JP2584744Y2 - Steering operation device for driving front wheels in four-wheel drive vehicle - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a turning configuration in which the power of the driving rear wheel on the turning side is cut off while being braked and the turning is performed, and the driving front wheel and the driving rear wheel on the turning side are the driving front wheels on the turning outer side. The present invention also relates to a steering operation device for a front drive wheel in a four-wheel drive vehicle, which can selectively perform a pivot turn in which the vehicle rotates in the opposite direction with respect to the drive rear wheel.

[0002]

2. Description of the Related Art In a conventional four-wheel drive vehicle, a front drive steering device for driving a vehicle drives left and right driving front wheels in parallel, turns off a driving rear wheel on a turning side and cuts off the driving rear wheel. The vehicle is turned by braking or the drive front wheel and the drive rear wheel on the turning side are rotated in opposite directions with respect to the drive front wheel and the drive rear wheel on the opposite side (outside of the turn) to make a pivot turn.

[0003]

In the prior art, the turning front drive wheel and the rear drive wheel on the turning side are rotated in the opposite directions with respect to the drive front wheel and the rear drive wheel on the outside of the turn to perform a pivot turn. In this case, since the left and right driving front wheels are parallel to each other, there is a problem that turning resistance applied to the driving front wheels is large and the radius of the pivot turn becomes large.

In the present invention, when the driving front wheel and the driving rear wheel on the turning side are rotated in the opposite directions with respect to the driving front wheel and the driving rear wheel on the outside of the turning, the left and right driving front wheels face inward each other in plan view. The turning operation is performed so that the turning resistance is reduced and the turning radius is reduced, and the left and right driving front wheels are turned in parallel so that the turning rear driving wheel can be braked and turned. In addition, the turning mode of the driving front wheel can be switched without erroneous operation in connection with the switching of the rotation direction switching mechanism of the driving front wheel.

[0005]

In order to achieve the above object, the present invention provides a pair of left and right driving rear wheels (2a) (2).
b) and driving front wheels (1a) (1b), and a pair of left and right driving front wheels (1a) (1b) are connected to a steering wheel (1).
In the four-wheel drive vehicle which is steered by turning in 5), a pair of left and right driving rear wheels (2a) is provided from the engine (3).
(2b), a pair of left and right side clutch mechanisms (8a) and (8b) and steering brake mechanisms (9a) and (9b), and a pair of left and right driving rear wheels (2a) and (2).
b) rear wheel rotation direction switching mechanisms (7a) and (7b) capable of individually switching the rotation direction, and branching from the rear wheel drive path to the left and right driving front wheels (1a) (1b). The left and right driving front wheels (1a) are included in the transmitted front wheel driving path.
While a front wheel rotation direction switching mechanism (10) capable of individually switching the rotation direction of (1b) is provided, an operating mechanism linked to the steering handle (15) is linked to the left and right knuckle arms (12a) (12b). Drag rod (1
4a) and (14b), the left and right driving front wheels (1a) (1
b) a first operating mechanism (B) that turns parallel and a tie rod (13) that connects the left and right knuckle arms (12a) and (12b) into two right and left parts, and an operation rod (20) that is pivotally connected. The left and right driving front wheels (1a) and (1b) are configured into two systems of a second operation mechanism (C) that turns inward in a plan view, and the first operation mechanism (B) and the second operation mechanism An operation selection mechanism (D) for selecting (C) is provided. When the operation selection mechanism (D) selects the first operation mechanism (B), the left and right driving front wheels (1a) (1
b) and the rear drive wheels (2a) and (2b) all rotate in the same direction, and when the second operating mechanism (C) is selected, the front drive wheel and the rear drive wheel on the turning side become the front drive wheel and the drive on the outside of the turn. It is designed to rotate in the opposite direction to the rear wheel.

[0006]

In the steering front steering device having the above structure, the first operating mechanism (B) is selected by the operation selecting mechanism (D), and the driving front wheel (1a) is operated by the first operating mechanism (B). When the turning of (1b) is performed, the rotation direction switching mechanisms (7a) and (7b) of the rear wheels and the rotation direction switching mechanism (10) of the front wheels are driven by the left and right driving front wheels (1a) and (1b) and the driving rear wheels. (2a) and (2b) are all rotated in the same direction. In this state, the left and right driving front wheels (1a) and (1b) are turned in parallel to the turning side (for example, right side) by the first operating mechanism (B), and the turning side driving rear wheel (2b). The side clutch mechanism (8b) is disengaged, and the steering brake mechanism (9b) on the same side is braked to turn (turn right) the vehicle.

When the second operating mechanism (C) is selected by the operation selecting mechanism (D) and the driving front wheels (1a) and (1b) are turned by the second operating mechanism (C), the rear operation is performed. The rotation direction switching mechanisms (7a) and (7b) for the wheels and the rotation direction switching mechanism (10) for the front wheels are used to drive the left and right driving front wheels (1).
a) (1b) and the driving rear wheel (2a) (2b) are switched to a state in which the driving rear wheel (2a) and the driving front wheel (1a) on the outer side of the turning are rotated in the opposite directions. In the case of the second operating mechanism (C), the left and right driving front wheels (1a)
(1b) are turned inward to each other in plan view, and the vehicle makes a pivot turn.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a tractor (A) which is a four-wheel drive vehicle will be described with reference to the drawings.
The tractor (A) includes a pair of left and right driving front wheels (1a) (1
b) and a pair of left and right driving rear wheels (2a) (2b). Then, after the power of the engine (3) can switch the rotation directions of the main clutch mechanism (4), the transmission mechanism (5), the differential mechanism (6), and the left and right driving rear wheels (2a) (2b) separately. Driven via a transmission path to the rear wheels, which is composed of a wheel rotation direction switching mechanism (7a) (7b), a pair of left and right side clutch mechanisms (8a) (8b) and steering brake mechanisms (9a) (9b). Transmitted to the rear wheels (2a) and (2a),
A transmission path to a front wheel provided with a front-wheel rotation direction switching mechanism (10) that branches from the transmission rear position of the transmission mechanism (5) and that can switch the rotation direction of the left and right driving front wheels (1a) and (1b) separately. It is configured to be transmitted to the driving front wheels (2a) and (2b) via the driving wheels.

The driving front wheels (1a) and (1b) are rotatably supported around the king pins (11a) and (11b) so that the steering angle can be changed.
Knuckle arm (12a) attached to (11b) (1
2b) is connected by a tie rod (13), and drag rods (14a) (14b) pivotally attached to the knuckle arms (12a) (12b) are pivotally connected to a sector gear (16) which rotates around a support shaft. The sector gear (16) is meshed with a turning gear (18) loosely fitted to a handle shaft (17) having a steering handle (15).

The rotation of the sector gear (16) pushes and pulls the drag rods (14a) and (14b) in directions opposite to each other, so that the drive front wheels (1a) and (1b) are parallel as shown in FIG. It is designed to be turned in a state.
In addition, these revolving gear (18), sector gear (16),
The drag rods (14a) (14b) and the knuckle arms (12a) (12b) are collectively referred to as a first operation mechanism (B).

The tie rod (13) is divided into two parts at an intermediate portion thereof.
(13b), both split tie rods (13a)
(13b) is connected by the connecting pin (19), one end of the operating rod (20) is connected to the connecting pin (19), and the other end of the operating rod (20) is connected to the handle shaft (1).
7) pivotally connected to a swing arm (21) loosely fitted in
As the swing arm (21) rotates, the operating rod (20) and the split rods (13a) (13b) are pulled, and the driving front wheels (1a) (1b) are mutually moved in plan view as shown in FIG. The turning arm (21) and the operating rod (20) are turned inward.
The knuckle arm (12) is generically referred to as a second operation mechanism (C).

A pin clutch body (22) [operation selection mechanism D] engaged with the handle shaft (17) is mounted between the swing gear (18) of the handle shaft (17) and the swing arm (21). When the pin (22a) or the pin (22b) is slid up and down, the pin clutch body (22) is turned into the pin hole (18a) of the turning gear (18) or the turning arm (2).
It is configured to engage with the pin hole (21a) of 1).

As shown in FIGS. 4 and 5, the pin clutch body (22) comprises a rear wheel rotation direction switching mechanism (7a) (7).
b) The operation lever (23) for operating the front wheel rotation direction switching mechanism (10) is slidably linked via a link mechanism (24), and the operation lever (23) is moved to the (X1) position. When operated, the first operating mechanism (B) becomes operable, and when the operating lever (23) is operated to the (X2) position, the second operating mechanism (C) becomes operable, and
When the operation lever (23) is operated to the (X1) position,
The differential mechanism (6) is locked by the control mechanism (24), and the rotation direction switching mechanisms (7a) and (7b) for the rear wheels and the rotation direction switching mechanism (10) for the front wheels are all operated to rotate in the same direction. When the operation lever (23) is operated to the (X2) position and is operated rightward in the lever guide hole (25) shown in FIG. 5, the rotation direction switching mechanism (1
0) and the turning direction switching mechanism (7b) of the turning side rear wheel are operated, and the turning front driving wheel (1b) and the driving rear wheel (2b) are operated.
b) is a driving front wheel (1a) and a driving rear wheel (2
It is configured to be reversed with respect to a). Also,
When the operation lever (23) is operated to the opposite side (X2) position and is operated leftward in the lever guide hole (25), the rotation direction switching mechanism (10) for the front wheels and the rear side opposite to the above. The rotation direction switching mechanism (7a) of the wheels is operated so that the front drive wheel (1a) and the rear drive wheel (2a) are reversed with respect to the opposite drive front wheel (1b) and the rear drive wheel (2b). Is configured.

Therefore, when the operating lever (23) is operated to the position (X1) to select the first operating mechanism (B), the driving front wheels (1a) (1b) and the driving rear wheels (2a) (2b) are all As shown in FIG. 1, the steering wheel (17) is rotated in the direction of the arrow (b), which is the right direction, and the steering pedal (26) is depressed. As shown in FIG. 2, the first operating mechanism (B) is operated, and the front drive wheels (1a) and (1b) are turned parallel to the right direction and at the same time the side of the right drive rear wheel (2b). Clutch The clutch mechanism (8b) is disconnected, the steering brake mechanism (9b) is operated, and the tractor (A) turns right.

Next, when the operation lever (23) is operated to the (X2) position and the second operation mechanism (C) is selected by operating rightward in the lever guide hole (25), the right driving front wheel is operated. (1b) and the driving rear wheel (2b)
As shown in FIG. 3, the drive front wheel (1a) on the opposite side (left side)
And the driving rear wheel (2a) is rotationally driven in the opposite direction (c). At this time, when the steering handle (17) is turned in the direction of the right arrow (b),
As shown in FIG. 3, the drive front wheels (1a) and (1b) are turned inward each other in a plan view, and the tractor (A)
Turns right. Note that the left turn of the tractor (A) is performed by an operation opposite to the above.

[0016]

[Effects of the Invention] The present invention is configured as described above, and has the following effects.

At the time of pivot turn, the drive front wheel (1
b) or (1a) and the driving rear wheel (2b) or (2a)
Is the drive front wheel (1a) or (1
b) and the drive rear wheels (2a) or (2b) rotate in opposite directions, and the left and right drive front wheels (1b) (1a).
Are turned inward to each other and are positioned in the direction along the turning center, so that turning resistance is reduced and a pivot turning with a small turning radius is performed.

Rear wheel rotation direction switching mechanism (7a) (7
b) The left and right driving front wheels (1a) (1) are operated by an operation lever (23) for operating a rotation direction switching mechanism (10) of the front wheels and the like.
Since the first operation mechanism (B) or the second operation mechanism (C) that turns b) is selected as an alternative, an erroneous operation does not occur.

[Brief description of the drawings]

FIG. 1 is a plan view of a main part of the device of the present invention.

FIG. 2 is an explanatory plan view showing an operation state of the device of the present invention.

FIG. 3 is an explanatory plan view showing an operation state of the device of the present invention.

FIG. 4 is an explanatory diagram of an operation device.

FIG. 5 is a plan view of a lever guide hole.

FIG. 6 is a side view of a tractor embodying the present invention.

[Explanation of symbols]

 1a Drive front wheel 2b Drive front wheel 2a Drive rear wheel 2b Drive rear wheel 3 Engine 7a Rear wheel rotation direction switching mechanism 7b Rear wheel rotation direction switching mechanism 8a Side clutch mechanism 8b Side clutch mechanism 9a Steering brake mechanism 9b Steering brake mechanism Reference Signs List 10 Front wheel rotation direction switching mechanism 12a Knuckle arm 12b Knuckle arm 13 Tie rod 14a Drag rod 14b Drag rod 15 Steering handle 20 Operation rod 23 Operation lever B First operation mechanism C Second operation mechanism D Operation selection mechanism

Claims (1)

(57) [Scope of request for utility model registration] 1. A pair of left and right driving rear wheels (2a) and (2b) and driving front wheels (1a) and (1b) are provided, and a pair of left and right driving front wheels (1a) and (1b) are turned by a steering handle (15). In a four-wheel drive vehicle to be steered, a pair of left and right driven rear wheels (2a) (2b) from an engine (3)
The left and right side clutch mechanisms (8a) and (8b) and the steering brake mechanism (9)
a) (9b) and a rear wheel rotation direction switching mechanism (7) that can separately switch the rotation direction of the left and right driving rear wheels (2a) (2b).
a) and (7b), and the left and right driving front wheels (1a) (1b) are branched from the rear wheel driving path to transmit power to the left and right driving front wheels (1a) and (1b). A front wheel rotation direction switching mechanism (10) capable of individually switching the rotation direction of the steering wheel (1) is provided.
The operating mechanism linked to 5) is the left and right knuckle arms (1
2a) Drag rod (14a) linked to (12b)
(14b) A first operating mechanism (B) for turning the left and right driving front wheels (1a) (1b) in parallel with a tie rod (1) for connecting the left and right knuckle arms (12a) (12b).
3) The operation rod (2
0), the left and right driving front wheels (1a) and (1b) are formed into two systems of a second operation mechanism (C) that turns inward in a plan view, and the first operation mechanism (B) and the second operation mechanism
An operation selection mechanism (D) for selectively operating the operation mechanism (C) is provided, and the operation selection mechanism (D) is used as a rear wheel rotation direction switching mechanism (7a) (7b) and a front wheel rotation direction switching mechanism. (10) is operatively connected to an operating lever (23),
When the operation selecting mechanism (D) selects the first operating mechanism (B), the left and right driving front wheels (1a) (1b) and the driving rear wheels (2a) (2b) all rotate in the same direction, and When the operating mechanism (C) is selected, the front drive wheel and the rear drive wheel on the turning side rotate in the opposite directions to the front drive wheel and the rear drive wheel on the outside of the turn. Steering operation device for driving front wheels in a vehicle.