JP2923953B2 - Control device for automatic transmission for vehicles - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an improvement in a control device for an automatic transmission for a vehicle.

2. Description of the Related Art A shift operation lever operated to select at least one of a forward travel range and a reverse travel range, and automatically switched to a forward gear or a reverse gear in response to an operation position of the shift operation lever In a vehicle equipped with an automatic transmission, the inconvenience that the automatic transmission is switched to the reverse gear due to the shift operation lever being operated to the reverse traveling range during forward traveling of the vehicle is eliminated. For this purpose, a control device having a function of prohibiting switching to the reverse gear when the vehicle speed exceeds a predetermined value is provided. For example, JP-A-60-
That is the apparatus described in Japanese Patent No. 37446.

Problems to be Solved by the Invention By the way, in reverse running of the vehicle, the shift operation lever is once operated to neutral while running backward at a relatively high vehicle speed, and then the shift operation lever is moved backward again as necessary for reverse acceleration. There is a case where it is operated to the driving range. However, in the conventional vehicle automatic transmission control device, when the vehicle speed exceeds a predetermined value, switching to the reverse gear is prohibited. Since the shift to the gear is prohibited, the operability of the vehicle during reverse running may not be sufficiently obtained.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle in which when a shift operation lever is once operated to neutral and then is operated again to a reverse traveling range during reverse traveling, It is an object of the present invention to provide a control device for an automatic transmission for a vehicle that enables the automatic transmission to be switched to a reverse gear regardless of the above.

Means for Solving the Problems To achieve the above object, the gist of the present invention is to provide a shift operation lever operated to select at least one of a forward travel range and a reverse travel range, and a shift operation lever thereof. Automatic transmission that automatically switches to a forward gear or a reverse gear in response to the operating position of the vehicle, the shift to the reverse gear is prohibited when the vehicle speed exceeds a predetermined value. (A) after the shift operation lever is once operated to the reverse travel range when the vehicle is stopped, is operated to a range other than the reverse travel range in the non-stop state, and then is operated again to the reverse travel range. A reverse detection means for detecting that the vehicle is in a reverse traveling state based on the detection, and (b) when the reverse traveling state is detected, Reverse travel permitting means for permitting the shift operation lever to switch to the reverse gear in response to an operation to the reverse travel range.

In this way, the shift operation lever is once operated to the reverse travel range while the vehicle is stopped, and then operated to a range other than the reverse travel range in the non-stop state, and then operated again to the reverse travel range. When it is detected that the vehicle is in the reverse running state based on the fact that the vehicle is in the reverse running state, the shift to the reverse gear is permitted in response to the operation of the shift operation lever in the reverse running range. During reverse running when the vehicle speed exceeds a certain value, the automatic transmission is switched to the reverse gear even if the shift operation lever is once operated to neutral and then again to the reverse running range. Therefore, the determination accuracy (reliability) of the driver's backward traveling operation is enhanced, and the operability of the vehicle during backward traveling is sufficiently obtained.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 shows a mobile transmission 10 provided in a vehicle. The output of the engine not shown is a torque converter,
The power is transmitted to the input shaft 12 of the automatic transmission 10 via a clutch such as a fluid coupling or an electromagnetic clutch. The automatic transmission 10 changes the speed of rotation of the input shaft 12 and outputs the rotation from the output shaft 14 to drive wheels via an overdrive unit and a differential gear device (not shown). The automatic transmission 10
A first planetary gear unit 16 including a sun gear 16s, a first ring gear 16r, a first planetary gear 16p meshing with the sun gear 16s, and a first carrier 16c rotatably supporting the first planetary gear 16p;
A second planetary gear set 18 including a second sun gear 18s, a second ring gear 18r, a second planetary gear 18p meshing with them, and a second carrier 18c rotatably supporting the second planetary gear 18p.
The first sun gear 16c and the second sun gear 18s are respectively fixed to both ends of a sleeve shaft 20 through which the output shaft 14 is vertically passed. Further, the automatic transmission 10 includes an input shaft 12 and the first clutch C ₁ selectively connecting the first ring gear 16r, the input shaft 12 and the second clutch C ₂ selectively connecting the sleeve shaft 20 When a first brake B ₁ for the selectively nonrotatably by engaging the sleeve shaft 20 to the stationary housing 22 is selectively engaged with the sleeve shaft 20 to the stationary housing 22 a one-way clutch F ₁ and second brake B ₂ for preventing rotation in one direction,
The third brake B ₃ for a selectively nonrotatably by engaging the second carrier 18c of the stationary housing 22,
A one-way clutch F ₂ for preventing rotation in one direction of the second carrier 18c is provided. The first clutch
C ₁ , second clutch C ₂ , first brake B ₁ , second brake
B ₂ and the third brake B ₃ are friction engagement devices that are differentially actuated by hydraulic pressure, and when any of them is selectively differentially actuated, the automatic transmission 10 reverses as shown in FIG. The gear can be switched to a desired one of a gear, a first gear, a second gear, and a third gear.

FIG. 4 is a diagram showing a portion related to establishing a reverse gear in a hydraulic circuit for controlling the operation of the friction engagement device, and a main part of a control circuit for executing control for inhibiting the reverse gear. And is shown briefly. In the figure, P range,
A shift operation lever 26 operated to any one of the R range, N range, D range, 2 range, and L range and a manual valve 28 are operatively connected to each other.
There when operated to the R-range, so that the oil pressure for establishing the reverse gear is outputted from the manual valve 28 to the second clutch C ₂ and the third block B _3. The second clutch C ₂ and the third brake B ₃ and the manual valve 28 are connected to an oil passage extending from near the output port of the manual valve 28.
32 are connected in parallel. A blocking valve 34 for preventing the reverse gear from being established is interposed in the oil passage 32.

The blocking valve 34 is a spool valve having a switching function,
Third first position and the third brake B ₃ and manual to prevent communication between the valve 28 and the third brake B ₃ the spool is caused to position the second position to drain valve for the brake B ₃ communicates with the manual valve 28 Element 36 and this spool valve element 36
To a second position. The spring 38 side of the spool valve element 36 on the end face on the opposite side, has been allowed to act through a pilot hydraulic P _p is aperture stop 40, so that the downstream side of the diaphragm 40 is pressurized discharge by solenoid valve 42 ing. Therefore, when the electromagnetic valve 42 is closed by being de-energized, as shown in FIG. 4, since Pirotto pressure P _p is allowed to act on spool valve element 36, the spool valve element 36 is spring 38 Is located at the first position against the urging force. Thus, establishment of the reverse gear is allowed. However, when the solenoid valve 42 is opened by being excited, the downstream side of the throttle 40 is exhausted, and the spool valve element 36 is moved to the second position in accordance with the biasing force of the spring 38. Thus, the establishment of the reverse gear is prevented.

At the base end of the shift operation lever 26, there is provided a shift position sensor 46 for detecting the operation position of the shift operation lever 26 and outputting an operation position signal SS to the controller 44. A vehicle speed sensor 48 that detects the rotation speed of the output shaft 14 and outputs a vehicle speed signal SV to the controller 44 is provided near the output shaft 14. The vehicle speed sensor 48 is provided with a plurality of outer teeth and rotates with the output shaft 14, and is provided in the vicinity of the outer periphery of the rotator to detect the passage of the outer teeth, thereby detecting the rotation speed of the output shaft 14. And a pickup which outputs a pulse signal having a frequency corresponding to the speed signal SV as a speed signal SV, so that the vehicle speed V obtained by the controller 44 from the speed signal SV has the same positive sign regardless of whether the vehicle is traveling forward or backward. Has become. Above controller 44
Is configured by a microcomputer including a CPU, a ROM, and a RAM.The CPU processes an input signal according to a program stored in a ROM in advance while using a primary storage function of the RAM, and drives the solenoid valve 42. Output a driving signal for

FIG. 1 shows a main part of the operation of the controller 44. Note that the initial content of the flag F has been reset to “0”. In the figure, at step S1, whether actual or vehicle speed V has reached a previously fixed criterion value greater than or equal _to V ₀ of value determined is determined. This criterion value V ₀ is a relatively small value indicating the lower limit of the vehicle speed range in which the shift to the reverse gear is prevented during forward running of the vehicle.

In the stopped state of the vehicle or the low-speed running state lower than the criterion value V _{0, the} actual vehicle speed V is still determined to be lower than the criterion value V ₀ in step S 1, so that step S 2
It is determined based on the operation position signal SS whether or not the shift operation lever 26 is operated to the R (reverse running) range. When the shift operation lever 26 is operated to a range other than the R range, the determination in step S2 is denied, so that the content of the flag F is reset to “0” in step S3, and The well-known shifting operation of the automatic transmission 10 is performed according to a previously stored shift diagram and based on the vehicle speed V and the throttle valve opening. Also, in step S2, the shift operation lever
If it is determined that 26 has been operated to the R (reverse running) range, the content of the flag F is set to "1" in step S5, and the solenoid valve 42 is de-energized in step S6. As a result, the spool valve element 36 of the blocking valve 34 is moved to the first position. Thus, the reverse gear of the automatic transmission 10 is established in response to the operation of the shift operation lever 26 to the R (reverse traveling) range. Note that the flag F
Is "1", it means that the shift operation lever 26 has been operated to the R range in a state where the vehicle is in a stopped state or a state in which the vehicle is almost stopped. Represents the reverse running state. Therefore, in the present embodiment, steps S1 and S2 correspond to reverse detection means for detecting the reverse running state of the vehicle.

In the running state of the determination reference value greater than or equal _to V ₀ of the vehicle,
Since the determination in step S1 is affirmative, step S7
In, it is determined whether or not the shift operation lever 26 is operated to the R range. If the shift operation lever 26 is operated to a range other than the R range, such as a forward range or a neutral range, the above-described step S7
Is denied, a normal automatic shift operation is performed in step S4.

During operation of the vehicle as described above, the shift operation lever
If 26 has been operated to the R range, the determination in step S7 is affirmative, and it is determined in subsequent step S8 whether the content of the flag F is "1". This step
If it is determined in S8 that the content of the flag F is not “1”, the shift operation lever 26 is set to R during forward running.
Since this is the case where the operation was mistakenly performed to the range, step S9
Is executed, the electromagnetic valve 42 is opened. Therefore, the spool valve element 36 of the blocking valve 34 is moved to the second position, the third brake B ₃ is drained, switching to the reverse gear is prevented. But the above steps
If it is determined in S8 that the content of the flag F is "1", the shift operation lever 26 is set to R during reverse running.
Since the operation is again performed to the range, steps S5 and subsequent steps are executed, and the switching to the reverse gear is allowed. In the present embodiment, the above steps S1, S6, S7, S8
And the like correspond to reverse traveling permission means that permits switching to the reverse gear in response to the operation of the shift operation lever 26 to the R range when the reverse traveling state is detected.

As described above, according to the present embodiment, the vehicle is in the reverse running state based on the fact that the shift operation lever 26 is once operated to the R range and then operated to the R range while the vehicle is almost stopped. Is detected, it is permitted to switch to the reverse gear in response to the operation of the shift operation lever 26 to the R range. Therefore, during reverse traveling when the vehicle speed exceeds a certain value, the shift operation lever Even when 26 is once operated to the N range and then to the R range again, the automatic transmission 10 is switched to the reverse gear. Therefore, the determination system (reliability) of the driver's backward traveling operation is enhanced, and the operability of the vehicle during backward traveling is sufficiently obtained.

As mentioned above, although one Example of this invention was described based on drawing, this invention is applied also in another aspect.

For example, the blocking valve 34 in the above-described embodiment
Although C ₂ and the third brake B ₃ was prevented switching to the reverse gear by drainage, the second clutch
It may prevent switching to the reverse gear by drainage of C ₂ or third brake B _3.

Further, the automatic transmission 10 of the illustrated embodiments, but was of the type that is switched to the reverse gear by engaging the two engagement device C ₂ and B _3, 1 or more than two It may be of a type that can be switched to the reverse gear by engaging the engagement device.

Also, the automatic transmission 10 of the above-described embodiment is a planetary gear type stepped transmission, but is constituted by a continuously variable transmission with an automatic forward / reverse switching device, a synchronous meshing transmission equipped with a shift actuator, and the like. You may. In short, shift operation lever
It is sufficient if the automatic transmission is of a type that can be automatically switched to the forward gear or the reverse gear in response to the 26 operating positions.

Further, although the microcomputer is used in the forward embodiment, the prevention of switching of the reverse gear may be determined by a hard logic circuit that executes the same logical determination as in FIG. 1, or is represented by oil pressure. A hydraulic circuit that makes a logical decision based on a signal may be used.

The above is merely an example of the present invention, and the present invention can be variously modified without departing from the spirit thereof.

[Brief description of the drawings]

FIG. 1 is a flowchart for explaining the main part of the operation of the embodiment of FIG. FIG. 2 is a skeleton view showing the configuration of the automatic transmission used in the embodiment of FIG. FIG.
3 is a table showing gears obtained by a combination of operations of the friction engagement device of the automatic transmission of FIG. 2; FIG. 4 is a diagram showing a configuration of a control circuit according to one embodiment of the present invention, and is a diagram showing a hydraulic circuit and a main part of the control circuit. 10: Automatic transmission 26: Shift operation lever

Claims (1)

(57) [Claims] A shift operating lever operated to select at least one of a forward running range and a reverse running range, and automatically shifting to a forward gear or a reverse gear in response to an operating position of the shift operating lever. A control device of a type having a switchable automatic transmission, wherein when the vehicle speed exceeds a predetermined value, switching to the reverse gear is prohibited, and the shift operation lever is operated when the vehicle is stopped. The reverse detection that detects that the vehicle is in the reverse traveling state based on the fact that the vehicle has been operated in the non-reverse traveling range in a non-stop state after being once operated in the reverse traveling range, and then operated again in the reverse traveling range. Means for switching to the reverse gear in response to operation of the shift operation lever to a reverse travel range when a reverse travel state is detected. Control apparatus for a vehicular automatic transmission which comprises a reverse running permission means for permitting Rukoto, the.