JP2023092161A - Auxiliary wheel device for caster - Google Patents

Abstract

To provide an auxiliary wheel device for a caster which can achieve space-saving when arranging a caster and an auxiliary wheel.SOLUTION: An auxiliary wheel device for a caster comprises: a caster which rotates in a travel direction of a vehicle body and in which steering angle is freely changed when the vehicle body turns; and an auxiliary wheel which is arranged in front of or in the rear of the caster in the travel direction, and arranged at the height where the auxiliary wheel is not grounded when the caster is grounded. The caster does not interfere with the auxiliary wheel at the initial position of the auxiliary wheel, and the steering angle is changed when the auxiliary wheel is grounded so that the caster does not interfere with the auxiliary wheel.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present disclosure relates to a training wheel device for casters.

Patent Literature 1 discloses a vehicle equipped with auxiliary wheels in front of and behind the wheels for assisting the vehicle in going over bumps.

JP-A-5-131949

In a vehicle equipped with auxiliary wheels, consider a case where, for example, instead of the wheels, casters are used, the steering angle of which can be freely rotated when the vehicle body turns. In this case, it is necessary to set a wide installation interval between the casters and the training wheels so that they do not interfere with each other, which increases the mounting space for each part. Therefore, there is a demand for a technique capable of saving space in such a case.

The present disclosure has been made in view of the above, and an object of the present disclosure is to provide a caster training wheel device capable of saving space when arranging casters and training wheels.

A caster auxiliary wheel device according to the present disclosure includes a caster that rotates in the traveling direction of a vehicle body and that freely rotates at a steering angle when the vehicle body turns, and is provided in front or behind the caster in the traveling direction, and an auxiliary wheel provided at a height that is in a non-grounded state when the caster touches the ground, and the caster does not interfere with the auxiliary wheel at the initial position of the auxiliary wheel and does not interfere with the auxiliary wheel when the auxiliary wheel touches the ground. , the rudder angle is rotated so as to be at a position where it does not interfere with the auxiliary wheels.

According to the present disclosure, it is possible to save space when arranging casters and training wheels.

FIG. 1 is a side view showing a schematic configuration of a caster training wheel device according to an embodiment. FIG. 2 is a side view showing a state of casters and training wheels when the vehicle body moves forward in the caster training wheel device according to the embodiment. FIG. 3 is a side view showing a state of casters and training wheels when the vehicle body moves backward in the caster training wheel device according to the embodiment. FIG. 4 is a plan view for explaining the rotation trajectory of the caster in the caster training wheel device according to the embodiment. FIG. 5 is a side view for explaining the rotation trajectory of the training wheels in the training wheel device for casters according to the embodiment. FIG. 6 is a plan view showing an example in which slopes are provided on training wheels in a modification of the training wheel device for casters according to the embodiment. FIG. 7 is a plan view showing an example of a case where the caster is locked in the modified example of the caster training wheel device according to the embodiment. FIG. 8 is a plan view showing an example of a case in which a pair of training wheels having slopes are arranged so as to be inclined with respect to the traveling direction in a modified example of the training wheel device for casters according to the embodiment.

A caster training wheel device according to an embodiment of the present disclosure will be described with reference to the drawings. Components in the following embodiments include components that can be easily replaced by those skilled in the art, or components that are substantially the same.

(Structure of auxiliary wheel device for caster)
A configuration of a caster training wheel device according to an embodiment will be described with reference to FIGS. 1 to 5. FIG. A caster auxiliary wheel device is mounted, for example, on a mobile object such as a small four-wheeled mobility vehicle, and assists the vehicle in getting over bumps on the road surface. In addition to the small four-wheeled mobility, the mobile body may be a medium-sized or large-sized mobility, or a two-wheeled mobility.

As shown in FIG. 1, the caster auxiliary wheel device 1 is attached to the lower portion (bottom portion) of a vehicle body 2 of a moving body. For example, when the moving object is a four-wheel mobility vehicle, the auxiliary wheel devices 1 for casters are attached to the left and right sides of the vehicle body 2, respectively.

The caster training wheel device 1 includes a caster 11 and training wheels 12 and 13 . The caster training wheel device 1 may include only one of the training wheels 12 and 13 .

The caster 11 functions as a driven wheel of the moving body. Wheels 3 functioning as driving wheels of the moving body are attached to the lower portion of the vehicle body 2 and in front of the casters 11 (on the left side of the drawing). Thus, by using the wheels 3 as driving wheels and the casters 11 as driven wheels, the casters 11 rotate while being driven by the driving force and turning torque generated by the wheels 3 as the driving wheels.

The movable body to which the caster auxiliary wheel device 1 is applied can move forward and backward. In this embodiment, with respect to the direction of movement of the moving object, the forward direction (leftward on the paper surface of FIG. 1) is defined as "forward" and the backward direction (leftward on the paper surface of FIG. 1) is defined as "rearward." .

As shown in FIG. 1, the casters 11 are configured to rotate in the traveling direction of the vehicle body 2 and freely rotate at a steering angle when the vehicle body 2 turns. The caster 11 includes a support member 111 and wheels 112 attached to the support member 111, as shown in FIG.

The support member 111 is made of a metal material or the like capable of supporting the weight of the vehicle body 2 and the wheels 112 . The diameter of the wheel 112 is configured to be smaller than the diameter of the wheel 3 of the driving wheel, for example, as shown in FIG.

The auxiliary wheels 12 are for assisting the moving object to get over bumps on the road surface when moving forward. The auxiliary wheels 12 are provided in front of the casters 11 in the traveling direction of the mobile object. Further, the auxiliary wheel 12 includes a support member 121, a wheel 122, and an elastic member 123, as shown in FIG.

The support member 121 is made of a metal material or the like capable of supporting the weight of the vehicle body 2 and the wheels 122 . The wheels 122 are provided at a height H that is in a non-grounded state when the wheels 112 of the caster 11 are grounded (see FIG. 1). That is, the wheels 122 are attached to the vehicle body 2 so as not to contact the road surface when the wheels 3 as driving wheels and the casters 11 as driven wheels are in contact with the road surface. The height H of the wheels 122 with respect to the road surface is set within a range of 10 to 20% of the diameter of the casters 11, for example.

As shown in FIG. 2, the wheels 122 are configured so as to come into contact with the step when the moving body goes over the step on the road surface. In this way, when the wheel 122 of the auxiliary wheel 12 goes up the step first when going over the step, the step where the caster 11 goes up becomes the height difference between the wheel 122 and the caster 11 . Therefore, even if the diameter of the wheel 112 of the caster 11 is smaller than the diameter of the wheel 3 of the driving wheel, it is possible to cope with a large level difference. In this embodiment, as shown in FIGS. 1 and 3, the "initial position" of the wheels 122 (the auxiliary wheels 12) is defined as the case where the wheels 122 are not in contact with the road surface.

The wheel 122 has a circular shape with a part cut away when viewed from the side as shown in FIGS. Further, the wheels 122 are arranged so that the surfaces of the casters 11 that do not face the wheels 112 are curved in the initial position of the auxiliary wheels 12 shown in FIG.

In this way, by making the shape of the wheel 122 a circular shape with a part cut away, the auxiliary wheel 12 does not move on a flat road surface. can be ensured.

In addition, by making the shape of the wheel 122 into a shape in which a part of a circle is notched, as shown in FIG. The distance D1 and the distance D2 between the auxiliary wheels 12 and 13 can be reduced. Specifically, by making the shape of the wheel 122 fan-shaped, the gaps D1 and D2 can be reduced by the radius of the wheel 122 compared to when the shape of the wheel is circular.

In addition, the shape of the wheel 122 when viewed from the side may be at least a shape in which a part of the circle is notched. Therefore, instead of the fan shape shown in FIG. 1, that is, the shape having a central angle of less than 180°, the shape may have, for example, a central angle of 180° or more. In this way, the wheel 122 has a partially notched circular shape as viewed from the side and has a central angle of 180° or more, thereby increasing the rotation angle of the wheel 122. be able to. As a result, it is possible to get over a larger step on the road surface.

The elastic member 123 is for biasing the wheel 122 . The elastic member 123 is attached across the support member 121 and the wheel 122, and biases the wheel 122 so that the wheel 122 returns to its initial position (see FIG. 3). By applying the biasing force of the elastic member 123 to the wheel 122 in this manner, the wheel 122 is arranged such that the surface of the caster 11 that does not face the wheel 112 is curved in the initial position.

The auxiliary wheels 13 are for assisting the moving object to get over bumps on the road surface when moving backward. The auxiliary wheels 13 are provided behind the casters 11 in the traveling direction of the mobile object. Further, the auxiliary wheel 13 includes a support member 131, a wheel 132, and an elastic member 133, as shown in FIG.

The support member 131 is made of a metal material or the like capable of supporting the weight of the vehicle body 2 and the wheels 132 . The wheels 132 are provided at a height H that is in a non-grounded state when the wheels 112 of the caster 11 are grounded (see FIG. 1). That is, the wheels 132 are attached to the vehicle body 2 so as not to contact the road surface when the wheels 3 as driving wheels and the casters 11 as driven wheels are in contact with the road surface. The height H of the wheel 132 with respect to the road surface is set within a range of 10 to 20% of the diameter of the caster 11, for example.

As shown in FIG. 3, the wheels 132 are configured to come into contact with the bumps on the road surface when the moving body goes over the bumps in reverse. In this way, when the wheel 132 of the auxiliary wheel 13 goes up the step first when going over the step, the step that the caster 11 goes up becomes the height difference between the wheel 132 and the caster 11 . Therefore, even if the diameter of the wheel 112 of the caster 11 is smaller than the diameter of the wheel 3 of the driving wheel, it is possible to cope with a large level difference. In this embodiment, as shown in FIGS. 1 and 2, the "initial position" of the wheel 132 (the auxiliary wheel 13) is defined as the case where the wheel 132 is not in contact with the road surface.

The wheel 132 has a circular shape with a part cut away when viewed from the side as shown in FIGS. Further, the wheels 132 are arranged so that the surfaces of the casters 11 that do not face the wheels 112 are curved in the initial position of the auxiliary wheels 13 shown in FIG.

In this way, by making the shape of the wheel 132 a circular shape with a part cut away, the auxiliary wheel 13 does not move on a flat road surface. can be ensured.

In addition, by making the shape of the wheel 132 into a shape in which a part of the circle is notched, compared with the case where the shape of the wheel 132 is circular, as shown in FIG. , and the distance D2 between the auxiliary wheel 13 and the auxiliary wheel 12 can be reduced. Specifically, by making the shape of the wheel 132 fan-shaped, the gaps D1 and D2 can be reduced by the radius of the wheel 132 compared to the case where the shape of the wheel is circular.

In addition, the shape of the wheel 132 when viewed from the side may be at least a shape in which a part of the circle is notched. Therefore, instead of the fan shape shown in FIG. 1, that is, the shape having a central angle of less than 180°, the shape may have, for example, a central angle of 180° or more. In this way, the wheel 132 has a partially notched circular shape as viewed from the side and has a central angle of 180° or more, thereby increasing the rotation angle of the wheel 132. be able to. As a result, it is possible to get over a larger step on the road surface.

The elastic member 133 is for biasing the wheel 132 . The elastic member 133 is attached across the support member 131 and the wheel 132, and biases the wheel 132 so that the wheel 132 returns to its initial position (see FIG. 2). By applying the biasing force of the elastic member 133 to the wheel 132 in this manner, the wheel 132 is arranged so that the surface of the caster 11 that does not face the wheel 112 is curved in the initial position.

In the caster training wheel device 1 configured as described above, the caster 11 and the training wheels 12 and 13 have the following features. First, the caster 11 is configured so as not to interfere with the auxiliary wheels 12 and 13 at the initial position of the auxiliary wheels 12 (see FIG. 3) and the initial position of the auxiliary wheels 13 (see FIG. 2).

Further, the steering angle of the caster 11 is rotated so that the caster 11 is positioned so as not to interfere with the auxiliary wheels 12 and 13 when the auxiliary wheels 12 and 13 touch the ground. For example, when the front auxiliary wheel 12 touches a step (see FIG. 2), the caster 11 rotates rearward without interfering with the auxiliary wheel 12, that is, toward the auxiliary wheel 13 side. On the other hand, when the rear auxiliary wheel 13 touches a step (see FIG. 3), the caster 11 rotates forward without interfering with the auxiliary wheel 13, that is, toward the auxiliary wheel 13 side.

Also, the caster 11 and the auxiliary wheels 12 and 13 are arranged at positions where their rotational trajectories interfere with each other. Here, FIG. 4 is a plan view showing an example of the rotation locus T1 of the caster 11. As shown in FIG. FIG. 5 is a side view showing an example of the rotation locus T2 of the front auxiliary wheel 12. As shown in FIG.

In the caster auxiliary wheel device 1, the caster 11 and the auxiliary wheel 12 are arranged at positions where the rotational locus T1 of the caster 11 and the rotational locus T2 of the auxiliary wheel 12 interfere with each other. However, as shown in FIG. 2, when the auxiliary wheels 12 come into contact with a step while moving forward, the casters 11 rotate backward so as not to interfere with the auxiliary wheels 12. The auxiliary wheels 12 do not actually interfere. The same applies to the relationship between casters 11 and training wheels 13 .

That is, in the caster auxiliary wheel device 1, the caster 11 and the auxiliary wheel 13 are arranged at positions where the rotational locus T1 of the caster 11 and the rotational locus of the auxiliary wheel 13 interfere with each other. However, as shown in FIG. 3, when the auxiliary wheels 13 come into contact with a step while the moving object is moving backward, the casters 11 rotate forward so as not to interfere with the auxiliary wheels 13. Therefore, when the moving object moves backward, the casters 11 and The auxiliary wheels 13 do not actually interfere.

Further, in the caster auxiliary wheel device 1, as shown in FIG. 4, it is preferable that the casters 11 and the auxiliary wheels 12 are arranged linearly along the moving direction of the moving body. Although not shown in the figure, the casters 11 and the auxiliary wheels 13 are also preferably arranged linearly along the moving direction of the moving body. By arranging the casters 11 and the auxiliary wheels 12 and 13 linearly along the traveling direction of the moving body in this way, it is possible to achieve further space saving as compared to the case where they are not arranged linearly. .

In the caster training wheel device according to the embodiment described above, in the initial positions of the training wheels 12 and 13 (see FIGS. 1 to 3), the caster 11 does not interfere with the training wheels 12 and 13, and the training wheels 12 and 13 do not interfere with each other. When 13 touches the ground, the caster 11 rotates so as not to interfere with the auxiliary wheels 12 and 13 .

Further, by making the shape of the auxiliary wheels 12 and 13 (wheels 122 and 132) into a circular shape with a part cut away, the auxiliary wheels 12 and 13 are more compact than when the auxiliary wheels are circular in shape. and the caster 11, and the distance D2 between the auxiliary wheel 12 and the auxiliary wheel 13 can be reduced. As a result, space can be saved when the casters 11 and the auxiliary wheels 12 and 13 are arranged.

(Modification)
Modifications of the caster training wheel device 1 according to the embodiment will be described with reference to FIGS. 4 to 8. FIG.

The caster 11 of the caster auxiliary wheel device 1 is configured so that the steering angle can be freely rotated when the vehicle body 2 turns. Therefore, for example, when the casters 11 and the auxiliary wheels 12 are arranged in a straight line along the traveling direction of the moving object (see FIG. 4), when the casters 11 and the auxiliary wheels 12 are not grounded when the moving object moves forward and climbs over a step, rotates and may come into contact with the training wheel 12 in some cases. When the casters 11 and the auxiliary wheels 12 come into contact with each other in this way, the rotation of the casters 11 is locked, and the behavior of the vehicle body 2 becomes unstable.

Therefore, in a modified example of the auxiliary wheel device 1 for casters, auxiliary wheels 12A are used instead of the auxiliary wheels 12, as shown in FIG. The wheels 122 of the training wheels 12A are configured to have a wider width than the wheels 122 of the training wheels 12A. Further, in the auxiliary wheels 12A, the wheels 122 have slopes 124 that are not parallel to the traveling direction of the moving body. Specifically, the slope 124 is formed by offsetting the position where the rotation trajectory T1 (see FIG. 4) of the caster 11 and the rotation trajectory T2 (see FIG. 5) of the auxiliary wheel 12A interfere with each other in the wheel 122. be done.

In this way, by using the auxiliary wheels 12A having the slopes 124, when the casters 11 and the auxiliary wheels 12A come into contact with each other while moving forward over a step, the slopes 124 force the casters 11 backward. can be rotated. As a result, locking of the rotation of the casters 11 by the auxiliary wheels 12A can be suppressed, and the behavior of the vehicle body 2 can be stabilized.

Although only the front auxiliary wheel 12A has been described in FIG. 6, the wheel 132 of the auxiliary wheel 13 may also be provided with a slope that is not parallel to the traveling direction of the moving body. As a result, when the caster 11 and the auxiliary wheel 13 come into contact with each other while driving backward over a step, the caster 11 can be forcibly rotated forward by the slope. As a result, locking of rotation of the casters 11 by the auxiliary wheels 13 can be suppressed, and the behavior of the vehicle body 2 can be stabilized.

Here, as shown in FIG. 7, even when the auxiliary wheel 12A having the slope 124 is used, the caster 11 may come into contact with the portion of the auxiliary wheel 12A other than the slope 124 depending on the rotation timing of the caster 11. As a result, the rotation of the caster 11 may be locked.

In this case, for example, as shown in FIG. 8, it is preferable to dispose the auxiliary wheels 12A at an angle with respect to the traveling direction of the moving body. In the example shown in the figure, the center axis of rotation of the auxiliary wheel 12A is arranged with being inclined outward. Also, when the moving body is a four-wheeled mobility vehicle, as shown in FIG. As a result, the moving body can move straight along the traveling direction.

In this way, by using the auxiliary wheels 12A having slopes 124 and oppositely set inclination angles on the left and right sides, locking of the rotation of the casters 11 by the auxiliary wheels 12A can be more reliably suppressed, and the vehicle body can be 2 can be stabilized.

Although only the front auxiliary wheel 12A has been described in FIG. 8, the wheel 132 of the auxiliary wheel 13 is also provided with a slope that is not parallel to the traveling direction of the moving body, and the inclination angle is set opposite to the left and right. good too. As a result, locking of the rotation of the casters 11 by the auxiliary wheels 13 can be more reliably suppressed, and the behavior of the vehicle body 2 can be stabilized.

Further advantages and modifications can be easily derived by those skilled in the art. Therefore, the broader aspects of the invention are not limited to the specific details and representative embodiments shown and described above. Accordingly, various changes may be made without departing from the spirit or scope of the general inventive concept defined by the appended claims and equivalents thereof.

1 Caster Auxiliary Wheel Device 11 Caster 111 Supporting Member 112 Wheel 12, 12A, 13 Auxiliary Wheel 121, 131 Supporting Member 122, 132 Wheel 123, 133 Elastic Member 124 Slope 2 Body 3 Wheel D1, D2 Spacing H Height T1, T2 locus of rotation

Claims (5)

a caster that rotates in the traveling direction of the vehicle body and that freely rotates at a steering angle when the vehicle body turns;
an auxiliary wheel provided in front or behind the caster in the direction of travel, and provided at a height at which the caster is in a non-grounded state when the caster touches the ground;
with
The casters are
At the initial position of the training wheel, it does not interfere with the training wheel,
The steering angle rotates so that when the training wheels touch the ground, the steering angle is positioned so as not to interfere with the training wheels.
Training wheel device for casters. The caster and the auxiliary wheel are arranged at positions where their rotational trajectories interfere with each other.
The auxiliary wheel device for casters according to claim 1. The auxiliary wheel has a sector shape in which a surface that does not face the caster is curved in the initial position,
The auxiliary wheel device for casters according to claim 1 or 2. The casters and the auxiliary wheels are arranged linearly along the traveling direction,
The auxiliary wheel device for a caster according to any one of claims 1 to 3. The auxiliary wheel has a slope that is not parallel to the traveling direction,
The auxiliary wheel device for a caster according to any one of claims 1 to 4.

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