JP2712485B2 - Transmission control device for automatic transmission - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for an automatic transmission having a constant-speed traveling device.

[Conventional technology]

2. Description of the Related Art Conventionally, in an automatic transmission, a gear shift unit that converts the behavior of a change lever unit by manual operation into an electric signal, receives the electric signal, operates an actuator, and changes the gear meshing state of the transmission by operating the actuator. Is disclosed. Further, in an automatic transmission, an automatic transmission having a one-way clutch that operates only at the time of driving and an overrun clutch that can cooperate with the drive coast side in order to improve shift quality such as reducing shift shock of the automatic transmission. , Control for limiting the operation range of the overrun clutch to a range where the throttle opening θ is low, that is, θ ₀ > θ, by electronic control or the like is widely used. This control will be outlined with reference to the flowchart in FIG.

Such a shift control device for an automatic transmission is controlled as follows. First, the sensors detecting the gear position P _G of the gear shift unit and the lever position P _L of the change lever unit detect the position of the gear position P _G and the lever position P _L in the current operation.
Is detected (step 33). Lever position of the change lever unit in response to signals from each sensor
P _L is the second speed, or determines whether the third speed or the fourth speed of the D range (step 34). If the lever position P _L is any of the above shift speed, gear position P _G is the first speed gear shift unit determines whether or not located in the second speed or the third speed (step 37), also, the If not the gear position, the lever position P _L determines whether a first speed (step 35). If the lever position P _L is not a first speed releases the overrun clutch (step
40), and when the lever position P _L is the first speed, gear position P _G is equal to or a first speed or the second speed (step 36). If the gear position P _G is not 1-speed or 2-speed releases the overrun clutch (step
40). Further, when the gear position P _G is first speed or second speed is controlled to operate by fastening the overrun clutch (step 47). Also, when the gear position P _G of the gear shift unit is located at the first speed, second speed or third speed, detects the throttle opening theta (step 38),
Gear position P _G is the first speed, if not located second speed or the third speed releases the overrun clutch (step
40). It is determined whether or not the detected throttle opening θ is smaller than or equal to a predetermined throttle opening θ ₀ (that is, θ ≦ θ ₀ ) (step 39). Control is performed so as to be engaged (step 47), and if it is larger, the overrun clutch is released so as not to operate (step 40).

Further, for example, a shift control device of an automatic transmission having a constant speed traveling device disclosed in Japanese Patent Application Laid-Open No. 63-186059 is disclosed. A shift control device for the automatic transmission will be described with reference to FIG. The shift control device of this automatic transmission is:
A torque converter 20 fastened to the engine output shaft 13,
The transmission gear mechanism 30 disposed on the output side of the torque converter 20, a plurality of friction fastening elements 41 to 46 for switching the power transmission path of the transmission gear mechanism 30, and hydraulic oil for the actuators of the friction fastening elements 41 to 46 A plurality of shift valves for controlling the supply and discharge of the vehicle, a constant speed traveling device configured to obtain a plurality of shift speeds in accordance with a combination of operating positions of the shift valves, and to maintain the vehicle speed at a set vehicle speed When outputting a downshift signal from the predetermined high speed stage to the predetermined low speed stage where the engine brake operates from the constant speed traveling device, the downshift during acceleration or downshift during deceleration is provided. Acceleration / deceleration determining means for determining whether
At the time of downshifting during acceleration, the gear shifts from the high gear to the low gear through a state in which the friction engagement element for the engine plate is not engaged, and at the time of downshift during deceleration, the friction engagement element for the engine brake is engaged from the high gear. And control means for switching to a low gear through a state in which the gear is changed.

Further, for example, Japanese Patent Application Laid-Open No. Sho 60-1031 discloses a travel control device for an automobile. The travel control device, in an automobile equipped with an automatic constant-speed traveling device and an automatic transmission, the automatic constant-speed traveling device has an operation signal generating unit that outputs a signal indicating that the device is operating, The automatic transmission has shift control canceling means for canceling normal shift control in response to a signal from the operation signal generating means.

[Problems to be solved by the invention]

However, in the control for limiting the operation range of the overrun clutch in the automatic transmission to a range where the throttle opening is low, the overrun clutch does not operate with a delicate throttle operation when running at a constant speed on a downhill or the like. an empty run state in the range of throttle opening theta> theta _0, when you keep the constant speed, the throttle opening is theta
_0> repeatedly state between theta and theta> theta _0, rising and falling of the engine speed, as well as be a repetition of upshifting and downshifting. In particular, in an automatic transmission equipped with a constant-speed traveling device, during operation of the constant-speed traveling device, as shown in FIG.
That is, the above-mentioned phenomenon appears remarkably, and gives the driver discomfort such as discomfort and annoyance.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-described problem, and in an automatic transmission having a constant-speed traveling device, a control is performed such that an overrun clutch is engaged during operation of the constant-speed traveling device to always operate. It is another object of the present invention to provide a shift control device for an automatic transmission that can suppress engine speed fluctuations and reduce unnecessary shifts while the vehicle is traveling at a constant speed.

[Means for solving the problem]

The present invention is configured as follows to achieve the above object. That is, the present invention provides an operation signal generating means for outputting either an operation signal or a non-operation signal of a constant speed traveling device, and an overrun clutch which receives an operation signal of the constant speed traveling device from the operation signal generating means. Means for engaging and controlling engagement of the overrun clutch only during coasting when a non-operation signal of the constant-speed traveling device is received.

[Action]

The present invention is configured as described above, and operates as follows. In other words, the shift control device of the automatic transmission receives the operation signal of the constant-speed running from the operation signal generating means and controls the transmission to operate by engaging the overrun clutch. While the vehicle is running at a constant speed, fluctuations in engine rotation during constant-speed running of the vehicle can be suppressed, and unnecessary shift operations can be reduced.

〔Example〕

Hereinafter, an embodiment of a shift control device for an automatic transmission according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a skeleton diagram of a power train that can achieve a shift control device for an automatic transmission according to the present invention. The automatic transmission 1 mainly includes friction elements such as a torque converter 2, a transmission gear mechanism 3 driven by an output of the torque converter 2, a clutch and a brake for switching a power transmission path of the transmission gear mechanism 3, that is, Forward clutch 4A, overrun clutch 4B, 3
-4 clutch 4C, reverse clutch 4D, band brake 2-4 brake 4E, and low reverse brake 4
F, and one-way clutches 5A and 5B. In this automatic transmission 1, as shown in FIG. 3, there are D, 3, 2, 1, and R ranges as travel ranges. Also, to obtain the first, second, third and fourth speeds as the D range, the first, second and third speeds as the three ranges, the first and second speeds as the two ranges, and the first and second speeds as the one range It is configured to be able to. The torque converter 2 has an output shaft 7 of the engine.
A pump 8 is connected to the engine via a case 11 and is driven by an engine, a turbine 9 rotated by the operation of the pump 8, and a stator 10 having a torque increasing action supported by the case 11. A turbine shaft 6 is fixed to the turbine 9, and the turbine shaft 6 and the output shaft 7 of the engine are configured to be connectable via a lock-up clutch 12. The output side of the transmission gear mechanism 3 is connected to an output gear 14, which is drivingly connected to left and right axles 16 and 17 via a differential gear device 15.

With reference to FIG. 3, the shift speed of the automatic transmission 1 will be described in relation to the friction elements 4A to 4F such as clutches and brakes, which are friction elements, and the operating states of the one-way clutches 5A and 5B. In the figure, a circle indicates that the vehicle is always engaged, a parenthesized circle indicates that the vehicle is engaged during driving, and a dotted circle indicates that the vehicle is engaged during coasting (coasting) in which the vehicle runs by inertia. In the table of FIG. 3, the forward clutch 4A is FWD / C, the overrun clutch 4B is OVR / C, the 3-4 clutch 4C is H / C, the reverse clutch 4D is REV / C, and the band brake is 2-4. The brake 4E is displayed as 2-4 / BAND, the low reverse brake 4F is displayed as L & R / B, the one-way clutch 5A is displayed as FWD / OWC, and the one-way clutch 5B is displayed as LOW / OWC.

As can be seen from the figure, in one range of the shift speed,
The overrun clutch 4B and the forward clutch 4A are always engaged, and the one-way clutch 5A is engaged during driving. Further, in one range, the low reverse brake 4F is engaged in the first speed, and the 2-4 brake 4E is engaged in the second speed.

In the D range (excluding the fourth speed), the third range, and the second range of the shift speed, the overrun clutch 4B is engaged during coasting, the forward clutch 4A is always engaged, and the one-way clutch 5A is engaged during driving. One-way clutch at 1st speed in D range
5B is engaged during driving, the 2-4 brake 4E is engaged in the second speed, and the 3-4 clutch 4C is engaged in the third speed. D
In the fourth speed range, the forward clutch 4A, the 2-4 brake 4E and the 3-4 clutch 4C are always engaged. Also,
In the third range, the one-way clutch 5B is engaged when driving in the first speed, the 2-4 brake 4E is engaged in the second speed, and the 3-4 clutch 4C is engaged in the third speed. In addition, in 2 ranges, 1-speed one-way clutch 5B
Is engaged during driving, and 2nd brake 4E in 2nd speed
Is concluded. In the R range, the low reverse brake 4F and the reverse clutch 4D are always engaged.

The control of the shift control device for an automatic transmission according to the present invention will be outlined with reference to the flowchart in FIG. First, the respective sensors for detecting the respective position of the lever position P _L of the gear position P _G and the change lever unit of the gear shift unit detects the position of the position and the lever position P _L of the gear position P _G at the current operation (Step 21 ). Lever position P _L is the second speed change lever unit according to the detected position signal, or D
It is determined whether or not the speed is the third speed or the fourth speed of the range (step 22). When the lever position P _L is any of the above gears, the gear position P _G of the gear shift unit is set to 1
Fast, it is determined whether or not located in the second speed or the third speed (step 23), and if not each gear position, the lever position P _L determines whether a first speed (step
twenty four). Lever position P _L is controlled by the controller so as to be inoperative by releasing the overrun clutch 4B and when not, the first speed (step 31). Lever position
If P _L is the first speed, it is determined whether the gear position P _G is the first speed or the second speed (step 25). If the gear position P _G is not 1-speed or 2-speed is likewise controlled by the controller so as to be inoperative by releasing the overrun clutch 4B (step 31). Further, when the gear position P _G is first speed or second speed is controlled by the controller to operate entered into overrun clutch 4B (step 32). Further, the gear position P _G is the first speed gear shift unit, when located in the second speed or the third speed, constant speed running device (i.e., auto cruise) whether is operating, the operation of the sensor, or the like It is detected by the signal generating means (step 26). That is, the operation signal generating means can output a signal indicating an operation state or a non-operation state of the constant speed traveling device, and receives an operation signal of the constant speed traveling device from the operation signal generating means, It is detected whether the constant-speed traveling device is currently set in the operating state or inactive. Upon receiving an operation signal from the operation signal generating means for setting the constant-speed traveling device to the operating state, the controller is controlled so that the overrun clutch 4B is engaged and the overrun clutch 4B is operated (step 32). . When a non-operation signal of the constant-speed traveling device is received from the operation signal generating means, the sensor detects the throttle opening θ (step 28). It is determined whether or not the detected throttle opening θ is not larger than the predetermined throttle opening θ ₀ (that is, θ ≦ θ ₀ ) (step 29).
If not, the controller controls the overrun clutch 4B to engage and operate (step 32).
If the detected throttle opening θ is larger than the predetermined throttle opening θ ₀ , the controller controls the overrun clutch 4B to be released and inactivated (step 31).

As described above, the shift control device for an automatic transmission according to the present invention controls the engagement state of the overrun clutch 4B by the controller, whereby the overrun clutch 4B functions in the engagement state or the non-engagement state, as shown in FIG. It is possible to control the vehicle speed and engine speed in a substantially uniform state, that is, engine speed fluctuations while the vehicle is traveling at a constant speed to a predetermined speed, and to avoid unnecessary gear shifting.

〔The invention's effect〕

The shift control device for an automatic transmission according to the present invention is configured as described above, and has the following effects. That is, the shift control device of the automatic transmission includes an operation signal generating unit that outputs either an operation signal or an inactive signal of the constant speed traveling device, and an operation signal of the constant speed traveling device from the operation signal generating unit. Means for controlling the engagement of the overrun clutch only during coasting when receiving the non-operation signal of the constant-speed traveling device, so that the function of the overrun clutch,
When the constant-speed traveling device is on, fluctuations in engine rotation during constant-speed traveling of the vehicle can be suppressed, and unnecessary shifting is not performed. A natural feeling in driving operation can be obtained without giving an unpleasant feeling.

[Brief description of the drawings]

FIG. 1 is a skeleton diagram of a power train for achieving a shift control device for an automatic transmission according to the present invention, FIG. 2 is a flowchart showing an operation state of the shift control device for an automatic transmission according to the present invention, and FIG. FIG. 4 is a table showing the operation state of friction elements in the power train shown in FIG. 4, FIG. 4 is a graph showing the relationship between time, vehicle speed and engine rotation by the shift control device for an automatic transmission according to the present invention, and FIG. FIG. 6 is a schematic diagram showing an example of a shift control device of a transmission, FIG. 6 is a flowchart showing an operation state of the shift control device of the conventional automatic transmission, and FIG. 7 is a time and vehicle speed by the shift control device of the conventional automatic transmission. 4 is a graph showing the relationship between the engine speed and the engine speed. 1 ... automatic transmission, 2 ... torque converter, 3 ... transmission gear mechanism, 4A ... forward clutch, 4B ... overrun clutch, 4C ... 3-4 clutch, 4D ... reverse clutch, 4E ... 2 -4 brake, 4F: low reverse brake, 5A, 5B: one-way clutch, 6: turbine shaft, 7: output shaft, 14: output gear.

Claims (1)

(57) [Claims] An operating signal generating means for outputting either an operation signal or a non-operating signal of a constant speed traveling device, and an overrun clutch is engaged upon receiving an operation signal of the constant speed traveling device from the operation signal generating means. Means for controlling engagement of the overrun clutch only during coasting when receiving a non-operation signal of the constant speed traveling device.