JPH0522433Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Technical field of the invention The present invention relates to an automatic transmission for a vehicle, and particularly relates to an automatic transmission for a vehicle suitable for automatically performing gear shift control in response to operation of a control lever. .

(B) Prior Art and Problems Conventionally, manual automatic transmissions for vehicles have been configured to shift to a desired gear position by the driver's clutch pedal and lever operations. For this reason, shifting operations are very troublesome when driving over long distances, and especially in large vehicles, the clutch and shift lever operations are heavy and cause fatigue.

Therefore, a mechanical automatic transmission system that achieves both easy drive and fuel efficiency was proposed (for example, Utility Model Application No. 70608/1983). This device is configured such that when a gear shift is commanded in accordance with the operation of a shift lever of a shift tower, a shift change is automatically performed by operating an actuator based on a command from a control unit. As shown in FIG. 4, this type of conventional device includes a lock-up mechanism 12, a fluid coupling 14,
The transmission is configured to be transmitted via a mechanical clutch 16 to a transmission 18 . That is, the fluid coupling 14 is provided so that the vehicle can be started without operating the clutch pedal. Furthermore, in this system, in order to reduce the cost of the system, the synchronizing mesh of the transmission 18 is removed and the detection output of the gear rotation speed sensor 20 and the detection output of the vehicle speed sensor 22 are monitored. A system was adopted in which the gear was set once synchronization was achieved. Further, in this system, in order to shorten shift time and reduce shift shock, a method was adopted in which gears were set while the mechanical clutch 16 was connected.

However, with the above device, if the engine speed is maintained high relative to the vehicle speed (because the two speeds do not match) and the lock-up mechanism is not turned on (connected) when sudden acceleration is performed after starting, etc. In a situation where the mechanical clutch is connected and the lock-up mechanism is turned off, as in the case of a shift change, there is a relative rotational speed between the input and output sides of the fluid coupling. In our case, we had a problem where torque was transmitted to the output side and surface pressure was built up on the transmission gear, making it impossible to pull out the gear.

(c) Purpose of the invention The present invention relates to control when changing gears in a vehicle using the above-mentioned transmission mechanism, and its purpose is to smoothly and quickly set gears in a situation where the lock-up mechanism is turned off. An object of the present invention is to provide an automatic transmission device for a vehicle that can perform the following functions.

(d) Structure of the invention In order to achieve the above object, the present invention has a lock-up mechanism that connects the input shaft and output shaft of a field coupling or torque converter, and the lock-up mechanism connects and disconnects the clutch in response to the operation of the operating lever. In automatic transmission systems for vehicles that perform gear shift control of the transmission and engine speed, and change gears based on the operation of the shift lever, the gear shift operation using the operation lever is performed when the lock-up mechanism is turned off while driving. In response to this operation, the engine rotation speed and gear rotation speed are monitored, and when the two rotation speeds almost match, a command is given to shift the gear to neutral, and then a command is given to turn on the lock-up mechanism. This is an automatic transmission device for a vehicle having a control means for executing gear control after the transmission is performed.

Then, when a gear shift operation is performed using the operating lever when the lock-up mechanism is turned off, if the gear is shifted to neutral when the engine rotation speed and the gear rotation speed are almost the same, the input shaft of the transmission By taking advantage of the characteristic that the transmitted torque becomes zero when the rotation of the output shaft coincides with that of the output shaft, by setting the transmission to neutral at this point, it is possible to prevent surface pressure from building up on the gears of the transmission. The gear can be disengaged, and then the lockup mechanism can be commanded on and gear set control can be performed according to conventional procedures.

(e) Embodiments of the invention Hereinafter, preferred embodiments of the invention will be described based on the drawings.

1 and 2 show the construction of a preferred embodiment of the present invention. In the figure, engine 3
0 includes a lock-up actuator 32, a fluid coupling 34, and a mechanical clutch 36.
The output shaft of the transmission 38 is connected to the rear axle via a propeller shaft 40. The engine 30 also includes a fuel injection pump 42.
The fuel injection pump 42 is provided with an accelerator actuator 44 and an accelerator fully closed sensor 46. Note that the accelerator actuator 44 is connected to an accelerator pedal 48. The mechanical clutch 36 is provided with a clutch actuator 50 and a clutch stroke sensor 52.

The transmission 38 also includes a gear set actuator 54 and a shift position detection sensor 5.
6. A gear brake mechanism 58 is provided, and the shift tower 60 is provided with a shift range detection sensor 64 that detects a shift range according to the operation of the shift lever 62, and a lever return actuator 66.

Further, the engine 30 is provided with an engine rotation speed sensor 68 that detects the rotation speed of the engine 30, and the transmission 38 is provided with a gear rotation speed sensor 70 and a vehicle speed sensor 72 that detect the rotation speed of the gears. It is being The detection outputs of the various sensors are sent to a control unit 74.
A control signal from a control unit 74 is supplied to each actuator.

The control unit 74 includes a CPU, ROM,
It is composed of a microcomputer with RAM, etc., and includes a transmission control section 76, a fluid coupling control section 78, a clutch control section 80, an accelerator control section 82, and a synchronization determination section 8.
4. It has a shift change control section 86, and each section is connected by a bus line 88. The transmission control section 76 controls the operation of the gear set actuator 54 and the gear brake mechanism 58 based on the output signal of the shift position sensor 56, and the fluid coupling control section 78 controls the operation of the lockup actuator 32. configured to control.
Further, the clutch control section 80 is configured to control the operation of the clutch actuator 50 based on the output signal of the clutch stroke sensor 52, and the accelerator control section 82 is configured to control the operation of the accelerator actuator 44. The synchronization determination unit 84 is configured to determine whether the engine rotation speed has reached a synchronization state based on the detection outputs of the gear rotation speed sensor 70 and the vehicle speed sensor 72. The shift change control section 86 includes a shift position detection sensor 56,
Accelerator fully closed sensor 46, shift range detection sensor 64, engine rotation speed sensor 68, gear rotation speed sensor 70, vehicle speed sensor 72, various buttons 9
Based on the output of 0, the gear set actuator 54 and the gear brake mechanism 58 are controlled via the transmission control unit 76, and the error lamp 92, the buzzer 94, and various relays 96 are controlled. has been done.

The present embodiment has the above-mentioned configuration, and its operation will now be explained based on the flowchart of FIG. 3.

First, when a gear shift operation is performed by operating the shift lever 62 while the lock-up actuator 32 is off,
In response to this operation, the accelerator actuator 44
and fully close the accelerator (step
100) After that, the process moves to step 102, and it is determined whether the engine rotation speed Ne detected by the engine rotation speed sensor 68 and the gear rotation speed N'g detected by the gear rotation speed sensor 70 are equal. When these two rotational speeds match, the process moves to step 104, where processing is performed to set the gear stage of the transmission 38 to neutral. That is, the transmitted torque becomes zero when the rotational speeds of the input shaft and output shaft of the fluid coupling 34 match. Therefore, if the gear stage of the transmission 38 is set to neutral in accordance with this, the gear can be pulled out without surface pressure being applied to the gear of the transmission 38, so that the neutral set can be carried out smoothly. can.

After step 104, proceed to step 106, turn on the lock-up actuator 32, and proceed to step 106.
Let's move on to processing 108. In step 108, it is determined based on the detection output of the vehicle speed sensor 72 whether vehicle speed Nv<gear rotational speed N'g. If the determination in this step is NO, the process moves to step 110 and the accelerator is fully opened by operating the accelerator actuator 44. After this, move to step 112 and Nv
It is determined whether +ΔN ₂ <N′g.

Note that ΔN ₂ is a relative rotational speed that defines release of the accelerator fully open. When the determination in step 112 is NO, the process returns to step 110 again.
If the determination is YES, the process moves to step 114.
The accelerator is fully closed by actuation of the accelerator actuator 44, and the process moves to step 118.

On the other hand, if the determination in step 108 is YES, the process moves to step 118. In this step
It is determined whether N'g<N _V +ΔN ₁ or not, and the process of step 118 is continued until this condition is satisfied.
If the answer is YES in this step, the process moves to step 120, where the gear set control of the transmission 38 is executed by operating the gear set actuator 54, and the process moves to step 122.
In step 122, the accelerator is returned to its original position by actuation of the accelerator actuator 44, and all processing in this routine is completed.

Although the above embodiment has been described as having a fluid coupling 34, this embodiment can also be applied to a case where a torque converter is mounted.

(c) Effect of the invention As explained above, according to the invention, when a gear shift operation is performed while the lockup is off, the engine rotation speed and gear rotation speed are monitored in response to the operation, and both When the rotational speeds of the engines match, a gear shift to neutral is commanded, and the lockup mechanism is then commanded to be turned on before gear shift control is executed. Even when the rotational speed is lower than the normal rotation speed, gear setting can be performed smoothly and quickly, and the excellent effect of improving operability can be obtained.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention;
FIG. 2 is a block diagram of the apparatus according to the present invention, FIG. 3 is a flowchart for explaining the operation of the apparatus according to the present invention, and FIG. 4 is an explanatory diagram of the configuration of the conventional apparatus. 30... Engine, 32... Lock-up actuator, 34... Fluid coupling, 3
6... Mechanical clutch, 38... Transmission, 42... Fuel injection pump, 44... Accelerator actuator, 50... Clutch actuator, 54... Gear set actuator,
68...Engine rotation speed sensor, 70...Gear rotation speed sensor, 72...Vehicle speed sensor, 74...
Control unit, 76... Transmission control section, 78... Fluid coupling control section, 80... Clutch control section, 82... Accelerator control section, 84... Synchro determination section, 86... Shift change control section.

Claims (1)

[Scope of utility model registration request] It has a lock-up mechanism that connects the input shaft and output shaft of a fluid coupling or torque converter, and performs intermittent control of the clutch, gear shift control of the transmission, and engine speed control in response to the operation of the operating lever, In a vehicle automatic transmission that changes gears based on the operation of the shift lever, when a gear shift operation is performed using the operation lever while the lock-up mechanism is turned off while driving, the engine rotation speed and gear rotation speed are changed in response to this operation. A vehicle characterized in that it has a control means for monitoring the rotational speeds of the two gears, instructing the shift of the gear to neutral when the rotational speeds of the two substantially match, and thereafter instructing the lock-up mechanism to be turned on, and then executing gear set control. automatic transmission.