JPH0623441Y2 - Unmanned trolley - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to an unmanned trolley, and more particularly to an unmanned trolley having reduced running resistance when changing directions.

"Prior Art" Currently, many types of unmanned bogies that can move in all directions have been devised and put into practical use. An example is shown in FIG. FIG. 5 is a view of the unmanned cart as seen from below. In this figure, 1 is a bottom surface of an unmanned bogie, 2 is a caster attached to the bottom surface 1 of the unmanned bogie, 3 is a driving wheel, and 4 is a turntable to which a driving wheel 3 is mounted. And the turntable 4
Is configured to rotate in any of the directions indicated by the arrows as necessary. On the other hand, the casters 2 described above are used as idle wheels and have a structure as shown in FIG.

That is, 5 is a caster fixing member for attaching the caster 2 to the bottom surface 1 of the unmanned bogie, 6 is a bearing, and 7 is a bearing.
Is an arm formed in a V shape, 8 is a shaft fixed to the end of the arm, 9 is a wheel rotatably supported by the shaft, and x is a swing axis of the arm 7.

The caster used as the idle wheel has the following drawbacks. That is, when the unmanned vehicle changes the traveling direction, the four swinging motions of the arm 7 about the swing axis X occur at the same time, and the wheels 9 slide on the floor surface to change the traveling direction of the unmanned trolley. Running resistance increases. On the other hand, there are compound wheels as shown in FIGS. 6 and 7. This composite wheel is conventionally used as a roller of a conveyor. FIG. 6 is a sectional view of the composite wheel, and FIG. 7 is a view showing the right side surface thereof. In these figures, 10 is a composite wheel frame, and bearing portions 10a, 10b, 10c, 10d are formed at the four corners, respectively. 1
1a, 11b, 11c, 11d is a shaft body, each of the bearing portion 10a,
It is rotatably supported by 10b, 10c and 10d. 12a, 12
b, 12c and 12d are rollers, the roller 12a is fixed to the shaft body 11a, the roller 12b is fixed to the shaft body 11b, and the rollers 12c and 12d are fixed to the axle shafts 11c and 11d, respectively. The ridgeline R of each roller is formed in an arc shape so as to form a part of the circle O shown in FIG. Reference numeral 13 is a hole for rotatably attaching the frame 10 to a shaft (not shown).

This composite wheel rotates around the hole 13, and the four rollers 12a, 12b, 12c, 12d are respectively provided with shafts 11a, 11b, 11c, 1d.
It is configured to rotate around 1d and has two degrees of freedom. Therefore, this composite wheel is, for example, the 8th
As shown in the figure, when the trolley 1 is attached to the trolley bottom surface 1 via the bearing 61 and the shaft body 62, the trolley 1 can change the direction on the floor surface without increasing the running resistance so much. it can.

"Problems to be solved by the invention" However, the above-mentioned compound wheel also has the following drawbacks. That is, when the carriage travels in the direction B shown in FIG. 7, the compound wheels are in the state shown in FIG.
The trolley | bogie 1 runs by any of 12a, 12b, 12c, and 12d.
Further, since the roller diameter is small, the running resistance is large, and even if there is a slight unevenness on the floor surface, the running resistance varies.

This invention was made to eliminate the above problems, and the purpose of this invention is to reduce running resistance and
It is an object of the present invention to provide an unmanned bogie that can improve stability during traveling.

[Means for Solving Problems] An unmanned trolley according to the present invention is attached to a lower portion of the unmanned trolley and is rotated when changing direction, and is attached to the turntable to drive the unmanned trolley. A driving wheel and casters attached to the four corners of the bottom surface of the unmanned trolley, respectively, which rotate about a swing axis and one end of which is located at a point deviated from the swing axis. A caster fixing part for rotatably fixing the swinging arm to the bottom surface at the other end of the swinging arm, a composite wheel frame rotatably supported by the swinging arm, and the composite wheel. A plurality of frames which are rotatably attached to each other in the frame so that their respective rotation axes are in the same plane, and whose traverse lines form part of a circumference centered on the composite wheel frame axis line. It is characterized by comprising four casters composed of one roller.

[Operation] According to this invention, when the unmanned vehicle changes the traveling direction,
An increase in running resistance is prevented by the rotation of any one of the plurality of rollers and the rotation of the composite wheel itself composed of the plurality of rollers, and the swing arm to which the composite wheel is attached is mounted on the neck. Since it rotates about the swing axis, the caster is always automatically adjusted in the direction in which the running resistance is minimized by the moment around the swing axis. For this reason, for example, when it is used for an unmanned bogie, the running resistance during running is reduced and the stability during running is further improved.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1, 2, and 3. The parts corresponding to those in FIGS. 4, 5, and 6 are designated by the same reference numerals.

FIG. 1 is a front view showing the configuration of the embodiment, and shows a state in which a caster according to the present invention is attached to a bottom surface portion 1 of an unmanned bogie. FIG. 2 is a cross-sectional view of the caster shown in FIG. 1 cut by a plane including shafts 11a, 11b, 11c, 11d. FIG. 3 is a view showing a state in which the casters are attached to the four corners of the bottom surface portion 1 of the unmanned cart. In these figures, 101 is the compound wheel described in FIGS. 6 and 7, which is rotatably attached to the swing arm 7 by the shaft 8. The swing arm 7 is the upper end
At 7a, the inner ring 6a of the bearing 6 is fitted. The outer ring 6b of the bearing 6 is fitted in the ring-shaped caster fixing portion 5. A flange 5a is formed at one end of the ring-shaped caster fixing portion 5 and is inserted therein. The flange 5a is provided with a through hole 5b for screwing. The caster fixing portion is fixed to the bottom surface portion 1 of the unmanned trolley by the set screw S so that the caster can be attached. .

Next, the operation of the embodiment will be described.

The unmanned trolley was traveling in the direction of arrow A in FIG. 3, and is now stopped at the position shown in the figure. Then, the traveling direction is being changed to the direction of arrow B. First, the turntable 4 rotates in the direction of arrow C or D. Therefore, the drive wheels 3 and 3 move to the positions indicated by the broken lines.
Next, the drive wheels 3 and 3 are driven. In this case, caster 2
Since the rotation torque for rotating the shaft around the swing axis is large, the caster 2 usually does not swing unless the floor is uneven, and almost any rolling friction is caused by the rotation of one of the rollers 12a to 12d. Rolls on the floor with resistance.
Then, when the running resistance increases due to unevenness on the way and the moment around the swing axis acting on the swing arm becomes larger than the rotation torque, the swing arm rotates and the caster 2 changes direction. . In this state, the swinging resistance is generated, and when the rotation (swinging) of the swinging arm 7 is completed, the casters can roll on the floor with the compound wheels, and the unevenness is overcome only by a slight increase in the running resistance. To run.

As described above, the rotation of the swing arm is caused by the magnitude relationship between the moment about the swing axis due to the resistance when the caster travels on the floor and the rotational torque of the swing arm. It is unlikely that the casters will occur at the same timing, and the four casters swing at different timings.

On the other hand, in the conventional unmanned trolley, when the traveling direction is changed, the casters swing at almost the same time, and the running resistance is significantly increased by the swing resistance. Since the casters swing at different timings, the increase in running resistance is small on average. Furthermore, since the casters roll on the floor by the rotation of the compound wheels themselves during straight running, the running resistance is small, and the occurrence of blurring in the running direction of the unmanned bogie due to variations in running resistance among the casters is reduced. Further, since the running resistance is small, the capacity of the driving motor of the unmanned vehicle may be small, and the power consumption can be reduced.

[Advantages of the Invention] As described above, according to the present invention, a turntable attached to the lower part of the unmanned trolley and rotated when changing the direction, and a driving wheel attached to the turntable and driving the unmanned trolley. A caster attached to each of the four corners of the bottom surface of the unmanned trolley, which rotates about the swing axis, and one end of which is located at a point deviated from the swing axis. A caster fixing portion for rotatably fixing the swinging arm to the bottom surface at the other end of the swinging arm, a composite wheel frame rotatably supported by the swinging arm, and the composite wheel frame A plurality of rotary shafts are rotatably mounted so that they are in the same plane, and the traverse lines form a part of the circumference around the composite wheel frame axis. Since the four casters including the rollers are provided, an increase in running resistance at the time of changing the running direction can be reduced, so that an effect that power consumption required for running can be reduced can be obtained. Further, it is possible to reduce the occurrence of the deviation in the traveling direction due to the variation of the traveling resistance in each caster, and it is possible to obtain the effect of improving the traveling stability.

[Brief description of drawings]

FIG. 1 is a structural diagram showing the construction of an embodiment of the present invention, and FIG.
The figure is a cross-sectional view of the caster in FIG. 1 cut by a plane including the shafts 11a, 11b, 11c, and 11d, and FIG. 3 is a diagram showing the bottom surface of the unmanned bogie to which the caster according to the embodiment is attached. FIG. 4 is a structural diagram showing a configuration of a conventional eccentric caster, FIG. 5 is a diagram showing a bottom portion of an unmanned cart to which a conventional caster is attached, and FIG. 6 is a configuration of a conventional composite wheel of a shaft 11a. , 11b, 11c, and 11d are sectional views cut along a plane, FIG. 7 is a view showing a side surface of the composite wheel, and FIG. 8 is a view showing a mounting state of a conventional composite wheel. 5 ... Caster fixing member, 7 ... Pivoting arm, 10
...... Composite wheel frame, 11a, 11b, 11c, 11d …… Shaft, 12a, 1
2b, 12c, 12d …… Roller, 101 …… Composite wheel

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References Shou 55-158780 (JP, U) Seki 58-30424 (JP, U) Seki 58-93503 (JP, U) Japanese Patent Sho 32- 1751 (JP, B1)

Claims (1)

[Scope of utility model registration request] 1. A turntable attached to a lower portion of an unmanned trolley and rotated when changing directions, driving wheels attached to the turntable and driving the unmanned trolley, and four corners of a bottom portion of the unmanned trolley, respectively. A caster attached to a swinging arm, the swinging arm rotating around a swinging axis, and one end of which is located at a point deviated from the swinging axis, and the neck at the other end of the swinging arm. The caster fixing portion for rotatably fixing the swing arm to the bottom surface portion, the composite wheel frame rotatably supported by the swing arm, and the respective rotation axis lines of the composite wheel frame are in the same plane. 4 casters each of which is rotatably attached and whose traverse line comprises a plurality of rollers forming a part of a circumference centered on the composite wheel frame axis. Unmanned carriage, characterized by comprising.