KR102002871B1 - Non-elasticity suspension structure for automated guided vehicle - Google Patents

Abstract

The present invention relates to a non-elasticity suspension structure for an automated guided vehicle, which is able to allow the automated guided vehicle, which is used for factory automation or the like, to always maintain horizontality and ground a driving shaft even if the floor is not even, and which does not have an up-and-down elasticity. According to an embodiment of the present invention, the suspension structure, which connects a chassis on a lower side of the automated guided vehicle to a drive wheel assembly, comprises: a vertical guide member which supports the pair of drive wheel assemblies to be vertically movable against the chassis; a rotary shaft which is fixated on the chassis to be rotatable; and a first cam member and a second cam member, which are eccentrically engaged with the rotary shaft to rotate together with the rotary shaft, and whose outer circumferential surface comes in contact with an upper end surface of each of the drive wheel assemblies. The direction, in which the first cam member is eccentric from the center of the rotary shaft, is the opposite to the direction, in which the second cam member is eccentric from the center of the rotary shaft.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a non-elasticity suspension structure for an automatic traveling vehicle,

The present invention relates to a suspension structure in which automatic running vehicles used in factory automation and the like are always kept in a horizontal position and a grounded state of the drive shaft despite the uneven floor, and having no vertical elasticity.

Automated vehicles are used in plant automation systems, warehouse automation systems, and the like to receive input signals from the control unit of the system and transfer unattended loads relatively far away.

Tracking the position and running of the vehicle is very important in the operation of the autonomous vehicle. To this end, a control structure is designed to receive vehicle information from a plurality of sensors and perform feedback control.

Nevertheless, there are a variety of external factors that make it difficult to operate an automatic vehicle, one of which is uneven. This problem can be particularly easily encountered in the case of converting a conventional factory to an unmanned automation factory. Also, at the factory, which is initially leveled, it is possible that the flatness of the floor is deteriorated due to several changes of facilities and aging of the floor.

There is a problem that some of the wheels are floated when the automatic traveling vehicle travels on a floor which is not flat and there is a problem that the running direction is broken if the excited wheels are connected to the driving shaft. In view of the fact that it operates to get close to the minimum distance with other obstacles while making the most of rapid speeds, this problem increases the possibility of collision with structures or other vehicles.

On the other hand, the automatic traveling vehicle is moved up and down by an automation robot. In order to always maintain a constant height, it is preferable not to use an elastic suspension unlike a general passenger vehicle.

Korean Patent Publication No. 10-2013-0041940 (Apr. 25, 2013) U.S. Patent No. 5,344,276 (Sep. 6, 1994)

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a suspension of an automatic traveling vehicle which is capable of grounding a wheel connected to a driving shaft even though the floor is not flat,

Other objects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description.

According to an aspect of the present invention, there is provided a suspension structure for connecting a drive wheel assembly to a chassis below an autonomous vehicle, wherein a pair of the drive wheel assemblies are vertically movably supported with respect to the chassis, A first cam member eccentrically coupled to the rotation shaft and rotatable together with the rotation shaft, the first cam member contacting an outer circumferential surface of the upper surface of each of the drive wheel assemblies; Wherein the first cam member is eccentric from the center of the rotation shaft and the second cam member is eccentric from the center of the rotation shaft, .

Furthermore, the first cam member and the second cam member may have a disk shape having a circular cross section, and an outer circumferential surface portion contacting the upper end of the drive wheel assembly may be supported by a bearing.

Meanwhile, the first cam member and the second cam member may be in the shape of a disc having an elliptical cross section.

A support block is protruded on the upper part of the drive wheel assembly. A passage hole through which the support block passes is formed in the chassis. The rotation shaft, the first cam member, and the second cam member are mounted on the upper part of the chassis And can support the upper surface of the support block protruding above the upper surface of the chassis.

Further, the vertical guide member may be a plurality of LM guides fixed to the chassis, and a rod extending freely from the housing is fixed to the drive wheel assembly.

According to another embodiment of the present invention, there is provided a suspension structure for connecting a chassis of a lower portion of an autonomous vehicle with a drive wheel assembly, comprising: a vertical guide member for supporting a pair of the drive wheel assemblies so as to be vertically movable with respect to the chassis; A pinion which is coupled to both ends of the rotary shaft and is rotatable integrally with the rotary shaft, and a pinion which is coupled to each of the drive wheel assemblies and integrally moves up and down with the drive wheel assembly, And the rack members of the drive wheel assemblies are symmetrical with respect to the axis center of the rotary shaft, and the lifting operation of the drive wheel assemblies is opposed to each other The non-elasticity of the automatic traveling vehicle It presents the structure's pension.

According to the embodiment of the present invention, even if the floor is not flat, the driving wheels of the automatic driving vehicle completely come into contact with the floor, so that the intended driving of the automatic driving vehicle is possible. Furthermore, since the vehicle is kept horizontal, the tilting can be minimized and the departure of the load can be prevented. In addition, the drive wheel assembly supporting the vehicle is inelastic so that there is no change in the height of the vehicle when the cargo is loaded and unloaded, thereby enabling efficient operation of the upside-down robot.

The effects of the present invention will be clearly understood and understood by those skilled in the art, either through the specific details described below, or during the course of practicing the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a non-elastic suspension structure of an automatic traveling vehicle according to an embodiment of the present invention. FIG.
2 is a rear view of the suspension structure according to the embodiment shown in Fig.
Figure 3 is a simplified perspective view of the embodiment shown in Figure 2;
Fig. 4 is a side view showing the left part of (a) and the right part of (b) of the embodiment shown in Fig. 2;
5 is a view showing a use state of the embodiment shown in Fig.
Figure 6 shows another use state of the embodiment shown in Figure 2;
7 is a side view showing a cam member employed in another embodiment of the present invention.
FIG. 8 is a plan view schematically showing an aeroelastic suspension structure of an automatic traveling vehicle according to another embodiment of the present invention; FIG.
FIG. 9 is a perspective view schematically showing a non-elastic suspension structure of an automatic traveling vehicle according to another embodiment of the present invention. FIG.
10 is a side view showing the left part of (a) and the right part of (b) of the embodiment shown in FIG. 9;

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the configuration, functions, and functions of a non-elastic suspension structure of an automatic traveling vehicle according to the present invention will be described with reference to the accompanying drawings. It should be noted, however, that the drawing numbers for the same or similar components throughout the drawings and embodiments shall be used collectively.

In the following description, terms such as 'first', 'second', and the like are used to distinguish constituent elements whose technical meaning is within the same range for convenience. That is, any one configuration may be arbitrarily referred to as a 'first configuration' or a 'second configuration'.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, therefore, are not to be construed as limiting the technical spirit of the invention. It is to be understood that the invention is not to be limited by any of the details of the description to those skilled in the art from the standpoint of a person skilled in the art that any or all of the drawings shown in the drawings are not necessarily the shape,

In addition, some of the drawings are omitted or simplified in order to facilitate understanding, and in some drawings, the degree of modification is exaggerated.

Also, in the figure, the Roman letters I and II mean the left and right wheels of the vehicle, respectively, and are used to help understand directions.

FIG. 1 illustrates a self-propelled vehicle (hereinafter referred to as a "vehicle") employing a suspension structure according to an embodiment of the present invention.

A sash 20 is coupled to a lower portion of the structure 10 forming the external shape of the vehicle and four drive wheel assemblies are coupled to the chassis 20. In the illustrated embodiment, the suspension structure of the present invention is applied to the two rear drive wheel assemblies 30L and 30R, and the two front drive wheel assemblies 30 are directly fixed to the chassis 20 . In another embodiment, a freely rotatable wheel may be provided in place of the front two-drive wheel assembly.

2, the drive wheel assemblies 30L and 30R are provided with a wheel 331 and include a drive motor unit 332 for rotating the wheel 331 in the forward direction or the reverse direction, And a motor unit 321.

The steering plate 32 is rotatably mounted on the lower surface of the base plate 31 and the steering plate 32 is rotatable on the horizontal plane with respect to the base plate 31 by the operation of the steering motor unit 321. A configuration in which the steering plate 32 is connected to rotate with respect to the base plate 31 and a configuration in which the steering plate 32 is rotated can adopt an already known configuration.

A mounting bracket 33, to which a wheel 331 and a driving motor unit 332 are coupled, is fixed to a lower portion of the steering plate 32.

Accordingly, the drive wheel assemblies 30L and 30R can rotate the wheel 331 in the forward direction or the reverse direction, and can control the traveling direction of the wheel 331. These drive wheel assemblies 30L and 30R may adopt one of a variety of products already in commerce.

The drive wheel assemblies 30L and 30R located on the left and right rear sides of the chassis 20 are coupled to the chassis 20 through the vertical guide members 40. [

In the illustrated embodiment, the vertical guide member 40 is a plurality of LM guides. Specifically, the housing 41 of the LM Guide is fixed to the chassis 20, and the rod 42 extending freely from the housing 41 is fixed to the base plate 31 of the drive wheel assembly.

By installing multiple LM guides side by side on a single drive wheel assembly, the drive wheel assembly can be stably mounted in the chassis. The drive wheel assembly can be reliably constrained to only move up and down.

Although not shown, the vertical guide members can be modified by various mechanisms or devices that ensure free linear movement. Furthermore, a shock absorber or the like having a smaller elasticity than the load of the structure to be placed on the cradle or the like may be used together with a linear movement mechanism or the like.

A first cam member 60A and a second cam member 60B are coupled to both ends of the rotating shaft 50 in such a manner as to be rotatable about the axis of the rotating shaft 50 And is eccentrically fixed to the center. The first cam member 60A and the second cam member 60B rotate together with the rotary shaft 50 together with the rotary shaft 50. [

Here, the first cam member 60A and the second cam member 60B have the same cross-sectional shape, and eccentric directions with respect to the axis center of the rotary shaft 50 are opposite to each other.

Here, the eccentric direction means a direction vector from the center of the circular cam members 60A and 60B toward the center of the cross section of the rotary shaft 50. [ 2, when the first cam member 60A is eccentric from the center of the rotating shaft 50 (see arrow p1) and the second cam member 60B is eccentric from the center of the rotating shaft 50 Direction (see arrow p2), which are opposite to each other.

The first and second cam members 60A and 60B are fixed to the drive wheel assemblies 30L and 30R, respectively, by a shaft holder 52 mounted on the chassis 20, As shown in Fig.

As a result, the left and right drive wheel assemblies 30L and 30R bear the load of the chassis 20 and the structure without elasticity. The front drive wheel assembly is secured directly to the bottom of the chassis, so that the chassis and structure are eventually supported by the drive wheel assembly without resiliency.

1 and 2, a support block 311 protrudes above the drive wheel assemblies 30L and 30R and a through hole 21 through which the support block 311 passes is formed in the chassis 20 Respectively.

The rotary shaft 50, the first cam member 60A and the second cam member 60B are provided on the upper portion of the chassis 20. [ The first cam member 60A and the second cam member 60B are provided so as to contact the upper end surfaces of the support blocks 311 of the drive wheel assemblies 30L and 30R exposed through the through holes 21. [

The arrangement of the components reduces the height of the ground surface of the vehicle, thereby reducing the center of gravity of the vehicle as much as possible, thereby improving the performance of the vehicle and ensuring a large mounting space.

On the other hand, in the embodiment shown in Figs. 1 to 5, the first cam member 60A and the second cam member 60B have a disk shape with a circular cross section.

The cam members 60A and 60B are mounted with the bearings 61 so that the outer circumferential surface portion 62 is free to rotate Lt; / RTI >

Accordingly, the cam member can be rotated more smoothly during the operation process described later, thereby improving operational reliability and reducing the possibility of wear due to friction with the support block.

3 to 6 relate to the use state of the suspension structure according to the present invention.

In FIGS. 5A, 5B and 6B, the suspension structure is viewed from the rear, and the left and right sides of the suspension structure are viewed from the left side of the left and right drive wheel assemblies, respectively.

Referring to FIGS. 4 and 5 schematically showing the drive wheel assemblies 30L and 30R and the cam members 60A and 60B, the left and right drive wheel assemblies 30L and 30R, which occur as the vehicle passes over the uneven floor of the factory, 30R, the rotation shaft 50 and the cam members 60A, 60B rotate.

The ascending or descending of either one of the drive wheel assemblies is interlocked with the descending or rising of the other drive wheel assemblies. The alternating ascending and descending operations of the left and right drive wheel assemblies are made by the cam shafts and the rotating shafts integrally rotating in the forward or reverse direction.

As a result, the two drive wheel assemblies evenly support the load on the vehicle, and are grounded to the ground with a height difference. At this time, the vehicle is kept horizontal.

Figures 4 (a), 4 (b) and 5 (a) show the left and right drive wheel assemblies lying on a flat floor and being substantially horizontal.

4A and 4B, the center 51 of the rotary shaft 50 is placed on a vertical line V passing through the center of the axis of the wheel 331 provided in the drive wheel assembly. On the other hand, the center 63 of each of the cam members 60A and 60B is spaced apart from the vertical line V by a horizontal distance d. However, the first cam member 60A of the left drive wheel assembly 30L shown in Fig. 4A is biased to the right in the drawing, and the right drive wheel assembly 30L shown in Fig. The second cam member 60B is biased to the left in the drawing, and the eccentric horizontal distance from the left and right drive wheel assemblies is equal to d but the eccentric directions are opposite to each other.

Figures 5 (b) and 6 (a) conceptually illustrate the operation of the suspension structure that occurs at the moment of entering the uneven floor. When the right drive wheel assembly 30R enters the bottom recessed state, the right drive wheel assembly 30R moves on its lowered floor to its own weight. From the perspective of the chassis, the right drive wheel assembly 30R is lowered from its original horizontal height.

At this time, the load of the vehicle is concentrated on the left drive wheel assembly 30L, which is indicated by a block arrow in the figure. Since the first cam member 60A is eccentrically fixed to the rotating shaft 50, the first cam member 60A rotates in the counterclockwise direction (see FIG. 6A).

As a result, as shown in Fig. 6B, the first cam member 60A is rotated counterclockwise by an angle A, the support block of the left drive wheel assembly 30L is supported at the new point, The second cam member 60B also rotates counterclockwise by an angle A to support the support block of the right drive wheel assembly 30R.

During this process, the ground level of the vehicle from the floor on the left side is reduced by 1/2 of the height difference between the left and right sides. With respect to the chassis with the different viewpoints, the left drive wheel assembly 30L rises and the right drive wheel assembly 30R descends.

As a result, both of the left and right drive wheel assemblies 30L and 30R are in full contact with the floor having a different height, and the loads of the vehicle are evenly supported by the left and right drive wheel assemblies through the respective cam members 60A and 60B. In addition, the vehicle including the rotary shaft 50 is maintained in a horizontal position despite the deviation of the floor.

5 (b) for easy understanding of the operating relationship of the suspension structure according to the present invention, it will be understood that the cam member and the operating block do not fall off and operate continuously during actual operation.

The operation of the rotating shaft and the cam members occurs when a difference in height occurs between the two drive wheel assemblies to which the suspension structure is applied, and also applies to a case where one of the drive wheel assemblies ascends higher than the other.

Fig. 7 shows the elliptical cam members 60C and 60D employed in the suspension structure according to the other embodiments. Other configurations, which are not shown, are the same as those of the above-described embodiment.

7 (a), the short axis portion of the cam member 60C contacts the support block 311 of the drive wheel assembly. Fig. 7 (b) shows another embodiment in which the long axis portion Is in contact with the support block 311 of the drive wheel assembly.

By adopting the elliptical cam members 60C and 60D, it is possible to make the rotating shaft more responsive or insensitive when one of the drive wheel assemblies ascends and descends.

Specifically, as shown in FIG. 7 (b), when the long axis portion of the elliptical cam member 60C is configured to support the drive wheel assembly, the height of both drive wheel assemblies It can react more sensitively to cars.

On the other hand, as shown in Fig. 7A, when the short axis portion of the elliptical cam member 60D is mounted on the drive wheel assembly, the sensitivity can be lowered compared with the circular cam member.

8 shows another example in which the suspension structure is applied. In Fig. 8, the arrow at the upper end indicates the forward traveling direction.

The drive wheel assemblies 301 to which the suspension structure is applied are arranged in a front-to-rear direction so that a suspension structure can be applied to front and rear wheels (see Figs. 8A and 8B).

Alternatively, the suspension structure may be applied to the front left and right drive wheel assemblies 301, and may be selectively applied to left and right front wheels or right and left rear wheels (see (c) and (d) of FIG. 8).

9 to 10 relate to a non-elastic suspension structure of an automatic traveling vehicle according to another embodiment of the present invention.

The suspension structure of the illustrated embodiment includes a chassis 20 and a drive wheel assembly 30L and 30R and includes a vertical guide member 40 for movably restraining the drive wheel assembly 30L and 30R only in the vertical direction, And a rotating shaft 50 mounted on the rotating shaft 20. A pinion 80 provided at both ends of the rotary shaft 50 and a rack member 34 connected to the pinion 80 and coupled to the drive wheel assemblies 30L and 30R. These constituent elements include the technical features of the above-described embodiments in a range not contradicting to the following description.

The rotary shaft 50, which is rotatably mounted on the upper portion of the chassis 20, is free to rotate. A pinion 80 is coupled to both ends of the rotating shaft 50, and the pinion 80 rotates integrally with the rotating shaft 50.

The rack member 34 is a structure vertically erected on the upper part of the drive wheel assemblies 30L and 30R, and a rack is provided on one side of the structure to engage with the pinion.

The coupling directions of the rack members connected to the left and right pinions 80 on the left and right sides of the rotating shaft are opposite to each other in the right and left pinions 80. In other words, the direction in which the rack members 34 and the respective pinions 80 are coupled is symmetrical with respect to the axis center of the rotary shaft 50.

Specifically, the rack member 34 of the left drive wheel assembly 30L is connected to the front side of the left pinion 80 and the rack member 34 of the right drive wheel assembly 30R is connected to the right pinion 80. [ As shown in Fig.

Since the coupling directions of the left and right pinions 80 and the rack members 34 are opposite to each other, when one of the drive wheel assemblies 30L rises and the pinions and the rotational shaft rotate, the other drive wheel assembly 30R And is lowered together with the rack member (34) by the rotation of the pinion (80).

That is, the pair of drive wheel assemblies 30L and 30R connected by the rotary shaft 50 and the both pinions 80, as in the above-described embodiment, do.

The synchronized upward and downward movement of the left and right drive wheel assemblies 30L and 30R is the same as the suspension structure of the embodiment described above. When the two drive wheel assemblies enter a floor which is not flat, the operation as shown in FIGS. .

Elastic elements are excluded when the drive wheel assemblies 30L and 30R bear the load including the chassis through the connection of the pinion 80 and the rack member 34. [ That is, a non-elastic suspension structure.

The gear engagement of the pinion 80 and the rack member 34 causes the rotation of the pinion due to the rise or fall of any one of the drive wheel assemblies and the descent or rise of the other drive wheel assembly due to the rotation of the pinion without slipping . Thereby, there is an advantage that the operation of the suspension is made very accurately.

The suspension structure according to an embodiment of the present invention allows the wheels of the drive wheel assembly to come into contact with the floor completely while the vehicle passes over an uneven floor. Also, the height of the drive wheel assembly is changed and the vehicle is leveled during the contact with the uneven floor. Such a drive wheel assembly does not elastically move upward and downward but has an inelastic structure by a cam member, and does not change the height of the vehicle at all during the process of getting on and off the vehicle. As a result, it is possible to reduce the intervention of complicated control elements for tracking and correcting the positional relation according to the height change of the vehicle during the up / down operation, thereby greatly improving the control efficiency of the automation system.

10: Structure
20: Chassis 21: Through hole
30, 30L, 30R. 301: Drive wheel assembly
31: base plate 311: support block
32: Steering plate 321: Steering motor section
33: mounting bracket 331: wheel 332:
34: Lack member
40: vertical guide member 41: housing 42: rod
50: rotation shaft 51: center 52: shaft holder
60A: first cam member 60B: second cam member 60C, 60D: cam member
61: Bearing 62: Outer surface 63: Center
80: Pinion
p1, p2: arrow V: vertical line

Claims (6)

A suspension structure for connecting a chassis of a lower portion of an autonomous vehicle to a drive wheel assembly,
A pair of the drive wheel assemblies being vertically movable relative to the chassis,
A rotation shaft to which the shaft is rotatably fixed to the chassis,
A first cam member and a second cam member eccentrically coupled to the rotation shaft and rotated together with the rotation shaft, the first cam member and the second cam member having an outer circumferential surface in contact with an upper end surface of each of the drive wheel assemblies,
The direction in which the first cam member is eccentric from the center of the rotation shaft and the direction in which the second cam member is eccentric from the center of the rotation shaft are mutually opposite directions
A non-elastic suspension structure of an automotive vehicle. The method of claim 1,
Wherein the first cam member and the second cam member are in the form of a disk having a circular cross section,
And an outer circumferential surface portion contacting the upper end of the drive wheel assembly is supported by a bearing
A non-elastic suspension structure of an automotive vehicle. The method of claim 1,
Wherein the first cam member and the second cam member are disc-shaped having an elliptical cross section
A non-elastic suspension structure of an automotive vehicle. The method of claim 1,
A support block protrudes above the drive wheel assembly,
Wherein a passage hole through which the support block passes is formed in the chassis,
Wherein the rotation shaft, the first cam member, and the second cam member are mounted on the upper portion of the chassis, and support the upper end surface of the support block protruding above the upper surface of the chassis
A non-elastic suspension structure of an automotive vehicle. The method of claim 1,
The vertical guide member
Wherein the housing is fixed to the chassis and the rod extending freely in the housing is a plurality of LM guides fixed to the drive wheel assembly
A non-elastic suspension structure of an automotive vehicle.
A suspension structure for connecting a chassis of a lower portion of an autonomous vehicle to a drive wheel assembly,
A pair of the drive wheel assemblies being vertically movable relative to the chassis,
A rotation shaft to which the shaft is rotatably fixed to the chassis,
A pinion coupled to both ends of the rotary shaft and rotatable integrally with the rotary shaft,
And a rack member coupled to each of the drive wheel assemblies and integrally moving up and down with the drive wheel assembly and gear-engaged with the pinion,
Wherein a direction in which the rack member of each of the drive wheel assemblies is coupled with each of the pinions is symmetrical with respect to an axis center of the rotational shaft, and both the up and down movements of the drive wheel assemblies are opposed to each other
A non-elastic suspension structure of an automotive vehicle.

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