Patent Application
20080236518
The present disclosure relates to fan shrouds for use in the engine compartment of automobiles. More particularly, the present disclosure relates to a two piece fan shroud assembly that snaps together in one simple motion to provide a sturdy and reliable assembly.
The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Automotive vehicles typically utilize an internal combustion engine to provide the power to operate the vehicle. Internal combustion engines generate heat due to the combustion process and it is necessary to continuously remove the excess heat from the vehicle's engine in order to maintain the operating temperature of the vehicle's engine at a specified level.
The usual method of removing this excess heat is an automotive cooling system. The cooling system utilizes a coolant pump which pumps coolant through the vehicle's engine to absorb the excess heat and then this heated fluid is pumped to a heat exchanger or radiator which removes the excess heat by performing a heat exchange process with ambient air. The coolant which has been cooled by the radiator is returned to the engine and the process continuously repeats itself. Typically, the temperature of the coolant is maintained at a minimum level using a thermostat or some other type of control system.
In order to reduce the size and thus the costs of the radiator, the automotive designer strives to have the radiator operate in the most efficient manner. One method used to maximize the efficiency of the radiator is to control the flow of ambient air through the radiator. This is accomplished by providing a fan which draws the ambient air through the radiator and then providing a fan shroud which ensures that the maximum amount of air is drawn through the radiator.
Automotive fans for the cooling system can be electrically driven or they can be driven by the vehicle's engine. Regardless of how they are driven, the maximization of ambient air flow requires that the fan be located within the fan shroud. The use of a fan that is driven by the engine and a fan shroud which is attached to the radiator presents problems during the assembly of the vehicle. In many cases, the vehicle frame, drive train and suspension are constructed first and the fan is attached to the driving component of the engine such as a coolant pump pulley or the crankshaft of the engine. The vehicle's body, including the radiator and fan shroud, is not assembled to the frame, drive train and suspension assembly until near the end of the assembly line. Since the fan needs to be located within the fan shroud, an interference/clearance issue is created when the body, including the radiator and fan shroud are lowered onto the frame.
This interference/clearance issue has been addressed by designing the fan shroud such that it has a removable portion at the bottom of the shroud in order to provide clearance for the fan during the assembly of the body to the frame. Once the body has been assembled to the frame, the removable portion is attached to the fixed portion of the shroud to avoid significant air loss through the radiator.
The connection between the removable portion and the fixed portion must be very secure. If it were to become detached during the life of the vehicle, it could lead to undercooling of the vehicle's engine due to a loss of ambient air through the radiator, or it could come loose and interfere with and possibly damage the fan itself. While it is necessary to adequately secure the removable portion to the fixed portion of the shroud, it still needs to be removable for any service required to the fan. Typically, the only access to the fan is through the removable portion of the fan shroud. Finally, the assembly of the removable portion to the fixed portion of the fan shroud has to be a simple and rapid assembly process in order to accommodate the vehicle as it moves down the assembly line.
The present disclosure provides a two-piece fan shroud which includes a removable portion and a fixed portion. The assembly of the two pieces is accomplished using a locating feature and an integral clip thus eliminating the need of any additional fasteners. The assembly of the two pieces can be completed in seconds using a single hand from underneath the vehicle. The assembled fan shroud is robust and secure yet the fan shroud can still be disassembled easily for any service that is required.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.
A fan shroud assembly 20 is attached to radiator 12 and located in a position that circumferentially surrounds coolant fan 14 in a generally coaxial relationship. When coolant fan 14 is rotated, ambient air from in front of radiator 12 is drawn through radiator 12 to cool the coolant flowing between engine 10 and radiator 12. Fan shroud assembly 20 covers the rear portion of radiator 12 to ensure that only ambient air from in front of radiator 12 is drawn through radiator 12 in order to maximize the ambient air flow through radiator 12 and thus maximize its cooling capacity
Fan shroud assembly 20 comprises a fixed fan shroud 30 and a removable fan shroud 32 both of which are molded plastic components. While fixed fan shroud 30 and removable fan shroud 32 are described as plastic components, it is within the scope of the present invention to utilize any suitable material for fixed fan shroud 30 and removable fan shroud 32. Removable fan shroud 32 is detachable from fixed fan shroud 30 to create an opening 34 which provides clearance for coolant fan 14 during the assembly of the vehicle's body to the vehicle's frame.
Fixed fan shroud 30 includes a generally rectangular portion 36 at one end which transitions into a generally circular portion 38. A semi-circular flange 40 extends axially from circular portion 38 to provide a portion of fan shroud assembly 20 within which coolant fan 14 is located. Fixed fan shroud 30 defines a plurality of mounting supports 42 which are utilized to secure fixed fan shroud 30 to radiator 12.
Removable fan shroud 32 includes a semi-circular portion 44 which mates with semi-circular flange 40 to define a generally circular aperture 46 within which coolant fan 14 is located as illustrated in
Upper latching system 48 includes a pair of latches 52, with each latch 52 being located on an opposite end or side of fan shroud assembly 20. Since both latches 52 are identical except for being on opposite ends or sides of fan shroud assembly 20, only one latch 52 will be detailed. It is to be understood that the opposite latch 52 includes the same elements as those detailed below.
Latch 52 includes a female portion 54 located on fixed fan shroud 30 and a male portion 56 located on removable fan shroud 32. Female portion 54 includes a generally rectangular housing 60 which defines an aperture or slot 62 which is open toward the lower portion of fixed fan shroud 30 where removable fan shroud 32 is assembled. An angular wall 64 extends downward from rectangular housing 60 to provide a guiding surface for male portion 56 as described below. A rear wall 66 of rectangular housing 60 defines a retention opening 68 for retaining male portion 56 also as is detailed below.
Male portion 56 includes a retention finger 70 which circumferentially extends from opposite circumferential ends of semi-circular portion 44 of removable fan shroud 32 to engage female portion 54 of fixed fan shroud 30. Retention finger 70 defines a retention tab 72 which engages with retention opening 68 to secure removable fan shroud 32 to fixed fan shroud 30 as detailed below.
Lower latching system 50 comprises a plurality of retention walls 80 extending from semi-circular portion 44 of removable fan shroud 32. The present disclosure illustrates three retention walls 80 but there can be two or more retention walls 80 if desired. The plurality of retention walls 80 illustrated includes a first retention wall 82, a second retention wall 84 and a third retention wall 86 arranged circumferentially along a forward edge of semi-circular portion 44 of removable fan shroud 32. Retention walls 82-86 extend generally over the entire inner circumferential edge of semi-circular portion 44 with a gap 88 being located on opposite sides of second retention wall 84.
Second retention wall 84 is disposed between first and third retention walls 82 and 86. Second retention wall 84 extends from an inside surface 90 of semi-circular portion 44 while first and third retention walls 82 and 86 extend from an outside surface 92 of semi-circular portion 44. Thus, as illustrated in
An inside surface 94 of first retention wall 82, an inside surface 96 of second retention wall 84 and an inside surface 98 of third retention wall 86 each define one or more retaining members 100 which extend radially towards circular portion 38 of fixed fan shroud 30. Circular portion 38 of fixed fan shroud 30 defines a plurality of apertures 102 each of which accepts a respective retaining member 100 to secure removable fan shroud 32 to fixed fan shroud 30.
The assembly of removable fan shroud 32 to fixed fan shroud 30 begins by aligning removable fan shroud 32 with fixed fan shroud 30 as illustrated in
The assembly of removable fan shroud 32 to fixed fan shroud 30 to create fan shroud assembly 20 is completed without the use of additional fasteners or clips. Thus, the assembly can be completed by hand in a minimum of time without using tools. The assembled fan shroud assembly 20 is a robust design because of the circumferential length of retention walls 82-86 and it can be easily disassembled by releasing retaining members 100 from apertures 102 which will allow the rotation of removable fan shroud 32 such that retention tabs 72 will be released from retention openings 68 thus allowing for the easy removal of removable fan shroud 32.
