission path, and transmission path switching is started.

  In switching, first, the change of the pulley ratio of the continuously variable transmission mechanism 140 is started. The target pulley ratio at this time is a pulley ratio determined according to the actual traveling state.

  Next, at time t32, the hydraulic pressure supplied to the high clutch H / C is reduced, and the high clutch H / C is released. When the high clutch H / C is released and the transmission 100 is in the neutral state, synchronous control for making the rotational speed of the engine 200 equal to the primary rotational speed Pri is started.

  When the speed change of the continuously variable transmission mechanism 140 is completed and the rotational speed of the engine 200 is synchronized with the primary rotational speed Pri, the hydraulic pressure supplied to the forward clutch FWD / C is increased, and the forward clutch FWD / C starts to be engaged. Is done.

  When the engagement of the forward clutch FWD / C is completed at time t33 and the switching of the transmission path is completed, thereafter, the pulley ratio of the continuously variable transmission mechanism 140 is controlled to a target pulley ratio determined according to the actual traveling state.

  While the direct drive path is used, the pulley ratio of the continuously variable transmission mechanism 140 is controlled to the pulley ratio on the standby line. When the accelerator pedal is suddenly depressed and the transmission path is switched from the direct drive path to the continuously variable transmission path, the target pulley ratio of the continuously variable transmission mechanism 140 is significantly changed to the low side. The amount of change in the pulley ratio increases.

  However, according to the above control, since synchronous control is performed in such a case, the time required for shifting the continuously variable transmission mechanism 140 is shorter than that in the case where the switching control is performed, and the response of switching the transmission path is improved. (Corresponding to claim 4).

  In the example shown in FIG. 10B, it is assumed that the time point at which shifting of the continuously variable transmission mechanism 140 is started is earlier than the time point at which the release of the high clutch H / C is started. At the same timing, if the speed change of the continuously variable transmission mechanism 140 is not completed before the rotational speed of the engine 200 is synchronized with the primary rotational speed Pri of the continuously variable transmission mechanism 140, the speed change of the continuously variable transmission mechanism 140 is completed. This is because the forward clutch FWD / C cannot be engaged until it is necessary to wait for the transmission 100 to remain in the neutral state, and the idling time becomes longer and the drivability deteriorates.

  The embodiment of the present invention has been described above, but the above embodiment is merely one example of application of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. is not.

  For example, in the above embodiment, the gear ratio of the direct drive gear train 120 is set to be higher than the highest pulley ratio of the continuously variable transmission mechanism 140. However, the present invention is not limited to this. The present invention can also be applied to a gear that has the gear ratio of the direct drive gear train 120 set equal to or higher than the highest pulley ratio of the continuously variable transmission mechanism 140.

  Further, in the above embodiment, when performing synchronous control by switching from the direct drive path to the continuously variable transmission path, the continuously variable transmission mechanism 140 starts shifting first, and then the high speed is increased in order to shorten the idle time. Although the hydraulic pressure reduction of the clutch H / C is started, it is not limited to this. For example, the continuously variable transmission is greater than the sum of the time until the high clutch H / C is released and the time required to synchronize the rotational speed of the engine 200 with the primary rotational speed Pri after the high clutch H / C is released. When the time until the gear shift of the mechanism 140 is completed is short, the gear shift of the continuously variable transmission mechanism 140 and the hydraulic pressure reduction of the high clutch H / C may be started simultaneously. Or you may set the timing which starts the hydraulic pressure fall of the high clutch H / C according to the time until the speed change of the continuously variable transmission mechanism 140 is completed.

  In the above embodiment, the synchronization control is performed when the direct drive path is switched to the continuously variable transmission path by sudden depression of the accelerator pedal, but the synchronization control is not essential, for example, when the accelerator pedal is depressed slowly. Similarly, the clutch ratio may be changed after the pulley ratio of the continuously variable transmission mechanism 140 is controlled to a target pulley ratio determined according to the actual traveling state.

  In the above-described embodiment, the continuously variable transmission mechanism 140 includes a belt-type continuously variable transmission mechanism. However, the continuously variable transmission mechanism 140 can be changed to other mechanisms (for example, toroidal type) as long as the gear ratio can be changed continuously. Continuously variable transmission mechanism).

1 is a schematic configuration diagram of a transmission 100 according to an embodiment of the present invention. It is the figure which showed the continuously variable transmission path | route. It is the figure which showed the direct drive path. 2 is a diagram showing an internal configuration of a transmission controller 300. FIG. 4 is a shift map used for shift control of continuously variable transmission mechanism 140. It is a transmission switching map which determines switching of a transmission path. It is a figure for demonstrating the setting method of a standby line. It is the flowchart which showed the contents of the main routine of the transmission control program. It is the flowchart which showed the content of the subroutine of the transmission control program. It is a figure for demonstrating operation | movement when the vehicle speed Vsp increases when the continuously variable transmission path | route is selected and an actual driving | running | working state crosses the continuously variable-> direct connection switching line. It is a time chart corresponding to FIG. 8A. It is a figure for demonstrating operation | movement when an accelerator pedal is stepped on slowly when the direct drive path is selected, and an actual driving state crosses a direct connection-> continuously variable switching line. It is a time chart corresponding to FIG. 9A. It is a figure for demonstrating operation | movement when an accelerator pedal is stepped on to the maximum amount suddenly when the direct connection drive path | route is selected, and an actual driving state crosses the direct connection-> continuously variable switching line. It is a time chart corresponding to FIG. 10A.

Explanation of symbols

100 Transmission 120 Gear train for direct drive (direct drive mechanism)
130 switching mechanism 140 continuously variable transmission mechanism 200 engine (prime mover)
300 Transmission controller (switching control means, continuously variable transmission mechanism shift control means, standby shift control means, sudden depression determination means)
302 Storage device (shift map storage means, switching map storage means)

Claims (5)

A continuously variable transmission path that is mounted on a vehicle equipped with a prime mover and that passes through a continuously variable transmission mechanism that changes the transmission ratio steplessly as a transmission path that shifts the rotational driving force input from the prime mover and transmits it to the output shaft. And a direct-coupled drive path via a direct-coupled drive mechanism with a fixed gear ratio, and a transmission that switches the transmission path by a switching mechanism,
Switching control means for determining switching of the transmission path based on a current traveling state of the vehicle (hereinafter referred to as “actual traveling state”), and for controlling the switching mechanism based on the determination;
While the continuously variable transmission path is used, the continuously variable transmission mechanism sets a target transmission ratio of the continuously variable transmission mechanism based on the actual running state, and controls the transmission ratio of the continuously variable transmission mechanism to the target transmission ratio. Transmission mechanism shift control means;
While the direct drive path is being used, the switching control means switches the transmission path from the direct drive path to the continuously variable transmission path (hereinafter referred to as “switching schedule”). A standby transmission gear ratio control means for setting a standby transmission gear ratio of the continuously variable transmission mechanism based on the running state and controlling the transmission gear ratio of the continuously variable transmission mechanism to the standby transmission gear ratio;
A transmission comprising: The transmission according to claim 1,
The planned switching traveling state is a traveling state of the vehicle in which the transmission path is scheduled to be switched from the direct drive path to the continuously variable transmission path by the switching control means at a current vehicle speed.
A transmission characterized by that. The transmission according to claim 2,
The traveling state is a traveling state defined by a vehicle speed and a throttle opening of the prime mover,
Shift map storage means for storing a shift map that defines the relationship between the traveling state and the target gear ratio of the continuously variable transmission mechanism, and which of the continuously variable transmission path and the direct drive path is used based on the traveling state Switching map storage means for storing a switching map that defines
With
The switching control means determines switching with the transmission path by referring to the switching map based on the actual running state,
The continuously variable transmission mechanism shift control means sets the target gear ratio by referring to the shift map based on the actual running state while the continuously variable transmission path is used.
While the direct drive path is being used, the standby shift control means changes the planned switching state from the direct drive path to the continuously variable transmission path at the current vehicle speed and the current vehicle speed based on the switching map. The throttle opening degree that is scheduled to be switched is defined, and the standby gear ratio is set with reference to the shift map based on the planned switching traveling state.
A transmission characterized by that. The transmission according to claim 3, wherein
When the switching control means determines that the direct drive path is switched to the continuously variable transmission path, it includes sudden depression determination means for determining whether the accelerator pedal has been suddenly depressed based on a change in the throttle opening,
The switching control means is
If it is determined by the sudden depression determination means that the accelerator pedal has been suddenly depressed, the target transmission ratio is set by referring to the transmission map based on the actual running state, and the transmission ratio of the continuously variable transmission mechanism Is set to the target gear ratio, and the transmission is set to a neutral state in which the rotational driving force from the prime mover is not transmitted to the output shaft. The rotational speed of the prime mover is set to the input side of the continuously variable transmission mechanism. Start synchronous control to synchronize with the rotation speed,
The transmission path is switched to the continuously variable transmission path after the transmission gear ratio of the continuously variable transmission mechanism becomes the target transmission gear ratio and the rotational speed of the prime mover is synchronized with the input side rotational speed of the continuously variable transmission mechanism. Controlling the switching mechanism,
A transmission characterized by that. A continuously variable transmission path that is mounted on a vehicle equipped with a prime mover and that passes through a continuously variable transmission mechanism that changes the transmission ratio steplessly as a transmission path that shifts the rotational driving force input from the prime mover and transmits it to the output shaft. And a direct-coupled drive path via a direct-coupled drive mechanism with a fixed gear ratio, and a transmission control method for switching the transmission path by a switching mechanism,
A switching control procedure for determining switching of the transmission path based on a current traveling state of the vehicle (hereinafter referred to as “actual traveling state”), and controlling the switching mechanism based on the determination;
While the continuously variable transmission path is used, the continuously variable transmission mechanism sets a target transmission ratio of the continuously variable transmission mechanism based on the actual running state, and controls the transmission ratio of the continuously variable transmission mechanism to the target transmission ratio. A transmission mechanism shift control procedure;
While the direct drive path is used, the continuously variable transmission is based on the traveling state of the vehicle where the transmission path is scheduled to be switched from the direct drive path to the continuously variable transmission path by the switching control procedure. A standby gear ratio control procedure for setting a standby gear ratio of the mechanism and controlling the gear ratio of the continuously variable transmission mechanism to the standby gear ratio;
A transmission control method comprising:

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