JP7398180B2 - vehicle system - Google Patents

Description

The present invention relates to a type of vehicle system equipped with a differential lock function.

An example of a vehicle system is one described in Patent Document 1.
The vehicle system described in this document is equipped with a transfer that receives the driving force output from the engine and shifted by the transmission, and uses the function of this transfer to transmit the driving force to the front and rear wheels. It is possible to switch to 2WD, which transmits power only to the front wheels. Further, the transfer includes a differential device (center differential), and when the driver operates a predetermined switch, the differential device can be selectively switched to either a differential lock state or a unlocked state. It is considered configurable.

However, in the prior art, when a predetermined switch is operated, the differential gear is simply set to the differential lock state, and the transmission is not actively controlled at this time. For this reason, when an automatic transmission is used as a transmission, the differential lock may occur at a timing when the automatic transmission is not in the lowest forward gear range or the reverse gear range, or the automatic transmission may change gears while the differential is locked. There is a possibility that the action will be taken. Since it is preferable to rotate the wheels with high torque when setting the differential lock state, it is desirable to appropriately eliminate the above-mentioned concerns.
Further, in the conventional technology, since the differential lock state can be set regardless of the vehicle speed, there is a possibility that the differential lock state is set in a high speed range, making it difficult to drive the vehicle.

Japanese Patent Application Publication No. 08-108768

The present invention was devised under the above-mentioned circumstances, and provides a vehicle system that can appropriately prevent, by simple means, the differential lock state from being set at an inappropriate timing. That is the issue.

In order to solve the above problems, the present invention takes the following technical measures.

A vehicle system provided by the present invention includes a differential device configured to transmit driving force received from an engine via a transmission to an axle side and to be able to switch between a differential lock state and a differential lock release state; A vehicle system comprising: an operation means for selecting whether to set the differential device to a differential lock state or a differential lock release state; and a controller capable of determining a shift range of the transmission and a vehicle speed. In this case, when an operation is performed to set the differential device from a differential lock release state to a differential lock state using the operating means, the controller causes the transmission to shift to the lowest forward gear range or the reverse gear range. It is determined whether a first condition, which is a range, and a second condition, which is a vehicle speed being equal to or less than a predetermined speed, are satisfied, and, on the condition that the first and second conditions are satisfied, It is characterized in that it is configured to perform an operation of switching the differential gear to a differential lock state, and otherwise perform control not to switch the differential gear to the differential lock state.

According to the above-described configuration of the present invention, the following effects can be obtained.
That is, in the present invention, the control of a predetermined controller intervenes when setting the change to the differential lock state, and when the transmission is not in the lowest forward shift range or reverse shift range, the differential lock state is switched to the differential lock state. Setting is not allowed. Therefore, it is ensured that the wheels are rotated with high torque during the differential lock state. Also, when the vehicle speed is in a high speed range exceeding a predetermined speed, the differential lock state cannot be set. Therefore, when the vehicle is traveling at high speed, the differential lock state is set and the possibility that the vehicle becomes difficult to operate is appropriately resolved.

Other features and advantages of the present invention will become more apparent from the following description of embodiments of the invention with reference to the accompanying drawings.

FIG. 1 is an explanatory diagram schematically showing an example of a vehicle system according to the present invention. 2 is a flowchart illustrating an example of an operation processing procedure executed in the vehicle system of FIG. 1. FIG. FIG. 3 is an explanatory diagram schematically showing another example of the vehicle system according to the present invention. 4 is a flowchart showing an example of an operation processing procedure executed in the vehicle system of FIG. 3. FIG.

Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

The vehicle system A shown in FIG. ), a controller 6 (integrated ECU), and a sub-controller 6A (meter ECU). Reference numerals 9a and 9b indicate front wheels and rear wheels, respectively, and reference numerals 90a and 90b indicate front and rear axles.

In this vehicle system A, the output of an engine 1 is input to a belt type continuously variable transmission 3 via a torque converter 2, and after being changed in speed by the belt type continuously variable transmission 3, it reaches a transfer 4. The transfer 4 is capable of switching between a 4WD mode in which driving force is transmitted to both the front and rear differentials 5A and 5B, and a 2WD mode in which driving force is transmitted to only one of them. The rear differential device 5B can be switched between a differential lock state in which no difference in rotation is caused between the left and right rear wheels 9b, and a differential lock release state (differential lock free) in which a difference in rotation is caused. This switching setting is performed by operating the VSV 70 (vacuum switching valve: a switching valve that operates using negative pressure).

The sub-controller 6A (meter ECU) is a controller in charge of controlling the meter on the instrument panel and various devices installed around it, and includes a manual differential lock setting switch 71 and a 2WD/4WD selector switch 72. Receive signals from. This sub-controller 6A is responsible for lighting control of the differential lock lamp 73 to notify whether or not the differential lock state is established.

The controller 6 (integrated ECU) essentially controls the operation of various parts throughout the vehicle, such as drive control of the engine 1 and operation control of the belt-type continuously variable transmission 3, and performs data processing. In addition to the sub-controller 6A, a vehicle speed sensor 74 and a VSC 75 (Vehicle Stability Control) are also connected. This controller 6
When setting the rear differential gear 5B to the differential lock state, information regarding the shift range of the belt type continuously variable transmission 3, the 2WD or 4WD detection signal received from the oil pressure sensor 76 of the transfer 4, and the vehicle speed sensor are used. It is configured to execute control as described later based on signals from 74 and the like.

Next, an example of the operation processing procedure of the vehicle system A described above will be explained with reference to the flowchart shown in FIG. 2.

First, when the differential lock setting switch 71 is operated and a selection is made to perform a differential lock, this fact is recognized in the sub-controller 6A, and data is transmitted from the sub-controller 6A to the controller 6, which is received. The controller 6 also recognizes the above (S1: YES, S2, S3). Then, the controller 6 determines whether the vehicle is set to the 4WD mode based on the setting state of the 2WD/4WD changeover switch 72 and the signal from the oil pressure sensor 76 (S4, S5). In such a determination, if the mode is not 4WD mode but 2WD mode, the differential lock lamp 73 is not lit and the differential lock state is not set (S4: NO, S9, S10).

Unlike the above, when the vehicle is in the 4WD mode, the shift range of the belt type continuously variable transmission 3 is determined (S4: YES, S5: YES, S6). In this judgment, if the shift range is the lowest forward range (Low) or the reverse range (R range), then it is further judged whether the vehicle speed is below a predetermined value (S6: YES). , S7). In this case, if the vehicle speed is below a predetermined value, the controller 6 operates the VSV 70 and puts the rear differential gear 5B into a differential lock state (S7: YES, S8). Additionally, in conjunction with this, the differential lock lamp 73 is turned on. Further, data communication is performed to the VSC 75 indicating that the differential lock state is established, so that the VSC 75 is not activated when the differential lock state is set.
If even one of the conditions in steps S4 to S7 described above is not satisfied, the differential lock lamp 73 is turned off and the differential lock state is not set, as shown in steps S9 and S10.

Although omitted in the flowchart, preferably, while the differential lock state is being set, the controller 6 maintains the shift range of the belt type continuously variable transmission 3 at the lowest or reverse range, and also maintains the belt type continuously variable transmission 3 in the lowest or reverse range. It is configured to perform control to maximize the reduction ratio so that the output torque from the continuously variable transmission 3 is maximized.

According to the above-mentioned operation control, if the shift range of the belt type continuously variable transmission 3 is not the lowest forward or reverse range, the differential lock state cannot be set, and the shift range must be in one of these ranges. For example, the differential lock state is not set. Therefore, insufficient torque is prevented when the differential lock state is set. Further, even when the vehicle speed is in a high speed range exceeding a predetermined speed, the differential lock state cannot be set, and the differential lock state is set at low speeds below the predetermined speed. This prevents the differential lock state from being set while the vehicle is traveling at high speed, which makes it difficult to operate the vehicle.
In this embodiment, since the controller 6 as an integrated ECU is used for control when setting the differential lock state, there is no need to separately use a dedicated controller, which is reasonable.

FIG. 3 shows another embodiment of the invention. In the figure, elements that are the same or similar to those in the embodiment described above are designated by the same reference numerals as in the embodiment described above, and redundant explanation will be omitted.

In the vehicle system Aa shown in FIG. 3, a manual transmission 3A is drivingly connected to the engine 1 via a clutch 2A. Corresponding to this, a sensor 79 is provided to detect which gear range (gear stage) the manual transmission 3A is in, and its signal is transmitted to the controller 6.

In the vehicle system Aa of this embodiment, an operation process as shown in the flowchart shown in FIG. 4, for example, is performed. Here, in the flowchart of FIG. 4, the same steps as those in the flowchart of FIG. 3 are given the same numbers.
In the operation processing procedure shown in FIG. 4, step S6A is different from the operation processing procedure shown in FIG. In step S6A, the controller 6 determines whether the gear position (shift range) of the manual transmission 3A is the lowest 1st or reverse gear position based on the signal from the sensor 79, and if so. If there is, the process moves to the next step S7. If not, the differential lock lamp 73 is not lit and the differential lock state is not set (S6A: NO, S9, S10)
In this embodiment, a manual transmission 3A is used as the transmission, but the same effects as described in the previous embodiment can be obtained.

The present invention is not limited to the content of the embodiments described above. The specific configuration of each part of the vehicle system according to the present invention can be modified in various ways within the intended scope of the present invention.
Although it is preferable to use an integrated ECU as the controller in the present invention, it is also possible to use a different controller.

A, Aa Vehicle system 3 Belt type continuously variable transmission (transmission)
3A manual transmission (transmission)
5B Rear differential device (differential device)
6 Controller (integrated ECU)
71 Differential lock setting switch (operation means)

Claims (1)

a differential device configured to transmit driving force received from the engine via the transmission to the axle side and to be able to switch between a differential lock state and a differential lock release state;
an operating means for selecting whether to set the differential device to a differential lock state or a differential lock release state;
a controller capable of determining the gear position of the transmission and the vehicle speed;
A vehicle system comprising:
The transmission is a belt type continuously variable transmission as an automatic transmission,
The controller is configured to cause the belt-type continuously variable transmission to shift to the lowest gear range for forward movement or the lowest gear range for reverse movement when an operation is performed using the operating means to set the differential gear from a differential lock release state to a differential lock state. Determining whether or not a first condition, which is a gear change range, and a second condition, which is a vehicle speed being equal to or less than a predetermined speed, are satisfied, and on the condition that the first and second conditions are satisfied, The differential device is configured to execute an operation of switching the differential device to a differential lock state, and otherwise perform control not to switch the differential device to the differential lock state , and
During the setting period of the differential lock state, the shift range of the belt type continuously variable transmission is maintained at the lowest or reverse range, and the belt is adjusted so that the output torque from the belt type continuously variable transmission is maximized. A vehicle system characterized by being configured to perform control to maximize the reduction ratio of a continuously variable transmission .

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