Abstract:
A screw-less fixing structure is provided for users to mount the add-on card onto a PC. The screw-less fixing structure comprises a support plate, a rotational pressing plate, a positioning device, and a spring wire. When a user attempts to replace an old add-on card with a new one, he needs only to release the screw-less fixing structure by grasping and pulling the handling portion of the spring wire, replace the old add in card with the new one, and finally tighten the screw-less fixing structure by grasping and pushing the spring wire to reach the tightening state. In the above procedures for replacing the add-on card, the user does not need any additional tool nor screw so that the present invention has the advantages of safe, fast, easy and convenient to use.

Description:
REFERENCE TO RELATED APPLICATION 
     The present application claims priority to Taiwan application no. 090116413, entitled “Screw-less Fixing Structure,” filed on Jul. 4, 2001. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a screw-less fixing structure, and more particularly, to a screw-less fixing structure for mounting the add-on card onto a Personal Computer without using screw and screwdriver. 
     2. Description of the Prior Art 
     Personal computer has become more and more popular, and is no longer an advanced technical tool for the professional persons to rely on for solving highly sophisticated problems. Also, when the user learn more about using the PC, he will learn more about the hardware of the PC as well. Therefore, the user&#39;s behavior has been changed from the conventional type of simply buying and using a PC to the modern type of buying the hardware parts and assembling a PC of his own. In addition, in the fast growing computer industry, new hardware is developed and marketed at a rapid speed, and it is often necessary to upgrade the “old” PC to a more advanced level. Such being the circumstances, it may be preferable for a user to upgrade his PC by himself since this is cheaper and easier than buying a new PC. 
     Accordingly, a PC is required to be easily assembled/disassembled so as to facilitate a user to upgrade his PC by himself. Among all of the hardware of a PC, add-on cards, such as the display card, the video card and the network card, are the most common ones to be upgraded. According to the prior art, a method of upgrading the add-on card is described as follows. 
     Please refer to FIG. 1, which is a perspective view showing a conventional arrangement of an add-on card in a PC. Typically, a PC has a slot fixing module  101  disposed on the inner side of a back plate of the PC. The slot fixing module  101  has a plurality of fixing slots  102  (usually seven slots) for fixing the add-on card  110 . It can be seen that there is a bracket  111  disposed on one end of the add-on card  110 , and a fixing sheet  112  is bent outward to form at one end of the bracket  111  for attaching to the fixing plane  104  of the slot fixing module  101 . For assembling the add-on card  110  onto the PC, users have to insert the add-on card  110  into the slot (not shown) on the motherboard. At the same time, the bracket  111  covers the fixing slot  102 , and the connect portion (not shown) of the add-on card  110  can be exposed to connect with the peripherals such as a display unit, a speaker, or the like. There is a screw hole  103  formed on the fixing plane  104 , and correspondingly there is a U-shape portion formed in the fixing sheet  112  so that the screw hole  103  can mate with the U-shape portion when the fixing sheet  112  attaches to the fixing plane  104 . Accordingly, the users can apply a screwdriver and use a screw to fasten the add-on card  110  to the slot fixing module  101 . 
     According to the above description, an add-on card can be successfully mounted to the slot fixing module; however, a screwdriver and a screw are required for the assembly and disassembly of an add-on card. It is also very inconvenient to mount the add-on card in such a manner, particularly the screw is so tiny and may be easily lost, and the user&#39;s hand may be slashed if he is not a skilled person. All of these disadvantages show that the prior art is not user-friendly and cause difficulties when upgrading the add-on card. 
     SUMMARY OF THE INVENTION 
     It is therefore a primary object of the present invention to provide a screw-less fixing structure for fixing the add-on card onto a PC that is more convenient and user-friendly. 
     A PC includes a back plate and a slot fixing module. The slot fixing module (it is a standard specification specified by INTEL), which is installed inside the PC, has a fixing plane and a plurality of slots for fixing the add-on card. The add-on card includes a bracket, and one end of the bracket is bent to form a fixing sheet. For fixing the add-on card, the fixing sheet is attached to the fixing plane, and the bracket is covered on the slot. 
     The screw-less fixing structure comprises a support plate, a rotational pressing plate, a positioning device, and a spring wire. The support plate is fixed on the back plate and has two pivot seats at two opposed edges The rotational pressing plate is pressed on the fixing plane against the add-on card. The rotational pressing plate has two protrusion pivots and the arched bearing. The two protrusion pivots of the rotational pressing plate are pivotally coupled to the two pivot seats of the support plate, so that the rotational pressing plate can pivot relative to the support plate for switching between the releasing state and the tightening state. The spring wire has a first hook pivot formed at one end and a second hook pivot formed at the other end. The two hook pivots of the spring wire pivotally couples to the arched bearing of the rotational pressing plate such that the spring wire can pivot relative to the rotational pressing plate and can be coupled to the positioning device for fastening the rotational pressing plate in the tightening state. 
     When a user attempts to replace an old add-on card with a new one, he needs only to release the screw-less fixing structure by grasping and pulling the handling portion of the spring wire, replace the old add-on card with the new one, and finally tighten the screw-less fixing structure by grasping and pushing the spring wire to reach the tightening state. In the above procedures for replacing the add-on card, the user does not need any additional tool nor screw so that the present invention has the advantages of safe, fast, easy and convenient to use. 
     These and other attributes of the present invention will become more clear upon a thorough study of the following description of the preferred embodiments for carrying out the invention, particularly when reviewed in conjunction with the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view showing the conventional arrangement of the add-on card in a PC; 
     FIG. 2 is a preferred embodiment showing the arrangement of the screw-less fixing structure in a PC according to the present invention; 
     FIG. 3A is a perspective view showing the assembly of support plate, the rotational pressing plate, and the spring wire as shown in FIG. 2; 
     FIG. 3B is a partial exploded view of the assembly shown in FIG. 3A; 
     FIG. 4 is a schematic view showing the arrangement of the back plate shown in FIG. 2; 
     FIG. 5A is a side view showing that the screw-less fixing structure attaches to the slot fixing module in a tightening state according to the present invention; 
     FIG. 5B is a side view showing that the screw-less fixing structure separates from the slot fixing module in a releasing state according to the present invention; 
     FIG. 6A is a schematic view showing one design of the positioning device of the preferred embodiment according to the present invention; and 
     FIG. 6B is a schematic view showing another design of the positioning device of the preferred embodiment according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Please refer to FIG.  2 . FIG. 2 is a preferred embodiment showing the arrangement of the screw-less fixing structure in a PC according to the present invention. The screw-less fixing structure comprises a support plate  210 , a rotational pressing plate  220 , a spring wire  230 , and two sets of positioning device  240 . The support plate  210  is fixed on the inner side of a back plate  200  and couples with the rotational pressing plate  220  such that the rotational pressing plate  220  can pivot with respect to the support plate  210 . For fixing the add-on card in a tightening state, the rotational pressing plate  220  is rotated to a position as shown in the drawing, attached to the fixing plane  104 , and pressed against the fixing sheet  112  for fastening the add-on card  110 . In such a tightening state, the fixing sheet  112  is sandwiched between the rotational pressing plate  220  and the fixing plane  104 ; therefore, the fixing sheet  112  is not shown in the drawing. On the other hand, the spring wire  230 , which is pivotally installed on the rotational pressing plate  220 , can pivot with respect to the rotational pressing plate  220 . After the rotational pressing plate  220  has been pressed against the fixing sheet  112 , the users need only to rotate the spring wire  230  to a proper position and couple it to the positioning device  240 ; consequently, the rotational pressing plate  220  stably presses against the fixing sheet  112  and the fixing plane  104  to fasten the add-on card  110 . According to the foregoing description, the users no more need a screwdriver or screw for fixing the add-on card  110  onto the PC, and all they have to do is to rotate the spring wire  230  and then couple it to the positioning device  240 . 
     Please refer to FIG.  3 A. FIG. 3A is a perspective view showing the assembly of the support plate  210 , the rotational pressing plate  220 , and the spring wire  230  as shown in the FIG.  2 . As shown in the drawing, after the support plate  210  has been coupled with the rotational pressing plate  220 , the rotational pressing plate  220  can pivot about an axial line  301  relative to the support plate  210 . Similarly, after rotational pressing plate  220  has been coupled with the spring wire  230 , the spring wire  230  can pivot about an axial line  302  relative to the rotational pressing plate  220 . The axial lines  301  and  302  are straight lines and parallel to each other, while the axial line  301  is fixed as shown in the drawing, and the axial line  302  is traveled to follow the movement of the rotational pressing plate  220 . In order to illustrate the constitution and the operation of the screw-less fixing structure, the components of the screw-less fixing structure are described in a more detailed manner as follows. 
     Please refer to FIG.  3 B. FIG. 3B is a partial exploded view of the assembly of the support plate  210 , the rotational pressing plate  220 , and the spring wire  230  as shown in FIG.  3 A. Two inserting extrusions  312  and  314  are provided on one edge of the support plate  210 , and a screw hole  313  is located at the middle of the support plate  210 . By means of the inserting extrusions  312 , 314  and the screw hole  313 , the support plate  210  is fixed on the back plate  200 . The support plate  210  further comprises two pivot seats  311  and  315  formed separately on two opposed edges. The rotational pressing plate  220  has two protrusion pivots  321 ,  325  which protruded separately from two opposed edges thereof so as to be respectively received in the two pivot seats  311 ,  315 . By inserting respectively the two protrusion pivots  321 ,  325  through the two corresponding pivot seats  311 ,  315 , the rotational pressing plate  220  is coupled to, and pivots relative to, the support plate  210 . Furthermore, the rotational pressing plate  220  has a plurality of grasping portion  326 , for example, eight portions as shown in the drawings. After the rotational pressing plate  220  has joined to the slot fixing module  101 , each of the grasping portion  326  presses against the slot fixing module  101 . The grasping portions  326  may be alternatively formed as a strip without departing, from the spirit of the present invention. In addition, the rotational pressing plate  220  comprises the arched bearing  323  which includes two arched sheets  322 , 324  so as to respectively receive the hook pivots  332 , 334  of the spring wire  230 . The spring wire  230  is an elastic steel wire and formed as shown in the drawing. The spring wire  230  has a hook pivot  332  bent to form at one end and a hook pivot  334  bent to form at the other end. The hook pivots  332 ,  334  are received in the arched sheets  322 ,  324 , respectively, such that the spring wire  230  can pivot with respect to the rotational pressing plate  220  and couple to the positioning device  240  in a tightening state. The spring wire  230  comprises a handling portion  331  formed as a bow at the middle portion, and two positioning portions  333 ,  335  beside the handling portion  331  for coupling to the positioning device  240 . 
     Please refer to FIG.  4 . FIG. 4 is a schematic view showing the arrangement of the backs plate  200  shown in FIG.  2 . The back plate  200  comprises a screw hole  403  and two through holes  402 ,  404 , and the positioning device  240  on the inner side. The positioning device  240  comprise a first pair of projecting studs  411  and a second pair of projecting studs  412  for coupling to the spring wire  230 . The screw hole  403  corresponds to the screw hole  313  of the support plate  210 , the through hole  402  corresponds to the inserting extrusion  312 , and the through hole  404  corresponds to the inserting extrusion  314 . In order to fix the support plate  210  onto the back plate  200 , the inserting extrusion  312  is coupled to the through hole  402 , the inserting extrusion  314  is coupled to the through hole  404 , and the screw hole  403  and the screw hole  313  are screwed together by a screw such that the support plate  210  can be fixed on the back plate  200 . 
     Please refer to FIG.  5 A. FIG. 5A is a side view showing that the screw-less fixing structure attaches to the slot fixing module  101  in a tightening state according to the present invention. When the screw-less fixing structure  101  is in the tightening state  500 , the rotational pressing plate  220  attaches to the fixing plane  104  so as to fasten the add-on card  110 . At the same time, the spring wire  230  is rotated to a proper position such that the positioning portion  333 , 335  couple to the second pair of projecting studs  412 . For disassembling the add-on card  110 , the user can grasp the handling portion  331  and pull the spring wire  230  for releasing and rotating the rotational pressing plate  220  so that the rotational pressing plate  220  comes to the releasing state  501 . Please refer to the FIG.  5 B. FIG. 5B a side view showing that the screw-less fixing structure separates from the slot fixing module  101  in a releasing state  501  according to the present invention. A when the screw-less fixing structure Is in the releasing state  501 , the rotational pressing plate  220  is rotated to a position as shown in the drawing. At the same time, the spring wire  230  is rotated to another proper position such that the positioning portions  333 , 335  couple to the first pair of projecting studs  411 . After the old add-on card is replaced by a new one, the user then grasps the handling portion  331  and pushes the spring wire  230  for rotating the rotational pressing plate  220  to the proper position so that the rotational pressing plate  220  comes to the tightening state  500 . 
     In order to facilitate the coupling of the positioning device  240  and the positioning portions  333 , 335 , the positioning device  240  is designed into a special form. Please refer to FIG.  6 A. FIG. 6A is a schematic view showing one design of the positioning device of the preferred embodiment according to the present invention. The positioning device  240  comprises a first pair of projecting studs  411  and a second pair of projecting studs  412 , both projects from the inner surface of the back plate  200 . More particularly, the studs  411 , 412  are provided with protruding portions so that the positioning portion  333 , 335  of the spring wire  230  can be easily coupled thereto. Alternatively, the positioning device  240  can also be designed as a strip stopper  640  as shown in the FIG.  6 B. FIG. 6B is a schematic view showing another design of the positioning device of the preferred embodiment according to the present invention. The strip stopper  640  has a releasing end  611  and a tightening end  612 . the releasing end  611  and the tightening end  612  are also provided with protruding portions so that the positioning portion  333 , 335  of the spring wire  230  can be easily coupled thereto. 
     According to the above detailed description of the present invention, when a user attempts to assemble/disassemble an add-on card, he does not need to use screw nor screwdriver. Therefore, the present invention provides a simple structure and prevents the user from preparing any tool or screw which may be easily lost. 
     In contrast to the prior art, the present invention possesses the following advantages: 
     (a). Without using any tool, the assembly/disassembly of an add-on card can be performed easily. 
     (b). For assembling/disassembling an add-on card, the users no more need the screw, which is tiny and may be easily lost. 
     (c). The screw-less fixing structure is simple in its structure and is easy to be used; users can assemble it by themselves without changing the original structure of the PC. Moreover, the screw-less fixing structure can be sold as an optional device and is easy to be promoted. 
     While the present invention has been shown and described with reference to a preferred embodiment thereof, and in terms of the illustrative drawings, it should not be considered as limited thereby. Various possible modifications, omissions, and alternations could be conceived of by one skilled in the art to the form and the content of any particular embodiment, without departing from the scope of the present invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.