JPS62137239A - Method of controlling continuously variable transmission provided with subtransmission for vehicle - Google Patents

Abstract

PURPOSE:To enable a drive force of a vehicle to be sufficiently displayed by providing a means for memorizing a plurality of types of speed change patterns to select the speed change pattern corresponding to the travelling property of a vehicle. CONSTITUTION:One of a plurality of types of speed change patterns memorized in ROM 56 of memory is selected according tot he operation of a travelling property selecting switch 82. At the same time, the gear stage of a subtransmission 30 is automatically changed over from that speed change pattern. Thus, even if a shift lever 66 is maintained at the usual travelling range, the output of an engine 10 can be sufficiently displayed according to the operation of said switch 82 so that strong travelling can be obtained from a large drive force if necessary.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to an improvement in a control device for a continuously variable transmission for a vehicle equipped with an auxiliary transmission.

BACKGROUND OF THE INVENTION Vehicles are known that are equipped with a continuously variable vehicular transmission that has an auxiliary transmission that can be switched to two or more forward gears. In such a vehicle, for example, the auxiliary transmission is automatically switched to one of its forward gears based on the throttle valve opening and vehicle speed based on a predetermined shift pattern, and the throttle is changed based on a predetermined relationship. The target rotation speed of the input shaft of the continuously variable transmission is determined based on the valve opening degree and vehicle speed, and the gear ratio of the continuously variable transmission is adjusted so that the target rotation speed matches the actual rotation speed of the input shaft. be done. In such vehicles, a single type of shift pattern is normally used to switch gears of the sub-transmission.

Problems to be Solved by the Invention However, in such conventional vehicles, when the shift lever is operated, for example, to the normal driving range (D range), the auxiliary transmission is generally fixed to the high speed gear. Yes, when the automatic shift range (S range) is operated, either the low speed gear or high speed gear of the auxiliary transmission is automatically selected based on the vehicle speed and throttle valve opening from the shift pattern. It has become so. For this reason, when a vehicle is equipped with a high-performance (high rotation, high torque) engine, when the shift lever is operated to the normal driving range (D range), the gear ratio of the entire transmission becomes small, and at low vehicle speeds, the engine It was not possible to fully demonstrate the output of the engine, and the driving force for the vehicle could not be obtained.

On the other hand, move the shift lever to automatic shift range (S range).
Although it is possible to obtain driving force for the vehicle by operating the sub-transmission, sufficient usability has not necessarily been obtained in changing the gear stage of the sub-transmission.

Means for Solving the Problems The present invention has been made against the background of the above circumstances.
The gist of this is that in a vehicle continuously variable transmission equipped with an auxiliary transmission that can be switched to two or more forward gears, the auxiliary transmission While the transmission automatically switches to one of its forward gears, a target rotational speed of the input shaft of the continuously variable transmission is determined based on the vehicle speed and the required output amount of the engine from a predetermined relationship; A control device that continuously adjusts a gear ratio so that a target rotation speed and an actual input shaft rotation speed match, the control device comprising: (1) a storage means for storing a plurality of types of gear change patterns; and (2) the vehicle. a running performance selection operation device for selecting the running performance of the
(3) A shift pattern selection means for selecting a shift pattern according to the operation of the driving performance selection operation device from among the plurality of types of shift patterns stored in the storage means.

Effects of the Invention In this manner, one of the plurality of shift patterns stored in the storage means is selected in accordance with the operation of the driveability selection operation device, and the sub-transmission is selected from this shift pattern. Since the gear stage is automatically changed, even when the shift lever is maintained in the normal driving range, the engine output can be fully exerted according to the operation of the driving performance selection operation device, and the engine output can be adjusted as needed. Sufficient driving force for the vehicle can be obtained. This is especially advantageous when the vehicle is equipped with a high-performance engine.

EXAMPLE Hereinafter, an example of the present invention will be described in detail based on the drawings.

In FIG. 2, a vehicle engine 10 is connected to an input shaft 16 of a continuously variable transmission 14 via a fluid coupling 12 with a lock-up clutch. The human power shaft 16 is provided with a variable pulley 22 whose V-groove width, that is, the hanging diameter of the transmission belt 20 is changed by a hydraulic cylinder 18 , and the output shaft 24 is provided with a variable pulley 22 whose V-groove width is changed by a hydraulic cylinder 26 . A variable pulley 28 is provided.

Therefore, the rotational force transmitted to the input shaft 16 is transmitted to the output shaft 24 via the transmission belt 20 wrapped around the variable pulleys 22 and 28, and is also transmitted to the sub-transmission 30 at the subsequent stage. The sub-transmission 30 includes a first sun gear 32
, a second sun gear 34, a ring gear 36, and the like. High speed clutch 3
8. By selectively operating the low gear brake 40 and the reverse brake 42 by a hydraulic actuator (not shown), the gear ratio R1 of the auxiliary transmission 30 is switched, or It is possible to switch between rotation and reverse rotation.

Here, in Figure 3, ρ is Z, , /Z,, ρ
2 is Z5□/Z. However, ZSI is the number of teeth of the first sun gear 32, Zs□ is the number of teeth of the second sun gear 34, and Z.

is the number of teeth of the ring gear 36. Belt type continuously variable transmission
The output shaft 24 of No. 14 constitutes an input shaft of the auxiliary transmission 30, and the carrier 44 that supports the planetary gear in the auxiliary transmission 30 constitutes an output shaft. It is the value obtained by dividing the rotation speed of the output shaft 24 by the rotation speed. The rotational force transmitted to the carrier 44 is transferred to the intermediate gear 46.
．． 48 and a final reduction gear 50, the signals are transmitted to the drive wheels 52 of the pair of vehicles.

An input shaft rotation sensor 58 and an output shaft rotation sensor 60 are provided near the variable pulleys 22 and 28 to output pulse signals SPI and SF3 having frequencies corresponding to the rotational speeds of the variable pulleys IJ22 and 28 to the controller 54. It is being

Further, a vehicle speed sensor 62 is provided near the intermediate gear 48 for outputting a noise signal S■ having a frequency corresponding to the rotational speed of the intermediate gear 48 to the controller 54. Further, a throttle sensor 64 is provided in a throttle valve provided in an intake pipe (not shown) of the engine 10, and a throttle signal Sθ representing the throttle valve opening degree θ is supplied from the throttle sensor 64 to the controller 54. . In addition, the shift lever can be used as a shift switching device.
66 is used, and the operation position sensor 68 detects the operation position of the shift lever 66.
A signal SP representing the shift operation position Psh of 66 is supplied to the controller 54. This shift lever 66 is mechanically connected to a manual pulp in the hydraulic circuit 70, and when operated to the neutral range, operates the high speed clutch 38, the low speed brake 40, and the reverse brake 42, respectively. However, when the reverse range is operated, hydraulic oil is supplied only to the hydraulic actuator that operates the reverse brake 42. Further, when the shift lever 66 is operated to the engine brake (L) range of the forward range, hydraulic oil is allowed to be supplied only to the hydraulic actuator that operates the low speed brake 40, and the low speed side Make sure the gear is maintained. In addition, when the shift lever 66 is operated to the normal drive (D drive) range of the forward range, one of the hydraulic actuators that actuates the high speed clutch 38 and the low speed brake 40 is actuated. Allow oil to be supplied. Hydraulic pressure is alternatively supplied to these hydraulic actuators from a shift valve that operates in response to the operation of a shift electromagnetic valve 72 provided in the hydraulic circuit 70.

Furthermore, the vehicle is provided with a driving performance selection switch 82 that functions as the driving performance selection operation device of this embodiment, and a signal SS indicating whether the economy push button or the power push button is pressed is sent to the controller 54. Supplied.

The hydraulic circuit 70 also supplies line hydraulic pressure regulated in accordance with the actual gear ratio of the continuously variable transmission 14 and the output torque of the engine 10 to the hydraulic cylinder 26 provided on the output shaft 24, thereby transmitting power. The tension in the belt 20 is controlled as necessary and fully. The hydraulic circuit 70 also includes a shift direction switching valve 74 with respect to the hydraulic cylinder 18 provided on the input shaft 16.
In response to the operation of the shift speed switching valve 76, hydraulic oil is supplied or discharged, and in response to the operation of the shift speed switching valve 76, the hydraulic oil inflow speed to the hydraulic cylinder 18 or the hydraulic oil discharge speed from the hydraulic cylinder 18 is changed. let

The hydraulic pump 78 is driven by the engine 10 or the like to force-feed the hydraulic oil in the oil tank 80 to the hydraulic circuit 70, and functions as a hydraulic source for the hydraulic circuit 70.

The controller 54 includes a CPU 55. ROM56, R
A so-called microcomputer including AM57, R
While utilizing the memory function of the AM57, the input signal is processed according to a program stored in advance in the ROM56, and the operation of the shift solenoid valve 72 is controlled to automatically shift the gear stage of the sub-transmission 30. The operation of the shift direction switching valve 74 and the shift speed switching valve 76 is controlled in order to change the gear ratio of the machine 14 to an optimum value. Above ROM5
6 functions as a storage means in this embodiment,
It stores the relationships shown in FIGS. 4, 5, 6, and 7, which will be described later.

Hereinafter, the main part of the operation of this embodiment will be explained according to the flowchart shown in FIG.

FIG. 1 shows a control routine for controlling the gear ratio of the entire transmission of a vehicle. First, step S1 is executed to increase the vehicle speed, the throttle valve opening θ, and the rotational speed of the input shaft 16. N in, output shaft 2
4 rotational speed N. ut, operating position P of shift lever 66
□ is read based on signals SPI, SP2, Sθ, SV, and SP. Next, step S2 is executed to determine whether the actual operating position of the shift lever 66 is in the normal driving (D) range or the engine brake (L) range.

In step S2, if it is determined that the shift lever 66 has been operated to the engine brake range, that is, the L range, step S3 is executed, so that the shift lever 66 is shifted to the low-speed gear position representing the relationship shown in FIG. 1
Data map is selected. This relationship is set so that the target rotational speed is higher than the second data map for other low speed gears so that driving force or engine braking action suitable for the L range can be obtained. Then, by executing step S4, the low speed gear stage
The target rotation speed N in is determined based on the vehicle speed V and the throttle valve opening θ from the 1 data map, and step S5 is executed, so that the input shaft 1
6 actual rotational speed N i n and the target rotational speed N
The shift direction switching valve 74 and the shift speed switching valve 76 are operated so that the speed ratio of the continuously variable transmission 14 is continuously changed so that the shift direction switching valve 74 and the shift speed switching valve 76 coincide with each other.

If it is determined in step S2 that the shift lever 66 has been operated to the normal driving range, that is, the D range, step S6 is executed to determine the operating position of the driving performance selection switch 82. If it is determined that power driving has been selected by operating the PWR push button of the driving performance selection switch 82, step S
7, the shift patterns shown in A and B in FIG. 5, for example, are selected from among the shift patterns previously stored in the ROM 56. Of the shift patterns shown in A and B, A is a shift down line used for determining the 1-2 shift, that is, the shift from a high gear to a low gear.
B indicates a shift up line used for determining the 1-2 shift, that is, the shift from a low gear to a high gear. However, in step S6, the running performance selection switch 82
If it is determined that economy driving has been selected by operating the ECO push button, step S8 is executed to select one of the shift patterns previously stored in the ROM 56, such as those shown in C and D in FIG. A shift pattern is selected. The shift patterns shown in C and D are set at a lower vehicle speed than the shift patterns shown in A and B. Note that steps S6, S7, and S8 correspond to a shift pattern selection means, since they select a shift pattern according to the operation of the driveability selection switch 82 from a plurality of types of shift patterns stored in the ROM 56.

Then, in step S9, shift control for switching the gear stage of the sub-transmission 30 is executed.

That is, from the shift pattern selected in step S7 or S8, the gear position of the sub-transmission 30 is determined based on the vehicle speed ■ and the throttle valve opening θ, and the shift solenoid valve is adjusted so that the gear position is realized. A drive signal is output to 72. As mentioned above, the shift patterns shown in C and D in FIG. When a shift pattern is selected, the downshift to a low gear is delayed, making economical driving possible, while the shift patterns shown in A and B are selected in response to the selection of power driving. If this occurs, a downshift to a low gear is performed early, allowing powerful driving with a large driving force.

Next, by executing step SIO, it is determined whether the actual gear position of the sub-transmission 30 is a high speed gear position or a low speed side gear position. If it is determined that the gear position is the high speed side, step Sll is executed and a data map for the high speed side representing the relationship shown in FIG. 6, for example, is selected from a plurality of data maps stored in the ROM 56. However, if it is determined in step SIO that the gear position of the auxiliary transmission 30 is a low speed gear position, step S12 is executed and a second data map for low speed gear positions representing the relationship shown in FIG. 7 is generated, for example. is selected. When a relationship suitable for the shift operation position and the gear position of the auxiliary transmission 30 is selected in this way, step S4 is executed to determine the vehicle speed from the data map for the high speed gear position or the second data map for the low speed gear position. ■Target rotational speed N based on and throttle valve opening θ! J is determined and step S5 is executed, whereby the shift direction switching valve 74 and the shift speed switching are performed so that the actual rotational speed N i n of the input shaft 16 and the target rotational speed N i n match. The valve 76 is operated to continuously change the speed ratio of the continuously variable transmission 14.

Regarding the data map for the high-speed gear stage, two types of lines are set in the high-speed gear range, and one of them is adopted in connection with the selection operation of the driving performance selection switch 82. In other words, when power running is selected, the two-dot chain line on the high rotation side is selected,
When economy driving is selected, the one-dot chain line on the low rotation side is selected. Therefore, when economy driving is selected, the target rotational speed N in is determined to be partially low in the high rotational speed region.

The above series of steps are repeatedly executed when the vehicle is in a running state, but when the shift lever 66 is operated in the normal running range, the running performance selection switch 82 is
In response to the selection operation, either the power driving shift pattern or the economy driving shift pattern is selected.
The gear stage of the sub-transmission 30 is changed based on this selected shift pattern. The shift pattern for economical driving places emphasis on economical driving, and changes from a high gear to a low gear and from a low gear to a high gear are performed at relatively low vehicle speeds. Therefore, when economy driving is selected by the driving performance selection switch 82, the gear ratio of the entire transmission is continuously changed in a relatively small range, allowing the vehicle to travel relatively economically. be able to. In addition, the shift pattern for power running places emphasis on the driving force of the vehicle, and the switching from a high gear to a low gear and from a low gear to a high gear is performed at relatively high vehicle speeds. Therefore, when power driving is selected by the driving performance selection switch 82, the gear ratio of the entire transmission is continuously changed over a relatively large range, giving the vehicle a powerful and powerful driving performance. It is possible to make it run.

In addition, such power driving and economy driving can be selectively selected by the driving performance selection switch 82 as necessary. Therefore, for example, if an automatic transmission range selected by the shift lever 66 is set and the automatic transmission range is selected by the shift lever 66, Compared to a system in which the sub-shift gears [30] are automatically switched according to a shift pattern, this method has the advantage of eliminating discomfort caused by the complexity of switching.

Although one embodiment of the present invention has been described above, the present invention is also applicable to other aspects.

For example, in the embodiment described above, the driveability selection switch 82
selects two types of running performance, and in connection with this selection, two types of shift patterns are alternatively selected, but it is possible to select three or more types of running performance, and in connection with this selection, three
Alternatively, the shift pattern may be selected from more than one type of shift pattern.

Further, in the above-mentioned embodiment, the sub-transmission 30 is
Although the present invention is of a type in which the gears can be selectively switched to three forward gears, it may be provided with three or more forward gears.

Further, in the continuously variable transmission 14, the transmission belt 20 is connected to the variable pulley 2.
Although the belt-type continuously variable transmission is of a type wrapped around belts 2 and 28, other types of continuously variable transmissions may be used.

Further, in the above-described embodiment, the throttle valve opening θ was used as the amount representing the required output of the engine, but the accelerator operation amount, the fuel injection amount, or the fuel injection time may also be used.

The above-mentioned embodiment is merely one embodiment of the present invention, and various modifications may be made to the present invention without departing from the spirit thereof.

[Brief explanation of drawings]

FIG. 1 is a flowchart illustrating the operation of the apparatus of FIG. FIG. 2 is a diagram showing an apparatus according to an embodiment of the present invention. FIG. 3 is a diagram showing a switching state in the sub-transmission of FIG. 2. FIG. 5 is a diagram showing a shift pattern used for automatic shifting of the auxiliary transmission in the flowchart of FIG. 1. FIG. 4, FIG. 6, and FIG. 7 are diagrams showing the relationships used to determine the target rotational speed in the flowchart of FIG. 1, respectively. 14: Continuously variable transmission 30: Sub-transmission 56: ROM (memory means) 82: Driving performance selection switch (driving performance selection operating device) Step S6. S7. S8: Shift pattern selection means Applicant: Toyota Motor Corporation Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Scope of Claims] In a vehicle equipped with a continuously variable transmission for vehicles having an auxiliary transmission that can be switched to two or more forward gears, based on the vehicle speed and the required output amount of the engine from a predetermined shift pattern, While automatically switching the auxiliary transmission to one of its forward gears, the target rotational speed of the input shaft of the continuously variable transmission is determined based on the vehicle speed and the required output amount of the engine from a predetermined relationship. , a control device that continuously adjusts the gear ratio so that the target rotation speed and the actual input shaft rotation speed match, the control device comprising: a storage means for storing a plurality of types of gear change patterns; and a control device that controls the running performance of the vehicle. and a shift pattern selection means for selecting a shift pattern according to the operation of the driveability selection operation device from a plurality of types of shift patterns stored in the storage means. A control device for a continuously variable transmission for a vehicle equipped with a characteristic sub-transmission.