JPH10114277A - Drive unit for sharp angle steering and front and rear wheels steering all wheels drive type vehicle using the drive unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the maximum change angles of front and rear wheels by providing a first tie-rod connected to one end of a link attached to a differential case of a first drive axle in such a manner that it can turn freely in the horizontal direction and an outer drive steering mechanism and a second tie-rod connected W to the other end of the link and the other outer drive steering mechanism. SOLUTION: The direction of front wheels is changed at two steps by an inner drive steering mechanism and an outer drive steering mechanism 7. First, a lock condition of hydraulic cylinders 13A, 13A is released. Then, the inner drive steering mechanism is turned in the horizontal direction by the hydraulic cylinders 13A, 13A by turning a steering wheel. A front wheel side case of a second front wheel drive axle 6 is turned and the front wheels turn by using this inner drive steering mechanism as a shaft. The inner drive steering mechanism turns by the maximum angle, stops, and enters a fixed condition. Then, a steering arm on front wheel side 12 on one side is turned. The turn of the steering arm on front wheel side 12 on one side is transmitted to the outer drive steering mechanism 7, and the front wheels turn furthermore.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive unit for steered at an acute angle and a front-rear-wheel steering all-wheel drive vehicle capable of performing steering drive on a front wheel side and a rear wheel side using the drive unit.

[0002]

2. Description of the Related Art A work vehicle such as a crane truck is required to have a small turning property in a narrow construction site. For example, a front-rear-wheel steering all-wheel drive vehicle capable of steering driving on a front wheel side and steering driving on a rear wheel side. Has been adopted. As a front-rear-wheel steering all-wheel drive vehicle, for example, a vehicle shown in FIG. 10 is known.

In FIG. 1, a front and rear wheel steering all-wheel drive vehicle 1 is shown.
Reference numeral 01 denotes a front wheel drive axle 102 that houses front wheel drive shafts 102A, 102A that rotate by a driving force transmitted from an engine (not shown) in a front wheel case 102B.
And a pair of drive steering mechanisms 103, 103, one side of which is connected to both sides of the front wheel drive axle 102, and the front wheel side steering provided on one drive steering mechanism 103 and rotated by a drag link (not shown). Arm 104
, One drive steering mechanism 103 and the other drive steering mechanism 1
03, a front wheel side tie rod 105, and front wheels 110,
110 and rear wheel drive shafts 106A, 106A that rotate by the driving force transmitted from the engine.
A rear wheel drive axle 106 housed inside the vehicle, a pair of drive steering mechanisms 107, 107 each having one side connected to both sides of the rear wheel drive axle 106, and one drive steering mechanism 107 are provided. Rear wheel steering arm 108
, One drive steering mechanism 107 and the other drive steering mechanism 1
07, a rear wheel tie rod 109, and rear wheels 111,
111 and a linkage (not shown) connected to the front wheel side steering arm 104 and the rear wheel side steering arm 108.

By turning a handle (not shown) clockwise or counterclockwise, for example, as shown in FIG. 11, the directions of the front wheels 110, 110 and the directions of the rear wheels 111, 111 can be changed.

[0005]

However, in the conventional front-rear-wheel steering all-wheel drive vehicle 101, the front wheels 110,
The maximum change angle of the rear wheel 110 and the rear wheels 111 is limited by the drive steering mechanism 103 on the front wheel side, the drive steering mechanism 107 on the rear wheel side, and the like. Therefore, the front-rear-wheel-steering all-wheel drive vehicle 101 cannot perform a sharp turning at an acute angle, and the turning property at a narrow construction site is insufficient. Is required.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to make the maximum change angle of the front wheel and the rear wheel approximately double, to enable a sharp turning and a right angle running, and to narrow the angle. An object of the present invention is to provide a front-rear-wheel steering all-wheel drive vehicle capable of ensuring small turning performance at a construction site.

[0007]

According to the first aspect of the present invention,
A first drive axle in which a first drive shaft rotated by a drive force transmitted from an engine is housed in a differential case, and a pair of inner drive steers each having one side connected to both sides of the first drive axle A pair of second drive axles, one of which is connected to the other side of each of the inner drive steering mechanisms and the second drive shaft is housed in a side case;
One side is connected to the other side of each second drive axle, and a pair of outer drive steering mechanisms for transmitting drive and steering to the tire, a steering arm provided on one outer drive steering mechanism, Operating means for rotating the second drive axle in the horizontal direction, a link rotatably mounted on the differential case of the first drive axle so as to be rotatable in the horizontal direction, one end of the link and one outer drive steering mechanism The first connected to
It is characterized by having a tie rod and a second tie rod connected to the other end of the link and the other outer drive steering mechanism.

According to a second aspect of the present invention, there is provided a front-wheel drive unit having one or more steep-angle steering drive units, and a rear-wheel drive unit having one or more steep-angle steering drive units. A front-wheel-side steep-angle steering drive unit includes a first front-wheel drive axle including a first front-wheel drive shaft that is rotated by a drive force transmitted from an engine and housed in a front-wheel differential case; A pair of inner drive steering mechanisms each having one side connected to both sides of the drive axle, and one side connected to the other side of each inner drive steering mechanism to accommodate the second front wheel drive shaft in the front wheel side case. A pair of second front wheel drive axles, a pair of outside drive steering mechanisms having one side connected to the other side of each second front wheel drive axle and transmitting drive and steering to the front wheels, and one outside Provided in the drive steering mechanism A wheel steering arm, the second
Front-wheel-side operating means for rotating the front-wheel drive axle in the horizontal direction, a front-wheel link rotatably mounted on the front-wheel differential case of the first front-wheel drive axle, and one end and one outer side of the front-wheel link The first connected to the drive steering mechanism
A front-wheel-side tie rod, a second front-wheel-side tie rod connected to the other end of the front-wheel-side link and the other outside drive-steering mechanism, and a rear-wheel-side steep-angle steering drive unit is transmitted from the engine. A first rear wheel drive axle that houses a first rear wheel drive shaft that is rotated by a driving force in a rear wheel differential case, and a pair of first rear wheel drive axles, one side of which is connected to both sides of the first rear wheel drive axle, respectively. A pair of second rear wheel drive axles, one of which is connected to the other side of the inner drive steering mechanism and the other side of each inner drive steering mechanism, and which accommodates a second rear wheel drive shaft in a rear wheel side case; And one side is connected to the other side of each second rear wheel drive axle, and is provided in a pair of outer drive steering mechanisms for transmitting drive and steering to the rear wheels, and one outer drive steer mechanism. Water the rear wheel side steering arm and each second rear wheel drive axle Rear-wheel operating means for rotating in the respective directions, a rear-wheel link rotatably mounted on a rear-wheel differential case of a first rear-wheel drive axle, one end of the rear-wheel link, and one outer drive A first rear wheel tie rod connected to the steering mechanism; and a second rear wheel tie rod connected to the other end of the rear wheel link and the other outer drive steering mechanism. I do.

(Function) In the first aspect of the present invention,
The case where the direction of the tire is one step (A) and the case where the direction of the tire is changed to two steps (B) are as follows.
In the case of (a), the inner drive steering mechanism and the side case of the second drive axle are in a fixed state, and only the outer drive steering mechanism is operated.

In this case, the direction of the tire falls within the range of the rotation limit angle when only the outer drive steering mechanism is used. In the case of (b), the direction of the tire can be changed in two stages by the inner drive steering mechanism and the outer drive steering mechanism. That is, first, the inner drive turning mechanism is operated by the operating means, and the inner drive turning mechanism rotates the side case of the second drive axle about the inner drive turning mechanism, thereby turning the tire. At this time, the outer drive steering mechanism is in a fixed state.

After the tire has turned a predetermined angle (the limit angle when only the inside drive steering mechanism is used), the inside drive steering mechanism operates at the maximum angle, and the operation is stopped. Subsequently, the inner drive steering mechanism is brought into a fixed state, and one steering arm is rotated. The rotation of one steering arm is transmitted to the outer drive steering mechanism, and the tire rotates.

The rotation of one steering arm is
One outer drive steering mechanism → first tie rod → link → second tie rod → the other outer drive steering mechanism is transmitted, and one outer drive steering mechanism and the other outer drive steering mechanism are operated simultaneously. . Thereby, the directions of the right and left tires become the same. In this way, the directions of the left and right tires can be changed in two stages.

According to the second aspect of the present invention, the following conditions are obtained when the front-rear-wheel steering all-wheel drive vehicle is traveling normally (A) and during special traveling (B) other than during normal traveling. (A) First, the normal traveling will be described. Normal traveling refers to a case where the front-rear-wheel steering all-wheel drive vehicle travels within the rotation limit angle of the front wheels when only one drive steering mechanism is used. The operation at the front wheel and the operation at the rear wheel are the same, and the operation at the front wheel will be described as an example.

The front drive wheel steering mechanism and the front wheel side case of the second front wheel drive axle are fixed. Only the outer drive steering mechanism is operated. In this case, the direction of the front wheels falls within the range of the rotation limit angle when only the outer drive steering mechanism is used. Only the outer drive steering mechanism is operated, and the directions of the left and right front wheels are simultaneously changed.

In this case, the direction of the front wheels falls within the range of the rotation limit angle when only the outer drive steering mechanism is used. Next, (b) special driving will be described. The operation at the front wheel and the operation at the rear wheel are the same, and the operation at the front wheel will be described as an example. Here, during special traveling (b), for example, there are the following cases.

(1) When the front and rear wheels are directed sideways, and the front and rear wheels are directed in the same direction, and the front-rear-wheel steering all-wheel-drive vehicle travels sideways. (2) Both the front wheels and rear wheels When the front-rear-wheel steering all-wheel drive vehicle is turned around its center, (3) at least one of the front wheels or the rear wheels is directed sideways,
When turning a front-rear-wheel steering all-wheel drive vehicle around the front side or rear side During special driving (b), the front wheel direction can be changed in two stages by the inner drive steering mechanism and the outer drive steering mechanism. .

That is, first, the inside drive steering mechanism is turned horizontally by the front wheel side operation means. The front wheel side case of the second front wheel drive axle is rotated about the inside drive steering mechanism by the inside drive steering mechanism, and the front wheels are turned. At this time, the outer drive steering device is in a fixed state. The inner drive steering mechanism is rotated by the maximum angle and stopped, and becomes a fixed state, and the rotation angle of the second front wheel drive axle reaches the limit angle. The front wheels are turned by a predetermined angle (the limit angle when only the inside drive steering mechanism is used).

Subsequently, one of the front-wheel-side steering arms is rotated. The rotation of one front wheel side steering arm is transmitted to one side drive steering mechanism, and the front wheels further rotate. It should be noted that the rotation of one front wheel side steering arm is 1
The outer drive steering mechanism → the first front wheel side tie rod → the front wheel side link → the second front wheel side tie rod → the other outer drive steering mechanism, one outer drive steering mechanism and the other outer drive steering mechanism. Are activated simultaneously. Thereby, the directions of the left and right front wheels become the same.

In this way, the directions of the left and right front wheels can be changed in two stages. The maximum change angle of the front wheels is the sum of the change angle θ1 of the front wheels due to the rotation of the second front wheel drive axle and the change angle θ2 of the front wheels with respect to the second front wheel drive axle.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 9, a drive unit for steep angle steering according to an embodiment of the present invention according to claim 1, and
A front-rear-wheel steering all-wheel drive vehicle according to the second embodiment of the present invention, which uses the drive unit for steep angle steering according to the first embodiment of the present invention, will be described.
When the front-wheel side and the rear-wheel side of the front-rear-wheel steering all-wheel drive type vehicle according to the present embodiment are configured as one axis and the rear wheel side is configured as one axis (that is, the front-wheel-side drive device is configured as one sharp angle (A case in which the rear wheel side drive device is formed by one steep angle steering drive unit).

In FIG. 6, reference numeral 1 denotes a front-rear-wheel steering all-wheel drive vehicle according to the present embodiment, and the front-rear-wheel steering all-wheel drive vehicle 1 comprises a front wheel steering unit 2A having one sharp angle steering drive unit. It is composed of a side drive device 2 and a rear wheel drive device 3 including one drive unit 3A for steered at a sharp angle, and is applied to, for example, a crane truck. The front-wheel-side drive unit for steep-angle steering 2A is shown in FIGS. 1 to 3, and the drive unit for steep-angle steering on the rear wheel side 3A is shown in FIGS. 4 and 5.

In FIGS. 1 to 3, a front-wheel-side steep-angle steering drive unit 2A includes a first front-wheel drive shaft 4A that is rotated by a driving force transmitted from an engine (not shown).
And a front wheel differential case 4 accommodating the first front wheel drive shaft 4A.
B, a pair of inner drive steering mechanisms 5, 5 each having one side connected to both sides of the first front wheel drive axle 4, Side is connected to one side, and the second front wheel drive shaft 6
A, 6A and a pair of second front wheel drive axles 6, 6 each including a front wheel side case 6B accommodating the second front wheel drive shaft 6A, 6A, and the other side of each second front wheel drive axle 6, 6 And a pair of outer drive steering mechanisms 7, 7 each having one side connected thereto, and bearings 8A,
8B and front hub 9 supported by bearings 8A and 8B
A drum unit 10 mounted on the front hub 9 and having a built-in brake device; a front wheel disk 11 mounted on the drum unit 10; and a front wheel steering arm 1 provided on one of the outer drive steering mechanisms 7.
2 and a front wheel differential case 4B of the first front wheel drive axle 4
From the front wheel side case 6 of each second front wheel drive axle 6
B, and the front wheel-side operating means 1 which is mounted on each of the front wheels B and rotates each of the second front wheel drive axles 6 in the horizontal direction.
3, 13; a front wheel link 14 pivotally mounted on a front wheel differential case 4B of the first front wheel drive axle 4 so as to be rotatable in the horizontal direction; and one end 14A of the front wheel link 14 and one outer drive steering mechanism. The first front wheel side tie rod 15 and the other end 1 of the front wheel side link 14 are respectively pin-connected to the arm 39 of the front wheel 7.
4B and the second front wheel side tie rod 16 pin-connected to the arm 39 of the other outer drive steering mechanism 7, respectively.

Then, on the front wheel side disc wheel 11,
A front wheel 11A made of a tire is mounted. FIG.
The inner drive steering mechanism 5 includes a spherical joint 18, an upper king pin 20 held above the spherical joint 18 via an upper bearing 19, and a lower bearing 21 below the spherical joint 18. And a held lower king pin 22. The upper kingpin 20 and the lower kingpin 22 define an axis 23 for rotating the spherical joint 18.

A female receiving portion 24 is provided on one side of the spherical joint 18, and an end 4C of the first front wheel drive shaft 4A is spline-connected to the female receiving portion 24. A female receiving portion 25 is provided on the other side of the spherical joint 18, and one end 6C of the second front wheel drive shaft 6A is spline-connected to the female receiving portion 25. The outer drive steering mechanism 7 includes a spherical joint 26, an upper king pin 28 held above the spherical joint 26 via an upper bearing 27, and a lower bearing 29 below the spherical joint 26. And a held lower king pin 30. An axis 31 when the spherical joint 26 is rotated by the upper king pin 28 and the lower king pin 30 is formed.

The female joint 32 is provided on one side of the spherical joint 26, and the other end 6D of the second front wheel drive shaft 6A is spline-connected to the female joint 32. On the other side of the spherical joint 26, a female receiving portion 33 is provided.
One end 34A of the front wheel drive shaft 34 is spline-coupled. An axle tube 35 is connected to the other side of the outer drive steering mechanism 7, and a third front wheel drive shaft 34 passes through the axle tube 35, and is provided on the outer peripheral surface of the axle tube 35 via bearings 8A and 8B. A front hub 9 is supported. The other end 34 </ b> B of the third front wheel drive shaft 34 is connected to the ring 9 </ b> A of the front hub 9 via a plurality of bolts 36.

In FIG. 2, the front wheel side operation means 13
Has hydraulic cylinders 13A, 13A. One end 13C of a cylinder body 13B of the hydraulic cylinder 13A is attached to a front wheel differential case 4B of the first front wheel drive axle 4 via a bracket 37, and the rod 1 of the hydraulic cylinder 13A
The front end of 3D is attached to the front wheel side case 6B of the second front wheel drive axle 6 via a bracket 38.

In FIG. 3, the base end of the front wheel-side steering arm 12 is provided integrally with the upper king pin 28 of the outer drive steering mechanism 7.
Is linked to the front wheel side drag link 12A.

An arm 39 is provided integrally with the front wheel side steering arm 12 as a part of the outer drive steering mechanism 7,
One end 15A of the first front wheel side tie rod 15 is pin-connected to the arm 39. Stoppers 6E, 6E are formed on the front wheel side case 6B so that the bolt 6A provided on the outer drive steering mechanism 7 hits the stopper 6E so that the rotation of the outer drive steering mechanism 7 is stopped. Has become.

Referring to FIGS. 4 and 5, a description will be given of the drive unit 3A for steered at an acute angle on the rear wheel side. The rear-wheel drive unit for steep-angle steering 3A has the same structure as the drive unit for front-wheel steep-angle steering 2A, and only the components will be described, and the description of the detailed portions will be omitted. In FIGS. 4 and 5, the drive unit 3A for steered at a sharp angle on the rear wheel side is shown.
Is a first rear wheel drive shaft 40A that rotates by a driving force transmitted from an engine (not shown), and a first rear wheel differential case 40B that houses the first rear wheel drive shaft 40A.
Rear wheel drive axle 40 and first rear wheel drive axle 4
A pair of inner drive steering mechanisms 41, 41 each having one side connected to both sides of 0, and one side connected to the other side of each inner drive steering mechanism 41, respectively, and second rear wheel drive shafts 42A, 42.
2A, a pair of second rear wheel drive axles 42, 42 each including a second rear wheel drive shaft 42A, 42A, and a rear wheel side case 42B accommodating the second rear wheel drive shafts 42A, 42A.
A pair of outer drive steering mechanisms 43, 43 each having one side connected to the other side of the outer drive steering mechanisms 2, 42, bearings 44A, 44B mounted on the outer drive steering mechanism 43, and a rear hub supported by the bearings 44A, 44B. 45, a drum unit 46 mounted on the rear hub 45 and having a built-in brake device, a rear-wheel disc wheel 47 mounted on the drum unit 46, and a rear-wheel steering arm provided on one of the outer drive steering mechanisms 43 48, and from the rear wheel differential case 40B of each first rear wheel drive axle 40 to the rear wheel side case 42B of each second rear wheel drive axle 42, the second rear wheel drive axle 42 is Rear wheel side operation means 49, 49 for rotating the
A rear wheel link 50 rotatably mounted in a horizontal direction on a rear wheel differential case 40B of the rear wheel drive axle 40, one end 50A of the rear wheel link 50 and one of the outer drive steering mechanisms 4.
The first rear wheel tie rod 51 is pin-connected to the third arm 43A, and the second rear wheel is pin-connected to the other end 50B of the rear wheel link 50 and the arm 43A of the other outer drive steering mechanism 43, respectively. And a side tie rod 52.

Then, the rear wheel side disc wheel 47
A rear wheel 47A made of a tire is mounted. The rear wheel side operation means 49 includes a pair of hydraulic cylinders 49A, 49A.
have. The distal end of the rear wheel steering arm 48 is linked to a rear wheel drag link 48A. The rear-wheel drag link 48A and the front-wheel drag link 12A are provided with a linkage mechanism (for example, Japanese Unexamined Patent Publication No.
291143), and by turning the steering wheel clockwise or counterclockwise, the front wheel side drag link 12
A, the rear wheel drag link 48A operates synchronously.

Further, a power steering device (not shown) is mounted on the handle 53 (shown in FIG. 6), and the hydraulic cylinder 13A and the hydraulic cylinder 49A are locked by the lock device during normal running in this power steering device. At the same time, during a special running (described later), a lock circuit to be unlocked and both or one of the hydraulic cylinders 13A, 13A and the hydraulic cylinders 49A, 49A are controlled, and then the front wheel side drag link 12A, the rear wheel side A sequential circuit in which both or one of the drag links 48A is activated is incorporated.

Next, the operation of the present embodiment will be described. The front-rear-wheel steering all-wheel drive vehicle 1 is used as follows depending on (a) normal driving and (b) special driving other than normal driving. First, (a) the case of normal traveling will be described. The operation at the front wheels 11A, 11A is the same as the operation at the rear wheels 47A, 47A.
The operation of the front wheels 11A, 11A will be described as an example.

"Normal traveling" refers to a case where the front-rear-wheel steering all-wheel drive vehicle 1 travels within the rotation limit angle of the front wheels 11A, 11A when only one drive steering mechanism is used. Hydraulic cylinder 13A, 1 by lock device
3A is controlled to a locked state, and the inner drive steering mechanism 5, the front wheel side case 6B of the second front wheel drive axle 6, is in a fixed state. By turning the handle 53 right or left, the front wheel side steering arm 12 is rotated by the front wheel side drag link 12A, and the outer drive steering mechanism 7 is turned.
Only activated. The front wheels 11A, 11A rotate around the outer drive steering mechanisms 7, 7, and the directions of the front wheels 11A, 11A are changed.

Therefore, the directions of the front wheels 11A, 11A fall within the range of the rotation limit angle when only the outer drive steering mechanism 7 is used. Next, (b) a case of special traveling (specific modes will be described later) will be described. The front wheel 11
The operation at A, 11A and the operation at rear wheels 47A, 47A are the same, and the operation at front wheels 11A, 11A will be described as an example.

Inside drive steering mechanism 5, Outside drive steering mechanism 7
Thereby, the directions of the front wheels 11A, 11A can be changed in two stages. That is, first, the hydraulic cylinder 13 is
The locked state of A and 13A is released. Subsequently, by turning the handle 53 clockwise or counterclockwise, the hydraulic cylinder 13
The inner drive steering mechanism 5 is turned horizontally by A and 13A. The front wheel side case 6B of the second front wheel drive axle 6 is rotated by the inner drive steering mechanism 5 about the inner drive steering mechanism 5, and the front wheels 11A, 11A are rotated.
At this time, the outer drive steering mechanism 7 is in a fixed state.

The inner drive steering mechanism 5 is rotated and stopped at the maximum angle, becomes a fixed state, and the rotation angle of the second front wheel drive axle 6 reaches the limit angle. The front wheels 11A, 11A are turned by a predetermined angle (the limit angle when only the inner drive steering mechanism 5 is used). Subsequently, one front wheel side steering arm 12 is rotated. The rotation of one of the front wheel side steering arms 12 is transmitted to the outer drive steering mechanism 7, and the front wheels 11A, 11A further rotate.

The one front wheel-side steering arm 12
Is transmitted from one outer drive steering mechanism 7 → first front wheel side tie rod 15 → front wheel side link 14 → second front wheel side tie rod 16 → the other outer drive steering mechanism 7, and one outer drive The turning mechanism 7 and the other outer drive turning mechanism 7 are simultaneously operated. As a result, the left and right front wheels 11
The directions of A and 11A are the same.

Thus, the directions of the front wheels 11A, 11A can be changed in two stages. The maximum change angle of the front wheels 11A, 11A depends on the rotation of the second front wheel drive axle 6
This is the sum of the angle of change θ1 of 1A, 11A and the angle of change θ2 of front wheels 11A, 11A with respect to the second front wheel drive axle 6. FIG. 6 shows an example in which the sum of the change angle θ1 of the front wheels 11A, 11A and the change θ2 of the front wheels 11A, 11A is 90 degrees.

Here, as an example of the special traveling (b), there are the following modes (1), (2) and (3), for example. (1) FIG. 7 shows front wheels 11A, 11A and rear wheels 47A, 4
7A shows a mode in which the front and rear wheel steering all-wheel drive vehicle 1 is run with both the front wheels 11A and 11A and the rear wheels 47A and 47A pointing in the same direction, with both of the wheels 7A facing sideways. In this aspect,
The front wheels 11A, 11A and the rear wheels 47A, 47A are driven by rotation in the same direction. By running the front-rear-wheel steering all-wheel drive vehicle 1 at right angles, it is possible to easily put the vehicle 1 in and out of the garage 54.

(2) FIG. 8 shows a mode in which both the front wheels 11A, 11A and the rear wheels 47A, 47A are directed in the horizontal direction, and the front-rear-wheel steering all-wheel drive vehicle 1 is turned around the center thereof. . In this embodiment, the front wheels 11A, 11A and the rear wheels 47A, 47A are driven in reverse rotation. (3) FIG. 9 shows a mode in which the front wheels 11A, 11A are turned sideways and the front-rear-wheel steering all-wheel drive vehicle 1 is turned around the rear side. In this embodiment, the front wheels 11A, 11A
Are driven, and the rear wheels 47A, 47A are not driven, but are rotated, for example, by setting the rear transmission portion of the power distribution device (not shown) to a neutral state. Also, rear wheel 4
The front and rear wheel steering all-wheel drive vehicle 1 can be turned around the front side with the 7A and 47A directed sideways.

According to the above arrangement, the front wheels 11 are controlled by the inner drive steering mechanisms 5, 5 and the outer drive steering mechanisms 7, 7.
A, 11A and the direction of at least one of the rear wheels 47A, 47A can be changed in two stages. Therefore, the front wheels 11A, 11A and the rear wheels 47A, 47A are caused to travel, for example, in a direction perpendicular to the traveling direction of the vehicle, or the front-rear-wheel steering all-wheel drive vehicle 1 is caused to make a turning motion about the center thereof. be able to.

As a result, small turnability of the front-rear-wheel-steering all-wheel drive vehicle 1 at a narrow construction site is ensured, and it becomes possible to perform width-shifting, putting in and out of the garage 54 by running at a right angle, U-turn, and the like. Normal traveling or special traveling can be selected for the front-rear-wheel-steering all-wheel drive vehicle 1 and can be properly used depending on road conditions. In the present embodiment, an example is shown in which the front-rear-wheel steering all-wheel drive vehicle 1 is applied to a crane vehicle. However, it is needless to say that the present invention can be applied to vehicles other than the crane vehicle.

Also, in this embodiment, the front and rear wheels according to the embodiment of the invention described in claim 2 are examples of using the drive unit for sharp-angle steering according to the embodiment of the invention described in claim 1. Although a steering all-wheel drive type vehicle has been described,
The drive unit for steep angle steering can be mounted only on the front wheel side, or can be mounted only on the rear wheel side. Further, in the present embodiment, a description will be given by taking as an example a case where the front wheel side drive device is comprised of one steep angle steering drive unit and the rear wheel side drive device is comprised of one steep angle steering drive unit. However, the front wheel-side drive device may be constituted by a plurality of drive units for sharp-angle steering, and the rear wheel-side drive device may be constituted by a plurality of drive units for sharp-angle steering. That is, the front wheel side may have a plurality of axes, and the rear wheel side may have a plurality of axes.

In the present embodiment, the front wheel side operation means 13 is composed of the hydraulic cylinders 13A, 13A. However, the invention is not limited to such a means, and may be a drag link. In addition, in the present embodiment, the rear wheel side operation means 49 is provided with hydraulic cylinders 49A, 49A.
A, but is not limited to such means, and may be a drag link.

In this embodiment, the inner drive steering mechanism uses a spherical joint. However, the present invention is not limited to this type. For example, a cross joint may be used. Can also. Alternatively, in the present embodiment, the outer drive steering mechanism uses a type using a spherical joint. However, the present invention is not limited to such a type, and for example, a cross joint may be used.

Further, in this embodiment, FIG. 6 shows the change angle θ1 of the front wheels 11A, 11A and the front wheels 11A, 1A.
Although an example is shown in which the sum of the change angles θ2 of 1A is 90 degrees, the present invention is not limited to 90 degrees.

[0048]

According to the first aspect of the present invention, the inner drive steering mechanism and the outer drive steering mechanism control the tire direction to two.
By changing the stage, the direction of the tire can be increased.

According to the second aspect of the present invention, the direction of at least one of the front wheels and the rear wheels can be changed in two stages by the inner drive steering mechanism and the outer drive steering mechanism.
Therefore, for example, the front wheel and the rear wheel can be rotated in a direction perpendicular to the vehicle traveling direction to enable the vehicle to travel at a right angle, or to perform a turning motion around the center of the front-rear wheel steering all-wheel drive type vehicle. . As a result, small turnability at a narrow construction site can be ensured, and it is possible to perform width shifting, putting in and out of the garage by running at right angles, and U-turning.

[Brief description of the drawings]

FIG. 1 is a partial front cross-sectional view showing a front wheel side of a front-rear-wheel steering all-wheel drive vehicle according to an embodiment of the present invention.

FIG. 2 is a plan view showing a front wheel side of the front and rear wheel steering all-wheel drive vehicle.

FIG. 3 is an enlarged partial cross-sectional view showing a right half of FIG. 1;

FIG. 4 is a partial front sectional view showing a rear wheel side of the front and rear wheel steering all-wheel drive vehicle.

FIG. 5 is a plan view showing a rear wheel side of the front and rear wheel steering all-wheel drive type vehicle.

FIG. 6 is an explanatory plan view showing the entire front and rear wheel steering all-wheel drive vehicle.

FIG. 7 is an explanatory plan view of lateral running of the front and rear wheel steering all-wheel drive vehicle.

FIG. 8 is an explanatory plan view of a turning motion of the front-rear-wheel steering all-wheel drive vehicle.

FIG. 9 is an explanatory plan view of the turning motion of the front and rear wheel steering all-wheel drive vehicle.

FIG. 10 is an explanatory plan view showing a conventional front-rear-wheel steering all-wheel drive vehicle.

FIG. 11 is an explanatory plan view showing a state in which front and rear wheels of a conventional front-rear-wheel steering all-wheel drive vehicle are turned.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 front and rear wheel steering all-wheel drive vehicle 2 front wheel side drive device 2A drive unit for steep angle turning 3 rear wheel side drive device 3A drive unit for steep angle turning 4 first front wheel drive axle 4A first front wheel drive shaft 4B Front wheel differential case 5 Inside drive steering mechanism 6 Second front wheel drive axle 6A Second front wheel drive shaft 6B Second front wheel side case 7 Outside drive steering mechanism 12 Front wheel side steering arm 13 Front wheel side operation means 14 Front wheel side link 15 First front wheel side tie rod 16 Second front wheel side tie rod 40 First rear wheel drive axle 40A First rear wheel drive shaft 40A Rear wheel differential case 41 Inner drive steering mechanism 42 Rear wheel drive axle 42A Second rear wheel drive Shaft 42B Rear wheel side case 43 Outside drive steering mechanism 48 Rear wheel side steering arm 49 Rear wheel side operating means 51 First rear wheel side tyro De 52 second rear-wheel-side tie rod

Claims (2)

[Claims] A first drive shaft that is rotated by a drive force transmitted from an engine and is housed in a differential case;
A driving axle, a pair of inner drive steering mechanisms each having one side connected to both sides of the first drive axle, and one side connected to the other side of each inner drive steering mechanism,
A pair of second drive axles accommodating a second drive shaft in a side case, and one pair of outer sides each connected to the other side of each of the second drive axles to transmit driving and steering to the tires A drive steering mechanism; a steering arm provided on one of the outer drive steering mechanisms; operating means for rotating each of the second drive axles in a horizontal direction; and a horizontal direction on a differential case of the first drive axle. A first tie rod connected to one end of the link and one outer drive steering mechanism, and a second tie rod connected to the other end of the link and the other outer drive steering mechanism. A drive unit for steep angle steering, comprising a tie rod. 2. A front wheel side drive device having one or more steep angle turning drive units and a rear wheel side drive device having one or more steep angle turning drive units, wherein a front wheel side steep angle is provided. The steering drive unit includes a first front wheel drive axle in which a first front wheel drive shaft rotated by a driving force transmitted from an engine is accommodated in a front wheel differential case, and a first front wheel drive axle on each side. A pair of inner drive steering mechanisms having one side connected thereto, and one side connected to the other side of each inner drive steering mechanism,
A pair of second front wheel drive axles each accommodating a second front wheel drive shaft in a front wheel side case, and one side is connected to the other side of each second front wheel drive axle to drive and steer the front wheels. A pair of outer drive steering mechanisms for transmitting, a front wheel steering arm provided in one outer drive steering mechanism, front wheel operating means for rotating each second front wheel drive axle in the horizontal direction, A front wheel link rotatably mounted on a front wheel differential case of the front wheel drive axle, a first front wheel tie rod connected to one end of the front wheel link and one outer drive steering mechanism, A second front wheel-side tie rod connected to the other end and the other outer drive steering mechanism, wherein the rear wheel-side steep-angle steering drive unit rotates by a driving force transmitted from the engine; Rear wheel drive shaft A first rear wheel drive axle housed in a differential case, a pair of inner drive steering mechanisms each having one side connected to both sides of the first rear wheel drive axle, and the other side of each inner drive steering mechanism One side is connected to each,
A pair of second rear wheel drive axles each accommodating a second rear wheel drive shaft in a rear wheel side case; one side connected to the other side of each second rear wheel drive axle; A pair of outer drive steering mechanisms for transmitting drive and steering, a rear wheel-side steering arm provided on one outer drive steering mechanism, and each of the second rear wheel drive axles are horizontally rotated. A rear wheel side operating means, a rear wheel side link rotatably mounted on a rear wheel differential case of the first rear wheel drive axle, and one end of the rear wheel side link and one outer drive steering mechanism connected to the rear wheel side link; A first rear wheel side tie rod, and a second rear wheel side tie rod connected to the other end of the rear wheel side link and the other outer drive steering mechanism. Driven vehicle.