Lock for preventing unauthorized use of electrical appliances

A small box with a keyed lock into which an electrical plug is placed and then locked for preventing the insertion of the electrical appliance plug into a wall socket comprises a plastic box (A) with a front sliding door (B) and a keyed cam lock (D).

BACKGROUND-FIELD OF INVENTION 
This invention relates to locks, specifically locks designed to be used 
with any electrical product that has an electrical chord and plug to be 
inserted into an electrical outlet. 
BACKGROUND-DISCUSSION OF PRIOR ART 
Many Americans at one time or another have struggled with the problem of 
preventing unwanted or unauthorized usage of electrical appliances like 
televisions, vcr's, stereo's and computers, especially by small children 
in the case of the television and home appliances like blenders, power 
saws and electric knives. 
Heretofore prevention required building expensive cabinets with locks, 
lugging the electrical appliance out to the garage or into a closet with a 
lock. 
Most owners of such appliances find these options cumbersome, laborious and 
often expensive. 
Many people would find it desirable to have a lock that was small, 
inexpensive and simple to prevent usage of electrical appliances without 
the hassle of having to move the appliance or house it in an expensive 
cabinet. 
OBJECTS AND ADVANTAGES 
Accordingly we claim the following as our objects and advantages of the 
invention: to provide a lock that easily, reliably, durably and cheaply 
allows the blocking of an electrical device like a television from being 
plugged into a wall socket. 
In addition we claim the following additional objects and advantages: to 
provide a simple alternative to physically relocating an electrical 
appliance to prevent its usage, security from unwanted tampering with 
computer files when not present, safety from accidental harm from 
unsupervised usage of dangerous household items like power tools and 
blenders and to provide an additional impediment to usage through theft. 
Readers will find further objects and advantages of the invention from 
consideration of the ensuing description and the accompanying drawings. 
SUMMARY 
This invention is a lock box for receiving and locking onto the terminal 
plug of the power cord of an appliance, ordinarily a television set or 
computer, for the purpose of limiting the exposure time of children to 
television and mind-numbing video games. Its use is also contemplated on 
power tools, hot plates, lawnmowers and other electrical devices having a 
high propensity to injure children who may be playing in the absence of 
parental supervision. 
The body of the box comprises a five-sided, box-like enclosure molded as a 
single piece of durable plastic. The plastic enclosure encloses an 
interior space which is accessible through a rectangular entryway opening 
which would have been the sixth side of the box-like enclosure. The 
opening is closed by a sliding door which tracks in internal tracking 
grooves in the sidewalls of the enclosure and passing through a clearance 
slot in the top wall. 
The door is dimensioned to seat in the tracking grooves with the door edges 
substantially completely overlapped by the grooves. The trailing edge, 
which terminates in alignment with the exterior surface of the enclosure, 
likewise provides no cracks so that substantially no cracks exist around 
the door for prying the door in the opening direction with a knife edge. 
An edge aperture defined in the leading edge of the door is just large 
enough to provide clearance for an electrical apparatus power cord, but 
not large enough to pass the plug, and an externally accessible cam lock 
mounted in the enclosure has means to engage the door from the inside and 
lock it. A nib or nibs provided on the door prevent it from accidentally 
escaping completely through said slot and becoming lost, so that the 
entire assembly is integral and self-contained except for a separate key 
in the event a key-operated lock is used.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
As shown in FIG. 1, the lock box A of the instant invention is square in 
cross section, being 2 inches tall, 31/2 inches long and 21/4 inches wide 
in the preferred embodiment. A groove F defined continuously around the 
interior of the box provides a track for the sliding door B to slide in 
and seat. Once closed, the door is locked by cam lock D, on the side of 
the box as best shown in FIG. 4. The lock has a tongue which swings onto 
the slot C defined in a projection from the rear of the door B. The door 
has an opening E entrant from the lower edge to pass the cord of an 
appliance therethrough so that the plug is inside the box as shown in FIG. 
5. 
The body of the box A and the door B are preferably made of high quality, 
durable plastic such as ABS plastic made by DuPont Chemical Company. Any 
available durable material can be used for the box and the door. 
Although theoretically the box may be any size, it is preferably small and 
light-weight for convenience, yet defining enough interior space to house 
any common electrical two- or three-pronged plug. Wall thickness may vary, 
and it is desirable that all edges are radiused to reduce the risk of 
injury from the sharp comers and improve the esthetic appearance of the 
invention. 
Many other variations will occur to those skilled in the art based on the 
forgoing description of the Preferred Embodiment, which is illustrative 
and not limiting. 
OPERATION 
The plastic box (A) shown in FIG. 1 will effectively enclose and lock 
around the plug to any standard electrical appliance when the plug to said 
appliance is placed inside said box and sliding door (B) shown in FIG. 3 
is inserted into place and the keyed cam lock (D) shown in FIG. 4 is moved 
to the lock position by turning the key in a counter-clockwise direction 
lowering the lock cam into the slot protruding from the door, preventing 
the removal of said plug from said box and preventing the insertion of 
said plug into a wall socket thereby preventing the use of said appliance. 
CONCLUSION, RAMIFICATIONS AND SCOPE OF INVENTION 
Thus the reader will see that the lock box provides a cheap, effective, 
highly reliable, durable, economical, light weight and efficient device 
that can be used on any electrical appliance with a plug. 
While my above description is geared mainly towards the usage of this 
device by parents to effectively control the amount of television their 
children watch this should not be construed as limitations on the scope of 
the invention, but rather as an exemplification of one preferred 
embodiment thereof. Many other variations are possible. For example the 
invention can also prohibit the unwanted access of computer files or 
utilization of stereos, vcr's and other entertainment equipment and also 
serve as a safety device to prevent small children from harming themselves 
with many of the dangerous products in the average household such as power 
tools and blenders. Accordingly, the scope of the invention should be 
determined not by the embodiment(s) illustrated, but by the appended 
claims and their legal equivalents.