High-voltage switches with arc preventing or extinguishing devic – Arc preventing or extinguishing devices – Polyphase
Reexamination Certificate
2001-12-03
2004-07-06
Donovan, Lincoln (Department: 2832)
High-voltage switches with arc preventing or extinguishing devic
Arc preventing or extinguishing devices
Polyphase
C218S120000, C218S140000
Reexamination Certificate
active
06759617
ABSTRACT:
BACKGROUND OF THE INVENTION
This non-provisional application claims priority under 35 U.S.C. § 119(a) on patent application No, 72907/2000 filed in Korea on Dec. 4, 2000, which is herein incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to a vacuum circuit breaker which is one of industrial electric devices used between submission and distribution of electricity on an industrial electric cable, and particularly, to a vacuum circuit breaker which is able to be installed in a narrow electrical power distributing cabinet by disposing a switching mechanism unit and an actuator unit in a lengthwise direction, and at the same time, the power of the actuator unit can be transmitted to a plurality of switching mechanism units evenly.
DESCRIPTION OF THE BACKGROUND ART
Generally, a breaker is a electric protective device which protects electric load devices and an electric power cable from a large accident current caused by an electrical shortage and a ground fault which may be generated on an electric circuit, and it performs a breaking operation automatically when such an accident current is generated, whereby the circuit is broken.
The vacuum circuit breaker is one of the breaker by which the circuit can be broken rapidly by extinguishing an arc in a vacuum chamber when the circuit is opened/closed and when the circuit is broken by a generation of the accident current.
Herein, a vacuum circuit breaker according to the prior art will be described as follows with reference to
FIGS. 1
,
2
, and
3
.
FIG. 1
is a front view showing the vacuum circuit breaker according to the prior art,
FIG. 2
is a side view showing the vacuum circuit breaker according to the prior art, and
FIG. 3
is a side cross sectional view showing an inner structure of the vacuum circuit breaker according to the prior art.
As shown in
FIGS. 1 and 2
, the vacuum circuit breaker according to the prior art comprises: three switching mechanism units
20
having stationary contacts and movable contacts respectively and corresponding to three-phases alternating current so as to make a main current to flow when normal state and to break the circuit when Ma large accident current is generated; an actuator unit
10
for providing the movable contact with dynamic power so that the circuit between the two contacts of the switching mechanism units
20
is opened/closed; and a supporting and transfer unit
30
for supporting the switching mechanism units
20
and the actuator unit
10
, and including transfer mechanisms for transferring the dynamic power from the actuator unit
10
to the switching mechanism units
20
to connect or break the circuit.
In the vacuum circuit breaker described above, the actuator unit
10
is located on front position in Figure, and the three switching mechanism units
10
are disposed on rear position of the actuator unit
10
in widthwise direction for the actuator unit
10
. And a supporting and transfer unit
30
is connected to lower parts of the actuator unit
10
and the switching mechanism unit
20
,
The inner structure of the vacuum circuit breaker according to the prior art will be described with reference to FIG.
3
. The inside of the vacuum circuit breaker comprises: a rotary shaft
31
which is rotated in order to transfer the dynamic power generated in the actuator unit
10
to the respective switching mechanism units
20
; a lever
32
connected to the rotary shaft
31
so as to be rotated with the rotary shaft
31
; a roller
33
coupled to an end of the lever
32
so as to be rotatable; a guide
37
coupled to the lever
32
and including an aperture
37
a
which provides a space in which the roller
33
is able to move in length direction; spring seats
36
and
36
′ installed on a outer circumference of the guide
37
; a compressive spring
35
for providing the roller
33
with an elastic force by being supported by the spring seats
36
and
36
′; a transfer lever
38
having one end connected lower end part of the guide
37
and the other end connected to the switching mechanism unit
20
for transmitting the dynamic power from the actuator unit
10
to the switching mechanisms unit
20
while rotating to clockwise direction or to counter-clockwise direction.
In more detail, an insulating rod
21
is coupled to the other end of the transfer lever
38
in vertical direction, and a movable contact
23
which is able to move to a position which contacts to the stationary contact
25
or to a position which is separated from the stationary contact
25
while vertically moving is disposed on upper end part of the insulating rod
21
.
Herein, three levers
32
, three rollers
33
, three guides
37
, three compressive springs
35
, and three transfer levers
38
are disposed in the actuator unit
10
and in the supporting and transfer unit
30
so as to transmit the dynamic power to the three respective switching mechanism units
20
, and the insulating rod
21
, the stationary contact
25
, and the movable contact
23
are disposed in the three switching mechanism units
20
.
The operation of the vacuum circuit breaker of the prior art will be described as follows.
When the actuator unit
10
rotates the rotary shaft
31
and the lever
32
to the clockwise direction so that a circuit between the two contacts
23
and
25
of the switching mechanism unit
20
is closed, the roller
33
compresses the compressive spring
35
and rotates the transfer lever
38
to the counter clockwise direction.
At that time, the insulating rod
21
goes up by the rotation of the transfer lever
38
to the counter clockwise direction, and then the movable contact
23
contacts to the stationary contact
25
, so the electrical circuit between the three phases alternative electric source and the electrical load devices is closed.
Also, if the rotary shaft
31
is further rotated to the clockwise direction after the movable contact
23
contacts to the stationary contact
25
, then the spring seat
36
′ abutted to the roller
33
is moved to lower position along with the outer circumference of the guide
35
and compresses the compressive spring
35
, the elastically energized spring
35
pushes up the insulating rode
21
of the switching mechanist unit
20
via transfer lever
38
, and then the contact between the two contacts
23
and
25
is maintained, whereby the turn-on operation of the vacuum circuit breaker is completed.
On the other hand, if the rotary shaft
31
and the lever
32
are rotated to counter clockwise direction, the roller
33
releases the compressed spring
35
and the transfer lever
38
is rotated to clockwise direction.
At that time, the insulating rod
21
is lowered by the rotation of the transfer lever
38
, and the movable contact
23
is separated from the stationary contact
25
then the circuit between the three phases alternative electric source and the electrical load devices is opened. Therefore, the circuit breaking operation of the vacuum circuit breaker is completed.
However, according to the conventional vacuum circuit breaker described above, the actuator unit
20
is located on front position and the three switching mechanism units
20
are located in widthwise direction. Therefore, if the vacuum circuit breaker is installed on rear inside portion of a electrical power distributing cabinet (not shown) which has complex and limited installation space, it is difficult to ensure the installation space inside the power distributing cabinet, and to maintain and repair the vacuum circuit breaker because the space in the power distributing cabinet is limited.
Also, according to the vacuum circuit breaker of the prior art, the power transmitting mechanisms such as the transfer lever
38
for transmitting the dynamic power from the actuator unit
10
to the switching mechanism units
20
are respectively disposed on the three switching mechanism units
20
, and therefore the entire number of components is increased and the structure of the apparatus becomes complex. In addition, if the transmitting speed of the po
Birch Stewart Kolasch & Birch
Donovan Lincoln
LG Industrial Systems Co. Ltd.
LandOfFree
Vacuum circuit breaker does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Vacuum circuit breaker, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vacuum circuit breaker will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3233426