JPS62171554A - Change gear controlling method for automatic transmission - Google Patents

Abstract

PURPOSE:To reduce any change gear shock, by preparing such a procedure as setting previously either one of change gear parts stated below in the condition of a change gear stage stated below when it is detected that the next change gear pattern is a change gear pattern toward a certain change gear stage obtained by making gear- change of the first and second change gear parts simultaneously from the stop position. CONSTITUTION:In an automatic transmission including the first/second change gear parts, sometimes it can be detected whether the next change gear pattern becomes the pattern for a certain change gear stage or not, which should be got through gear- changing the first/second change gear parts at the same time. For example, a case of a button or a lever being operated previously for the purpose of indicating the travel fixed at the second speed stage or the fourth speed stage, corresponds to the matter described above. When this matter is detected, if either of the first/second change gear parts is set previously so as to be in said change gear stage condition, the change gear indication given by an actual driver, can be satisfied by only making gear change due to changeover of the other change gear, part, and consequently, the change gear shock can be reduced to be extremely slight.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application J] The present invention relates to a speed change control method for an automatic transmission, and in particular to a first transmission section and a second transmission section that independently and automatically change gear stages. This invention relates to an improvement in a speed change control method for an automatic transmission in which multi-speed shifting is achieved by simultaneously or alternately shifting at least the first transmission section and the second transmission section. Prior Art 1 With the rapid spread of automatic transmissions for vehicles in recent years, a first gear that can automatically switch gears in relation to vehicle speed, throttle opening, etc. is mainly intended to improve fuel efficiency. Many models have been adopted in which a so-called overdrive device η with a gear ratio of 1 or less is attached in series between the second gear and the 12th gear. (by simultaneously or alternately synchronizing the gear shift in the shallow part and shifting the first gear part with a relatively large gear V ratio and the second gear part with a relatively small gear ratio) , for example, Fig. 3A
There is also already known a device in which a multi-stage speed change of six forward speeds is achieved by performing the speed change control as shown in the section (for example, Japanese Patent Application Laid-Open No. 57-37140). By doing so, it is possible to easily realize multi-speed shifting and obtain many advantages such as improved fuel efficiency, improved power performance, and reduced burden on the frictional engagement device. On the other hand, some automatic transmission units u1 are designed to allow fixed running at a specific gear position, for example, to allow more stable running at the top of a mountain. ('R, the problem that Ming tries to solve] However,
In the above-mentioned automatic transmission system, for example, if the second gear shown in Fig. 3 is selected as the specific gear for fixed travel (the advantages of selecting the second gear as the specific gear) (for example, see the patent application filed by the same applicant on December 20, 1985), if the first and second gears are set to different states in the neutral range, then from the neutral range When shifting to the drive range, the normal shift of the first transmission to the so-called first gear and the second gear shift (a high gear shift) are performed at the same time, and depending on the timing, there may be a large shift at the same time as the shift. There is a problem that shift shock may occur.Also, this type of problem is caused by, for example, the first gear being a so-called extra low gear, and engagement starts from the second gear when the drive range is shifted from the neutral range. The same problem also occurs in automatic transmissions configured such that Even if the shift pattern is one in which the gear is directly shifted from (or neutral range) to a gear that is achieved by simultaneously shifting the first and second transmission sections, an automatic shift that can do this with a small shock is possible. 5! It is an object of the present invention to provide a speed change control method for a machine. [Means for solving the problems]
Shifting (an automatic transmission comprising at least a main gear shifting section and a second shifting section, and achieving multi-speed shifting by simultaneously or alternately shifting the first shifting section and the second shifting section "a") In the shift control method, as shown in FIG. 1, the next shift pattern starts from the stop position to the first
a step of detecting whether or not the shift pattern is a shift pattern to a gear stage achieved by simultaneously shifting the second shift-like portion;
, the 22nd speed achieves the above object by including the steps of placing either one of the gears in the relevant gear state in advance. [Function] In an automatic transmission in which the first and second gear shift sections are shifted to 1, the next shift pattern is 6. It
In some cases, it may be necessary to detect whether or not the shift pattern to the gear stage is achieved by simultaneously shifting the gears. For example, this is the case when a button or lever for instructing fixed running in the second gear, d-speed, or fourth gear has been operated in advance. Further, as described above, automatic gear shifting in which engagement is started from the second gear by drive range shift (in case of absence, it is possible to detect the gear shifting pattern by shifting to the neutral range). In this case, when such a detection is made,
Since one of the first and second transmissions is placed in the corresponding gear state in advance, when the driver actually issues a shift instruction, the other transmission only needs to switch. This makes it possible to keep shift shock to an extremely low level. [Example] Hereinafter, an example of the present invention will be described in detail based on the drawings. FIG. 2 is a schematic skeleton diagram showing the gear 11/1 configuration of the FF (front engine/front drive) automatic transmission 1 to which the present invention is applied. This automatic transmission 1 is
A torque converter 12 and a transmission section 14 are provided coaxially with respect to the separate space 9. The transmission section 14 includes a first transmission section 16 and a second transmission section 18 connected in series to the output shaft of the first transmission section 16. The first transmission section 16 is an underdrive device here and has three forward speeds, and the second transmission section 18 is an overdrive device here and has a low speed speed with a reduction ratio of 1 and a high speed speed with an overdrive. It has two forward stages. 1st change 3! ! The machine part 16 includes a common sun gear 161, ring gears 162a, 162b, 1 planetary pinion 1
64a, 164b, and carrier 166a. Two rows of planetary teeth 1 on the front side and rear side consisting of 166b
equipped with clutches C1, C2, and brakes 8, respectively.
%, B 2 , B 3 , and one-way clutch F1. F
The rotation is controlled by 2. On the other hand, the second transmission separate section 18 includes a sun gear 181, a link gear 182, a planetary pinion 184, and a carrier 1.
86, and its rotation is controlled by a clutch Co s brake B o and a one-way clutch Fo. Since the specific coupling structure of the first transmission section 16 and the second transmission section 18 is well known, a detailed explanation thereof will be omitted and will only be shown as a skeleton diagram in FIG. In addition, in achieving each gear stage in the drive range, each frictional engagement device such as a brake and a clutch is controlled as shown in FIG. 3. Next, FIG. 4 shows an overall outline of the automatic transmission for a vehicle according to this embodiment. The first gear shift section 16 and the second shift section 16 of the shift section 14
The transmission section 18 is controlled by the computer 60 driving and controlling the electromagnetic solenoid valves 81 to S4 of the hydraulic control circuit 40, respectively. The computer 60 includes a strotzl opening signal from a throttle opening sensor 42 that indicates the load condition of +[]9, and a speed sensor 44 that detects the output shaft rotational speed of the automatic transmission.
, a shift position signal from the shift position sensor 46 that detects the shift position such as drive range, S range, or left range, fuel efficiency m? 52 type running anti-running force performance m? 52Ij1 A slam select signal from the slam select switch 48 that selects running, a cooling water temperature signal from the engine water temperature sensor 50 that detects the cold water temperature of the engine 9, a brake signal from the brake switch 52 that detects whether the foot brake is on or off, and A fixed travel selection signal from a manual selection switch 54 for selecting a gear for fixed travel is inputted, and these signals determine the gear for automatic transmission based on a predetermined variable speed diagram. are doing. Next, the operation of this *embodiment will be explained using FIG. First, in steps 202 to 208, read the output shaft rotational speed No., throttle opening degree θ, shift position position, and pattern select switch position of the automatic transmission. In step 210, it is determined whether the vehicle is currently in the stop range (neutral range or parking range). If YES, it is determined whether or not the manual selection switch 54 is instructing 2nd speed fixed running. If the 2nd speed fixed running instruction has not been issued, it is reset as is, but if the 2nd gear fixed running instruction has been issued, the process proceeds to step 214, where the brake Bo supply command is issued and the 2nd gear shift compensation is performed. The portion 18 is brought into the second gear engagement state in advance. On the other hand, if it is determined in step 210 that it is not in the stop range position, it is determined in step 216 whether or not it is in the reverse range, and if it is determined that it is in the reverse range, it is reset as is, but if the answer is NO, In other words, when it is determined that the shift range is the drive range, the second range, or the first range, the shift point is set according to the position of the shift range and the selection position of the pattern select switch 48. After that, if there is a shift determination in step 220, step 22
At step 2, a gear change output is performed. FIG. 6 shows a speed change transient characteristic diagram. The solid line is the characteristic according to the above embodiment. In the figure, the broken line represents the torque characteristic in the conventional case, that is, when the second shift butt is in the low state in the stop range. Now, if a shift is made from the neutral range to the drive range, for example, the brake Bo
When the supply of working oil pressure to the clutch C1 is delayed compared to the supply of working oil pressure to the clutch C1, the clutch C1 is first engaged and the first gear state is established. The shift shock at this time is quite large because the gear ratio is large. After that, the brake BO is engaged, so that a so-called upshift from the first gear to the second gear occurs, and a second shift shock occurs here. According to the above embodiment, when it is detected that the second speed fixed pattern is selected, hydraulic pressure is already supplied to the brake 8o in the neutral (parking) range and the brake 8o is in the engaged state. Therefore, when shifting from the neutral range to the drive range, the gear shift is performed only by supplying the clutch C1. In this case, since the shift is to the second gear, the gear ratio is smaller than the shift to the first gear, and the shock is correspondingly smaller. In the above embodiment, the hydraulic pressure is supplied to the brake Bo in advance depending on whether or not the manual selection switch 54 fixed to 2nd speed is pressed, but the present invention is not limited to such an example. In other words, it is a regular meeting in which it is possible to detect that the next shift pattern is a shift pattern from the stop range to a gear position achieved by simultaneously shifting the first and second transmission sections. Applicable to Effects of the Invention As explained above, according to the present invention, even when shifting from a stop position to a gear stage achieved by simultaneously shifting the first and second transmission sections, the shift speed is extremely small. An excellent effect can be obtained in that this can be done with a small shift shock.

[Brief explanation of drawings]

FIG. 1 is a flow chart showing the gist of the present invention, and FIG. 2 is a skeleton diagram showing a transmission section of a vehicle automatic transmission to which the automatic transmission shift control method according to the present invention is applied.
FIG. 3 is a diagram showing the engagement and combination of the eight frictional engagement elements for shifting each gear stage to 10, FIG. 4 is a general block diagram, and FIG. 5 is a diagram showing the control routine. The flowchart shown in FIG. 6 is a diagram similarly showing the speed change transient characteristics. 16...First transmission section, 18...Second transmission section, 54...Manual selection switch, B...Brake, C1...Clutch.

Claims (1)

[Claims] (1) By providing at least a first transmission section and a second transmission section capable of independently and automatically switching gears, and shifting the first transmission section and the second transmission section simultaneously or alternately. In a shift control method for an automatic transmission that achieves multi-speed shifting, the next shift pattern is from a stop position to a shift stage that is achieved by simultaneously shifting the first and second transmission sections. a step of detecting whether or not the shift pattern is the first shift pattern;
A method for controlling a shift in an automatic transmission, the method comprising the step of: placing one of the second transmission sections in the gear position state in advance.