Title of the invention
The present invention is related to a system for Air-Break Full
Load Break Switch with motor and/or manual mechanism. More
particularly the invention is air-break full load break switch
which is capable of breaking full rated current and voltage
without the use of any gas or vacuum as interrupting or
isolating media.
Background of the invention
Traditional switches for medium and high voltage applications
cannot operate on full-load (rated voltage along with rated
current). The only equipment that can operate such a load is a
vacuum circuit breaker. In case of faults or maintenance of the
lines, the user has to shut off the circuit breaker followed by
the traditional switch leading to black-out of even the areas
where there is no maintenance required. (Limitation)
The traditional switch uses multiple linkage assemblies to
enable the user to operate the switch from the ground, also
leading to chances of mal-operation.
The traditional switch forms a weak contact between the fixed
and moving contacts which gets worse after every operation hence
leading to pitting between the contacts resulting in heavy power
losses.
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The alignment of the switch is disturbed after every operation,
leading to mal-operation after a few operations. The moving
contact's fitting into the fixed contact completely depends on
the level of the moving contact with respect to the fixed
contact at the time of operation. This level is can be disturbed
due to many internal and external reasons and can lead to
malfunctioning.
Significance of the invention
The main significance of the present invention to provide Full
Load Break Switch with motor and/or manual mechanism which is
used only air. Oil / SF6 or any kind of liquid or gas is not
used for interruption or insulation purposes. The use of only
air and not any other element helps in reducing the maintenance
cost and manufacturing cost of the load break switch.
This load break switch is operate-able by a manual linking rod
or motor operating mechanism. There is a visible gap of switch
after opening to produce functions of isolation and protection.
The switch opens or closes under rated load current and not
require any secondary protection device.
The present invention is an upgrade to conventional isolators
which could not operate on full load, could not be operated
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remotely through SCADA (Supervisory Control And Data
Acquisition) and had demanded maintenance due to many linkages.
The present invention can be operated on full-load remotely
through SCADA (Supervisory Control And Data Acquisition) and has
a trouble-free performance due to its minimum linkage mechanism.
The load break switch is not susceptible to vandalism when
compared to traditional isolators and switches.
Object of the invention:
The main object of the invention is to develop a Air-Break full
load break system using only air for insulation or interruption
purpose.
Another object of the invention is to provide a Air- break load
break full load break switch using air with low maintenance cost
and low manufacturing cost.
Further Another object of the invention is to upgrade to
conventional isolators which could be operated on full-load
remotely through SCADA (Supervisory Control And Data
Acquisition) and has a trouble-free performance due to its
minimum linkage mechanism.
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Summary of the invention
According to the present invention, A system for air break full
load break switch comprising three phases installed on one base
and joint together with one inter phase drive shaft to ensure
synchronous closing and opening of the three phases, insulators
of high strength, driving shaft, opening shaft, a mechanical
stopper connected nearest to the end of the opening shaft,
operating insulators fitted on a drive shaft, moving contacts,
terminal pads, spring mechanism, an actuator, an arc returning
ring, an arcing chamber.
Another embodiment of the invention, Base made of mild steel,
stainless steel, aluminium or any other high strength material
capable of handling the weight of the rest of the parts and the
vibrations and jerks caused during operation of the switch.
A system for air break full load break switch as claimed claim
1, wherein the said base fitted with insulators to provide
necessary insulation from live part of the earth.
Another embodiment of the invention, drive shaft connected to
one side of the base through a spring actuated mechanism
comprising a a solid or hollow rod of any shape.
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Another embodiment of the invention, moving contact are fitted
with a form of spring mechanism to ensure proper contact with
the fixed contacts.
Another embodiment of the invention, mechanical stopper is
shaped in any way that it rotates along with the operating shaft
but can stop the movement when the limit is reached.
Another embodiment of the invention, phase comprising 2 or 3
insulators, out of which 1 or 2 insulators connected with fixed
contact and pads and one 1 insulator for operation of the moving
contact.
Another embodiment of the invention, arcing chamber made of
insulating material with high electric performance having high
mechanical strength comprises a built in spring with fast acting
mechanism and conductive contacts.
Summary of the drawings:
A more complete appreciation of the invention and the attachment
advantages thereof will be more clearly understood by reference
to the following accompanying drawings which are for
illustrative purpose, hence the same should not be construed to
restrict the scope of the invention.
Fig 1 illustrates general Arrangement of load break switch
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Fig 2 illustrates Base channel
Fig 3 illustrate post & operative insulator
Fig 4 illustrate fixed contact
Fig 5 illustrate terminal pad
Fig 6 illustrate drive shaft gun metal bush
Fig 7 illustrate spring actuated mechanism
Fig 8 illustrate operating system
Fig 9 illustrate mechanical stopper
Fig 10 illustrate operating handle
Fig 11 illustrate Motor
Fig 12 illustrate Auxiliary switch
Fig 13 illustrate limit switch
Fig 14 illustrate motor & gear box
Fig 15 illustrate gear box
Fig 16 illustrate Moving contact
Fig 17 illustrate terminal clamp
Fig 18 illustrate Actuator
Fig 19 illustrate Arc return ring
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Fig 20 illustrate Arching chamber
Fig 21 illustrate Switch on –off position
Fig 22 Intermediate Position
Detailed description of the invention
According to figure no- 1, there are three phases named as The
R ,Y , B of the load break switch is installed on one base,
(1.1) joint together with one inter-phase drive shaft (1.2) to
ensure synchronous closing and opening of the three phases.
According to fig. no 1, the base can be made of mild steel,
stainless steel, aluminium or any other high strength material
capable of handling the weight of the rest of the parts and the
vibrations and jerks caused during operation of the switch.
According to fig.1 ,The base (1.1 ) is then fitted with
insulators (1.3) on each phase to provide necessary insulation
from the LIVE part to the earth. The insulators (1.3 ) have
characteristics which provides adequate insulation for the
intended usage of the switch. Each phase has either 2 or 3
insulators - 1 or 2 insulators are for fixed contacts (1.4 ) and
pads (1.5 ) and 1 for operation of the moving contact. The
insulators can be made of either porcelain or polymer material
having enough mechanical strength to endure the vibrations
caused during the operation of the switch.
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The height of the insulator (1.3 ) must be enough to not cause
any short circuit between the LIVE and the earth of the power
line. The distance between the insulators (1.3 ) of each phase
must be enough to not cause any short circuit between any of the
phases.
According to Fig 1 , The base (1.1) is fitted with the drive
shaft (1.2) supported by bushes (1.6) made of brass, gunmetal,
PVC or any other material fit for the purpose. The drive shaft
is connected to 3 operating insulators (one for each phase).
According to fig: 1 , the drive shaft(1.2) is connected to one
side of the base(1.1) through a spring actuated mechanism(1.7).
The spring actuated mechanism (1.7) gives stability to the whole
switch by keeping the 3 phases at inertia. The springs (1.8)
are angled in a way that it takes adequate pressure to charge
them with ease but at the same time it generates enough pressure
to operate the switch with a great speed. The springs(1.8) can
be made of spring steel, stainless steel, mild steel, brass or
any other material capable of withstanding the high pressure.
The drive shaft (1.2) may be made of a solid or hollow rod of
any shape enough to endure the movement of the 3 phases along
with the heavy spring pressure.
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According to fig :1 , A mechanical stopper (1.9) made of high
strength steel is connected nearer to the end of the operating
shaft (1.2) and placed such that the switch does not over travel
during opening. The mechanical stopper(1.9) is shaped in a way
that it can rotate along with the operating shaft (1.2) but can
stop the movement when the limit is reached.
According to FiG: 1, The drive shaft (1.2) is extended out of
the base(1.1) such that it can connect to a manual operating
handle(1.10) and the motor mechanism which may either be on the
same or opposite sides of the operating shaft(1.2). The
operating handle(1.10) is connected to the operating shaft(1.2)
in a way that it cannot slip / over travel / under travel, and
always moves with the movement of the operating shaft(1.2).
The operating handle(1.10) may be made of mild steel, stainless
steel or any other material which has enough strength to endure
the torque it has to go through to charge the springs(1.8 ) and
operate the switch. The handle (1.10) can be of any size, shape
and length, enough to make it easy for the operator to manually
operate the switch with adequate effort.
According to Fig: 1, The motor mechanism consists of a motor
(1.11 ), a gear, a set of auxiliary switches (1.12 ) and limit
switches (1.13). This whole assembly is housed inside a closed
box to prevent the assembly from dust and water. The closed
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box (1.14) may be made of any material enough to endure the
purpose as defined above. The motor (1.11 ) may be AC or DC and
may range across any rpm and operating voltage as long as it can
support the torque required to operate the switch. The gear
(1.15) may be of a suitable material, ratio and workmanship such
that it can connect to the operating shaft and the motor output
and provide adequate torque to operate the switch. The auxiliary
switch (1.12) and limit switches (1.13) may be of any make and
size but must endure a large number of operations without being
replaced.
There is no connecting rods / operating rods / down pipe which
connects the switch mechanism to the control box.
According to Fig:1 , The motor (1.11 ) and gears(1.15) are
fitted with the switch on the pole with only wires coming down
for connection with the control box. The motor mechanism is fit
to the switch in such a way that it can be removed or added as a
separate module without any change to any part of the switch.
According to fig: 1, The operating insulators fitted on the
drive shaft (1.2) are connected to the moving contact (1.16) on
the other end. Each switch consists of 3 moving contacts (one
for each phase). The moving contact can be of any material,
shape and size enough to make sure that it can carry the
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required current without excessive heating / melting / power
losses.
The moving contact must be fitted with a form of spring
mechanism (1.7) to ensure proper contact with the fixed
contacts. The other end of the moving contact must be connected
to the terminal pads (1.5) through a conducting material of
adequate size to ensure enough cross section for current passage
through it.
According to Fig: 1 , Each switch consists of 3 fixed contacts
(1.4) and 6 terminal pads (1.5) Terminal pads may be an
extension of the fixed contacts to save extra connections. The
terminal pads (1.5) and fixed contacts (1.4) must be made of
any material, shape and size enough to make sure that it can
carry the required current without excessive heating / melting /
power losses. The moving contact (1.16) must fit into the fixed
contact (1.4) to form a good stable contact such that there are
no loose connections leading to pitting and power losses.
The terminal pads (1.5) must have provision to be connected to
terminal clamps (1.17) through nuts and bolts.
According to Fig: 1 , The moving contacts (1.16) must be fit
with an actuator(1.18) and a Arc return ring (1.19) which would
hit the arcing chambers (1.20) causing the arc to be
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extinguished during opening / closing. The arcing chamber (1.20
) is made of a material which has high mechanical strength and
is resistant to catching fire. The arcing chamber (1.20 ) is
made of insulating material with the merits of high electric
performance, arc-endurance and high strength. The chamber has a
built-in spring with fast acting mechanism which ensures
breaking of load current, hence being free from operating speed
of the user. The arcing gap and disconnect gap of the load
break switch is parallel in the course of opening and closing.
Being the heart of the load break switch, it is capable of
extinguishing the arc formed when operated on full load. There
is no need of external energy or HV/LV solenoids for holding the
position CLOSE or OPEN.
According to Fig:1 The arcing chamber (1.20) consists of a
spring mechanism which is actuated through the actuator (1.16)
fitted on the moving contacts (1.16). The arcing chamber (1.20)
encloses conductive contacts, preferably made of an alloy of
copper, which make and break inside it at high speeds such that
the arc is extinguished. Also, the material of the chamber
prevents the arc from being spread or persist long enough to
cause any damage to the contacts.
Provisions are included for electrical close, and electrical and
manual trip. Each pole of the LBS (1) is identical to allow
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complete replacement of any individual pole , without
disassembly or replacement of the other poles. All parts must
are field replaceable. The LBS is suitable for mounting on
channel on D.P. Structure.
Operation
According to the Fig: , the full Load break switch consists
insulators (1.3), moving contacts (1.16 ), fixed contacts (1.4
), operating shaft (1.2 ), spring mechanism (1.7 ), operating
shaft (1.2), operating handle (1.10), motor mechanism (1.14),
base (1.1 ) and arcing chambers (1.20 ).
The dimensions given are subject to change based on the voltage
level the switch is used in.
When the operating handle (1.10) is rotated, it charges the
spring (1.8) during the first half of the operation. Once the
spring (1.8) is charged, it automatically opens / closes the
switch with quick speed and actuates the arcing chamber (1.20)
along with its motion. Figure (1.24) show the handle (1.10 ) in
initial and final position in ON and OFF positions respectively.
When the spring (1.8) is being operated, the switch (1) assumes
an intermediate position as shown in figure (1.22)
The arc is being transferred from the main contact (1.16) to the
arcing chamber (1.20 ) at the time of opening in a way that the
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current gets routed through the arcing chamber (1.20) just as
the main contacts (1.16 ) are being broken. This takes place
through the copper/brass arc return ring (1.19 ) which gets into
contact with the arcing chamber (1.20 ) from the outside as per
Figure 1.
Figure -1 shows the position and direction of the current during
the time of closing of the contact.
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Claims:
We claim:
1. A system for full load break switch comprising three
phases installed on one base and joint together with one
inter phase drive shaft to ensure synchronous closing and
opening of the three phases, insulators of high strength,
driving shaft, opening shaft connected to one side of
base, a mechanical stopper connected nearest to the end
of the opening shaft, operating insulators fitted on a
drive shaft, moving contacts fitted with a form of spring
mechanism to ensure proper contact with the fixed
contact, terminal pads having provision to be connected
to terminal clamps, spring mechanism, an actuator, an
arc returning ring and an arcing chamber made of a
insulating material with high mechanical strength .
2. A system for full load break switch as claimed claim 1,
wherein the said base made of mild steel, stainless
steel, aluminium or any other high strength material
capable of handling the weight of the rest of the parts
and the vibrations and jerks caused during operation of
the switch.
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3. A system for full load break switch as claimed claim 1,
wherein the said base fitted with insulators to provide
necessary insulation from live part of the earth.
4. A system for full load break switch as claimed claim 1,
wherein the said drive shaft connected to one side of
the base through a spring actuated mechanism comprising a
a solid or hollow rod of any shape .
5. A system for full load break switch as claimed claim 1,
wherein the moving contact are fitted with a form of
spring mechanism to ensure proper contact with the fixed
contacts.
6. A system for full load break switch as claimed claim 1,
wherein the said mechanical stopper is shaped in any way
that it rotate along with the operating shaft but can
stop the movement when the limit is reached.
7. A system for full load break switch as claimed claim 1,
wherein the said phase comprising 2 or 3 insulators, out
of which 1 or 2 insulators connected with fixed contact
and pads and one 1 insulator for operation of the moving
contact.
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8. A system for full load break switch which is claimed in
claim 1, wherein the said arcing chamber made of
insulating material with high electric performance
having high mechanical strength comprises a built in
spring with fast acting mechanism and conductive
contacts.
9. A system for full load break switch substantially as
hereinbefore described with the reference of accompanying
drawings.