KR20220156384A - Wheel drive apparatus of automated guided vehicle - Google Patents

Abstract

Disclosed is a wheel driving apparatus for an unmanned transport vehicle. The wheel driving apparatus for an unmanned transport vehicle includes: a lower driving frame (1) equipped with a steering and driving system and transmitting power; an upper bogie frame (2) loading transported goods and coupled on an upper side of the lower driving frame (1); an auxiliary wheel (21) installed integrally on a lower side of the upper bogie frame (2); a driving wheel (11) installed inside the lower driving frame (1) to receive power and perform steering and driving; a lifting block (22) forming a lifting frame (221) forming an upper plate unit (224), a lower plate unit (223), a side wall unit (227), and a support wall unit (225), and a support bracket (226) such that the auxiliary wheel (21) of the upper bogie frame (2) is lifted in contact with a floor; a rotary unit (23) forming a rotary shaft (231), a lifting bracket (232) and a lifting plate unit (233); and a guide block (25) in which a guide frame (251) provided with an upper plate unit (253) and a guide shaft (252) are installed side by side. Therefore, the present invention is capable of mitigating an issue in which an unmanned transport vehicle is driven on a slope in an unexpected direction when only one wheel is operated.

Description

Wheel driving device of an unmanned guided vehicle {WHEEL DRIVE APPARATUS OF AUTOMATED GUIDED VEHICLE}

The present invention is an unmanned transport vehicle (unmanned transport vehicle, hereinafter referred to as an unmanned transport vehicle) having steering and driving wheels (hereinafter referred to as driving wheels) and a plurality of auxiliary wheels (hereinafter referred to as auxiliary wheels). While driving, even if the floor is depressed (hereinafter referred to as a depression), protruded (hereinafter referred to as a protrusion), or inclined (hereinafter referred to as an inclined surface), the driving does not stop, and the driverless guided vehicle is capable of traveling in all directions. It is about the wheel drive system.

In general, various bogies for transporting materials, semi-finished products, or parts are used in industrial sites such as automobile assembly lines or parts processing lines. Recently, automatic guided vehicles (AGVs) have been adopted and used in places such as distribution centers that handle large-scale products. Guidelines or laser scanners installed on the ground It moves by recognizing the path with a sensor, and it is a device that moves cargo such as products or parts to another place without the operator directly driving.

On the other hand, such an unmanned guided vehicle sometimes stops driving on a bottom surface that is depressed (depression part), protruded (protrusion part), or inclined while driving with cargo. That is, if the driving wheel of the driverless guided vehicle is floating between the front auxiliary wheel or the rear auxiliary wheel in various situations on the floor while the driverless guided vehicle is running depending on the road surface condition of the floor, the driving is stopped and the unloading position is not reached. There are things that happen. It is that the front and rear auxiliary wheels touch the floor, but the drive wheel installed in the middle of the lower drive frame floats on the ground, so that the unmanned transport vehicle is in a stopped state where it cannot run, and as described above, automation There is a disruption in the supply of parts for one facility.

General tricycle drive and differential drive type unmanned transport vehicles cannot move immediately to the left or right in the direction of travel, but can move through a path with a large turning radius, so the movement passage is narrow and multiple equipment It was to the extent that it was impossible to freely change directions in various directions in a complexly installed place.

The omni-rectional carriage can move immediately forward, backward, left and right in all directions without forming a wide turning radius. In other words, by adding a device to the drive wheel, it is possible to move in all directions by combining the rotation direction of the drive wheel and the steering angle, but the additional configuration is complicated, and the drive wheel does not It stays afloat, causing the automated guided vehicle to stop or move in an undesired direction, causing it to deviate from its course. Therefore, the driving stability of the unmanned guided vehicle is lowered and the accuracy of the driving direction is lowered, which adversely affects the driving of the bogie and lowers the operation efficiency.

On the other hand, looking at the condition of the floor in the driving environment of the unmanned guided vehicle, it is impossible to make the entire floor perfectly flat in terms of construction. In the actual floor environment where the unmanned guided vehicle runs, there are various complexities such as gentle protrusions, depressions, and slopes on the floor, which causes the driving wheels of the unmanned guided vehicle to float off the ground depending on the condition of the floor. there is When the drive wheel is floating, the driving of the automated guided vehicle stops, and since only one drive wheel moves, the automated guided vehicle may travel in an undesirable direction.

In addition, in the case of Patent No. 10-2140480, which was previously filed by the present inventor, a truck frame and a drive frame are constituted, and a pivoting shaft portion pivotally coupled to an axis point of the truck frame and the drive frame, and a drive frame on the outside of the opposite sides of the truck frame. In the positioning state, the bogie frame forms a first connecting arm having a pipe hole equipped with a bearing and a bushing, and the drive frame forms a second connecting arm, and the second connecting arm also has a pipe hole equipped with a bearing and a bushing. Disclosed is a wheel travel device for an unmanned guided vehicle consisting of a connecting part in which a slip rod is vertically installed so that the first and second connecting arms move up and down in the pipe at an interval (a). This unmanned transport vehicle had a disadvantage that it was impossible to drive in all directions. Therefore, there is a need for a driving structure method of an unmanned guided vehicle that can narrow the driving radius with a simpler structure and assembly and can immediately run in a meandering direction. Therefore, a driving structure method of an unmanned guided vehicle that can narrow the range of turning radius with a simpler structure and assembly and can immediately drive in an inclined direction was required.

In addition, it is ideal to have all the wheels of the known unmanned guided vehicle touch the floor, but in reality, the wheels touch or float on the floor alternately depending on the state of the floor.

The role of the bogie frame with auxiliary wheels (hereinafter referred to as the upper bogie frame) is to drive the drive frame with steering and driving wheels (hereinafter referred to as the lower drive frame) while transferring the load of the transported cargo and the truck to the floor. It moves by determining the direction of movement according to the direction. The role of the auxiliary wheels installed on the upper bogie frame is to move passively while matching the direction according to the running direction of the driving wheels installed on the lower driving frame while transferring the load of the transported cargo and the truck to the floor. At this time, even if some of the auxiliary wheels temporarily float on the floor, they do not significantly affect driving. This is because the driving wheels having steering and driving functions transmit the desired direction and driving force to the floor to move the unmanned guided vehicle.

In addition, not only forward and backward movement, but also left and right movement and meandering (when moving between the right angle ranges in each direction, not the right angle range of front, rear, left, and right, it is hereinafter referred to as meandering) Even for movement, etc., the driving wheels must be in perfect contact with the floor surface to enable accurate driving of the driving wheels.

Therefore, it is required to prevent the driving wheels from floating on the floor even when the moving unmanned guided vehicle encounters a depression, a protrusion, or an inclined surface of the floor.

1. Republic of Korea Patent Registration No. 10-0849413 (published on July 24, 2008) 2. Republic of Korea Patent Registration No. 10-2140480 (2020.08.03 notice)

1.JP 2014-218183 A (published on November 20, 2014 2. Republic of Korea Patent Publication No. 10-2020- 0025102 (published on March 10, 2020

In order to improve the above disadvantages and problems, the wheel driving device for an unmanned guided vehicle of the present invention does not stop driving even when an unmanned guided vehicle composed of at least one driving wheel and auxiliary wheels travels on a depression, protrusion, or slope of the floor while driving. Its purpose is to enable omnidirectional driving without interruption.

According to the present invention, the wheel driving device of an unmanned guided vehicle prevents the driving wheel from floating off the floor even if the driving wheel having steering and driving functions in a moving unmanned guided vehicle encounters an unexpected situation on the floor, that is, a depression, a protrusion, or an inclined surface during movement. Its purpose is also to prevent it.

In the wheel driving device of the present invention for achieving the above object, an object of the present invention is to achieve a stable landing structure using auxiliary wheels so that the driving wheels are in close contact with the floor.

A wheel travel device for an unmanned guided vehicle according to an embodiment of the present invention for achieving the above object.

A lower driving frame for mounting a steering and driving system and transmitting power;

An upper truck frame loaded with transported goods and coupled from above the lower driving frame;

Auxiliary wheels integrally installed on the lower side of the upper bogie frame;

a driving wheel installed inside the lower driving frame to receive power and steer and drive; and

an elevating unit that elevates the auxiliary wheel of the upper bogie frame to contact the floor;

including,

The lifting unit,

An elevating frame composed of an upper plate coupled to the upper bogie frame, a lower plate having a support bracket, a side wall connecting the upper and lower plates, and a support wall having a shaft hole formed between the side walls, Elevating blocks formed with support brackets for rotatably supporting the auxiliary wheels on the lower part of the frame;

a rotational unit comprising a rotational axis rotatably installed in the shaft hole of the elevation block, an elevation plate portion to which the rotation axis is fixed, and an elevation bracket installed on the other side of the elevation plate portion; and

An unmanned guide block including a guide frame having four sides forming a top plate fixed to the lower drive frame and having guide shafts slipped into the lift holes of the lift brackets inside the guide frame. It is a wheel driving device of a transportation vehicle.

The rotation unit of the wheel traveling device of the unmanned guided vehicle according to an embodiment of the present invention for achieving the above object,

A pivoting shaft is rotatably installed in the shaft hole of the lifting block and fixed with a fixing nut, and the other end of the pivoting shaft is fixed to the lifting plate on the opposite side with a shaft closing nut, enabling the lifting block to rotate. is a wheel travel device of

In order to achieve the above object, it is preferable that the elevating brackets of the wheel travel device of an automatic guided vehicle slip inside each elevating hole through which the guide shaft elevates and descends as a slip member.

In order to achieve the above object, it is preferable that any one pair of pivoting shafts of the two pairs of lifting units of the wheel traveling device of an unmanned guided vehicle according to an embodiment of the present invention have a feature that is eccentric between the lifting block and the guide block. .

In order to achieve the above object, it is preferable that the slip members of the wheel traveling device of an automatic guided vehicle according to an embodiment of the present invention are bushings.

According to a preferred embodiment of the present invention, the wheel traveling device of an unmanned guided vehicle does not stop driving and travels in all directions even when an unmanned guided vehicle composed of at least one driving wheel and auxiliary wheels travels on a depression, protrusion, or slope of the floor while driving. Get the effect of running.

According to a preferred embodiment of the present invention, the driving device for driving a wheel of an unmanned guided vehicle is driven even when a driving wheel having a steering and driving function in a moving unmanned guided vehicle encounters an unexpected situation on the floor, that is, a depression, a protrusion, or an inclined surface during movement. None of the wheels come off the floor and get the effect of being in close contact with the floor.

According to a preferred embodiment of the present invention, the wheel driving device of an unmanned guided vehicle conventionally stops or moves only one driving wheel in an undesirable direction when driving wheels meet an unexpected situation on the floor, that is, a depression, a protrusion, or an inclined surface while moving. driving is improved.

According to a preferred embodiment of the present invention, a wheel travel device of an unmanned guided vehicle includes a lower driving frame for mounting a steering and driving system and transmitting power so that the driving wheels are in close contact with the floor, and loading a cargo and moving the upper part of the lower driving frame. In addition to the upper bogie frame coupled in the upper bogie frame, the auxiliary wheel integrally installed below the upper bogie frame, and the driving wheel installed inside the lower driving frame to receive power and steering and driving, the auxiliary wheel of the upper bogie frame A stable landing structure is provided through the lifting unit installed to contact the floor.

1a and 1b are side schematic views and front schematic views according to an embodiment of a wheel travel device for an unmanned guided vehicle according to the present invention;
2 is a schematic perspective view of a partially omitted lower drive frame according to an embodiment of a wheel travel device of an unmanned guided vehicle according to the present invention;
3A is a front schematic view of an upper bogie frame of the wheel traveling device of an unmanned guided vehicle according to the present invention, and FIG. 3B is a front schematic view omitting a part of the lower driving frame of the wheel traveling device of an unmanned guided vehicle according to the present invention.
4 is an exploded perspective view of an enlarged elevation unit of a wheel travel device of an unmanned guided vehicle according to the present invention;
5 is an enlarged combined perspective view of the lifting unit of the wheel traveling device of the unmanned guided vehicle of the present invention;
6(a), (b), and (c) are schematic diagrams illustrating the operating state of the lifting unit and the guide unit of the wheel driving device of the unmanned guided vehicle according to the floor situation according to the present invention,
Figure 7 (a) (b) is a side view explaining the left and right rotation action of the lifting unit of the wheel travel device of the automatic guided vehicle of the present invention,
8 (a) (b) is a side view illustrating expansion and rotation when the rotation axis of the lifting unit of the wheel traveling device of the automatic guided vehicle according to the present invention is eccentric,
9 (a) to (h) are operational explanatory diagrams for explaining the operating state of the wheel traveling device of the present invention for each floor situation when moving forward and backward,
10 (a) to (f) are operational explanatory diagrams explaining the actions of the drive wheels and auxiliary wheels for each floor situation when the wheel traveling device of the unmanned guided vehicle of the present invention moves on a slope,
11(a) to (d) are front views illustrating the operation of the driving wheel and the auxiliary wheel according to the front movement situation of the wheel driving device of the automatic guided vehicle according to the present invention.

Hereinafter, a detailed configuration of a wheel travel device of an unmanned guided vehicle according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

Among the accompanying drawings, FIGS. 1a and 1b are a schematic side view and a front schematic view according to an embodiment of a wheel travel device for an unmanned guided vehicle according to an embodiment of the present invention, and FIG. 2 is partially omitted according to an embodiment of the wheel travel device for an unmanned guided vehicle A schematic perspective view of the lower driving frame of the present invention, Figure 3a is a front schematic view of the upper bogie frame extracted from the wheel traveling device of the automatic guided vehicle of the present invention, Figure 3b is a part of the lower driving frame of the wheel traveling device of the present invention Fig. 4 is an enlarged perspective view of the lifting unit of the wheel traveling device of the unmanned guided vehicle of the present invention, and Fig. 5 is an enlarged combined perspective view of the lifting unit of the wheel traveling device of the present invention. .

The wheel travel device of the present invention shown in FIGS. 1A and 1B in the drawings is divided into a lower driving frame 1 and an upper bogie frame 2.

The unmanned transport vehicle is composed of an upper bogie frame (2) for loading cargo and a lower driving frame (1) having a driving force as a driving wheel by mounting a steering and driving system, steering and driving system of the lower driving frame (1) Driving wheels 11 are provided at the front and rear of the bottom side of the lower driving frame 1 to move by receiving driving and steering power from, and between the lower driving frame 1 and the upper bogie frame 2, a lifting unit ( 20) is connected.

On the upper bogie frame 2 connected in this way, auxiliary wheels 21 rotatably installed on the elevating unit 20 are installed in front and rear, respectively, in left and right directions. The auxiliary wheel 21 performs a function of assisting the driving of the driving wheel 11 by stably landing on the floor as well as handling the loaded load when the driving wheel 11 is driven by the lower driving frame 1. do.

In addition, the lower driving frame 1 can be moved in all directions through an active weight balance, a control computer, etc., can be lifted in up and down directions, and is linked with a sensor device that detects the surrounding environment. Configurations and functions capable of actively coping with safety issues that occur during movement and loading and unloading processes may be included. That is, the control computer and sensor unit detects the front black floor situation, and as an electrical signal, it is accompanied by control means capable of controlling steering such as continuing driving, driving stop, straight driving, left and right turn, and inclined movement, etc. It may include a power supply means including. Detailed descriptions of various sensing means and signaling means for this steering and drive system will be omitted.

Among the drawings, FIG. 2 shows a state in which the upper truck frame 2 and the lower driving frame 1 are coupled, and the upper loading space is omitted. As shown in the drawing of FIG. 3A, the lift installed on the upper truck frame 2 The block 22 and the auxiliary wheel 21 connected thereto are shown, and FIG. 3B shows the guide block 25 and the driving wheel 11 connected to the lower drive frame 1.

The first and second lifting blocks 22 and 25 may be combined and installed as shown in FIG. 2. In this case, the rotation shaft 231 of the rotation unit 23 is between the elevation block 22 and the guide block 25. ) is rotatably connected, and at the same time, the guide shaft 252 of the guide block 25 is vertically assembled and installed in the lifting bracket 232 of the rotation unit 23 so as to be able to move up and down.

The lower driving frame 1 coupled through the elevating unit 20 in this way mounts a steering and driving system and transmits power to the driving wheels. Driving wheels 11 can be installed inside the lower driving frame 1 to steer and drive, and the upper truck frame 2 loads transported goods and is coupled above the upper driving frame. The auxiliary wheel 21 of the lifting block 22 installed in the upper bogie frame 2 is integrally installed on the lower side of the upper bogie frame 2.

The lifting unit 20 shown in FIGS. 4 and 5 of the accompanying drawings can be largely divided into a lifting block 22, a rotation unit 23, and a guide block 25.

The lifting block 22 forms an upper plate portion 224 coupled to the upper bogie frame 2, and a four-sided lifting frame 221 forming a support bracket 226 for supporting the auxiliary wheel 21 on the lower plate portion 223. ) can be formed. One side of the elevating frame 221 forms an opening, and the other side forms a support wall 225 to be blocked.

A shaft hole 222 is formed in the support wall portion 225 so that a pivoting shaft 231 to be described later is rotatably installed and fastened as a fixing nut 24 .

A support bracket 226 is installed on the lower plate 223 of the elevating frame 221 so that the auxiliary wheel 21 is rotatably installed.

The rotation unit 23 includes a rotation axis 231 installed in the shaft hole 222 of the elevation block 22, an elevation plate portion 233 on which the rotation axis 231 is installed, and one side of the elevation plate portion 233. The pivoting shaft 231 is rotatably installed in the shaft hole 222 of the lifting block 22, consisting of at least one lifting bracket 232 installed in the lifting block 22.

The guide block 25 forms a guide frame 251 on four sides forming an upper plate portion 253 fixed to the lower drive frame 1, and lifts the bracket 232 vertically from the inside of the guide frame 251. Guide shafts 252 that are inserted in the axial direction so as to slip on and move up and down can be arranged side by side.

In the rotation unit 23, a rotation shaft 231 is rotatably installed in the shaft hole 222 of the lifting block 22, and one end thereof is fixed with a fixing nut 24, and the other end is the rotation unit 23 It is fixed to the other side of the lifting plate part 233 with a shaft closing nut 234, and the free rotation of the lifting block 22 can be installed. Figure 5 of the accompanying drawings shows such a coupled state after assembly.

In addition, in the rotation unit 23, the rotation shaft 231 is rotatably fixed to the shaft hole 222 of the lifting block 22 with a fixing nut 24, and the other end of the rotation shaft 231 is the rotation unit on the opposite side. It can be fixed with a nut member 234 for fixing the axis by penetrating to be fixed to (23).

On the other hand, the pivot axis 231 is an eccentric axis, and its axial center may be different. The eccentric rotation shaft 231 is formed on any one pair of rotation shafts 231 of the two pairs of lift units 20, and the lift block 22 installed on the pair of lift units 20 and the guide A rotation axis 231 that is eccentric between the blocks 25 may be implemented.

As shown in FIG. Alternatively, it can be extended to 10,6 °. That is, the rotation shaft 231 of the front elevation unit 20 is used as a reference shaft for fixing the lower driving frame 1 and the upper bogie frame 2, and the rotation shaft 231 of the rear elevation unit 20 is the eccentric rotation shaft ( 231), the guide shaft 252 is lifted and moved with a slight deviation between the center rotation axis 231 of the elevation block 22 and the center rotation axis 231 of the guide block 25 according to the state of the floor surface. By absorbing the ball 235 as a slip member, the guide shaft 252 smoothly slips in the elevating bracket 232 so that the pivoting shaft 231 can operate eccentrically.

In addition, the elevating bracket 232 may slip by inserting the slip member 236 into the elevating hole 235 in which the guide shaft 252 is vertically contracted. A bushing may be applied to the slip member 236. Therefore, the guide shaft 252 can act as a flexible elevation in the elevation hole 235 . Therefore, the auxiliary wheel 21 can descend and contact the floor as soon as it is lifted from the floor, so that the contact of the driving wheel 11 integrally installed in the lower drive frame 1 is affected to prevent it from floating will be.

In the wheel driving device of an unmanned guided vehicle according to an embodiment of the present invention, it is ideal that all wheels touch the floor. In fact, depending on the condition of the floor surface, the wheels alternately touch or float, and the auxiliary wheels move passively, matching the direction of the wheels according to the running direction of the drive wheels while transmitting the load of the transported cargo and the truck to the floor surface. Even if some of the auxiliary wheels temporarily float on the floor, they do not significantly affect driving. On the other hand, since the driving wheels must be driven by receiving power while performing the steering function, they must be in perfect contact with the floor surface to be steered and driven in the desired direction. This traveling operation is described in detail in the drawings shown in FIGS. 9 and 10 . In addition, the movement of the left and right sides or the direction of meandering movement within the perpendicular range of the front and side surfaces is explained by the bar shown in FIG. 9, and the driving wheel 11 must make perfect contact with the floor surface It is possible, and this allows the wheel travel device of the present invention to function.

The driving action according to the assembly configuration of the wheel traveling device of the present invention described above will be described through the accompanying drawings.

6 (a), (b), (c) of the accompanying drawings are schematic diagrams explaining the operating state of the lifting unit and the guide unit of the wheel driving device of the automatic guided vehicle according to the floor situation of the present invention, and FIG. 7 ( A) (b) is a side view illustrating the left and right rotation of the lifting unit of the wheel traveling device of the automatic guided vehicle according to the present invention, and (a) (b) of FIG. 8 is the wheel traveling device of the present invention. It is a side view explaining expansion rotation when the rotation axis of the lifting unit is eccentric. As shown in FIGS. 6 and 7, the wheel travel device of the automatic guided vehicle according to the present invention includes an integral lift bracket 232 along the guide shaft 252 slidably installed on each lift bracket 232 of the rotation unit 23. The whole of the rotation unit 23 and the lifting block 22 are raised and lowered according to the height of the floor.

That is, in (a) of FIG. 6, the auxiliary wheel 21 is located at the protruding portion and the lifting block 22 is raised. 6 (b) is a state in which the auxiliary wheel 21 is located on the same floor as the drive wheel 11, and in (c) of FIG. 6, the auxiliary wheel 21 is located in a puddle so that the lifting block 22 is it descended

In addition, in (a) of FIG. 7, the pivot shaft 231 is connected between the lifting block 22 and the guide block 25, and the upper bogie frame 2 is inclined in the direction of the arrow (left direction) to assist It shows a state where the wheel 21 is located on an inclined surface that is lowered in the direction of the arrow.

In (b) of FIG. 7, the pivot shaft 231 is connected between the lifting block 22 and the guide block 25, and the upper bogie frame 2 is inclined in the direction of the arrow (right direction), and the auxiliary wheel ( 21) indicates a state located on a slope that is lowered in the direction of the arrow.

That is, (a) and (b) of FIGS. 7 are not shown in FIGS. 9 and 10, but show how the rotation shaft 231 rotates when the front and rear lift units 20 are in different positions. Since it is shown, as described above, (a) of FIG. 7 is a case in which one of the front and rear lifting units 20 performs a lifting operation, and the driving wheel 11 connected to the lower driving frame 1 is horizontal, and the auxiliary wheel 21 is in the direction of the arrow, although the lifting block 22 of the auxiliary wheel 21 is inclined downward, the upper bogie frame 2 or the lower driving frame 1 is of any height Without forming a difference, the guide shaft 252 of the lifting unit 20 performs a lifting operation on the lifting bracket 232 of the pivot block 23, so that it can travel on an inclined floor without a difference in height. will be.

Conversely, (b) of FIG. 7 is a case in which the other one of the front and rear lifting units 20 performs a lifting operation, and the driving wheel 11 connected to the lower driving frame 1 is horizontal and auxiliary. In the wheel 21, although the lifting block 22 of the auxiliary wheel 21 is inclined downward in the direction of the arrow, the upper bogie frame 2 or the lower drive frame 1 forms a difference in height As the guide shaft 252 of the lift unit 20 moves up and down in the lift bracket 232 of the pivot block 23 without a difference in height, it is possible to travel on an inclined floor surface without a difference in height.

That is, the guide shaft 252 that slips up and down and moves up and down has no problem when the height of all the auxiliary wheels 21 and the height of contact with all the driving wheels are consistent with the floor in the horizontal direction, but the floor is tilted up and down. If present, it forms an angular contact height. The upper bogie frame 2 and the lower drive frame 1 having the guide block 25 slide the lifting block 22, which is raised and lowered in correspondence with each other, up and down so that it can rotate at two points, forward and backward. A rotating shaft 231 is formed at the center of the lifting plate 221, and the upper bogie frame 2 and the lower driving frame ( The unmanned guided vehicle combined with 1) can be stably driven without being affected by the special floor inclination angle.

Extended rotation when the rotating shaft of the lifting unit of the wheel traveling device of the automatic guided vehicle according to the present invention shown in (a) and (b) of FIG. 8 is eccentric will be described.

That is, the rotation range of the rotation shaft 231 having an eccentricity is, for example, the rotation range of the lifting block 22 of the rotation unit 23 as shown in (a) (b) of FIG. 8, 21.2°. or 10,6 °. That is, the rotation shaft 231 of the front elevation unit 20 is used as a reference shaft for fixing the lower driving frame 1 and the upper bogie frame 2, and the rotation shaft 231 of the rear elevation unit 20 is the eccentric rotation shaft ( 231), the guide shaft 252 is lifted and moved with a slight deviation between the center rotation axis 231 of the elevation block 22 and the center rotation axis 231 of the guide block 25 according to the state of the floor surface. By absorbing the ball 235 as a slip member, the guide shaft 252 smoothly slips in the elevating bracket 232 so that the pivoting shaft 231 can operate eccentrically.

A specific operation example for each situation shown in FIG. 6 follows the description of the drawings below.

9 (a) to (h) of the accompanying drawings are explanatory diagrams illustrating the side conditions of the wheel traveling device of the unmanned guided vehicle according to the present invention when it moves forward and backward.

9(a) shows that the front and rear auxiliary wheels 21 and the drive wheels 11 of the upper bogie frame 2 are located on an upward slope in the front and rear directions at the same time, but the center is located on a curved surface with a depression represents,

9(b) shows a state in which the front and rear auxiliary wheels 21 and the driving wheels 11 of the upper bogie frame 2 form a protruding surface in the middle and are located on a downward slope in the front and rear directions,

9(c) shows a state in which the driving wheels 11 of the lower driving frame 1 contact the protruding surface, but the front and rear auxiliary wheels 21 are located on a flat surface,

9(d) shows a state in which the driving wheel 11 of the lower driving frame 1 is located in a hollowed puddle, but the front and rear auxiliary wheels 21 are located on a flat surface,

9(e) shows a state in which the driving wheel 11 of the lower driving frame 1 is located on a flat surface, but the front and rear auxiliary wheels 21 are located on the protruding surface,

9(f) shows a state in which the driving wheel 11 of the lower driving frame 1 is located on a flat surface, but the front and rear auxiliary wheels 21 are located on the protruding surface,

9(g) shows a state in which the driving wheel 11 of the lower driving frame 1 is located on the inclined surface and one of the auxiliary wheels 21 is located on the protruding surface,

9(h) shows a state in which one of the driving wheels 11 of the lower driving frame 1 contacts the protruding surface, but the front and rear auxiliary wheels 21 are located on a flat surface.

10(a) to 10(f) are operational explanatory diagrams explaining the operation of the driving wheel and the auxiliary wheel for each floor situation during the lateral movement of the wheel traveling device of the unmanned guided vehicle according to the present invention,

10(a) shows the side driving state of the driving wheel 11 and the auxiliary wheel 21 in a state inclined to the left on the drawing,

10(b) shows the driving state of the auxiliary wheel 21 in a state where the driving wheel 11 is located on a flat surface at the same time that the auxiliary wheel 21 goes over the protrusion surface,

10(c) shows the side driving state of the drive wheel 11 and the auxiliary wheel 21 in a state inclined to the left on the drawing,

10(d) shows a side driving state in a state where the driving wheel 11 goes over the protrusion surface and the auxiliary wheel 21 is located on the flat surface,

10(e) shows a driving state in which one of the auxiliary wheels 21 goes over a puddle and the other auxiliary wheel 21 and the driving wheel 11 are located on a flat surface,

10(f) shows a driving state in which one of the auxiliary wheels 21 crosses the protrusion surface and the other auxiliary wheel 21 and the driving wheel 11 are located on a flat surface.

11(a) to (d) are front views illustrating the operation of the driving wheel and the auxiliary wheel according to the front movement situation of the wheel driving device of the automatic guided vehicle according to the present invention.

11(a) shows a driving state in a state where the driving wheel 11 goes over the protrusion surface and the auxiliary wheels 21 are located on a flat surface,

10(b) shows a driving state in a state in which the auxiliary wheels 21 are located on a flat surface in a state in which the driving wheel 11 is located in a place such as a hollow puddle,

11(c) shows a driving state in a state in which the auxiliary wheels 21 are located on a flat surface in a state where the auxiliary wheels 21 go beyond the protrusion surface,

11(d) shows a driving state in a state in which the driving wheels 11 are located on a flat surface in a state where the auxiliary wheels 21 are located in a place such as a hollowed puddle.

Through the situational operation of the drawings of FIGS. 9 to 11, the present invention prevents any one of the two driving wheels from floating off the floor even when the omnidirectional unmanned guided vehicle encounters depressions, protrusions, and upper and lower slopes on the floor. It is to provide a structure, and even if it travels on a depression, protrusion, or slope on the floor while driving, it does not stop and travels in all directions, and a driving wheel with steering and driving functions in a moving unmanned guided vehicle Even if it encounters an unexpected situation on the floor during movement, that is, a depression, a protrusion, or an inclined surface, none of the driving wheels will float off the floor, and driving in an unwanted direction by moving only one driving wheel is improved. While driving, the driving wheel is in close contact with the floor.

In particular, the wheel travel device of the unmanned guided vehicle of the present invention is equipped with a steering and driving system so that the driving wheels are in close contact with the floor and transmits power, and a lower driving frame for loading and coupling from above the lower driving frame. The auxiliary wheel of the upper bogie frame (2) in addition to the upper bogie frame, the auxiliary wheel integrally installed below the upper bogie frame, and the driving wheels installed inside the lower drive frame to receive power and steer and drive. It is to provide a stable landing structure through the lifting unit 20 configured to contact the floor (21).

In addition, the rear rotation axis is made of eccentricity, and the position deviation of the rear side of the upper and lower frames is compensated through the eccentric angle. That is, the driving force of the driving wheels of the lower frame in the front, rear, left and right directions is transmitted to the upper frame through the rotation shaft. Through such a means, the omnidirectional unmanned guided vehicle can drive stably without the driving wheels floating on various types of floor surfaces.

As described above, the preferred embodiments of the present invention have been described with reference to the drawings, but those skilled in the art can make various modifications to the present invention within the scope not departing from the spirit and scope of the present invention described in the claims below. may be modified or changed.

1: lower driving frame, 2: upper bogie frame, 11: driving wheel, 21: auxiliary wheel,
20: lifting unit, 22: lifting block, 221: lifting frame, 222: shaft, 223: lower plate,
224: top plate, 225: support wall, 226: support bracket, 23: rotation unit, 231: rotation axis,
232: lifting bracket, 233: lifting plate part, 234: shaft fixing nut member, 235: lifting ball,
236: slip member, 24: fixing nut, 25: guide block, 251: guide frame, 252: guide shaft,

Claims (5)

In an unmanned transport vehicle,
A lower driving frame for mounting a steering and driving system and transmitting power;
An upper truck frame loaded with transported goods and coupled from above the lower driving frame;
Auxiliary wheels integrally installed on the lower side of the upper bogie frame;
a driving wheel installed inside the lower driving frame to receive power and steer and drive; and
an elevating unit that elevates the auxiliary wheel of the upper bogie frame to contact the floor;
including,
The lifting unit,
An elevating frame composed of an upper plate coupled to the upper bogie frame, a lower plate having a support bracket, a side wall connecting the upper and lower plates, and a support wall having a shaft hole formed between the side walls, Elevating blocks formed with support brackets for rotatably supporting the auxiliary wheels on the lower part of the frame;
a rotational unit comprising a rotational axis rotatably installed in the shaft hole of the elevation block, an elevation plate portion to which the rotation axis is fixed, and an elevation bracket installed on the other side of the elevation plate portion; and
guide blocks forming four side guide frames that form an upper plate portion fixed to the lower driving frame, and having guide shafts slipped into the lift holes of the lift brackets inside the guide frames;
A wheel travel device for an unmanned guided vehicle comprising a. The method of claim 1, wherein the rotation unit,
The pivoting shaft is rotatably installed in the shaft hole of the lifting block and fixed with a fixing nut, and the other end of the pivoting shaft is fixed with a shaft closing nut to the lifting plate on the opposite side to enable rotation of the lifting block. A wheel driving device of an unmanned guided vehicle. The wheel travel device of claim 1, wherein the lift brackets slip as slip members inside each lift hole through which the guide shaft moves up and down. The wheel traveling device of claim 1, wherein any one pair of pivoting shafts of the two pairs of lifting units are eccentric between the lifting block and the guide block. The wheel traveling device of claim 3, wherein the slip members are bushings.

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