Abstract:
Ram air ventilation of the engine bay of an automotive vehicle is accomplished by providing ventilating openings in a transverse structural cross-member that bridges the front of the engine bay, and by collecting hot effluent from the radiator and condenser and directing same out of the engine bay.

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
     This invention relates to the ventilation of the engine bay of an automotive vehicle. 
     Most automobiles have the engine bay located at the front of the vehicle. Typically an internal structural cross-member bridges the front of the bay and supports the radiator that is a part of the engine&#39;s cooling system. When the vehicle is equipped with air conditioning, the condenser mounts in front of the radiator. The radiator and condenser are cooled by air that passes through them, the air either being forced through the radiator and condenser by ram air effect when the vehicle is in forward motion, and/or by being drawn through the radiator and condenser by a fan or fans located directly behind the radiator and condenser. As a result, the engine bay is ventilated by air that has been heated by the radiator and condenser. Before this air leaves the engine bay, it is further heated by the heat emitted directly by the engine. Consequently elevated temperatures can occur in the engine bay and at other locations that are exposed to the heated air leaving the engine bay. These elevated temperatures may be sufficiently high to create thermally induced problems in certain areas or components of an automotive vehicle. 
     The present invention relates to a new and unique arrangement for ventilating an engine bay to reduce temperatures. The invention involves the use of a ducted fan or fans to draw cooling air through the radiator and condenser and to convey the drawn air out of the engine bay so that hot effluent from the radiator and condenser does not ventilate the engine bay. The invention further involves the radiator and condenser mounting on an internal structural cross-member that bridges the front of the engine bay but with the radiator and condenser covering only a limited portion of the total open area of the cross-member. The remainder of the open area of the internal structural cross-member remains open so that ram air passes through this remaining open area to ventilate the engine bay. 
     While the use of ducted fans in association with the radiator of a motor vehicle is not broadly new, as evidenced by U.S. Pat. No. 4,082,344 and German OS No. 26 32 166, the prior art usage is for heating the engine bay. Moreover, the prior art does not integrate the ventilation system with an internal structural cross-member of the vehicle in the manner contemplated by the present invention. Accordingly, the invention is believed to constitute a significant development for reducing temperatures in the engine bay and at locations that are exposed to air that has ventilated the engine bay. 
     The foregoing features, advantages and benefits of the invention, along with additional ones, will appear in the ensuing description and claims which should be considered in conjunction with the accompanying drawings. The drawings disclose a preferred embodiment of the invention according to the best mode contemplated at the present time in carrying out the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective view of a representative installation in accordance with principles of the invention. 
     FIG. 2 is a side elevational view, on an enlarged scale and partly cross-section, of FIG. 1 showing the several parts in assembled relation. 
     FIG. 3 is an enlarged view taken in the direction of arrows 3--3 in FIG. 1. 
     FIG. 4 is an enlarged view taken in the direction of arrows 4--4 in FIG. 1. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The drawing figures show a representative configuration for an automotive vehicle engine bay ventilation according to the invention. The engine bay is represented by the numeral 10 and is schematically portrayed in FIG. 1. The engine bay is bounded at the rear by a dash panel 12 and at the sides by inner fenders 14 and 16 and these are also schematically portrayed. A portion of the hood 18 is shown in FIG. 2, as is the front end 20 of the vehicle. Inside the front end 20 and forwardly of the transversely mounted engine 21 is a transverse structural cross-member 22 that joins the inner fenders 14 and 16 across the front of the bay. Cross-member 22 has an open area comprising a number of openings 24, 26, 28, 30, 32, 34, 36, 38 that pass through the cross-member from front to rear. Heat exchanger structure is disposed in front of and mounted on the structural cross-member. This heat exchanger structure comprises a radiator 40 for engine 21, and when the vehicle has air conditioning, it further comprises a condenser 42. Radiator 40 has end tanks 44, 46 at the sides and a core 48 extending between said sides. The radiator attaches to cross-member 22 at points of attachment 50. Tubes 52 and 54 project rearwardly from the end tanks 44, 46 to provide for connection to hoses leading to and from the engine. The condenser attaches to the radiator at points of attachment 56. In the assembled condition, the radiator end tanks 46, 48 fit to the vertically elongated openings 28, 30 so that the tubes 52, 54 can project rearwardly through the respective openings. 
     Ducted fan structure, 58 generally, comprising two ducted fans 60 is cooperatively associated with the structural cross-member 22, radiator 40 and condenser 42. Each ducted fan comprises an inlet cone 62 and a scroll 64. The ducted fans are disposed directly behind the core areas of the radiator and condenser. Each cone 62 has an inlet opening 66 that matches the corresponding openings 32 and 34 of structural cross-member 22. Furthermore, each cone has a circular outlet opening 68 that is generally centrally located with respect to the inlet opening 66. Each scroll 64 comprises a circular inlet opening 70 that fits to the circular outlet opening 68 of the corresponding inlet cone. Furthermore, each scroll has an outlet opening 72 that is disposed to the side. Each inlet cone further contains a set of three struts 74 that support a motor mount 76 centrally of each outlet opening 68. An electric motor 78 is fitted to each mount and projects rearwardly to fit inside the corresponding scroll when the parts are assembled. The motor shaft 80 points to the rear and a fan 82 is disposed within the corresponding scroll and attached to shaft 80. With this arrangement the ducted fan structure is disposed on the engine bay side of the heat exchange structure and encloses the engine bay side of the heat exchange structure. 
     Whenever the fans 82 are operated by energizing the motors 78, they are effective to draw air through the core areas of the condenser 42 and radiator 40 so that the air passes through the inlet cones 62 and through scrolls 64 to be discharged at the scroll outlets 72. The scroll outlets 72 convey the hot effluent out of the engine bay by the outlets either passing through the inner fender walls 14 and 16 directly or else by connecting to ducts (not shown) which exit the engine bay. When the vehicle is in forward motion, ram air is forced through the condenser, the radiator and the ducted fans to be discharged via the outlets 72 if the fans are not operating. At the same time ram air is forced through the vertically elongated openings 24, 26, and the horizontally elongated openings 36 and 38 to ventilate the engine bay. The air that passes through these openings 24, 26, 36 and 38 is not heated by the condenser or radiator, and therefore the engine bay is ventilated with ambient air, not with effluent from the condenser and radiator. 
     It is contemplated that the structural cross-member 22 can be fabricated by any of several conventional techniques. For example it could be a stamped metal part or it could be a moulded structural plastic part. It is also possible that the inlet cones 62 could be integrally formed with the structural cross-member. The struts 74 and motor mount 76 can also be integrally formed with the inlet cone. 
     Scrolls 64 are fabricated to have an upper part 84 that can be disassembled from a lower part 86. This can provide access to the fans and motors if service is necessary. 
     The electric motor 78 and fans 82 are conventional and the scrolls 64 are constructed in accordance with conventional fabrication techniques. The ducted fans are preferably of a type that is commonly known as a mixed flow fan. 
     While a preferred embodiment of the invention has been disclosed, it will be appreciated that principles are applicable to other embodiments.