JPH04201628A - Front wheel drive safety device when turning mobile vehicles - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a front wheel drive safety device for turning a moving vehicle.

This invention provides a mobile vehicle that mainly travels in fields.
When traveling at low speeds in narrow fields, the aircraft makes sharp turns, and when traveling at high speeds on roads or in large fields, the aircraft attempts to make slow turns.

[Prior Art and Problems to be Solved by the Invention] Conventionally, a mechanism for making a sharp turn in a narrow farm field at low speed has been known and is usually called a double-speed turn or a full turn.

Generally, when the turning angle of the steering wheel exceeds a certain level, the circumferential speed of the front wheels is changed to approximately double or more.

However, with conventional models like this, if you drive on the road with this mechanism, if you turn the steering wheel sharply at an intersection or curve, the circumferential speed of the front wheels will automatically increase, causing a large lateral movement of the front of the aircraft, resulting in the risk of rolling over. If you do so, there is a risk that the vehicle will fly off the road, so it is necessary to have a manual cut operation device for deactivation, a sensor that automatically measures the vehicle speed and cuts at high speed or at the gear lever position. It has become difficult and expensive.

[Means for Solving the Problems] The present invention attempts to solve the above-mentioned problems of the conventional device, and takes the following technical measures. That is, in a four-wheel drive vehicle that drives front wheels 1 and rear wheels 2, a clutch 3 for connecting and disconnecting the driving force is provided in the drive path between the front and rear wheels 1. A front wheel transmission mechanism 6 is provided for switching the circumferential speed of the front wheels 1 to a first gear ratio 4 having approximately the same circumferential speed and a second gear ratio 5 having approximately double the circumferential speed. A steering sensor 8 that detects that the amount of steering is more than a certain amount to the left or right, and left and right independent brakes 9 for the rear wheels 2.
．． A one-side brake sensor 11 is provided to detect operation on only one side of the lO, and when the vehicle is running straight, the front and rear axles 1 and 2 are driven in four-wheel drive at a first gear ratio of 4, and then the steering is performed as the vehicle moves straight to turn. If only the sensor 8 senses operation, the clutch 3 is disengaged and the vehicle runs in two-wheel drive using only the rear axle 2. If both the steering sensor 8 and the one-brake sensor 11 sense operation from straight-ahead to cornering, the clutch is disengaged. This is a front wheel drive safety device when a mobile vehicle turns, characterized in that the front wheel 1 is switched to a second gear ratio 5 after the front wheel 1 is turned off, thereby increasing the speed of the front wheel.

[Function] From straight forward running in four-wheel drive with the front wheels 1 and rear axle 2 at the first gear ratio 4 with approximately the same circumferential speed, the steering sensor 8 detects when the steering wheel 7 is steered to the left or right by more than a certain amount. Then, the clutch 3 disposed between the front and rear wheels 1.2 operates in a power-off state, and the vehicle turns with two-wheel drive using only the rear axle 2.

From straight forward driving in four-wheel drive with the front wheels 1 and rear axle 2 at the first gear ratio 4 at approximately the same circumferential speed, one rear wheel 2 is braked and the steering wheel 7 is steered to the left or right by a certain amount. When both the one-side brake sensor 11 and the steering sensor 8 sense this, the clutch 3 disposed between the front and rear wheels 1 and 2 is operated to cut off the power, and then the front wheel transmission mechanism 6 is operated to shift to the second gear ratio 5. , the turning is performed in four-wheel drive running with the circumferential speed of the front wheels 1 increased to approximately twice the circumferential speed of the rear wheels 2.

From straight forward driving in four-wheel drive with the front wheels 1 and rear wheels 2 at the first gear ratio 4 at approximately the same circumferential speed, the steering wheel 7 is steered to the left or right by a certain amount while simultaneously braking the left and right rear wheels 2. Then, since both brakes are used, one brake sensor 11 becomes non-sensing, and only the steering sensor 8 senses, and the clutch 3 disposed between the front and rear wheels 1 and 2 operates in a power-off state, and the rear axle 2 Only two-wheel drive is required for turning.

In the present invention, these judgments are automatically judged and controlled by the turning angle of the handlebar 7 and the independent or simultaneous operation of the independent brakes 9 and 10 of the rear shaft 2.

[Effects of the Invention] The present invention has the following technical effects due to the above configuration. That is, when a W-like person is turning the vehicle in a narrow field, he instinctively brakes only one side of the rear axle 2 strongly to turn, and in a field with a wide margin, he turns only by operating the handle 7, and on the road, he turns by only operating the handle 7. Utilizing the habit of turning while braking the left and right rear wheels 2 and 2 simultaneously, the front and rear wheels 1 and 2 are driven at the first gear ratio 4 at approximately the same circumferential speed when driving straight without any other special operation. When a running vehicle is to be turned by braking one side of the rear axle 2, the front wheels are shifted to the second gear ratio 5, which makes a four-wheel drive turn at approximately twice the speed of the rear axle 2, and only the steering wheel 7 is operated. When turning with the brakes or when turning while braking the rear axle 2 at the same time, the clutch 3 is disengaged and the rear axle 2 is driven only to slowly turn without roughening the ground surface. Furthermore, since the clutch 3 is in a neutral state in which the power is cut off during switching between the first gear ratio 4 and the second gear ratio 5, the feeling of shifting is improved smoothly.

[Examples] Examples of the present invention will be described in detail below with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the component parts described in this example are not intended to limit the scope of this invention to only those, unless there is a specific description. , is merely an illustrative example.

The rotation is an agricultural tractor 12 in which the present invention is incorporated into the drive path of the front wheels 1 of the four-wheel drive device.

As shown in the overall side view and driving diagram, the driving force of the agricultural tractor 12 is transmitted from the engine 13 at the front of the machine, through the main clutch 14, the main transmission 15, and the auxiliary transmission 16 to the rear differential 17. The rear wheels 2, 2 are driven, and the front wheels 1, 1 are also driven via an output gear 18 provided at the front of a rear differential device 17.

To explain the front wheel drive side in detail, the driving force of the output gear 18 reaches the front wheel transmission mechanism 6 via a passive gear 19 and a passive shaft 20.

The driving force that has passed through the front wheel transmission mechanism 6 is transmitted from a front drive shaft 21 to a front differential device 22 to drive the left and right front wheels 1, 1.

23 is the final reduction part of the front wheel 1.

In short, the front wheel transmission mechanism 6 transmits and switches the rotation of the passive shaft 20 to the front drive shaft 21 at a rotation ratio of approximately 1 or 2.

In rotation, two hydraulic multi-disc clutches 3a, 3b, a pair of same-speed side gears 4a, 4b, and another pair of double-speed side gears 5a,
5b, the front and rear wheels 1. 2
The two multi-disc clutches 3b are hydraulically compressed and the rotation of the passive shaft 20 is controlled by the double-speed side gears 5a, 5b.
The front wheels drive the front drive shaft 21 at a second gear ratio of 5 through a four-wheel drive state of approximately double speed, and two hydraulic multi-disc clutches 3a.
, 3b can be operated in three modes, including two-wheel drive after cutting off the supply of pressure oil to 3b.

A steering handle 7 is attached to the center of the aircraft body in the longitudinal direction, and is operated by a driver sitting on a seat 24.

Independent left and right brake pedals 25 are located below the handle 7.
．． 26 are disposed, and are interlocked and connected to the left and right rear wheels 2.2 by operating tools 27, such as rods and oil passages.

The brake pedals 25, 26 are mounted so as to be able to swing freely around a shaft 28, and the one-side brake sensor 11 mounted on the beta boss 29 reads the swing angle with respect to the shaft 28, which is integral with the machine frame. 26
Detects the operation of the

When rotating, the sphere 3 is inserted into the notch groove 30 provided in a part of the shaft 28.
1 is inserted, and the extendable tool 32 of the one-sided brake sensor 11 is brought into contact with this sphere 31.

FIG. 3(a) shows the telescopic tool 32 of the one-side brake sensor 11.
Indicates a non-operating state with extended beta.

FIG. 3(B) shows a state in which the pedal is not being sensed by the pedal, in which the pedal is being pushed a little but the telescoping tool 32 of the one-side brake sensor 11 is not yet fully retracted.

FIG. 3(C) shows the sensor sensing state when the pedal is actuated and the extendable member 32 of the one-side brake sensor 11 is fully retracted as the petal is pushed sufficiently.

33 in Fig. 1 is the pitman 7-m, and its position is shown when driving straight.By steering the wheel 7 to the left or right, it moves in the direction of arrow A or in the opposite direction of arrow A. either of the steering sensors 8, 8 is activated.

In the embodiment, the steering sensor 8 is disposed on the pitman arm 33, but it may be disposed on any part that moves during steering, such as a tie rod, a truss rod, or a handle shaft.

The electric circuit of a part of the sensor will be explained mainly with reference to FIG.

34 is a three-position changeover switch, and includes an "automatic safe shift" circuit 35 that automatically changes gears from the same-speed four-wheel drive to rear two-wheel drive or double-speed front four-wheel drive as described in this invention;
The circuit 36 dedicated to rear two-wheel drive is manually switched to the circuit 37 dedicated to four-axle drive, which has substantially the same speed for the front and rear wheels.

That is, when the "automatic safe shift" circuit 35 is in the contact position, the present invention is activated.

At the contact position of the rear two-wheel drive dedicated circuit 36, only the rear two-wheel drive is performed, regardless of the position of each sensor.

At the contact point position of the circuit 37 dedicated to four-wheel drive, where the front and rear wheels have approximately the same speed, no matter where each sensor is located, only four-wheel drive is performed where the front and rear wheels have approximately the same speed.

11 is a one-side brake sensor, and left and right brakes 9,
Two of them are provided for 10, and a specific signal is issued only when one of them is activated alone, and when both of them are activated, it is the same as when they are not activated.

8 is a steering sensor which outputs a signal when the steering angle of the handle 7 exceeds a certain level.

Each of these sensors is connected to the controller 38, and finally either one of the front wheel double speed solenoid valve 39 and the front wheel same speed solenoid valve 40 is activated or all of them are deactivated.

The front wheel double speed solenoid valve 39 and the front wheel same speed solenoid valve 40 change the flow direction of high pressure oil in the oil passage switching valve 41, and transfer the pressure oil from the pump 42 to the hydraulic multi-disc clutch. 3a or 3b, or discharged to a tank 44 through a discharge path 43.

[Brief explanation of the drawing]

The figure shows one embodiment of the invention. Figure 1 is an overall explanatory diagram, Figure 2 is a side view showing the brake sensor, Figures 3 (a), (b), and (c) are illustrations of its operation, Figure 4 is an electrical circuit diagram, and Figure 5 The figure is an overall side view. In the figure, 1 is a front wheel, 2 is a rear wheel, 3 is a clutch, 4 is a first gear ratio, 5 is a second gear ratio, 6 is a front wheel transmission mechanism, 7 is a handle 58 is a steering sensor, 9 and 10 are left and right 11 is a single brake sensor.

Claims (1)

[Claims] (1) In a four-wheel drive vehicle that drives the front wheels 1 and rear wheels 2, a clutch 3 is provided in the drive path between the front and rear wheels 1 and 2 to connect and disconnect the driving force, and the clutch 3 connects and disconnects the driving force to the rear wheels. A front wheel transmission mechanism 6 is provided which changes the circumferential speed of the front wheels 1 to a first gear ratio 4 which has approximately the same circumferential speed and a second gear ratio 5 which has a circumferential speed that is approximately double. a steering sensor 8 that detects that the amount of steering is greater than a certain amount in the left or right direction; and left and right independent brakes 9 for the rear wheels 2;
Single brake sensor 1 that detects operation on only one side of 10
1 is provided, and when the vehicle is running straight, the front and rear wheels 1 and 2 are driven in four-wheel drive at the first gear ratio 4. Next, when only the steering sensor 8 senses operation during a turning operation from straight running, the clutch 3 is set. If the steering sensor 8 and the one-side brake sensor 11 detect activation when driving straight and turning, the clutch 3 will be turned off.
A front wheel drive safety device for a moving vehicle when turning, characterized in that the front wheel 1 is switched to a second gear ratio 5 after the front wheel is turned off to perform four-wheel drive driving with front wheel speed increase.