JPS6397424A - Moving bogie - Google Patents

Abstract

PURPOSE:To prevent the generation of the vibration of a body by separating driving wheels from the ground at the time of changing directions. CONSTITUTION:When the traveling direction of a bogie 10 is changed, first, free casters 11-14 are moved to the lower part of the bogie 10 by means of an up/down moving motor 45. And, the height of the ground contacting face of the free casters 11-14 is made lower than that of driving wheels 15, 16. Then, the bogie 10 is supported only by the free casters 11-14 and the driving wheels 15, 16 are kept off the ground.

Description

[Detailed description of the invention] (b) Industrial application field The present invention relates to a mobile cart that can run in any direction.

(b) Conventional technology In general, machines that can move in any direction, such as self-propelled robots and unmanned vehicles, have a main body that consists of a pair of drive wheels that are driven independently on the left and right sides, and a plurality of swivel casters, etc. It is mounted on a bogie that is supported by driving wheels and runs.

As such a trolley, for example, JP-A-60-20'
There is one disclosed in Publication No. 1132Q (omnidirectional movable trolley).

This conventional device, as shown in FIGS. 4(a) to 4(d),
Drive wheels 2 and 3 are arranged at the right front and left rear of the bogie 1, respectively, and driven shafts 4.5 are arranged at the left front and right rear, respectively.
, 5 are attached to the truck 1 via steering shafts 6, 7, 8.9, respectively.

Therefore, when changing the running direction by 90 degrees.

By the steering shafts 6, 7, 8.9, Fig. 4(a)
The driving wheels 2 and 3 are changed from the state shown in FIG.
And the direction of the driven shafts 4 and 5 is changed.

Also, when rotating one cart 1 on the spot,
), the axle directions of the driving wheels 2, 3 and driven shafts 4, 5 are aligned with the direction of the diagonal line of the truck 1 using the steering shafts 6, 7, 8.9, and in this state, the driving wheels 2.3 are driven. I'm letting you do it.

(c) Problems to be Solved by the Invention However, in such a conventional device, for example, FIG.
) to the state shown in (b) of the same figure.
, 8.9, when the driving wheels 2, 3 and the driven wheels 4, 5 are respectively rotated, the driving wheels 2, 3 move while being in contact with the ground and receiving frictional force. There was a risk of vibration occurring.

In addition, since four motors for the steering shaft are required, the device configuration and control become complicated, the power consumption is large, and the cost becomes high. This was done in order to eliminate the disadvantages of the prior art, and the purpose is to provide a moving trolley that can prevent the occurrence of vibrations in the vehicle body and is low in cost.

(D) Means for Solving the Problems The present invention is provided with a vertical movement means for moving a driven wheel up and down relative to a bogie, and a steering means for rotating a pair of drive wheels, when changing the running direction of the bogie. , the driven wheel is lowered by the vertical movement means and 1ψ! The PIJ wheels are raised from the ground, and in this state, the running direction of the drive wheels is changed by the steering means.

(E) Effect According to the above configuration, the drive wheels are separated from the ground when changing direction, so they are not subjected to frictional force from the ground, and therefore vibrations can be prevented from occurring in the insect body.

Further, since the power source used for changing the direction can be provided commonly to the driven wheels, the device configuration can be simplified and the control can be simplified.

(f) Embodiment FIG. 1 shows a mobile cart according to an embodiment of the present invention.

In the figure, swivel casters 11, 12, 13, and 14 whose movement directions are variable are attached to the four corners of the truck 10 so as to be able to move up and down with respect to the truck 10. 15.16 is a trolley IO that is rotatable around the axle center by a steering shaft 17.
is attached to.

FIG. 2 illustrates the vertical movement mechanism of the swivel casters 11, 12 and the drive mechanism of the steering shaft 17. Note that the vertical movement mechanism of the swivel casters 13 and 14 is similarly constructed.

In the figure, the trolley 10 includes an outer frame 10a and an outer frame 10a.
The outer frame 10a and the inner frame 10b have guides 23 for guiding legs 21.22 having swivel casters 11.12 attached to their tips.
They are integrally connected via 24.

Racks 25 and 26 are formed on the legs 21 and 22.

The racks 25 and 26 include bearings 27 and 2g embedded in the outer frame 10a and bearings 2 embedded in the inner frame tab.
A pinion 33.34 is engaged with the shaft 31.32, which is fitted at both ends into the pinion 33.34. Also.

A bevel gear 35.36 is fixed to this shaft 31.32.

The bevel gears 35 and 36 have shafts 39 and 4 whose ends are inserted into bearings 37 and 38 buried in the outer frame 10a.
0 meshes with bevel gears 41 and 42 fixedly installed at the other end of the shaft. Further, a pulley 43.44 is fixedly installed approximately in the center of the shafts 39, 40, and this pulley 43.44
and.

A timing belt 47 is stretched between pulleys 46 fixed to the shaft of a vertical movement motor 45 fixed to the outer frame 10a.

Therefore, the rotational force of the vertical movement motor 45 is.

It is transmitted to pulleys 43 and 44 via a pulley 46 and a timing belt 47, respectively, and is further transmitted to shafts 39 and 4.
0 is transmitted to the shafts 31 and 32 via the bevel gears 41 and 42 and the bevel gears 35 and 36, thereby causing the racks 33 and 34 to rotate in a direction corresponding to the rotation direction of the vertical movement motor 45, and as a result, the legs 21 .22 moves up and down and the ground plane of the swivel caster 11.12 is driven 115.16
It moves up and down relative to that of .

In this case, when the vertical movement motor 45 rotates counterclockwise when viewed from above the trolley 10 in FIG. 1, the timing belt 47 moves in the direction of arrow A, and thereby,
As shown in FIG. 3, the rack 34 rotates in the direction of the solid arrow, so the legs 22 move upward while being guided by the guides 24, and the ground plane of the swivel caster 12 is driven ~15.16 move upward relative to the ground plane. On the contrary, when the vertical movement motor 45 is rotated clockwise, the timing belt 47 moves in the opposite direction B, so that the rack 34 rotates in the direction of the dashed arrow, and the contact surface of the swivel caster 12 is brought into contact with the drive wheel 15.16. move downward relative to the ground plane. In addition, other swivel casters 12, 13 .
14 is also moved up and down in the same manner as the swivel casters 11.

Also, a traveling motor 51 that drives the drive wheels 15 and 16.
．． 52 is attached to a base 53, and one end of the steering shaft 17 is fixed to the center of the base 53.

A gear 54 is fixed to the other end of the steering shaft 17, and this gear 54 meshes with a gear 56 fixed to the shaft of a steering motor 55 fixed to the inner frame 10b. ing.

Therefore, when the steering motor 55 is rotated clockwise when viewed from the top of the figure, the steering shaft 1
7 rotates counterclockwise, and the base 53 rotates accordingly.
rotates, and the traveling direction of the drive wheels 15, 16 rotates counterclockwise. Conversely, when the steering motor 55 is rotated counterclockwise, the steering shaft 17 and the base 53 rotate clockwise, thereby causing the driving wheels 15, 16 to rotate clockwise.

With the above configuration, when the trolley 10 is run, the vertical movement motor 45 sets the height of the contact surfaces of the swivel casters 11 to 14 to be the same as the height of the contact surfaces of the drive wheels 15.16, and ~14 and drive wheels 15,1
The traveling motors 51 and 52 are operated while the trolley 10 is supported by the wheels 6.

Furthermore, when changing the running direction of the five-cart 10, first,
Swivel casters 11 to 14 by vertical movement motor 45
The swivel casters 11-
The height of the ground contact surface of wheel 14 is lower than the height of drive wheels 15 and 16, and the trolley 10 is moved only by the swivel casters 11 to 14.
to prevent the drive wheels 15 and 16 from touching the ground.

In this state, when the steering motor 55 is rotated in a direction opposite to the direction of change in accordance with the amount of change in direction, the driving wheels 15, 16 are rotated in the direction of change by the amount of change in that direction. At this time, since the drive wheels 15 and 16 are away from the ground, no vibration is generated in the truck 10.

After changing the traveling direction of the drive wheels 15 and 16 in this way, the vertical movement motor 45 moves the swivel casters 11 to 14 upward on the trolley 10 to raise the ground surface of the swivel casters 11 to 14. The height is made the same as the height of the ground contact surface of the drive wheels 15.16, so that one bogie 10 can be supported by the swivel casters 11-14 and the drives 11i15.16 and run.

Furthermore, when rotating the truck 10 on the spot, the drive wheels 15 and 16 may be rotated in opposite directions while the truck is running. Further, the rotation direction of each drive wheel 15, 16 is determined by the rotation direction of the truck 10 at that time.

In this way, in this embodiment, the running direction of the trolley 10 can be changed to any direction, and since the drive wheels 15 and 16 are separated from the ground when changing direction, unnecessary vibrations are not caused to the trolley 10. This can be prevented from occurring. Furthermore, when this trolley 10 is used for an unmanned vehicle that moves indoors, such as a cleaning robot, it is possible to prevent floor surfaces such as rugs from being damaged when changing direction.

In addition, since direction change is realized by two motors, the steering motor 55 and the vertical movement motor 45, power consumption during direction change is small, and the number of mechanically heavy motors can be reduced. ,
Since the total weight of the trolley 10 can be reduced and the power consumption during traveling can also be reduced, this is advantageous when the trolley 10 is used as an unmanned vehicle or the like. Furthermore, since there are fewer objects to be controlled when changing direction, control can be simplified.

By the way, in the above-mentioned embodiment, the mechanism for vertically moving the swivel caster, which is a driven wheel, is realized by a motor and a mechanism that transmits its rotational force and converts the rotational force into vertical power. It can also be realized by

In addition, the driven wheels (swivel casters) in the above-mentioned embodiments
The arrangement and number of are not limited thereto. Furthermore, subordinate #ltl! It is also possible to use something other than swivel casters.

(G) Detailed Description of the Invention As described above, according to the present invention, the drive wheels are separated from the ground when changing direction, which prevents the occurrence of vibrations in the vehicle body, and also simplifies the mechanism for changing direction. This has the advantage of reducing costs.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a mobile cart according to an embodiment of the present invention, FIG. 2 is a partial sectional view showing an example of the mechanism, FIG. 3 is a schematic diagram for explaining the vertical movement of the swivel casters, and FIG. Diagram (a)
is a schematic diagram showing the mode in which the conventional device moves straight;
) is a schematic diagram showing how the conventional device changes direction, and the same figure (
(c) is a schematic diagram showing how the conventional device rotates on the spot, and (d) of the same figure is a schematic diagram showing how the conventional device changes direction. DESCRIPTION OF SYMBOLS 10... Trolley, 10a... Outer frame, tab... Inner frame, 11-14... Flexible caster, 15.16... Drive wheel, 17... Steering shaft, 21.22...・Legs, 23.24...Guide, 25.26...Rack,
27.28, 29, 30, 37, 313..., l1
lll uke, 3 I, 32, 39.40...1i'
m, 33.34...Rank, 35.3G, 41.
42... Bevel gear. 43.44.46... Pulley, 45... Vertical motor, 47... Timing belt, 51.52.
・・Traveling motor, 53・・Base, 54.56・
...Gear, 55...Steering motor. Agent Patent Attorney Crest 1) Makoto Figure 1 Figure 0 Figure 3 Figure 4

Claims (1)

[Claims] A movable cart having a pair of driving wheels and a plurality of driven wheels whose traveling direction is variable, comprising a vertical movement means for moving the driven wheels up and down with respect to the cart, and a steering means for rotating the pair of driving wheels. and when changing the running direction of the bogie, the driven wheel is lowered by the vertical moving means to raise the driving wheel from the ground, and in this state, the running direction of the driving wheel is changed by the steering means. A mobile trolley.