JP2007210408A - Unmanned carrier car - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an unmanned carrier car capable of constantly grounding four caster wheels on a travelling road surface and keeping tightening pressure of a chain constant. <P>SOLUTION: This unmanned carrier device has an upper part frame 17 fixed on a load carrying platform to load a load material, a driving part 12 arranged below the upper part frame 17 and having a driving wheel 11 and a lower part frame 16 fixed on the driving part 12 and is devised to constantly ground the caster wheels mounted on the load carrying platform on the travelling road surface by maintaining the load carrying platform horizontal by interposing a compression coil spring 18 and interposing a connecting mechanism 20 between the upper part frame 17 and the lower part frame 16. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an automated guided vehicle, and more particularly to an automated guided vehicle capable of maintaining a load carrier horizontally by always grounding four caster wheels to a traveling road surface.

  As an automated guided vehicle, it has two pairs of wheels that support the stand and a pair of drive wheels that are arranged in the center of the stand, and is driven by the unevenness of the floor surface by elastically biasing the drive wheels downward Examples include avoiding a case where the wheels are lifted and the driving force is not transmitted, or that almost all of the load of the load is applied to the driving wheels and the driving load becomes excessive (see, for example, Patent Document 1).

  An example of the drive mechanism of the above-described automatic guided vehicle is shown in FIG. As shown in this figure, the drive mechanism 50 of the automatic guided vehicle includes a pair of drive wheels 51 and a drive unit 52 that drives the drive wheels 51. The drive unit 52 incorporates two drive motors (not shown), and the drive force generated by each drive motor is individually transmitted to the drive wheels 51 via the sprocket 53, the chain 54 and the sprocket 55. Has been. A first frame 57 fixed to a cargo bed (not shown) via a tubular member 56 is fixed to the upper portion of the drive unit 52. A compression coil spring 58 is disposed in the tubular member 56. The compression coil spring 58 is locked to the first frame 57 at an upper portion thereof, and is locked to the driving wheel 51 at a lower portion thereof. The drive wheel 51 is urged downward by the compression coil spring 58.

JP 2004-249895 A

However, in the automatic guided vehicle having the drive mechanism 50 as described above, the vertical movement of the drive wheel and the rotational movement around the tubular member are performed at the same place. If the car is bent and transported, or if only one drive wheel moves up and down due to unevenness on the floor, etc., the first frame will swing in the front and rear direction and the horizontal direction. There was a possibility that any of the four caster wheels that were installed did not touch the road surface.
In addition, since the center of the rotation axis of the drive wheel moves in the vertical direction and the distance between the drive wheel and the sprocket changes, the chain tension pressure does not become constant.

  Accordingly, the present invention has been proposed in view of the above-described problems, and an object thereof is to provide an automatic guided vehicle in which four caster wheels can always be brought into contact with the road surface and the chain tension pressure is constant. .

  An automatic guided vehicle according to a first aspect of the present invention that solves the above-described problem includes an upper frame fixed to a loading platform on which a load material is loaded, a drive unit that is disposed below the upper frame and has drive wheels, and the drive And a lower frame fixed to a portion, and a spring and a coupling mechanism are interposed between the upper frame and the lower frame.

  The automatic guided vehicle according to the second invention for solving the above-described problem is the automatic guided vehicle described in the first invention, wherein the coupling mechanisms are arranged so as to intersect with each other. And a shaft for rotatably fixing the first and second support members, and the first support member is movably engaged with a first upper slot formed in the upper frame on the front side thereof. On the other hand, the rear side is movably locked in a second lower elongated hole formed in the lower frame, and the second support member is moved forward in a first lower elongated hole formed in the lower frame. While being movably locked, the rear side is movably locked to a second upper slot formed in the upper frame.

  An automatic guided vehicle according to a third invention for solving the above-described problem is the automatic guided vehicle described in the second invention, wherein the first upper / lower elongated hole or the second upper / lower elongated hole is provided. One of them is long in the vertical direction, and the other is long in the front-back direction.

  According to the automatic guided vehicle according to the first aspect of the invention, the front and rear horizontal axes that pass through the center of gravity of the automatic guided vehicle are such that the drive wheels travel on the unevenness of the traveling road surface, or the automatic guided vehicle is bent and travels. Even if the center-side swaying (yawing) seen from the front and the swaying in the vertical direction (pitching) that occurs while the automatic guided vehicle is running can be suppressed. As a result, the four caster wheels attached to the loading platform can always be brought into contact with the traveling road surface, and the loading platform can always be kept horizontal. In addition, since the distance between the sprocket attached to the drive wheel and the sprocket that is rotationally driven by the drive motor built in the drive unit is constant, the chain tension pressure can be maintained constant.

  According to the automatic guided vehicle according to the second invention, the same effect as the automatic guided vehicle described in the first invention can be obtained, and the connecting mechanism itself has a simple structure, thereby suppressing an increase in manufacturing cost. can do. Further, by adjusting the sizes of the first and second upper oblong holes and the first and second lower oblong holes, it is possible to adjust the yawing size and the pitching size to be suppressed.

  According to the automatic guided vehicle according to the third invention, the same effect as the automatic guided vehicle described in the second invention is exhibited, and the four caster wheels attached to the loading platform are always grounded to the traveling road surface. It is possible to more reliably maintain the loading platform at a constant level.

  Below, the best form for implementing the automatic guided vehicle concerning the present invention is explained concretely based on an example.

Hereinafter, an automated guided vehicle according to a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a side view of an automatic guided vehicle according to a first embodiment of the present invention, and FIG. 2 is a rear view thereof. FIG. 3 is a rear view of a drive unit included in the automatic guided vehicle according to the first embodiment of the present invention, and FIG. 4 is a side view thereof. FIG. 5 is an enlarged view of the pantograph connection mechanism of the automatic guided vehicle according to the first embodiment of the present invention.

  As shown in FIGS. 1 and 2, the automatic guided vehicle 40 according to the first embodiment of the present invention has a loading platform 1 composed of a pipe frame. A hand handle 2 is fixed to the loading platform 1. A pair of universal caster wheels 3 are attached to the bottom surface of the loading platform 1 on the front side, and a pair of fixed caster wheels 4 are attached to the rear side. Furthermore, a drive unit 10 is disposed at the bottom of the loading platform 1.

  A battery 5, a control unit 6, an operation switch panel 7, and a driving wheel vertical movement device 8 are attached to the hand handle 2.

  As shown in FIGS. 3 and 4, the drive unit 10 includes a pair of drive wheels 11 and a drive unit 12 that drives the drive wheels 11. The drive unit 12 includes two drive motors (not shown). The driving force generated by each driving motor is individually transmitted to the driving wheel 11 through the sprocket 13, the chain 14, and the sprocket 15. A lower frame 16 is fixed to the upper part of the drive unit 12. An upper frame 17 is disposed above the lower frame 16, and the lower frame is constituted by two compression coil springs 18 disposed at a predetermined interval in the front-rear direction and a pantograph coupling mechanism 20 disposed near both sides. 16 and the upper frame 17 are connected. The drive wheels 11 are urged downward by these compression coil springs 18. Note that one end of an outer wire rope 19 is connected to the lower frame 16, and the other end is connected to the drive vertical movement device 8. By pulling one end of the outer wire rope 19 with a lever or the like, the lower frame 16 connected to the other end moves upward, and the drive wheel 11 moves upward so that it does not come into contact with the traveling road surface. .

  As shown in FIG. 5, the upper frame 17 is formed with a first upper long hole 17a that is long in the vertical direction on the front side, and a second upper long hole 17b that is long in the front and rear direction on the rear side. The lower frame 16 is formed with a first lower long hole 16a that is long in the up-down direction on the front side, and a second lower long hole 16b that is long in the front-rear direction on the rear side.

  The pantograph-type connection mechanism 20 includes first and second support members 21 and 22 arranged in an intersecting manner, and a shaft 23 that fixes the first and second support members 21 and 22 to be rotatable at a substantially central position. Have The front side of the first support member 21 is movably locked in the first upper long hole 17a of the upper frame 17 by a bolt 24, and the rear side thereof is inserted in the second lower long hole 16b of the lower frame 16 by a bolt 25. And is movably locked. Similarly to the first support member 21, the front side of the second support member 22 is movably locked in the first lower elongated hole 16 a of the lower frame 16 by a bolt 26, and the rear side of the second support member 22 is secured by a bolt 27. The second upper elongated hole 17b is movably locked.

  In addition, the protrusion that projects downward from the lower frame 16 is a rotation that measures the angle of the axis of the traveling direction of the drive wheels 11 with respect to the loading platform 1 with respect to the horizontal axis that passes through the center of gravity of the automatic guided vehicle 40 A position measuring device (rotational position measuring means) (not shown) is attached. As shown in FIGS. 3 and 4, a bent fixing member 28 is fixed to the front portion of the drive unit 12 by a bolt 29, and an induction sensor that detects the magnetic tape 30 disposed on the fixed road 28 on the traveling road surface. 31 is attached. The guided sensor 31 causes the automatic guided vehicle 40 to travel on the magnetic tape 30 disposed on the traveling road surface.

  Therefore, according to the automatic guided vehicle 40 according to the first embodiment of the present invention, the driving wheel 11 travels on the unevenness of the traveling road surface, or the automatic guided vehicle 40 itself travels in a curved manner, thereby Suppresses left and right swaying (yawing) when viewed from the front centered on the front and rear horizontal axis passing through the center of gravity of the vehicle 40 and vertical swaying (pitching) that occurs while the automated guided vehicle 40 is running. can do. As a result, the four caster wheels attached to the loading platform 1, that is, the free caster wheels 3 and the fixed caster wheels 4 can always be brought into contact with the traveling road surface, and the loading platform 1 can be always kept horizontal. Since the distance between the sprocket 15 attached to the drive wheel 11 and the sprocket 13 that is rotationally driven by the drive motor built in the drive unit 12 is constant, the tension of the chain 14 can be kept constant.

  The pantograph type connecting mechanism 20 itself has a simple structure, and an increase in its manufacturing cost can be suppressed. Also, by adjusting the sizes of the first and second upper elongated holes 17a and 17b and the first and second lower elongated holes 16a and 16b, the yawing and the pitching to be suppressed can be adjusted. Can do.

  In the above description, the first upper and lower elongated holes 17a and 16a formed long in the vertical direction on the front side and the second upper and lower elongated holes 17b and 16b formed long in the front and rear direction on the rear side have been described. A long slot in the vertical direction may be formed on either the front side or the rear side, and a long slot in the front and rear direction may be formed on the other side, and a long slot in the front and back direction may be formed on the front side. On the side, even if a long hole is formed in the vertical direction, the same effects as the first upper / lower elongated holes 17a, 16a and the second upper / lower elongated holes 17b, 16b are obtained.

  The present invention can be used for an automatic guided vehicle, and in particular, can be used for an automatic guided vehicle in which four caster wheels are always brought into contact with a traveling road surface and a cargo bed can be maintained horizontally.

It is a side view of the automatic guided vehicle concerning the 1st example of the present invention. It is a rear view of the automatic guided vehicle concerning the 1st example of the present invention. It is a rear view of the drive unit which the automatic guided vehicle concerning the 1st Example of the present invention has. It is a side view of the drive unit which the automatic guided vehicle concerning the 1st example of the present invention has. It is an enlarged view of the pantograph type connecting mechanism which the automatic guided vehicle concerning the 1st example of the present invention has. It is explanatory drawing of the drive mechanism of the conventional automatic guided vehicle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Loading platform 2 Push handle 3 Swivel caster wheel 4 Fixed caster wheel 5 Battery 6 Control unit 7 Operation switch panel 8 Drive wheel vertical movement apparatus 10 Drive unit 11 Drive wheel 12 Drive part 13 Sprocket 14 Chain 15 Sprocket 16 Lower frame 17 Upper frame 18 Compression coil spring 19 Wire rope 20 with outer pantograph type coupling mechanism 21 First support member 22 Second support member 23 Shafts 24, 25, 26, 27 Bolt 40 Automated guided vehicle

Claims (3)

An upper frame fixed to the loading platform for loading the load material;
A drive unit disposed below the upper frame and having drive wheels;
A lower frame fixed to the drive unit;
The automatic guided vehicle characterized by interposing a spring and a connecting mechanism between the upper frame and the lower frame. The automatic guided vehicle according to claim 1,
The coupling mechanism includes first and second support members arranged to cross each other;
A shaft that rotatably fixes the first and second support members to each other;
The front side of the first support member is movably locked in a first upper slot formed in the upper frame, and the rear side of the first support member is movable in a second lower slot formed in the lower frame. Locked,
The front side of the second support member is movably locked in a first lower slot formed in the lower frame, and the rear side is movable in a second upper slot formed in the upper frame. An automatic guided vehicle that is locked. The automatic guided vehicle according to claim 2,
One of the first upper / lower elongated holes or the second upper / lower elongated holes is formed long in the vertical direction, and the other is formed long in the front / rear direction.

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