Patent Application
20060242934
The present invention generally relates to air filter assemblies for use on devices such as air compressors, and more specifically, to air filter housing assemblies having replaceable filter elements.
Air filter assemblies are known in the art for receiving and enclosing air filters that are used in industrial applications such as air compressors, vacuum pumps, and the like. Current assemblies generally include an air filter element, a receptacle for receiving the air filter, a retaining ring and a cover for enclosing the air filter in the housing. In addition, the receptacle typically includes at least one opening in its end cap which is configured to introduce the fluid, either gaseous or liquid, that is to be filtered.
Current air filter housings generally include at least two pieces that are mechanically fastened together by staking, welding, orbital riveting, or locking with screw threads and a jam nut, or similar technologies which are known in the art. Generally, this two-piece construction consists of a cup-shaped receptacle and a nipple extending from a base of the receptacle. The process of manufacturing such multi-piece housings can be costly and time consuming. In addition to possible cost problems, the fastener used to attach the pieces can become loosened during operation of the compressor, which can eventually cause one of the pieces, such as the nipple, to become separated from the housing. This reduces the effectiveness of the assembly, and potentially causes malfunctions in, or damage to the compressor, for example through the admission of unwanted particulates.
Furthermore, if a piece of the housing, such as the nipple, were to break off during compressor operation, the entire air filter assembly typically requires removal from the compressor and replacement. Another potential problem is when one of the screws or fasteners used to hold the components of the housing together becomes loosened, and as a result, must be tightened. Solving these potential problems can be difficult tasks, because the assembly is generally difficult to access within the tight confines of the compressor. In some cases, special tools may be required. As a result, replacement of the assembly, the air filter, or the tightening of the housing components can be very time-consuming, thus reducing the efficiency of the compressor.
In addition, current air filter assembly end caps are not always resilient enough to withstand the shock caused during compressor operation. Current end caps are generally manufactured out of relatively hard plastic or sheet metal, which can become weakened and break due to shock forces generated during compressor operation, causing leaks that can contaminate the compressor. These plastic end caps can also become weakened as a result of the high operational compressor temperatures, again causing breakage or leakage. These problems can reduce both the efficiency and life of the assembly, because the filter elements or other components damaged by the fractured end cap may need to be replaced more often.
Finally, current plastic end caps can emit noise during compressor operation as it vibrates against the housing, which can be unpleasant for individuals present during operation.
Therefore, there exists a need for an improved air filter assembly in which the housing and its components will not break or become loosened during compressor operation. There also exists a need for an improved air filter assembly that is easily accessible and whose components are easily removable from the assembly housing without the use of tools. In addition, there exists a need for an improved air filter assembly end cap that is designed to withstand the shock and reduce the noise generated during compressor operation. Finally, there exists a need for an improved air filter assembly that is cost effective.
The above needs are met or exceeded by the present air filter assembly for use in an air compressor, featuring an end cap that is easily removable from the housing without the use of tools, so that the air filter can be easily replaced. In addition, the present air filter assembly end cap is manufactured out of a resilient material that can withstand the shock and reduce the noise generated during compressor operation. Finally, because of the resiliency and flexibility of the present air filter assembly end cap, it is easily accessible within the cramped confines of the compressor. The present assembly also features a unitary housing, thereby increasing the cost effectiveness of the assembly. Unlike current assemblies, whose components may need to be tightened because of the shock caused during compressor operation, the present unitary housing is intended to overcome this problem. Because the housing is unitary, maintaining the stable construction of the housing does not require the use of tools.
More specifically, the present air filter assembly includes an air filter housing having a base, a sidewall, and an upper end, being configured for receiving an air filter element; and an end cap configured for attachment to the upper end of the housing without the use of tools.
In another embodiment, the present air filter assembly includes an air filter element; an air filter housing configured for receiving the air filter element, the housing having a lip, a generally cylindrical sidewall extending from the lip, a base with a centrally located opening, and a nipple surrounding the opening; and an end cap having a top and a depending skirt.
In yet another embodiment, the present air filter assembly includes an air filter element; an air filter housing configured for receiving the air filter element, the housing having an upper end, a generally cylindrical sidewall extending from the upper end, a base with a centrally located opening, and a nipple surrounding the opening; and an end cap having a top and a depending skirt, the end cap being configured to encase the upper end of the housing.
Referring to
The air filter housing 14 is configured for receiving the air filter element 12. As is known in the art, the air filter element 12 generally includes a top side 24, a bottom side 26, and a filter media 28 such as corrugated paper disposed between the top side and the bottom side. However, it is contemplated that the air filter element 12 can include additional components, as are known in the art.
Referring next to
It is preferred that the housing 14 is a unitary piece that is integrally formed, preferably by means of aluminum die cast manufacturing, as is known in the art. However, it is appreciated that other conventional manufacturing technologies are available to produce unitary housings. It is contemplated that the unitary housing 14 is more cost-effective than current air filter housings that generally contain at least two pieces that are joined together by staking, welding, orbital riveting, or locking with screw threads and a jam nut, as are known in the art. It is further contemplated that the present unitary housing 14 with the integral nipple 32 can withstand more shock than current housings, where the nipple is a separate piece and can break off or become loosened during operation, possibly causing damage to the air compressor. As a result of the above-mentioned advantages of the present unitary housing 14, it is contemplated that the working life of the assembly 10 will be increased.
Referring again to
Referring to
The end cap 22 includes a top 38 and a skirt 40 depending from the top in the direction of a longitudinal axis of the housing 14. As seen in
It is further contemplated that, unlike conventional air filter assemblies, the present end cap 22 is relatively easily accessible within, and removable from, the compressor without the use of tools, due to the resiliency of the end cap and the snap-fit relationship between the lip 36 and the undercut 44 of the depending skirt 40. Although a snap-fit relationship is disclosed in the present assembly, it is appreciated that other known tool-free attachment structures are suitable.
The end cap 22 is preferably manufactured from a rubber or rubber-like resilient material, and it is appreciated that a variety of known resilient materials are suitable. It is preferred that the end cap 22 have a Durometer in the range of 55 to 90, with an optimal Durometer of 70. It is contemplated that in this range, the end cap 22 will have an optimal resiliency for withstanding the shock and vibrations generated during compressor operation. A feature of the present end cap 22 is that it is more resilient to shock and high temperatures than current end caps, which are generally manufactured from plastic and can crack or fracture when subjected to operational shock and vibration.
It is further contemplated that, unlike current plastic end caps, the present end cap 22 will reduce or dampen the noise produced during compressor operation. This is due to the resiliency of the end cap 22, which is softer than the plastic end caps of current assemblies, and as a result will not generate as much noise as it vibrates against the housing 14. Finally, it is contemplated that because of the resilient material used to make the end cap 22, it will be more accessible than current plastic end caps, which are more rigid and can become too hot to touch shortly after cessation of compressor operation.
In addition, because of the flexibility of the end cap 22, it is contemplated that the shape of the end cap 22 can be temporarily distorted to allow it to be snapped into or removed from the housing 14 in the tight confines of the air compressor.
Referring now to
As seen in
While a particular embodiment of the present air filter assembly has been described herein, it will be appreciated by those skilled in the art that changes and modifications may be made thereto without departing from the invention in its broader aspects and as set forth in the following claims.
