Vehicle body structure of autonomous traveling vehicle

To provide a vehicle body structure for an autonomous traveling vehicle equipped with wheels arranged to a chassis thereof, including; side frames arranged on both sides in a width direction of the chassis and each extended in a longitudinal direction of the chassis; a first drive unit having a drive motor, a drive shaft, a first pulley and a first pulley box; a second drive unit having an axle for supporting the wheel and a second pulley and a second pulley box; and an endless belt. The first pulley box has a first opening formed on a side surface, with respect to an axial direction of the drive shaft while the second pulley box has a second opening formed on a side surface with respect to an axial direction of the axle. The vehicle body structure includes bearing covers for covering the first and second openings.

This Nonprovisional application claims priority under 35 U.S.C. § 119(a) on Patent Application No. 2015-162872 filed in Japan on 20 Aug. 2015 and Patent Application No. 2016-124785 filed in Japan on 23 June 2016, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The present invention relates to a vehicle body structure of an autonomous traveling vehicle, in particular relating to a vehicle body structure of an autonomous traveling vehicle that travels on wheels attached to the chassis.

(2) Description of the Prior Art

Conventionally, there has been a known autonomous traveling vehicle that has two wheels arranged in the longitudinal direction on each side, the two wheels being coupled by a drive transmitting means to drive.

When the drive system of such an autonomous traveling vehicle is configured to use an endless belt as a drive transmitting means, replacement of the endless belt has to be done by dismounting the drive unit from the chassis and disassembling the unit to take out the endless belt. This process needs very complicated tasks including detachment and attachment of the drive unit and disassembly and assembly of the drive unit, making maintenance extremely difficult.

As a prior art technology to deal with the above situation, there has been a disclosure as to improvement in maintenance of a crawler type driving mechanism having crawlers that are arranged in the longitudinal direction or the vehicle and transmit drive similarly to the endless belt. In this mechanism, the crawlers are configured to be removable from the vehicle chassis to thereby achieve improvement in maintenance (see Patent Document 1).

PRIOR ART DOCUMENTS

Patent Documents

Patent Document 1

OUTLINE OF THE INVENTION

Problems to be Solved by the Invention

However, recently there have beers demands for miniature autonomous traveling vehicles that can be easily controlled and efficiently used in narrow areas.

Under these circumstances, in the field of autonomous traveling vehicles that are smaller compared to those adopting the crawler type driving mechanism according to Patent Document 1, four-wheeled autonomous traveling vehicles using skid-steer drive that enables steering and turning at a fixed point without needing a large steering space, by actuating the left and right wheels at different rates of revolutions, have of ten been adopted.

However, when the autonomous traveling vehicle of this kind is constructed so that, the endless belts for driving the wheels can be attached to and detached from the side of the chassis, the rotational axle of the wheels needs to take a cantilevered structure, causing a problem that the support of the wheels becomes unstable.

SUMMARY OF THE INVENTION

In view of the above problem, it is therefore an object of the present invention to provide a vehicle body structure for autonomous traveling vehicle which is excellent in maintenance performance free from the problem of the support of the wheels becoming unstable.

Means for Solving the Problems

In order to achieve the above object, the vehicle body structure of autonomous traveling vehicle according to the present invention is configured as follows:

The first aspect of the present invention resides in a vehicle body structure for an autonomous traveling vehicle equipped with first and second wheels attached to a chassis, comprising:

first and second side frames arranged on both sides in a width direction of the chassis and each extended in a front-to-rear direction of the chassis;

a first drive body;

a second drive body; and,

a third drive transmitting member (e.g., an endless belt), and

the first drive body comprising;a driver used for driving a first wheel;a drive shaft for driving the first wheel;a first drive transmitting member (e.g., a first pulley) to which drive force is transmitted from the drive shaft; anda first drive transmitting member casing for accommodating the first drive transmitting member,

the second drive body comprising:an axle for supporting a second wheel;a second drive transmitting member (e.g., a second pulley) that transmits drive force to the axle; anda second drive transmitting member casing foraccommodating the second drive transmitting member;
wherein

the third drive transmitting member couples the first drive transmitting member and the second drive transmitting member to transmit drive force,

the first drive body and the second drive body are arranged on the same side frame,

the first drive transmitting member casing has a first opening portion on a side surface with respect to an axial direction of the drive shaft,

the second drive transmitting member casing has a second opening portion, on a side surface with respect to an axial direct ion of the axle,

the vehicle body structure is equipped with a covering member that covers the first and second opening portions, and

the covering member includes:a first bearing part that rotatably supports the drive shaft; anda second bearing part that rotatably supports the axle.

The second aspect of the present invention resides in that the first opening portion is formed to have size greater than an outside diameter of the first drive transmitting member, and the second opening portion is formed to have size greater than the outside diameter of the second drive transmitting member.

The third aspect of the present invention resides in that the first opening portion has a first cutout portion at one side end on the side surface of the first drive transmitting member casing so as to allow the third drive transmitting member to pass through the first cutout portion and the second opening portion has a second cutout portion at one side end on the side surface of the second, drive transmitting member casing so as to allow the third drive transmitting member to pass through the second cutout portion.

The fourth aspect of the present invention resides in that an attachment of the covering member to the first opening portion and/or the second opening portion is formed in a tapered attachment configuration.

The fifth aspect of the present invention resides in that the first bearing part and/or the second bearing part arranged in the covering member uses a cone bearing.

The sixth aspect of the present invention resides in that the third drive transmitting member is arranged on an interior side of the chassis than the first side frame and/or the second side frame, and the first side frame and/or the second side frame are/is equipped with a covering member that encloses the third drive transmitting member.

The seventh aspect of the present invention resides in further inclusion of a moving mechanism in the first side frame and/or the second side frame for moving the second drive body forwards and backwards along the first side frame and/or the second side frame relative to the first drive body, and that attachment and detachment of the third drive transmitting member is performed by moving the second drive body forwards and backwards by means of the moving mechanism.

The eighth aspect of the present invention resides in that the first wheel and/or the second wheel include/includes a tire member and a wheel member supporting the tire member.

the covering member is removably attached to the first drive transmit ting member casing and the second drive transmitting member casing by a fastener, and

the wheel member is formed with a wheel opening portion at a position opposite to the fastener for attaching the covering member so as to allow attachment and detachment of the fastener from an outer side of the wheel member regarding the chassis.

Advantages of the Invention

According to the first aspect of the present invention, while the wheels can be supported stably, dismounting of the covering member makes it possible to easily attach and detach the third drive transmitting member from the first drive transmitting member casing and the second drive transmitting member casing. As a result, it is possible to realize a vehicle body structure for autonomous traveling vehicle that is excellent in maintenance performance.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Modes for Carrying Out the Invention

The First Embodiment

Now, embodiments of vehicle body structure of autonomous traveling vehicle of the present invention will be described with reference to the drawings.

FIG. 1shows one example of an embodied mode of the present invention and is an illustrative diagram in a plan view showing an overall configuration of a vehicle body structure of an autonomous traveling vehicle according to the first embodiment of the present invention;FIG. 2is an illustrative diagram in a side view showing the overall configuration of the vehicle body structure of the autonomous traveling vehicle;FIG. 3is an illustrative diagram showing a state where a wheel has been attached to a first drive unit forming the autonomous traveling vehicle;FIG. 4is a side sectional view showing the arrangement of the first drive unit and wheel;FIG. 5is a front view showing a configuration of a bearing cover and a protecting cover of the first drive unit;FIG. 6is a side sectional view showing a configuration of the bearing cover;FIG. 7is a front view showing a configuration of a first pulley box of the first drive unit;FIG. 8is a side sectional view showing a configuration of the first pulley box;FIG. 9is a front view showing a configuration of a bearing cover of a second drive unit forming the autonomous traveling vehicle;FIG. 10is a side sectional view showing a configuration of the bearing cover;FIG. 11is a front view showing a configuration of a second pulley box of the second drive unit;FIG. 12is a side sectional view showing a configuration of the second pulley box; and,FIG. 13is an illustrative diagram showing an opening portion of the first pulley box.

A vehicle body structure1for autonomous traveling vehicle according to the first embodiment is a vehicle body structure for an autonomous traveling vehicle that travels by wheels3arranged on a chassis2, as shown inFIG. 1.

Herein, an autonomous traveling vehicle is an apparatus that autonomously travels on a mechanical or program basis without being controlled by human decision-making. A known example of the autonomous traveling vehicle is an autonomous industrial truck for transporting some stuff in a factory.

The vehicle body structure1of autonomous traveling vehicle of the first embodiment includes, mainly, the chassis2, wheels (first wheels and second wheels)3, side frames4(4R,4L), drive motors (driving part)5for driving wheels (first wheels)3, speed reducers (drive transmitters)6, drive shafts7for driving wheels (first wheels)3and axles6for supporting wheels (second wheels)3.

The configuration of the vehicle body structure1of the autonomous traveling vehicle of the first embodiment will be described with reference to the drawings.

The chassis2that constitutes the vehicle body structure1of the autonomous traveling vehicle is given in a rectangular form with its long side oriented in the front-to-rear direction. A pair of side frames4R and4L extending in the longitudinal direction of the chassis are arranged on each side in the width direction of the chassis.

The side frames4R and4L are formed in a rectangular frame-shaped configuration.

The side frames4R and4L may be configured by tubular structural members having a rectangular section, for example.

In the first embodiment, there are first drive units (first drivers)20each including a drive motor5, speed reducer (e.g., gear box)6and drive shaft7as an integrated unit and second drive units (second drivers)30each including an integrated unit structure for rotatably supporting an axle8. InFIGS. 1 and 2, wheels3have been mounted to the first drive units20and the second drive units30. A reference numeral FL (FIG. 2) designates an indoor floor surface or outdoor ground surface. Each wheel3is a tired wheel having a tire31and a wheel32, but can be a tireless wheel.

The first drive unit20and the second drive unit30are coupled by an endless belt (third drive transmitting member43to transmit drive.

Provided on the drive shaft7of the first drive unit20is a first pulley (first endless member driver)41that transmits drive to the endless belt43.

Provided on the axle8of the second drive unit30is a second pulley (second endless member driver)42that is driven by the endless belt43to drive the axle8.

The first drive unit20includes a first pulley box (first drive transmitting member casing)51that supports the drive shaft7and accommodates the first pulley41, as shown inFIG. 3.

As shown inFIGS. 7 and 8, the first pulley box51has an opening53(first opening portion) on the side facing the wheel3side with respect to the direction in which the drive shaft7extends (the axial direction) so as to allow access to the endless belt43for its attachment and removal as well as having a bearing cover (covering member of cover portion)60(FIGS. 5 and 6) for covering the opening53. A bearing72(FIGS. 5 and 6) for rotatably supporting the drive shaft7is provided on the drive shaft7. When the bearing-cover60is attached to the opening53, the bearing72snugly fits into the center hole of the bearing cover60so as to support and position the bearing72by the hearing cover60.

In the first drive unit20, the first pulley box51accommodates the first pulley41while the drive shaft7is rotatably supported at both ends, i.e., by a bearing71(FIGS. 3, 4 and 6) arranged on the side facing the drive motor5(the interior side of the side frame) and by the bearing (the first bearing portion)72provided with the bearing cover50.

Integrally attached to the first pulley box51is the speed reducer6, which is disposed on the more interior side of the vehicle body than the side frame4. An outer dimension in the vertical direction of the speed reducer6is specified to be smaller than an outer dimension of the first pulley box51. That is, when the first drive unit20is attached to the side frame4, the speed reducer6is passed through and inserted inside the side frame4so as to be set inside the chassis2while the first pulley box51is arranged within the side frame4.

The second drive unit30includes, as shown inFIG. 4, a second pulley box (second drive transmitting member casing)52that supports the axle8and accommodates a second pulley42.

As shown inFIGS. 11 and 12, the second pulley box52has an opening53(second opening portion) formed on the side facing the wheel3side with respect to the axial direction of the axle8so as to allow access to the endless belt43for its attachment and removal as well as having a bearing cover60(FIGS. 9 and 10) for covering the opening53. As shown inFIGS. 10 and 12, a bearing72for rotatably supporting the axle8is provided on the axle8. When the bearing cover60is attached to the opening53, the bearing72snugly fits into the center hole of the bearing cover60so as to support and position the bearing72by the bearing cover60.

Further, in the first pulley box51and/or the second pulley box52, it is also possible to provide a configuration where the bearing72is fixed beforehand to the bearing cover60.

Moreover, the hole itself in the bearing cover60that supports the drive shaft7or axle8may be integrally formed with a bearing member such as a sliding bearing so as to provide a bearing function.

In the second drive unit30, the second pulley box52is configured so as to accommodate the second pulley42while the axle8is rotatably supported at both ends, i.e., by a bearing71arranged on a side surface of the far side from the wheel (the interior side of the side frame) and by the bearing72(the second bearing portion) provided with the bearing cover60.

When the second drive unit30is attached to the side frame4, the second pulley box52is arranged sidewards from the outer side of the side frame4and into the inside of the side frame4.

Openings53of the first pulley box51and the second pulley box52are formed to have size greater than the outside diameter of the first pulley41or the second pulley, as shown inFIGS. 7, 11 and 13.

Side surface of the first pulley box51and the second pulley box52each has a cutout portion54(first cutout portion, second cutout portion) (FIGS. 7, 11 and 13) formed on the one side edge thereof so as to allow endless belt43to pass through.

As shown inFIGS. 1 and 2, the first drive unit20and the second drive unit30are arranged so as to be integrally attachable to, and detachable from, the side frame4R or4L on the same side, from the outer side of the vehicle body.

Provided on the vehicle's side face outside the side frame4R/4L is a protecting cover (covering member)80for covering the endless belt43arranged inside the side frame4R/4L, as shown inFIGS. 1 and 2.

Protecting cover80is disposed so as to enclose the space between the first drive unit20and the second drive unit30on the side frame4R/4L.

As has been described heretofore, the vehicle body structure1for autonomous traveling vehicle according to the first embodiment includes side frames4R and4L; first drive units20each including an integrated unit of drive motor5, speed reducer6, drive shaft first pulley41and first pulley box51; second drive units30each including an integrated unit structure of axle8, second pulley42and second pulley box52; and endless belt43that couples the first pulley41and the second pulley42.

In the vehicle body structure1for autonomous traveling vehicle, the first drive unit20and the second drive unit30are each integrally attached in a removable manner to the same side frame4R/4L.

Further, the drive shaft7and axel8each is supported rotatably at two points located along their corresponding axis.

Moreover, the first pulley box51and the second pulley box52have the sideward opening53on the outer side surface of the vehicle body with respect to the axial direction of the drive shaft7or axle8.

Further, the vehicle body structure1for autonomous traveling vehicle has the bearing cover60that covers the opening53.

Provision of the bearing72for rotatably supporting the drive shaft7or axle3in the bearing cover60makes it possible to stably support the wheel3and facilitates attachment of the endless belt43to, and removal from, the first and second pulley boxes51and52, by dismounting bearing covers60. Since this configuration enables easy maintenance in replacing the endless belt43, bearings72and the like without dismounting the first drive unit20and/or the second drive unit30, it is possible to realize a vehicle body structure for autonomous traveling vehicle excellent in maintenance performance.

Further, in the first embodiment, provision of the protecting cover80on the exterior side surface of the side frame4R/4L prevents penetration of mud and the like into the inside of the side frame4R/4L, hence makes it possible to protect the endless belt43.

Also, in the first embodiment, formation of the cutout54connecting to the opening53in the first and second pulley boxes51and52further facilitates attachment and detachment of the endless belt43.

It is possible by providing openings53alone to attach and remove the endless belt43without provision of cutouts54in the first and second pulley boxes51and52. For example, sizing the configuration of the opening53to be greater than the outside diameter of the first pulley41or second pulley42, makes it possible to facilitate attachment and detachment of the endless belt43.

The Second Embodiment

Next, the second embodiment of the present invention will be described with reference to the drawings.

FIG. 14is an illustrative diagram showing the arrangement of attachment between a pulley box and a bearing cover for constituting a vehicle body structure for autonomous traveling vehicle according to the second embodiment of the present invention.

Here, in the vehicle body structure for autonomous traveling vehicle in the second embodiment, the same components as those in the vehicle body structure1for autonomous traveling vehicle of the first embodiment are allotted with the same reference numerals without description.

As shown inFIG. 14, in a vehicle body structure200for autonomous traveling vehicle according to the second embodiment, the arrangement of attachment of a bearing cover260to first and second pulley boxes251and252has a tapered configuration.

In the second embodiment, the attachment part261aof the bearing cover260is tapered toward the distal end. The attachment part251a(252a) of the first pulley box251(or the second pulley box252) mating the attachment part251ais formed to be open as tapering toward the interior of the vehicle body.

The second embodiment thus configured enables easy attachment and detachment of the bearing cover260relative to the first pulley box251and second pulley box252.

The Third Embodiment

Next, the third embodiment of the present invention will be described with reference to the drawings.

FIG. 15is an illustrative diagram showing the arrangement of attachment between a pulley box and a bearing cover for constituting a vehicle body structure for autonomous traveling vehicle according to the third embodiment of the present invention.

Here, in the vehicle body structure for autonomous traveling vehicle in the third embodiment, the same components as those in the vehicle body structure1for autonomous traveling vehicle of the first embodiment are allotted with the same reference numerals without description.

As shown inFIG. 15, in a vehicle body structure300for autonomous traveling vehicle according to the third embodiment, the arrangement of attachment of a bearing cover360to first pulley box351and second pulley box352has a tapered configuration while a bearing372on the bearing cover360side employs a cone bearing.

In the third embodiment, the attachment part361aof the bearing cover360is tapered toward the distal end. The attachment part351a(352a) of the first pulley box351(or the second pulley box352) mating the attachment part361ais formed to be open as tapering toward the interior of the vehicle body.

Further, in the third embodiment, the bearing372is constructed so that the inner ring372ais attached on the drive shaft7or axle8whereas the outer ring372bis attached to the bearing cover360.

The third embodiment thus configured enables easy attachment and detachment of the bearing cover360relative to the first pulley box351and second pulley box352as well as enabling easy positioning the axes of the drive shaft7and the axle8.

The Fourth Embodiment

Next, the fourth embodiment of the present invention will be described with reference to the drawings.

FIG. 16is an illustrative diagram showing a configuration of a bearing cover of the pulley box and a protecting cover of the side frame for constituting a vehicle body structure for autonomous traveling vehicle according to the fourth embodiment of the present invention.

Here, in the vehicle body structure for autonomous traveling vehicle in the fourth embodiment, the same components as those in the vehicle body structure1for autonomous traveling vehicle of the first embodiment are allotted with the same reference numerals without description.

As shown inFIG. 16, a vehicle body structure400for autonomous traveling vehicle according to the fourth embodiment includes a protecting cover460that integrally provides both the functions of the protecting cover for protecting the endless belt and the bearing cover.

In the fourth embodiment, the protecting cover460serving as both the bearing cover for the first pulley box51and the protecting cover for the side frame4R/4L and a bearing cover68of the second pulley box52constitute the protective enclosure for protecting the interior of the side frame4R/4L in the autonomous traveling vehicle. Designated at62are fasteners.

According to the fourth embodiment thus configured, it is possible to easily perform attachment and detachment work of the protecting cover460on the basis of the position of the drive shaft7of the first pulley box51.

The Fifth Embodiment

FIG. 17is an illustrative diagram, as viewed from the side, showing an attachment state of tired wheels to the drive units in the vehicle body structure for autonomous traveling vehicle according to the fifth embodiment of the present invention.

In the vehicle body structure for autonomous traveling vehicle in the fifth embodiment, the same components as those in the vehicle body structure1for autonomous traveling vehicle of the first embodiment are allotted with the same reference numerals without description.

A vehicle body structure500for autonomous traveling vehicle according to the fifth embodiment relates a configuration of wheels503attached to the first drive unit20and second drive unit30. The wheel503is formed of a tire531and a wheel532for supporting the tire531. The wheel532with the tire531mounted thereon is formed with a plurality of wheel openings533at positions opposite to fasteners62that fix the bearing covers60attached to the first drive unit20and second drive unit30.

The wheel opening533is formed with a size that allows access to the fasteners62for attachment and detachment from the outside when the wheel is positioned at the predetermined position in the state where the wheels503remain mounted on the first, driving unit20and second driving unit30, as shown inFIG. 17.

As constructed above, in the vehicle body structure500for autonomous traveling vehicle of the fifth embodiment the wheel532of wheel503is formed with a plurality of wheel openings533at positions opposite to the fasteners62for attaching the bearing covers60attached to the first drive unit20and second drive unit30. This arrangement makes it possible to attach and detach the fasteners62through the wheel openings533, hence it is possible to dismount the bearing covers60and perform attachment and detachment of the endless belt43through the opening53.

The Sixth Embodiment

Next, the sixth embodiment of the present invention will be described with reference to the drawings.

The sixth embodiment gives a specific example where maintenance of the vehicle body structure for autonomous traveling vehicle is performed from the side of the vehicle.

FIG. 18is an illustrative diagram as viewed from the side, showing a configuration of a vehicle body structure for autonomous traveling vehicle of the sixth embodiment of the present invention;FIG. 19is an illustrative diagram as viewed from the side, shoving a configuration of the vehicle body structure when the wheels have been taken out from the autonomous traveling vehicle;FIG. 20is an illustrative diagram as viewed from the side, showing a state where the protecting cover has been removed from the vehicle body structure;FIG. 21is an illustrative diagram as viewed from the side, showing a state where a bearing cover has been removed from the vehicle body structure;FIG. 22is an illustrative diagram as viewed from the side, showing a state where an endless belt is removed from the vehicle body structure; and,FIG. 23is an illustrative diagram showing a configuration of a moving means for moving the second drive unit in order for attachment and detachment of the endless belt in the vehicle body structure.

Here, in the vehicle body structure for autonomous traveling vehicle in the sixth embodiment, the same components as those in the vehicle body structure1for autonomous traveling vehicle of the first embodiment are allotted with the same reference numerals without description.

Referring to the drawings, the sixth embodiment will be explained about maintenance work of a vehicle body structure600for autonomous traveling vehicle by taking an example of replacing the endless belt43.

As shown inFIG. 18, when the vehicle body structure1for autonomous; traveling vehicle with its side surface covered by a protecting cover80is maintained, wheels3are dismounted first as shown inFIG. 19, so that the first drive unit20, second drive unit30and protecting cover80are exposed to allow easy access to the vehicle body structure1from the side.

Then, when the interior components of the chassis inside of the side frame4need to be maintained, the protecting cover80is removed as shown inFIG. 20to open the interior of the side frame4and thereby expose the endless belt43and others.

Then, when the endless belt43arranged inside of the side frame4needs to be removed, the bearing covers60are detached from the first drive unit20and the second drive unit30to open the opening53and cutout portion54, as shown inFIG. 21.

Then, for example, by loosing the attachment state of the second drive unit30and, moving the second drive unit30toward the first drive unit20(in the direction of the arrow), the endless belt43is slacked off, as shown inFIG. 22. Then, the endless belt43is dismounted at both ends from the first pulley41and second pulley42, whereby the belt can be taken out from the first drive unit20and second drive unit30through the opening53and cutout portion54.

As the moving mechanism for moving the second drive unit30forwards or backwards relative to the first drive unit20, for example, as shown inFIG. 23, an attachment position adjusting screw90may be provided at the end of the side frame4and a threaded hole corresponding to the attachment position adjusting screw90is arranged in the second drive unit30, whereby the second drive unit30can be moved forwards and backwards along the side frame4as the attachment position adjusting screw90is turned around.

Though the embodiments have been described heretofore, the present invention should not be limited to the above embodiments and various changes can be made within the range specified in the scope of claims. That is, any embodied mode obtained by combination of technical means modified as appropriate within the scope of claims should be included in the technical scope of the present invention.

DESCRIPTION OF REFERENCE NUMERALS