Chalk boxes are well known in the construction field and have long been used to mark construction lines. The chalk preferred for use as the marking medium is brightly colored and indelible, leaving a readily visible and enduring chalk line not easily obscured by the heavy foot traffic inherent at a construction site. One persisting problem with known chalk boxes is their tendency to leak chalk dust, both when the line is extended during use and also during carrying between uses. Chalk dust leakage is a problem for several reasons. One such reason is that indelible chalk dust produces a brightly colored stain that is difficult to remove from clothing and/or other surfaces that are not desired to be marked. Finely powdered chalk dust tends to have almost-liquid flow characteristics, and thus even if the chalk box is carried in a pocket, the leaked chalk dust does not long remain confined. Further, as construction technology progresses, increasingly complex and delicate electronic tools, equipment, and measurement devices are becoming commonplace at the work site. These tools, such as computers, laser measurement devices, ultrasonic probes, and the like are all susceptible to damage from dust contamination. While care is taken to protect them from airborne dust intrusion, accidental direct introduction of chalk dust from the clothing or hands of an operator could cause expensive and time-consuming equipment damage. Moreover, leaked chalk dust staining the work site can obscure or confuse the intentionally laid chalk lines, again resulting in the need for repeated measurements and other costly delays, decreasing productivity at the work site. Finally, chalk dust leakage necessitates more frequent replacement of the chalk dust in the chalk box, again decreasing efficiency and productivity.
Typically, the worker using the chalk box also makes other measurement markings at the construction site. Some of these markings involve using regular or colored pencils. When these pencils become dull, the worker typically uses a knife or utility blade to crudely sharpen them, a process that is inefficient and wasteful in that useful pencil is typically shaved off along with the wood. Since workers must carry their equipment with them, most find it inconvenient to carry a small, loose pencil sharpener when they already have a knife. Providing a pencil sharpener that does not add to the number of tools the worker must carry would therefore increase efficiency and enhance productivity.
At the work site, productivity is one of the keys to remaining competitive and making a profit. Tools that decrease work site delays and increase efficiency and productivity therefore help to increase profit. Therefore, a need arises for a chalk box that minimizes chalk dust leakage. There is a further need for providing a pencil sharpener that does not further encumber the worker. The present invention satisfies these needs.
USPTO Backgrounds
USPTO Backgrounds