Patent Publication Number: US-2007119395-A1

Title: Cooling device of vehicle

Description:
BACKGROUND OF THE INVENTION  
      The present invention relates to a cooling device of a vehicle that comprises a radiator to cool cooling water, an electric fan, a fan shroud and the like, which are disposed at a front portion in an engine room.  
      Conventionally, a cooling device of a vehicle, in which an electric fan, radiator and condenser to cool the cooling water and coolant are assembled to the fan shroud, is known. According to the cooling device, traveling air is taken in by the electric fan, the cooling water of the radiator and the coolant of the condenser are cooled with the traveling air, and the engine room is scavenged with the traveling air taken in (i.e., exhaustion of heated air).  
      Herein, there is a problem in that the above-described structure may cause the following concern. Namely, when a vehicle travels at a low speed, the electric fan can supply a sufficient amount of traveling air passing thorough a fan opening portion at the fan shroud, thereby ensuring desirable cooling function. When the vehicle travels at a high speed, however, these fan and fan shroud may become an obstacle to increase of an improper flow resistance, so that the amount of traveling air taken in would be reduced and thereby the cooling efficiency would be deteriorated.  
      Then, in order to solve this problem, there has been an improved device, as disclosed in Japanese Utility Model Laid-Open Publication No. 62-195624, in which openings (air through hole) are formed at the fan shroud in addition to the fan opening portion for the electric fan, and doors are provided at the openings so as to be opened by the traveling air. Herein, when the vehicle travels at the high speed, the doors are opened by the traveling air and the sufficient amount of traveling air flows in through these openings. Thereby, the cooling function of the radiator and condenser and the scavenging function can be ensured properly even at the vehicle high-speed traveling state.  
      Meanwhile, recent vehicle developments have been requiring a more efficient space designing for the front portion of engine room. Namely, since ensuring a roomy cabin space and a proper safety against a vehicle frontal crash has been required particularly, it has become more difficult to properly layout components surrounding the engine in the engine room for ensuring the sufficient space at the front portion in the engine room. Especially, for the vehicle whose engine is disposed laterally in the engine room, such layout of components, such as auxiliary parts or pipes, is rather difficult due to a considerably limited layout space exiting around the engine.  
      Specifically, in a case where the cooling device disclosed in the above-described publication is provided in front of the engine, there is a concern that pipes or the like that are disposed between the cooling device and the engine would interfere with the doors provided at the fan shroud when the doors are opened.  
     SUMMARY OF THE INVENTION  
      The present invention has been devised in view of the above-described problem, and an object of the present invention is to provide a cooling device of a vehicle, which includes a fan shroud comprising an opening portion for an electric fan and openings with doors, that can properly prevent the doors from interfering with any other parts in an engine room.  
      According to the present invention, there is provided a cooling device of a vehicle, in which a cooling unit comprising a radiator and a fan shroud supporting an electric fan is disposed in front of an engine in an engine room, a plurality of openings are formed at the fan shroud so as to be located substantially vertically in line beside the electric fan, and doors are provided respectively at the openings so as to be opened by traveling air, wherein the fan shroud is configured in such a manner that an opening position of at least one of the openings is located forward relative to that of another one of the openings and a position of a rear end of the door provided at the one of the openings is located forward relative to that of a rear end of the door provided at the another one of the openings in a state where the doors are opened.  
      Accordingly, even when the vehicle traveling speed is low, a sufficient cooling air for the radiator can be endured by the electric fan and the fan shroud, and when the vehicle traveling speed becomes high, the doors provided at the fans shroud are opened by the traveling air and the traveling air can be allowed to come in to the engine room efficiently. Thus, the cooling function of the radiator and the scavenging function of the engine room can be improved. Also, since the position of the rear end of the door provided at the one of the openings is located forward relative to that of the rear end of the door provided at the another one of the openings in the state where the doors are opened, a layout space for pipes or the like behind the door can be ensured properly. Thereby, there can be provided properly a compact layout of the fan shroud in a narrow engine room without interference with any other components/parts.  
      According to an embodiment of the present invention, the engine is disposed laterally in such a manner that an intake manifold thereof is located at a front portion in the engine room, a transmission is disposed beside the engine, the electric fan is supported at one side of the fan shroud, and the fan shroud is provided in such a manner that the electric fan is located substantially in front of the transmission and the plural openings are located substantially in front of the engine.  
      Accordingly, the compact layout of the fan shroud having the electric fan and the like in front of the laterally-disposed engine can be attained. Namely, the transmission does not generally project forward so much compared to the laterally-disposed engine equipped with the intake manifold and the like at its front. Thus, by applying the layout in which the electric fan having a certain rearward projection is located substantially in front of the transmission and the plural openings are located substantially in front of the engine, a gap formed between the fan shroud and the engine can be made as narrow as possible, thereby attaining the compact layout of the fan shroud.  
      According to another embodiment of the present invention, the cooling unit further comprises a condenser provided substantially in front of the radiator, the opening position of the opening that is located at a relatively upper level of the fan shroud is located forward relative to that of another opening that is located at a relatively lower level of the fan shroud, and the door provided at the opening that is located at the relatively upper level is located at a position where a rear end part thereof does not interfere with a pipe that is provided to be coupled to the condenser in the sate where the door is opened.  
      Generally, the condenser is provided along with the radiator and the fan shroud, so the pipe coupled to the condenser may be disposed near the fan shroud. Herein, by applying the layout in which the door at the opening located at the relatively upper level of the fan shroud is located forward relative to another door at the opening located at the relatively lower level of the fan shroud, any interference of rear end part of the doors with the pipe can be prevented surely in the state where the doors are opened.  
      According to another embodiment of the present invention, the doors provided at the openings have substantially an identical shape. Thereby, the layout in which the opening position of at least one of the openings is located forward relative to that of another one of the openings can bring up the layout in which that the position of the rear end of the door provided at the one of openings is located forward relative to that of the rear end of the door provided at the another of openings in the state where the doors are opened. Thus, reduction of manufacturing costs can be also improved.  
      Herein, it is preferable that the fan shroud be formed in a bowl shape to project rearward so that the traveling air can be gathered at the fan opening portion as much as possible and the traveling air can be supplied efficiently into the engine room by the electric motor at the vehicle low-speed traveling state. However, the above-described forward-location of the openings and doors might. cause a concern that the sufficient amount of the traveling air could not be gathered at the fan opening portion and thereby the cooling function of the condenser and the radiator or the scavenging function of the engine room might be deteriorated.  
      Meanwhile, there is generally provided a front grill to let a large amount of traveling air flow in to the engine room at a front portion of the vehicle. Herein, a lower opening portion located at a relatively lower part of the engine room is configured to be relatively large sized to intake much of the air easily, while an upper opening portion located at a relatively upper part of the engine room is configured to be relatively small sized not to intake so much of the air easily.  
      However, the above-described forward-location of only the opening(s) and the door(s) that are located at the upper part of the fan shroud would not influence badly on the entire supply function of the traveling air. Because, as described above, the amount of traveling air that flows in through the upper opening portion is originally small, compared to the traveling-air amount flowing in through the lower opening portion. Thus, the entire supply function of the traveling air that may be affected mainly by the traveling air flowing in through the lower opening portion would not be influenced badly by the above-described forward-location, and thus the proper layout space of the pile or the like, which is described above, can be ensured properly.  
      Other features, aspects, and advantages of the present invention will become apparent from the following description which refers to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a schematic diagram of a vehicle front portion in an engine room of an automotive vehicle equipped with a cooling device of a vehicle according to an embodiment of the present invention.  
       FIG. 2  is a sectional view of an example of the vehicle front portion, taken along line II-II of  FIG. 1 .  
       FIG. 3  is a perspective view of a cooling unit.  
       FIG. 4  is a rear view of a radiator equipped with a fan shroud, when viewed from the rear of the vehicle.  
       FIG. 5  is an enlarged perspective view showing a position relationship between door openings of the fan shroud and an inlet pipe. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      Hereinafter, a preferred embodiment of the present invention will be described referring to the accompanying drawings. The following descriptions are just about an example of the present invention, and therefore these descriptions should not limit any application or usage of the present invention.  
       FIGS. 1 and 2  show a vehicle front portion in an engine room of a vehicle equipped with a cooling device according to an embodiment of the present invention. An engine  1  equipped with a super charger is disposed laterally in such a manner that an intake manifold  12  is located at a front portion in the engine room. A transmission  2  is disposed beside the engine  1 , and a metal-made intercooler  3  is disposed above the engine  1  slantingly in such a manner that its rear end is positioned above its front end (see  FIG. 2 ). Herein, illustrating of a hood and part of bumper is omitted in  FIG. 1 .  
      The intercooler  3 , which has substantially a rectangular shape, is covered by an intercooler cover  4  from its top. The cover  4  has a wide area that is enough to cover over the entire top of the intercooler  3 , and part of the cover  4  that corresponds to the intercooler  3  has a grid shape so as to allow traveling air to come in toward the intercooler  3 .  
      Below a hood  6 , as shown in  FIG. 2 , is provided an intercooler duct  5  to take in the traveling air to the intercooler  3  so as to extend from the front to the intercooler  3 . This duct  5  is made of a resin material and has a flat shape to form an air passage S therein. The duct  5  has an air inlet port  5   a  with a flat shape at its front end. Thus, the traveling air taken in from the inlet port  5   a  is supplied to the intercooler  3  via the air passage S in the intercooler duct  5 .  
      In front of the engine  1  is provided a shroud frame  10  supporting. a cooling unit  7  (cooling device) that comprises a condenser  21  and a radiator  22 . The shroud frame  10  comprises a cooling-unit support portion  10   a  to support the cooling unit  7  and connecting portions  10   b ,  10   b  that extend from the support portion  10   a  rearward and laterally and are fixed to a vehicle body, respectively, which has substantially a bowl shape as a whole, when viewed from above. The cooling unit  7  is configured to cool cooling water of the engine  1  and coolant of an air conditioner with the traveling air that comes in through a front grill  9 , which is formed below a bumper  8  with a bumper beam  8   a  and the like, and an air inlet  11 , which is formed above the bumper  8 .  
      As shown in  FIG. 2 , the traveling air coming in through the front grill  9  mainly flows down toward a lower part of the cooling unit  7 , and the traveling air coming in through the air inlet  11  mainly flows down toward an upper part of the cooling unit  7 . Herein, since the air inlet  11  has a considerably smaller passage section than the front grill  9 , the air-flow amount from the inlet  11  is rather small compared to that from the front grill  9  does. Accordingly, cooling function of the cooling unit  7  or scavenging function of the engine room may be influenced primarily by the flow amount of the air passing through the lower part of the cooling unit  7 , not so much by the flow amount of the air passing through the upper part of the cooling unit  7 .  
      The cooling unit  7  is formed by assembling the condenser  21 , radiator  22 , and fan shroud  23  which are disposed in order from the front, as shown in  FIG. 3 . The traveling air flows down passing through the condenser  21  and radiator  22 , whereby the coolant of the air conditioner flowing in the condenser  21  and the cooling water of the engine flowing in the radiator  22  can be cooled. The condenser  21  and the fan shroud  23  are held by hooks  22   c ,  22   c , . . . provided at the radiator  22 , which will be described below in detail.  
      The radiator  22 , which is formed in a flat shape as shown in  FIG. 4 , is a cross-flow type of radiator in which there are provided a cooling-water outlet portion  22   f  to be coupled to a cooling-water pipe feeding the cooling water from the radiator  22  to the engine  1 , a cooling-water inlet portion  22   g  to be coupled to another cooling-water pipe feeding the cooling water from the engine  1  to the radiator  22  at its both-side ends. Namely, tank portions  22   a ,  22   b  filled with the cooling water are located at the both sides in a vehicle width direction, and a core portion comprising fins and tubes (not illustrated) is located at its center portion between the tank portions  22   a  and  22   b.    
      At front and rear faces of the tank portions  22   a ,  22   b  are respectively provided a plurality of hooks  22   a ,  22   c , . . . to hold the fan shroud  23  and the condenser  21  (only hooks to hold the fan shroud  23  at the rear face are illustrated in  FIG. 4 ). At upper and lower ends of the tank portions  22   a ,  22   b  are respectively provided pin portions  22   d ,  22   d ,  22   e ,  22   e  to be inserted into engagement holes formed at the cooling-unit support portion  10   a  of the shroud frame  10 .  
      Herein, a mounting member, not illustrated, is configured to engage with tip portions of the above pin portions  22   d ,  22   d ,  22   e ,  22   e  that have been inserted into the engagement portions of the shroud frame  10 . A resilient member is provided between the radiator  22  and the shroud frame  10 , so the cooling unit  7  with the radiator  22  and the condenser  21  is supported resiliently at the shroud frame  10 .  
      The condenser  21  is also, as shown in  FIG. 3 , formed in the flat shape so as to extend in the vehicle width direction like the radiator  22 . The coolant of the air conditioner flows in a longitudinal direction in the condenser  21 . Namely, the condenser  21  comprises, like the radiator  22 , a core portion  21   c  comprising fins and tubes and tank portions  21   a  and  21   b  provided at its both sides. To the tank portions  21   a ,  21   b  are coupled an inlet pipe  31  to feed the gas-state coolant to the tank portions from an evaporator of the air conditioner via a compressor, and an outlet pipe  32  to feed the liquid-state coolant cooled at the core portion  21   c  to the evaporator.  
      Hereinafter, the inlet pipe  31  will be described in detail. The inlet pipe  31  is one that is provided between a compressor  33  to increase temperature and pressure of the gas-state coolant from the evaporator and the tank portion  21   a  of the condenser  21 . It has an observing window  31   a  for checking the flow of coolant at its middle portion. This window  31   a  is located at a portion near an upper portion of the engine room so as to provide an easy checking. Meanwhile, since the compressor  33  is generally located at a lower portion of the engine room, the inlet pipe  31  interconnecting the compressor  33  and the condenser  21  needs to be provided so as to extend from the lower portion to the upper portion of the engine room. Also, since there is little space in front of the engine  1  of the engine room as shown in  FIG. 1 , the inlet pipe  31  may pass in back of the cooling unit  7 , namely just behind the fan shroud  23 .  
      The fan shroud  23  is made of resin and has the bowl shape, which is provided behind the radiator  22 . It has also a fan opening portion  23   a , in which an electric fan  24  is provided, and a door opening portion, which includes a plurality of door openings  23   c  (air-passing through holes) and doors  23   d . These opening portions  23   a ,  23   b  are disposed side by side as shown in  FIG. 4 . The fan shroud  23  is attached to the radiator  22  in such a manner that the door opening portion  23   b  is located on the side of engine  1  and the fan opening portion  23   a  is located on the transmission  2 . Thus, the fan opening portion  23   a  with the electric fan  24  is disposed on the side of the transmission  2  that does not project forward very much. Accordingly, the distance between the engine  1 /the transmission  2  and the cooling unit  7  can be made small, thereby providing a compact layout in the narrow engine room.  
      The fan opening portion  23   a  is configured to project rearward and has a recess portion for accommodating the electric fan  24  therein in a state where the fan shroud  23  is installed in the engine room. Its center has an through hole  23   e  for providing a motor  24   a  of the fan  24 . And, at the fan opening portion  23   a  is provided an opening  23   f  that are disposed in a donut shape to encompass the though hole  23   e . There are also provided a plurality of ribs that extend radially and a plurality of enforcing ribs that interconnect the ribs at the opening  23   f.    
      According to the above structure, the traveling air passing through the condenser  21  and the radiator  22  flows in the engine room via the fan opening portion  23   a  under the operation of the electric fan  24 . Herein, a state of the operation of the electric fan  24  includes a situation where the vehicle travels at a low speed and therefore a sufficient amount of traveling air to cool the condenser  21  and radiator  22  and scavenge in the engine room may not be obtained. Meanwhile, when the sufficient amount of the traveling air is obtained at the high-speed traveling state, the operation of the electric fan  24  may cause an improper increase of flow resistance and thereby the scavenging function and the like may be deteriorated to the contrary. Accordingly, in this case the traveling air is supposed to be allowed to pass through the door opening portion  23   b  and to flow in the engine room.  
      A plurality of door openings  23   c ,  23   c , . . . , which are substantially rectangular-shaped opening with a laterally-elongated shape, are formed substantially vertically in line on the door opening portion  23   b . And, the doors  25 ,  25 , . . . are provided at the door openings  23   c ,  23   c , . . . to as to be rotable. Specifically, as shown in  FIG. 5 , each door  25  has likewise substantially a rectangular shape so as to cover the door opening  23   c . To the door  25  are fixed pins  26  that extend laterally, both ends of which are pivotally supported at both ends of a frame portion of each door opening  23   c . A fixing position of the pin  26  to the door  25  is offset upward from the center of the door  25  in the vertical direction.  
      This offset fixing of the pin  26  to the door  25  can facilitate a smooth rotation of the door  25  according to the traveling air coming in from the front and provide a proper closing of the door opening  23   c  by the door  25  due to its weight when the door  25  does not receive any force of the traveling air or the like.  
      As described above, at the fan shroud  23  are provided the fan opening portion  23   a  with the electric fan  24  and the door opening portion  23   b  where the doors  25  open or close the door openings  23   c  according to the traveling air. Accordingly, when the vehicle traveling speed is so low that the traveling air is not sufficient, the operation of the electric fan  24  can ensure the cooling function of the condenser  21  and the radiator  22  and the scavenging function of the engine room. Meanwhile, when the sufficient traveling air is provided as the vehicle traveling speed increases, the traveling air can be also allowed to come in through the door opening portion  23   b , thereby ensuring the above functions.  
      And, the door opening portion  23   b  is configured in such a manner that its upper part is located forward relative to its lower part. Namely, the opening position of the top two door openings  23   c ,  23   c , which are located at a relatively upper level, is located forward relative to that of the other door openings  23   c ,  23 , . . . , which are located at a relatively lower level. And, the position of rear ends of the doors  25 ,  25  at these two top door openings  23   c ,  23   c  is located forward relative to that of rear ends of the other doors  25 ,  25 , . . . in a sate where the doors are opened.  
      Specifically, a slant portion  23   g  is formed on the door opening portion  23   b  between the upper part and the lower part. Thereby, the positions of the door openings  23   c ,  23   c  and the doors  25 ,  25  that are positioned above the slant portion  23   g  are located forward relative to the positions of the other door openings  23   c ,  23   c , . . . and the other doors  25 ,  25 , . . . that are positioned below the slant portion  23   g . According to this structure, the upper-positioned doors  25 ,  25  can be properly prevented from interfering with the above-described inlet pipe  31  that extends vertically just behind the fan shroud  23  (see  FIGS. 2 and 5 ).  
      The fan shroud  23  is formed in the bowl shape so that the traveling air can be gathered at the fan opening portion  23   a  as much as possible. Accordingly, the above-described forward-location of the door openings  23   c ,  23   c  may cause a concern that a sufficient amount of the traveling air could not be gathered at the fan opening portions  23   a  and thereby the cooling function of the condenser  21  and the radiator  22  or the scavenging function of the engine room might be deteriorated.  
      However, since, as described above, the mount of the traveling air that flows down from the front grill  9  to the lower part of the cooling unit  7  is much larger than that of the traveling air that flows down from the air inlet  11  formed at the bumper  8  to the upper part of the cooling unit  7 , the forward-location of only the door openings  23   c ,  23   c  and the doors  25 ,  25  that are located at the upper part of the door opening portion  23   b  would not influence badly on the entire cooling function of the cooling unit  7  or the scavenging function of the engine room.  
      Accordingly, interference of the doors  25 ,  25  provided at the fan shroud  23  with the inlet pipe  31  of the condenser  21  can be prevented surely without providing any bad influence on the cooling function of the condenser  21  and radiator  22  or the scavenging function of the engine room.  
      According to the above-described embodiment, since the positions of the door openings  23   c ,  23   c  which are located at the relatively upper level of the door opening portion  23   b  of the fan shroud  23  and the doors  25 ,  25  provided at these door openings  23   c ,  23   c  are located respectively forward relative to those of the other door openings  23   c ,  23   c , . . . , and the other doors  25 ,  25 , a layout space for the pipe can be provided just behind the fan shroud  23 .  
      Further, since the fan shroud  23  is configured in such a manner that the door opening portion  23   b  is located on the side of engine  1  that projects forward and the fan opening portion  23   a  is located on the transmission  2  that does not project forward very much, a compact layout of the cooling unit  7  in the narrow engine room can be provided.  
      Also, since the fan shroud  23  is configured in such a manner, as described above, that the opening position of the door openings  23   c ,  23   c  which are located at the relatively upper level of the door opening portion  23   b  of the fan shroud  23  is located forward relative to that of the other door openings  23   c ,  23   c , . . . , the above-described function and effect can be obtained even by using substantially an identical shape/size of the doors  25 ,  25 , . . . provided at the door openings  23   c ,  23   c , . . . Thus, manufacturing costs can be also reduced.  
      The present invention should not be limited to the above-described embodiment, and any other modifications and improvements can be applied. For example, although the positions of the upper door openings  23   c ,  23   c  and the upper doors  25 ,  25  are located respectively forward relative to those of the other door openings  23   c ,  23   c , . . . , and the other doors  25 ,  25  in the above-described embodiment, the door openings  23   c  and doors  25  whose positions should be located forward relative to others may be properly selected according to the layout of the pipe or the like. Also, the number of such door openings  23   c  and doors  25  whose positions should be located forward should not be limited to the two, and any other number, one or three or more, may be applied.