Multi-shell air-tight compartmentalized casings

This application claims priority benefit to Application No. 61043820 filed Apr. 10, 2008.

Not Applicable

Not Applicable

The present invention relates generally to tool casings and, more particularly, to air-tightly sealed split-shell casings, especially for motor driven pneumatic tools, including vacuum and non-vacuum sanding and grinding tools.

The background information discussed below is presented to better illustrate the novelty and usefulness of the present invention. This background information is not admitted prior art.

Power tools require a covering or casing to protect their electronic and/or moving components. Such tools would soon be ruined if used without some kind of protective covering, as the electronic and/or moving components of the tools are easily affected by dust and moisture. Depending on the size, shape, and power source of the tool, the tool\'s protective casing can be manufactured as one-piece or multi-piece covers. Presently, all pneumatic tools use single shelled casings because of the seal that is required for the vacuum and/or exhaust chamber. All electric tools whether they are a vacuum type tool or not utilize a split shell design. Electric vacuum type tools, however, are not very effective because their split shell casing can not completely seal their vacuum chamber.

The present Inventor realized that manufacturing pneumatic tools using only a one-piece air-tight shell created many problems. The size, number, shape, and complexity of each tool component must be designed to fit into the one-piece air-tight shell. Additionally, when designing a single shelled housing for a pneumatic tool, the process is restricted to the mold-ability of the housing. This means that each housing must be designed to provide for the housing to be able to be ejected from the mold in which it is formed. Therefore the look and feel of the tool might be compromised to provide for the housing to be moldable. This requirement complicates the design, manufacturing, and assembly processes, and, furthermore, results in a heavier and perhaps bulkier and less ergonomic than desired tool and increases costs.

These concerns prompted the present Inventor to design an air-tight split-shell protective casing for pneumatic and other tools. As described below, split-shell casings, made according to the principles of the present invention, provide for an air-tight seal between the split-shell sections. Moreover, the degree of shape complexity and the number of features of both the tool to be housed and its housing easily and cost-effectively can be increased when a two or more multiple pieces housing design is used in place of a single-shell housing. At the same time, the air-tight sealable split-shell housings, as taught herein, provide for a reduction in the design complexity of the housing and tool that is required by a single shell design to provide for a fit between the tool and the housing, thus, simplifying manufacturing and assembly, and reducing overall costs. These cost reductions enable the production of split-shell housed tools that are more affordable for all. Moreover, split-shell cased tools are able to have a higher power to weight ratio, thus, providing for smaller, lighter tools to accomplish the same tasks as single-shell cased tool counterparts. Additionally, split-shell casings, made following the principles of the present invention, are rigid, strong, and capable of withstanding harsh operating conditions. Split-shell cased tools are easy to hold and are ergonomic in that the casings reduce tool-produced vibrations that otherwise would be adsorbed by a user\'s hands.

It should be noted that the present invention resides not in any one of these features per se, but rather in the particular structure of the components and the combinations of the features herein disclosed that distinguishes the present invention. It will be shown that the casings made according to the principles of the invention provide a sealing means that securely attaches two half-shells of a two-section split-shell casing to each other, so that for all tools so cased, without or with vacuum capabilities, which vacuum may be self-generated or supplied from a central vacuum device, the multiple-part protective shell provides an air-tight seal. The addition of the sealing means of this invention to a split-shell casing effectively creates a sealed chamber that can be used effectively in both vacuum or exhaust sections of the tool.

All of these benefits are made possible by providing for a tool casing, comprising:

at least two casing sections so molded that once positioned about a tool to be encased and joined together at their sealing perimeters with seals therebetween form an air-tight casing for encasing a tool, where a groove is molded into the sealing perimeter of one casing section forming a grooved casing section, a seal is inserted into the groove. A protruding ridge that is molded into the sealing perimeter of the casing section that is to be joined to the grooved casing section is adapted for compressing the seal inserted into the grooved casing section providing for an air-tightly sealed casing when the two sections are joined.

Furthermore, wherein each of at least two casing sections is so contoured as to provide air-tightly sealable inner-casing compartments for receiving tool components to be encased and wherein opposing joining perimeters of the air-tightly sealable inner-casing compartments are adapted with the grooves and protruding ridges, respectively.

The components to be encased are contemplated to be tools, such as a pneumatic tool, such as a central or self-generating vacuum pneumatic tool.

Each casing section comprises a molded firm inner layer coated by an outer pliant overmolded layer, where the molded firm inner layer may comprise a firm plastic layer and the molded outer pliable overmolded layer may comprise a urethane overmolded layer.

And, where the air-tightly sealable inner-casing compartments may comprise a first air-tightly sealed molded chamber for accommodating an exhaust chamber, a second molded chamber for accommodating an exhaust tube and an inlet tub, and a second air-tightly sealed molded chamber for accommodating a vacuum chamber.

Additionally, there is provided a method for making a multi-shell casing, comprising: