Abstract:
There is described a housing for mounting electronic boards therein, the housing having at least one horizontally positioned plane, adapted for allowing a plurality of electronic circuits to be connected thereto. The plane is arranged to allow air to flow between opposing walls of the housing without causing the air to traverse bends. The electronic circuits may be positioned on both the top and bottom surface of the horizontal plane. In one embodiment, the housing is a computer.

Description:
DESCRIPTION OF RELATED ART  
       [0001]     It has become common to arrange electrical equipment housings, such as computers and the like, with a back-plane having thereon a plurality of connectors. These connectors are adapted for mating with electrical equipment, such as PC boards, which in turn are used to control the equipment. When the system is in operation, the electrical components generate heat that must be removed in order to prevent system failures. The ability to remove heat is a gating factor as to the number of electrical components that can be positioned within a given size of housing.  
         [0002]     It has also become common to force air through electrical equipment housings to remove heat from the equipment. Increasing air flow is a major factor in increasing heat removal. However, there is a practical limit to the air flow capacity of a given housing. Because the back-plane upon which the equipment is mounted is positioned in the air flow path, the back-plane itself impedes air flow through the housing.  
       BRIEF SUMMARY OF THE INVENTION  
       [0003]     In one embodiment, there is described a housing for mounting electronic boards therein, the housing having at least one horizontally positioned plane, adapted for allowing a plurality of electronic circuits to be connected thereto. The plane is arranged to allow air to flow between opposing walls of the housing without causing the air to traverse bends. The electronic circuits may be positioned on both the top and bottom surface of the horizontal plane. In one embodiment, the housing is a computer. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0004]      FIG. 1  shows a perspective view of one embodiment of an electrical equipment housing;  
         [0005]      FIG. 2  shows a side sectional view of the housing taken along line  1 B- 1 B of  FIG. 1 ;  
         [0006]      FIG. 3  is one embodiment of an electronic board;  
         [0007]      FIG. 4  shows a side view of the housing of  FIG. 1  just prior to the insertion of a first electronic board; and  
         [0008]      FIG. 5  shows one embodiment of multiple electronic boards inserted on the top and bottom surfaces of a horizontally positioned mounting surface. 
     
    
     DETAILED DESCRIPTION  
       [0009]      FIG. 1  shows one embodiment of housing  10  in which electrical components, such as electronic boards  30  are positioned. Housing  10  has front vertical surface  101  having contained therein, if desired, an opening for the insertion of the electronic boards, such as electronic boards  30 - 1 U to  30 -NL. In the embodiment shown, horizontal mounting structure  12  has mounted thereon connectors  13  adapted for receiving contacts  33  (shown in  FIG. 3 ) of the electronic boards. In  FIG. 1 , the electronics boards are plug-in circuit boards of a computer.  
         [0010]     In the embodiment shown, mounting structure  12  (which is the mounting plane for the plug-in boards) has connectors  13  mounted on both its top and bottom surfaces. Note that in other embodiments the connectors may be mounted only on one surface and, if desired, there may be multiple mounting structures (not shown) stacked within the housing. It is contemplated that those surfaces would all be horizontal, but some could, if desired, be vertical. As will be discussed, air can flow between front vertical surface  101  and back vertical surface  103  such that the air traverses the area essentially parallel to mounting surface  12  and in-line with the electronic boards mounted to surface  12 . As shown, the electronic boards are mounted perpendicular to mounting surface  12 , but could be mounted at any angle thereto. While plug-in wiring boards are shown, any type of component could be attached to surface  12  using, for example, a pigtail electrical connection and a mechanical support.  
         [0011]     One system that is particularly adaptable for the arrangements discussed here is a computer system wherein each plug-in board is a blade of the system, such blade typically contains all of the elements of a traditional computer, namely processors, memory, and I/O. The air flows along the plane of mounting surface  12  and in-line with the electronic boards, the air need not bend around either the mounting surface or the components mounted on the electronic boards. This moving air is free to impact components mounted on both sides of the mounted electronic boards and thus can carry heat away from both sides of the boards.  
         [0012]     Fan  102 , shown mounted in the back vertical surface opposite the front vertical surface, causes air to flow between the front and back vertical surfaces. The fan could be designed to blow air in or suck air out as desired. Also, as will be discussed, the fan (or a number of fans) could be mounted internally within housing  10  as well. Also, in some situations, the fan could be eliminated, allowing natural convection to carry heat away from the components.  
         [0013]     As shown in  FIG. 1 , any number of plug-in boards  30  may be mounted on surface  12 . In this embodiment, boards  30 - 1 U to  30 -NU are shown plugged into connectors on the top surface of structure  12  while boards  30 - 1 L to  30 -NL are shown plugged into connectors on the bottom (or underside) of surface  12 .  
         [0014]      FIG. 2  shows a side sectional view of housing  10  taken along section line  1 B- 1 B of  FIG. 1 . Electronic board  30 -NU is shown plugged into connector  13 -NU mounted on the top surface of structure  12  and electronic board  30 -NL is shown plugged into connector  13 -NL mounted on the bottom surface of structure  12 . Air  104 , controlled in part by fan  102 , is shown flowing from back vertical panel  103  and out front vertical panel  101 . As can be seen, this air flows essentially parallel to structure  12  without traversing around bends. This air will flow easily past all of the electronic components mounted on both the top and, if desired, bottom surfaces of structure  12  without mechanical hindrance.  
         [0015]     Electronic boards  30  may be inserted into the various connectors  13  for example, by opening a door (not shown) in the vertical panel or by removing the panel. The board to be inserted is first positioned over (or under) the desired connector and then pressed downward (or upward) for insertion into the connector. Once in place, friction (and/or locking mechanism) between the connector and the pins of the electronic board maintains the board in mating relationship. Alternatively, a bracket (not shown) can be used to hold the board and the connector together, if desired.  
         [0016]      FIG. 3  shows one embodiment  30  of an electronic board having contacts  33  for mating with connector  13 . Mounted on board  30  are components  34 . Not shown are components mounted within or on the other side of board  30 . Fan  35  is shown and maybe optionally mounted on one or more boards as desired. Fan  35  may be used in conjunction with, or as a substitute for, fan  102  ( FIG. 1 ). The system could be designed such that each board (or each group of boards) contains its own fan so that as the system grows (i.e., more and more boards connected within housing  10 ), the air moving capability would also grow in direct proportion to the number of connected boards.  
         [0017]      FIG. 4  shows a side view of housing  40  just before board  30 - 1 U is inserted downward into connector  13  mounted on the top surface of horizontal structure  12 . Board  30 - 1 U is positioned over connector  13  by insertion through an opening in front vertical surface  101  as previously discussed. Mounting structure  42  is the same as structure  12  (plane  3 ) except that both the top and bottom surfaces of structure  42  contain dual rows of connectors for higher density. Also, structure  42  of housing  40  has fan  41  positioned thereon. Housing  40  is shown with communication devices  111 , data storage devices  112  and power supply  110 , one or more of which devices would typically be found within a computer. Other such devices can also be contained within the housing, if desired. In some cases, these devices could also be plugged into a connector positioned on structure  42 .  
         [0018]      FIG. 5  shows housing  40  having several plug-in boards mounted therein in dual upper and dual lower rows. Boards  30 -NUF to  30 -NUB are shown on the top surface of structure  12  while boards  30 -NLF to  30  NLB are shown plugged upward onto the bottom surface. Fan  41  draws air  301  in through vents in front surface  101  and causes the air to flow past all of the boards plugged into connectors on the bottom surface of mounting structure  42 . The air is forced out of vents in vertical back surface  103 . Air flow on the top of surface  42  could be controlled in a similar fashion, or could be controlled by a fan in one or more of the vertical surfaces or by fans connected to one or more electrical boards  30 . This then allows for dual airflow control.  
         [0019]     While, in theory, the air could move in other directions (for example, air drawn in through the front and rear and forced out through the top and bottom) through housing  40 , this is not practical because the housings are often mounted into a system with their respective sides in close proximity to each other.