RELATED APPLICATION
BACKGROUND OF THE INVENTION
1. Field of the Invention
[0002] The present disclosure relates to a switching mechanism for an air circuit breaker
and toggle links thereof, and more particularly, to a switching mechanism for an air
circuit breaker capable of enhancing operational reliability by preventing interference
between links, and toggle links thereof.
2. Description of the Background Art
[0003] US-A-5 224 590 discloses a circuit breaker having a contact movable between open and closed positions,
including a closing spring assembly having a closing spring and first and second brackets.
The closing spring assembly is chargeable when in a reset position in which the first
bracket is hooked by a first hook.
[0004] EP-A-1 130 615 discloses a latching- or breaker-mechanism for an LV circuit-breaker with a closing
latch supported on a closing half-shaft, and an opening latch supported on a release
half-shaft. Each half-shaft is equipped with journals at either end and has a metallic
central shaft which carries various functional elements jutting out radially.
[0005] Generally, an air circuit breaker serves as a low voltage type circuit beaker that
performs a turning on/off of load circuit or a circuit breaking operation in the occurrence
of an abnormal current such as a short circuit, a ground fault, and an excess current.
[0006] In the conventional air circuit breaker, toggle links may be deformed or damaged
due to an uneven assembled state therebetween, or due to collision or interference
between side surfaces thereof at the time of a charging operation by a closing spring
and a closing operation.
[0007] As the toggles links are deformed and damaged, deviation severely occurs between
opening and closing operations of the air circuit breaker. Due to unbalance in a three-phase
current and a voltage supplied to a load when the air circuit breaker performs opening
and closing operations, the load is overheated or damaged. Furthermore, the life-span
of the air circuit breaker is lowered.
SUMMARY OF THE INVENTION
[0008] Therefore, an object of the present disclosure is to provide a switching mechanism
for an air circuit breaker capable of enhancing operational reliability by preventing
damage or deformation of toggle links due to interference therebetween, and toggle
links thereof.
[0009] To achieve these and other advantages and in accordance with the purpose of the present
disclosure, as embodied and broadly described herein, there is provided a switching
mechanism for an air circuit breaker according to claim 1.
[0010] To achieve these and other advantages and in accordance with the purpose of the present
disclosure, as embodied and broadly described herein, there is also provided toggle
links of a switching mechanism for an air circuit breaker according to claim 2.
[0011] The foregoing and other objects, features, aspects and advantages of the present
disclosure will become more apparent from the following detailed description of the
present disclosure when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The accompanying drawings, which are included to provide a further understanding
of the invention and are incorporated in and constitute a part of this specification,
illustrate embodiments of the invention and together with the description serve to
explain the principles of the invention.
[0013] In the drawings:
FIG. 1 is a sectional view of a switching mechanism for an air circuit breaker according
to the present invention;
FIG. 2 is a sectional view showing a compressed state of a closing spring of the switching
mechanism for an air circuit breaker according to the present invention;
FIG. 3 is a sectional view showing a closed-circuit state of the switching mechanism
for an air circuit breaker according to the present invention; and
FIG. 4 is a perspective view showing toggle links of the switching mechanism for an
air circuit breaker according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0014] Reference will now be made in detail to the preferred embodiments of the present
disclosure, examples of which are illustrated in the accompanying drawings.
[0015] Hereinafter, a switching mechanism for an air circuit breaker according to the present
invention, and toggle links thereof will be explained in more detail with reference
to the attached drawings.
[0016] As shown in FIGS. 1 to 3, a switching mechanism 2 for an air circuit breaker according
to the present invention comprises a stationary contactor 39, a movable contactor
38, a main shaft 3, a main shaft lever 40, a closing spring 25, a driving lever 24,
toggle links 29, 34 and 35.
[0017] The toggle links 29, 34 and 35 are referred to as first, second, and third links,
respectively.
[0018] The stationary contactor 39 is connected to a power source side circuit or a load
side circuit in each of three phases such as R, S and T, and is disposed according
to each phase. When the air circuit breaker is implemented as an air circuit breaker
for a three-phase alternating current of R, S and T, the stationary contactor 39 is
disposed according to each phase.
[0019] The movable contactor 38 is disposed so as to correspond to the stationary contactor
39. That is, when three stationary contactors 39 are provided, three movable contactors
38 are provided. The movable contactor 38 is movable to a closing position to contact
the stationary contactor 39, or to an opening position to be separated from the stationary
contactor 39.
[0020] The main shaft 3 is rotatable so as to provide a driving force to move the plurality
of movable contactors (i.e., three movable contactors) simultaneously to the closing
position or the opening position.
[0021] The main shaft lever 40 is coaxially disposed on the main shaft 3, and has one end
connected to the movable contactor.
[0022] The closing spring 25 provides a driving energy to drive the movable contactor 38
to the closing position.
[0023] The driving lever 24 is connected to the closing spring 25, and is rotatable by the
driving energy from the closing spring 25.
[0024] The first link 29 is rotatable, and one end thereof is connected to the driving lever
24 so as to interlock therewith.
[0025] The second link 34 is rotatable by interlocking with the first link 29, and includes
two plate members 34a and 34b. The second link 34 has an extension portion 55 extended
so as to prevent interference with the first link 29 by positioning the first link
29 between the plate members 34a and 34b. The extension portion 55 is composed of
one pair of extension portions 55a and 55b disposed at the plate members 34a and 34b,
respectively.
[0026] The third link 35 has one end connected to the second link 34, and the other end
connected to the main shaft lever 40. The third link 35 is rotated together with the
second link 34 so as to drive the movable contactor 38 to the closing position, thereby
rotating the main shaft lever 40.
[0027] As shown in FIGS. 1 to 3, the switching mechanism 2 for an air circuit breaker according
to the present invention further comprises a rotation shaft 21, a cam 22, one pair
of side plates 9, a first latch 27, an on-lever 28, a latch roller 30, a second latch
31, an off-lever 32, a connecting shaft 36, an opening spring 37, and a lower terminal
39-1.
[0028] The cam 22 is installed on the rotation shaft 21 thus to be rotated manually or automatically.
Namely, the rotation shaft 21 is connected to a manual handle or a motor (not shown)
thus to be manually rotated or to be electrically driven.
[0029] One pair of side plates 9 supports the switching mechanism 2 at both sides.
[0030] The driving lever 24 is rotatably supported between the two side plates 9, and is
rotated by interlocking with the first link 29 coaxially installed with the cam 22
and the rotation shaft 21.
[0031] One end of the closing spring 25 is supported by a spring seat (not shown), and the
other end thereof is supported by a spring support bracket (not shown). The spring
seat is connected to a lower end of the driving lever 24, and the spring support bracket
is fixedly installed at the side plates 9. The driving lever 24 is rotated as the
cam 22 rotates, and thus the spring seat is moved in the left direction of FIGS. 1
to 3. Here, the closing spring 25 is compressed by the spring seat being moved in
the left direction, thereby charging an elastic energy.
[0032] The first latch 27 is extended in upper and lower directions, and is biased so as
to elastically rotate in one direction by a spring (a reference numeral not designated)
connected between a pin fixed to the side plate 9 and the first latch 27. In order
to prevent rotation of the cam 22 occurred while the elastic energy of the closing
spring 25 charged at the time of the charging operation is discharged, the first latch
27 latches or locks the cam 22 by contacting thereto.
[0033] The on-lever 28 is rotatably installed above the first latch 27 so as to lock or
release the first latch 27.
[0034] The first link 29 has an 'L' shape, and is rotatable centering around a central shaft
(not shown) fixedly installed at the side plate 9. A lower horizontal extension portion
of the first link 29 is connected to the second link 34. A groove 49 for getting in
or getting out a latch roller 30 of the second latch 31 so as to lock or release the
first link 29 is formed at an upper end of the first link 29.
[0035] The second latch 31 is disposed above the first link 29 with a nearly 'V' shape.
The latch roller 30 is rotatably installed at a central portion of the second latch
31 in a length direction. The second latch 31 is biased so as to rotate in one direction
by a bias spring (a reference numeral not designated) connected between a pin (a reference
numeral not designated) fixed to the side plate and the second latch 31. Accordingly,
when the latch roller 30 gets into the groove 49 of the first link 29, the second
latch 31 is locked by the first link 29. On the contrary, when the latch roller 30
is drawn out (gets out) of the groove 49 of the first link 29, the second latch 31
is released thus to rotate by the bias spring in one direction , i.e., a counterclockwise
direction in FIGS. 1 to 3.
[0036] The off-lever 32 is disposed above the second latch 31, and is rotatable centering
around a central shaft fixed to the side plate 9. The off-lever 32 is rotatable to
a position to lock the second latch 31 or to release the locking of the second latch
31. As means to rotate the off-lever 32, there may be provided an off-button operated
by a user's pressing, and an off-coupling connected between the off-button and the
off-lever 32 so as to transmit a displacement of the off-button to the off-lever 32.
The off-button and the off-coupling were not shown.
[0037] A lower end of the second link 34 is connected to the driving lever 24 so as to interlock
therewith together with the first link 29. The second link 34 comes in contact with
a pin 33 provided at the driving lever 24, and one side surface thereof is pushed
by the pin 33.
[0038] The third link 35 is connected to an upper end of the second link 34, and is rotatable
together with the second link 34 according to a displacement of the second link 34.
[0039] The main shaft 3 is extended to penetrate the side plate 9. The main shaft lever
40 is connected to the third link 35, and is installed on the main shaft 3 so as to
rotate together with the main shaft 3. Accordingly, as the third link 35 rotates clockwise
or counterclockwise, the main shaft lever 40 rotates counterclockwise or clockwise,
and thus the main shaft 3 rotates counterclockwise or clockwise.
[0040] The connecting shaft 36 serves to connect the third link 35 to the main shaft 3 for
interlocking therebetween.
[0041] One end of the opening spring 37 is supported by the connecting shaft 36, and the
other end thereof is supported by one fixing pin (a reference numeral not designated)
fixed onto the side plate 9. Referring to FIG. 3, the main shaft lever 40 rotates
counterclockwise in the closing position of the air circuit breaker, and thus the
connecting shaft 36 is moved to the left side in drawing (i.e., towards the stationary
contactor 39). Accordingly, the opening spring 37 is extended to charge an elastic
energy. Under this state, when the off-button is pressed by a user, the off-lever
32 rotates clockwise as shown in FIG. 1 to release the second latch 31. Accordingly,
the second latch 31 rotates counterclockwise in drawing, and the latch roller 30 is
drawn out of the groove 49 of the first link 29. Here, the main shaft lever 40 and
the main shaft 3 rotate counterclockwise by discharging the elastic energy of the
opening spring 37, and thus the third link 35 and the second link 34 rotate clockwise.
[0042] The main shaft lever 40 is coaxially connected onto the main shaft 3 so as to rotate
together therewith and is connected with the movable contactor 38. When the main shaft
lever 40 is rotated counterclockwise, the movable contactor 38 is separated from the
stationary contactor 39 following the main shaft lever 40 to implement an open- circuit.
On the contrary, when the main shaft lever 40 rotates clockwise on the drawing, the
movable contactor 38 is moved to contact the stationary contactor 39 following the
main shaft lever 40. Accordingly, a closed circuit is formed between the power source
and the load thus to flow a current.
[0043] The lower terminal 39-1 is connected to the movable contactor 38 through an electric
conductor (not shown), and is electrically connected to the load or the power source.
Accordingly, when the movable contactor 38 comes in contact with the stationary contactor
39, a closed-circuit is implemented between the power source and the load thus to
flow a current. On the contrary, when the movable contactor 38 is separated from the
stationary contactor 39, an open-circuit is implemented between the power source and
the load thus to prevent a current flow.
[0044] The toggle links of the switching mechanism for an air circuit breaker according
to the present invention will be explained in more detail with reference to FIG. 4.
[0045] As shown in FIG. 4, the toggle links of the switching mechanism for an air circuit
breaker according to the present invention perform a toggling operation to endure
a repulsive load occurred at the time of a closing operation. The toggle links include
the first link 29, the second link 34, and the third link 35.
[0046] The first and second links 29 and 34 are connected to each other by a first connection
pin 41, and the second and third links 34 and 35 are connected to each other by a
second connection pin 42 fixed to the third link 35. Referring to FIGS. 1 to 3, the
first connection pin 41 is extended to be connected up to the driving lever 24, thereby
connecting the first and second links 29 and 34 to the driving lever 24 for interlocking
with the driving lever 24.
[0047] In order to prevent the first and second links 29 and 34 from colliding to each other
by an interference at the time of a closing operation and an opening operation of
the air circuit breaker, the second link 34 includes a first plate member 34a and
a second plate member 34b. Also, the first plate member 34a and the second plate member
34b are disposed to be separated from each other by a predetermined distance therebetween.
Also, the first link 29 is disposed between the first plate member 34a and the second
plate member 34b. The reference numeral 52 denotes a side surface of the first link
29 facing the second link 34 in a thickness direction.
[0048] Despite the above configuration, the first and second links 29 and 34 may collide
with each other while the air circuit breaker is operated, due to the following reasons,
such as an assembly error and an uneven load at the time of a charging operation for
the closing spring, a closing operation, or an opening operation.
[0049] In order to prevent the first and second links 29 and 34 from colliding to each other
by interference at the time of a charging operation for the closing spring, a closing
operation, or an opening operation, the second link 34 is provided with an extension
portion 55 extended towards the first link 29 and allowing the first link 29 to be
disposed between the first plate member 34a and the second plate member 34b. The extension
portion 55 is composed of an extension portion 55a of the first plate member 34a,
and an extension portion 55b of the second plate member 34b.
[0050] The extension portion 55 of the second link 34 maintains an interposed state of the
first link 29 between the first and second links 34a and 34b when the air circuit
breaker is operated to charging, closing, and opening, thereby preventing interference
or collision between the first and second links 29 and 34.
[0051] The switching mechanism 2 for the air circuit breaker according to the present invention
performs a charging operation, a closing operation, and an opening operation. More
concretely, the switching mechanism 2 performs a charging operation for charging an
elastic energy to the closing spring 25, a closing operation for contacting the movable
contactor 38 to the stationary contactor 39 by using the elastic energy charged to
the closing spring 25, and an opening operation for separating the movable contactor
38 from the stationary contactor 39 by using the elastic energy charged to the opening
spring 37.
[0052] With reference to FIG. 2, will be explained the operation for charging the closing
spring 25 of the air circuit breaker so as to perform a closing operation under a
state that the movable contactor 38 has been separated from the stationary contactor
39. As shown in FIG. 2, the rotation shaft 21 is rotated counterclockwise by manually
operating a handle (not shown) provided at the rotation shaft 21 by a user, or by
automatically operating the rotation shaft 21 by a motor (not shown) connected thereto.
Accordingly, the cam 22 is rotated counterclockwise, and thus the first link 29 coaxially
connected with the cam 22 and the rotation shaft 21 is rotated. Under this state,
the driving lever 24 connected with one end of the first link 29 compresses the closing
spring 25 through the spring seat (not shown) while being rotated. Accordingly, an
elastic energy for a closing operation is charged to the closing spring 25.
[0053] Hereinafter, a closing operation of the air circuit breaker will be explained with
reference to FIG. 3.
[0054] When a user presses a closing button (not shown), the on-lever 28 interlock connected
to the closing button is rotated counterclockwise. Accordingly, the first latch 27
is released, and is rotated in one direction by a bias spring supported at the side
plate 9. As a result, the locked state of the cam 22 by the first latch 27 is released.
By a discharge elastic energy of the closing spring 25, the driving lever 24 is rotated
counterclockwise. Accordingly, the first link 29 having one end connected to the driving
lever 24 is rotated counterclockwise, and thus the second and third links 34 and 35
are rotated counterclockwise. Under this state, the main shaft lever 40 is rotated
clockwise, and thus the movable contactor 38 connected to the main shaft lever 40
comes in contact with the stationary contactor 39. As a result, the closing operation
of the air circuit breaker is completed.
[0055] During the closing operation, the closing spring 37 is extended as the connecting
shaft 36 provided at the main shaft lever 40 is moved in the left direction, thereby
charging an elastic energy for the closing operation.
[0056] Next, an opening operation of the air circuit breaker will be explained with reference
to FIG. 1.
[0057] When a user presses the off-button, the off-lever 32 is rotated clockwise as shown
in FIG. 1 to release the second latch 31. Accordingly, the second latch 31 is rotated
counterclockwise, and the latch roller 30 is drawn out of the groove 49 of the first
link 29. Here, the main shaft lever 40 and the main shaft 3 are rotated counterclockwise
by the discharge elastic energy of the opening spring 37, and thereby the second and
third links 34 and 35 are rotated clockwise. Accordingly, the movable contactor 38
connected to the main shaft lever 40 is separated from the stationary contactor 39,
thereby implementing an open-circuit between the power source and the load.
[0058] During the charging operation, the closing operation, and the opening operation,
the first, second, and third links 29, 34 and 35 perform a toggling operation. Since
the extension portions 55a and 55b of the second link 34 are located so as to interpose
the first link 29 therebetween, an uneven assembled state among the toggle links 29,
34 and 35 is prevented, and interference or collision between the first and second
links 29 and 34 while the air circuit breaker is operated is prevented.
[0059] In the air circuit breaker according to the present invention, the second link 34
comprises a pair of plate members, and the extension portions disposed at each end
of the plate members and extended to locate the first link 29 between the plate members.
Accordingly, while the air circuit breaker is operated, interference or collision
between the first and second links 29 and 34 is prevented thus to prevent deformation
or damage of the toggle links. As a result, the air circuit breaker has an enhanced
reliability and a long life-span.
1. Schaltmechanismus (2) für einen Druckluftschalter, umfassend:
einen stationären Schaltschütz (39), der mit einer Energiequellenstammleitung oder
einer Laststammleitung für jede Phase verbunden ist, und entsprechend jeder Phase
bereitgestellt ist;
einen beweglichen Schaltschütz (38), der zum Korrespondieren mit dem stationären Schaltschütz
angeordnet ist, und beweglich in eine geschlossene Position zum Kontaktieren des stationären
Schaltschütz, oder in eine offene Position, um von dem stationären Schaltschütz getrennt
zu sein;
eine Hauptwelle (3), die drehbar gestaltet ist, um eine Antriebskraft zur Bewegung
des beweglichen Schaltschütz (38) in die geschlossene Position oder die offene Position
bereitzustellen;
einen Hauptwellenhebel (40), der koaxial auf der Hauptwelle (3) angeordnet ist, und
von dem ein Ende mit dem beweglichen Schaltschütz (38) verbunden ist;
eine Schließfeder (25), um eine Antriebsenergie zur Bewegung des beweglichen Schaltschütz
(38) in die geschlossene Position bereitzustellen;
einen Antriebshebel (24), der mit der Schließfeder (25) verbunden ist, und durch die
Antriebskraft drehbar ist, die durch die Schließfeder (25) bereitgestellt wird;
eine erste Verbindung (29), die drehbar gestaltet ist und deren eines Ende mit dem
Antriebshebel (24) verbunden ist, um damit zu verriegeln;
eine zweite Verbindung (34), die durch Verriegeln mit der ersten Verbindung (29) drehbar
ist, mit zwei Plattenbauteilen (34a, 34b) und einem Paar Ausdelnungsabschnitte (55)
in Richtung der ersten Verbindung (29), um ein Zusammenwirken mit der ersten Verbindung
(29) zu verhindern, durch Beibehaltung einer Zwischenposition der ersten Verbindung
(29) zwischen den zwei Plattenbauteilen (34a, 34b); und
eine dritte Verbindung (35) mit einem Ende, welches mit der zweiten Verbindung (34)
verbunden ist, wobei das andere Ende mit dem Hauptwellenhebel (40) verbunden ist und
sich zusammen mit der zweiten Verbindung (34) dreht, um den beweglichen Schalter (38)
in die geschlossene Position zu bewegen, um den Hauptwellenhebel (40) zu drehen.
2. Gelenkverbindung für einen Schaltmechanismus (2) für einen Druckluftschalter, umfassend:
eine erste Verbindung (29), die drehbar gestaltet ist;
eine zweite Verbindung (34), deren eines Ende mit der ersten Verbindung (29) verbunden
ist und durch Entladen einer elastischen Energie einer Schließfeder (25) drehbar ist,
und ein Paar Ausdehnungsabschnitte (55) aufweist, die sich in Richtung der ersten
Verbindung (29) erstrecken, um ein Zusammenwirken mit der ersten Verbindung (29) zu
verhindern, durch Beibehaltung einer Zwischenposition der ersten Verbindung (29) dazwischen;
und
eine dritte Verbindung (35) mit einem Ende, welches mit der zweiten Verbindung (34)
verbunden ist und sich mit der zweiten Verbindung (34) zusammen dreht, um den beweglichen
Schalter (38) in die geschlossene Position zu bewegen.
3. Gelenkverbindung eines Schaltmechanismus (2) für einen Druckluftschalter nach Anspruch
2, bei welcher die erste Verbindung (29) ein Plattenbauteil ist und die zweite Verbindung
(34) ein Paar Plattenbauteile einschließt, die angeordnet sind, um voneinander durch
eine zuvor festgelegte Entfernung getrennt zu sein.
1. Un mécanisme de commutation pour un coupe-circuit à air, comprenant :
un contacteur fixe (39) relié à un circuit côté source d'alimentation ou à un circuit
côté charge pour chaque phase, et prévu conformément à chaque phase ;
un contacteur mobile (38) disposé pour correspondre au contacteur fixe, et mobile
vers une position de fermeture pour venir en contact avec le contacteur fixe, ou vers
une position d'ouverture pour être séparé du contacteur fixe ;
un arbre principal configuré pour être mobile en rotation, pour procurer une force
d'entraînement de manière à déplacer le contacteur mobile (38) vers la position de
fermeture ou vers la position d'ouverture ;
un levier d'arbre principal (40) disposé coaxialement sur l'arbre principal (3), et
ayant une extrémité reliée au contacteur mobile (38) ;
un ressort de fermeture (25) pour fournir une énergie d'entraînement pour déplacer
le contacteur mobile (38) vers la position de fermeture ;
un levier d'entraînement (24) relié au ressort de fermeture (25), et mobile en rotation
sous l'effet de la force d'entraînement procurée par le ressort de fermeture (25)
;
une première liaison (29) configurée pour être mobile en rotation, et ayant une extrémité
reliée au levier d'entraînement (24) pour interverrouillage avec celui-ci ;
une seconde liaison (34) mobile en rotation par interverrouillage avec la première
liaison (29), ayant deux organes de plaque (34a, 34b), et ayant une paire de parties
en prolongement (55) dirigées vers la première liaison (29) de manière à empêcher
une interférence avec la première liaison (29) en maintenant une position interposée
de la première liaison (29) entre les deux organes de plaque (34a, 34b) ; et
une troisième liaison (35) ayant une extrémité reliée à la seconde liaison (34), ayant
l'autre extrémité reliée au levier d'arbre principal (40), et entraînée en rotation
ensemble avec la seconde liaison (34) de manière à déplacer le contacteur mobile (38)
vers la position de fermeture, pour faire tourner le levier d'arbre principal (40).
2. Liaisons à bascule d'un mécanisme de commutation (2) pour un coupe-circuit à air,
comprenant :
une première liaison (29) configurée pour être mobile en rotation ;
une seconde liaison (34) ayant une extrémité reliée à la première liaison (29), mobile
en rotation par libération d'une énergie élastique d'un ressort de fermeture (25),
et ayant une paire de parties en prolongement (55) s'étendant en direction de la première
liaison (29), de manière à empêcher une interférence avec la première liaison (29)
par maintien d'une position interposée de la première liaison (29) entre les deux
; et
une troisième liaison (35) ayant une extrémité reliée à la seconde liaison (34), et
entraînée en rotation ensemble avec la seconde liaison, pour déplacer le contacteur
mobile (38) vers la position de fermeture.
3. Les liaisons de bascule d'un mécanisme de commutation (2) pour un coupe-circuit à
air selon la revendication 2, dans lesquelles la première liaison (29) est un organe
de plaque, et la seconde liaison (34) comprend une paire d'organes de plaque disposés
de manière à être séparés l'un de l'autre d'une distance prédéterminée.