Strapping tool

A strapping tool for tensioning a strap around a load, adhering the strap onto itself, and cutting a feed end of the strap, includes a body having a foot on which the strap is disposed during a strapping cycle. The body housing and/or forming a part of a tensioning element and including a welding element. One or more pneumatic motors tension the strap and drive the welding element. A pneumatic module is mounted to the body. The module has a compressed gas inlet to the module and is configured for controlling the flow of compressed gas to the one or more motors. A handle is mounted to the body and operably connected to the pneumatic module. The handle is configured for manipulating the tool and includes an actuator for permitting and isolating the flow of compressed gas to the pneumatic module. The handle is orientable so as to allow a user to select a desired handle orientation for operation of the strapping tool. At least one hold-down finger is mounted at about the foot to temporarily hold the strap on the foot during tool operation.

BACKGROUND OF THE INVENTION

The present invention pertains to an improved, hand-held pneumatic strapping tool. Strapping tools are well-known in the art. These tools come in a wide variety of types, from fully manual tools to automatic, table-top tools. Tools are generally designed for use with either metal strapping or plastic/polymeric strapping.

Hand-held pneumatic (plastic) strapping tools are commonly used in the field, in manufacturing facilities and the like for on-the-spot application of strapping material to a load.

Powered or driven tools are usually either electrically or pneumatically driven. This is necessary in order to provide energy for tensioning the strapping material and adhering the strap onto itself. Typically, the adhering function is provided by melting or otherwise welding a section of the polymeric (plastic) strapping material onto itself. Examples of such tools are disclosed in Rometty et al., U.S. Pat. No. 6,732,638, Crittenden, U.S. Pat. No. 6,966,255 and Nasiatka et al., U.S. Pat. No. 7,155,885, all of which are commonly assigned with the present application and invention and all of which are incorporated herein by reference.

In certain applications, the strapper is used in a vertical orientation rather than a horizontal orientation. As such, the strapper may be awkward to use, while trying to position and secure strap within the sealing jaws or sealing region, and while attempting to operate the strapping tool.

It has also been observed that after a strap seal is formed, the leading end (the cut end) of the strap can fall from the strapper, which requires the operator to retrieve the strap and refeed it into the strapper to commence a subsequent strapping operation.

Accordingly, there is a need for a pneumatic strapping tool that secures the strap material in the tool during and following strapping operations. Desirably, such a tool is configured for ergonomic use in a vertical orientation as well as the (conventional) horizontal orientation. More desirably, such an ergonomic design facilitates operation in the vertical (and horizontal) orientations.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the figures and in particular toFIG. 1, there is shown a strapping tool10, having hold-down fingers12and an ergonomic, pneumatic actuator integrated handle14, embodying the principles of the present invention.

The strapping tool10includes, generally, a body16that encloses the tool components to tension, seal, and cut the strap S. A pneumatic module18is part of the tool10and is mounted to the body16. The tool10is operated by pneumatic pressure supplied by an outside source. One or more pneumatic motors20function to tension the strap S and seal a course of the strap S onto another course of the strap S. During the sealing operation, the strap S is held between an anvil22, located on the foot24of the tool10and a weld pad26that is spaced from the anvil22. A cutter (not shown) is also disposed at about the weld pad26to sever the strap S from the strap S supply so the looped portion of the strap S is freed from the source.

When the tool10is used, the cut end of the strap S typically slips from the tool10. This requires an operator to pick up the strap from the floor and reposition the strap S in the tool, create a loop of strap S around the load and tighten the strap S before commencing the strapping (sealing) cycle.

The present tool10includes hold-down fingers12disposed on each side of a foot24(enveloping the weld pad26/anvil22and cutter). The hold-down fingers12are biased (as by a spring28) to a closed position, that is, to hold down the strap S. As can be seen inFIGS. 3-5the strap S is positioned under the hold-down finger12(between the hold-down finger12and the foot24), and is maintained in place by the spring force acting on the hold-down finger12. The strap S can be slid, transversely across the hold-down finger12and longitudinally along the hold-down finger12. The hold-down finger12is intended to prevent the strap S from slipping from the foot, not to rigidly lock the strap S in place. The hold-down fingers12have curved free ends30to facilitate readily slipping the strap S under the hold-down fingers12, without undue effort.

The hold-down fingers12pivot about a pin29that mount the hold-down fingers12to the foot24. The pin29can be located between the spring28and the curved free end so that the spring28is not in the strap path—that is, out of the way of the strap in the strapper.

As seen inFIGS. 1,2,6, and7, the tool10has an ergonomic handle14that is integrated into the pneumatic system32. The handle14is configured having a curved shape (as indicated at34) so the operator can position his or her hand on the handle14with their hand (their fingers) oriented in a vertical plane. It has been found that it is easiest to manipulate the tool10and most comfortable to use the tool10with the user's hand in the vertical plane (as seen inFIG. 1). However, the handle14can be rotated (see adjusting nut36) to any orientation to meet a desired orientation.

Known pneumatic strapping tools have actuation levers, switches or buttons located on the tool, generally on the tool body or on the pneumatic module to commence the strapping (welding) cycle. While this functions perfectly well for most strapping tools and specifically for tools used in a horizontal orientation, it may not be especially ergonomically efficient for tools that are used in a vertical orientation. Accordingly, in the present strapping tool10the handle14is integrated into the pneumatic system32with an actuator button or switch38located on the end40of the handle14. In this manner, as seen inFIG. 1, the operator holds the handle14(gripping portion42) in his or her hand, with their fingers wrapped around the gripping portion and with their thumb resting on the actuator switch38. In this manner, the strapping tool10can be manipulated and operated with one hand while, for example, the strapping tool10is suspended from a cable C or the like. The integrated handle14is configured such that the actuator switch (button)38is formed as part of a pneumatic switch or plunger (piston) within the pneumatic circuit.

It will be appreciated that although the present hold-down fingers12and ergonomic handle14(integrated into the pneumatic system) are shown on a strapping tool10having only a welding or sealing function, it will be appreciated that the present strapping tool10can be used on any of a wide variety of strapping tools, including full-function tools (e.g., those having a tensioning cycle as well), which strapping tools are within the scope and spirit of the present invention.

All patents referred to herein, are hereby incorporated herein by reference, whether or not specifically do so within the text of this disclosure.