GB2359291A

GB2359291A - Laser alignment apparatus for aligning a fork with a fit-in groove

Info

Publication number: GB2359291A
Application number: GB0101087A
Authority: GB
Inventors: Hiroshi Matsuoi
Original assignee: Nippon Yusoki Co Ltd
Current assignee: Nippon Yusoki Co Ltd
Priority date: 2000-02-10
Filing date: 2001-01-16
Publication date: 2001-08-22
Also published as: FR2804947B1; FR2804947A1; DE10105295A1; JP2001226092A; GB0101087D0

Abstract

A fork lift 1 according to the invention is provided with a row of forks 2, the fork lift having a laser beam irradiation apparatus 8 disposed so as to irradiate a laser beam 9 to a predetermined position which is below the fork 2a and is related to the position thereof. Then, the laser beam irradiation apparatus 8 includes an apparatus for irradiating a laser beam 9 into a fork fit-in groove 3a formed in an upper side of a pallet 3, an apparatus for irradiating the laser beam 9 outside the fork fit-in groove 3a formed in the pallet 3, and an apparatus for irradiating the laser beam 9 inside and outside the fork fit-in groove 3a formed in the upper side of the pallet 3, when the fork 2a is positioned above the fork fit-in groove 3a formed in the upper side of the pallet 3.

Description

2359291 FORK LIFT

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a fork lift comprising a row of forks and more particularly to a construction for facilitating the visibility by an operator of a fork lift of a fork fit-in groove in a pallet when shifting luggage on a row of forks of the fork lift to the pallet.

2. Description of the Related Art

In recent years, articles such as vegetable and clothes are packed up in a cardboard box for carriage and work for carrying such cardboard boxes has been increasing, and although not shown, in carrying such luggage, there may be a case where a fork lift is used which is provided with a number of forks disposed in parallel so as to be spaced away from each other or a so-called row of forks.

Namely, with the row of forks, a plurality of pieces of luggage can be directly received and supported thereon all together which are laid in parallel and stacked in stages, and when driving a fork lift carrying such luggage on its row of f orks, the operator visually aligns f ork f it-in grooves f ormed in an upper side of a pallet prepared in advance for receiving shifted luggage with correspond ing forks which comprise the row of forks, respectively and then shifts the luggage on the 1 row of forks onto the pallet.

However, in order to carry luggage in a stable fashion without causing much deformation of the luggage in carrying out such a shifting operation, it is desirable that the width of the respective forks is broad, and in order to support the shifted and loaded luggage in a stable fashion, it is desirable that the luggage receiving area of the pallet is secured as wide as possible by narrowing the width of the f ork f it-in grooves If such constructions are adopted both for the forks and fork fit-ingrooves, since the gaps between the respective fork f itin grooves and forks become narrower, it is difficult to align the fork fit-in grooves with the forks constituting the row of forks, respectively.

SUMMARY OF THE INVENTION

The present invention was made in view of the aforesaid drawback, and an object thereof is to provide a fork lift which can facilitate the alignment of fork fit-in grooves with a row of forks for shifting luggage.

According to the invention, there is provided a fork lift provided with a row of forks, the fork lift comprising a laser beam irradiation apparatus for irradiating a laser beam to a predetermined position which is below the fork and is related to the position of the fork. According to a second aspect of the invention, there is provided a fork lift, wherein the laser beam irradiation apparatus is disposed such that when the forks are positioned above fork fit-in grooves formed in an upper side of a pallet, a laser beam is irradiated into the fork f it-in groove.

According to the invention, there is provided a f ork lif t, wherein the laser beam irradiation apparatus is disposed such that when the forks are positioned above fork fit-in grooves formed in an upper side of a pallet, a laser beam is irradiated onto the upper side of the pallet outside the f ork f it-in groove. According to a fourth aspect of the invention, there is provided a fork lift as set forth in the first aspect of the invention, wherein the laser beam irradiation apparatus is disposed such that when the forks are positioned above fork fit-in grooves formed in an upper side of a pallet, laser beams are irradiated into and outside the fork fit-in groove.

According to, there is provided a fork lift, wherein the laser beam irradiation apparatus is attached to a lift bracket supporting the forks.

According to the invention, there is provided a fork lif t, wherein the laser beam irradiation apparatus is attached to at least one of the forks.

According to the invention, there is provided a f ork lif t, wherein the laser beam irradiation apparatus is disposed transversely on both sides of the fork. According to an eighth aspect of the invention, there is provided a fork lift as set 3 forth in any of the first to seventh aspects of the invention, wherein the laser beam is irradiated in a direction matching with a longitudinal direction of the fork in a linearized or belt-like state.

According to the invention, there is provided a forklift, wherein the laser beam is irradiated in a direction intersecting with a longitudinal direction of the fork in a linearlized or belt-like state. According to a tenth aspect of the invention, there is provided a fork lift as set forth in any of the first to seventh aspects of the invention, wherein the laser beam is irradiated in a dotted state.

According to the aforesaid constructions, even.if he or she is seated in the driver's seat, the operator of the fork lif t can easily visualize the destination of an irradiated laser beam on the upper side of the pallet, whereby the fork fit-in groove can easily be visualized. Owing to this, even if the gaps of the respective f ork f it-in grooves and f orks are narrow since the fork fit-in groove can easily be visualized, there is secured an advantage that the alignment between the fork fit-in grooves and the row of forks can be facilitated.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a side view schematically showing the overall construction of a fork lift according to the invention.

Fig. 2 is a perspective view showing a relative positional relationship between a row of forks and a pallet, which shows a case where a single laser beam is irradiated in a direction matching with a longitudinal direction of a fork in a long linearized state.

Fig. 3 is a plan view typically showing a case where a single laser beam is irradiated in a direction matching with a longitudinal direction of a fork in a short linearized state.

Fig. 4 is a plan view typically showing a case where a single laser beam is irradiated in a direction matching with a longitudinal direction of a fork in a long belt-like state.

Fig. 5 is a plan view typically showing a case where a single laser beam is irradiated in a direction matching with a longitudinal direction of a fork in a short belt-like state.

Fig. 6 is a plan view typically showing a case where two laser beams are irradiated in a direction matching with a longitudinal direction of a fork in a long linearized state.

Fig. 7 is a plan view typically showing a case where two laser beams are irradiated in a direction matching with a longitudinal direction of a fork in a short linearized state.

Fig. 8 is a plan view typically showing a case where two laser beams are irradiated outside a fork fit-in groove.

Fig. 9 is a plan view typically showing a case where three laser beams are irradiated inside and outside a fork fit-in groove.

Fig. 10 is a plan view showing a case where a laser beam - is irradiated in a direction intersecting with a longitudinal direction of a fork in a linearized or belt-like state.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

Referring to the drawings, embodiments of the invention will be described below.

Fig. 1 is a side view schematically showing an overall construction of a fork lift according to the invention, Fig. 2 is a perspective view showing a relative positional relationship between a row of forks and a pallet, and Figs. 3 to 10 are plan views showing, respectively, typical states in which a laser beam or laser beams are irradiated. In these figures, reference numeral 1 denotes a fork lift, reference numeral 2 a row of forks, and reference numeral 3 a pallet.

Then, here, Fig. 2 shows a case where a single laser beam is irradiated in a direction matching with a longitudinal direction of a fork in a long linearized state, Fig. 3 shows a case where a single laser beam is irradiated in a direction matching with a longitudinal direction of a fork in a short linearized state, Fig. 4 shows a case where a single laser beam is irradiated in a direction matching with a longitudinal direction of a fork in a long beltlike state, and Fig. 5 shows a case where a single laser beam is irradiated in a direction matching with a longitudinal direction of a fork in a short belt-like state.

6 - Additionally, Fig. 6 shows a case where there are provided two laser beams which are irradiated in a direction matching with a longitudinal direction of a fork in a long linearized state, Fig. 7 shows a case where there are provided two laser beams which are irradiated in a direction matching with a longitudinal direction of a fork in a short linearized state, and Fig. 8 shows a case where there are provided two laser beams which are irradiated outside a fork fitin groove. Furthermore, Fig. 9 shows a case where there are provided three laser beams which are irradiated inside and outside a fork fit-in groove, and Fig. 10 shows a case where a single laser beam is irradiated in a direction intersecting with a longitudinal direction of a fork in a linearized state.

As shown in Figs. 1 and 2, the fork lift 1 according to the embodiment of the invention is provided with a row of forks 2 comprising six forks 2a which are disposed in parallel so as to be spaced away from each other, and a lift bracket 5 is constructed so as to vertically move along masts 7 provided to erect at a frontal side of a vehicle body 6 which lift bracket supports the row of forks 2 on which a plurality of pieces of luggage 4 are loaded in such a manner that they are laid side by side and stacked in two stages. Note that in this embodiment, the number of f orks 2a used is six, but the invention is not limited to six with respect to the number of forks and that needless to say, the row of forks 2 may be constituted by any number of forks 2a as long as they are equal to or more than two.

Then, a single laser irradiation apparatus 8 is attached to a lower end portion of the lift bracket 5 corresponding to a lower proximal end portion of one of the six forks 2a constituting the row of forks 2 which is positioned inwardly. As shown in Fig. 2, a laser beam 9 is irradiated downwardly f rom this laser irradiation apparatus 8 in a direction matching with a longitudinal direction of the fork 2a in a long linearized state. Note that as typically shown in Fig. 3, there may be a case where the irradiation of the laser beam 9 is adjusted such that the laser beam is irradiated in a short linearized state, and there is caused no problem even if the laser beam 9 is irradiated in the short linearized state. Additionally, as typically shown in Figs. 4 and 5, the laser beam 9 may, of course, be irradiated in long and short belt-like states.

The luggage 4 loaded on the row of f orks 2 provided on the fork lift 1 is to be carried to the pallet 3 prepared in advance for receiving luggage to be shifted thereto so as to be shifted to and loaded on the pallet 3. Then, when shifting luggage, the driver of the fork lift is required to visually align respective fork fit-in grooves 3a formed in an upper side of the pallet 3 with the forks 2a corresponding thereto which constitutes the row of f orks 2, while being seated in the driver' s seat positioned behind the masts 7.

8 - In carrying out the alignment of the fork fit-in grooves with the corresponding forks, a laser beam 9 is irradiated from the laser beam irradiation apparatus 8 disposed at the lower end portion of the lift bracket 5, and the laser beam 9 so irradiated reaches the upper side of the pallet 3. Thus, even if the environment is dim, the driver of the fork lift can visualize the laser beam 9 irradiated from the laser beam irradiation apparatus 8 while being seated in the driver's seat, whereby the driver can confirm easily visually whether the laser beam 9 reaches within a range with respect to a width direction of the f ork f it-in groove 3a positioned correspondingly thereto, or the laser beam 9 is directed within the fork fit-in groove 3a.

Namely, when carrying out the alignment of the fork f it-grooves and the corresponding forks, the driver moves the row of forks 2 in a direction in which the forks 2a are arranged in parallel until the laser beam 9 reaches within the fork f it-in groove 3a, or does socalled side shifting, and then when he or she visually confirms that the laser beam 9 reaches within the fork fitin groove 3a, the driver determines that the alignment between the respective fork fitin grooves 3a and the respective forks 2a constituting the row of forks 2 has been completed. Thereafter, the driver, who determines that the alignment has been completed, lowers the lift bracket 5 supporting the row off orks 2 along themasts 7, and the respective forks 2a constituting the row of forks 2 fit in the respective f ork f it- in grooves 3a corresponding thereto, and in association with this, the luggage 4 is shifted to and loaded on the upper side of the pallet 3.

Although not shown, it should be noted that in carrying out the alignment, particularly when a laser beam having a long irradiation length is irradiated fromthe laser beam irradiation apparatus 8, as long as the fork lift approaches the pallet diagonally relative to the longitudinal direction of the fork f it-in groove 3a, the driver can easily recognize that the forks 2a are approaching diagonally relative to the forkfitingrooves 3a based on the irradiated state of the laser beam 9 reaching the upper side of the pallet 3. Then, the driver, who has now recognized the situation, can direct the forks 2a straight to the fork f it-in grooves 3a after changing the running direction of the fork lift. Thus, it is preferable that the length of a laser beam 9 irradiated from the laser irradiation apparatus 8 is long.

In the embodiments of the invention, although the laser beam irradiation apparatus 8 is attached to the lift bracket 5, the laser beam irradiation apparatus 8 may be attached directly to the lower proximal end portion of the fork 2a, in other words, a position of the fork 2a near where the horizontal portion and the vertical portion of the fork 2a intersect with each other. Additionally, when this occurs, the attachment of the laser beam irradiation apparatus 8 is not limited to a single fork 2a out of the six ones, and, for example, needless to say, the laser beam irradiation apparatus 8 may be attached to the other fork 2a disposed on the other outermost position of the row of f orks which are arranged in parallel or to a plurality of forks 2a of the six. Additionally, on top of the lift bracket 5 and the lower proximal portion of the fork 2a, the laser beam irradiation apparatus 8 may be attached to any other position on the fork 2a, to be specific, any position which interferes with loading luggage and does not come into contact with the ground, the mast or the vehicle body (portions excluding a mast device).

With respect to the attachment position of the laser beam irradiation apparatus 8, in any of the aforesaid cases, the apparatus should be disposed at a position where the laser beam 9 is allowed to be irradiated to a predetermined position which is lower the fork 2a and is related to the position thereof. The laser beam 9 that is irradiated below the fork 2a includes a laser beam irradiated in a vertical direction from the laser irradiation apparatus 8, a laser beam irradiated so as to be deflected in a direction along the longitudinal direction of the horizontal portion of the fork 2a and a laser beam irradiated so as to be deflected in a direction along the width direction of the fork 2a. In addition, the laser beam that is irradiated to the predetermined position related to the position of the fork 2a includes a l as er beam which has a determined destination for irradiation thereof in accordance with the position of the fork 2a and which informs of the relative position of the fork 2a with respect to a target of irradiation of the laser beam through irradiation thereof More particularly, the presence (the relative position) of the fork 2a above the fork fit-in groove 3a (the target for irradiation) in the pallet 3 can be let known by irradiating the laser beam into the fork fit-in groove. In another specific example, the presence (the relative position) of the fork 2a above the fork fit-in groove 3a (the target for irradiation) in the pallet 3 can be let known by irradiating the laser beam outside the fork fit-in groove 3a. Moreover, in a further specific example, the presence (the relative position) of the fork 2a above the fork fit-in groove 3a (the target for irradiation) in the pallet 3 can be let known by irradiating the laser beam inside and outside the f ork f itin groove 3a.

Furthermore, although not shown, the laser beam irradiation apparatus 8 may be disposed transversely on both sides of a single or a plurality of forks 2a, respectively, and with a construction like this, as typically shown in Fig. 6, since laser beams are irradiated from two laser beam irradiation apparatuses 8 transversely disposed on the both sides of the fork 2a, there is provided an advantage that the widthwise range of the fork fit-in groove 3a can assuredly be 12 visualized by the two laser beams 9. Alternatively, as typically shown in Fig. 8, in embodying this construction, the laser beams 9 irradiated from the two laser beam irradiation apparatuses 8 may be constructed so as to reach outside the fork fit-in groove 3a in the upper side of the pallet 3, and even with a construction like this, the widthwise range of the fork fit-in groove 3a can assuredly be visualized.

Moreover, in the embodiments of the invention, the laser beam 9 is irradiated from the laser beam irradiation apparatus 8 in the direction matching with the longitudinal direction of the fork 2a in the linearized or belt-like state, but, as typically shown. in Fig. 10, the laser beam irradiated in the lineari1zed or belt-like state may be directed in a direction intersecting with the longitudinal direction of the fork 2a, and needless to say, the laser beam so irradiated maybe directed, for example, in a direction intersecting at right angles with the longitudinal direction of the fork 2a. With this direction of irradiation, the widthwise range of the fork fit-in groove 3a can be visualized with a single laser beam 9. Moreover, the laser beam 9 is not necessarily irradiated in the linearized or belt-like state, and although not shown, needless to say, the laser beam 9 may be irradiated in a dot-like state.

As has been described heretofore, according to the fork lift of the invention, with the provision of the laser beam irradiation apparatus or apparatuses for irradiating a laser 13 - beam or laser beams to a predetermined position or positions which are below the fork or forks and are related to the position or positions thereof, in the first example, the presence of the fork above the fork fitin groove formed in the upper side' of the pallet can be let known through the irradiation of the laser beam within the f ork f it-in groove, in the second example, the presence of the fork above the fork fit-in groove formed in the upper side of the pallet can be let known through the irradiation of the laser beam outside the fork fit-in groove, and in the third example, and the presence of the fork above the fork fit-in groove formed in the upper side of the pallet can be let known through the irradiation of the laser beam inside and outside the fork fit-in groove, whereby the operator can easily perf orm the alignment of the f orks with the f ork f it-in grooves f ormed in the pallet. Owing to this, even in a case where the gaps of the respective fork fit-in grooves and forks are narrow, which is specific with the row of forks and the pallet for exclusive use with a row of forks, the alignment of the forks with the fork fit-in grooves can be carried out easily and assuredly, whereby not only can the operator perform loading work without feeling any stress, but also the time required for the alignment of the forks with the fork fit-in grooves can be reduced, whereby the overall time of loading operation can in turn be reduced.

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Claims

CLAIMS:

1. A fork lift comprising:

fork; and laser beam irradiation apparatus for irradiating a laser beam to a predetermined position which is below the fork and is related to the position of the fork.

2. The fork lift as set forth in claim 1 wherein the laser beam irradiation apparatus is disposed to irradiate the laser beam into a fork fit-in groove formed in an upper side of a pallet,when the fork is positioned above the fork fit-in groove of the pallet.

3. The fork lift as set forth in claim 1 wherein the laser beam irradiation apparatus is disposed to irradiate the laser beam onto an upper side of a pallet and outside of a fork f it-in groove formed in the pallet, when the fork is positioned above the fork fit-in groove.

4. The fork lift as set forth in claim 1 wherein the laser beam irradiation apparatus is disposed to irradiate the laser beam into and outside of a fork fit-in groove formed in an upper side of a pallet, when the fork is positioned above the fork fit-in groove.

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5. The fork lift as set forth in any of claims 1 to 4 further comprising a lift bracket supportin the fork, wherein the laser beam irradiation apparatus is attached to the lift bracket.

6. The fork lift as set forth in any of claims 1 to 4, wherein the laser beam irradiation apparatus is attached to the fork.

7. The fork lift as set forth in any of claims 1 to 4 wherein the laser beam irradiation apparatus comprising two laser beam irradiation apparatuses transversely disposed on both sides of the fork.

8. The fork lift as set forth in any of claims 1 to 7 wherein the laser beam is irradiated in a direction matching with a longitudinal direction of the fork in a linearized or belt-like state.

9. The fork lift as set forth in any of claims 1 to 7 wherein the laser beam is irradiated in a direction intersecting with a longitudinal direction of the fork in a linearlized or belt-like state.

10. The fork lift as sf,-t forth in any of claims 1 to 16 7 wherein the laser beam is irradiated in a dotted state.

11. The fork lift as set forth in any one of claims 1 to 10 wherein the fork comprising a plurality of branches arranged in parallel to each other.

12. A fork lift substantially as hereinbefore described with reference to any one of the accompanying drawings.

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