Note: Descriptions are shown in the official language in which they were submitted.
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GROUNDING APPARATUS FOR A SAFETY GROUNDED TREE
RELATED APPLICATIONS
[0001] This application is a continuation-in-part of and claims priority to
U.S. Patent Application
Serial No. 14/317,291, entitled "Safety Grounded Tree" filed June 27, 2014,
the contents of
which is herein incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention generally relates to artificial lighted trees.
Specifically,
embodiments of the present invention provide for a decorative lighted
Christmas tree with power
routed through the trunk of the tree and three-wire safety grounding. The
system provides ways
for connecting hot, neutral, and ground wires from a power supply cord to the
decorative lighted
Christmas tree.
BACKGROUND OF THE INVENTION
[0003] Seasonal lights, such as those used in conjunction with Christmas
trees, are well known in
the art. These seasonal lights generally use two-wire conductors to provide
power to each of the
light bulbs on a particular strand. Since insulation covers the entire length
of the wire and plug,
risk of shock is minimal so grounding is not a major issue.
[0004] However, artificial pre-lighted Christmas trees, where the seasonal
lights are incorporated
on or with the tree, have become a popular alternative to both live trees and
unlighted artificial
trees. These trees are usually sectional for easy storage, with some lighted
trees routing power
for the lights up through the trunk of the tree with electrical connectors
built into the ends of each
tree section to distribute power to each section. This mechanism, although
convenient, brings
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with it the risk of exposed conductors at every electrical junction. If these
exposed conductors
accidentally make contact with any other portion of the artificial tree, there
is a risk of electric
shock and other undesirable electrical dangers (e.g., fire).
[0005] Therefore, there is a need in the art for a lighted artificial
Christmas tree with a 3-wire
safety ground connection. These and other features and advantages of the
present invention will
be explained and will become obvious to one skilled in the art through the
summary of the
invention that follows.
SUMMARY OF THE INVENTION
[0006] Accordingly, it is an object of the present invention to provide an
artificial lighted tree
with power routed through a hollow trunk and three-wire electrical grounding,
where the trunk
itself is conductive and grounded.
[0007] According to an embodiment of the present invention, a power cord
comprises: a male
end comprising a hot prong, a neutral prong, and a ground prong wherein the
male end is
configured to plug into a three-prong grounded outlet; and a female end
comprising: a first
surface on the distal end of the power cord, a second surface non-coplanar to
said first surface, a
female electrical connector on said first end configured to receive a standard
male two-prong
non-polarized NEMA 1 plug, a ground connection extending from the second
surface of said
female end, said ground connection configured to attach to a ground point
without blocking
access to the female electrical connector.
[0008] According to an embodiment of the present invention, The power cord of
claim 1 wherein
the ground connection is a flexible ground wire extending from the female end,
the ground wire
terminated with an electrical connector configured to make an electrical
connection to a ground
point.
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[0009] According to an embodiment of the present invention, the ground
connection is a rigid
ground tab extending from the female end and configured to make an electrical
connection to a
ground point.
[0010] According to an embodiment of the present invention, the female
electrical connector is
polarized.
[0011] According to an embodiment of the present invention, the female end
further comprises: a
concave rounded contour allowing the female end to lie flush against a convex
rounded surface.
[0012] According to an embodiment of the present invention, the female end
further comprises
an attachment means configured to secure the female end to a device while
simultaneously
creating a ground electrical connection to the device.
[0013] According to an embodiment of the present invention, the power cord
further comprises a
foot switch configured to toggle on and off an electrical signal provided to
the female end of the
power cord.
[0014] According to an embodiment of the present invention, an electrical
apparatus comprises:
a three-prong safety-grounded power plug; a molded electrical box having a
contoured back
configured to sit flush against a device to which the molded electrical box is
to be attached, the
device having a corresponding contour; a hot wire, and a neutral wire, each
electrically
connected to the power plug and each entering the molded electrical box; a
ground wire,
electrically connected to a ground prong of the power plug; an attachment
means for securing the
electrical box to the device; an access panel configured to provide access to
the inside of the
electrical box; a fuse holder inside the electrical box, the fuse holder
electrically connected in
line with the hot wire.
[0015] According to an embodiment of the present invention, the attachment
means is
conductive and configured to make a ground connection with a ground point on
the device; and
the ground wire is electrically connected to the attachment means.
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[0016] According to an embodiment of the present invention, the ground wire
terminates in an
electrical connector configured to make an electrical connection with a ground
point of the
device.
[0017] According to an embodiment of the present invention, the hot wire and
the neutral wire
exit the box and enter the device through a securing grommet.
[0018] According to an embodiment of the present invention, the electrical
apparatus of claim 8
further comprising a lighted artificial tree having a conductive hollow trunk
body wherein the
device is the lighted artificial tree.
[0019] According to an embodiment of the present invention, a lighted
artificial tree comprises: a
hollow body having an electrically conductive wall; one or more inner
electrical conductors
situated inside the hollow body; one or more side electrical connectors
accessible from the
outside of the hollow body and electrically connected to the inner electrical
conductors; a three-
prong safety ground electrical cord comprising a ground conductor electrically
connected to the
electrically conductive wall of the hollow body.
[0020] According to an embodiment of the present invention, the three-prong
safety ground
electrical cord further comprises: a male end configured to plug into a power
outlet; a female end
configured to receive a standard two-prong non-polarized electrical plug;
wherein the ground
conductor extends from the electrical cord and terminates in a ground
electrical connector
configured to attach to the electrically conductive wall of the hollow body.
[0021] According to an embodiment of the present invention, the ground
electrical connector is a
ring terminal.
[0022] According to an embodiment of the present invention, the ground
electrical connector is a
conductive rigid tab.
[0023] According to an embodiment of the present invention, the female end is
molded to fit the
outer contour of the hollow body.
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[0024] The foregoing summary of the present invention with the preferred
embodiments should
not be construed to limit the scope of the invention. It should be understood
and obvious to one
skilled in the art that the embodiments of the invention thus described may be
further modified
without departing from the spirit and scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 shows a tree-mounted electrical box providing an interface
between an electrical
cord, a fuse, and a ground connection according to an embodiment of the
present invention.
[0026] FIG. 2 shows a tree-mounted electrical box with a grounding base plate
providing an
interface between an electrical cord, a fuse, and a ground connection
according to an
embodiment of the present invention.
[0027] FIG. 3 shows a tree-mounted electrical box with an alternate access
door, providing an
interface between an electrical cord, a fuse, and a ground connection
according to an
embodiment of the present invention.
[0028] FIG. 4 shows a power cord and a powered decorative tree configured to
connect to the
power cord through a grounding point on the powered decorative tree according
to an
embodiment of the present invention.
[0029] FIG. 5 shows a power cord with a female end which attaches to a powered
decorative tree
through the grounding point and is molded to fit the contour of the tree trunk
according to an
embodiment of the present invention.
[0030] FIG. 6 shows a schematic diagram of a system for grounding a powered
decorative tree
with a foot switch for controlling power to the tree according to an
embodiment of the present
invention.
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[0031] FIG. 7 shows a schematic diagram of a system for grounding a powered
decorative tree
according to an embodiment of the present invention.
DETAILED SPECIFICATION
[0032] The present invention generally relates to artificial lighted trees.
Specifically,
embodiments of the present invention provide for a decorative lighted
Christmas tree with power
routed through the trunk of the tree and three-wire safety grounding. The
system provides ways
for connecting hot, neutral, and ground wires from a power supply cord to the
decorative lighted
Christmas tree.
[0033] In general, the system described herein provides for a three prong
safety grounded power
cord to be attached to and provide a safety ground connection for a powered
decorative tree. A
grounding connection from the power cord is attached and electrically
connected to the trunk of
the powered decorative tree. The trunk is preferably electrically conductive
or has an electrically
conductive wall. Inside the trunk are electrical conductors for providing
power to the lights of the
powered decorative tree. According to one embodiment, these electrical
conductors make hot
and neutral connections by a standard two-prong plug that plugs into a female
end of the three
prong safety grounded power cord. Alternatively the hot and neutral conductors
can by directly
connected to the hot and neutral conductors of the three prong safety grounded
power cord
through electrical contact points of the powered decorative tree. Fuse
connections are provided
through a fuse box that the hot wire passes through or fuses are incorporated
into a standard
fused two-prong plug. The back side of the female end of the safety grounded
power plug or the
fuse box is molded to sit flush against the trunk of the powered decorative
tree for more stable
and safe attachment. A foot switch is also incorporated into the power cord to
allow power to the
powered decorative tree to be controlled without unplugging the power cord
from the wall.
[0034] According to an embodiment of the present invention, Fig. I shows a
molded electrical
box 101 with a flange 104 on each side for securing the molded electrical box
to the rounded
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trunk of a decorative lighted Christmas tree. A three-prong safety grounded
plug 102 provides
hot wire 106, neutral wire 106, and ground wire 108 to the molded electrical
box 101. A notched
access panel 103 slides out providing access for placing a fuse on at least
the hot wire 106.
Besides connecting the ground wire 108 to the decorative lighted Christmas
tree, there are
various possible connections that can be made in and around the molded
electrical box 101
including, but not limited to: connecting the neutral wire 107 and ground
wires 108 to each other
and fusing the hot wire 106; fusing both the hot wire 106 and the neutral wire
107; or passing
both the hot wire 106 and neutral wire 107 through the electrical box without
fusing when fusing
is done elsewhere on the tree. One or ordinary skill in the art would
recognize that any method of
fusing and grounding the wires could be used without departing from the spirit
and scope of the
present invention.
[0035] According to an embodiment of the present invention, A rounded back 105
of the
electrical box 101 is molded to fit the curvature of the decorative lighted
Christmas tree. This
allows the flanges 104 and the molded back 105 of the electrical box 101 to
sit flush against the
decorative lighted Christmas tree and provide a secure connection that is less
likely to shift or
break from being bumped or nudged during assembly disassembly or general use
of the
decorative lighted Christmas tree. In place of the flanges 104, the electrical
box can also be
attached to the decorative lighted Christmas tree by way of an adhesive, glue,
welding, or any
other attachment means. One of ordinary skill in the art would understand that
any kind of
attachment means may be used to attach the electrical box to the decorative
lighted Christmas
tree without departing from the spirit and scope of the present invention.
[0036] According to an embodiment of the present invention, the ground wire
108 is connected
to the conductive trunk of the decorative lighted Christmas tree by a ring
terminal 110
electrically connected to the end of the ground wire 108. A tamper-proof screw
109 attaches to
the conductive trunk of the decorative lighted Christmas tree through the ring
terminal 110 and a
star washer 111. The ground connection may also be made by soldering, welding,
screw-down
terminals, blade connectors, or any other kind of attachment means which makes
an electrical
connection. In an alternate embodiment, the ground wire bypasses the molded
electrical box and
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connects directly to a ground point on the decorative lighted Christmas tree.
One or ordinary skill
in the art would recognize that any kind of electrical attachment means may be
used without
departing from the spirit and scope of the present invention.
[0037] According to an embodiment of the present invention, Fig. 2 shows a
molded electrical
box 101 very similar to Fig. 1 except the flanges 104 are formed from a single
piece of metal that
extends through the back of the electrical box 101. The flanges 104 extend
outside the electrical
box 101, exposing a mounting hole which connects to the conductive trunk of
the decorative
lighted Christmas tree through a star washer 111. The ground wire 108 is
welded 112 or
otherwise electrically connected to the metal flanges 104 inside the
electrical box 101. The
preferred method of attaching the electrical box 101 to the decorative lighted
Christmas tree
trunk is by putting a tamper-proof screw through each flange into a bare metal
attachment site on
the trunk using a star washer. The electrical box 101 can also be attached to
the trunk by
welding, bolts, adhesives, straps, or any other kind of attachment means.
Preferred attachment
means would also produce an electrical connection between the trunk and the
ground wire 108
electrically connected to the flanges 104. One or ordinary skill in the art
would recognize that
any attachment means could be used without departing from the spirit and scope
of the present
invention.
[0038] According to an embodiment of the present invention, Fig 3 shows an
alternate
embodiment of the electrical box 101. The primary difference in the electrical
box 101 of Fig. 3
is the access panel 103, which opens on a hinge and snaps shut rather than
sliding out of a slot to
reveal the fuse. The fuse 113 fits into a fuse holder 114 inside the
electrical box 101. As in Fig.
1, the ground wire 108 passes through the electrical box 101 and fastens to
the conductive trunk
of the decorative lighted Christmas tree via a tamper-proof screw 109, a ring
terminal 110, and a
star washer 111. This creates a ground connection from the trunk to the ground
wire 108 which is
connected to the ground prong on the three-prong safety grounded plug 102.
[0039] According to an alternate embodiment of the present invention, Fig 4
shows a power cord
with a 3-prong safety grounded plug 102 on the male end and a modified female
socket on the
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female end 420. The modified female socket may be polarized or non-polarized.
Both polarized
and non-polarized sockets are configured to accept a standard NEMA 1 two-prong
non-polarized
plug. The modified female socket is positioned on a first surface of the
female end 420 and a
second surface of the female end 420 is non-coplanar to the first surface. The
term non-coplanar
here can refer to any portion of the female end which is not on the plane
defined by the face of
the female socket on the first surface. Instead of having a rounded socket to
receive a ground
prong on the first surface, a ground wire 108 extends out from the second
surface of the modified
female socket and is terminated with a ring terminal 110. This ring terminal
110 is attached to a
bare metal ground point 431 on the decorative lighted Christmas tree trunk 430
with a tamper-
proof screw 109 and a star washer 111. The modified female socket at the end
of the power cord
is configured to receive a standard plug 433 often used in Christmas tree
lights. The Conductors
434 from the standard plug 433 then pass into the inside of the trunk 430
through a securing
grommet 432.
[0040] In the preferred embodiment the standard plug 433 is non-polarized
because these plugs
are commonly used in Christmas tree lighting and readily available. In a non-
polarized plug, both
the hot and neutral wires pass through fuses because there is no guarantee
that the plug will be
connected in a particular orientation. Alternatively, the standard plug 433
may be a polarized
type. When the standard plug 433. is polarized, a single fuse is used on the
hot wire, and the
neutral wire may be grounded to the trunk of the decorative lighted Christmas
tree at one or more
places within the decorative lighted Christmas tree. Alternatively, a fuse may
be placed in the 3-
prong safety grounded plug 102 so that the fuse is electrically connected in
line with the hot
wire. In this case, only a single fuse is needed. For safety, the grounded
plug 102 can be
configured with a sliding door providing access to the fuse. The sliding door
only slides open
when the grounded plug is not plugged into a female socket.
[0041] According to an alternate embodiment of the present invention, Fig 5
shows a different
version of the power cord with a three-prong safety grounded plug 102 on the
male end and a
modified female socket on the female end 420. On the modified female socket of
Fig. 5, the
ground wire 108 is replaced with a ground prong 508. According to one
embodiment the ground
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prong is bent at two 90 degree angles so that it lines up flush with the trunk
430 and the molded
base 521 of the modified female socket. The molded base 521 of the female end
420 is curved to
fit the rounded trunk of the decorative lighted Christmas tree. An important
feature of the power
cord depicted in both Fig. 4 and Fig. 5 is that the ground connection can be
made independently
of the hot and neutral connection (through the standard plug) without
interfering with the ability
of the standard plug to be plugged in and removed from the female end 420 of
the power cord.
One way of achieving this is by placing the ground connection on a surface
other than the first
surface where the female socket is placed.
[0042] According to an alternate embodiment of the present invention, Fig 6
shows the power
cord of Fig. 5 attached to a bare metal ground point 431 on the conductive
trunk 430 of the
decorative lighted Christmas tree by a tamper-proof screw 109, and a star
washer 111.
Alternatively, welding, soldering, a screw-down terminal, or other attachment
means can also be
used to attach and electrically connect the ground prong 508 to the trunk 430.
The ground prong
allows the female end 420 to be secured to the trunk while simultaneously
making a ground
connection to the trunk. One or ordinary skill in the art would recognize that
a ground prong 508
of any shape may be attached by any means to the trunk 430 without departing
from the spirit
and scope of the present invention. Fig. 6 also shows a foot switch 640 in
line with the power
cord. The foot switch 640 contains a push-button toggle switch which controls
power to the
decorative lighted Christmas tree. A non-polarized two-fused plug 433 plugs
into the modified
female socket 420 and the power wires 434 enter the trunk of the decorative
lighted Christmas
tree through a securing grommet 432. Power is distributed within the tree to
various sockets,
connectors, and/or light strings on the decorative lighted Christmas tree.
[0043] The optional foot switch 640 allows for controlling the lights. In
other embodiments, the
control of the lighting of the tree may be controlled by one or more control
elements, such as a
switch, a selector knob, an indicator panel, or any other human interface
device (HID) or any
combination thereof. One of ordinary skill in the art would appreciate that
there are numerous
types of control elements that could be utilized with embodiments of the
present invention, and
embodiments of the present invention are contemplated for use with any type of
control element.
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According to another embodiment of the present invention, the foot switch may
include
electronics which convert the high voltage AC to low voltage DC and pass the
ground
connection through to the modified female socket 420 to allow for proper
grounding even when
high voltage AC is not used to run the lights on the decorative lighted
Christmas tree.
[0044] According to another embodiment of the present invention, Fig. 7 shows
a schematic
diagram the safety grounded decorative lighted Christmas tree. The three-prong
safety grounded
plug 702 sends electrical conductors through a single pole switch 740. In one
embodiment this
switch is the foot switch 640 shown in Fig. 6. An electrical connector 701 is
then grounded to the
conductive trunk 730, creating a ground connection from the conductive trunk
730 to the ground
wire 708 through an attachment means 709, such as a screw. The hot wire 706,
and neutral wire
707 pass through the electrical connector 701 to a corresponding connector 733
that houses two
fuses 713. Alternatively the fuses 713 can be housed in the electrical
connector 701, or elsewhere
on the tree. The hot wire 706 and neutral wire 707 then pass into the trunk
730 through a
securing grommet 732 to route power throughout the inside of the trunk. Side
connectors 750
outside the trunk are connected to the hot 706 and neutral 707 wires that pass
through securing
grommets 732 from inside the tree trunk 730 to outside the tree trunk 730. The
side electrical
connectors 750 may be as simple as a wire, electrically connected to the wires
inside the tree
trunk 730, and merely passing through a hole in the trunk 730 to the lights on
the tree, or it may
be a complex detachable multi-conductor connector as depicted in this
application's parent
application, U.S. Patent Application Serial No. 14/317,291, entitled "Safety
Grounded Tree"
filed June 27, 2014. One of ordinary skill in the art would appreciate that
there are numerous
types of side electrical connector that could be utilized with embodiments of
the present
invention, and embodiments of the present invention are contemplated for use
with any
appropriate type of side electrical connector.
[0045] One or ordinary skill in the art would recognize that wires are not
necessary, and any
conductor can be used, including, but not limited to, printed circuits,
conductive paints,
conductive liquids, or ionized gases. Embodiments of the present invention may
incorporate one
or more of these conductors in lieu of or in conjunction with the wires.
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[0046] While multiple embodiments are disclosed, still other embodiments of
the present
invention will become apparent to those skilled in the art from this detailed
description. The
invention is capable of myriad modifications in various obvious aspects, all
without departing
from the spirit and scope of the present invention. Accordingly, the drawings
and descriptions
are to be regarded as illustrative in nature and not restrictive.
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