Patent Publication Number: US-6702124-B2

Title: Flat spring clip for tool-less slide installation

Description:
This application is related to application Ser. No. 10/003,278, titled “Dual Flat Springs for Tool-Less Slide Installation” filed Dec. 6, 2001. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to a slide assembly for slidably mounting a computer server to a rack and, more particularly, to a slide assembly for slidably mounting a computer server to a rack where the slide assembly includes a spring element mounted to front and back attachment brackets of the slide assembly to allow installation of the slide assembly to the rack columns without the need for tools. 
     2. Discussion of the Related Art 
     Certain computer systems, such as computer network systems, typically include many separate computer units or servers that are positioned and stacked relative to each other in a rack. The various computer servers in the system are electrically interconnected and provide various functions, such as storage, communications, calculations, etc. The rack includes a plurality of support columns, where each computer server is secured to opposing slide assemblies attached to the columns. The slide assemblies allow the server to be pulled away from the front of the rack so that each separate server can be serviced by technicians for various reasons, such as maintenance, replacement of computer cards, etc., while the server is still in operation. In other words, in order for a technician to gain entrance to the server through top panels in the server, the server is slid forward away from the stack of servers in the rack to allow access thereto, while the server is still operational, so that the computer system does not have to go down during service. 
     Known slide assemblies generally include a stationary member having a front bracket and a rear bracket, where the front bracket is rigidly secured to a front column of the rack and the rear bracket is rigidly secured to a corresponding rear column of the rack. One or more slidable members are slidably secured to the stationary member on ball bearings. The inner most slidable member is secured to a side wall of the server. When the technician grasps the server and pulls it away from the rack, the slidable members slide relative to the stationary member allowing the server to be extended out of the rack. 
     The support columns include holes and the front and rear brackets include associated pins. The pins are inserted into the desired holes in the columns to align and hold the slide assembly. Various devices and techniques are known in the art to secure the slide assembly to the columns so that they are securely affixed thereto. These known techniques are sometimes complicated, requiring installation tools and the like to perform the mounting procedure. Also, certain techniques use loose hardware, such as screws and bolts, that may be lost and are inconvenient to keep track of. Further, the configuration of the various rack columns known in the art sometimes prevent the slide assembly to be mounted thereto for a particular column design that the slide assembly was not specifically designed for. 
     SUMMARY OF THE INVENTION 
     In accordance with the teachings of the present invention, a slide assembly for slidably mounting a computer server unit to a rack is disclosed. The slide assembly includes a stationary member and at least one slidable member slidably mounted thereto. A front bracket is mounted to a front end of the stationary member and a rear bracket is mounted to a rear end of the stationary member. The front bracket is secured to a front column of the rack and the rear bracket is secured to the corresponding rear column of the rack to secure the slide assembly thereto. 
     Both the front and rear brackets include a mounting plate having a plurality of pins extending therefrom. The pins are positioned within holes in the rack columns so that the slide assembly can be supported thereto in a certain position. The front bracket and the rear bracket each include a spring element, such as a flat, elongated metal strip. When the pins are inserted into the holes in the rack column, the spring element is moved against its bias force during the installation procedure so that when the pins are fully inserted into the holes in the rack columns, the spring element locks behind the rack column, holding the slide assembly in place. 
    
    
     Additional objects, advantages and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a rear perspective view of a computer server unit slidably mounted to a computer rack on opposing slide assemblies, according to an embodiment of the present invention; 
     FIG. 2 is a perspective view of one of the slide assemblies shown in FIG. 1 removed from the rack and in a fully retracted position, according to an embodiment of the present invention; 
     FIG. 3 is a broken-away, perspective view of one side of a rear mounting bracket of the slide assembly showing mounting spring elements, according to an embodiment of the present invention; 
     FIG. 4 is a broken-away, perspective view of the other side of the rear mounting bracket; 
     FIG. 5 is a front view of a clip device for securing the rear mounting bracket to the slide assembly, according to the invention; 
     FIG. 6 is a broken-away, perspective view of one side of a front mounting bracket of the slide assembly showing mounting spring elements, according to an embodiment of the present invention; 
     FIG. 7 is a broken-away, perspective view of the other side of the front mounting bracket; 
     FIG. 8 is a side view of one of the mounting pins used to secure the slide assembly to the rack, according to the invention; 
     FIG. 9 is a broken-away, perspective view of the front bracket of the slide assembly mounted to a rack column having round mounting holes, according to the invention; 
     FIG. 10 is a broken-away, perspective view of the rear bracket of the slide assembly mounted to a rack column having round mounting holes, according to the invention; 
     FIG. 11 is a broken-away, perspective view of the front bracket of the slide assembly mounted to a rack column having square holes, according to the invention; and 
     FIG. 12 is a broken-away, perspective view of the rear bracket of the slide assembly mounted to a rack column having square holes, according to the invention. 
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The following discussion of the embodiments of the invention directed to a slide assembly for slidably mounting a computer server unit to a rack is merely exemplary in nature, and is in no way intended to limit the invention or its applications or uses. 
     FIG. 1 is a rear perspective view of a computer server unit  10  mounted to a computer rack  12  by a pair of opposing slide assemblies  14  and  16 . The rack  12  includes front columns  18  and rear columns  20  having a particular column configuration for this purpose, as is well understood in the art. The server unit  10  is shown in a fully extended position, where it has been slid out of a front of the rack  12  on the slide assemblies  14  and  16 . In this orientation, a technician can gain access to the server unit  10  while it is still mounted to the rack, and in operation. The slide assembly  14  will be discussed herein, with the understanding that the slide assembly  16  is identical. 
     The slide assembly  14  includes a stationary member  26 , an intermediate slide member  28  and an inner slide member  30 . The slide members  28  and  30  are mounted on ball bearings (not shown) in a nested manner, as is understood in the art. In other words, the stationary member  26  is the widest of the three members, and includes a ball bearing device on its inside surface to which the intermediate slide member  28  is mounted. Likewise, the intermediate slide member  28  includes a ball bearing device mounted on its inside surface to which the inner slide member  28  includes a ball bearing device mounted on its inside surface to which the inner slide member  30  is mounted. The slide assembly  14  further includes a rear mounting bracket  34  rigidly secured to a rear end of the stationary member  26  and a front mounting bracket  38  rigidly secured to a front end of the stationary member  26 . 
     FIG. 2 is a perspective view of the slide assembly  14  removed from the rack  12 , and in a retracted position. FIG. 3 is a perspective view of one side of the rear mounting bracket  34  and FIG. 4 is a perspective of the other side of the bracket  34 . The bracket  34  includes a side plate  32  having opposing flanges  36  and  24 . The bracket  34  further includes an L-shaped mounting portion  40  including an end plate  42  formed at one end of the side plate  32 . A plurality of mounting pins  44 , here three, extend through openings  46  in the end plate  42  and are rigidly mounted thereto by a nut  48 . The mounting pins  44  are inserted within strategically positioned openings  56  in a flange  58  of the rear column  20 , as will be discussed in more detail below. 
     The stationary member  26  includes a pair of pins  70  and  72  and the bracket  34  includes a plurality of extended slots  76  and  78 . During assembly, the pins  70  and  72  are aligned and pushed through the slots  76  and  78  at the location suitable for proper spacing between the columns  18  and  20 . A clip device  80  is then positioned on the pins  70  and  72  and against the side plate  32  opposite to the stationary member  26 . The clip device  80  is clipped to the pins  70  and  72  so that the bracket  34  is maintained in the proper position. A front view of the clip device  80  is shown in FIG.  5 . The clip device  80  includes a back plate  82  having slots  84  and  86  and a front plate  88  having openings  66  and  68  that receive and lock the pins  70  and  72 . 
     According to the invention, the rear bracket  34  includes a spring assembly  94  mounted to a rear surface  92  of the side plate  32  by a nut and bolt assembly  96 . As will be discussed in more detail below, the spring assembly  94  includes a pair of flat metal spring elements  98  and  100  that are positioned side by side and against each other, as shown. As is apparent, the spring element  100  is slightly longer than the spring element  98 . The spring elements  98  and  100  extend relative to an opening  102  between the side plate  32  and the mounting portion  40 . Thus, the spring elements  98  and  100  can flex in a direction perpendicular to the plane of the side plate  32  relative to the opening  102 . 
     The front mounting bracket  38  is similar in configuration to the rear bracket  34 . FIG. 6 is a perspective view of one side of the bracket  38  and FIG. 7 is a perspective view of the other side of the bracket  38 . The bracket  38  also includes a side plate  110  having opposing flanges  112  and  114 . The front mounting bracket  38  further includes an L-shaped mounting portion  116  including an end plate  118  formed at the end of the side plate  110 . A plurality of mounting pins  120 , here three, extend through openings  122  in the end plate  118  and are rigidly mounted thereto. The mounting pins  120  are inserted within strategically positioned openings  124  in a flange  126  of the front column  18 . The front bracket  38  is rigidly secured to the stationary member  26  by a nut and bolt assembly  128  extending through the side plate  110  and the stationary member  26 . The distance between the brackets  34  and  38  and the end plates  42  and  118  is thus set by the position of the rear bracket  34  relative to the stationary member  26 , as discussed above. Of course, the front bracket  38  can be selectively mounted to the stationary member  26  by the clip device  80 . 
     The front bracket  38  also includes a spring assembly  130  including flat metal spring elements  132  and  134  positioned against each other. As is apparent, the spring element  134  is longer than the spring element  132 . The elements  132  and  134 , are secured to a rear surface  136  of the side plate  110  by a nut and bolt assembly  138 . The spring elements  132  and  134  extend relative to an opening  142  in the bracket  38  between the side plate  110  and the mounting portion  116 . A pair of L-shaped flanges  144  and  146  secured to the side plate  110  are formed around the spring elements  132  and  134 , as shown, to prevent buckling of the elements  132  and  134 . 
     As is known in the art, rack columns come in different designs where the holes have different diameters and may be round or square. The slide assembly  14  of the present invention can be used with many rack designs. According to the invention, the pins  44  and  120  are dual diameter pins to accommodate openings in the columns  18  and  20  of different sizes and shapes. The dual diameter pins  44  and  120  are used in cooperation with the spring elements  98 ,  100 ,  132  and  134  to rigidly mount the slide assembly  14  to the columns  18  and  20  without the need for tools or complicated securing devices. The spring assemblies  94  and  130  also allow the slide assembly  14  to be easily removed from the columns  18  and  20 . 
     FIG. 8 is a side view of one of the pins  44  showing the dual diameter configuration. The pins  120  would look the same. The pin  44  includes a base portion  140  of one diameter and a tip portion  142  of a narrower diameter defining a shoulder  144  therebetween. A threaded post  146  extends from the base portion  140  opposite to the tip portion  142 . The threaded post  146  extends through an opening in the end plate  42  and is secured thereto by the nut  48 . 
     FIG. 9 is a broken-away, perspective view of the front bracket  38  mounted to the front column  18 . In this embodiment, the front column  18  includes the round holes  124  of a known diameter. Because the holes  124  are round and of a limited diameter, the pins  120  only extend through the holes  124  far enough to contact the shoulder  144  between the base portion  140  and the tip portion  142 . In other words, the diameter of the base portion  140  and the diameter of the tip portion  142  are selected so that the tip portion  142  fits through the holes  124 , but the base portion  140  does not. Thus, a gap between the flange  126  and the end plate  118  that is about the width of the base portion  140  is provided. The bracket  38  is locked to the column  18  by the shorter spring element  132  that snaps behind the flange  126  opposite to the end plate  118  to hold the bracket  38  thereto. The other spring element  134  rests against an outside edge of the flange  126 , and is not operable to hold the bracket  38  in place in this embodiment. 
     FIG. 10 is a broken-away, perspective view of the rear bracket  34  secured to the rear column  20 , where the holes  56  are round. As above, only the tip portion  142  extends through the holes  56  where the shoulder  144  of the pin  44  abuts against the flange  58  providing a space between the end plate  42  and the flange  58 . In this configuration, the shorter spring element  98  snaps behind the flange  58  opposite to the end plate  42 , and secures the bracket  32  thereto. The spring element  100  is too long to fit behind the flange  58  in this configuration, and thus rests against an edge of the flange  58 . Thus, it is the spring element  98  that holds the bracket  34  to the column  20 . As will be appreciated by the those skilled in the art, if the size and shape of the various and known holes in the columns  18  and  20  were fixed, then only one spring element would be required. 
     According to one embodiment of the invention, the pins  44  are shaped to allow the slide assembly  14  to be secured to the columns of a rack that may have square holes, or round holes larger than the round holes  56 . FIG. 11 is a broken-away perspective view of the front bracket  38  secured to a column  170  including a flange  174  having square holes  172 . The square holes  172  have a larger diameter than the round holes  124  so that the base portion  140  of the pin extends through the hole  172  until the end plate  118  is positioned flush against the flange  174  of the column  170 . In this configuration, the spring element  132  is too short to hold the bracket  38  rigidly in place, and thus the longer spring element  134  is used for this purpose. As shown, the spring element  134  snaps behind the flange  174  to hold the bracket  38  in place. 
     In FIG. 12, the rear bracket  34  is secured to a column  180  having a flange  182  and square holes  184  extending therethrough. As above, the pin  44  extends through the hole  184  until the end plate  42  abuts against the flange  182 . In this configuration, the spring element  98  is too short to hold the rear bracket  34  securely in place, but the spring element  100  has the right length to snap behind the flange  182  opposite to the end plate  42  and hold the bracket  34  in place. In this configuration, the shorter spring element  98  does not act to hold the bracket  34  in place. 
     When the slide assembly  14  is to be removed from the rack  12 , the appropriate spring element is flexed into the opening so that the bracket is not secured to the column, and can be removed in that manner. 
     The foregoing discussion discloses and describes merely exemplary embodiments of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims, that various changes, modifications or variations can be made therein without departing from the spirit and scope of the invention as defined in the following claims.