JPH059292B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in a switching device for changing driving conditions of a vehicle.

[Prior art] While driving a vehicle, the driver judges the driving situation and operates the steering wheel with one hand while operating a control lever etc. with the other hand. It is being operated.
For example, manual switching between two-wheel drive and four-wheel drive in a four-wheel drive vehicle is performed by operating with one hand an operating lever connected to a switching mechanism provided in the transfer device of the vehicle.

However, depending on the driving situation, it is often necessary to operate the steering wheel with both hands. For example, when driving on a rough road or the like at or near the limit, it is essential to operate the steering wheel quickly, and there may be little time to take one hand off the wheel. If an attempt was made to take one hand off the wheel and perform the switching operation, there was a risk that the steering wheel would come off and the vehicle would become unstable. For this reason, it may not be possible to switch the transfer device or the like while driving on a rough road, and there is a risk that the performance of the vehicle may not be fully demonstrated.

[Object of the Invention] Therefore, it is an object of the present invention to provide a switching device that makes it possible to switch devices that require a switching operation without having to take one's hands off the steering wheel.

[Structure of the Invention] In order to achieve the above object, the present invention includes a detection means for detecting the angular velocity or angular acceleration of the steering shaft, and a steering wheel whose detection signal is mixed into the steering operation movement from the detection signal from the detection means. determining means for identifying a switching command operation movement within the play range of the switching command and extracting it as a switching command signal; and switching a device requiring a switching operation based on the switching command signal extracted by the determining means. The structure consists of an actuator.

[Embodiment] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings of FIGS. 1 to 3.

A transfer 5 is provided downstream of an engine 1 and a transmission 3 of a four-wheel drive vehicle, from which driving force is distributed and transmitted to a front drive shaft 7 and a rear drive shaft 9. The driving force of each of these drive shafts 7 and 9 is further applied to a front wheel differential 11 and a rear wheel differential 1, respectively.
3, and each left and right wheel 15a, b,
This leads to c and d. Steering device 17 on the front wheel side
is tie rod 19, steering shaft 21,
It is comprised of a steering wheel 23 and the like. Inside the transfer shaft 5, the rear wheel drive shaft 9 connects a solenoid coil 2 with a connection mechanism (not shown).
5 or a manual operation lever (not shown) to disconnect or disconnect the connection.

A speed sensor 27 is provided close to an internal rotating shaft (not shown) of the transmission 3, and detects a pulse signal proportional to the rotational speed of the rotating shaft. On the other hand, the steering shaft 21 is provided with a detection means 29 that detects the angular velocity or angular acceleration of rotation, and detects the angular velocity or angular acceleration of the rotation of the steering shaft 21 . Detection means 29 consists of a pulse encoder that outputs pulses according to the amount of rotation of the steering shaft 21, and an arithmetic device that inputs the pulses and uses them to calculate angular velocity or angular acceleration. Note that this arithmetic device may be incorporated into the next determining means 31. The signals from the speed sensor 27 and the detection means 29 are input to the judgment means 31, where the switching command operation movement mixed into the steering operation movement, for example, a rapid number of minute rocking angles to the left and right, is detected. The motion is identified and extracted as a switching command signal. Then, this extraction signal is amplified and output to operate the solenoid coil 25, and in this case, the coupling mechanism in the transfer 5, which is a device that requires a switching operation, is operated, and the rear wheel drive shaft is An actuator 33 is provided that connects and connects 9 to the transfer. In this embodiment, the determining means 31 uses a microcomputer, and the actuator 33 includes an amplifier 37, the solenoid coil 25, a relay, and the like. A block diagram of the above electric circuit is shown in FIG. 2, and a flowchart of the microcomputer is shown in FIG.

The operation of the apparatus of the present invention constructed in this manner will be described below.

Although the switching operation is basically possible by detecting either angular velocity or angular acceleration, an example in which the switching operation is performed by detecting angular acceleration will be described here.

During normal steering wheel operation, for example, rocking and rotating the steering wheel 23 back and forth 1 to 2 times to the left and right at an angle of about 2 to ^{30 degrees} within the range of play is a command signal for switching from two-wheel drive to four-wheel drive. For example, at a speed of 30 to 60 Km/Hr, the characteristics such as the period, amplitude, and number of oscillations are Bcm/
The acceleration signal of sec ² is inputted in advance to the switching command signal reference value setting circuit of the microcomputer 35 and stored as twice or more within 2 to 4 seconds. The above-mentioned movement of the steering wheel 23 is close to the range of play of this wheel, and has no effect on normal steering at all. Additionally, this car uses a mechanism for switching between four-wheel drive and two-wheel drive that can be operated while driving without any problems.

If you are driving this car at high speed on a rough road and come to a slope and want to switch from two-wheel drive to four-wheel drive, keep both hands on the steering wheel 23 and swing the wheel 23 left and right as agreed above. . This rocking motion is Bcm/
sec ² with almost equal acceleration motion of Acm/sec ² , 3
Twice per second. The detection means 29 captures this,
It is processed by the steering angular velocity detection circuit in the detection means 31 and outputted to the comparator twice every 3 seconds as angular acceleration signals A ₁ and A ₂ . (Step 1 in Figure 3) On the other hand, the speed sensor 27 captures the pulse signal from the rotating shaft in the transmission 3, enters the speed detection circuit in Step 2 in Figure 3, and processes it as a speed signal in Step 3. The switching command signal is input to the reference value setting circuit,
Here, an angular acceleration signal reference value B corresponding to the speed signal, that is, a switching command signal corresponding to the vehicle speed is selected and taken out and inputted to the next comparator. In step 4, the angular acceleration signal _A1 and the signal reference value B are first compared once. If the difference between the two is large, the answer is NO and the process returns to step 1. If the two are almost equal, a second comparison is made between _A2 and B in step 5.
If NO, the process returns to step 1, and if they are almost equal, it is determined that it is a switching designation signal, and the process proceeds to step 6, where it is taken out as a switching designation signal and output to the actuator 33 in step 7.

The signal inputted to the actuator 33 is amplified by the amplifier 37, and the solenoid coil 25 is energized via a relay or the like, and the transfer 5 operates the unillustrated coupling mechanism of the rear wheel drive shaft 9 to the coupling side, thereby connecting the four wheels. Switching to drive is complete. When switching from four-wheel drive to two-wheel drive, the same sequence of operations as above is performed, but the operation of transmitting a switching command signal at the steering wheel 23 is exactly the same as above, and this same signal is sent after a predetermined period of time has elapsed. Whether the command signal for reverse switching is a command signal for reverse switching, or a signal different from the above-mentioned signal, for example, a signal in which the number of oscillations is increased by one, is a command signal for reverse switching is arbitrarily selected and determined in advance. You can remember it like this. In addition, since the vehicle is in a running state where it is possible to release one hand, manual operation using a switching operation lever or the like is possible.

The invention is not limited to the embodiments described above. For example, several kinds of command signal transmission operations such as those described above for the steering wheel 23 can be set and stored, and in addition to switching between two-wheel drive and four-wheel drive, artificial intermittent operation of the deflock device and artificial operation of the suspension mechanism can be performed. It is also possible to use this switching device to perform various switching operations. Furthermore, the device of the present invention can be applied not only to vehicles but also to, for example, motor boats with steering wheels.

[Effects of the Invention] As explained above, the switching device of the present invention allows manual switching of the switching device depending on the driving conditions etc. easily and reliably while keeping both hands on the steering wheel, resulting in extremely safe driving. This makes it possible to fully demonstrate the driving performance of this vehicle. Furthermore, it is possible to operate a plurality of switching devices, etc., if necessary, and the range of application is wide. In addition, especially when angular acceleration is detected and limited, very slight changes can be detected within the range of play of the steering wheel, and control can be performed with good response.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a block diagram of the electric circuit of the device shown in FIG. 1, and FIG.
The figure is a flowchart of the microcomputer used in the apparatus shown in FIG. Explanation of main drawing symbols, 21... Steering shaft, 29... Detection means, 31... Judgment means, 33... Actuator.

Claims (1)

[Claims] 1. A detection means for detecting the angular velocity or angular acceleration of the steering shaft, and a switching command signal by identifying the switching command movement within the range of play of the steering wheel mixed into the steering operation movement from the detection signal by the detection means. 1. A switching device comprising: a determining means for extracting a switching command; and an actuator for switching a device requiring a switching operation based on a switching command signal extracted by the determining means.