Note: Descriptions are shown in the official language in which they were submitted.
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TITLE: PLUG LOCK FOR ELECTRICAL APPLIANCES
FIELD OF THE INVENTION
The present invention re:Lates in general to the
locking of an electrical plug in an electrical receptacle
and has particular application for wall suspended
electrical appliances .
BA K<~ROUND OF THE INVENTION
Electrical heater fans have become more and more
popu7_ar over time. On.e of the reasons for their popularity
is that rather than being dedicated to a specific location
they can be moved from. room to room.
In recent years electrical heater fans have been
made such that they ca.n plug directly into and be suspended
from an electrical outlet on a wall. This eliminates the
requirement for floor space for the heater fan and also
raises the heater fan to a position where the flow of
heater air from the fan is off of the floor.
To date, wall mounted heater fans include a
relatively standard electric plug which is supported on the
back surface or casing of the heater fan. The heater fan
is then simply pushed by its plug into the electrical
outlet where its plug holds it suspended from the wall.
However, because there is no interlock, other than the
standard fit between the plug and the receptacle, the plug
on the heater fan is not capable of supporting a
substantial load. Therefore, the known wall mounted heater
fans are relatively light in weight having a maximum
operaaing capacity of 1200 watts. A ground supported
heater fan on the other hand typically has a maximum
operating capacity of 1500 watts and is therefore, capable
of producing more heat than the wall mounted heater fan.
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~~RY OF THE INVENTION
The present invention relates to a locking member
which is releasably lockable within a standard wall fitted
electrical receptacle and can for example be used in a
suspension system for a wall mounted electrical appliance
such as a heater fan or the like.
The locking member itself has an insulated body
port__on presenting first and second slot fitting prongs and
a ground opening fitting post arranged in a triangular
pattern with the prong's so that the locking member fits
into a standard electrical receptacle. The post of the
locking member is adjustable between a receptacle insertion
position and a receptacle locked in position by a control
member rotatably supported by the insulated body portion of
the 7_ocking member .
The locking member can be used in association with
a mounting bracket for an electrical appliance such as a
heater fan and is capable of supporting a substantial load
such that the heater fan can be of a size to operate at up
to 1~~00 watts of power.
BRIEF' DESCRIPTION OF THE DRAWINGS
The above as well as other advantages and features
of the present invention will be described in greater
detail according to the preferred embodiments of the
present invention in which:
Figure 1 is a perspective view of a heater fan
suspE~nded from a wall by a mounting assembly behind the
heatE~r fan according to a preferred embodiment of the
present invention;
Figure 2 is a rear perspective view of the heater
fan of Figure 1;
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Figure 3 is an enlarged a_xploded perspective view
show_~ng the bracket mount over the electrical outlet and
the bracket mount for the bracket used to suspend the
heatE~r fan of Figure 1;
Figure 3a is an exploded perspective view showing
the Name bracket as found in Figure 3 with a slightly
modified bracket mount. for an electrical outlet different
from that found in Figure 3;
Figure 4 is a rear view of the bracket of Figures 3
and _i a ;
Figure 5 is a :bottom view of the operating part of
the plug lock from the bracket mount of Figure 3;
Figure 6 is a side view of the part shown in Figure
5;
Figure 7 is a sectional view through the housing
used to receive the operating part Figures 5 and 6;
of
Figure 8 is a top view of the housing shown in
Figure 7 ;
Figure 9 is a 'top view of the main plate of the
bracl~:et mount of Figure 3 without plug lock in
the
position;
Figure 10 is a sectional view of the plate of
Figure 9 when fitted with the plug ck;
lo
Figure 11 is a sectional view of the bracket mount
similar to Figure 10 but showing the plug lock in a
different operating position;
Figure 12 is a bottom view of the bracket mount
of
Figure 3 in the receptacle insertion position;
Figure 13 is a further bottom view of the bracket
mount, of Figure 3 with the plug :lockin the receptacle
locked in position;
Figure 14 is a bottom view of the bracket mount
of
Figure 3a;
Figure 15 is a sectional view of the bracket and
bracket mount of Figure 3 when locked at the electrical
receptacle;
Figure 16 is a sectional view through the heater
fan a.s it is being fitted to the bracket of Figure 3.
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DETA=:LED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Figure 1 shows a heater :Eon generally indicated at
1 supported on a building wall W above the floor F. The
wall 1 is fitted with a standard electrical outlet which
has a pair of plug receptacles. Such an outlet is shown in
Figure 3 of the drawings, located behind a mounting bracket
generally indicated at. 21 f.or supporting the heater fan and
suspending it from the wall-.
The heater fan itself comprises a casing 2 which is
preferably made from plastic. This casing encloses the
known fan and heater elements which are operated by manual
controls 3 and 5 on th.e front of the casing. Also provided
on the front of the casing is a grill 7 through which air
is b7_own from the heater fan. Again, as is known in the
art, this air can either be room temperature or heated air,
depending upon whether the heater part of the fan is being
operated.
Figure 2 shows that the rear of the heater fan is
provided with an electrical. cord 9, terminating with a plug
11. Electrical cord 9 is substantially shorter than a
conventional appliance cord and plug 11 is a relatively
low, flat profile plug providing advantages for reasons
which will be described later in detail.
Also provided to the rear of the casing is a recess
generally indicated at 15. This recess can be used as a
handle for picking up and holding the heater fan and is
additionally used as a receiving recess for the mounting
bracket for the heater fan. To this end, recess 15 is
provided with a downwardly depending hook portion 17 and a
lower sloped surface 19.
Mounting brackE=_t 21 as shown in Figure 3, which is
again. preferably made from a lightweight strong plastic,
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has ~~ main wall 23 provided with a cross-shaped opening 27.
This opening has a vertical part 27a and a horizontal part
27b.
In the set up shown in Figure 3 of the drawings,
the cover plate over the electrical outlet extends in the
vertical direction and. the two plug receptacles in the
cover. plate are exposed through the vertical portion 27a of
opening 27.
If the cover plate over the electrical outlet
extends in the horizontal position, then the two plug
receptacles will be exposed through the horizontal portion
27b of opening 27.
The main wall :23 of bracket 21 is bordered by a
raised edge 25. A pair of stops 29 are provided near the
bottom of the bracket. Bumpers 30 which are preferably
made from rubber, are provided o:n stops 29.
The upper end of the mounting bracket is provided
with an appliance hanger comprising an upwardly projecting
hook like portion 31 and a pair of webs 32, each of which
has a radiused undersurface 32a. Hook portion 31 and webs
32a f:it into the recess 15 on the back of the heater fan as
will be described later in detail.
Provided on the outer ends of the hook like portion
31 are a pair of again, preferably rubber sleeves 33, which
cooperate with bumpers 30 t.o act as dampeners between the
bracket and the heater fan to essentially eliminate
vibr~~tion noises during operation of the heater fan.
Bracket 21 is sized such that it is completely
covered by and hidden behind the heater fan. When the
heater fan and bracket are fully interlocked with one
anotr.er, they appear to be a single one piece unit. The
electrical cord of the heater fan, along with its plug, are
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hidden in the space between the bracket and the heater fan
which is created by the raised wall 25 which provides a
standoff between the main wall 23 of the bracket and the
back of the heater fan.. As earlier noted, the cord on the
heater fan is short, i.e., it only needs to be long enough
to f~_t through the bracket into the electrical outlet while
the heater fan is off the bracket and does not have to be
long enough to allow the heater fan to reach the floor.
Also the flat profiling of the plug allows it to easily fit
into the storage gap between the bracket and the heater
fan.
The bracket mount such a:~ bracket mount 35, shown
in Figure 3 of the drawings, is a very important feature of
the present invention. This bracket mount includes a main
plate portion 37 which carries a plug lock generally
indicated at 39. The plates 37 of the bracket mount
includes raised walls 38 to either side of the plug lock.
The malls provide grips for holding the bracket mount and
for ~>ushing it into and pulling .it from the wall
receptacle. They also act as stops for holding the plug
lock with the mounting bracket as will be described later
in detail.
The plug lock .itself is formed from an operating
component generally indicated at 61 in Figures 5 and 6 of
the drawings, and a housing generally indicated at 75 in
Figures 7 and 8 of the drawings. The operating component
61 fits within the housing 75, and housing 75 in turn, fits
:30 within the main body portion 37 of the bracket mount.
Operating component 61 is. formed from a cylindrical
body portion 63 having an elongated cylindrical post 65
depending from the bottom surface of body portion 63. As
:35 is well shown in Figure 5, post Ei5 is mounted off center of
body portion 63.
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A lever 69 is provided on the top surface of body
port_Lon 63 while a small rectangular tooth 67 extends from
the ride of the body portion, diametrically opposite lever
69.
As can be seen in Figure 6 of the drawings, a small
gap '~1 is provided between the bottom side of lever 69 and
the ride wall of body portion 63.
The housing 75 for receiving operating member 61
comprises a main circular body portion 77 provided with a
circular neck 80 with an opening 79 provided through the
neck. A small rectangular notch 81 is provided along the
side wall of neck 80.
Depending downwardly frorn the main body 77 of
housing 75 are a pair of flat prongs 85 and 87. Prong 85
is s7_ightly longer and. wider than prong 87 to fit with
corresponding prong openings in most up-to-date plug
receptacles .
As shown in Figure 8, opE~ning 79 is not centered
with respect to the two prongs, but rather is slightly
offset towards the smaller prong 87.
A side wall extension 83 is provided around the
main body of housing 75. This side wall extension presents
upper and lower shoulders 83a and 83b, respectively.
Operating member 61 and housing 75 are preferably
made from polyester with a 30~ g:Lass filler. This
combination of elements makes the plug lock flame retardant
and makes it extremely strong.
:35 The plates 37 of the bracket mount, again
preferably having a plastic const=ruction, includes a
central circular opening 51. This opening is defined by an
upper side wall 53 and a lower smaller diameter side wall
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55. A pair of flexible barbs 57 are located to either side
of opening 51.
In the first step of putting the bracket mount
together, operating member 61 is fitted into housing 75.
The tooth 67 of the operating member is aligned with notch
81 oi= the housing allowing the main cylindrical portion 63
carr5ring post 65 of the operating member to be sleeved into
the opening defined by circular wall 80 of the housing.
This wall provides a bearing for rotating the operating
member. The operating' member drops down sufficiently far,
such that tooth 70 completely clears through wall 80 which
rider up into the opening 71 between the lever 69 and the
cylindrical body portion 63 of the operating member. As
soon as the operating member is rotated such that tooth 67
of the operating member is out of alignment with notch 81
on the housing, the operating member and the housing are
rotat:ably coupled with. one another. The fitting of the
plug lock 39 which comprises operating member 61 and
housing 75 with the plate 37 of the bracket mount prevents
the operating member from rotating back to a position where
it can come out of its housing, thereby maintaining the
rotat:able interlock between the operating member and the
housing. This will be described later in further detail.
Once the operating membez- and housing have been
assembled as described above, they are pushed as a single
unit into the opening 51 in the plate 37 of the bracket
mount.. Figures 10 and 11 show that the orientation of the
plug lock can be varied relative to the orientation of the
plate of the bracket mount.
Regardless of t:he orientation, the housing 75 of
the ~~lug lock is cammed through the flexible barbs 57 to
either side of opening 51 with these barbs locking on the
upper' shoulders of the protruding side wall 83 on housing
75. The lower shoulders of protruding side wall 83 sits
against the inner wall 55 around opening 51 in the bracket
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mount. plate 37. The rousing of the plug lock is now
effectively trapped with the bracket mount.
Post 65 extends to one side of the bracket mount in
a truangular pattern with the two prongs 85 and 87 while
the operating lever 69 for the plug lock is located to the
other side of plate 37 and swingable within the raised
wall: 38 of plate 37. V~hen the plug lock is inserted in
plate 37, sidewalls 38 stop the lever from swinging and
cylindrical portion 63 from rotating far enough to allow
tooth 65 to line up with notch 80 and therefore prevent the
operating member from pulling out of the plate.
The swinging of the lever produces rotation of the
cylindrical body portion 63 of the plug lock and this in
turn produces an oscillating or orbiting motion of the post
relative to the circular housing portion 77 on the plug
lock. This orbiting motion occurs because of the off-
centering position of the post, relative to the cylindrical
body portion of the operating member.
As a result of the orbiting motion of the post on
the plug lock, it is adjustable between a plug receptacle
insertion position and a plug receptacle locked in
position. This is well demonstrated in comparing Figures
12 and 13 of the drawings.
More particularly, Figure 12 shows that the
cylinder 63 of the operating member is in a position such
that post 65 is aligned in a position centrally offset from
the t.wo prongs 85 and 87. Figure 13 shows that the
cylinder 63 has been rotated about 90° from position,
causing post 65 to orbit such that it is moved away from
the Figure 12 position to a position more directly beneath
and closer to prong 85.
The positioning of the two prongs and the posts in
Figure 12 is the same as the positioning as the prong slots
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and around opening in a standard plug receptacle which
allows the plug lock t.o be easily pushed in the Figure 12
position into the plug receptacle. Once the plug lock is
fitted into the receptacle) the operating member of the
plug lock is turned by its lever 69 which provides
substantial leverage t.o produce the orbiting of the post.
When the post is adjusted to the Figure 13 position, the
post wedges against the face plate over the receptacle as
the reparation between. the post and the prongs and in
part__cular, prong 85 is decreased with the orbiting of the
post.. This causes both the post and the prongs to clamp
onto the face plate.
The orbiting motion of the post to the clamped or
interlocked position is enhanced by the off center location
of tree bearing wall 80 for cylindrical portion 63 relative
to pz-ongs 85 and 87. This off center location enables the
post to more easily move within the ground opening to the
locking position.
The initial step in suspending the heater fan is to
first: mount bracket 21 at the electrical outlet, and more
particularly, with the face plate of the electrical outlet.
Here it should be noted from Figure 4 of the drawings that
bracket 21 on its front side, i.~s., the side that faces the
wall, has four corner members 34 and a wall 34a level with
these four corner members. The main wall 23 of the bracket
is recessed relative to corner members 34 and wall 34a.
Therefore, when the bracket is fatted over the face plate
on the wall, the face plate in f<~ct fits into the bracket
with the four corner members 34 of the bracket locking onto
the sides of the face :plate and the wall 34a of the bracket
locking onto the ends of the face plate. This happens
regardless of the direction of the face plate, i.e.,
whetY:.er the face plate is set in the vertical orientation
of Figure 3 or at 90° too the Figure 3 orientation where the
face plate sits horizontally.
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Once the bracket is properly positioned over the
face plate, the face plate itself stops the bracket from
twist=ing and the four corner members 34, as well as the
wall 34a of the bracket, fit flushly against the wall
supporting the face plate.
After the bracket has bean properly positioned as
described above, over the face plate, the plug lock is
adjusted or set to the plug receptacle insertion position,
is f:_tted into one of the plug receptacles leaving the
other receptacle exposed. The plug lock is then adjusted
to tree receptacle locked in position, to prevent separation
of tree bracket mount from the receptacle. The plate
portion 37 of the bracket mount overlaps the back surface
of tree wall 23 of the bracket trapping the bracket between
the building wall and the bracket mount.
It is the bracket mount which prevents the bracket
from releasing in a horizontal direction from the wall and
it ins the face plate secured to the outlet in the wall
which prevents the bracket from moving in a vertical
direction. This is well seen in Figure 15 of the drawings.
It is. therefore, the actual wall itself which supports the
load of the heater fan once it i;s hanging from the bracket.
Once the bracket has been mounted to the wall, it
is a very simple matter to plug the heater fan in at the
remaining exposed plug receptaclE=_ and to then hang the
heater fan from the bracket as shown in Figure 16 of the
:30 drawings. By tipping the heater fan, the hook 17 at the
upper side of receptacle 15 on the back of the heater fan
can h~e fitted over the hook 31 on bracket 21. The heater
fan is then simply allowed to drop down to its normal
upright positioning whereby the lower sloped wall 19 of the
:35 heater fan recess 15 locates beneath the radiused lower
surface 32a on the webs 32 of the bracket. There is a
slight gap between the web under surface 32a of the bracket
and the bottom wall 19 of the fan recess which allows the
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fan t:o effectively float on the rubber bumpers 33 of the
hook 31 of the bracket. hanger. This insulated hanging, as
well as the fitting of the rubber bumpers 30 on the bracket
against the back surface of the heater fan, provides an
extremely effective vibration dampener during operation of
the beater fan.
The description above re:Eers to the fact that the
face plate over the electrical outlet can be set in either
a vertical or horizontal orientation. When the face plate
is in the horizontal position and as earlier described, the
two plug receptacles will be located within opening portion
27b of the cross shaped opening in the bracket. The
bracl~:et mount will then be used in a position where the
main body portion of the bracket mount is turned 90° from
the Figure 3 position. Therefore, the bracket and bracket
mount. can accommodate both orientations of the face plate
without having to change the orientation of the bracket.
Figure 3a shows an arrangement in which the face
plate over a plug receptacle extends in a vertical
direction but the plug receptacles themselves are turned at
90° from the direction that they are set in Figure 3. This
orientation of the plug receptacles is easily accommodated
according to the present invention by simply installing the
plug lock into the main body portion 37 of the bracket
mount. in the Figure 11 position rather than the Figure 10
position. In comparing the two figures, it will seen that
in Figure 11, housing 75 carrying the operating member 61
is turned at 90° from t:he Figure 10 position. The
positioning of the prongs and the post on the plug lock
when the bracket mount is set up as shown in Figure 11, can
be seen in Figure 14 of the drawings. This produces a
bracket mount 35a which only differs from bracket mount 35
:35 with respect to the orientation of the plug lock. The
actual components used to make bracket mounts 35 and 35a
are identical.
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As will be understood from the above, the entire
assembly, regardless of the direction of the face plate
over the receptacle, a.nd regardless of the orientation of
the plug receptacles within the face plate, is set up
without requiring the need for any tools whatsoever. The
amount of support provided by the bracket is substantially
more than the holding force provided by a convention plug
on the back of a currently in use heater fan and is more
than sufficient to support the weight of a substantially
larger wall mounted heater fan than has been usable in the
past. Accordingly, this system is capable of supporting
the 7.oad of larger heating components to make the heater
fan capable of operating at up to 1500 watts of power.
A conventional electrical outlet is designed to
accept a maximum load of about 1500 watts. Therefore, the
plug lock of the bracket mount, in effect, provides a
safety feature because the plug :lock acts as a block at one
of the receptacles while the othar plug receptacle feeds
power to the heater fan.
Although the description above relates specifically
to a heater fan, it will be appreciated that the mounting
system can be used for various other different types of
small electrical appliances to be suspended from a wall.
The wall mounting system in the present invention thereby
eliminates the need for floor space and in the case of the
heater fan, raises the heater fan to the point where the
air flow is desirably up off of l.he floor in the building.
:30
Again, in accordance with the present invention,
the plug lock, using a combination of prongs with a cam
operated grounding post, can easily be adapted into a
standard electrical plug where the prongs are conductive
elements to produce a :live locking plug.
Although various preferred embodiments of the
present invention have been described herein in detail, it
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will be appreciated by those skilled in the art, that
variations may be made thereto without departing from the
spir__t of the invention or the scope of the appended
claims.
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