GB2328090A

GB2328090A - Angle adjustable electrical plug

Info

Publication number: GB2328090A
Application number: GB9716748A
Authority: GB
Inventors: Jonie Chou
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-08-08
Filing date: 1997-08-08
Publication date: 1999-02-10
Anticipated expiration: 2017-08-08
Also published as: GB2328090B; GB9716748D0

Abstract

An angle adjustable electrical plug includes an insulative bottom shell 5 which holds a metal sleeve 12 at the centre, a first annular metal cushion 14 spaced around the metal sleeve and a second annular metal cushion 16 spaced around the first annular metal cushion, an insulative upper shell 1 fastened to the bottom shell by screws to hold a three-wire electrical cable 2 in therebetween, permitting the three wires of the electrical cable to be respectively connected to the metal sleeve and the annular metal cushions, a rotary cap 3 revolvably mounted within the bottom shell to hold a first metal contact blade 32 connected to the metal sleeve by a fuse 42 and a metal clamping frame 35, a second metal contact blade 33 disposed in contact with the first annular metal cushion, and a third metal contact blade 34 disposed in contact with the second annular metal cushion.

Description

ANGLE ADJUSTABLE ELECTRICAL PLUG BACKGROUND OF THE INVENTION The present invention relates to electrical plugs, and more specifically to an angle adjustable electrical plug which can be conveniently adjusted to the change the positions of the metal contact blades so as to fit different installation conditions.

The metal contact blades of a regular electrical plug are commonly disposed in line with the electrical cable thereof. Therefore, the electrical cable must be bent in a particular direction when the electrical plug is installed in an electrical socket in a narrow area or behind a piece of furniture. However, it is possible for the insulator ends to be broken if the electrical cable is deformed, thereby causing a short circuit. U.S. Pat. No.

4,927,376, issued to Dickle, discloses an electrical plug adapted for installation in a narrow space. However, this structure of electrical plug fits only one particular direction.

SUMMARY OF THE INVENTION The present invention has been accomplished to provide an electrical plug which eliminates the aforesaid problems. According to the preferred embodiment of the present invention, the angle adjustable electrical plug comprises an insulative bottom shell which holds a metal sleeve at the center, a first annular metal cushion spaced around the metal sleeve and a second annular metal cushion spaced around the first annular metal cushion, an insulative bottom shell fastened to the upper shell by screws to hold a threewire electrical cable in therebetween, permitting the three wires of the electrical cable to be respectively connected to the metal sleeve and the annular metal cushions, a rotary cap revolvably mounted within the bottom shell to hold a first metal contact blade connected to the metal sleeve by a fuse and a metal clamping frame, a second metal contact blade disposed in contact with the first annular metal cushion, and a third metal contact blade disposed in contact with the second annular metal cushion. Further, spring members may be provided to impart an upward pressure to the first annular metal cushion and the second annular metal cushion, causing them to be firmly retained in contact with the second metal contact blade and the third metal contact blade. Locating rods may be provided at the rotary cap to hold down the first annular metal cushion and the second annular metal cushion.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an exploded view of an angle adjustable electrical plug according to the present invention; Fig. 2 is a sectional view of the angle adjustable electrical plug shown in Figure 1; Fig. 3 is another sectional view of the present invention, showing the angular position of the rotary cap adjusted; and Fig. 4 is an elevational view of the angle adjustable electrical plug shown in Figure 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to Figures from 1 to 4, an angle adjustable electrical plug in accordance with the present invention is generally comprised of an upper shell 1, an electrical cable 2, a rotary cap 3, a fuse assembly 4, and a bottom shell 5.

The upper shell 1 is a flat, electrically insulative covering fitting over the bottom shell 5, comprising an upright stub tube 11 on the inside, the upright stub tube 11 having a side opening 111. A metal sleeve 12 is mounted within the upright stub tube 11. A first upright annular flange 13 is located on the inside of the upper shell 1 around the upright stub tube 11, the first upright annular flange 13 having a first side opening 133 corresponding to the side opening 111 of the upright stub tube 11 and a second side opening 134. A first annular groove 131 is defined by the first upright annular flange 13 and the upright stub tube 11. A plurality of first upright rods 132 and first inside locating pins 135 are disposed in the first annular groove 131. A first annular metal cushion 14 is mounted within the first annular groove 131 and retained in place by the first upright rods 132 and the first inside locating pins 135, the metal cushion 14 having a connecting tip 141. A second upright annular flange 15 is located on the inside around the first upright annular flange 13, the second upright annular flange 15 having a first side opening 153 and a second side opening 154. A second annular groove 151 is defined between the second upright annular flange 15 and the first upright annular flange 13. A plurality of second upright rods 152 and second inside locating pins 155 are disposed in the second annular groove 151. A second annular metal cushion 16 is mounted within the second annular groove 151 and is retained in place by the second upright rods 152 and the second inside locating pins 155, the second annular metal cushion 16 having a connecting tip 161. A plurality of upright mounting rods 17 are located on the inside of the upper shell 1 near the border and adapted for fastening to the bottom shell 5, each upright mounting rod 17 defining a screw hole 171. An upright clamping plate 18 is raised from the upper shell 1 on the inside near the border and adapted for holding down the electrical cable 2.

The electrical cable 2 is comprised of a hot line 21, a neutral line 22, and a grounding line 23. A mounting block 24 is provided at one end of the electrical cable 2 and secured to the upper shell 1 and the bottom shell 5. The hot line 21 is inserted through the second side opening 154 of the second upright annular flange 15 and the first side opening 133 of the first upright annular flange 13 and the side opening 111 of the upright stub tube 11, and then connected to the metal sleeve 12. The neutral line 22 is inserted through the second side opening 134 of the first upright annular flange 13, and then connected to the connecting tip 141 of the first annular metal cushion 14. The grounding line 23 is inserted through the first side opening 153 of the second upright annular flange 15, and then connected to the connecting tip 161 of the second annular metal cushion 16.

The rotary cap 3 is a circular, electrically insulative plate comprising a locating block 31 at its back side, two mounting holes 316 defined in the locating block 31, a first slot 311, a second slot 312 and a third slot 313, a plurality of locating rods 317 disposed at its back side outside the locating block 31 and adapted to hold down the first annular metal cushion 14 and the second annular metal cushion 16, a front open chamber 315, an outward annular flange 36 raised around the periphery and coupled to the bottom shell 5, a first metal contact blade 32 mounted in the first slot 311, a second metal contact blade 33 mounted in the second slot 312, a third metal contact blade 34 mounted in the third slot 313, and a metal connecting frame 35 having a substantially U-shaped clamping portion 351 inserted through the mounting holes 316 into the front open chamber 315 and a front tip 352 forced into contact with the metal sleeve 12. The first metal contact blade 32 has a L-shaped tail 321 and a clamping strip 322 at one end. When the first metal contact blade 32 is mounted in the first slot 311, the L-shaped tail 321 and the clamping strip 322 are received in the front open chamber 315. The second metal contact blade 33 has an arched tail 331 retained in contact with the first annular metal cushion 14. The third metal contact blade 34 has an arched tail 341 retained in contact with the second annular metal cushion 16.

The fuse assembly 4 comprises a substantially T-shaped fuse holder 41 having a fuse hole 411, and a cartridge fuse 42 mounted in the fuse hole 411. The fuse assembly 4 is mounted in the front open chamber 315 of the rotary cap 3, and then sealed. When the fuse assembly 4 is installed, the two opposite terminals 421 of the fuse 42 are respectively connected to the L-shaped tail 321 and clamping strip 322 of the first metal contact plate 32 and the U-shaped clamping portion 351 of the metal connecting frame 35. If there is an overcurrent passing through the first metal contact blade 32, the fuse 42 is immediately burnt out to break the circuit. When the fuse holder 41 is removed from the front open chamber 315 of the rotary cap 3, the fuse 42 can then be replaced with a new one.

The bottom shell 5 is an insulative covering fitting over the upper shell 1, comprising a circular open chamber 51 which receives the outward annular flange 36 of the rotary cap 3, a plurality of upright mounting rods 52, each upright mounting rod 52 defining a respective axial through hole 521 respectively connected to the screw holes 171 of the upright mounting rods 17 of the upper shell 1 by screws 53, and a cable hole 54 at one side for matching with the upright clamping plate 18 of the upper shell 1 to hold down the mounting block 24 of the electrical cable 2.

Further, a plurality of spring members 19 are respectively mounted around the first upright rods 132 and the second upright rods 152 to impart an outward pressure to the first annular metal cushion 14 and the second annular metal cushion 16, causing the first annular metal cushion 14 and the second annular metal cushion 16 to be retained in close contact with the arched tail 331 of the second metal contact blade 33 and the arched tail 341 of the third metal contact blade 34.

Referring to Figures 1 and 2 again, the assembly process of the angle adjustable electrical plug is simple and outlined hereinafter. The first metal contact blade 32, the second metal contact blade 33 and the third metal contact blade 34 are respectively inserted into the first slot 311, second slot 312 and third slot 313 of the rotary cap 3, then fuse assembly 4 is mounted in the front open chamber 315 of the rotary cap 3 and connected between the first metal contact blade 32 and the metal connecting frame 35, and then the rotary cap 3 is rotatably mounted in the circular open chamber 51 of the bottom shell 5. The spring members 19 are respectively mounted on the upright rods 132; 152, and then the metal sleeve 12 and the annular metal cushions 14;16 are respectively fastened to the hot line 21, neutral line 22, and grounding line 23 of the electrical cable 2 and mounted in the upright stub tube 11, first annular groove 131 and second annular groove 151 of the upper shell 1. Then, the upper shell 1 is fastened to the bottom shell 5 by connecting the upright mounting rods 52 of the bottom shell 5 to the upright mounting rods 17 of the upper shell 1 by screws 53, permitting the electrical cable 2 to extend out of the bottom shell 5 and the upper shell 1 through the gap between the cable hole 54 of the bottom shell 5 and the upright clamping plate 18 of the upper shell 1.

Referring to Figures 2 and 3 again, when the rotary cap 3 is turned within the circular open chamber 51 of the bottom shell 5 through any desired angle, the arched tail 331 of the second metal contact blade 33 is maintained in contact with the first annular metal cushion 14, the arched tail 341 of the third metal contact blade 34 is maintained in contact with the second annular metal cushion 16, and the first metal contact blade 32 and the metal clamping frame 35 are maintained in contact with the two terminals 421 of the fuse 42, and the front tip 352 of the metal clamping frame 35 is forced into contact with the metal sleeve 12. Therefore, the rotary cap 3 can be turned within the circular open chamber 51 of the bottom shell 5 to change the positions of the metal contact blades 33; 34 to fit the angular position of any electrical socket.

While only one embodiment of the present invention has been shown and described, it will be understood that various modifications and changes could be made thereunto without departing from the spirit and scope of the invention disclosed.

Claims

1. An angle adjustable electrical plug, comprising: an electrically insulative upper shell, said upper shell comprising an upright stub tube on the inside, the upright stub tube having a side opening, a metal sleeve mounted within said upright stub tube, a first upright annular flange around said upright stub tube and having a first side opening corresponding to the side opening of said upright stub tube and a second side opening, a first annular groove defined by said first upright annular flange and said upright stub tube, a plurality of first upright rods and first inside locating pins disposed in said first annular groove, a first annular metal cushion mounted within said first annular groove and retained in place by said first upright rods and said first inside locating pins, said first metal cushion having a connecting tip, a second upright annular flange around said first upright annular flange, said second upright annular flange having a first side opening and a second side opening, a second annular groove defined between said second upright annular flange and said first upright annular flange, a plurality of second upright rods and second inside locating pins disposed in said second annular groove, a second annular metal cushion mounted within said second annular groove and retained in place by said second upright rods and said second inside locating pins, said second annular metal cushion having a connecting tip, and an upright clamping plate adapted for holding down an electrical cable; an electrical cable, said electrical cable comprising a mounting block secured to said upright clamping plate of said upper shell, a hot line inserted through the second side opening of said second upright annular flange and the first side opening of said first upright annular flange and the side opening of said upright stub tube and then connected to said metal sleeve, a neutral line inserted through the second side opening of said first upright annular flange and then connected to the connecting tip of said first annular metal cushion, and a grounding line inserted through the first side opening of said second upright annular flange and then connected to the connecting tip of said second annular metal cushion; a circular, electrically insulative rotary cap, said rotary cap comprising a locating block at a back side thereof, two mounting holes defined in said locating block, a first slot, a second slot and a third slot, a plurality of locating rods disposed at its back side outside said locating block and adapted to hold down said first annular metal cushion and said second annular metal cushion, a front open chamber, an outward annular flange, a first metal contact blade mounted in said first slot, a second metal contact blade mounted in said second slot, a third metal contact blade mounted in said third slot, and a metal connecting frame having a substantially U-shaped clamping portion inserted through said mounting holes into said front open chamber and a front tip forced into contact with said metal sleeve, said first metal contact blade having a L-shaped tail and a clamping strip at one end, said second metal contact blade having an arched tail retained in contact with said first annular metal cushion, said third metal contact blade having an arched tail retained in contact with said second annular metal cushion; a fuse assembly having a substantially T-shaped fuse holder mounted in the front open chamber of said rotary cap and a fuse mounted in said fuse holder and connected between the L-shaped tail and clamping strip of said first metal contact plate and the Ushaped clamping portion of said metal connecting frame; and an electrically insulative bottom shell fit over said upper shell, said bottom shell comprising a circular open chamber which receives the outward annular flange of said rotary cap, and a cable hole at one side matched with the upright clamping plate of said upper shell to hold down the mounting block of said electrical cable.

2. An angle adjustable electrical plug, comprising an insulative bottom shell which holds a metal sleeve at the centre, a first annular metal cushion spaced around the metal sleeve and a second annular metal cushion spaced around the first annular metal cushion, an insulative bottom shell fastened to the upper shell by screws to hold a threewire electrical cable in therebetween, permitting the three wires of the electrical cable to be respectively connected to the metal sleeve and the annular metal cushions, a rotary cap rotatably mounted within the bottom shell to hold a first metal contact blade connected to the metal sleeve by a fuse and a metal clamping frame, a second metal contact blade disposed in contact with the first annular metal cushion, and a third metal contact blade disposed in contact with the second annular metal cushion.

3. An electrical plug according to Claim 1, wherein a plurality of spring members are respectively mounted around said first upright rods and second upright rods of said upper shell to force said first annular metal cushion and said second annular metal cushion into close contact with the arched tail of said second metal contact blade and the arched tail of said third metal contact blade respectively.

4. An electrical plug according to Claim 1 or 2, wherein said rotary cap has a plurality of locating rods adapted for hold down said first annular metal cushion and said second annular metal cushion.

5. An electrical plug according to any preceding claim, wherein said upper shell and said bottom shell are fastened together by screws.

6. An electrical plug according to Claim 1, wherein said fuse holder is detachably mounted in the front open chamber of said rotary cap.

7. An electrical plug, substantially as described with reference to, or as shown in, the drawings.