Abstract:
A method and system are provided which substantially reduce the disadvantages and problems associated with previous methods and systems for dampening vibration noise of a system component. Two shot injection molding of the component housing support integrates rigid and dampening portions that install the component in the system with vibration dampening.

Description:
RELATED APPLICATIONS  
       [0001]    This application generally relates to U.S. patent application Ser. No. 10/152,594, entitled “Method and System for Vibration Dampening,” filed on May 21, 2002 and having a common inventor and assignee. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    The present invention relates in general to the field of dampening vibrations, and more particularly to a method and system for information handling system component mounting with vibration dampening.  
           [0004]    2. Description of the Related Art  
           [0005]    As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.  
           [0006]    Information handling systems having played an important role in improving worker and individual productivity by automating tasks and performing complex computations. For instance, information handling systems commonly perform day-today operations in banks, libraries, research facilities, homes and other locations where workers and individuals spend significant amounts of time in quiet thought to accomplish complex tasks. Information handling systems assist by quietly tracking financial transactions and inventory, by acting as word processors that record research results or by connecting to networks to transfer valuable information on a timely basis. Under a number of circumstances in which information handling systems operate, quiet operation is an important consideration for users.  
           [0007]    One difficulty with keeping information handling system operations as quiet as possible is that the electronic components that perform or support information handling tend to generate heat that typically must be removed by cooling fans in order to ensure proper operation. Cooling fans often represent the greatest noise producing component of an information handling system. As information handling systems have grown more powerful with greater power consumption and faster operating speeds, the need for cooling has increased, leading to the use of more powerful cooling fans that operate at higher speeds and for greater time periods. To reduce the vibration and related noise of cooling fans, cooling fans are typically installed into information handling systems with vibration dampers, such as elastic washers or grommets that absorb vibrations. However, these vibration dampening pieces increase the complexity of manufacturing information handling systems since they are often small pieces that are manually installed with cooling fans.  
         SUMMARY OF THE INVENTION  
         [0008]    Therefore a need has arisen for a method and system which mounts information handling system components with a housing having integrated vibration dampening to decrease system noise.  
           [0009]    A further need exists for a method and system which incorporates vibration dampening for a system component without substantially increasing the complexity of assembling the component in an information handling system.  
           [0010]    A further need exists for a cooling fan housing with integrated dampening proximate the mount of the cooling fan housing to the chassis of an information handling system to reduce noise associated with cooling fan operation.  
           [0011]    In accordance with the present invention, a method and system are provided which substantially reduce the disadvantages and problems associated with previous methods and systems for dampening vibration noise of a system component. Two shot injection molding of the component housing support integrates rigid and dampening portions that install the component in the system with vibration dampening.  
           [0012]    More specifically, an information handling system cooling fan housing is molded as a single piece that includes a dampening portion to dampen vibrations generated through cooling fan operation and a rigid portion for supporting the cooling fan. The cooling fan housing defines a cooling air channel for the cooling fan to pass cooling air through in order to cool heat-generating components of the information handling system. The cooling fan housing mounting point to the information handling system integrates a dampening material to couple the housing to the information handling system and dampen vibration noise from cooling fan operations. The cooling fan housing has a rigid portion formed by a substantially rigid material that defines the cooling air channel and provides support to secure the cooling fan, and has a dampening portion formed by a vibration-absorbing material that attaches to the information handling system or is proximate an attachment device to absorb vibration transferred from the cooling through the housing. A cooling fan couples to the cooling fan housing and the cooling fan housing couples to an information handling system to align cooling air flow to remove heat from heat-generating components.  
           [0013]    In one embodiment, the cooling fan housing is formed as a single, integrated piece with a two shot plastic injection. A substantially rigid plastic is injected in one shot to form the cooling fan housing so that it supports a cooling fan and defines a cooling air channel. An elastic plastic is injected in another shot to form the dampening portion of the cooling fan housing mounting point. For instance, the elastic material is injected into a tool during formation of the cooling fan housing to form an attachment device that couples to an attachment point of the information handling system. The attachment point is formed as a male member having an attachment ring to secure the housing to the information handling system. For instance, a nipple at the end of the male attachment member pulls through a female opening of the information handling system housing with the attachment ring flexing to fit through the opening and then expanding to hold the male member secure. The two shot injection molding process produces a single fan housing assembly piece with the vibration-absorbing elastic portion of the cooling fan housing mounting point integrated with the rigid portion of the cooling fan housing. Thus, assembly of the information handling system involves coupling the cooling fan housing mounting point attachment device to the information handling system without separate vibration absorbing grommets or pieces.  
           [0014]    The present invention provides a number of important technical advantages. One example of an important technical advantage is that vibration dampening provided for a component decreases the noise associated with operation of the component. For instance, a cooling fan operates in an information handling system with vibrations isolated by an elastomer vibration dampening portion of the cooling fan housing proximate the mounting point of the housing to the information handling system, while a rigid portion of the cooling fan housing holds the fan securely in position. The information handling system operates quietly, providing an environment more conducive to concentration by information handling system users.  
           [0015]    Another example of an important technical advantage of the present invention is that information handling system assembly is simplified. For instance, the use of two shot plastic injection to form a single integrated component housing piece having a rigid support portion and an elastic attachment portion provides reduced assembly steps for installing a component into an information handling system with vibration dampening. The integrated vibration dampening section of the component housing eliminates or reduces the need for assembling additional vibration absorbing grommets or other devices, thus reducing manual labor and costs associated with information handling system assembly. Moreover, a component housing with integrated dampening reduces design complexity by solving vibration dampening at the component housing instead of at the design of the information handling system housing. Thus, separate vibration isolation is not required for separate information handling system housing chassis since the isolation material is incorporated in the component housing. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    The present invention may be better understood, and its numerous objects, features and advantages made apparent to those skilled in the art by referencing the accompanying drawings. The use of the same reference number throughout the several figures designates a like or similar element.  
         [0017]    [0017]FIG. 1 depicts a side view of a block diagram of an information handling system;  
         [0018]    [0018]FIG. 2 depicts a side cutaway view of a cooling fan housing mounted to an information handling system with supports having integrated dampeners;  
         [0019]    [0019]FIG. 3 a  depicts a side cutaway view of an information handling system elastic mounting point integrated with a rigid housing mounting support;  
         [0020]    [0020]FIG. 3 b  depicts a side cutaway view of an information handling system elastic screw attachment device; and  
         [0021]    [0021]FIG. 3 c  depicts a side cutaway view of an information handling system rigid mounting point proximate an integrated dampening section. 
     
    
     DETAILED DESCRIPTION  
       [0022]    Information handling systems are often used in noise-sensitive environments so that quiet operation is an important design consideration. The use of a cooling fan assembly, with integrated vibration dampening, aids in reducing the noise and vibration put out by an information handling system. For purposes of this application, an information handling system may include any instrumentality or aggregate of instrumentalities operable to compute, classify, process, transmit, receive, retrieve, originate, switch, store, display, manifest, detect, record, reproduce, handle, or utilize any form of information, intelligence, or data for business, scientific, control, or other purposes. For example, an information handling system may be a personal computer, a network storage device, or any other suitable device and may vary in size, shape, performance, functionality, and price. The information handling system may include random access memory (RAM), one or more processing resources such as a central processing unit (CPU) or hardware or software control logic, ROM, and/or other types of nonvolatile memory. Additional components of the information handling system may include one or more disk drives, one or more network ports for communicating with external devices as well as various input and output (I/O) devices, such as a keyboard, a mouse, and a video display. The information handling system may also include one or more buses operable to transmit communications between the various hardware components.  
         [0023]    Referring now to FIG. 1, a side cutaway view of information handling system  10  is depicted with a cooling air flow provided by a cooling fan  14 . Information handling system  10  includes electronic components that generate heat. If heat-generating components are not cooled, such as with a cooling air flow, failure of the heat-generating or other heat sensitive components may occur. One primary source of heat generation is a power supply  16 , which typically accepts external AC power and transforms the AC power into DC power of predetermined voltages for use by information handling system electronic components. Power supply  16  provides power to cooling fan  14  through a power line  18 . Another primary heat generating component is a CPU  20  which performs computations to support information handling functions. Typically, the faster a CPU operates, the more heat it generates and the more specialized and critical the transfer of heat from the CPU becomes. Thus, powerful CPUs generally depend on strong cooling air flow for proper operation. Other heat-generation components depicted in information handling system  10  include a hard drive  22  and memory  24 . In other embodiments, a variety of electronic components may be included that also generate heat, such as system control and graphics processors.  
         [0024]    Referring now to FIG. 2, a side cutaway view of a cooling fan assembly is depicted with integrated vibration dampening. A cooling fan housing  26  defines a cooling air channel  28  through which cooling fan  14  draws or pushes a cooling air flow. Power line  18  provides power to operate cooling fan  14  through a controller  30 . Controller  30  varies cooling fan operation to adjust the strength of the cooling air flow as needed to maintain a predetermined temperature range within information handling system  10 . Cooling fan  14  and controller  30  are mounted to a cooling fan mount  32  so that cooling fan  14  is held disposed in cooling air channel  28  by support members of mount  32 . Cooling fan  14  couples to cooling fan mount  32  which couples to cooling fan housing  26  to firmly support cooling fan  14  within cooling air channel  28 , resulting in the transmission of vibration during operation of cooling fan  14  to housing  26 . In alternative embodiments, cooling fan  14  couples to housing  26  with a variety of attachment configurations so that some vibrations produced by operation of cooling fan  14  are transferred to housing  26 .  
         [0025]    Cooling fan housing  26  couples to information handling system  10  with one or more mounting points  34  that are integrated with cooling fan housing  26 . Thus, during assembly of an information handling system, cooling fan  14  and cooling fan housing  26  are assembled into a cooling fan assembly and installed in information handling system  10  as a unit for ease of handling. A mounting point  34  of housing  26  has an attachment device  36  that secures housing  26  to openings  38  formed in the housing wall of information handling system  10 . Mounting point  34  is manufactured with a dampening material, such as an elastomer or other flexible material, that is integrated with a generally rigid material that forms the rest of housing  26 . Mounting point  34  forms attachment device  36  which secures housing  26  to information handling system  10 .  
         [0026]    In one embodiment, mounting points  34  are integrated with cooling fan housing  26  as a single piece by forming the piece with two shot plastic injection. One shot of the two shot plastic injection forms cooling fan housing  26  with a substantially rigid material to support the weight and operation of cooling fan  14  and to define air channel  28 . Another shot of the two shot plastic injection forms mounting points  34  integrated with housing  26  with the mounting points formed from an elastic material that absorbs vibrations associated with operation of cooling fan  14 . The two shot plastic injection integrates the rigid and elastic portions of housing  26  and mounting point  34  into a single piece that both firmly couples cooling fan housing  26  to information handling system  10  and absorbs vibrations from cooling fan  14  coupled to cooling fan mount  32 . In alternative embodiments, additional dampening portions may be included at various positions of the cooling fan housing proximate the mounting point to provide dampening as needed. Further, two shot injection with rigid and elastic material may form supports with integrated dampening for a variety of applications beyond cooling fan dampening by forming housings for vibration-producing components to couple to information handling system  10  with integrated mounts of dampening material. Some examples of plastic materials for the formation of the rigid and flexible portions of housing  26  include: Polyone Synprene IT37-031 and APA Alcryn 2060 BK.  
         [0027]    Referring now to FIGS. 3 a,    3   b,  and  3   c,  a blow-up side view of an assembly of a fan housing  26  to an information handling system  10  illustrates the reduced complexity for information handling system assembly provided by dampening material integrated at the mounting point  34  of housing  26 . The cooling fan assembly supported by housing  26  couples to an opening  38  of information handling system  10  in essentially a single step. FIG. 3 a  depicts an attachment point  36  formed as a male member that is inserted into a female opening  38  of information handling system  10 . Attachment point  36  has a nipple shape and a securing ring  40  having a diameter that slightly exceeds the diameter of opening  38 . The nipple end of attachment point  36  is pulled through opening  38 , such as with pliers, to force securing ring  40  through opening  38 , thus securing housing  26  to information handling system  10 . Attachment point  36  is formed with an elastic material to absorb vibration and also to provide for flexibility of ring  40  to pass through opening  38 .  
         [0028]    [0028]FIGS. 3 b  and  3   c  depict alternative attachment points  36  and alternative locations for the dampening material proximate the mounting point  34 . FIG. 3 b  depicts a screw attachment point  36  which is held in place by a nut  42 . Screw attachment point  36  is formed with rigid material and a dampening section  44  is disposed between screw attachment point  36  and housing  26  so that dampening material secures housing  26  to information handling system  10 . FIG. 3 c  depicts an indented attachment point  36  that engages flexible snaps  46  associated with information handling system  10 . A dampening section  44  dampens vibration transfer from housing  26 , although indented attachment point  36  may also be formed from dampening material. FIGS. 3 b  and  3   c  illustrate that a variety of attachment points may be used to secure housing  26  to information handling system  10  with the attachment points formed from flexible material or proximate flexible material to dampen vibrations.  
         [0029]    With vibration dampening for cooling fan  14  provided by dampening portions of mounting points  34  integrated with housing  26 , the need to couple cooling fan housing  26  to information handling system  10  with separate vibration dampening devices, such as elastic rubber grommets, is substantially reduced or eliminated. Thus, the assembly process for installing a cooling fan assembly into an information handling system  10  involves a reduced number of steps, reducing labor costs and part inventory management needs. Further, the use of two-shot molding to form a component housing places the vibration dampening in a single part tool to reduce the complexity of designing information handling system housing chassis component mounting. This results in reduced lead time and cost of vibration dampening solutions with vibration isolation located in the component housing, not the information handling system housing chassis.  
         [0030]    Although the present invention has been described in detail, it should be understood that various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the invention as defined by the appended claims.