Abstract:
A power plug is proposed, including a terminal base having at least one conductive terminal and a ground terminal; an electric wire having core wires connected to the conductive terminal and ground terminal, respectively; a cover integrally connected to the terminal base; and a ground mechanism for grounding isolated metal parts (such as screws). The ground mechanism can prevent quality of power provided through the power plug from being deteriorated by electromagnetic effect of the metal parts.

Description:
FIELD OF THE INVENTION 
     The present invention relates to power plugs, and more particularly, to a power plug for preventing quality deterioration of power supplied through the power plug. 
     BACKGROUND OF THE INVENTION 
     Recently, in the realm of audio equipment, much attention and concern are directed toward influence of power supply on audio quality, or timbre deterioration caused by instability of current passing through the audio equipment. 
     In response to the above problems, a power plug having stronger mechanical strength and stability is applied to the audio equipment, wherein joints or terminals of the power plug are preferably made for reducing electrical resistance of current flow; this desirably improves timbre, resolution and other critical properties of the audio equipment. 
     However, in order to enhance mechanical strength and stability, the foregoing power plug is internally provided with a plurality of metallic screws. When current from a power supply flows inside the power plug, a magnetic field produced by the current flow induces variation in internal electron energy levels of metal atoms of the metallic screws that are located nearby the current flow, whereby part of electrons in the metal atoms are ionized, and generates an electron flow inside the metallic screws. This electron flow accordingly produces a magnetic field, which interferes with stability of the current flow from the power supply, thereby leading to timbre deterioration of the audio equipment in operation of the power plug, so that satisfactory audio quality still cannot be achieved. 
     SUMMARY OF THE INVENTION 
     A primary objective of the present invention is to provide a power plug, in which a ground mechanism can prevent the occurrence of electron ionization in the power plug, allowing stability of current flowing through the power plug to be effectively assured. 
     In accordance with the foregoing and other objectives, the present invention proposes a power plug, comprising: a terminal base having at least one conductive terminal and a ground terminal; an electric wire having core wires connected to the conductive terminal and the ground terminal, respectively; a cover integrally connected to the terminal base by a plurality of first screws; and a ground mechanism having a conductive member for connecting the first screws to the ground terminal, allowing the first screws to be grounded. The conductive member of the ground mechanism is a copper plate, wherein a central portion of the copper plate is connected to the ground terminal, and two ends thereof can respectively extend to come into contact with the first screws. 
     Further, the conductive terminal and ground terminal of the terminal base can be in the form of a male or female power plug. 
     In another embodiment, the power plug of the invention further comprises a wire fixing mechanism installed in the cover, which wire fixing mechanism includes a press board positioned at where the electric wire passes thereby, and a clamping member underneath the press board; and two second screws respectively penetrating through the cover and screwed at two ends of the press board. The ground mechanism includes a first conductive member for connecting the first screws to the ground terminal, allowing the first screws to be grounded; a second conductive member for interconnecting the two second screws; and a third conductive member for connecting the first screws to the second conductive member, so as to ground the second screws via the second conductive member and the first screws. A central portion of the first conductive member is connected to the ground terminal, and two ends thereof can respectively extend to come into contact with the first screws. The second conductive member is a copper plate, and capable of extending to come into contact with the second screws, respectively. And, the second conductive member has a central portion thereof being exposed to one screw hole for allowing one of the first screws to be screwed therein; the third conductive member is a metallic spring installed in this screw hole, and is pressed when the first screw is screwed into the screw hole, in a manner that one end of the metallic spring abuts against the first screw, and the other end of the metallic spring adjoins the central portion of the second conductive member. 
     In a further embodiment, the power plug of the invention comprises: a terminal base having at least one conductive terminal and a ground terminal; an electric wire having core wires connected to the conductive terminal and the ground terminal, respectively; two covers integrally connected to the terminal base by a plurality of screws, and capable of being coupled to each other for enclosing the conductive terminal and the ground terminal therein; and a ground mechanism having a conductive member for connecting the screws to the ground terminal, allowing the screws to be grounded. The conductive member of the ground mechanism is a copper plate provided on an inner wall of one of the covers, wherein one end of the copper plate extends toward the ground terminal, and can be pressed to abut against the ground terminal when the two covers are coupled to each other, whereas the other end of the copper plate extends to screw holes, allowing the screws to be respectively screwed into the screw holes and come into contact with the copper plate. 
     In a further embodiment, the power plug of the invention comprises: a terminal base having at least one conductive terminal; an electric wire having core wires connected to the conductive terminal and a ground terminal, respectively; a cover integrally connected to the terminal base by a plurality of screws; a ground wire having one end thereof being connected to the ground terminal, and the other end thereof extending to outside of the power plug and connected to an external ground device; and a ground mechanism for connecting the screws to the ground terminal of the ground wire, allowing the screws to be grounded. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention can be readily understood by the following detailed description of the preferred embodiment, with reference made to the accompanying drawings, wherein: 
     FIG. 1 is a perspective schematic diagram of a power plug of a first preferred embodiment of the invention; 
     FIG. 2 is a perspective dissection diagram showing a terminal base with a ground mechanism in a power plug of a first preferred embodiment of the invention; 
     FIG. 3 is a cross-sectional view of a terminal base with a ground mechanism in a power plug of a first preferred embodiment of the invention; 
     FIG. 4 is a cross-sectional view of an upper part of a cover in a power plug of a first preferred embodiment of the invention; 
     FIG. 5 is a perspective dissection diagram showing another example of a terminal base with a ground mechanism in a power plug of a first preferred embodiment of the invention; 
     FIG. 6 is a top view of a power plug of a second preferred embodiment of the invention; 
     FIG. 7 is a side view of a power plug of a second preferred embodiment of the invention; 
     FIG. 8 is a front view of a power plug of a second preferred embodiment of the invention; 
     FIG. 9 is a back view of a power plug of a second preferred embodiment of the invention; 
     FIG. 10 is a perspective structural diagram showing an unassembled power plug of a second preferred embodiment of the invention; 
     FIG. 11 is a top view of a power plug of a third preferred embodiment of the invention; and 
     FIG. 12 is a cross-sectional view of a power plug of a third preferred embodiment of the invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     First Preferred Embodiment 
     Illustrated in FIG. 1 is a perspective schematic diagram of a power plug of a first embodiment of the present invention. As shown in the drawing, the power plug  1  comprises a terminal base  10  having two conductive terminals  100  and a ground terminal  101 ; an electric wire  11  having core wires connected to the conductive terminals  100  and the ground terminal  101 , respectively; a cover  12  integrally connected to the terminal base  10  by a plurality of first screws  102 ; and a ground mechanism  13  for connecting the first screws  102  to the ground terminal  101 , allowing the first screws  102  to be grounded. 
     FIG. 2 illustrates a perspective dissection diagram of a terminal base with a ground mechanism in the power plug of the first embodiment of the invention; FIG. 3 illustrates a cross-sectional view of a terminal base with a ground mechanism in the power plug of the first embodiment of the invention. Referring to FIGS. 1,  2  and  3 , the ground mechanism  13  includes a first conductive member  130  such as a copper plate for connecting the first screws  102  to the ground terminal  101 . One end of the copper plate  130  is associated with the ground terminal  101 , and the other end thereof extends to screw holes  1020  for allowing the first screws  102  to penetrate therethrough. This makes the first screws  102  come into contact with the copper plate  130  when being screwed into the screw holes  1020 . 
     Furthermore, two of the first screws  102  are provided in the power plug  1 . The first conductive member  130  is an approximately M-shaped copper plate, wherein a central portion of the copper plate  130  is connected to the ground terminal  101 , and two ends thereof respectively extend to two screw holes  1020  where the first screws  102  can penetrate therethrough, so as to allow the first screws  102  to respectively screwed into the screw holes  1020  and come into contact with the copper plate  130 . 
     Moreover, the conductive terminals  100  and the ground terminal  101  of the terminal base  10  are in the form of a female power plug. 
     FIG. 4 illustrates a cross-sectional view of an upper part of a cover in the power plug of the first embodiment of the invention. Referring to FIGS. 2,  3  and  4 , the power plug  1  further comprises: a wire fixing mechanism  14  installed in the cover  12 , and two second screws  15 . The wire fixing mechanism  14  includes a press board  140  positioned at where the electric wire  11  passes thereby, and a clamping member  141  underneath the press board  140 . The two second screws  15  penetrate through the cover  12  and are screwed at two ends of the press board  140 , respectively. By screwing tight the second screws  15 , the press board  140  can be moved toward an inner wall of the cover  12 , allowing the electric wire  11  to be fixed and abut against the inner wall of the cover  12 , and to be firmly clamped by the clamping member  141 . 
     Besides the above first conductive member  130  for allowing the first screws  102  to be grounded, the ground mechanism  13  further includes a second conductive member  131  for interconnecting the two second screws  15 ; and a third conductive member  132  for connecting the first screws  102  to the second conductive member  131 , allowing the second screws  15  to be grounded via the second conductive member  131  and the first screws  102 . 
     The second conductive member  131  is a copper plate, two ends of which copper plate  131  respectively extend to second screw holes  150  for allowing the two second screws  15  to penetrate therethrough. This makes the second screws  15  comes into contact with the copper plate  131  when being screwed into the second screw holes  150 . 
     A central portion of the second conductive member  131  is exposed to one of the first screw holes  1020  used for screwing the first screws  102  therein. The third conductive member  132  is a metallic spring installed in the first screw hole  1020 . When one of the first screws  102  is screwed into the first screw hole  1020 , the metallic spring  132  is pressed, making one end thereof abut against the first screw  102 , and the other end of the metallic spring  132  adjoin the central portion of the second conductive member  131 . 
     FIG. 5 is a perspective dissection diagram showing another example of a terminal base with a ground mechanism in the power plug of the first embodiment of the invention. As shown in the drawing, besides the above-mentioned female power plug, the conductive terminals  100  and the ground terminal  101  of the terminal base  10  can also be in the form of a male power plug. 
     Second Preferred Embodiment 
     FIGS. 6,  7 ,  8  and  9  are respectively a top view, a side view, a front view and a back view of a power plug of a second embodiment of the invention; FIG. 10 is a perspective structural diagram showing an unassembled power plug of the second embodiment of the invention. Referring to FIGS. 6 to  10 , the power plug  2  of this embodiment comprises: a terminal base  20  having two conductive terminals  200  and a ground terminal  201 ; an electric wire  21  having core wires connected to the conductive terminals  200  and the ground terminal  201 , respectively; two covers  22  integrally connected to the terminal base  20 , which two covers  22  are capable of being coupled to each other by means of screws  24 , so as to enclose the conductive terminals  200  and the ground terminal  201  therein; and a ground mechanism  23  for connecting the screws  24  to the ground terminal  201 , so as to ground the screws  24 . 
     Furthermore, the ground mechanism  23  includes a conductive member  230  for interconnecting the first screws  24  and the ground terminal  201 . This conductive member  230  is a copper plate attached to an inner wall of one of the covers  22 , wherein one end of the copper plate  230  extends toward the ground terminal  201 , and is pressed to abut against the ground terminal  201  when the two covers  32  are engaged with each other, and the other end of the copper plate  230  extends to screw holes  240  for allowing the screws  24  to penetrate therethrough, whereby the screws  24  are made to come into contact with the copper plate  230  when being screwed into the screw holes  240 . 
     In particular, two of the screws  24  are adopted in this embodiment, and alternatively, the conductive member  230  can be an approximately T-shaped copper plate provided on the inner wall of one of the covers  22 . The vertical end of the T-shaped copper plate  230  extends toward the ground terminal  201 , and is pressed to abut against the ground terminal  201  when the two covers  32  are engaged with each other; the other two ends of the copper plate  230  extend to the screw holes  240 , allowing the two screws  24  to come into contact with the copper plate  230  when being respectively screwed into the screw holes  240 . 
     Third Preferred Embodiment 
     Illustrated in FIGS. 11 and 12 are respectively a top view and a cross-sectional view of a power plug of a third embodiment of the invention. Referring to FIGS. 11 and 12, the power plug  3  comprises: a terminal base  30  having a conductive terminal  300 ; an electric wire  31  having core wires connected to the conductive terminal  300  and a ground terminal  330 , respectively; a cover  32  integrally connected to the terminal base  30  by means of screws  320 ; a ground wire  33  having one end thereof connected to the ground terminal  330  inside the terminal base  30  and the cover  32 ; and a ground mechanism  34  for connecting the screws  320  to the ground terminal  330  of the ground wire  33 , so as to ground the screws  320 . 
     The power plug of the invention is characterized in the provision of a ground mechanism, which can solve a problem of electron ionization occurring in a conventional power plug as previously described, and further allow timbre quality of audio equipment to be effectively improved, whereby sounds generated from the audio equipment are clarified, especially for low bands to be more stable and sound. Moreover, in the use of the power plug of the invention, metal-induced interference with power or current passing through inside of the power plug and electric wires can be eliminated, allowing high quality of the clear original sounds to reappear. 
     In conclusion, the invention evidently provides positive and affirmative improvements in elevating and raising sound quality generated by the audio equipment. 
     The invention has been described using exemplary preferred embodiments. However, it is to be understood that the scope of the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangements. The scope of the claims, therefore, should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.