Patent Application
20080107511
I. Field of the Invention
This invention relates generally to material handling tools, and more particularly to a tool for grasping and dragging wooden shipping pallets along a floor surface.
II. Discussion of the Prior Art
In shipping and receiving departments of factories, warehouses and retail establishments, products are often contained on wooden pallets so that a forklift machine can readily pick up and transport the pallet and products from one point to another. Another well-known machine for manipulating pallets is the so-called “pallet-jack”. The pallet-jack machine rides on wheels and has a pair of tines or forks that are spaced apart by a distance dictated by the dimensions of the pallet to be carried. An elongated handle can be pumped up-and-down to hydraulically or otherwise elevate the forks and raise a pallet from the floor so that the pallet-jack can be easily pulled. The Fahnestock U.S. Pat. No. 1,115,796 is an example of this type of tool.
It is frequently necessary to reposition empty pallets in warehouses or factories, say, in moving them from a receiving department to the production floor or merely moving them to and from an empty pallet storage area in the building. While a forklift or pallet-jack could be used, such machines are relatively costly and should be used for moving loaded pallets or stacks thereof rather than moving an empty pallet one at a time.
Thus, a need exists for a relatively low cost tool that can be used to pull individual, unloaded wooden pallets from one point to another in an industrial or retail setting. The tool should be of a type that makes it unnecessary for a laborer to manually pick up and carry a wooden pallet that may typically weigh 50 lbs. or more and is somewhat unwieldy in shape. The present invention is just such a tool.
In accordance with the present invention, there is provided a tool for grasping and pulling articles, such as wooden pallets. The tool includes a base member that is supported from the ground by a pair of wheels. An elongated handle having first and second ends, the first end being connected to the base plate and a second end that connects to a grip member that extends transversely to the longitudinal axis of the handle. Coupled to the base member is a pair of jaw members, each having first and second end portions. The pair of jaw members is pivotally joined to one another at a location that is offset from the first and second end portions. More particularly, the pair of jaw members is coupled to the base member through first and second linkages that are pivotally coupled at a first end to the base member. The first linkage is pivotally coupled at its second end to the second end portion of one of the pair of jaw members. The second linkage is pivotally coupled at its second end to the second end portion of the other of the pair of jaw members. A tension spring extends between the second end portions of the pair of jaw members to urge the first end portions of the two jaw members toward one another. An elongated, flexible member, such as a cable, cord or wire, extends along the length of the handle from the grip member to the location offset from the first and second ends where the jaw members are pivotally joined to one another. A tension force applied to the elongated flexible member acts to stretch the spring and causes the first end portions of the jaw members to separate relative to one another. The first end portions of the jaw members can then be placed about a main stringer of the pallet to be moved and when the tension on the elongated flexible member is released, the spring will urge the first end portions of the jaw members firmly against the wooden stringer so that now when the handle is pulled, the wheeled tool will drag the pallet with it. The linkages are arranged such that the pulling force applied to the handle causes the jaws to more firmly grip the pallet stringer.
The foregoing features, objects and advantages of the invention will become apparent to those skilled in the art from the following details description of a preferred embodiment especially when considered in conjunction with the accompanying drawings in which:
Certain terminology will be used in the following description for convenience in reference only and will not be limiting. The words “upwardly”, “downwardly”, “rightwardly” and “leftwardly” will refer to directions in the drawings to which reference is made. The words “inwardly” and “outwardly” will refer to directions toward and away from, respectively, the geometric center of the device and associated parts thereof. Said terminology will include the words above specifically mentioned, derivatives thereof and words of similar import.
Referring to
The first ends of the jaw members are identified by numerals 46 and 48 and have steel pads 50 welded thereto. These pads each carry an array of sharpened spikes projecting from an outer surface thereof as is more clearly seen in the partial view of
The two jaw members 36 and 42 are pivotally coupled to one another by a pin or shoulder bolt 52 at a location that is offset from the opposed ends of the jaw members. The offset is such that the length of the jaw members between the location of the pivots 38 and 52 and between the pivots 44 and 52 is equal to the distance between the pivots 26 and 38 and 26 and 44 so as to create a four-bar linkage parallelogram.
With continued reference to
Having explained the constructional features of the pallet-puller tool of the present invention, consideration will next be given to its mode of operation.
In use, an operator will approach a pallet sitting on the floor while pulling on the knob 60 to force the jaw pads 50 to an open condition relative to one another so that they can be fitted on either side of the stringer 12 of a pallet to be manipulated. The tension on the cable 56 will then be released, allowing the spring 54 to cause the ends of the jaws to close relative to one another such that the spikes on the pads 50 press somewhat into the wood of the stringer 12. Now, when the operator pulls on the handle grip member 24 to pull the pallet, the spikes on the pad members 50 dig in even further. Thus, the pallet is both gripped and towed to a desired destination. At this point, tension is again applied to the cable 56, via the pull knob 60, to again force the jaw pads 50 apart relative to one another, releasing the pallet.
This invention has been described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and that various modifications, both as to the equipment and operating procedures, can be accomplished without departing from the scope of the invention itself.
