JPH0541857B2 - - Google Patents

Description

[Detailed description of the invention]

(a) Industrial Application Field The present invention relates to a control device for an automatic transmission. (b) Prior art Electronic control in which the speed change of an automatic transmission is controlled by a hydraulic valve that is switched by a solenoid, and the on/off of the solenoid is controlled by a command signal from an electronic control device. For example, the Toyota Crown Manual (August 1988)
(Published by Toyota Motor Corporation Service Department) on the 31st. The electronic control unit controls the operation of the solenoid so that a preset shift pattern is realized based on the vehicle speed signal from the vehicle speed sensor, the throttle opening signal from the throttle opening sensor, etc. (c) Problems to be Solved by the Invention In the case of a control device that causes an automatic transmission to change gears depending on whether a solenoid is turned on or off, the solenoid must be switched during gear shifting in order to optimize the gear shifting feeling. The timing will be adjusted accordingly.
The delay time from when the start of a shift is determined to when the solenoid actually switches is set depending on the type of shift, throttle opening, vehicle speed, etc. Normally, a predetermined shift timing can be achieved by setting such a delay time. However, if the start of a certain speed is determined and another speed change is commanded before the solenoid switching is completed (for example, a 4-2 speed change is commanded during a 4-3 speed change). case), the delay time for solenoid switching will not be as set, and gear shifting performance will deteriorate. In addition, special public service 18862
Although the publication discloses a technology for adjusting the timing at which the solenoid operates according to driving conditions, it does not disclose any countermeasures when a different gear shift is commanded after the start of a gear shift has been determined. do not have. The present invention aims to solve these problems. (d) Means for Solving the Problems The present invention provides that if a different speed change is commanded after the start of a speed change is determined but before the switching of the solenoid is completed, the first speed change is The above problem is solved by controlling the delay time based on the commanded time. That is, in the control device of the present invention, as shown in FIG. 1, the shift determination means that determines whether to start a predetermined shift based on operating conditions determines the start of a shift from the A speed to the B speed. If it is determined to start shifting to C speed, which is different from B speed, within a predetermined set time after The present invention is characterized in that it includes a reference time adjustment means that causes the timing adjustment means to adjust the time at which the start of the shift to the B speed is determined as a reference. (E) Effect In the case of a normal shift from a predetermined gear to another gear, the delay time set by the timing adjustment means after the shift determination means determines the start of the shift. after which the predetermined solenoid switching takes place. This makes it possible to obtain desired shift timing. When the shift determination means commands another shift before the switching of the solenoid is completed, the delay time by the timing adjustment means is controlled using the time when the first shift is started by the reference time adjustment means as a reference time. As a result, even if another shift is performed in the middle of a shift, the shift timing as set can be achieved. (F) Embodiments Examples of the present invention will be described below with reference to FIGS. 2 to 9 of the accompanying drawings. Figure 2 shows 4 forward speeds and 1 reverse speed with overdrive.
The power transmission mechanism of the automatic transmission is shown as a skeleton diagram. This power transmission mechanism consists of a torque converter T/
An input shaft I transmits the rotational force from the engine output shaft E through C, an output shaft O transmits the driving force to the final drive device, a first planetary gear set G1, a second planetary gear set G2, a first clutch C1, a third clutch 2nd clutch C2, 3rd clutch C3, 1st brake B1, 2nd brake B2, and one-way clutch OWC
have. The first planetary gear set G1 is composed of a sun gear S1, an internal gear R1, and a carrier PC1 that supports a pinion gear P1 that meshes with both gears S1 and R1 at the same time. , carrier PC2 that supports internal gear R2 and pinion gear P2 that meshes with both gears S2 and R2 at the same time.
It is composed of. Carrier PC1 is connectable to input shaft I via clutch C2, and sun gear S1 is connectable to input shaft I via clutch C1.
It is possible to connect with Carrier PC1 is clutch C
It can also be connected to internal gear R2 via 3. Sun gear S2 is always connected to input shaft I, and internal gear R1 and carrier
PC2 is always connected to the output shaft O. Brake B1 can fix carrier PC1, and brake B2 can fix sun gear S1. One-way clutch OWC
has a structure that allows forward rotation (rotation in the same direction as the engine output shaft E) of the carrier PC1, but does not allow reverse rotation (rotation in the opposite direction to the forward rotation) (that is, a structure that acts as a brake only during reverse rotation). The above power transmission mechanism includes clutches C1, C2 and C3, and brake B1 (one-way clutch OWC).
and B2 in various combinations, each element (S1,
S2, R1, R2, PC1, and PC2) can be changed, thereby making it possible to variously change the rotational speed of the output shaft O relative to the rotational speed of the input shaft. By operating the clutches C1, C2 and C3 and the brakes B1 and B2 in combinations as shown in the table below, four forward speeds and one reverse speed can be obtained.

[Table] In the above table, O marks indicate operating clutches and brakes, α1 and α2 are the ratios of the number of teeth of sun gears S1 and S2 to the number of teeth of internal gears R1 and R2, respectively, and the gear ratio is the ratio of the rotation speed of the input shaft I to the rotation speed of the output shaft O. Furthermore, the display (OWC) below B1 indicates that the first speed can be obtained by the one-way clutch OWC even when the brake B1 is not operated. However, in the first speed in this case, it is not possible to drive from the output shaft O side (that is, the engine brake is not effective). Note that the brake B2 is constituted by a band brake, and its operation is controlled by a hydraulic servo device. The hydraulic servo device has a servo apply chamber S/ that applies hydraulic pressure in the direction of brake engagement.
A, and a servo release chamber S/R (the pressure receiving area of the servo release chamber S/R is larger than the pressure receiving area of the servo apply chamber S/A) that applies hydraulic pressure in the direction of brake release. Therefore, when hydraulic pressure is supplied to the servo apply chamber S/A, the brake B2 is engaged, but when hydraulic pressure is also supplied to the servo release chamber S/R, the brake B2 is released. FIG. 3 shows a hydraulic control device that controls the supply of hydraulic pressure to the friction elements. Note that FIG. 3 shows only the basic parts of the hydraulic circuit, and the illustration of parts other than the forward speed change related to the present invention is omitted. That is, the clutch C1 operates only when reversing, and the brake B1 also operates only when reversing and in the I range, so it has no relation to the automatic shift in the D range, and is therefore not shown.
The overall configuration of the hydraulic circuit, which is not directly related to the present invention, is similar to that described in Japanese Patent Application No. 60-222436 filed by the present applicant, for example. Line pressure is discharged by the oil pump 10 and regulated by a regulator valve (not shown), and is supplied to the oil path 14 via the manual valve 12 in the case of the forward range. The supply of the oil pressure of the oil passage 14 to the oil passage 18 is controlled by the 1-2 shift valve 16, and the supply of the oil pressure of the oil passage 18 to the oil passage 22 is controlled by the 2-3 shift valve 20. Ru. Further, the supply of the oil pressure of the oil passage 14 to the oil passage 26 is controlled by a 3-4 shift valve 24.
The oil passage 22 is connected to the clutch C2, the oil passage 18 is connected to the servo apply chamber S/A, and the oil passage 2
6 is connected to clutch C3. Also oil road 2
6 Oil passage 27 connected to servo release chamber S/R
This can be continued via the servo release timing valve 29. The servo release timing valve 29 closes the oil passage 2 when hydraulic pressure acts on the oil passage 22.
6 and the oil passage 27 are configured to communicate with each other. 1-2 shift valve 16, 2-3 shift valve 20 and 3-4 shift valve 24 are each 1-2 shift valve 16, 2-3 shift valve 20 and 3-4 shift valve 24
-2 solenoid 28, 2-3 solenoid 30, 3
-4 solenoid 32, each solenoid and valve are configured to communicate the oil passage when the solenoid is off, and to shut off the oil passage when the solenoid is turned on. The operation of the 1-2 solenoid 28, 2-3 solenoid 30 and 3-4 solenoid 32 is
As shown in the figure, it is controlled by a signal from a control device 34. The control device 34 includes a vehicle speed sensor 3
6. Signals from the throttle opening sensor 38, select position switch 40, idle switch (not shown), engine oil temperature sensor, pattern selection switch, etc. are input, and based on these signals, the control device 34 selects the 1-2 solenoid. 28, 2
-3 solenoid 30 and 3-4 solenoid 32 are turned on and off. The control device 34 is a microcomputer (MPU) and a storage device (RAM and ROM).
etc. 1-2 solenoid 28, 2-3 solenoid 30
and 3-4 solenoids 32 operate in combination as shown in FIG. As a result, hydraulic pressure is supplied to each of the predetermined friction elements as shown in the combinations in the table above, and the first, second, third, and fourth speeds are achieved. The control device 34 includes a shift determining means 34a, a timing adjusting means 34b, and a reference time adjusting means 34c. The shift determination means 34a searches for a shift pattern previously stored in a storage device based on the vehicle speed signal and the throttle opening signal.
It can be determined that a predetermined shift is required. The timing adjustment means 34b controls the delay time from when the shift determining means 34a determines the necessity of shifting until actually outputting the actuation signal to the solenoids 28, 30, and 32. Delay time for 1-2 solenoid 28 as shown in Figure 6
t ₀ and t ₁ , delay time t ₂ for 2-3 solenoid 30, delay time for 3-4 solenoid 32
t ₃ and the set time t ₄ for determining the completion of the shift are retrieved from a table stored in advance in the storage device according to the type of shift, throttle opening, vehicle speed, etc. The delay times t ₀ , t ₁ , t ₂ and t ₃ are entered in advance into the table so that desired shift timing can be obtained. The reference time adjustment means 34c adjusts the delay times t ₀ , t ₁ , t _{2 and} It has a function to set the reference time of _t3 as the first gear change judgment time. This will be discussed later. Next, the control performed by the control device 34 will be explained based on a flowchart. First, the shift point is determined as shown in FIG. In addition, in the following explanation, G ₀ indicates the gear position before shifting,
_G1 indicates the gear position after shifting. first,
It is determined whether an upshift has been commanded or not, and if an upshift is necessary, 1 is added to _G1 and the result is newly set to _G1 . If no upshift is required, proceed directly to the next step. Next, it is determined whether a downshift has been commanded, and if a downshift has been commanded, the result obtained by subtracting 1 from _G1 is newly set as _G1 . G ₁ if no downshift is commanded
remain as is. Next, the start of the shift is determined as shown in FIG. First, determine whether G ₀ = G ₁ , that is, whether the gear is not being shifted (step
102). If the gear is not being shifted, the shift point is determined (104). Then determine whether G ₁ has changed, i.e. whether a gear shift should take place (same
106). If a shift is not necessary, the process ends, and if a shift is necessary, the timer is reset (108), and then the delay times t ₀ , t ₁ , t ₂ , t ₃ and t ₄ are set. This delay time is input as a table into the storage device as described above. As a result, the timer is reset at the same time as the shift is started, and measurement of delay times t ₀ , t ₁ , t ₂ , t ₃ and t ₄ is started. If the gear shift is in progress at step 102, the shift point is determined (step 112), and then it is determined whether _G1 has changed, that is, whether the shift is continuing (step 114). If _G1 does not change, no other gear change has been commanded, so the process ends. Furthermore, when G ₁ changes, the delay times t ₀ , t ₁ , t ₂ ,
Set t ₃ and t ₄ (116). As a result, when another speed change is commanded during a speed change, the timer is not reset, and the time from the first time measurement start time to the newly set delay time is measured. The delay time from when a shift is commanded until the solenoid is activated is controlled as shown in FIG. First, it is determined whether G ₀ and G ₁ are not equal, that is, whether the gear is being changed (202). If the gear is not being changed, return immediately. If the gear is changing, 1 is added to the timer (204), and the timer is set to t _0.
Determine whether the above has been achieved (ibid. 206). If the timer is smaller than _t0 , the process directly proceeds to step 210; if the timer is greater than or equal to _t0 , the 1-2 solenoid is turned on (208) and the process proceeds to step 210. Next, in step 210, it is determined whether the timer has reached _t1 or more, and if it is smaller than _t1 , the process directly proceeds to step 214, and if it is larger than _t1 , the 1-2 solenoid is changed ( 212), proceed to step 214. Step 214 determines whether the timer is greater than t ₂ and determines whether t ₂
If it is smaller than t2, the process directly proceeds to step 218; if it is greater than _t2 , the 2-3 solenoid is changed (step 216), and the process proceeds to step 218. In step 218, it is determined whether the timer has reached _t3 or more, and
If t is smaller than ₃ , proceed directly to step 222,
If _t3 or more, change the 3-4 solenoid (step 220) and proceed to step 222. In step 222, it is determined whether the timer is greater than or equal to _t4 , and if it is less than _t4 , the process returns; if it is greater than or equal to _t4 , _G0 = _G1 is set (224) and the process returns.
Setting G ₀ = G ₁ indicates that the shift has been completed. It can be seen that by the control shown in FIG. 9, the delay times from when the shift is determined until the operating state of the solenoid is switched are determined as t ₀ , t ₁ , t ₂ , and t ₃ . Note that the delay time until the solenoid is turned on is set only for the 1-2 solenoid 28 in order to adjust the timing when the select lever is switched from the neutral range to the travel range. In the case of normal gear shifting, the 1-2 solenoid 28 switches after t ₁ hour, the 2-3 solenoid switches after t ₂ hours, and the 3-4 solenoid switches after t ₃ hours. become. However, as shown in Figure 8, if a different gear change is determined during the gear shift, the process proceeds from step 114 to step 116 and the timer is not reset and a new delay time is set, so the timer is initially The timing continues from the time when the gear shift is determined. For example, if it is determined that the 4-3 gear shift has started, the timer will immediately start counting, and after _t3 hours have elapsed, the 3-4 solenoid 32 will be switched from on to off. However, before t ₃ hours have passed, 4-2
If it is determined that a shift is necessary, the 1-2 solenoid 30 is switched from the OFF state to the ON state _t2 hours after the time when the 4-3 shift is determined. Also,
In this condition, after t ₃ hours, the 3-4 solenoid 32
also switches from on to off. As a result, the same shift timing as when the 4-2 shift is commanded from the beginning is realized. In other words, the optimal shift timing is achieved as set. The same applies to other gear changes. (G) Effects of the Invention As explained above, according to the present invention, if another shift is determined after the start of a shift is determined but before the completion of the shift, the switching of the solenoid is started from the time when the first shift is determined. Since the corresponding delay time is measured, even if a different shift is specified during a shift, the gear shift timing can be achieved as set.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the relationship between the constituent elements of the present invention;
Fig. 2 is a schematic diagram of the automatic transmission, Fig. 3 is a diagram showing the hydraulic circuit, Fig. 4 is a diagram showing the control device, Fig. 5 is a diagram showing the relationship between the combination of solenoid operations and the gear stage, Fig. 6 shows the delay time, Fig. 7 shows the control flow for determining the shift point, Fig. 8 shows the control flow for determining the shift start, and Fig. 9 shows the control flow for determining the shift timing. It is a diagram. 28...1-2 solenoid, 30...2-3 solenoid, 32...3-4 solenoid.

Claims (1)

[Scope of Claims] 1. A shift control device for an automatic transmission in which a gear position is determined according to a combination of on/off states of a plurality of solenoids, which starts a predetermined shift based on operating conditions. and a timing adjustment means that adjusts a delay time from when the shift determining means determines the start of shifting until the output of the actuation signal of the solenoid, wherein the shift determining means If it is determined to start shifting from gear A to gear B within a predetermined set time after determining the start of shifting from gear A to gear B, then when changing gears to gear C, The automatic transmission is characterized by having a reference time adjusting means for adjusting the delay time of the solenoid which is switched to the second speed by the timing adjusting means based on the time when the start of the shift from the A speed to the B speed is determined as a reference. Transmission control device.