Ventilation – Vehicle – Having forced recirculation
Patent
1991-10-28
1994-05-03
Joyce, Harold
Ventilation
Vehicle
Having forced recirculation
454144, 454151, 454158, B60H 126
Patent
active
053082796
DESCRIPTION:
BRIEF SUMMARY
DESCRIPTION
1. Technical Field
This invention relates to an air circulatory system and more particularly to a system for environmentally conditioning the air circulating within a cab of a vehicle.
2. Background Art
In the operation of present day construction vehicles, the noise within the cab to which the operator is subjected is of ever increasing concern. One of the major contributors to the noise created within the cab is the heating, ventilating and air conditioning system which is commonly referred to as the HVAC. Noise within these systems can be created by numerous factors which include the number motors utilized to operate the blower fans and the speed at which the blower fans must operate to obtain a sufficient flow of air within the cab. These criteria are often times a result of the amount of restriction created by the duct work through which the air must flow and the resultant pressure drop which is created between the inlet and discharge sides of the blower assembly. As the restriction within the system increases, the pressure drop that exists between the inlet and outlet sides of the blower also increases. The greater the pressure drop, the higher the fan speed must be to create a sufficient flow of air to effectively ventilate the cab. Alternatively, multiple blowers may be utilized to increase the flow of air; however, both solutions have an adverse effect on the amount of noise created by the heating and air conditioning system.
Many times the amount of restriction created within the system is a function of available space in which the various components and duct work may be placed. For instance, it is always desirable to mix fresh air from outside the cab with air that is being recirculated within the cab. In many instances there is not enough room to locate duct work that is specifically dedicated to communicate fresh air into the system. As a result, it is very common to utilize the tubular framework that already exists in the structure of the cab as a duct to communicate the fresh air into the system. While this is a very efficient use of space and available componentry, it creates a relatively tortuous path through which the fresh air must traverse, thus increasing the amount of restriction within the system. An example of this type of design is disclosed in U.S. Pat. No. 4,365,541, issued to Marques et al. on Dec. 28, 1982.
Another source of restriction that is disclosed in the Marques et al. patent resides in the positioning of the filters for both the fresh air and the recirculated air. Again, since space is a very precious commodity, the filters for both sources of air have been positioned in the same area to facilitate serviceability. The filters are positioned in-line with each other in a generally common housing. The fresh air filter is positioned upstream of the recirculation filter leaving a relatively small space between the filters. The space serves as an inlet through which the recirculated air may be introduced into the flow of air that is drawn through the heating and air conditioning unit by the operation of the blowers. Because the inlet is so small, it is apparent that a rather large restriction is created. As a result, multiple blowers or a single blower with a very high fan speed is necessary to provide the system with sufficient air flow. This situation will ultimately result in an increase in the operational noise of the system.
The present invention is directed to overcoming one or more of the problems as set forth above.
DISCLOSURE OF THE INVENTION
In one aspect of the present invention an air circulatory system is provided for conditioning the environment of an enclosure. The system includes a housing that is positioned within the enclosure and has first and second portions. A means is provided for communicating ambient air from outside the enclosure into the first portion of the housing. A means is also provided for communicating air that circulates within the enclosure with the first portion of the housing to be mixed with the ambient air. A means for di
REFERENCES:
patent: 2970456 (1961-02-01), Rice
patent: 4088364 (1978-05-01), Termont
patent: 4344356 (1982-08-01), Casterton et al.
patent: 4467706 (1984-07-01), Batcheller et al.
patent: 4503749 (1985-03-01), Kuhn et al.
patent: 4612975 (1986-09-01), Ikari
patent: 4874036 (1989-10-01), Masuda
patent: 4989500 (1991-02-01), Anliker et al.
patent: 5119718 (1992-06-01), Wagner et al.
patent: 5131886 (1992-07-01), Haustein
Caterpillar Inc.
Joyce Harold
Perry William C.
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