FIELD OF INVENTION
The present invention relates to a electronic energy meter and.in particular to
the electronic energy meter, for household, structured with a secured enclosure for
which can measure electric energy and thus consumption with a high accuracy.
BACKGROUND OF THE INVENTION
The statements in this section merely provide background information related
to the present disclosure and may not constitute prior art(s).
An energy meter (also known as watt hour meter) is a device that measures
the amount of electrical energy supplied to or produced by a residence, business or
machines. The energy meter registers this amount of energy by the unit of kilowatt
hour which is equivalent to the amount of energy used by a load of one kilowatt in
one hour. The energy meter is structured with two or three parts wherein the parts are
joined/faGened together to result in a consolidated energy meter. These parts are
.. generally sealed by plastic seals in a way that the internal mgement is not
accessible to the unauthorized persons. However, these energy meters could be easily
tempered by opening the top cover from the base. Another tampering method is by
way of introducing spar discharge device capable of generating high voltage. sparks
through junction of top cover and a base. Similarly, other tampering methods include
chemical injection, breaking the energy meter via terminal cover, burning the meter
and many more. Thus, the currently available sealing arrangement can be easily
duplicated and thus is prone to being easily tampered.
, In order to overcome the tampering of the energy meters, ultrasonic welding
(of plastic) is now a days used. ,However, the ultrasonic welding is the most
complicated process. Additionally, any variation during the ultrasonic welding may
results into breakage of the structure also. Additionally, the process of ultrasonic
welding generates heat and vibration along the circumference of the energy meter
which may result in the subsequent damage of PCBIelectronic components. .In other
words, the energy meters should have an additional option of sealing the parts of the
energy meter in order to save the energy meters from tampering.
Hence, there is an urgent need for an urgent need of a secured and easily
structured arrangement for energy meters that may overcome the above mentioned
drawbacks with a view to introduce and develop a secured energy meter that may
drastically reduce the tampering of the energy meters and fbrther tampering of these
energy meter may results in breaking of energy meters irreparably.
BRlEF SUMMARY AND 0B.TECTTVES OF THE INVENTION
The present subject matter relates to a tamper-proof electronic energy meter
for measuring and displaying electrical energy carried on power lines. The electronic
energy meter includes an energy meter base comprising two side walls, a top wall
along with a rear wall resulting into a three sided envelop with fiont side and bottom
side open. The electronic energy meter is also provided with a printed circuit board
assembly fixed within the energy meter base, a nameplate mounted on the printed
circuit board assembly, and a cylindrical meter cover shaped to encompass the
printed circuit board assembly and the nameplate, wherein the cylindrical meter cover
is ultrasonically welded to the energy meter base thereby closing the fiont side of the
energy meter base. The electronic energy meter, in accordance with the present
subject matter, is provided with a terminal cover assembly secured fiom the bottom
of the energy meter cover wherein the terminal cover assembly comprises of a
terminal cover movable in a cam and follower mechanism.
An object of the present subject matter is to structure the electronic energy
meter with an integrated cover assembly and a terminal cover assembly.
An object of the present subject matter is to combine a top cover assembly
with an energy meter base to result in the integrated cover assembly.
An object of the present subject matter is to include a terminal cover,
terminals and the terminal block in the terminal cover assembly.
'An object of the present subject matter is to successively mount the
cylindrical meter cover, the nameplate, and the printed circuit board assembly to the
energy meter base.
Ah object of the present subject matter is to hold the PCB assembly by PCB
holders.
An object of the present subject matter is to secure the cylindrical meter cover
to the energy meter base by various means such as ultrasonic welding, a push seal and
a latch mechanism.
An object of the present subject matter is structure the push seal. with a latch
mechanism and a stopper.
I An object of the present subject matter is to frame the printed circuit board I
I assembly with 'electricaVelectronic components such as atleast one power current I
transformer, atleast one current transformer, a printed circuit board assembly, primary
wires, shunt, and the like.
An object of the present subject matter is to indicate the meter rating, brand
name, logo and other information of the manufacturer on the nameplate.
Another object of the present subject matter is to'provide the nameplate. with
with a hole for installing a spring loaded push button electrically connected to the
printed circuit board assembly.
Another object of the present subject matter is to additionally provide the
nameplate with an elliptical hole through which an inh-red communication device
protrudes that convey the instant and archived meter reading of the 'electronic energy
meter.
Another object of the present subject matter is to provide the electronic energy
meter with a cylindrical meter cover placed ova the nameplate attaching the
cylindrical meter cover to the energy meter base.
Another object of the present subject matter is to attach the cylindrical meter
cover to the energy meter base by fastening means such as fasteners, screws, and the
like.
Yet another object of the present subject matter is to convey the reading of the
electronic energy meter by various communication protocols such as infia-red rays,
radio-frequency waves, global positioning radio services, and the like.
Yet another object of the present subject matter is to provide access ofthe
terminal blocks to .the authorized users for making electrical connections to the PCB
assembly.
Another object of the present subject matter is to seal the terminal cover to the
terminal block by a sealing screw.
Yet another objective of the present invention is to provide an electronic
. means that leave a visible warning of 'COVER OPEN' or 'CO' on the liquid crystal
display of the electronic energy meter in base of any tampering of the electronic
energy meters.
Yet another objective of the present invention is to provide an easy, compact,
less costly and a truly production friendly electronic. energy meter along with the
advantages of secureness, reliability, customer's satisfaction, and the like.
BRIEF DESCRIPTION OF DRAWINGS
The summary narrated above and the following detailed description of the
invention can be understood with the drawings appended to this claim. The
illustrations provide the details of the invention. However, it should be understood
that the invention is not limited to the arrangements shown. In the drawings:
FIG. 1 shows a perspective view of an electronic energy meter in an embodiment of
the present subject matter.
FIG. 2 illustrates an exploded view of an electronic energy meter in an embodiment
of the present subject matter.
FIG. 3 illusktes a front perspective view of the energy meter base in w embodiment
of the present subject matter.
FIG. 4 illustrates a perspective view of a latch mechanism and a stopper in an
embodiment of the present subject matter.
FIG. 5 illustrates a perspective view of a closed terminal cover provided with an
electronic energy meter in an embodiment of the present subject matter.
FIG. 6 illustrates a perspective view of an open terminal cover provided with an
electronic energy meter in an embodiment of the present subject matter.
DETAILED DESCRIPTION OF THE INVENTION
The embodiments of the prcscnt subject matter are described in detail with
reference to the accompanying drawings. However, the present subject matter is not
limited to these embodiments which are only provided to explain more clearly the
present subject matter to the ordinarily skilled in the art of the present disclosure. In
the accompanying drawings, like reference alphabets and numerals are used to
indicate like components. The drawings are not necessarily drawn to the scale, and in
some instances the drawings have been exaggerated and/or simplified inplaces for
illustrative purposes only.
The present invention relates to an electronic energy meter and in particular to
the electronic energy meter, for household purpose, structured with a secured
enclosure for housing electronic energy meter which can measure electric energy and
thus consumption with a high accuracy. Electronic energy meters, also referred to as
"watt-hour meters," are used on a widespread basis in residential, commercial, and
industrial applications to measure the amounts of utility, such as electricity, gas, and
the like, that are being utilized by customers. These electronic energy meters are
typically mounted on an exterior or interior wall of a building being monitored. The
following description is merely exemplary in nature and is not intended to limit the
present disclosure, application, or uses. The present invention will hereinafter be
described in detail below as applied to an electronic energy meter for household
purposes. However, the principles of the present invention are also applicable to other
meters applicable to measure a particular unit in any other application(s).
FIG. 1 illustrates a perspective view of an integrated electronic energy meter
100 in accordance with an embodiment of the present subject matter. The electronic
energy meter 100 is structured mainly with an integrated cover assembly and a
terminal cover assembly 102. The integrated cover assembly is formed of a top cover
assembly and an energy meter base 104,'in an embodiment of the present subject
matter. The energy meter base 104 encompasses all the electronic components such
as, but not restricted to, atleast one power current transformer, atleast one current
transformer, a printed circuit board assembly, primary wires, shunt, and the like, as
discussed later. In an embodiment of the present subject matter, the terminal cover
assembly 102 includes a terminal cover, a terminal block and a terminal. The service
cables are secured to the terminal block by grub screws in another embodiment of the
present subject matter. In a unique embodiment of the present subject matter, the
terminal cover is sealed to the terminal blocks by a sealing screw, as discussed later.
FIG. 1 also shows an Infia-red cover 106 provided on the fiont face of the top cover
assembly as an opening to note and analyze the information conveyed by the
electronic energy meter 100. In a unique embodiment of the present subject matter,
the terminal cover is provided with integral follower (in a cam-follower mechanism)
designed to rotates along the movement 'of the terminal cover.
FIG. 2 illustrates an exploded view of the electronic energy meter 100 in
accordance with an embodiment of the present subject matter. With respect to FIG. 2,
the electronic energy meter 100 comprises of the energy meter base 104 which is
provided with two side.walls 106 and a top wall 108 along with a rear wall 110
resulting into a three sided envelop with front side open and bottom side left for the
terminal cover assembly, in an embodiment of the present subject matter. FIG. 3
shows a fiont perspective view of the energy meter base' 104 wherein the energy
meter base 104 is integrally molded with various mountings on the interior of its both
side walls 108, in an embodiment of the present subject matter. These mountings
preferably includes atleast one nameplate mounting 114, atleast one PCB (printed
circuit board) mounting 116, atleast one PCB holder 118, and the like. The energy
meter base 104 is M e r designed with molded arrangements for sealing screws 120
and push seal 122 in a unique embodiment of the present subject matter. In a unique
embodiment of the present subject matter, the push seal is structured with a latch
mechanism 140 and a stopper 150, as shown in FIG. 4. The latch mechanism 140 is
distinguishly designed to avoid any tampering (by any unauthorized access) in a
direction vertical to the energy meter. FIG. 4 shows an exemplary embodiment of the
present subject matter, the push seal 122 is also provided with atleast two stoppers
150 to avoid the tampering in the horizontal direction as well. FIG. 3 also illustrates
at least two tapered surfaces 124 protruded on the bottom wall of the energy meter
base 104. These tapered surfaces 124 are provided to place the power current
transformer 126 and the current transformer 128 respectively.
As mentioned in the previous paragraphs, the electronic energy meter 100 is
provided with the printed circuit board assembly 130 including electricaVelectronic
components such as but not restricted to the power current transformer 126, the
current transformer 128, primary wires, shunt, capacitor, resistor, tact switches, and
the like mounted on a printed circuit board 132 (hereinafter may be referred as PCB).
In an embodiment of the present subject matter, the printed circuit board assembly
130 is screwed (by screw, bolts, bosses, faster, etc) to the bottom plate of the energy
meter base 104 of the electronic energy meter 100. The printed circuit board
assembly 130 may be attached to the bottom plate of the energy meter base '104 by
any other means such as snap-fit mechanism, latch mechanism and the like in an
embodiment of the present subject matter. In another embodiment of the present
subject matter, the printed circuit board assembly 130 is held by atleast two PCB
holders 118, as shown in FIG. 3. The printed circuit board assembly 130 is mounted
in a way that the current transformer 128 and the power current transformer 126,
mounted on the printed circuit board 132, get aptly set in the tapered surfaces 124
protruded on the bottom wall of the energy meter base 104. The printed circuit board
132 is also provided with a liquid crystal display 134 for displaying the rating and the
power consumption of the household.
In an embodiment of the present subject matter, the nameplate 136 is mounted
on the printed circuit board assembly 130, thus covering the printed circuit board
assembly 130. The nameplate 136 is preferably used for indicating the meter rating,
brand name, logo and other information of the manufacturer, and the like, in a unique
embodiment of the present subject matter. The nameplate 136 is provided with a
rectangular groove so that one can access the reading of the power. consumption on
the liquid crystal display 134 through that rectangular groove. The nameplate 136 is
fiuther designed with a hole for installing a spring loaded push button (not shown)
which is electrically connected to the printed circuit board assembly 130. The
nameplate 136 is additionally provided with an elliptical hole through which an i&-
red communication device 138 protrudes that is generally used to quickly read the
instant and archived meter reading of the electronic energy meter 100, in an
embodiment of the present subject matter. The nameplate 136 is made of aluminum
in an embodiment of the present subject matter.
In another embodiment of the present subject matter, the electronic energy
meter 100 is provided with a cylindrical meter cover 140 that is placed over' the
nameplate 136 attaching the cylindrical meter cover 140 to the energy meter base 100.
.The cylindrical meter cover 140 is attached to the energy meter base 100 via
fastening means such as screws, fasteners, and the like which are well received in the
molded arrangements structured integrally to the exterior of the energy meter base.
Additionally, the cylindrical meter cover 140 is latched to the energy meter base 104
through a latch mechanism which is fkther strength-held by atleast' two push seals
122 fiom both sides 108 as shown in FIG. 4 in an embodiment of the present subject
matter. In an exemplary embodiment of the present subject matter, the energy meter
base 104 is ultrasonically welded to the cylindrical meter cover 140 so that the two
parts get sealed to result in an integrated part. In another embodiment of the present
subject matter, the cylindrical meter cover 140 is uniquely provided with an aperture
in a variety of locations to allow for ease of meter rating by any external electronic or
other energy management devices 138. In an embodiment of the present subject
matter, the. reading of the meter is communicated by various communication
protocols such as but not restricted to infia-red rays, radio-frequency waves, global
positioning radio service, programmable logic control, and the like. Therefore, the
aperture is smartly covered by an infia-red plate and subsequently by an infia-red
cover to protect the infka-red communication device 138 accessible through the said
aperture, as shown in FIG. 2.
FIG. 5 illustrates a perspective view of the terminal cover assembly 102 of
the electronic energy meter 100 in accordance with an embodiment of the present
subject matter. The terminal cover assembly 102 comprises of the terminals 142
embedded in the terminal block 144 that is accessible to the authorized user (such as
electricians) for making electrical connections (wires) of the PCB assembly 130, in
an embodiment of the present subject matter. The terminal block 144 is covered by
the terminal cover 146 which is screwed to the terminal block 144 by a sealing screw
once all the electrical connections are covered. In a unique embodiment of the present subject matter, the terminal cover 144 is provided with .unique follower 148 (in the
carn-follower mechanism) that holds the terminal cover 144 movable in an arc as
shown in FIG. 6.
The electronic energy meter 100 according to the present subject matter
advantageously facilitates simpler and secured arrangement for the construction of
the electronic energy meter. This electronic energy meter 100 provides an additional
alternative of sealing the parts of the electronic energy meter by push seals, latch
mechanism, and the like apart' from' ultrasonic welding. Thus, such multiple options
of integrating various parts of the electronic energy meter strengthens the solidity of
the electronic energy meter and thus provides high degree of protection against
tampering by any unauthorized user. Additionally, the integration of energy meter
base 104 and the cylindrical meter cover 140 by ultrasonic welding in the electronic
energy meter 100 leaves no gap in between those parts which subsequently reduces
any remote chances of ingress of dust and water into the electronic energy meter.
Further, since the energy meter base is open from two sides, hence the positioning of
10 '
various other parts such as PCB assembly, nameplate, cylindrical meter cover, etc
becomes easy compared. to the concepts present in the prior arts. Moreover, the
presence of movable followers provided on .the terminal cover diminishes the
redundant requirement of hinge or detents. Hence, the process of manufacturing these
electronic energy meter also gets simpler that consequently reduces the overall cost
involved in manufacturing too. Therefore, the electronic energy meter manufactured
according to the present subject matter, is a tamper-proof construction wherein the
accessing or disturbing the internal components is very difficult. It is because, the
I presence of push seal, latch mechanism and the ultrasonic welding makes the
electronic energy meter to be used only once. Also, the electronic energy meter is
provided with an electronic means that leave a visible warning of 'COVER OPEN' or
'CO' on the liquid crystal display of the electronic energy meter in an embodiment of
I the present subject matter. In addition to this, visible evidences ofLopening or
tampering the electronic energy meter are also evident if any attempt of breaking the
side lock, terminal cover, etc is made. Thus, the electronic energy meter 100 in
accordance with the present subject matter is a truly production friendly and tamper
I proof product along with the advantages of secureness, reliability, less cost,
I customer's satisfaction, and many more.
It will be appreciated by those skilled in the art that changes could be made to
the embodiments described above without departing fiom the broad inventive concept
thereof. The present embodiments are therefore to be considered in all respects as
illustrative and not restrictive, the scope of the invention being indicated by the
appended claims rather than by the foregoing description and all variations,
substitutions and changes which come within the meaning and range of equivalency
of the claims are therefore &tended to be embraced therein.

WE CLAIM:
1. A tamper-proof electronic energy meter 100 for measuring and displaying
electrical energy carried on power lines comprising:
.an energy meter base 104 comprising two side walls 108, a top wall 110 along
with a rear wall 112 resulting into a three sided envelop with fiont side and
bottom side open;
a printed circuit board assembly 130 fixed within the energy meter base 104;
a nameplate 136 mounted on the printed circuit board assembly 130;
a cylindrical meter cover 140 shaped to encompass the printed circuit board
assembly 130 and the nameplate 136 to get ultrasonically welded to the
energy meter base 104 thereby closing the fiont side of the energy meter base
' 104;
the cylindrical meter cover 140 sealed to the terminal cover assembly by a
latch mechanism 140 and a stopper 150;
a terminal cover assembly 102 secured fiom the bottom of the energy meter
base 104; wherein the terminal cover assembly 102 comprises of a terminal
cover 146 movable in a cam and follower 148 mechanism.
2. The tamper-proof electronic energy meter 100 as claimed in claim 1, wherein the
cylindrical meter cover 140 is additionally secured to the terminal cover
assembly 102 by a push seal comprising of the latch mechanism and the stopper.
3. The tamper-proof electronic energy meter 100 as claimed in claim 1, wherein the
terminal.cover assembly 102 includes the terminal cover 146 and terminals 142
embedded in a terminal block 144.
The tamper-proof electronic energy meter 100 as claimed in claim 1, wherein the
energy meter base 104 is provided with integrally molded PCB holders 118,
externally positioned push seal 122 and latch mechanism.
The tamper-proof electronic energy meter 100 as claimed in claim 1, wherein the
printed circuit board assembly 130 comprises of electrical/electronic components
including power cwent transformer, current transformer, primary wires, shunt,
capacitor, resistor, tact switches, and the like.
The tamper-proof electronic energy meter 100 as claimed in claim 1, wherein the
printed circuit board assembly 130 is attached to the bottom plate of the energy
meter base 104 by a snap-fit mechanism, a latch mechanism and the like.
The tamper-proof electronic energy meter 100 as claimed in claim 1, wherein the
nameplate 136 indicates the meter rating, brand' name, logo and other
information of the manufacturer, and the like.
The tamper-proof electronic energy meter 100 as claimed in claim 1, wherein the
nameplate 136 is provided with an elliptical hole through which an infia-red
communication device 138 protrudes that convey an instant and archived meter
reading of the electronic energy meter 100.
The tamper-proof electronic energy meter 100 as claimed in claim 1, wherein the
cylindrical meter cover 140 is provided with an aperture to project the infra-red
device 138 which is subsequently accessible through an infra-red cover.
10. The tamper-proof electronic energy meter 100 as claimed in claim 1, wherein the
terminal cover 146 is accessible to the authorized users for making electrical
connections between terminals 142 and the printed circuit board assembly 130.