BACKGROUND OF THE INVENTION
[0001] The field of invention is protective security seals for electrical plugs plugged
into electrical sockets, and more particularly to security seals which protect electrical
plugs plugged into sockets and provide evidence of tampering with the plug.
[0002] Certain electrical devices, such as refrigerators in laboratories, medical devices,
computers, communication and manufacturing systems, must be continuously connected
to a source of electrical power to avert life threatening events, loss of sensitive
data or material, or prevent expensive restart. Electrical power to many of these
electrical devices is provided through an electrical plug plugged into an electrical
socket. The plug can be inadvertently pulled from the socket to disconnect the power,
or can be intentionally disconnected from the electrical source.
[0003] Even a temporary loss of electrical power can result in an undesirable event which
may not be detectable for a period of time. For example, loss of refrigeration for
a laboratory sample may alter the sample. The alteration of the sample could be the
result of a number of events. Therefore, without evidence of a potential loss of power
to the refrigeration equipment, the cause of the sample alteration could remain undetermined.
[0004] Security covers designed to protect children from electrical shock are known. However,
a plug protected by these devices is easily accessed by an adult without evidence
that security of the plug has been breached. Therefore, a need exists for a security
seal which provides evidence of tampering with the plug.
BRIEF SUMMARY OF THE INVENTION
[0005] The present invention provides a security seal for use with an electrical socket
to provide evidence of tampering with an electrical plug received in the socket. The
security seal includes a back plate having a rearwardly facing rear surface fixable
relative to the electrical socket and a forwardly facing front surface. The back plate
has at least one opening which extends between the front and rear surfaces which is
alignable with pin receptacles of the socket. A cover is detachably mounted to the
back plate, and defines a cavity for covering an electrical plug having pins extending
through the back plate openings and received in the socket pin receptacles. Detaching
the cover from the back plate to gain access to the plug deforms the cover to provide
evidence of tampering with the electrical plug. Preferably, the cover is deformed
by tearing.
[0006] A general objective of the present invention is to provide a security seal which
provides evidence of tampering. This objective is accomplished by a seal which permanently
deforms when a user gains access to the protected plug.
[0007] Another objective of the present invention is to provide a security seal which inhibits
access to a plug plugged into an electrical socket. This objective is accomplished
by providing a security seal having a cover which encloses the plug plugged into the
socket.
[0008] The foregoing and other objects and advantages of the invention will appear from
the following description. In the description, reference is made to the accompanying
drawings which form a part hereof, and in which there is shown by way of illustration
a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009]
Fig. 1 is a perspective view of a security seal incorporating the present invention;
Fig. 2 is an exploded perspective view of the security seal of Fig. 1;
Fig. 3 is a bottom perspective view of the security seal of Fig. 1;
Fig. 4 is a perspective cut away view of the security seal of Fig. 1;
Fig. 5 is a cross sectional view of the security seal of Fig. 1;
Fig. 5A is a detailed cutaway view of the security seal of Fig. 1;
Fig. 6 is a perspective view of another security seal incorporating the present invention;
and
Fig. 7 is an exploded perspective view of the security seal of Fig. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] Referring to Figs. 1-5, a security seal 10 includes a molded back plate 12 which
is fixed over an electrical socket 14, and a molded cover 16 which is detachably mounted
to the back plate 12. The cover 16 encloses a plug 18 having electrical conductor
pins 20 inserted into electrical socket pin receptacles 30. The cover 16 prevents
easy access to the plug 18, and reduces the risk of inadvertently disconnecting an
electrical device from a source of electrical energy by pulling the plug 18 from the
socket 14. Detaching the cover 16 from the back plate 12 to gain access to the plug
18 permanently deforms the cover 16 or back plate 12, such as by tearing or breaking
the cover 16 or breaking the back plate 12 to provide evidence of tampering.
[0011] The back plate 12 is a substantially flat plate having a rearwardly facing rear surface
24 which abuts the socket 14 and a forwardly facing front surface 26 which is enclosed
by the cover 16. Apertures 28 formed in the back plate 12 are aligned with socket
pin receptacles 30 for insertion of the plug conductor pins 20 into the electrical
socket pin receptacles 30. Although a separate aperture aligned with each pin receptacle
30 is disclosed, a single aperture which allows insertion of the plug conductor pins
20 into the socket pin receptacles 30 can be provided without departing from the scope
of the present invention.
[0012] An adhesive applied to the back plate rear surface 24 adhesively attaches the back
plate 12 to the socket 14. Of course, other methods for fixing the back plate 12 to
the socket 14 can be used, such as screws, and the like, without departing from the
scope of the present invention.
[0013] Feet 32 extending substantially perpendicular from the back plate 12 below the holes
34 support the cover 16 mounted to the back plate 12. Holes 34 formed in the feet
32 engage downwardly projecting posts 36 formed in the cover 16 to prevent slidable
movement of the cover 16 relative to the feet 32, and positions the cover 16 over
the plug 18 plugged into the socket 14. Locating structure 38 and holes 40 can be
formed in the back plate front surface 26 to engage the cover 16 and properly position
the cover 16 relative to the back plate 12.
[0014] Referring to Figs 2-5, a resilient shelf 42 extending substantially perpendicular
from the back plate front surface 26 above the apertures 28 includes a downwardly
opening catch 44. The catch 44 engages an upwardly projecting latch 43 formed in the
cover 16 to lock the cover 16 to the back plate 12 over the plug 18. Of course, the
catch 44 can be formed as an integral part of the cover 16 and the latch 43 as an
integral part of the back plate 12 without departing from the scope of the present
invention.
[0015] The cover 16 defines a rearwardly opening primary cavity 45 which encloses the plug
18 having electrical conductor pins 20 inserted through the back plate apertures 28
into the socket pin receptacles 30. The primary cavity 45 is defined by a bottom wall
46, top wall 48, and side walls 50 joined by a front wall 52 to enclose the plug 18
plugged into the socket 14. An opening 54 formed in the cover bottom wall 46 provides
a passage for a cord connected to the plug 18. A depression 56 formed in the front
wall 52 provides a location for labeling the cover 16, such as to designate the electrical
device electrically connected to the plug 18 plugged into the socket 14.
[0016] The cover 16 is vertically supported by the feet 32 which engage the cover bottom
wall 46. The downwardly projecting posts 36 extending from the cover bottom wall 46
are received in the feet holes 34. Although pins engaging holes in feet are disclosed
herein for positioning and supporting the cover, other methods, such as disclosed
in the alternative embodiment shown in Figs. 6 and 7, can be used without departing
from the scope of the present invention.
[0017] Switch protectors 58 formed as an integral part of the side walls 50 define rearwardly
facing secondary cavities adjacent the primary cavity 45 to cover an electrical control
device 60, such as a switch, button, and the like, adjacent the socket pin receptacles
30. The switch protectors 58 cover the electrical control device 60 to prevent access
to, and thus, operation of the control device 60.
[0018] The upwardly projecting latch 43 formed in the cover top wall 48 engages the catch
44 formed in the base plate shelf 42. The latch 43 is straddled by a pair of legs
62 supporting a pull tab 64 having a pull ring 66 formed on its distal end. The legs
62 define an opening in the pull tab 64 which receives the shelf 42 when the cover
16 is mounted on the back plate 12. Preferably, when the cover 16 is engaged with
the back plate 12, the tab 64 abuts the back plate 12 to prevent rearwardly movement
of the tab 64 and disengagement of the latch 43 from the catch 44 by pivoting the
tab 64 rearwardly.
[0019] The cover top wall 48 and shelf 42 are resilient members which allow engagement of
the latch 43 with the catch 44 without permanently deforming, such as tearing or breaking,
the cover 16 or shelf 42. Disengaging the latch 43 from the catch 44, by grasping
the pull ring 66 and pulling the tab 64 forwardly away from the back plate 12, tears
the cover top wall 48 and pulls the latch 43 from the catch 44. Tearing the cover
top wall 48 permanently deforms the cover 16 to provide evidence of tampering with
the cover 16, and thus the plug 18. In the embodiment shown herein, the cover top
wall 48 is scored around the tab 64 to facilitate tearing of the cover top wall 48
when disengaging the latch 43 from the catch 44.
[0020] Preferably, as shown in Fig. 5A, the latch 43 is supported at each end by break away
supports 47 which break when the cover 16 is detached from the back plate 12 to deform
the cover 16 and prevent reattachment of the cover 16 to the back plate 12. The supports
47 support the latch 43 above the cover top wall 48 and define a gap 49 between the
cover top wall 48 and latch 43. The latch 43 supported by the supports 47 can be provided
in addition to, or independent of the scoring without departing from the scope of
the present invention.
[0021] In use, the back plate 12 is adhesively fixed to the socket 14, such that the back
plate apertures 28 are aligned with the socket pin receptacles 30. The plug 18 having
a downwardly extending cord is plugged into the socket 14 by inserting the plug conductor
pins 20 through the back plate apertures 28 and into the socket pin receptacles 30.
The cover 16 is positioned over the plug 18 and the downwardly projecting locating
posts 36 are slipped into the alignment holes 34 formed in the feet 32. The cover
latch 43 is then snapped into engagement with the back plate catch 44 by pivoting
the cover 16 rearwardly until the latch 43 engages the catch 44.
[0022] To gain access to the plug 18, a user grasps the pull ring 66 and tears the cover
top wall 48 away from the back plate 12 and side walls 50 to disengage the latch 43
from the catch 44. Once the latch 43 is disengaged from the catch 44, the feet locating
posts 36 are slipped out of the alignment holes 34 in the feet 32 to expose the plug
18. Once the cover top wall 48 has been torn away, it cannot be reused and provides
evidence that plug security has been breached. The adhesively mounted back plate 12
can be removed by prying the back plate 12 away from the socket 14.
[0023] In an alternative embodiment shown in Figs. 6 and 7, a security seal 100 includes
a molded back plate 102 which is fixed over an electrical socket 104, and a molded
cover 106 is detachably mounted to the back plate 102. As in the first embodiment,
the cover 106 encloses a plug 108 having conductor pins 109 plugged into the socket
104 through apertures 110 formed in the back plate 102 and aligned with socket pin
receptacles 112.
[0024] Locating structure 117 formed in the back plate front surface 116 engage the cover
106 and properly position the cover 106 relative to the back plate 102 over the plug
108. The locating structure 117 includes ridges 118 which extend forwardly from the
back plate front surface 116 to engage an inner surface of the cover 106, and locating
pins 120 which extend forwardly from the back plate front surface 116 and are received
in rearwardly facing locating cavities formed in the cover 106.
[0025] A switch protector 122 is formed as an integral part of the back plate 102, and defines
a rearwardly facing cavity to cover an electrical control device, such as a switch,
button, and the like, adjacent the socket 104. The switch protector 122 covers the
electrical control device adjacent the socket pin receptacles 112 when the back plate
102 is fixed relative to the socket 104 to prevent access to, and thus, operation
of the control device.
[0026] The cover 106 includes a bottom wall 124, top wall 126, and side walls 128 joined
by a front wall 131 which defines a rearwardly opening primary cavity which encloses
the plug 108. The cover 106 is supported adjacent to the back plate 102 by the locating
structure 117 extending from the back plate 102.
[0027] As in the first embodiment, an upwardly projecting latch 133 formed in the cover
top wall 126 engages a downwardly opening catch formed in a shelf 130 extending from
the back plate 102. A pull tab 132 is formed as an integral part of the cover top
wall 126, and has a pull ring 134 formed on its distal end.
[0028] The cover top wall 126 and shelf 130 are resilient members which allow engagement
of the latch 133 with the catch without permanently deforming the cover 106 or shelf
130. Disengaging the latch 133 from the catch, by grasping the pull ring 134 and pulling
the tab 132 forwardly away from the back plate 102, tears the cover top wall 126 and
pulls the latch 133 from the catch. Tearing the cover top wall 126, permanently deforms
the cover 106 to provide evidence of tampering with the cover 106, and thus the plug
108.
[0029] In use, as in the first embodiment, the back plate 102 is fixed to the socket 104,
such that the back plate apertures 110 are aligned with the socket pin receptacles
112. The plug 108 having a downwardly extending cord is plugged into the socket 104
by inserting the plug conductor pins 109 through the back plate apertures 110 and
into the socket pin receptacles 112. The locating structure 117 positions the cover
106 over the back plate 102 and plug 108, and the latch 133 is snapped into engagement
with the catch by urging the cover 106 against the back plate 102 to lock the cover
106 over the plug 108.
[0030] To gain access to the plug 108, a user grasps the pull ring 134 and tears the cover
top wall 126 away from the side wall 128 to disengage the latch 133 from the catch.
Once the latch 133 is disengaged from the catch, the cover 106 is pulled away from
the back plate 102.
[0031] While there has been shown and described what are at present considered the preferred
embodiment of the invention, it will be obvious to those skilled in the art that various
changes and modifications can be made therein without departing from the scope of
the invention defined by the appended claims. For example, structure, such as switch
protectors, for protecting an electrical control device adjacent the socket pin receptacles
can be omitted without departing from the scope of the present invention. Therefore,
various alternatives and embodiments are contemplated as being within the scope of
the following claims particularly pointing out and distinctly claiming the subject
matter regarded as the invention.
1. A security seal for use with an electrical socket to provide evidence of tampering
with an electrical plug received in the socket, said security seal comprising:
a back plate having a rearwardly facing rear surface fixable relative to the electrical
socket and a forwardly facing front surface, and having at least one opening extending
between said front and rear surfaces and being alignable with pin receptacles of the
socket; and
a cover detachably mounted to said back plate, and defining a cavity for covering
an electrical plug having pins extending through said back plate openings and received
in the socket pin receptacles, wherein detaching said cover from said back plate permanently
deforms at least one of said cover and said back plate to provide evidence of tampering
with the electrical plug.
2. The security seal of claim 1, in which said cover is detachably mounted to said back
plate with a latch fixed to one of said back plate and said cover, and
a catch fixed to the other of said back plate and said cover, and engageable with
said latch, wherein disengagement of said latch from said catch deforms said cover
to provide evidence of tampering with the electrical plug.
3. The security seal of claim 2, in which a pull tab is formed as an integral part of
said cover, pulling said tab tears said cover to disengage said catch from said latch
and renders said cover unusable with said back plate.
4. The security seal of claim 2, in which said latch is supported at each end by break
away supports which break when said cover is detached from said back plate.
5. The security seal of claim 4, in which a ring is formed on a distal end of said pull
tab for grasping by a user.
6. The security seal of claim 1, in which said back plate includes a rearwardly opening
cavity formed in said back surface for covering an electrical control device adjacent
to the pin receptacles.
7. The security seal of claim 1, in which locating pins extend forwardly from said back
plate for engagement with said cover to position said cover relative to said back
plate.
8. The security seal of claim 1, in which feet extend forwardly from said back plate,
and said feet vertically support said cover detachably mounted to said back plate.
9. The security seal of claim 8, including locating holes formed in said feet for engagement
with locating pins extending from said cover.
10. The security seal of claim 1, in which said back plate has locating holes formed therein
for receiving locating posts extending from said cover to position said cover relative
to said back plate.
11. The security seal of claim 1, in which said cover includes another cavity which covers
an electrical control device adjacent to the pin receptacles.
12. The security seal of claim 1, in which adhesive is applied to said back plate back
surface to fix said back plate relative to the socket.
13. The security plug of claim 1, in which a depression is formed in said cover for affixing
a label.