Abstract:
A bracket is provided for mounting daughter cards to a computer motherboard. The bracket is connectable to the chassis of the computer and has support slots that cooperate with connectors on the motherboard to secure the daughter cards. The bracket supports a fan for cooling the daughter cards. The fan gathers the cooling air from a plenum incorporated in the bracket. A grill incorporated in the bracket directs the cooling air over the daughter cards.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. patent application Ser. No. 09/371,135, filed Aug. 10, 1999, now abandoned. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to computers and, more particularly, to a daughter card support and fan cooler for use within a computer housing. 
     BACKGROUND OF THE INVENTION 
     Personal computers are widely used in modern society. Personal computers generally consist of a cabinet containing a single chip-based system processor, and associated volatile and non-volatile memory. Also contained within the cabinet may be one or more diskette drives, and fixed disc storage. Peripheral equipment attached to the computer include a display monitor, a keyboard, a printer, etc. Typically, mounted within the cabinet of the computer is a planar, printed circuit motherboard that is used to electrically connect the various components of the computer together. 
     In addition, a large number and variety of printed circuit add-on daughter cards have been developed for providing enhanced operation and additional features for personal computers. Many add-on cards have become standardized in their dimensions and connectors and are suitable for plug-in attachment to the motherboard of a personal computer. Often, the motherboard connectors to which the daughter cards connect are mounted directly on the top surface of the motherboard so that the planar daughter cards plug into the motherboard perpendicular to the plane of the motherboard. This configuration allows the motherboard configuration to be more compact, thereby shortening the circuit path in the apparatus and allowing the system to operate at greater speed. 
     A number of auxiliary structures and techniques have been developed for permitting industry standard add on cards to be plugged into the motherboards. Some of these auxiliary structures have resulted in bulky and space consuming housings. In addition, extrinsic securing devices such as screws and bolts are often used to secure the daughter card within the housing. These mounting systems are cumbersome to use and require time and effort to assemble and disassemble. 
     The cabinet of a personal computer protects the operating components of the computer and shields against undesirable emission of electro-magnetic energy. There are many heat generating components enclosed in the cabinet of a computer. Unfortunately, most of the very large scale integrated circuits (VLSI chips) used in personal computers are designed to operate over certain temperature ranges. Consequently, it is necessary to provide for cooling of the components of the personal computer to assure proper operation. 
     Convection is used to cool the components of personal computers. Convection cooling often includes a forced air flow through the computer enclosure. Typically, a single fan is mounted adjacent to the power supply for the computer, producing a flow of air through the enclosure and particularly through the power supply, which is often the principle heat source within the enclosure. As discussed above, however, personal computers are routinely upgraded with add-on cards for various functions. Moreover, disk drives and VLSI chips may be upgraded. With such additions and upgrades, however, comes increased thermal load. This increased thermal load may overwhelm the existing cooling system of the personal computer. 
     Some personal computers have no provision for the addition of increased cooling in the computer cabinet. Others have space for a second cooling fan, but this often requires a complicated bracket that must be attached to the chassis of the computer with fasteners. Often there is no provision for producing cooling air directly to the added or upgraded components or conversely, cumbersome add-on ducts are needed. 
     What is required, then, is an easily employed bracket that supports add-on daughter cards and simultaneously provides the additional cooling required for these daughter cards. 
     SUMMARY OF THE INVENTION 
     The present invention provides a method and apparatus for supporting and cooling daughter cards of computers. In accordance with the present invention a bracket is provided which is detachably mounted in a computer. The bracket has a body and defines supports for a plurality of daughter cards. These supports may consist of slots. A cooling fan is attached to the body and its cooling air is directed over any daughter cards held by the slots. The fan may be detachably mounted to the body of the bracket with snap fittings. Similarly, the bracket may be detachably mounted to a chassis of a computer with snap fittings. The slots of the bracket align With electrical connectors of the motherboard of the computer in order to enable a secure electrical and mechanical connection of daughter cards to the computer. 
     In another aspect of the invention the supporting and cooling bracket consists of a platform defining a grill supported by end walls and side walls. The bracket defines a support for a daughter card and has a cooling fan detachably mounted to it and directed towards the daughter cards. Cooling air is collected by the plenum of the bracket. 
     In another aspect of the invention, an upgrade kit for a computer consists of an add-on daughter card and a bracket that defines a support for the daughter card and to which a cooling fan is attached. 
     The above and other advantages and features of the invention will be more readily understood from the following detailed description of the invention which is provided in connection with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an illustration showing a perspective view of a daughter card support and cooler bracket within a computer housing. 
     FIG. 2 is an elevation view of a daughter card support and cooler bracket. 
     FIG. 3 is a sectional plan view of the nominal front of a daughter card support and cooler bracket. 
     FIG. 4 is a plan view of the nominal right side of a daughter card support and cooler bracket. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A preferred embodiment of the invention is illustrated in FIG. 1. A computer  1  has a chassis  2  including a rectangular planar base  4  and a rectangular end wall  6  perpendicularly attached to one end  7  of the base  4 . The computer also includes a housing, at least one microprocessor chip, a main memory, input/output systems and the like as would be apparent to those skilled in the art. The specific electrical and mechanical details of the computer system and its components are well known in the art and will not be further described. Mounted to the base  4 , in a manner well known in the art, is a motherboard  8 . A number of linear multi-pin connectors are mounted to the motherboard parallel to each other in such a fashion that a line drawn through the major dimension of each multi-pin connector is perpendicular to end wall  6 . 
     The multi-pin connectors  10  are provided on the motherboard  8  for the purpose of adding various add-on daughter cards  12 , one of which is shown in FIG.  1 . These multi-pin connectors are electrically connected to the motherboard in order to provide access by the add-on daughter cards to the power, control signals and data lines of the main bus of the computer in a manner well known in the art. A card support and cooler bracket  100  is attached to the end wall  6 . Mounted within a plenum  102  of the bracket  100  is a cooling fan  104 . Protruding from the bracket  100  are a number of card-mounting lugs  106 A- 106 F that define between them a number of card-mounting slots  108 . The card-mounting lugs  106  are arranged in such a manner that the card-mounting slots  108  are in line with a plane that runs through the major dimension of the multi-pin connectors  10  and is perpendicular to both the base  4  and end wall  6 . 
     The industry standard daughter card  12  consists of a rectangular printed circuit board  24  to which the various components required to perform the function of the daughter card are mounted. Along one edge  26  of the daughter card  24  is attached a multi pin edge connector  28  that is electrically connected to the components of the daughter card  12 . Thus, the daughter card  12  may be mounted to the motherboard  8  by placing it in the plane through the appropriate multi-pin connector  10  and perpendicular to the base  4  and end wall  6  of the computer, sliding a second edge  30  of the daughter card  12  in the appropriate card-mounting slot  108  and connecting the multipin edge connector  28  of the daughter card  12  to the appropriate multi-pin connector  10  of the motherboard  8 . This arrangement provides both a reliable electrical and mechanical connection of the daughter card  12  to the motherboard  8  and within the computer  1  itself. Those skilled in the art will appreciate that the invention can also be employed with full size and half size as well as nonstandard daughter cards, as well as with any planar computer components which may be mounted on a motherboard  8 . 
     The cooling fan  104  is electrically connected to the computer  1 , through an electrical snap connector or other means well known in the art, in such a manner that the fan  104  operates when the computer  1  is turned on. In operation the fan  104  collects air from the plenum  102  of the bracket  100 . The air is drawn from outside the computer through vents and grills in the cabinet of the computer, for example in end wall  6 , as is well known in the art. Some air is drawn through two large vents  110  of the bracket  100 . The fan expels the cooling air through the grill  112  of the bracket along both surfaces of each daughter card  12  mounted to the bracket  100 . The forced air efficiently cools the daughter cards  12  and provides additional general cooling to the computer  1  once it has passed the daughter cards  12 . Depending on the computer applications involved, provision can be made for multiple card support and cooler brackets as required for mounting and cooling the add-on daughter cards  12  expected to be used. For instance, a second bracket could be mounted on end wall  6  next to bracket  100 , and another set of daughter cards could be mounted parallel to daughter card  12  shown in FIG.  1 . Bracket  100 , fan  104 , and/or daughter cards  12  also can be packaged together and supplied as upgrade kits for application to computers by original equipment manufacturers, computer remanufacturers, computer tradesmen, and end users. 
     Depending on the computer applications involved, provision can be made for multiple card support and cooler brackets as required for mounting and cooling the add-on daughter cards  12  expected to be used. For instance, a second bracket could be mounted on end wall  6  next to bracket  100 , and another set of daughter cards could be mounted parallel to daughter card  12  shown in FIG.  1 . Bracket  100 , fan  104 , and/or daughter cards  12  also can be packaged together and supplied as upgrade kits for application to computers by original equipment manufacturers, computer remanufacturers, computer tradesmen, and end users. 
     Bracket  100  is illustrated in more detail in FIG. 2 and 3. Bracket  100  can be attached within a computer in different orientations, thus the illustration of FIG. 3 shall be referred to as a plan view and the illustration of FIG. 2 shall be referred to as a front elevation view for convenience only. As best shown in FIG. 2, a planar, rectangular platform  114  has a plurality of cut-outs  116  arranged in a manner that the platform creates a lattice-like grill  112 . At each end  118 ,  118 ′ of the platform  114  are located planar, rectangular end walls  120 ,  120 ′, best shown in FIG. 3, that are located flush with the ends  118 ,  118 ′ of the platform  114  and perpendicular to the plane of the platform  114 . Inner walls  122 ,  122 ′ are located parallel to the end walls  120 ,  120 ′ near the ends  118 ,  118 ′ of the platform  114  leaving small spaces  123 ,  123 ′ between the end walls  120 ,  120 ′ and the inner walls  122 ,  122 ′. Two planar side walls  124 ,  124 ′ ( 124 ′ not shown in section view of FIG. 3) are located flush with the edges  126 ,  127  of the platform  114 , each side wall  124  being joined with one end of each of the end walls  120 ,  120 ′ and each of the inner walls  122 ,  122 ′. The entire bracket is preferably molded, extruded or otherwise formed as a single integral unit from low cost, durable polymers known in the art. 
     A large, substantially semi-circular vent  110  is formed in each side wall  124  between the inner end walls  122 ,  122 ′ and opposite the platform  114 . A plenum  102  is formed by the platform  114 , inner walls  122 ,  122 ′ and side walls  124 ,  124 ′. The side walls  124 ,  124 ′, end walls  120 ,  120 ′ and inner walls  122 ,  122 ′ form two box-like supports  128 ,  128 ′, one each at ends  118 ,  118 ′ of the platform  114 . Along first edge  126  and at each end  118 ,  118 ′ of the platform  114  opposite the supports  128 ,  128 ′ are two end lugs  106 A,  106 F in the form of narrow box like protrusions. In between the two end lugs  106 A,  106 F are central inner lugs  106 C,  106 D and distal inner lugs  106 B,  106 E. A series of five slots  108  are formed by lugs  106 A- 106 F. The two central inner lugs  106 C,  106 D each have a cut-out  134  in them accessing the plenum  102 . The lugs of the invention may be evenly spaced and rectilinear as shown in FIG.  1 . Alternatively, they may be unevenly spaced to accommodate various motherboard or daughter card configurations and/or may have chamfered corners to facilitate daughter card insertion in slots  108 , as shown in FIG.  2 . 
     Tabs  136 ,  136 ′ project from the outside corners  138 ,  138 ′ of each corner cut-out  140 ,  140 ′ of the platform  114 . Each tab  136 ,  136 ′ has a first cylindrical member  142 ,  142 ′ oriented perpendicular to the platform  114 . Within the two distal inner lugs  106 B,  106 E, second cylindrical members  144 ,  144 ′ depend from closed surfaces  146 ,  146 ′. Each second cylindrical member  144 ,  144 ′ is also perpendicular to the platform. Each of the first cylindrical members  142 ,  142 ′ and second cylindrical members  144 ,  144 ′ has a bayonet snap fitting  148 . 
     At the foot  152  of end wall  120  are located two register posts  154  in the shape of an L. At the foot  152 ′ of end wall  120 ′ are molded two resilient, deflectable, rectangular snap fittings  158  consisting of a rectangular tab  160  attached at one end  162  of a slot  164  formed in the wall  120 , as shown in FIG. 4. A projection  166  of the tab  160  protrudes past the surface of end wall  120 ′ and has a shoulder  168 . Alternatively, two additional snap fittings like snap fittings  158  can be located on end wall  120  instead of register posts  154  for engaging the chassis  2 . Accordingly, in one embodiment of the invention shown in FIG. 3, the end walls  120  and  120 ′ of the bracket  100  connect to end wall  6  of the chassis (FIG. 1) with the register posts  154  and rectangular snap fittings  158 . The inner walls  122  and  122 ′ are disposed inwardly from the end walls  120  and  120 ′ and define the plenum  102 . The fan  104  is positioned within the plenum  102  and is secured in place by the barbed ends of the inner walls  122  and  122 ′. The barbed ends of the inner walls  122  and  122 ′ also provide an offset between the chassis end wall  6  and the end of the fan closest to the chassis end wall  6 . The generally semi-circular vents  110  in opposite sidewalls  124  of the bracket  100  allow air to be drawn into the plenum  102  and through the fan  104  via the gap between the fan  104  and the chassis end wall  6 . 
     An advantage of His arrangement is that the vents  110  allow the fan to draw air from within the chassis into the plenum  102 , mix the air drawn through the vents  110  with air drawn directly into the plenum  102  through grills in the computer chassis, and propel the air over the daughter cards for cooling. 
     In operation, a standard, 60 mm cooling fan  104 , having four recesses opposite bayonet snap fittings  148 , is easily snapped into the plenum  102  of the bracket  100 . Those skilled in the art will be familiar with this and other types of snap-together arrangements, as well as other fasteners for this task such as screws and the like. The bracket  100  is then easily assembled onto the end wall  6  of the chassis  2 . Two sets of two slots  172 ,  173  are located in end wall  6  and spaced to engage the register posts  154  and the snap fit projections  166  of bracket  100 . Assembly is accomplished by placing the L shaped register posts  154  in slots  172  and rotating the bracket  100  about the register posts  154  until the snap fit projections  166  snap into the second set of slots  173 . Assembly is completed by snapping together the electrical connector of the fan to the computer. 
     Daughter cards  12  are inserted by engaging a second edge  30  of the daughter card  12  in a slot  108  of the bracket  100  and connecting the multi-pin edge connector  28  of the daughter card  12  into the multi-pin connector  10  of the motherboard  8 . The combination of the connectors  10 ,  28  and the slot  108  provides a reliable, electrical connection and stable physical support of the daughter card  12 , and easy assembly and disassembly. During operation of the computer  1 , the fan  104  operates to draw air from the plenum  102  and force it between and around the daughter cards  12  to cool them. From there the air dissipates throughout the cabinet of the computer  1  for additional cooling of the computer  1 . 
     The invention provides a method and apparatus for simply and inexpensively adding support and cooling for add-on daughter cards used in computers. 
     Variations of the embodiment will be readily apparent to those skilled in the art. For example, the invention may be employed with the bracket mounted to the base  4  of the chassis  2 , instead of the end wall  6 . Accordingly, it is to be understood that although the present invention has been described with reference to a preferred embodiment, various modifications may be made to the structures and steps presented herein by those skilled in the art without departing from the spirit or scope of the invention which is defined in the claims appended hereto.