JP2003312480A - Carriage - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow safe travel even when a step exists on a ground face, to restrain vibration from being generated in the travel, and to allow a turn in a small space even in the travel by a drive. <P>SOLUTION: This carriage 1 comprises a load carrying platform 2 for mounting an article, and a traveling means 10 having casters for traveling on the ground face. The traveling means 10 is provided with a multi-wheeled traveling part 20 having the plurality of casters 28, the traveling part 20 comprises a rotary frame 26 attached with the three casters 28 in its lower face, and a frame holding part 27 for holding the rotary frame 26 rotatable around an axis perpendicular to axles 28a of the three casters 28, and the three casters 28 are attached in positions rotation-symmetric to a rotary shaft of the rotary frame 26. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a truck. More specifically, the present invention relates to a trolley used for serving meals in hospitals and schools, and for carrying luggage indoors and outdoors.

[0002]

2. Description of the Related Art For example, when feeding a patient in each hospital room in a hospital, many trays with meals are accommodated in the car, and while the car is running around each hospital room, the tray is taken out from the car. Have been delivered to. Since such a car usually has four casters at the four corners at the lower end thereof, the wheels of the casters are moved in the front, rear, left, or right directions by rolling on the floor surface. be able to.

[0003]

However, each of the casters used in the conventional catering car has only one wheel. Therefore, of the wheels of the four casters, if one of the wheels of the caster hits a step formed by the floor surface, the wheel cannot roll and the catering car cannot move. When the serving car is light, the step can be overcome by increasing the pushing force of the person, but when the weight of the serving car is heavy, the force of the person cannot overcome the step. Further, even if the weight of the catering car is heavy, in the case of a catering car equipped with a drive device such as a motor, it is possible to get over the step. However, if the catering car tilts when crossing a step, there is a risk that the internal tray will pop out, and if the car height of the catering car is high, there is a possibility that the car may fall over. . Further, even if the step is not such that the rolling of the wheels is hindered, if the floor surface has irregularities, the serving car will vibrate. Then, there is a problem that the liquid substance put in the soup bowl or the like may be spilled, or if the containers are made of glass, the containers may hit each other and be broken. Also, in the case of a catering car that is driven by a drive device, the wheels that are driven by the drive device are usually fixed in the front-back direction, so a wide space is required to change the traveling direction of the catering car. Therefore, it is not possible to change the direction at the desired place.
Therefore, there is a problem in that it is difficult to travel in a passageway of a hospital or the like, and to carry in and out of an elevator.

In view of such circumstances, the present invention allows safe traveling even if there is a step on the ground, suppresses vibration during traveling, and can change direction in a small space even when traveling by a drive device. The purpose is to provide a trolley that is inexpensive.

[0005]

A trolley according to claim 1 is a trolley comprising a loading platform for loading articles and traveling means having wheels for traveling on the ground, the traveling means comprising a plurality of traveling means. A multi-wheel traveling unit having wheels is provided, wherein the multi-wheel traveling unit has a rotating frame having three casters attached to a lower surface thereof, and the rotating frame around an axis perpendicular to the axles of the three casters. And a frame holding portion that holds the three casters in a rotationally symmetric position with respect to the rotation axis of the rotating frame. A trolley according to a second aspect is the invention according to the first aspect, wherein the traveling means is
A support frame having an upper end attached to a lower surface of the luggage carrier, and one end attached to a lower end of the support frame,
A swing arm mounted so as to be swingable up and down with one end as a fulcrum, a wheel attached to the other end of the swing arm, and provided between the support frame and the other end of the swing arm. It is characterized in that it is provided with a buffer caster composed of a damper. According to a third aspect of the invention, in the invention of the second aspect, the damper is an air damper. According to a fourth aspect of the present invention, in the second aspect of the present invention, the support frame is attached to the load platform so as to be rotatable about an axis perpendicular to the axle of the wheel, and the damper is the support frame. And an axle of the wheel. According to a fifth aspect of the invention, in the invention according to the second aspect, the buffer caster has two dampers, and the two dampers are provided on both sides of the wheel. According to a sixth aspect of the present invention, in the vehicle according to the first aspect, the traveling means includes a drive unit for moving on the ground.
It is characterized in that the drive unit is composed of the moving wheels and a drive device for driving the moving wheels. According to a seventh aspect of the present invention, in the vehicle according to the sixth aspect, the drive unit is
It is characterized by comprising a direction changing mechanism for rotating the moving wheel around an axis perpendicular to the axle thereof. According to an eighth aspect of the invention, in the invention according to the eighth aspect, the drive device has a motor, an input shaft connected to a main shaft of the motor, and two drive shafts to which the moving wheels are attached. And a ring gear attached to the outer periphery of the case, a pair of side gears provided in the case and having the drive shaft attached, and a space between the pair of side gears. A pair of pinions that engage with both of the pair of side gears, a differential device that has a center shaft that penetrates through the centers of the pair of pinions and has both ends fixed to the case, and a ring of the differential device. It is characterized by comprising a plurality of gears meshing with the gears and a rotating shaft attached to the plurality of gears. According to a ninth aspect of the invention, in the trolley according to the eighth aspect, one of the two drive shafts is provided with braking means for stopping the rotation of the drive shaft, and the other drive shaft is driven. The shaft comprises an internal output shaft attached to the side gear of the speed reducer and an external output shaft attached to the moving wheel,
A clutch is provided between the internal output shaft and the external output shaft. According to a tenth aspect of the present invention, in the vehicle according to the fourth aspect, the traveling means includes a swing frame to which the multi-wheel traveling section is attached at one end and the moving wheels are attached to the other end. The swing frame is swingably provided in a plane perpendicular to the axle of the moving wheel with a portion between one end and the other end as a fulcrum. The trolley of claim 11 is the trolley of claim 1.
In the invention described in 0, the buffer caster according to claim 2 is provided at a position sandwiching the moving wheel with respect to the multi-wheel traveling portion.

According to the first aspect of the present invention, the multi-wheel running portion 3 is provided.
Even if the wheels of any one of the casters hit a step on the ground and its rolling stops, the rotating frame of the multi-wheel traveling unit rotates around the contact point between the step and the wheel as a fulcrum. However, because it is rotated by the frame support portion, other casters run while bypassing the step. For this reason, the multi-wheel traveling unit does not ride on the step and moves so as to bypass the step and avoids the step. Therefore, even if there is a step on the ground, the trolley can travel smoothly. According to the second aspect of the present invention, when there is unevenness on the ground that does not hinder the traveling of the truck, the damper can absorb the vertical vibration of the wheels of the caster caused by the unevenness. It is possible to suppress vibration. According to the invention of claim 3, since the damper is an air damper, the vibration absorbing ability can be further enhanced. According to the invention of claim 4,
Since it is possible to reduce the offset amount of the wheel axle with respect to the rotation axis of the support frame, it is possible to reduce the blurring of the portion of the loading platform where the cushion casters are provided when the traveling direction of the vehicle is changed. Therefore, the traveling direction of the carriage can be smoothly changed. According to the invention of claim 5, since the dampers are provided on both sides of the wheel, it is possible to suppress the force applied to the damper when the wheel rotates around the support frame. Therefore, the buffer caster can be smoothly rotated around the support frame, the damper can be smoothly operated even during the direction change, and it is possible to prevent the damper from being damaged. According to the sixth aspect of the present invention, the cart can be moved by driving the moving wheels by the drive device, so that the cart can be smoothly run even if the article to be placed on the bed becomes heavy. According to the invention of claim 7, the traveling direction of the moving wheels can be changed by the direction changing mechanism, so that the traveling direction of the carriage can be easily changed. Moreover, since the traveling direction of the traveling wheel can be changed only by rotating the traveling wheel around an axis perpendicular to the axle, the traveling direction can be easily changed even in a narrow space such as a passageway in a hospital or a patient room. It can be carried in and out of the elevator easily. According to the invention of claim 8, when one rotation shaft is rotated by the motor, the ring gear of the differential device is rotated together with the case by the gear to which the rotation shaft is attached. The drive shaft of can be rotated. Therefore, the carriage can be driven by the moving wheels. Further, when the ring gear of the differential gear is rotated, the plurality of gears meshing with the ring gear also rotate, so that the rotating shafts attached to the plurality of gears can also rotate. Therefore, one motor can be used not only as a drive source for running the dolly but also as a power source for activating an accessory device used in the dolly. According to the invention of claim 9, when the clutch is disengaged and the rotation of the other drive shaft is stopped by the braking means, the rotation of the pair of external output shafts can be stopped. Moreover, even if the rotation of the external output shaft is stopped, the ring gear is kept in the rotating state, so that the rotating shafts attached to the plurality of gears are still rotating. Therefore, regardless of whether the rotation of the external output shaft is stopped, that is, the movement of the carriage is stopped,
The output can be taken from the rotating shaft. According to the invention of claim 10, even if there is undulation on the ground, the undulation can be absorbed by the rocking of the rocking frame, so that the cart can be prevented from tilting,
The dolly can be safely driven. Further, since the moving wheel can be always grounded, the vehicle can be surely driven by itself even on a sloping ground. According to the eleventh aspect of the present invention, since the vertical movement of the loading platform that occurs when traveling on the undulating ground can be absorbed by the buffer casters, the dolly vibrates even when traveling on the undulating ground. Can be prevented. Moreover, since the moving wheels, the wheels of the multi-wheel traveling unit, and the wheels of the buffer casters can be always installed, the cart can be safely traveled.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic side view of a carriage 1 of this embodiment. FIG. 2 is a schematic plan view of the trolley | bogie 1 of this embodiment. FIG. 3 shows an example of a trolley for serving food which adopts the trolley 1 of the present invention. As shown in FIGS. 1 and 2, the trolley | bogie 1 of this embodiment is comprised from the loading platform 2 on which an article is mounted, and the traveling means 10 for traveling on the ground. The trolley 1 of the present embodiment can be run not only in the front-rear direction (left-right direction in FIG. 1) but also in the side-direction (direction perpendicular to the paper surface in FIG. 1), but normally the front ( In FIG. 1, the vehicle travels leftward.

As shown in FIG. 1 and FIG.
For loading articles, for example, as shown in FIG. 3, when it is used as a serving cart, a serving shelf A for accommodating a food tray is provided.

As shown in FIG. 1 and FIG.
A pair of left and right brackets 2b, 2b are provided on the lower surface of the rack, and rock between the pair of left and right brackets 2b, 2b so as to be parallel to the lower surface of the loading platform 2 and orthogonal to the front-back direction of the loading platform 2. The moving shaft 2a is attached.

A swing frame 11 of a traveling means 10 is attached to the swing shaft 2a so as to swing up and down with the swing shaft 2a as a fulcrum. At the front end (the left end in FIG. 1) of the swing frame 11, a horizontal mounting frame 11a is attached.
Is provided, and a pair of left and right multi-axis traveling portions 20 are attached to the left and right ends thereof. This multi-axis traveling unit 20
A plurality of known casters 28 are provided, which will be described in detail later.

At the rear end of the swing frame 11, a drive unit 30 is provided.
Is attached. The drive unit 30 is composed of a pair of left and right moving wheels 31 and 31 for traveling the bogie 1 and a drive device 32 for driving the pair of left and right moving wheels 31 and 31. And drive device 32
Includes a motor 33 that is a drive source, and a speed reducer 50 that transmits the rotation of the motor 33 to the pair of left and right moving wheels 31, 31.

Further, the driving device 32 includes the swing frame 11
, And is attached via a direction changing mechanism 35. The direction changing mechanism 35 has a fixed gear 3 having a central axis perpendicular to the axle of the moving wheel 31 fixed to the swing frame 11, that is, perpendicular to the ground or the lower surface of the bed 2.
6, a drive gear 37 meshing with the gear, and a direction changing motor 38 having the drive gear 37 attached to the main shaft. The drive device 32 is rotatably attached to the swing frame 11 about the central axis of the fixed gear 36, that is, about the axis perpendicular to the axle of the moving wheel 31. Therefore, the direction changing motor 38
If the drive wheel 37 is driven, the drive gear 37 rolls around the fixed gear 36, and the drive device 32 is rotated in the horizontal plane, that is, about the axis vertical to the ground along with the movement thereof. The driving direction of the car can be changed to any direction of 360 °.

As shown in FIGS. 1 and 2, when the drive device 32 is attached to the rotary shaft 41 which is rotatable with respect to the swing frame 11, the drive device 32 is provided near the fixed gear 36. A sensor for detecting the rotation angle of the driving device 32 fixed to the device, such as an optical proximity sensor 41a, may be attached, and the operation of the direction changing motor 38 may be controlled by judging the signal from this sensor. In this case, the direction of the moving wheel 31 can be changed accurately and easily.

As shown in FIGS. 1 and 2, the trolley 1
A pair of left and right cushion casters 40, 40 are provided at the rear end (right end in FIGS. 1 and 2). FIG. 5 is a schematic side view of the buffer caster 40 (A), and (B).
It is a schematic front view of the buffer caster 40. As shown in the figure, the cushion caster 40 includes a support frame 41 which is attached to the lower surface of the loading platform 2 vertically and rotatably around an axis. A base end of a swing arm 42 is attached to the lower end of the support frame 41 so that the tip can swing up and down with the base end as a fulcrum, and a wheel 43 is attached to the tip. This wheel 43
A pair of air dampers 44 are attached to both sides of the. The tip of the rod of each air damper 44 is rotatably attached to the support frame 41, and the cylinder body is rotatably attached to the axle 43b of the wheel 43. For this reason, the cushion caster 40 has its wheels 4
When the force to move 3 up and down is applied, the force is applied to the air damper 4
4 can be absorbed.

According to the trolley 1 of the present embodiment having the above-mentioned configuration, if the drive device 32 of the drive unit 30 drives the pair of moving wheels 31, 31, the trolley 1 can be driven by itself. Therefore, even if the article to be loaded on the loading platform 2 becomes heavy, the cart 1 can be smoothly run.

Moreover, by rotating the drive device 32 around the axis perpendicular to the axle of the moving wheel 31 with respect to the luggage carrier 2 by the direction changing mechanism 35, the traveling direction of the moving wheel 31 can be easily changed. Therefore, the traveling direction can be easily changed even in a narrow space such as a passageway in a hospital or a patient room. In particular, carry the truck 1 into the elevator,
When it is carried out, it can be moved at a right angle to the elevator, so that it can be carried in and out easily. If the drive unit 30 is provided in the central portion of the carriage 1, when the drive device 32 rotates in the horizontal plane, the luggage carrier 2 of the carriage 1 is provided.
It is possible to change only the direction of the moving wheel 31 with almost no movement of the vehicle, and conversely, if the direction changing mechanism 35 is operated while the moving wheel 31 is held so as not to move with respect to the ground, It is also possible to rotate only the loading platform 2 on the spot and change its direction.

Further, since a pair of left and right cushion casters 40, 40 are provided at the rear end of the trolley 1, if there are irregularities on the ground that do not hinder the traveling of the trolley 1, the irregularities cause the irregularities. Since the air damper 44 can absorb the vertical vibration of the wheel 43 of the buffer caster 40, the vibration of the luggage carrier 2 can be suppressed. Moreover, since the air damper 44 is used, the vibration absorbing ability is high and the trolley 1 can be traveled very smoothly. Since the air damper 44 is provided between the support frame 41 and the axle 43b of the wheel 43, the offset amount d of the axle 43b of the wheel 43 with respect to the rotation axis of the support frame 41 can be reduced. Therefore, when the traveling direction of the carriage 1 is changed, the turning radius of the wheels 43 of the buffer caster 40 can be reduced, and therefore, when the direction is changed, the portion provided with the buffer caster 40,
That is, it is possible to reduce the blurring of the rear portion of the carriage 1.
Therefore, it is possible to smoothly change the direction of the carriage 1. Moreover, since the air dampers 44 are provided on both sides of the wheel 43, the force applied to the air dampers 44 when the support frame 41 rotates, for example, the air dampers 4
It is possible to prevent the force of bending and twisting 4 from being generated. Therefore, the support frame 41 of the buffer caster 40 can be smoothly rotated, and even if the weight of the article placed on the bed is heavy, it is possible to prevent the buffer caster 40 from malfunctioning.

Further, the multi-wheel traveling unit 20 and the driving unit 30
Are attached to the front end and the rear end of the swing frame 11, respectively. Therefore, as shown in FIG. 6, there is a difference between the height of the ground contact portion of the multi-wheel traveling unit 20 and the height of the moving wheel 31 with respect to the horizontal plane as when traveling on a swelling ground. In the case of, for example, the height of the ground contact portion of the moving wheel 31 is lower than the height of the ground contact portion of the multi-wheel travel portion 20 (FIG. 6 (A)), the ground contact of the multi-wheel travel portion 20 is performed. Even when the height of the ground contact portion of the moving wheel 31 is higher than the height of the portion (FIG. 6C), or even when the moving wheel 31 is recessed ( Figure 6
(B)), the difference in height can be absorbed by the rocking frame 11 rocking. That is, even when the vehicle runs on a ground with undulations, the undulations of the ground can be absorbed by the rocking of the rocking frame 11, so that the trolley 1 can be prevented from inclining and the trolley can be run safely. You can Moreover, since the moving wheel 31, the wheel 28a of the multi-wheel traveling unit 20, and the wheel 43 of the buffer caster 40 can all be grounded at all times, the trolley 1 can be safely traveled and Since the wheel 31 is always in contact with the ground, it can be surely driven by itself even on a sloping ground.

When traveling on a sloping ground, the swing shaft 2a to which the swing frame 11 is attached moves up and down a little and the bed 2 also moves up and down. Since it is provided at a position where the moving wheel is sandwiched with respect to the wheel traveling unit 20, the cargo bed 2 can also absorb the vertical movement by the air damper 44 of the buffer caster 40. Therefore, it is possible to prevent the vibration of the carriage 1 from vibrating even when traveling on a sloping ground.

Further, since the trolley 1 of the present embodiment has the simple structure as described above, the manufacturing cost of the trolley 1 can be reduced. For example, if the trolley 1 is adopted as a trolley for serving, the price of the trolley for serving can be reduced. Can be cheaper.

Now, the multi-wheel traveling unit 20 and the drive unit 3
The speed reducer 50 of No. 2 will be described in detail. First, the multi-wheel traveling unit 20 will be described. FIG. 4 is a schematic front view of the multi-wheel traveling unit 20. In the figure, reference numeral 26 is a multi-wheel traveling unit 20.
The rotating frame of is shown. This rotating frame 26
Has a substantially triangular shape in a plan view, and a rotation shaft 27a of a frame holding portion 27 is erected on the upper surface of the rotation shaft 26 perpendicularly to the rotation frame 26. The rotating shaft 27a is a bearing whose upper end is attached to the lower end of the frame holding unit 27.
It is rotatably attached to the horizontal frame 11a via 27b.

On the lower surface of each apex of the rotating frame 26, there are provided three known casters 28 at positions rotationally symmetrical to each other with respect to the rotating shaft 27a and the axles of the wheels 28a thereof.
28b is attached so as to be orthogonal to the rotating shaft 27a. Incidentally, the known caster 28 is the wheel 28 thereof.
a freely rotates about an axis having a predetermined angle with respect to the axle 28b (in the case of the present embodiment, about an axis parallel to the rotation axis 27a).

Therefore, the carriage 1 is mounted on the multi-wheel traveling unit 20.
When the vehicle travels at the top, the step existing on the ground can be bypassed and traveled as follows. FIG. 7 is a schematic explanatory diagram when the trolley | bogie 1 of this embodiment bypasses the level difference D and travels. As shown in FIG. 7 (A), when the carriage 1 of the present embodiment is traveling with the multi-wheel traveling unit 20 at the head, among the three casters 28 of the multi-wheel traveling unit 20,
When the wheel 28a of any one of the casters 28 hits the step D existing on the ground, the wheel 28a stops rolling.

Then, the rotating frame 26 rotates about the rotating shaft 27a while rotating around the wheel 28a hitting the step D as a fulcrum. Therefore, the carriage 1 does not tilt with respect to the traveling direction before hitting the step D, and continues to move forward while moving laterally (to the right in FIG. 7).
(Fig. 7 (B))

Further, when the carriage 1 advances, the rotating frame 26 further rotates about the rotating shaft 27a while rotating around the wheel 28b hitting the step D as a fulcrum.
Wheel 28a traveling behind the wheel 28a hitting the vehicle
However, it is moved to the front of the wheel 28a hitting the step D, and the multi-wheel traveling unit 20 bypasses the step. (Fig. 7 (C))

As described above, the carriage 1 is connected to the multi-wheel traveling unit 2
If the vehicle is driven with 0 at the top, the multi-wheel traveling unit 20 will move to the step D
Since the vehicle moves around the step D and avoids the step D without riding on the vehicle, the vehicle 1 does not ride on the step D and tilt even if there is a step D on the ground.
Can be run smoothly.

Next, the speed reducer 50 of the drive unit 32 will be described. FIG. 8 is a schematic explanatory diagram of the speed reducer 50. FIG. 9 is a schematic block diagram of the speed reducer 50. In FIG. 8, reference numeral C indicates a hollow outer case C of the speed reducer 50. The outer case C accommodates the hollow case 52 of the differential device 51. A ring gear 53 is attached to the outer circumference of the case 52. Inside the case 52, a pair of left and right side gears 54, 54 are provided, and an inner output shaft 55a of a drive shaft 55 is attached to the center of the rear surface of the side gear 54. The outer end portion of the external output shaft 55b of the drive shaft 55 rotatably supports the external output shaft 55b with respect to the case C,
Further, it is supported by a bearing for supporting the load applied to the external output shaft 55b in the radial direction, that is, in the vertical direction.
The outer end of the external output shaft 55b projects from the outer case C, and the moving wheel 31 is attached to the outer case C.

Of the two drive shafts 55, the right drive shaft 55 has a known clutch 6 such as an electromagnetic tooth clutch between the internal output shaft 55a and the external output shaft 55b.
5 are provided. On the other hand, the internal output shaft 55a of the left drive shaft 55 is formed integrally with the external output shaft 55b,
The internal output shaft 55a is provided with a braking device 66 such as an electromagnetic brake. The braking means 66 may be provided on the external output shaft 55b.

A pair of pinions 56, 56 are provided between the pair of side gears 54, 54. The pinion 56 meshes with both the pair of side gears 54, 54. A center shaft 57 passes through the centers of the pair of pinions 56, 56. The pair of pinions 56, 56 are rotatable with respect to the center shaft 57. Both ends of the center shaft 57 are fixed to the case 52.

A plurality of gears 61 are provided around the case 52 of the differential device 51. These gears 6
Reference numerals 1 and 1 respectively mesh with the ring gear 53 of the differential device 51. One end of a rotary shaft 62 is attached to each of the gears 61, the other end of the rotary shaft 62 projects to the outside of the multi-axis reduction gear 1, and the other end of one rotary shaft 62 is The main shaft of the motor 33 is attached.

Therefore, when the motor 33 is driven, the motor ring gear 53 is rotated via the rotary shaft 62 and the gear 61. Then, together with the ring gear 53, the case 52
Rotates, and the center shaft 57 fixed to the case 52 rotates around the rotation shaft of the ring gear 53.
The pair of pinions 56, 56 attached to the orbit revolve around the rotation axis of the ring gear 53. Then, when the load applied to the pair of left and right drive shafts 55, 55 is the same, the pinion 56, 56 and the pair of side gears 54, 54
Rotate in unison with each other, the left and right drive shafts 55, 55 rotate at the same rotation speed, and the pair of moving wheels 31, 31 rotate at the same rotation speed. Therefore, the moving wheels 31 face each other. The trolley | bogie 1 can be made to run in the direction in which it is moving.

Moreover, since the output can be simultaneously taken out from the rotary shaft 62 to which the motor 33 is not connected, for example, in the case of a trolley for servicing equipped with a servicing shelf A,
If an accessory such as a compressor of a temperature controller for cooling or warming the inside is attached to the rotating shaft 62, power for operating the accessory can also be supplied from the drive unit 30. In this case, since it is not necessary to separately provide a power source for operating the accessory device, the catering trolley can be made compact and its weight can be reduced.

Further, the clutch 32 disconnects the internal output shaft 55a and the external output shaft 55b of the right drive shaft 55, and the braking means 66 stops the rotation of the left drive shaft 55. Stop the rotation of the shaft 55,
The moving wheels 31 can be stopped. Moreover, even in this case, since the ring gear 53 is still rotating, the rotating shaft 62 attached to the plurality of gears 61 is still rotating. Therefore, even when the carriage 1 is stopped, the power source for operating the accessory device can be continuously supplied.

Although only two gears 61 are provided in FIG. 1, the number of gears 61 provided around the differential device 51 is not limited. Furthermore, by changing the number of teeth of each of the plurality of gears 61, it is possible to take out rotational forces with different rotational speeds from one speed reducer 50. Furthermore, of the plurality of rotary shafts 62, one rotary shaft 62 is attached to the swing frame 1
If it is attached to No. 1, the drive device 32 can be rotated by the rotation of the rotary shaft 62 to change the traveling direction of the moving wheel 31.

[0035]

According to the first aspect of the present invention, since the vehicle moves so as to bypass the step and avoids the step, the bogie can be smoothly run even if there is a step on the ground. According to the second aspect of the present invention, it is possible to suppress the vibration of the luggage carrier even if the ground surface has irregularities that do not hinder the traveling of the carriage. According to the invention of claim 3, since the damper is an air damper, the vibration absorbing ability can be further enhanced. According to the invention of claim 4, when changing the traveling direction of the carriage, it is possible to reduce the blurring of the portion provided with the buffer casters, and to smoothly change the traveling direction of the carriage. According to the invention of claim 5, the cushion caster can be smoothly rotated around the support frame, and further, it is possible to prevent the damper from being damaged. According to the invention of claim 6, even if the article to be placed on the bed becomes heavier, the cart can be smoothly moved. According to the invention of claim 7, the traveling direction of the carriage can be easily changed, and further, the traveling direction can be easily changed even in a narrow space. According to the invention of claim 8, if the pair of drive shafts is rotated by the differential device, the carriage can be made to travel by the moving wheels, and only one motor is used as a drive source for making the carriage travel. Instead, it can also be used as a power source to operate auxiliary equipment used in the dolly. According to the invention of claim 9, the output can be taken out from the rotary shaft regardless of the stop of the rotation of the external output shaft. According to the invention of claim 10, even if there is undulation on the ground, it is possible to prevent the trolley from tilting, to safely drive the trolley, and to reliably drive the trolley itself. According to the eleventh aspect of the present invention, since the bogie does not remain swinging after passing through the portion having the undulation, the bogie can be safely driven.

[Brief description of drawings]

FIG. 1 is a schematic side view of a carriage 1 of the present embodiment.

FIG. 2 is a schematic plan view of the trolley | bogie 1 of this embodiment.

FIG. 3 is an example of a trolley for servicing, which adopts the trolley of the present invention.

FIG. 4 is a schematic front view of a multi-wheel traveling unit 20.

5 (A) is a schematic side view of the buffer caster 40, and (B) is a schematic front view of the buffer caster 40. FIG.

FIG. 6 is a schematic explanatory diagram when the trolley | bogie 1 of this embodiment travels on the undulating ground.

FIG. 7 is a schematic explanatory diagram when the trolley | bogie 1 of this embodiment bypasses the level | step difference D and travels.

FIG. 8 is a schematic explanatory diagram of a speed reducer 50.

FIG. 9 is a schematic block diagram of a speed reducer 50.

[Explanation of symbols]

1 dolly 2 loading platform 11 rocking frame 20 Multi-wheel running section 26 rotating frames 27 frame holder 28 casters 30 Drive 31 Wheels for movement 32 Drive 40 buffer casters 41 Support frame 42 Swing arm 43 wheels 44 Air damper 50 reducer 51 Differential 52 cases 53 ring gear 54 side gear 55 Drive shaft 55a Internal output shaft 55b External output shaft 56 pinion 57 Center axis 61 gears 62 rotation axis 65 clutch 66 control means

Continued front page    (72) Inventor Tsutomu Miyamoto             1-7-20 Togoshi, Shinagawa-ku, Tokyo Taniko Co., Ltd.             Inside the company (72) Inventor Kenji Takahashi             1-7-20 Togoshi, Shinagawa-ku, Tokyo Taniko Co., Ltd.             Inside the company F-term (reference) 3D050 AA01 BB02 DD01 DD03 EE03                       EE11 KK06 KK14

Claims (11)

[Claims] 1. A trolley comprising a loading platform for loading articles and a traveling unit having casters for traveling on the ground, wherein the traveling unit comprises a multi-wheel traveling unit having a plurality of casters. A multi-wheel traveling unit, a rotating frame having three casters attached to a lower surface thereof, and a frame holding unit for holding the rotating frame rotatably around an axis perpendicular to the axles of the three casters; The bogie, wherein the three casters are mounted at positions symmetrical to the rotation axis of the rotating frame. 2. The traveling means has an upper end attached to a support frame attached to the lower surface of the loading platform, and one end attached to the lower end of the support frame, and is attached so as to be vertically swingable about the one end. A buffer caster including a swing arm, a wheel attached to the other end of the swing arm, and a damper provided between the support frame and the other end of the swing arm is provided. The trolley according to claim 1. 3. The trolley according to claim 2, wherein the damper is an air damper. 4. The support frame is rotatably attached to the platform about an axis perpendicular to the axle of the wheel, and the damper is provided between the support frame and the axle of the wheel. The trolley according to claim 2, characterized in that 5. The bogie according to claim 2, wherein the cushion caster has two of the dampers, and the two dampers are provided on both sides of the wheel. 6. The traveling means includes a drive unit for moving on the ground, and the drive unit includes the moving wheels and a drive device for driving the moving wheels. The trolley according to claim 1. 7. The bogie according to claim 6, wherein the drive unit includes a direction changing mechanism for rotating the moving wheel around an axis perpendicular to the axle thereof. 8. The drive device comprises a motor, an input shaft connected to a main shaft of the motor, and a speed reducer having two drive shafts to which the moving wheels are attached. A case, a ring gear attached to the outer periphery of the case, a pair of side gears provided in the case and having the drive shaft attached, and a pair of side gears provided between the pair of side gears A pair of pinions that mesh with each other, a differential device that has a center shaft that penetrates through the centers of the pair of pinions and has both ends fixed to the case, and a plurality of gears that mesh with the ring gear of the differential device,
The trolley according to claim 6, comprising a rotary shaft attached to the plurality of gears. 9. One of the two drive shafts is provided with braking means for stopping the rotation of the drive shaft, and the other drive shaft is attached to a side gear of the speed reducer. 9. The internal output shaft according to claim 1, and an external output shaft attached to the moving wheel, wherein a clutch is provided between the internal output shaft and the external output shaft. Dolly. 10. The traveling means comprises a swing frame having the multi-wheel traveling portion attached to one end and the moving wheel attached to the other end, the swing frame including the one end and the other end. The trolley according to claim 4, wherein the trolley is provided so as to be swingable in a plane perpendicular to the axle of the moving wheel with a portion between the ends as a fulcrum. 11. The bogie according to claim 10, wherein the cushion caster according to claim 2 is provided at a position sandwiching the moving wheel with respect to the multi-wheel traveling portion.