Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3889833 A
Publication typeGrant
Publication dateJun 17, 1975
Filing dateSep 21, 1973
Priority dateSep 21, 1973
Publication numberUS 3889833 A, US 3889833A, US-A-3889833, US3889833 A, US3889833A
InventorsThomas Onas Leon
Original AssigneeSouthwire Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Personnel safety platform for forklift
US 3889833 A
Abstract
This disclosure relates to a personnel platform for a forklift having various safety features for the protection of human life. Primarily, the platform includes pivotable locking means adapted to cooperate with the abutting plate of a forklift for releasably securing the platform on the forklift to prevent the platform from sliding off the forks upon tilting thereof. The platform also includes a safety door which will open only inwardly into the platform, and a safety latch carried by the door which prevents the door from opening outwardly. A safety interlock is also provided in the platform which may be connected with the ignition system of a forklift whereby personnel in the platform can control the power operation thereof.
Images(1)
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

[ June 17, 1975 PERSONNEL SAFETY PLATFORM FOR 3,587,893 6/l97l 214/620 FORKLIFT E F k E w Primary .raminer ran erner Inventor. Onas Leon Thomas, Carrollton, Ga. Assistant Examiner Lawrence J- Oresky Assignee: Southwire Company, Carrollton, Attorney, Agent, or Firm-Van C. Wilks; Herbert M.

Ga. Hanegan; Stanley L. Tate Filed: Sept. 21, 1973 A l N '399 485 {57] ABSTRACT This disclosure relates to a personnel platform for a forklift having various safety features for the protec- U.S. 214/620; 214/750 tion of human life. Primarily, the platform includes lnt. 865G 47/00 pivotable locking means adapted to cooperate with Field of Search 182/2, 63, 113', 49/381, the abutting plate of a forklift for releasably securing /620, L 750 the platform on the forklift to prevent the platform from sliding off the forks upon tilting thereof. The References Cited platform also includes a safety door which will open UNITED STATES PATENTS only inwardly into the platform, and a safety latch carried by the door which prevents the door from opening outwardly. A safety the platform which may be connected with the igni- United States Patent Thomas interlock is also provided in tion system of a forklift whereby personnel in the platform can control the power operation thereof.

7 Claims, 2 Drawing Figures Dane.............

968 Calletti et al. Range PERSONNEL SAFETY PLATFORM FOR FORKLIFT This invention relates generally to the field of material handling and personnel transportation, and more particularly to an industrial personnel platform for a forklift having various safety features.

The use of the industrial forklift in various plants, warehouses and the like is well known. The typical forklift is a mobile, generally battery-powered, vehicle having means on the front end thereof for lifting pailets and the like above the ground both for transportation thereof within the plant as well as for movement of the load from one elevation to another. The load handling means usually consists of two tongues or forks which extend outwardly from either side of a vertically extending mast carried on the front of the vehicle, and which are adapted to be received in appropriate means under the pallet or the like for lifting and transporting the pallet above the ground.

In some instances forklifts are used to elevate personnel above the ground for the purpose of operating plant machinery, or for making routine inspections and maintenance procedures. When a forklift is used in this capacity a personnel platform is normally provided so that the personnel being lifted by a forklift will have a reasonable safe platform or compartment in which to work and on which to place their materials and equipment. Such platforms generally have a floor similar to that of the typical load-carrying pallet, but additionally have side walls extending upwardly from the floor to provide a measure of safety to the personnel being carried thereon.

While such typical personnel platforms as heretofore used may have included grooves or channels located beneath the floor through which the forks of the forklift could extend and thus prevent the platform from sliding off the sides of the forks, no means were provided for preventing the platform from sliding axially off of the forks in the event of downward tilting thereof. This, of course, provided a substantial safety hazard to personnel being lifted high above the floor in a plant and resulted in many serious accidents and injuries.

Heretofore, several expedients have been attempted to alleviate the dangers inherent in the tilting of forklift platforms. For example. setscrews were provided in the floor of a platform which extended through in engagement with the forks to provide either a positive lock or a press fit thereagainst. This expedient left much to be desired in that the setscrews were susceptible to shear in the case of a positive lock, and were susceptible to slipping in the case of the press fit. Another approach by the prior art was for a chain to be simply slipped around the mast of the forklift and fastened to suitable means provided on the platform. While the chain was reasonably effective, it represented a haphazard approach to the problem and was many times ignored or forgotten by workmen.

In addition to the safety hazard discussed above, personnel platforms of the prior art also inherently included other safety hazards. One such hazard was provided by access doors in the side walls of the platform which could accidently swing open while the platform was supported high above the ground and thus endanger personnel located therein. Moreover, inasmuch as the operation of prior art platforms was controlled from the forklift located on the ground, personnel located in the platform had no control over the movement thereof and thus could not stop movement, either vertical or transverse, in the event of an emergency condition.

it is, therefore, a primary object of this invention to provide a personnel platform for a forklift which is constructed so as to provide a measure of safety for personnel carried therein.

More particularly, it is an object of this invention to provide a personnel platform for a forklift which includes locking means adapted to cooperate with the abutting plate of a forklift for releasably securing the platform on the forklift to prevent the platform from sliding off the forks upon tilting thereof.

Another object of this invention is to provide a per sonnel platform for a forklift which includes access doors which are prevented from accidentally swinging open.

Yet another object of this invention is to provide a personnel platform for a forklift which includes control means whereby personnel in the platform can control the operation and movement thereof.

Still another object of this invention is to provide a personnel platform for a forklift having various safety features which are simple and easily used, and which are so constructed and arranged so as to invite routine application thereof by personnel using the platform.

Briefly, these and other objects of the invention that may become hereinafter apparent are accomplished in accordance with this invention by constructing a personnel platform having a floor and upstanding side walls, and at least one door providing access into the platform. Latch means are pivotably mounted on at least one ofthe side walls and are adapted to be rotated upwardly in a vertical plane so as to permit the abutting plate of a forklift to be brought up against the side walls, and then rotated downwardly behind the abutting plate in locking engagement therewith so as to prevent the platform from sliding off of the forks of the forklift upon tilting thereof.

The latch means include normally upwardly and downwardly extending portions which are connected by a generally horizontally extending portion to define a somewhat square Z. The generally horizontally extending portion is journalled in hinge means carried on the side wall of the platform, and the downwardly ex tending portion of the latch is constructed of solid rod or the like which is heavier than the upwardly extending portion of the latch which may be constructed of a tubular member such as a pipe section. Consequently, the latch will be biased by gravity to return to its normal position when rotated therefrom such that it will always be in its locking position except when positively rotated therefrom and held in the unlocked position. Normally, two such latch means are provided such that the abutting plate of the forklift, which is brought up against the side of the platform, will be positively engaged on either side of the mast.

The access door of the platform is also provided with a latch which is adapted to cooperate with a portion of one of the side walls of the platform and which prevents the door from opening outwardly from the platform. In this manner accidental outward opening of the door is prevented which provides an added measure of safety to personnel located therein.

Electrical interlock means are also provided on the platform which are adapted to be connected in series with the ignition system of the forklift whereby personnel in the platform can control the operation thereof and stop the forklift in case of emergency.

With the above and other objects in view that may become hereinafter apparent. the nature of the invention may be more clearly understood by reference to the attached drawing. the following detailed description thereof. and the appended claimed subject matter.

lN THE DRAWING FIG. 1 is a perspective view of the personnel platform of this invention supported on a forklift having the mast and other portions thereof cut away. and illustrates the two novel latch means. one ofwhich is in the downward locking position in engagement with the abutting plate of the forklift. and the other being in the upward unlocked position;

FIG. 2 is a fragmentary perspective view of one of the novel latch means of this invention. and has portions thereof cut away for clarity to illustrate that the down wardly extending portion thereof is a solid member and the upwardly extending portion is a tubular member.

Referring now to the drawings in detail there is illus trated in FIG. 1 a personnel platform 10 supported on a forklift [2. The platform 10 includes a floor 14 and upstanding side walls 16.

The forklift 12 includes a body 18, wheels 20. and a mast 22 which carries the vertical power lift linkage (not shown). An abutting plate or carriage 24 is normally carried on the front of the forklift l2 and suitably connected to the power lift linkage contained within the mast 22. Forks (not shown) extend from the lower edge of the abutting plate 24 beneath the floor 14 of the platform 10 and are received within suitable channels (not shown) whereby the platform 10 may be transported and lifted vertically above the ground by i the forklift 12.

As illustrated. the side walls 16 of the platform I are of a frame construction and include corner posts 26, upper and lower horizontal rails 28 and 29. and median horizontal rails 30. Wire mesh 32 of suitable heavy guage may be provided to extend between the lower rails 29 and the median rails 30.

In accordance with this invention. latch means 34 are provided on the platform and are adapted to cooperate with the abutting plate 24 to releasably lock the platform 10 on the forks of the forklift 12. As seen in FIG. 1. two such latch means 34 are mounted on one of the median rails 30 at either end thereof adjacent the corner posts 26. The latching means 34 are suitably journalled in hinges 36 carried by the median rail 30.

As seen most clearly in FIG. 2, the latch means are of generally square Z construction and include a normally downwardly extending portion 38 and a normally upwardly extending portion 40 connected by a gener ally horizontally extending portion 42 which is journalled in the hinge 36. Suitable collars 44 are provided on the horizontal portion 42 to prevent axial sliding thereof in the hinge 36. The normaily downwardly ex tending portion 38 of the latch 34 may be constructed of solid metal rod or the like so that it will be heavier than the generally upwardly extending portion 40 which may be constructed ofa tubular material such as a pipe section. Consequently, the latch 34 will be biased by gravity to return to its normal position as shown in FIG. 2 whenever it is positively rotated therefrom and then released. This will assure that the latch 34 will normally maintain its locked position.

It should be apparent. therefore, that when the forklift l2 is brought up against the personnel platform 10, the latches 34 are rotated upwardly as shown on the right side in FIG. 1 so that the abutting plate 24 may be brought up against the side wall 16 and the forks (not shown) engaged under the floor 14. Thereafter. the latches 34 are released and will return under the force of gravity to their normal position. as seen on the left in FIG. 1. behind the abutting plate 24 in locking engagement therewith. The personnel platform 10 is thus locked on the forklift l2 and is prevented from slipping axially off of the forks in the event of tilting thereof.

An access door 50 having a latch 52 is provided in one of the side walls 16. The door 50 includes a rod 54 that is suitably journalled in hinges 56 carried by the adjacent corner post 26. The latch 52 includes a generally Lshaped extension 58 which is adapted to extend about the inside of a vertical post 60 of the adjacent side wall 16 so as to prevent outward opening of the door 50. Consequently. the door 50 may open only inwardly into the platform 10 thereby providing an additional measure of safety to personnel located therein.

A controi box having a switch 72 is suitably mounted on one of the side walls T6 of the platform 10. A suitable electrical cable 74 extends from the control box 70 and is adapted to be connected to the ignition ofthe forklift [2. The switch 72 is thus connected in series with the forklift ignition and provides a safety interlock whereby operation of the forklift 12 may be con trolled by personnel located within the platform 10.

Other safety equipment. such as a fire extinguisher 76 may be located within the platform 10. Additionally. means may be provided such that a born (not shown) in the forklift 12 may be actuated from a pushbutton located within the platform 10.

hi view of the foregoing, it should be apparent that there is provided in accordance with this invention a novel industrial personnel platform for a forklift having various safety features which render it less hazardous for use than the prior art platforms of this type. The safety features are built into and form a part of the platform and are easily used and accessible to personnel. thereby facilitating their use. The novel latch means are of simple and solid construction and provide few parts that would tend to wear or fail during the use. The disproportionate weight construction 'thereof facilitates a normally positive lock and failsafe protection of both equipment and human life.

Although only a preferred embodiment of the invention has been specifically illustrated and described herein. it is to be understood that other minor modifications thereof could be made without departing front the spirit of the invention.

lt is claimed:

1. A personnel platform for a forklift having lifting forks and an abutting plate. said platform comprising a floor and upstanding side walls. at least one door pro viding access into said platform. means located beneath said floor for receiving the lifting forks of a forklift. locking means secured to at least one of said side walls adapted to cooperate with the abutting plate of a forklift for releasably securing said platform on the forklift to prevent said platform from sliding off of the forks upon tilting thereof. said locking means including at least one latch means pivotably mounted on said at least one side wall and rotatable about an axis extend ing substantially parallel to the longitudinal axes of said forks, said latch means being adapted to be rotated up wardly in a vertical plane so as to permit the abutting plate of a forklift to be brought up against said side wall and then rotated downward behind the abutting plate in locking engagement therewith, and wherein said latch means is normally biased in the locking position thereof.

2. A personnel platform for a forklift having lifting forks and an abutting plate, said platform comprising a floor and upstanding side walls, at least one door providing access into said platform, means located beneath said floor for receiving the lifting forks of a forklift, locking means positioned on at least one of said side walls adapted to cooperate with the abutting plate of a forklift for releasably securing said platform on the forklift to prevent said platform from sliding off of the forks upon tilting thereof, said locking means including at least one latch means pivotably mounted on said at least one side wall and adapted to be rotated upwardly in a vertical plane so as to permit the abutting plate of a forklift to be brought up against said side wall and then rotated downward behind the abutting plate in locking engagement therewith, said latch means including normally upwardly and downwardly extending portions connected by a generally horizontally extending portion, said generally horizontally extending portion being journalled in hinge means, and said downwardly extending portion being heavier than said upwardly extending portion whereby said latch means will be biased by gravity to return to its normal position when rotated therefrom.

3. A personnel platform as defined in claim 2 wherein said normally upwardly extending portion is a tubular member and said normally downwardly extending portion is a solid rod member.

4. A personnel platform as defined in claim 1 and fur ther including means for preventing said at least one door from opening outwardly from said platform.

5. A personnel platform as defined in claim 4 wherein said preventing means includes latch means carried by said at least one door adapted to cooperate with a portion of one of said side walls.

6. A personnel platform as defined in claim 1 and further including interlock means on said platform adapted to be connected with the ignition system of a forklift whereby personnel in said platform can control the movement thereof by the forklift on which it is se cured.

7. A personnel platform as defined in claim 1 wherein said latch means must be rotated through an angle of approximately in order to effect disengagement from the abutting plate of a forklift.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2620930 *Feb 18, 1949Dec 9, 1952Weber Aircraft CorpAdjustable object handling cradle
US2826322 *Apr 30, 1956Mar 11, 1958Posehn William ABarrel lifter attachment for fork lift trucks
US3016973 *Dec 29, 1958Jan 16, 1962Clark Equipment CoLift truck
US3101128 *May 31, 1962Aug 20, 1963Ford Motor CoPersonnel platform for fork lift
US3102307 *Sep 1, 1959Sep 3, 1963Stanley WorksDoor mounting assembly
US3379281 *Mar 8, 1966Apr 23, 1968Standard Structures IncMethod and equipment for building construction
US3415339 *Apr 18, 1967Dec 10, 1968Clyde M. RangeFork lift attachment
US3587893 *Jun 13, 1969Jun 28, 1971Laken VincentMaterial handling attachment for lift truck
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4708576 *Jan 8, 1986Nov 24, 1987Emmett HinesAccessory for expanding the payload capacity of a forklift
US5064338 *Dec 22, 1989Nov 12, 1991Lawrence Inc.Implement mounting apparatus for tractors and mowers
US5096018 *Feb 14, 1991Mar 17, 1992Lifting Technologies, Inc.Method and apparatus for securing a manbasket to a forklift
US5316433 *Feb 21, 1992May 31, 1994Loron, Inc.Low profile push-pull slipsheet handler
US5433493 *Mar 25, 1993Jul 18, 1995Lifting Technologies, Inc.Apparatus for securing a load-carrying implement to a lifting member
US6672823 *Sep 11, 2001Jan 6, 2004Cascade CorporationFork positioner for facilitating replacement of forks on lift trucks
US7008167Oct 28, 2003Mar 7, 2006Cascade CorporationFork positioner for facilitating replacement of forks on lift trucks
US8257008 *Mar 19, 2007Sep 4, 2012Walgreen Co.Warehouse loader
US8376673Nov 16, 2009Feb 19, 2013Gordon KOMARNISKYLoad restraint installation apparatus
US8403618Jul 22, 2005Mar 26, 2013Cascade CorporationLift truck load handler
US8651237 *Jun 7, 2011Feb 18, 2014Richard D PulliamWorker support cage for front end loader bucket
US8764373 *Apr 9, 2007Jul 1, 2014Elwood BatesUtility carryall for utility, skid steer and industrial tractors
US20110305552 *Jun 7, 2011Dec 15, 2011Pulliam Richard DWorker support cage for front end loader bucket
Classifications
U.S. Classification414/607, 414/785, 182/222
International ClassificationB66F9/12
Cooperative ClassificationB66F9/127
European ClassificationB66F9/12F