Patent Publication Number: US-6909611-B2

Title: Rack mountable computer component and method of making same

Description:
RELATED APPLICATION 
     This application claims priority to the following U.S. provisional applications: Ser. No. 60/384,996, titled “Rack Mountable Computer Component and Method of Making Same”, filed May 31, 2002 now abandoned; Ser. No. 60/384,987, titled “Rack Mountable Computer Component Cooling Method and Device”, filed May 31, 2002 now abandoned; Ser. No. 60/384,986 filed on May 31, 2002, now abandoned titled “Rack Mountable Computer Component Fan Cooling Arrangement and Method”, and Ser. No. 60/385,005 filed on May 31, 2002, now adandoned, titled “Rack Mountable Computer Component Power Distribution Unit and Method”, which are each hereby incorporated by reference in their entirety. 
     This application relates to the following U.S. non-provisional patent applications: Ser. No. 10/448,691, titled “Rack Mountable Computer Component Cooling Method and Device,” filed May 28, 2003; Ser. No. 10/290,676 titled “Rack Mountable Computer Fan Cooling Arrangement Method;” and Ser. No. 10/448,508 titled “Rack Mountable Component Power Distribution Unit and Method,” which are each hereby incorporated by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates, in general to a new and improved method computer components adapted for rack mounting. It more particularly relates to such a method and apparatus for computer components adapted to be mounted in a compact configuration. 
     2. Related Art 
     There have been a variety of different types and kinds of methods and systems for mounting computer components. For example, reference may be made to the following United States patents: 
     
       
         
           
               
               
               
               
             
               
                   
                   
               
               
                   
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     As a result of having available a large number of different types and kinds of mounting techniques, a standard has been adopted for mounting computer components in racks according to a certain modular configuration. In this regard, computer components such as computer processor units, and the like, are mounted one above the other in a column in standard size rack configurations. The standard is referred to as the EIA-310-D Standard, as clarified by the Server Rack Specification (SSI). 
     The housing for each computer device must have a certain height dimensions according to the Standard. The height dimension must be a multiple of a standard unit “U”. Thus, there can be computer components which are 1 “U” (standard unit) high or multiples thereof. Thus, there can also be standard rack mountable computer components which are 1 U, 2 U, 3 U, 4 U and so on. 
     Thus, according to the conventional currently-used standard, racks are provided for storage of computer components in tightly spaced, densely packed horizontal dispositions, and each computer component mounted in the rack is suitably dimensioned in multiples of standard unit U. The racks are movably mounted on casters or the like so that they can be readily positioned in, for example, a computer room having a tightly controlled air conditioning system to ensure proper cooling of the computer equipment. 
     It is highly desirable to configure the computer components in the rack in a compact and highly dense manner for some applications. Thus, it has been important for many applications to position in the computer room or other assigned space as many computer components as possible. 
     In order to compactly mount the computer components on the rack in a high density manner, they are closely positioned one above the other in a column. The data and power cables are positioned in a back plane area or space within the rack. 
     For cooling purposes, various techniques are employed. For example, individual fans have been mounted within the housing of each computer component. The interiors of the housing have been exhausted to a fan exhaust plenum chamber often times constructed within the rack at one side thereof. 
     Such conventional rack mounted systems have several drawbacks. The individual fans mounted in each component are expensive, and time-consuming to replace in case of malfunctions. Also, the back plane space and fan exhaust plenum chamber are wasted space in that they occupy spaces which could otherwise be filled with computer components. 
     Additionally, in order to assemble the rack mounted system for installation at the site, each component must be installed in place within the rack, and then the cabling for each unit is routed within the rack at its back plane space. Such an operation is time consuming, and therefore expensive since highly trained personnel are required to do such an installation. Furthermore, once installed, in order to replace a malfunctioning computer component, the entire system, or at least a substantial portion thereof, must be shut down so that the malfunctioning unit can be disassembled, and a replacement unit installed and reconnected electrically. This, too, is time consuming and expensive. 
     In conventional rack mounted computer components, since the cabling for the computer components are often times mounted at the back portion of the rack, the principal circuit boards such as mother boards are mounted at the rear portion of the computer component housing for ease of attachment to the cabling at the rear of the rack. Such a configuration of the circuit boards within the computer component housing is less than desirable for some applications. For example, a user may wish to connect test components such as a keyboard and monitor to a given one of the rack mounted computer components. It is difficult to accomplish ordinarily because the access to the mother board is disposed at the rear of the housing. In this regard, access to a given computer component must be made at the rear of the rack where a large number of cables are present and thus block access to the computer module. Additionally, by mounting the mother board at the rear of the component housing, it is frequently difficult and expensive to mount fans and baffles to direct air entering the front of the housing and being exhausted from the rear thereof. 
     Therefore, it would be highly desirable to have a new and improved computer component construction which is relatively easy for the user to access individual components and which is relatively efficient and effective to ventilate for cooling purposes. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The following is a brief description of the drawings: 
         FIG. 1  is a pictorial view of a rack-mounted system showing the front, left side and top thereof, which is constructed in accordance with an embodiment of the present invention; 
         FIG. 2  is a front elevational view of the rack-mounted system of  FIG. 1 ; 
         FIG. 3  is a left side elevational view of the rack-mounted system of  FIG. 1 ; 
         FIG. 4  is a rear elevational view of the rack-mounted system of  FIG. 1 ; 
         FIG. 5  is a right side elevational view of the rack-mounted system of  FIG. 1 ; 
         FIG. 6  is a pictorial view of the rack-mounted system of  FIG. 1 , showing the rear, right side and top thereof; 
         FIG. 7  is a pictorial view of the housing of the rack-mounted system of  FIG. 1  without various components being mounted for illustration purposes; 
         FIG. 8  is a pictorial view of the housing of  FIG. 7  illustrating the process of installation of fan/LAN trays; 
         FIG. 9  is an enlarged scale pictorial view of one embodiment of a fan/LAN tray for the rack-mounted system of  FIG. 1 ; 
         FIG. 10  is a pictorial view of the housing of  FIG. 7  with the fan/LAN trays installed; 
         FIG. 11  is a pictorial view of the housing of  FIG. 7  illustrating the process of installation of blades; 
         FIG. 12  is a fragmentary, enlarged scale front elevational view of the rack-mounted system of  FIG. 1  illustrating the relative positioning of the fan/LAN trays and the blades; 
         FIG. 13  is a diagrammatic, right-side elevational view of the rack-mounted system of  FIG. 1  illustrating the configuration of the right-side cabling; 
         FIG. 14  is a bottom fragmentary pictorial view of the rack-mounted system of  FIG. 1  illustrating the cabling in the front and right portion of the control bay; 
         FIG. 15  is a diagrammatic, left-side elevational view of the rack-mounted system of  FIG. 1  illustrating the configuration of the left-side cabling; 
         FIG. 16  is a bottom fragmentary pictorial view of the rack-mounted system of  FIG. 1  illustrating the cabling in the rear and left portion of the control bay; 
         FIG. 17  is an enlarged scale, fragmentary pictorial view of one embodiment of a power distribution unit (PDU) for the rack-mounted system of  FIG. 1 ; 
         FIG. 18  is a front elevational view of the PDU shown in  FIG. 17 ; 
         FIG. 19  is a fragmentary top view of the PDU shown in  FIG. 17 ; 
         FIG. 20  is a rear elevational view of the PDU shown in  FIG. 17 ; 
         FIG. 21  is a diagrammatic view of the rack-mounted system of  FIG. 1  illustrating the flow of air therethrough; 
         FIG. 22  is a diagrammatic view of another embodiment of a rack-mounted system according to the present invention and illustrating the flow of air therethrough; 
         FIG. 23  is a diagrammatic view of yet another embodiment of a rack-mounted system according to the present invention and illustrating the flow of air therethrough; 
         FIG. 24  is a diagrammatic view of still another embodiment of a rack-mounted system according to the present invention and illustrating the flow of air therethrough; 
         FIG. 25  is an enlarged scale top view of one embodiment of a blade of the rack-mounted system of  FIG. 1 ; and 
         FIG. 26  is a left side elevational view of the blade of FIG.  1 . 
     
    
    
     DESCRIPTION OF CERTAIN EMBODIMENTS OF THE INVENTION 
     According to at least one of the disclosed embodiments of the present invention, there is disclosed a rack mountable computer component which is in the form of an open computer component or blade construction which is adapted to be mounted in a generally upright or vertical disposition within a rack. The operative components such as mother boards are mounted at the front of the component or blade to permit access by the user thereto. The operative components are cooled by vertical air flow relative to the mounted blade to facilitate cooling thereof. 
     According to disclosed embodiments of the invention, the component construction includes a support having the active components mounted on at least one side thereof and being adapted to be supported in a generally upright configuration. A front panel extends transversely to a front edge portion of the support and an outlet disposed thereat is connected to at least one of the operative components. An electrical power inlet is mounted at a rear edge portion of the support to receive electrical power for the operative components. 
     As disclosed herein, the support includes a cut-out portion, and the power inlet is disposed near the cut-out portion. The segment is generally rectangular in shape and is substantially rigid. Also, as disclosed herein, at least one of the operative components such as a mother board is disposed near the front edge portion of the support and is connected electrically to the outlet. As further disclosed herein, a cable is connected electrically to the outlet on the front panel to convey electrical information from the operative components. 
     In accordance with the disclosed embodiments of the invention, one edge of the front panel is disposed at an edge of the support to form an L-shaped configuration. Thus, the transverse front panel and the supports are so constructed and arranged that the resulting component construction can be arranged in a generally upright side-by-side configuration with like units in a close abutting relationship. Thus, the front panels of the like components provide a substantially continuous upright wall, and yet the operative components are mounted on the upright support in an open configuration. In this manner, the component constructions can be disposed in a vertical flow path for air moving past the active components mounted on this upright support. 
     General System Description 
     Referring now to the drawings, and more particularly to  FIGS. 1 through 21  and  29  and  30 , there is illustrated one embodiment of a rack mounted system  10  according to the present disclosed embodiments of the invention. The rack mounted system  10  includes a rack housing  12  configured generally as a rectangular box having a plurality of vertical bays  14 . The embodiment illustrated in the drawings includes three vertically spaced-apart bays  14 . 
     Each bay  14  is divided into a front bay portion  16  and a rear bay portion  18  by an intermediate transversely-extending horizontal divider  19 . The intermediate divider  19  is most clearly illustrated in FIG.  7 . The bays  14  are formed in the rack housing  12  in a vertical manner one above the other. In a bottom portion of the rack housing  12 , a control bay  21  is provided to house various controlled components, as hereinafter described in greater detail. 
     The rack housing  12  further includes a fan/LAN tray slot  23  above each bay  14 . Each fan/LAN tray slot is configured to accommodate a fan/LAN tray such as tray  27 . 
     The embodiment illustrated in the drawings provides a control bay  21  ( FIG. 7 ) having a bottom opening  25  ( FIG. 7 ) for facilitating air flow to receive vertically moving air flow from a vent opening  26  in a floor  28  and vertically through the system  10  as assisted by the fan/LAN trays. At the top of the rack housing  12 , an apertured top panel  26  ( FIG. 1 ) is provided to permit venting of the vertically moving air flow from the system  10 . 
     At the top portion of each bay  14 , in the intermediate region between the front bay portion  16  and the rear bay portion  18 , as best seen in  FIGS. 1 ,  5 ,  6  and  8 , a power distribution unit (PDU)  29  is provided to supply electricity to various components mounted in the rack mounted system. Each bay is adapted to accommodate a plurality of computer components in the form of open structure computer components or blades, such as blade  32  (FIG.  1 ), in each of the front bay portions  16  and the rear bay portions  18 . In the embodiment illustrated in the figures, eleven blades may be accommodated in each of the front bay and rear bay portions in a generally upright disposition. Thus, in the illustrated embodiment, the system  10  accommodates  66  computer components in a densely compact, closely spaced configuration. 
     The bottom control bay  21  is adapted to accommodate various control components. These control components may include a circuit breaker junction box  34 , as most clearly illustrated in FIG.  6 . The circuit breaker junction box  34  is electrically connected to each PDU. As shown in  FIG. 4 , a switch module  36  is also provided in the control bay  21 . The switch module  36  is adapted to control communication between the various blades, such as blade  32 , and a network, such as a local area network, wide area network, or a public network, such as the internet. Further, the control bay  21  accommodates an air intake fan module  38  ( FIGS. 1 and 5 ) for facilitating intake of air through the bottom opening  25  and facilitating vertical air flow through the blades and the bays  14  and out the apertured top panel  26 . 
     The embodiment of the rack system  10  illustrated in the figures includes four casters  41  for rollably supporting the system on the floor  26  ( FIG. 5 ) for easy portability of the rack system  10 . Other embodiments of the rack system according to the present invention may be floor mounted, thereby including legs or skids in place of the casters for direct mounting to the floor. 
     Referring now to  FIGS. 8 and 9 , the fan/LAN tray  27  and its installation into the rack housing  12  will be described in further detail.  FIG. 9  illustrates one embodiment of a fan/LAN tray  27  for use with the rack system  10  illustrated in the drawings. The fan/LAN tray  27  includes eight suitable fans for facilitating vertical air flow. Although the embodiment illustrated in the drawings includes eight fans per tray, any suitable number of fans may be used. 
     In accordance with the disclosed embodiments of the present invention, the fan tray may also be divided into a plurality of separate trays or tray portions, each of which can be removed independently so that the remaining tray portion can continue to function. In this regard, it is contemplated that the LAN connections may be made in a unit or component separate from the fan tray or tray portions so that the tray or tray portion may be removed independently of the LAN component. In the front portion of the fan/LAN tray  27 , a series of LAN connector ports  45  ( FIGS. 1  and  9 ) is provided. In the embodiment illustrated in  FIG. 9 , each fan/LAN tray  27  includes  12  LAN connector ports  45 , the end one of which may be used for test purposes. While  12  LAN connectors are shown in the disclosed embodiment, it should be understood that any number of such connectors may be employed for a given application. Internal wiring leads (not shown) from each LAN connector port  45  extend to one of two signal connectors  47  ( FIG. 9 ) in the back portion of the fan/LAN tray  27 . In one embodiment, each signal connector  47  is a 50 pin signal connector, and is connected electrically to the switch module  36 . Further, each fan/LAN tray includes a AC power inlet  49  in the back portion for providing power to the fans. When installed, power may be supplied to the fans  43  through the AC power inlet  49  from the PDU  29 , as hereinafter described in greater detail. 
     For facilitating installation of the fan/LAN tray  27  into the fan/LAN tray slot  23  of the rack housing  12 , as shown in  FIG. 9 , guides  52  may be provided on the sides of each fan/LAN tray  27 . During the installation process, the guides, preferably nylon guides, may engage corresponding member on the sides of the fan/LAN tray slots  23 . Further, a locking mechanism may be provided in conjunction with the guides  52  for securing the fan/LAN tray  27  into the fan/LAN tray slot  23  to help support the fan/LAN tray. Once installed, each fan/LAN tray  27  occupies an area directly above either the front bay portion  16  or the rear bay portion  18 . Accordingly, a fan/LAN tray in the front and a fan/LAN tray in the rear may completely cover each bay  14  level. Thus, as illustrated most clearly in  FIG. 10 , a total of 6 fan/LAN trays  27 , in addition to the air intake fan module  38  may be provided in a three bay level rack mounted system  10  according to one embodiment of the present invention. 
     Computer Component Construction 
     Referring now to  FIGS. 11 ,  25  and  26 , the computer components or blades  32  and their installation into the rack housing  12  will now be described in greater detail. Each blade is provided with a pair of handles  54  projecting from the front face of a front panel. The front panel extends transversely to a rigid upright support or plate and is connected to the front edge of the support in an L-shaped configuration. The handles allow a user to easily manipulate the blade  32  to be grasped by the user to slide the blade into or out of its bay. Each blade  32  may include one or more mother boards  56 . In the embodiment illustrated in  FIGS. 25 and 26 , each blade  32  includes two mother boards  56   a,    56   b.  Those skilled in the art will appreciate that the number of mother boards included in each blade  32  may be varied according to design. The mother board may include heat sinks such as heat sinks  58  and  59  for facilitating the cooling of the mother boards. Further, each mother board is provided with random access memory (RAM)  61 . The amount of RAM  61  provided for each mother board may be varied as needed. A pair of power supply  63   a,    63   b  may be provided on the blade  32  for supplying power to their corresponding mother boards  56   a,    56   b.  Similarly, a pair of hard disks  64   a,    64   b  may also be provided on the blade  32 . 
     All of the components are mounted on one side of the rigid plate or support  64 , which is adapted to be supported vertically within its bay. Each blade  32  includes a cut-out corner portion or section  65  in its upper back portion. The cut-out portion  65  is sized to receive and accommodate the PDU  29  therebetween such that two opposing blades  32  and  32   a  (as shown in  FIG. 26 ) accommodate the PDU  29  almost completely. Thus, a substantially zero footprint is achieved for the PDU  29 . Each blade  32  is provided with an AC power inlet such as an inlet  67  at or near the cut-out portion  65 . Thus, when the blade  32  is installed into the rack housing  12 , the AC power inlet  67  engages electrically a corresponding AC connector such as a connector  76  ( FIG. 17 ) of the PDU  29 . 
     As most clearly illustrated in  FIG. 11 , the installation of the blade  32  may be achieved in a fast and efficient manner. The blade  32  is simply slid into either the front bay portion  16  or the rear bay portion  18  of a bay  14  of the rack housing  12 . Each blade  32  is slid back until its AC power inlet  67  engages a corresponding AC connector  76  on the PDU  29 . The intermediate dividers  19  serve as a back stop for the blades  32 . Each blade  32  is secured in its slot by four blade screws  69 , which attach the blade  32  to the rack housing  12 . 
     Once the blade  32  has been mounted onto the rack housing  12 , a short blade/LAN connector cable such as a cable  45  ( FIG. 12 ) or a cable  71  ( FIG. 1 ) provides electrical networking connection between the blade  32  and a network such as a local area network, wide area network or a public network such as the internet. In this regard, the mother boards are each mounted at the front of each blade, and thus access thereto is readily available at front outlets such as at outlet  73  (FIG.  12 ). Thus, a data connection can be made from the outlet  73 , through a short cable  45 , an inlet  77  of a PDU  29 , which is coupled to the switch module  36 . 
     Referring now to  FIGS. 17 through 20 , the power distribution unit  29  will now be described in greater detail. The PDU  29  supplies power from an external power source, through the circuit breaker junction box  34 , to the various blades  32  and the fan/LAN trays  27 . Each PDU  29  includes an elongated PDU body  74 , which preferably is formed of a two piece,  18  gauge steel chassis. Each of two sides of the PDU body  74  includes a series of female AC connectors  76 . In the embodiment illustrated in  FIGS. 17 through 20 , each side is provided with  12  female AC connectors  76 . The twelve connectors  76  correspond to eleven blades mounted in the front bay portion  16  and the rear bay portion  18  of each bay  14  and a fan/LAN tray  27 . The twelfth connector is for an AC power outlet on the front of the fan tray. 
     Thus,  12  female AC connectors  76  are provided on each of a front side and a rear side of the PDU body  74 . Each set of twelve female AC connectors  76  receives power through a pair of power cables  72 . In one embodiment, the power cable  72  is a  15  amp power cable with strained relief near its junction with the PDU body  74 . As described below, the power cables  72  are routed to the circuit breaker junction box  34  in the control bay  21 . The PDU body  74  may also include a series of mounting studs  78  for installation of the PDU body  74  to the rack housing  12 . 
     Referring now to  FIGS. 13 through 16 , the routing of the various power and LAN cables will now be described in detail. As illustrated most clearly in  FIG. 13 , the power cables  72  from the PDU&#39;s  29  at each bay level are directed along the right side of the rack housing  12  toward the front portion of the rack housing  12  and to the bottom, where they are connected electrically to the circuit breaker junction box  34 . Thus, in the embodiment illustrated in the drawings, six power cables  72  are connected to the circuit breaker junction box  34 , since there are two from each one of the three PDUs. A set of three cables generally indicated at  80  are each adapted to be coupled to a suitable source of AC power to supply power to the system  10 . 
     As also illustrated in  FIG. 13 , a set of six LAN cables  81  from the fan/LAN trays and PDUs are routed along the rear right side of the rack housing  12  to the switch module  36 . In the embodiment illustrated in the drawings, two LAN cables  81  extend from each PDU which, in turn, are connected electrically to a pair of fifty pin signal connectors  47 . Thus, six such cables  81  are directed along the right side of the rack housing  12 . Similarly, as most clearly shown in  FIG. 15 , six LAN cables  81  extend from the fan/LAN trays  27  and PDUs along the left front side of the rack housing  12 . These six cables  81  are also connected at their lower ends to the switch module  36 . 
     Once the rack system  10  is fully assembled with all the fan/LAN trays  27 , PDUs  29  and the blades  32  in place, a fully assembled and efficient rack mounted system is provided. In such a system, networking of the various components provided on the blades  32  is also performed efficiently. In the embodiment illustrated in the drawings, eleven blades are accommodated at each of the front bay portion  16  and the rear bay portion  18  at each bay  14 . Thus, in the embodiment illustrated,  66  such blades  32  may be accommodated. However, some of the slots may be occupied by master computer components or blades such as the master blades indicated at  32   a  in  FIGS. 4 and 6 . In the illustrated embodiment, two master blades  32   a  are provided in the bottom of the three blade bays directly above the switch module  36 . The master blades  32   a  are connected electrically directly to the switch module  36  via high speed connections (not shown) such as fiber optic connections. The master blades control the switch module  36  to switch communication between the various slave blades  32  and the master blades. Accordingly,  64  slave blades may be accommodated by the illustrated embodiment of the system. Each of the  64  slave blades may be hot swappable, for example, allowing replacement of the blades  32  without causing the shutting down of the system  10 . 
     Each fan/LAN tray  27  is provided with twelve LAN connector ports such as the port  45  (FIG.  1 ). Eleven of the 12 LAN connector ports  45  are adapted to permit communication between the various slave blades  32  and the switch module  36 . The twelfth LAN connector port  45  allows an external user to connect an-external device such as a laptop computer to the network. Further, each fan/LAN tray  27  is provided with a centrally disposed AC power outlet for connecting such an external device. 
     According to the disclosed embodiments of the present invention, and as indicated diagrammatically in  FIG. 21 , the system  10  illustrated in the figures provides efficient air flow to maintain a cool operating temperature for the various components mounted on the blades  32 . Air flow is directed from the bottom opening  25  by the air intake fan module  38  located in the control bay  21 . The air intake fan module  38  directs the air flow vertically through the various open structure blades  32  at each bay level  14 . The air flow is further facilitated by the fans  43  in each fan/LAN tray  27  to move the air in its upwardly directed path of travel. The air flow is directed out of the rack housing  12  through the apertured top panel  26 . 
       FIGS. 21 through 24  illustrate further embodiments of the present invention. As illustrated in  FIGS. 21 through 24 , the intake and exhaust of the air flow may be varied to accommodate various configurations as to the availability of air supply in the immediate environment. For example, in  FIG. 22 , an air intake fan module  38   a  draws air from a bottom opening  25   a,  similar to that illustrated in the embodiment shown in  FIGS. 1 through 21 . Air flow is directed vertically with the aid of fans  43   a  mounted on fan/LAN trays. However, unlike the previously described embodiment, in the embodiment illustrated in  FIG. 22 , the air flow is re-directed from a vertical path of travel at right angles to a horizontal path of travel out of the rack system  10   a  towards the rear of the rack housing. An air flow hood  85   a  facilitates the rearward re-direction of the air flow. 
       FIG. 23  illustrates yet another embodiment of the rack system according to the present invention. In this embodiment, an air intake fan module  38   b  draws air horizontally inwardly through an opening such as defined by a perforated plate  87   b  in the bottom front portion of the rack housing. The air flow is then re-directed upwardly with the aid of fans  43   b  mounted in fan/LAN trays. The air flow is directed vertically out of the top portion of rack system  10   b.    
     In the embodiment illustrated in  FIG. 24 , an air intake fan module  38   c  draws air horizontally through an opening such as defined by a perforated plate  87   c  in the front bottom portion of the rack housing. The air flow is re-directed vertically through this system with the aid of fans  43   c.  The air flow is re-directed at right angles to a horizontal path of travel out of the rack housing rearwardly at the top of the rack housing. The rearward redirection of the air flow is facilitated by an airflow hood  85   c.  It will be appreciated by those skilled in the art that other variations on the intake and exhaust of the air flow are possible in accordance with other embodiments of the present invention. 
     While particular embodiments of the present invention have been disclosed, it is to be understood that various different modifications and combinations are possible and are contemplated within the true spirit and scope of the appended claims. There is no intention, therefore, of limitations to the exact abstract and disclosure herein presented.