US 4,061,237 A · Forklift truck

Abstract

Apparatus for storing a mobile forklift truck on top of a raised platform such as a loading dock or the floor of a transport truck, and to an improved forklift truck for use in such apparatus. The apparatus includes a pair of stirrups mounted on top of the raised platform to receive the fork tines of the forklift truck, so that when the tines are lowered far enough, the forklift truck is lifted up until its drive wheel is level with the top of the raised platform. The apparatus also includes a collapsible support arm movable between an out-of-the-way position and an operative position level with the platform top, where the support arm engages the drive wheel of the forklift truck. The improved mobile forklift truck of this invention has a "ready condition" in which it can be brought into position for self-storage on the raised platform, in which condition forwardly extending wheels can move through a restricted "collapsing zone" having specified boundaries into out-of-the-way storage positions. Several embodiments of the improved forklift truck are disclosed, in each of which the upper boundary of the forward portion of the collapsing zone is low enough that the support wheels retracted into out-of-the-way storage positions do not strike any downhanging parts of the raised platform, and the rear boundary of the collapsing zone is far enough forward to avoid any protrusions that would interfere with freedom of movement of the operator behind the forklift truck.

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Drawings

Claims33

Dependent claims

In apparatus for storing a mobile forklift truck on top of a raised platform, such as a loading dock or the platform bed of a conventional motor truck, said forklift truck including a frame assembly comprising a horizontal base member with a vertical frame member mounted thereon, main support wheel means and drive wheel means carried by said frame assembly to move the forklift truck about in use, a fork with a pair of generally horizontal tines mounted on said vertical frame member at the front end thereof, lifting means for raising and lowering said fork tines on said vertical frame member, and drive means for actuating said lifting means to raise and lower said fork selectively, said forklift truck being collapsible from an operative condition in which said main support wheel means projects forward beyond said vertical frame member to a storage condition in which said main support wheel means is located substantially entirely behind the forwardmost portion of said vertical frame member and said tine lifting means, the improvement which comprises:

a pair of stirrups mounted on top of said raised platform adapted to receive said tines, each of said stirrups being spaced from the edge of said platform a distance that is less than the distance to which said tines extend beyond the forwardmost portion of said vertical frame member, said tine lifting means, and said main wheel support means when the forklift truck is in its said collapsed condition;
and
a collapsible support arm mounted on said raised platform movable between an out-of-the-way position and an operative position in which it is substantially level with the top of said platform,
whereby when said fork tines are positioned in said stirrups, said forklift truck is put into its said storage condition, said fork tines are lowered far enough with respect to said vertical frame member that said frame assembly with said drive wheel means is raised to the level of said platform top, and said collapsible support arm is moved into its operative position where it engages the rearmost wheel means carried by said frame assembly, actuating said drive wheel means in contact with one of said support arm and said raised platform will then cause the forklift truck to move forward upon the platform until said tines are fully inserted in their respective stirrups and said forklift truck is positioned entirely within said platform edge.

1 more element

In an improved mobile forklift truck adapted for self-storage on top of the platform bed of a conventional motor truck having a pair of stirrups mounted on top thereof, said forklift truck including a frame assembly comprising a horizontal base member with a vertical frame member mounted thereon, main support wheel means carried by a pair of arms pivotally attached to said frame assembly, and drive wheel means carried by said frame assembly to move the forklift truck about in use, a fork with a pair of generally horizontal tines mounted on said vertical frame member at the front end thereof, lifting means for raising and lowering said fork tines on said vertical frame member, and drive means for actuating said lifting means to raise and lower said fork selectively, said forklift truck being collapsible from an operative condition in which said main support wheel means projects forward beyond said vertical frame member to a storage condition in which said main support wheel means is located in an out-of-the-way position substantially entirely behind the forwardmost portion of said vertical frame and said tine lifting means, the improvement which comprises the feature that:

the axis of rotation of said main support wheel means, when said forklift truck is in its operative condition, is located a distance in front of said vertical frame member that is substantially equal to at least one-half the length of said fork tines,
said forklift truck has a ready condition in which it can be brought into position for self-storage on said truck platform bed and in which condition support wheel means extends forward with the axis of rotation thereof located in front of the forwardmost portion of said vertical frame member, said fork tines being capable of being raised at least as high as the top of the platform bed of said conventional motor truck when the forklift truck is in its said ready condition and is standing upon the ground behind the motor truck,
said support wheel means being movable from said location in front of said vertical frame member through a restricted collapsing zone into an out-of-the-way storage position located substantially entirely forward of the rear end of the forklift truck when it is in its operative condition and substantially entirely behind the forwardmost portion of said vertical frame member and said tine lifting means, without moving any support wheel means into a position forward of said forwardmost portion of said vertical frame member and said tine lifting means, and
said collapsing zone has an upper boundary that is no higher than about 24 inches above the ground in that portion of the zone lying forward of the forwardmost portion of said verticle frame member and said tine lifting means, and a rear boundary that does not extend any substantial distance behind the rear end of said forklift truck when it is in its said operative condition,
whereby when said fork tines are positioned in said stirrups and have been lowered far enough with respect to said vertical frame member to raise the forklift truck in its said ready condition just off the ground, said support wheel means that extend in front of said vertical frame member at that time can be moved through said collapsing zone to bring the forklift truck from its said ready condition to its said collapsed storage condition.

2 more elements

In an improved mobile forklift truck adapted for self-storage on top of the platform bed of a conventional motor truck having a pair of stirrups mounted on top thereof, said forklift truck including a frame assembly comprising a horizontal base member with a vertical frame member mounted thereon, main support wheel means carried by a pair of arms pivotally attached to said frame assembly, and drive wheel means carried by said frame assembly to move the forklift truck about in use, a fork with a pair of generally horizontal tines mounted on said vertical frame member at the front end thereof, lifting means for raising and lowering said fork tines on said vertical frame member, and drive means for actuating said lifting means to raise and lower said fork selectively, said forklift truck being collapsible from an operative condition in which said main support wheel means projects forward beyond said vertical frame member to a storage condition in which said main support wheel means is located in an out-of-the-way position substantially entirely behind the forwardmost portion of said vertical frame member and said tine lifting means, the improvement which comprises the feature that:

the axis of rotation of said main support wheel means, when said forklift truck is in its operative condition, is located a distance in front of said vertical frame member that is substantially equal to at least one-half the length of said fork tines,
said forklift truck has a ready condition in which it can be brought into position for self-storage on said truck platform bed and in which condition said main support wheel means extends forward with the axis of rotation thereof located in front of the forwardmost portion of said vertical frame member, said fork tines being capable of being raised at least as high as the top of the platform bed of said conventional motor truck when the forklift truck is in its said ready condition and is standing upon the ground behind the motor truck,
said forwardly extending main support wheel means being movable from said location in front of said vertical frame member through a restricted collapsing zone into an out-of-the-way storage position located substantially entirely forward of the rear end of the forklift truck when it is in its operative condition and substantially entirely behind the forwardmost portion of said vertical frame member and said tine lifting means, without moving any support wheel means into a position forward of said forwardmost portion of said vertical frame member and said tine lifting means, and
said collapsing zone has an upper boundary that is no higher than about 24 inches above the ground in that portion of the zone lying forward of the forwardmost portion of said vertical frame member and said tine lifting means, and a rear boundary that does not extend any substantial distance behind the rear end of said forklift truck when it is in its said operative condition,
whereby when said fork tines are positioned in said stirrups and have been lowered far enough with respect to said vertical frame member to raise the forklift truck in its said ready condition just off the ground, said main support wheel means that extend in front of said vertical frame member at that time can be moved through said collapsing zone to bring the forklift truck from its said ready condition to its said collapsed storage condition.

2 more elements

An improved mobile forklift truck adapted for self-storage on top of a raised platform, such as a loading dock or the platform bed of a conventional motor truck, having a pair of stirrups mounted on top thereof, said forklift truck including a frame assembly comprising a horizontal base member with a vertical frame member mounted thereon, main support wheel means and drive wheel means carried by said frame assembly to move the forklift truck about in use, said main support wheel means being carried respectively by a pair of arms pivotally attached to said frame assembly, a fork with a pair of generally horizontal tines mounted on said vertical frame member at the front end thereof, lifting means for raising and lowering said fork tines on said vertical frame member, and drive means for actuating said lifting means to raise and lower said fork selectively, said forklift truck being collapsible from an operative condition in which said main support wheel means projects forward beyond said vertical frame member to a storage condition in which said main support wheel means is located in an out-of-the-way position substantially entirely behind the forwardmost portion of said vertical frame member and said tine lifting means, said fork in its lowest position being lower than every other portion of said forklift truck in its said operative condition, in which the distance from the rear end of said forklift truck to the forwardmost portion of said frame assembly, said tine lifting means, and said main support wheel means when the forklift truck is in its said collapsed storage condition is less than the length of said fork tines, and which includes retractable auxiliary support wheel means, mounted on arms carried by said frame assembly, to support the forklift truck in a ready condition when said main support wheels have been moved into their out-of-the-way storage positions, each of said auxiliary support wheel arms being shorter than said main support wheel arms and being slidably secured in a sleeve member fixedly attached to one of said pivotable main support wheel arms, said sleeve extending at an angle to said main support wheel arm of less than 90.degree. and being attahced thereto at the end thereof opposite the support wheel carried thereby, so that when said tine is in its lowest position said main support wheel arm can be swung up into its out-of-the-way storage position, and said sleeve member is at the same time automatically swung down into a position in which said forklift truck can be put into said ready condition by sliding said auxiliary support wheel arm through said sleeve to bring the auxiliary support wheel carried thereby into a support position for said frame assembly.

In apparatus for storing a mobile forklift truck on top of a raised platform, such as a loading dock or the platform bed of a conventional motor truck, said forklift truck including a frame assembly comprising a horizontal base member with a vertical frame member mounted thereon, main support wheels carried by arms pivotally mounted on said frame assembly and drive wheel means carried by said frame assembly to move the forklift truck about in use, a fork with a pair of generally horizontal tines mounted on said vertical frame member at the front end thereof, lifting means for raising and lowering said fork tines on said vertical frame member, and drive means for actuating said lifting means to raise and lower said fork selectively, said forklift truck being collapsible from an operative condition in which said main support wheel means projects forward beyond said vertical frame member to a storage condition in which said main support wheel means is located substantially entirely behind the forwardmost portion of said vertical frame member and said tine lifting means, said fork in its lowest position being lower than evey other portion of said forklift truck in its said operative condition, the improvement which comprises:

a pair of stirrups mounted on top of said raised platform adapted to receive said tines, each of said stirrups being spaced from the edge of said platform a distance that is less than the distance to which said tines extend beyond the forwardmost portion of said vertical frame member, said tine lifting means, and said first wheel support means when the forklift truck is in its said collapsed condition;
and
a collapsible support arm mounted on said raised platform movable between an out-of-the-way position and an operative position in which it is substantially level with said platform top,
the distance from the rear end of said forklift truck to the forwardmost portion of said frame assembly, said tine lifting means, and said main support wheel means when the forklift truck is in its said collapsed storage condition being less than the length of said fork tines, and
said forklift truck including retractable auxiliary wheels each of which is carried by an arm pivotally attached to said frame assembly to support the truck in a ready condition when said main support wheels have been moved into their out-of-the-way storage positions, each of said auxiliary support wheel arms being shorter than said main support wheel means and being slidably secured in a sleeve member fixedly attached to one of said pivotable main support wheel arms, said sleeve extending at an angle to said main support wheel arm of less than 90.degree. and being attached thereto at the end thereof opposite the support wheel carried thereby, said auxiliary support wheel means being movable into an out-of-the-way storage position in which its forwardmost portion lies substantially entirely behind the forwardmost portion of said vertical frame member, said tine lifting means, and said main support wheel means when the forklift truck is in its said storage condition,
whereby when said fork tines are positioned in said stirrups with the forklift truck in its ready condition, said fork tines are lowered far enough with respect to said vertical frame member that said frame assembly with said drive means is raised to the level of said platform top, and said collapsible support arm is moved into its operative position where it engages the rearmost wheel means carried by said frame assembly, actuating said drive wheel means while it is in contact with one of said support arms and said raised platform will then cause the forklift truck to move forward upon the platform until said tines are fully inserted in their respective stirrups and said forklift truck is positioned entirely within said platform edge.

3 more elements

A method for storing a mobile forklift truck on top of a raised platform, such as a loading dock or the platform bed of a conventional motor truck, having a pair of stirrups mounted on top thereof, said forklift truck including a frame assembly comprising a horizontal base member with a vertical frame member mounted thereon, main support wheel means and drive wheel means carried by said frame assembly to move the forklift truck about in use, a fork with a pair of generally horizontal tines mounted on said vertical frame member at the front end thereof, said tines being adapted to be inserted in said stirrups, lifting means for raising and lowering said fork tines on said vertical frame member, and drive means for actuating said lifting means to raise and lower said fork selectively, said forklift truck being collapsible from an operative condition in which said main support wheel means projects forward beyond said vertical frame member to a storage condition in which said main support wheel means is located substantially entirely behind the forwardmost portion of said vertical frame member and said tine lifting means, the distance said tines extend beyond the forwardmost portion of said vertical frame member, said tine lifting means, and said main wheel support means when the forklift truck is in its said collapsed condition being greater than the distance said stirrups are spaced from the edge of said platform, which comprises:

inserting said tines in their respective stirrups on top of said platform;
lowering the tines with respect to said frame assembly to raise the latter, along with said drive wheel means, substantially to the level of the top of said platform;
collapsing the forklift truck into its storage condition after said fork tines have been lowered far enough to raise the forklift truck off the ground;
engaging the rearmost wheel means carried by said frame assembly with support means attached to said platform after said frame assembly and its associated drive wheel means have been raised substantially to the level of the platform top;
and
actuating said drive wheel means while it is in contact with one of said support means and said raised platform,
whereby the forklift truck is caused to move forward upon the platform until said tines are fully inserted in their respective stirrups and said forklift truck is positioned entirely within said platform edge.

4 more elements

Dependencies are inferred from the claim text.

Description8,165 words

Summary1,439 words

#This invention relates to apparatus for storing a mobile forklift truck on top of a raised platform such as a loading dock or the floor of a transport truck, and to an improved forklift truck for use in such apparatus.

#Forklift trucks are known that can be carried around by a transport truck after they have pulled themselves up underneath the truck and have been secured to the bottom of the exterior of the truck for travel. These prior art forklift trucks are able to raise themselves up under the bed of a transport truck when the tines of the fork have been raised into an elevated position and are then secured in one way or another beneath the truck bed, after which the hydraulic drive of the forklift truck is reversed so that the fork presses downward instead of upward. The result is that the main body of the forklift truck rises, because of the downwardly directed force of the fork, until the forklift truck reaches the level where it is to be stored.

#Forklift trucks of the type just described are disclosed in the patents to Joosten No. U.S. Pat. 3,710,965 and Grether et al. No. 3,799,379. As will be seen from FIG. 6 of the Joosten patent and FIGS. 8 and 12 of the Grether et al. patent, when these forklift trucks are in their storage position they extend backward from the rear end of the transport truck. As a result, they add an awkward length to the transport truck under which they are stored. In addition, they are exposed to the elements during bad weather, as well as to possible damage from collisions with another vehicle or a fixed structure such as a garage wall.

Brief description of the drawings18 figures

#The invention will now be described by reference to the accompanying drawings, in which:

#FIG. 1 is a side elevation of one embodiment of the improved forklift truck of this invention, with the forklift truck in its operative condition and the fork times near the lower end of their range of travel;

#FIG. 2 is a rear elevation of the forklift truck of FIG. 1 in is ready condition, with the main support wheels raised into out-of-the-way storage positions and the auxiliary support wheels extended forward into their support positions;

Detailed description5,975 words

#The various embodiments of the invention disclosed in the accompanying drawing will now be described in more detail.

#Collapsible forklift truck, FIG. 1 is a side elevation view of a mobile forklift truck that can be used with the apparatus of this invention. As there shown, forklift truck 20 includes frame assembly 22 comprising horizontal base member 24 and vertical frame member 26 extending upward therefrom. A pair of main support wheels 28 extends towards the front of forklift truck 20, each of the wheels being carried by an arm 30, rectangular in cross-section and pivotally mounted on an axle 32 carried by vertical frame member 26. Each arm 30 is maintained in its operative position by the engagement of removable leg position pin 34 with a hole suitably located in axle 32. The arm is laterally adjustable in a manner to be explained below (by reference to the fragmentary front elevation of forklift truck 20 in FIG. 2) in the further description of the improved forklift truck of this invention.

#At the rear of forklift truck 20, hydraulic drive wheel 36 is rotatably mounted in carriage 38, which pivots in bracket 40 attached to vertical frame member 26, to permit forklift truck 20 to be steered as it is moved about in use. Steering lever 42 is connected to pivot post 44 to permit the operator of the forklift truck to guide the truck as it is moved along ground 46. Steering lever 42 may occupy any of several positions selected by the operator of forklift truck 20, as indicated in FIG. 7 of the drawing.

Forklift truck

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Forklift truck

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Life of this patent

Abstract

Drawings

Drawings

Claims33

Description8,165 words

Drawings

Classification2 codes

Life of this patent

Description8,165 words