Abstract:
A releasable latching apparatus and method of operation for securing a component of a computer system to a computer housing. The latching apparatus includes a casing and a shaft integrated with the casing such that the shaft is operable to move relative to the casing. Incorporated into the latching apparatus is a collet that extends along the shaft. The collet includes a locking portion, which can releasably secure a computer component to a housing by extending away from the shaft and capturing an element of the computer housing.

Description:
TECHNICAL FIELD OF THE INVENTION 
     This invention relates in general to the field of electronic equipment enclosures and, more particularly, to a method and apparatus for releasably securing a computer system component within a housing. 
     BACKGROUND OF THE INVENTION 
     Computer systems are becoming increasingly complex. It is not unusual for a single computer system to include a combination of several computer components. Though the components may include diverse types of equipment (e.g., telephonic equipment or computing equipment), system users usually prefer that the system be housed in a common enclosure. This preference influenced the development of rack storage devices (Racks). Racks are standard in the computer industry and allow components to be placed within them in a modular fashion such that various combinations of components can be integrated into a single system. 
     A number of vendors sell standard EIA (Electronics Industries Association) racks, which comply with EIA specifications including size limitations. Many of these racks employ a fairly simple slide device for securing the system components within the rack. The slide device extends from the rack cabinet to facilitate the accessing of the component and retracts into the cabinet to allow for the in-place securing of the component. The slide device is not, however, essential. 
     Whether a rack employs the slide device or some other component mounting device, the component, itself, must be connected to the rack in a secure manner. Conventionally, this secure connection is provided with a series of male and female threaded devices. In these conventional systems, the threaded devices connect the component, or some part of it, to the housing. Additional threaded devices may also be used to mount pull handles onto the component. These pull handles allow the component to be pulled from the rack once the component is no longer secured in place. 
     There are several disadvantages associated with the conventional approach&#39;s reliance on threaded devices. For example, the conventional system requires the use of a significant number of parts at each secure connection point (e.g., a bolt, a washer and a nut). This in turn creates at least two complications. First, the conventional system creates alignment issues (i.e., the nut, which is secured to the rack cabinet and is intended to receive the bolt, must be correctly located relative to the bolt). And second, the combination of numerous parts and manufacturing challenges (e.g., alignment problems), necessarily increases manufacturing costs. 
     An additional problem arises when a user seeks to un-secure and/or re-secure a component within the rack. The un-secure/re-secure procedure is unduly time consuming and complicated as a result of the many threaded parts. Frequently, a component will be secured in place at four or more connection points. As a result, the user must unthread at least four bolts from their associated receiving nuts and keep track of these four bolts while the component is in an unsecured state. 
     SUMMARY OF THE INVENTION 
     In accordance with teachings of the present invention, a method and apparatus for releasably securing a computer system component within a housing are disclosed that provide significant advantages over prior technologies. 
     According to one aspect of the present invention a releasable latching apparatus for securing a component of a computer system to a computer housing is disclosed. One embodiment of the apparatus includes a casing and a shaft integrated with the casing such that the shaft is operable to move relative to the casing. This movement could be rotational. It could also be, among other alternatives, linear along the shaft. Coupled to the shaft is an actuator, which could include a handle. It could also include a keyed mechanism for key actuation. Incorporated into the latching apparatus is a collet that extends along the shaft. The collet includes a locking portion, which can releasably secure a computer component to a housing by extending away from the shaft and capturing an element of the computer housing. In one embodiment, the collet includes a projecting finger, and the captured element of the computer housing includes a hole that extends through an EIA rail, which is secured to the rack housing. In another embodiment, the collet includes a spring finger that is operable to flex and extend away from the shaft. A variety of mechanisms can be used to cause the collet to extend away from the shaft. For example, the shaft could include a tapered end with a varying cross sectional area. As the shaft is moved and a portion of the shaft having a larger cross sectional area is brought into contact with an inner surface of the collet, the collet will extend outward and capture an element of the computer housing. In another embodiment, the shaft could include a cam having at least one lobe. As the shaft is rotated, the cam lobe is brought into contact with the inner surface of the collet and forces the collet to extend outward and capture an element of the computer housing. 
     A technical advantage of the present invention is a reduction in the number of total parts and, resultantly, a reduction in manufacturing time and cost. The above described apparatus could be a single part that directly couples to a component face plate. This coupling could be accomplished in a number of ways (e.g., a locking clip attached to the apparatus on the back side of the face plate). Moreover, the apparatus could include a handle coupled to the actuator. Because the apparatus is securely attached to the component, this coupled handle eliminates the need for additional pull handles, which are necessary in conventional systems. 
     Another technical advantage of the present invention is ease of alignment. For example, one embodiment of the apparatus is operable to engage and capture a hole in an EIA rail, which is fixed to the housing. A typical EIA rail has holes displaced incrementally along its length. As such, there is no requirement for the accurate placing of a specific receiving device. 
     Additionally, the latching apparatus of the present invention could be manufactured to have quarter turn actuation. A latching apparatus that is securely attached, for example, to the face plate of a component and operates with quarter turn actuation would greatly reduce the effort required to un-secure and/or re-secure a component within the rack. 
     Other technical advantages should be apparent to one of skill in the art from the following description, drawings and claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete understanding of the present invention and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, in which like reference numbers indicate like features, and wherein: 
     FIG. 1 depicts a rack cabinet frame with an attached EIA rail with which an apparatus incorporating teachings of the present invention could engage; 
     FIG. 2 depicts a computer component having a face plate, which can provide an attachment point for an apparatus incorporating teachings of the present invention; 
     FIGS. 3A and 3B depict one embodiment of an apparatus incorporating teachings of the present invention in an actuated and unactuated state, the depicted embodiment includes a spring collet and a cam lobe for causing a portion of the spring collet to extend away from the shaft; 
     FIG. 4 depicts one embodiment of an apparatus incorporating teachings of the present invention including a projecting finger and a cam lobe for causing a portion of the projecting finger to extend away from the shaft; and 
     FIG. 5 depicts one embodiment of an apparatus incorporating teachings of the present invention including a projecting finger and a tapered shaft for causing a portion of the projecting finger to extend away from the shaft. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Preferred embodiments of the present invention and its advantages are best understood by reference to FIGS. 1 through 5, wherein like numbers are used to indicate like and corresponding parts. 
     FIG. 1 depicts a rack cabinet frame, identified generally at  10 , with an attached EIA rail  12  with which an apparatus incorporating teachings of the present invention could engage. EIA rail  12  runs the vertical length of rack cabinet frame  10 . A number of holes, depicted at  16 , extend through EIA rail  12 . Rack cabinet frame  10  also includes a slide mechanism  14 . Slide mechanism  14  is operable to support various computer components. Rack cabinet frame  10  as well as EIA rail  12  are designed and dimensioned in accordance with EIA standard EIA-310-D, the Electronic Industries Association&#39;s standard for Cabinets, Racks, Panels, and Associated Equipment. 
     FIG. 2 depicts an embodiment of the present invention, representatively depicted at  26  and a computer component, indicated generally at  20 , having a face plate  22 . Face plate  22  has an associated flange  28 , which extends beyond the side wall  30  of component  20  and provides a location for an attachment point  24 . Attachment point  24  represents a point at which embodiment  26  could be securely attached to associated flange  28 . In another embodiment, attachment point  24  could be located on a face plate (e.g., a face plate that extended beyond side wall  30  without the addition of a flange). Though represented as a round hole, attachment point  24  could have other shapes (e.g., a slotted hole). One method of securing embodiment  26  at attachment point  24  could employ a locking clip  32 . 
     Once embodiment  26  is securely attached to associated flange  28 , component  20  can be placed at a selected location within computer housing  34 . After its placement, component  20  may be secured in place by engaging with embodiment  26  a hole, similar to those indicated at  16 , associated with EIA rail  12 . As depicted in FIG. 2, EIA rail  12  may be secured within computer housing  34 . 
     FIGS. 3A and 3B depict one embodiment  40  of an apparatus incorporating teachings of the present invention in an actuated and unactuated position. FIG. 3A depicts embodiment  40  in an unactuated position. Embodiment  40  includes a spring collet  42 , which stretches between embodiment  40 &#39;s casing  54  and collet housing  58 . Collet housing  58  may also operate as an allignment guide. Embodiment  40  also includes a cam lobe  44  for causing a portion of spring collet  42  to extend away from a shaft  46 . The portion of spring collet  42  that extends away includes a medial head  48  with a locking notch  50 . Locking notch  50  includes a shoulder  52 , which may operate to capture an element of a computer housing. In FIG. 3A, the engaged element includes hole  16  that extends through EIA rail  12 . 
     Embodiment  40  also includes a casing  54  and a handle actuator  56 . Casing  54  and handle actuator  56  at least partially compose the head end  58  of embodiment  40 . Embodiment  40 &#39;s tail end  60  is dimensioned such that it will fit through a face plate hole  62 . Face plate hole  62  extends through an extended face plate  63  and provides an attachment point for embodiment  40 . A portion of casing  54  is dimensioned such that it will not fit through face plate hole  62  and, as a result, creates an attachment shoulder  64 . Attachment shoulder  64 , in conjunction with locking clip  32 , may operate to secure embodiment  40  to extended face plate  63 . 
     FIG. 3B depicts embodiment  40  actuated and releasably secured to EIA rail  12 . In the actuated position depicted in FIG. 3B, medial head  48  is extended away from shaft  46  by cam lobe  44 . In this extended position, shoulder  52  captures EIA rail  12  and secures embodiment  40  in position. 
     FIG. 4 depicts an embodiment  68  of an apparatus incorporating teachings of the present invention wherein the invention includes a projecting finger  72  having a shaft side surface  74 . In FIG. 4, a mechanical device including a shaft  46  and a cam  76  having at least one cam lobe  44  can operate to cause a portion of projecting finger  72  to extend away from shaft  46 . Embodiment  68  also includes a casing  54  and a hand operated actuator  78 , which may be coupled to shaft  46 . Hand operated actuator  78  may include or potentially be replaced with a key actuator, an actuator that requires a key for actuation. In embodiment  68 , shaft  46  may rotate relative to casing  54 . When actuator  78  and, resultantly, shaft  46  are rotated, cam lobe  44  may be brought into contact with shaft side surface  74 . Said contact causes projecting finger  72  to extend away from shaft  46 . 
     In FIG. 5, embodiment  70  incorporates teachings of the present invention and includes a mechanical device including a shaft  80  having a tapered end  82 , which can operate to cause a portion of projecting finger  72  to extend away from shaft  80 . Tapered end  82  includes sections with different cross sectional areas. For example, section  84  has a larger cross sectional area than section  86 . Embodiment  70  also includes a casing  54  and a hand operated actuator  78 , which is coupled to shaft  80 . In embodiment  70 , shaft  80  can move linearly relative to casing  54  in the axial direction defined by shaft  80 . When moved in an actuating direction, a portion of shaft  80  with a large cross sectional area, for example portion  84 , may be brought into contact with shaft side surface  74 . Said contact causes projecting finger  72  to extend away from shaft  80 . 
     Although the present invention has been described in detail, it should be understood that various changes, substitutions and alterations can be made thereto without departing from the sphere and scope of the invention as defined by the appended claims.