JPH106794A - Trackless vehicle with double tires - Google Patents

Abstract

(57) [Summary] [Problem] To use double tires to reduce the load burden,
Driving force loss caused by the difference in the number of rotations of the inner and outer wheels is reduced. SOLUTION: Differential transmission of power transmission is performed by a differential mechanism 12 on both sides in the axial direction of a rigid axle 11, and a difference between an inner wheel and an outer wheel of a driving wheel 14 at the time of turning is absorbed. Although the burden on the non-driving wheel 15 that constitutes a double tire together with the driving wheel 14 is performed in the same manner as the driving wheel 14,
Since the vehicle is in the non-driving state, a driving force loss due to a difference in inner and outer wheels based on a difference in position between the driving wheels 14 does not occur. Even when the rigid axle 11 is turned around the axis 12a for steering, the loss for the difference between the inner and outer wheels is reduced, so that the power for steering can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a trackless vehicle provided with a double tire that supports a load with a plurality of wheels for carrying heavy objects.

[0002]

2. Description of the Related Art Double tire drive wheels are often used in luggage transport vehicles, especially dump trucks, forklifts, cargo trucks, trailers, etc., which are trackless vehicles that transport heavy objects. Trackless vehicles of the double tire system are known, for example, from Japanese Patent Publication No. 50-39288 and Japanese Utility Model 1-4.
4380 and the like.

FIG. 5 shows a configuration of a trackless vehicle of a typical double tire specification. Rigid axle 1 as drive shaft
A differential mechanism 2 is incorporated in the center of the vehicle, and an inner drive wheel 4 and an outer drive wheel 5 are mounted at both ends in the axial direction of a rigid axle 1 that supports a vehicle body 3 on which luggage is loaded so as to form a pair on the left and right. ing. Inner drive wheel 4
The outer drive wheel 5 is similarly driven to rotate, and the differential mechanism 2 can absorb a difference in rotation speed between the left and right double tires due to a difference in inner and outer wheels during turning.

[0004]

Since the rigid axle 1 shown in FIG. 5 drives the inner drive wheel 4 and the outer drive wheel 5 simultaneously, the driving force loss due to the difference between the inner and outer wheels when turning between the left and right drive wheels. Can be reduced, but the loss for the inner and outer wheel difference between the inner drive wheel 4 and the outer drive wheel 5 at each end remains.

[0005] If there is a driving force loss due to the difference between the inner and outer wheels between the driving wheels of the double tire specification at both ends of the rigid axle, it is necessary for steering when the trackless vehicle changes direction when carrying heavy objects. The force increases and a large-scale steering device is required. In addition, since the difference in the number of rotations between the inner drive wheel 4 and the outer drive wheel 5 is absorbed by the friction of the respective drive wheels against the running surface, the wear of the drive wheels also increases.

An object of the present invention is to provide a trackless vehicle having double tires that can reduce driving force loss with a simple configuration.

[0007]

According to the present invention, there is provided a rigid axle for differentially distributing power transmission to tires at both axial ends by a differential mechanism incorporated at a center,
A plurality of pairs of wheels mounted on both ends of the rigid axle in the axial direction, a driving force can be transmitted to only one pair of wheels, and the other wheels are in a non-driven state. It is a trackless vehicle equipped. According to the present invention, the driving force can be transmitted to only one pair of the wheels mounted on both ends of the rigid axle in the axial direction, and the other wheels are not driven. At the end, the difference in the number of rotations between the driven wheel and the non-driven wheel is easily absorbed, and only one pair of wheels is driven to rotate, so that the driving force loss can be reduced.

In the present invention, the rigid axle includes a steering mechanism. According to the present invention, since the rigid axle includes a steering mechanism, the force required for steering as the steering axle can be easily steered with a small force because the driving force loss between the wheels is small, and the mechanism is simplified. Therefore, it is possible to reduce the size of the trackless vehicle.

In the present invention, the other wheel is mounted via a rotary bearing. According to the present invention, the other wheels mounted in a non-driving state at both ends of the rigid axle are mounted via rotary bearings, so that the wheels are rotatable with respect to the rigid axle, and a driving force loss during turning is reduced. This can reduce the power for steering and the power for steering, and can prevent wheel wear.

[0010]

FIG. 1 shows a schematic structure of a trackless vehicle provided with a double tire according to an embodiment of the present invention. The rigid axle 11 is incorporated into a differential mechanism 12 at the center, and is mounted below the vehicle body 13.
To the differential mechanism 12, a driving force for traveling is transmitted from a driving mechanism mounted on the vehicle body 13, and differentially distributed to both sides of the rigid axle 11 in the axial direction. On both sides of the rigid axle 11 in the axial direction, a drive wheel 14 is mounted on the inside and a non-drive wheel 15 is mounted on the outside so as to form a pair. Wheel caps 16 are attached to both ends of the rigid axle 11. The drive wheel 14 is mounted on the outer periphery of a drive wheel mounting drum 17 that is mounted closer to the inside in the axial direction than the wheel cap 16. A brake cover 18 is mounted on the inner side of the driving wheel mounting drum 17 in the axial direction, and a brake for braking the driving wheel mounting drum 17 is housed therein.

In the present embodiment, the driving wheels 14 and the non-driving wheels 15 make contact with the traveling road surface 19 with double tires,
Load on one wheel. One side of the double tire is not driven, and driving force transmission is performed in half, so that driving force loss during turning can be reduced.

FIG. 2 is a plan view of the rigid axle 11 of FIG. 1, and FIG. 3 is a cross-sectional view showing a detailed structure of a portion where the double axle is attached to the rigid axle 11 of FIG. Referring to FIGS. 2 and 3, the rotational driving force distributed by differential mechanism 12 is applied to power transmission shaft 2.
It is transmitted as rotation about the central axis of zero. The power transmission shaft 20 is inserted through the inside of the housing 21, and the wheel cap 16 is attached to an axial end. The end face of the wheel cap 16 is covered by the end plate 22. The wheel cap 16 is rotatable with respect to the housing 21 via a bearing 23. The bearing 23 is attached to the end of the housing 21 by a bearing support 24 on the outer peripheral side, and the housing 21 is bolted to the inner peripheral side by a bolt 25.
Is fixed to the end. The inner cylindrical portion of the wheel cap 16 is sandwiched between the outer peripheral side and the inner peripheral side of the bearing 23, and is rotatably supported.

The drive wheel mounting drum 17 has an axially outer end face connected to the inner end face of the wheel cap 16, and receives rotational driving force from a power transmission shaft 20. The inner peripheral surface of the drive wheel mounting drum 17 is rotatably supported by the housing 21 via bearings 26 and 27. The bearing 26 is arranged near the outer end face in the axial direction, and the bearing 27 is arranged near the inner end face in the axial direction. Rim 28 of drive wheel 14
Are mounted on the driving wheel mounting drum 17 and the non-driving wheels 15
Is mounted in a non-driving state via a bearing 30. Rubber tires 31 and 32 are mounted on the rims 28 and 29, respectively.

With respect to the drive wheel mounting drum 17, a brake 33 housed in the brake cover 18 is disposed so as to be able to contact or separate from a brake shoe 34 extending inward in the axial direction from the drive wheel mounting drum 17. Have been. When the brake 33 comes into contact with the surface of the brake shoe 34 with high pressure, the driving wheel mounting drum 1
7 is braked.

FIG. 4 shows an all-wheel drive type double tire driving structure which is the basis of the structure for double tire driving shown in FIG. This configuration is an embodiment of the related art shown in FIG. 5, and portions corresponding to the configuration shown in FIG. 3 are denoted by the same reference numerals, and redundant description will be omitted. Outer drive wheel 3
5 is mounted not on the wheel cap 36 but on the driving wheel mounting drum 37, and is driven together with the inner driving wheel 14 by the rotational driving force transmitted from the power transmission shaft 20 via the wheel cap 36. The bearing 30 shown in FIG. 3 is not provided between the rim 38 of the outer driving wheel 35 and the wheel cap 36, and the rim 38 is mounted on the outer end of the driving wheel mounting drum 37 on the outside in the axial direction.

The structure for driving a double tire shown in FIG. 3 is obtained by modifying the structure of the all-wheel drive system shown in FIG.
9 is mounted on the wheel cap 16 via the bearing 30,
By supporting the non-driving wheels 15, it is possible to reduce loss of driving force and wear of the tires 31 and 32 due to the difference in the number of rotations. Further, if the rigid axle 11 can be turned around an axis 12a perpendicular to the traveling road surface 19 through the center of the differential mechanism 12 shown in FIG.
Steering can also be performed by turning around the axis 12a. When the rigid axle 11 is turned using the steering mechanism, there is no driving force loss based on the rotational speed difference between the driving wheels 14 and the non-driving wheels 15, so that the steering power can be reduced.

In the embodiment shown in FIGS. 1 to 3, the non-drive wheels 15 are attached to the outermost end of the rigid axle 11 in the axial direction.
Is mounted, and the drive wheel 14 is mounted on the inner side. However, the outer wheel may be driven and the inner wheel may be in a non-drive state. Also, rigid axle 1
Although two wheels are mounted on one side,
It is also possible to mount three or more wheels and drive only one of them. Bear the load on multiple wheels,
This is because the load per wheel can be reduced, and sufficient driving force can be transmitted by one-wheel drive for traveling.

[0018]

As described above, according to the present invention, the rigid axle is provided with a plurality of wheels at both ends in the axial direction, so that the load is received as a whole and the load per wheel is reduced. Can be. Since the driving force is transmitted to only one pair of wheels mounted on the rigid axle, it is not necessary to drive the other wheels having a rotational speed difference,
Driving force loss and wear during turning can be reduced.

Further, according to the present invention, even when a difference in the number of rotations of the inner and outer wheels occurs between a plurality of wheels during steering, only one wheel is driven, so that the force required for steering does not increase, and The burden can be reduced.

Further, according to the present invention, since the non-driven wheels are mounted via the rotary bearings, they rotate according to the external force applied from the road surface, and a rotational speed difference is generated between the wheels and the wheels to which the driving force is transmitted. Even can be absorbed by rotating bearings,
Driving force loss due to friction between the wheels and the running surface can be reduced.

[Brief description of the drawings]

FIG. 1 is a simplified front view showing a schematic configuration of a trackless vehicle provided with a double tire according to an embodiment of the present invention.

FIG. 2 is a plan view of the rigid axle 11 according to the embodiment of FIG.

FIG. 3 is a partial cross-sectional view showing a configuration for driving a double tire at an axial end of the rigid axle shown in FIG. 2;

FIG. 4 is a partial cross-sectional view showing a configuration of an all-wheel drive system which is a basis of the structure of FIG.

FIG. 5 is a simplified front view of a trackless vehicle with double wheels of the all-wheel drive system according to the prior art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Rigid axle 12 Differential mechanism 13 Body 14 Driving wheel 15 Non-driving wheel 16 Wheel cap 17 Driving wheel mounting drum 18 Brake cover 19 Running road surface 20 Power transmission shaft 21 Housing 26, 27, 30 Bearing 28, 29 Rim 31, 32 Tire 33 Brake 34 Brake shoe

Claims (3)

[Claims] 1. A rigid axle for differentially distributing power transmission to tires at both ends in an axial direction by a differential mechanism incorporated at a center, and a plurality of pairs of wheels mounted on both ends in an axial direction of the rigid axle, A trackless vehicle equipped with double tires, wherein driving force can be transmitted only to a pair of wheels, and the other wheels are not driven. 2. The trackless vehicle with double tires according to claim 1, wherein the rigid axle includes a steering mechanism. 3. The trackless vehicle equipped with a double tire according to claim 1, wherein the other wheel is mounted via a rotary bearing.