Engine enclosure

[0002] 1. Field of the Invention

[0003] The present invention relates to vehicles having liquid cooled engines, and more specifically to an engine enclosure which is adapted to direct cooling air to and through the radiator while also serving to contain noise emitted by the engine.

[0004] 2. Description of the Related Art

[0005] Vehicles such as lawn tractors commonly utilize liquid cooled gas or diesel engines with air cooled radiators. Since these vehicles are often used in cutting grass and other vegetation, the air used to cool the radiator is frequently contaminated with dust, grass clippings and similar debris. A further problem can occur when the cooling air is drawn in and around the engine. This air can become heated by the engine and cooling of the radiator can become more difficult. When ducting structures are used to keep the air cool by guiding it around the engine and to the radiator, they can interfere with access to engine components for service and/or maintenance.

[0006] It would, therefore, be desirable to provide an engine enclosure for a liquid cooled engine which can provide a sufficient supply of air to cool the radiator and engine coolant circulating through it. It would also be desirable to provide the supply of air without the flow being interrupted or compromised due to blockages caused by dust, grass clippings or similar debris. It would further be desirable to prevent the air supply from being heated by the engine as it is drawn to and passed through the radiator. Also, it would be desirable that the air heated by passing through the radiator be exhausted in a manner that would not affect the operator or lawn being cut. It would be desirable as well to provide an air intake structure that would not interfere with servicing and/or maintenance of the engine and its components. Lastly, it would be desirable to provide an air intake structure that would serve to minimize the engine noise escaping from the engine compartment.

[0007] Towards these ends, there is provided an engine enclosure module which directs air from an inlet opening to the radiator of a liquid cooled engine. The module is comprised of a hood and baffle joined together to provide air passages between their adjacent surfaces. The air inlet is sized to provide a low flow rate that will minimize the buildup of dust, grass clippings and similar debris on the inlet screen. The inlet is located behind the operator station and substantially above the ground to reduce its exposure to dust and debris and it is positioned in a generally vertical orientation to minimize the entry of rain, leaves and/or related debris. Through locating the inlet opening adjacent to the operator station, any blockages can quickly be observed and the operator can brush any buildup from the screen without leaving the operator station.

[0008] The air passages between the surfaces of the hood and baffle structure separate the air from the engine as it is directed to the radiator. Air warmed after passing through the radiator is then exhausted out the back of the engine enclosure, away from the operator and parallel to the lawn being cut.

[0009] The spaced apart hood and baffle surfaces form acoustic air passages between them that serve to contain the engine noise within the compartment, and the modular one piece enclosure assembly allows it to be raised or easily removed to allow access to the engine and its components for service and/or maintenance. Noise reducing acoustic form panels are provided to selected hood surfaces to further reduce the engine noise escaping from the engine compartment.

[0010] With the present invention there is provided a modular engine enclosure that provides a high volume of air for cooling the radiator of a liquid cooled engine at a low flow rate to minimize the buildup of debris on the intake screen. The enclosure further provides cool air to the radiator, exhausts the used air out the back of the engine compartment and away from the operator, minimizes engine noise escaping from the engine compartment and permits quick, easy and unobstructed access to the engine compartment and its components.

[0011] FIG. 1 is a left side view of a vehicle of the type upon which the present invention could be utilized.

[0012] FIG. 2 is an exploded schematic view of the engine hood, baffle, radiator and major components contained within the enclosure.

[0013] FIG. 3 is a front view of the engine enclosure.

[0014] FIG. 4 is a view of the engine enclosure taken along lines 4—4 of FIG. 3, with arrows depicting the air flow.

[0015] FIG. 5 is an elevated perspective view of the engine enclosure.

[0016] FIG. 6 is an elevated front perspective view of the baffle, with the air flow patterns depicted by the letters A, B and C.

[0017] FIG. 7 is another view of the baffle, illustrating the air flow patterns A, B and C found respectively in the first, second and third air passages.

[0018] FIG. 8 is a right front elevated perspective view of the engine enclosure with portions of the hood removed to illustrate the structure of the baffle and the air flow patterns.

[0019] Looking first to FIG. 1, there is illustrated a commercial mowing vehicle 10 upon which the present invention could be utilized. The vehicle 10 includes a frame 12 supported on front and rear wheels 14-16, and has an operator station 18 at its forward end. A steering wheel 20 is supported on an upstanding pedestal 22 and foot and hand controls 24-26 are provided for operating the vehicle 10. At the rear of the vehicle 10 is carried an engine which is housed within an engine enclosure 28.

[0020] Looking now to the exploded view of FIG. 2, there is illustrated the essential components housed within the engine compartment. They include the engine 30 supported on the frame 12, a fan shroud 32 within which a fan 34 is rotatably housed, a radiator 36, radiator support posts 38, radiator mounting plate 40, support pan 42 and rails 44, a baffle 46 and hood 48. As shown in FIGS. 2, 3 and 4, the engine 30 is mounted on the frame 12 with the fan 34 being driven by an engine shaft 50. The fan 34 is housed within the fan shroud 32 which is also mounted on the engine 30. Carried above the fan 34 is the radiator 36 which is supported on the plate 40 and pan 42, which are in turn mounted to the radiator support posts 38. The posts 38 are mounted on the frame 12 to support the radiator 36 separate from the engine 30 and reduce the vibrations transferred to the radiator mountings. The rails 44 secure the radiator 36 to the pan 42 and plate 40. The radiator 36 is mounted horizontally above the engine 30 with the fan 34 being placed between it and the engine 30 to draw air through the radiator 36. The shroud 32 then directs the used air rearwardly and through an outlet opening 52 in a grill 54 at the rear of the hood 48, see FIG. 4.

[0021] Looking as well to FIG. 5, it will be seen that the engine enclosure 28, which is comprised of the hood 48 and baffle 46, covers the top, sides, front and rear of the engine compartment. The hood 48, best illustrated in FIGS. 2, 3, 5 and 8, is comprised of a front member 56 with an inlet opening 58 covered by a screen 60, a top member 62, a left side member 64 having respective rearwardly and downwardly extending portions 66-68, a right side member 70 with similar rearwardly and downwardly extending portions 72-74, and the rear member 54 which in the preferred embodiment takes the form of a grill through which used cooling air is exhausted.

[0022] The baffle 46, which is best shown in FIGS. 2 and 6, similarly includes a front surface 76, left and right surfaces 78-80 and a top surface 82. A large central outlet opening 84 and smaller front and rear side openings 86-88 in the top surface 82 provide for the flow of air to the top surface of the radiator 36 housed beneath the baffle 46. At the rear of the top surface 82 of the baffle 46 is provided a downwardly and rearwardly sloping surface 90 that abuts the top member 62 of the hood 48 and serves as a rear air deflector, see FIG. 4. At the forward edge of the central opening 84 is carried an upstanding curved wall surface or deflection surface 92 with notched openings 94 at each side. The center and side portions 96 of this air deflecting wall 92 extend to the underside of the top member 62, see FIGS. 3 and 4. As shown in FIGS. 6 and 8, structure 98 taking the form of an “X” is attached to and extends between the side portions 96 of the wall 92 and rear portion 100 of the top surface 82 to support the top member 62 of the hood 48.

[0023] As shown in FIG. 4, the hood 48 and baffle 46 provide a modular enclosure which directs air from the inlet opening 58 at the forward end of the engine compartment to the radiator 36 and exhausts it out the outlet opening 52 in the back of the enclosure 28. The air flow as well as its direction of movement is depicted by arrows in FIGS. 4, 6 and 8. To direct the air to the radiator 36 and exhaust it, the enclosure 28 includes, first, second and third air stream paths or passages, which are formed between the spaced apart members of the hood 48 and surfaces of the baffle 46. The air flow patterns within each of these passages are designated by the letters A, B and C respectively in FIGS. 4, 7 and 8. Passage A is formed between the front member 56 and the screened- in front surface 76, the two passages designated B are formed between the pairs of side members and surfaces 64-78 and 70-80, and passage C is formed between the top member 62 and top surface 82.

[0024] Looking again to FIG. 4, there is illustrated an air cleaner inlet tube 102 at the rear of the outlet opening 84 in the top surface 82. This tube 102 takes the form of a snorkel and draws air from the rear central portion of the outlet opening 84 to supply the engine air cleaner intake line 105. The tube 102 is provided with its inlet opening 104 at the underside of its forward end to draw cool air from the air supplied by all three passages A, B and C.

[0025] Additionally provided on the downwardly extending portions 68-74 of the side members 64-70 of the hood 48 is a foam sound absorbing material 106. Similar foam material 108 is also provided on the underside of the top member 62 of the hood 48 and the rear side of the upstanding wall 92 is also provided with foam 110. This sound absorbing material 106, 108 and 110 is added to assist in containing the emission of noise generated by the engine 30 and can be particularly useful when utilized in a vehicle 10 having a diesel engine. Through adding it on the top member 62 and upstanding wall 92, many of the engine sound waves which pass out the central opening 84 are absorbed before they can escape through the screen 60. Further assisting in containing the emission of sound from the front, side and top of the engine compartment are the acoustic air barriers provided by the double walled air passages between the hood 48 and baffle 46. The hood 48 and baffle 46 of the preferred embodiment additionally assist in containing the engine sounds since they are comprised of a plastic or composite material.

[0026] The vehicle 10 would typically be used with a mower deck supported at its forward end to cut grass and similar vegetation. During the cutting of such grass and vegetation, dust, grass clippings and similar debris would be thrown into the air surrounding the vehicle 10 due to the operation of the cutting blades. Through providing the screened inlet opening 58 for the cooling air rearward of the operator station 18, and at a somewhat elevated level, the amount of air with contaminants entering the inlet opening 58 is reduced. With the inlet opening 58 oriented generally vertically, rain, leaves and similar debris are prevented from entering.

[0027] During operation, air drawn by the fan 34 will enter the screened inlet opening 58 and flow in streams along passages A, B and C as illustrated in FIGS. 6 and 7. The hood 48 has been removed from these views to better illustrate the air flow patterns and passages found between the members of the hood and surfaces of the baffle. Initially, the air will enter the first stream or passage A between the front member 56 of the hood 48 and the front surface 76 of the baffle 46. As illustrated in FIGS. 6, 7 and 8, part of the air entering through the screen 60 will also be drawn to each side and into the two second passages B between the left side member 64 and left side surface 78 and the right side member 70 and the right side surface 80. In the preferred embodiment, these side surfaces 78-80 are triangularly shaped, but could take other shapes that include triangularly shaped portions therein. Yet another part of the air will be drawn upwardly and over the top of the front surface 76 to pass through the third passage C between the top surface 82 and the top member 62.

[0028] As the air moves along the two passages B, most of it will be drawn through the central outlet 84 opening provided in the top surface 82 while some of it will enter the rear side inlets 88. As air moves through the third passage C, some of it will be drawn into the front side outlets 86, some will be deflected around the upstanding wall 92 and into the central opening 84, some will pass over the notched openings 94 of the wall 92 and into the central opening 84 and some will flow to the side openings 88 at the rear of the baffle 46. In this way, air is provided to the top surface of the radiator 36 at its front, central and rear portions to be drawn through it and cool it evenly. After passing through the radiator 36, the fan 34 exhausts the air generally horizontally through the grill member 54 of the hood 48.

[0029] The enclosure further serves to contain noise generated by the engine and isolate it from the operator, as well as those who would be adjacent the operation of the vehicle. This is accomplished not only through placing the sound absorbing material along the lower portions of the respective left and right side members, the underside of the top member of the hood and the rear surface of the upstanding wall 92, but also through the use of the double walled air passages with space between them that serve as sound insulators.

[0030] With the present invention, there is provided an engine enclosure that utilizes their respective spaced apart surfaces to provide passages for directing air to the radiator. The passages further serve, along with sound absorbing foam, to contain engine sounds within the enclosure. The modular construction of the enclosure allows the enclosure to be raised or removed to allow service and maintenance to the engine and its components.