Patent Application
20090094953
The present invention relates to a filter element including at least one flat element wound into a compact body through which fluid to be filtered flows axially between its two axial end faces, the end of the flat element being fixed to the outer side of the compact body by an adhesive element. The present invention also relates to a method for sealing an outer end of a compact filter element with the adhesive element.
Compact air filter elements are known in the prior art. These filter elements are formed of a corrugated or pleated filter paper and a smooth filter paper. The filter papers are bonded together and then tightly wound together to form a filter element of the desired size. A first band of adhesive is applied to one margin of the smooth filter paper, and a second band of adhesive is applied to another margin of the smooth paper filter on the opposite side at the opposite end of the filter paper. Thus, when the corrugated and smooth filter papers are wound together and the adhesive bands solidify, intervening spaces between the corrugated and the smooth layer are alternately closed at the two end faces to prevent direct flow through the channels formed between the filter papers. A fluid stream, particularly air taken in by an internal combustion engine and flowing from the unfiltered air side to the filtered air side flows initially only into a dead-end channel, then through the filter paper and out of an oppositely oriented dead-end channel on the other side. Compared to conventional pleated filters, these compact air filters have the advantage of offering either a larger filter surface for the same overall size or the same filter surface in a smaller overall size.
After the winding of the filter element, the end of the paper needs to be hermetically sealed. The sealing of the end of the paper prevents unwinding of the compact filter element and seals the filter element to prevent unfiltered air from entering the filter element from the side thereof. Known compact filter elements use an adhesive hot melt, i.e., an adhesive that acts as a liquid when sufficiently heated, but becomes a solid when cooled, to seal and fasten the end of the filter element.
The process variability of the hot melt operation, however, creates a significant variation in the amount of hot melt disposed on the filter element. The difficulty in controlling the hot melt process creates quality problems in the seal provided by the hot melt adhesive. Also, the cycle time of the hot melt operation is a limiting factor in a filter element production line.
It is an object of the present invention to provide an improved compact filter element. It is another object of the present invention to provide a method for applying the adhesive element to the compact filter element.
These and other objects and advantages are achieved in accordance with the present invention by providing a compact filter element with an adhesive element having a predetermined size and shape, such as an adhesive tape, and a method for sealing the same. The adhesive element according to the present invention provides better control of the amount of adhesive applied to the filter, because the adhesive element has a predetermined amount of adhesive. Thus, the costs associated with the adhesive process can be reduced, by minimizing excessive use of adhesive. Also, the process of applying the adhesive element according to the present invention is a faster process and requires less expensive equipment to implement than the hot melt process. Additionally, the quality and consistency of the compact filter element and the seal at the end of the paper thereof are significantly improved.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
The invention will be described in further detail hereinafter with reference to illustrative preferred embodiments shown in the accompanying drawing figures, in which:
An adhesive element 210 is attached at the outer end 201 of the filter material 202, thereby fixing the position of the end 201. The adhesive element 210 may be attached to the filter material 202 by an adhesive element applying device or by hand. The adhesive element 210 fastens the end 201 of the filter material 202 to the outside of the filter element 200, thereby preventing the filter material 202 from unwinding. Additionally, the adhesive element 210 seals the end 201 of the filter material 202 to prevent unfiltered air from entering the filter element from the side thereof
The adhesive element 210, unlike an adhesive hot melt, has a solid structure before, during and after installation thereof. According to illustrative embodiments of the present invention, the adhesive element 210 has a predetermined size, shape and thickness. The size and (rectangular) shape of the adhesive element 210 illustrated in
According to an illustrative embodiment of the present invention, the adhesive element 210 may be an adhesive tape having a predetermined size and shape. The adhesive tape has a solid part with an adhesive backing to attach the outer end of the wound filter material to the filter element. The adhesive tape may be any type of adhesive tape having appropriate characteristics for sealing and fixing the end of the filter material to the outside of the filter element.
According to an illustrative embodiment of the present invention, the adhesive element may include information such as part numbers, company names, mounting instruction and/or company trade name for advertising, etc. This information may be printed on the outer side of the adhesive element, for example, where it can be viewed by a user.
The adhesive element according to the present invention is easier to apply than a hot melt adhesive, which involves a complicated and expensive process. Moreover, the equipment used to apply the adhesive element is less expensive than the equipment used to apply the hot melt adhesive. Accordingly, the present invention provides a savings in capital equipment cost and production cycle time, as well as a labor cost advantage. Further cost reduction could be expected due to the saving of maintenance cost or downtime because of faulting equipment. Additionally, the present invention provides a cost reduction due to reduction of the quantity of adhesive applied and more consistent dispensing of the adhesive.
The foregoing description and examples have been set forth merely to illustrate the invention and are not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed broadly to include all variations within the scope of the appended claims and equivalents thereof.
| Number | Date | Country | |
|---|---|---|---|
| 60978993 | Oct 2007 | US |
