close

Вход

Забыли?

вход по аккаунту

?

Патент USA US3043943

код для вставки
July 10, 1962
w. J. WEINFURT
3,043,933
POLYPHASE CIRCUIT INTERRUPTERS
Filed Dec. 7, 1959
< -_
F] Ci 3
INVENTOR.
WlLLlAM J.W£|NFURT
BY
@47
ATTO2NEY
,.
United States Patent 0 " ICC
1
3,043,933
Patented July 10, 1962
2
latching and time delay arrangement shown may be ar
3,043,933
PQLYPHASE CIRCUIT INTERRUPTERS
William J. Weinfurt, Elm Grove, Wis., assignor to
McGraw-Edison Company, Milwaukee, Wis., a corpo
ration of Delaware
Filed Dec. 7, 1959, Ser. N0.‘857,661
3 Claims. (Cl. 200-97)
This invention relates to polyphase circuit interrupters.
Objects of this invention are to vastly simplify the con
struction of polyphase circuit interrupters and a primary
object of this invention is to provide hydraullic means
responsive to overloads in one or more of the phases for ’
ranged in any suitable manner and the one shown'is in
tended only to illustrate the principle of operation. As
an alternate to the Bourdon tube element, a small cylinder
with a movable piston as shown at 11 could be used.
At 9 is shown an expansion standpipe connected into the
manifold (or any point in the closed system). The lower
end of the standpipe is provided with a check valve nor
mally
close itbiased
rapidly.
openThe
butwhole
pressure
system
fromcomprising
the manifold
the bel~
lows, tubes, manifold, Bourdon tube and standpipe is com
pletely ?lled with hydraulic liquid.
The theory of operation is as follows: It is the purpose
simultaneously controlling all of the phases.
of this invention to operate the latch as nearly as possible
A speci?c object is to provide hydraulic means respon 15 as a function of pressure only. If the series coils acting
sive to overloads so that the timing for opening the cir
on the plunger cause the ‘bellows to generate a pressure
cuit interrupter is controlled by the largest overload in
which is a function of the current magnitude, then this
pressure will act against all elements of the closed hy
draulic system. If a current of lesser magnitude ?ows in
any one phase, independently of a lesser overload in any
other phase, and in which the effect of only one over
20 either or both of the other coils, their respective bel
load, viz the largest overload, determines the timing.
A ‘further primary object is to prevent the adding to
lows will attempt to generate a lesser pressure which will
gether of the e?ects of several overloads in different
phases, and to control the timing “as though only one
overload ‘was acting, as stated hereinabove.
A further primary object is operate the latch control
be ineffective since a greater pressure already exists in the
system. The net result of any pattern of currents in the
coils will be a pressure in the system which is directly
related to the highest current. It is understood that no
of a polyphase circuit interrupter as nearly as possible
appreciable displacement takes place in any of the
as a function of pressure only.
plungers to generate the pressure. When the pressure
attains a certain value, it will act on the Bourdon tube ele
ment of the pressure operated device which operates sub—
A further object is to provide means for improving
the operation and simplifying the construction of poly
phase circuit interlupters of the type shown in Patent .30 stantially solely as a pressure function to exert a force
Number 2,804,521, of August 27, 1957, of Van Ryan
on the free leg. This force acting on the time delay unit
and Date, assigned to the same assignee as the present
will take a de?nite time to complete the unlatching op
invention, in which it will not be necessary to use an in
eration, thus giving time to unlatch ‘as a function of cur
terrupted trip bar, as in such patent, but in which a con
rent magnitude.
It is obvious that it is impossible to
tinuous unbroken trip bar may be used, thus greatly 35 work a system on pressure alone since in order to do
simplifying the mechanical construction of the polyphase
some work on the latch pressure must be translated into
circuit interrupter.
a force acting through some distance. Therefore, some
displacement of ?uid is necessary. The success of the in
description proceeds.
dependent operation of the phase elements on a common
Referring to the drawing, in which a few of the many 40 time delay relies on the degree to which displacement
forms in which the invention could be used, it will be
can be limited. To attain this a latch system requiring
seen that:
very little work to operate should be employed, the piston
FIGURE 1 is a view of one form of the invention.
in 11 or the Bourdon tube volume should be small with
FIGURE 2 is a fragmentary view of a modi?cation
respect to the effective area of the bellows 2. The stand~
of the invention.
pipe is necessary to allow for thermal expansion in the
FIGURE 3 is a view showing how the invention could
closed system when no overcurrent exists. The check
be applied to polyphase circuit interrupters ‘as previous
valve 8 will take the standpipe out of the system when
ly constructed, and used to replace the complicated me
overcurrent pressures exist in the manifold.
chanical constructions.
'
Any suitable automatic or manual resetting means such
Referring to FIGURE 1, it will be seen that three 50 as 12 could be used.
identical phase units are shown as I, II, and III. Each
In FIGURE 3, it will be noted that the free end of the
is composed of a series coil surrounding a plunger or
Bourdon tube is connected to the trip bar 35 by a rigid
armature 1 which is held in ?xed position in the coil by
connecting member W.
its attachment to the bellows 2. The lower end of the
Although the invention has been described in consider
bellows is mounted ?xedly as shown. When an over-' 55 able detail, it is to be understood that such description
current ?ows in the coil, the plunger 1 is caused to exert
is intended as illustrative and not limiting, as the inven
a force on ‘the top of the bellows tending to collapse it.
tion is to be limited only as claimed.
The lower ‘end of each bellows is connected by an insu
I claim:
la-ting tube to a manifold 3‘ in such a manner that the
1. Means for controlling a polyphase circuit inter
bellows, tubing connections and manifold comprise a ?uid 60 rupter comprising a plurality of electromagnets, one for
tight vessel. 0n the right hand end of the manifold is
each phase, responsive to overload current, a hermetical
Other objects and improvements will appear ‘as the
a closed Bourdon tube type element shown as 4 which is '
ly closed hydraulic system including a hydraulic mani
a pressure operated device and operates substantially
solely as a pressure function. The free leg of the tube
fold, a hydraulic compressing means for each electro
rnagnet mechanically operated by the corresponding elec~
4 is linked to latch 5 by a link in such a manner that a 65 tromagnet and each being hydraulically connected to said
movement of the free end of 4 to the right will unlatch
manifold, a pressure operated device operating as a pres
_ the arm on operating shaft 6, allowing 6 to rotate clock
sure function hydraulically connected to said manifold,
wise since it is biased in this direction. This rotation
a polyphase circuit interrupter having a switch for each
of the operating shaft will open the main current carry
phase, and mechanism operatively connecting all of said
ing contacts (not shown). 7 is a time delay element so 70 switches with said pressure operated device for simul
arranged that it offers a de?nite resisting force tending
taneously opening all of said switches upon operation of
to retard the latch 5 in the unlatching movement. The
said pressure operated device.
8,043,938
3
2. Means for controlling a polyphase circuit inter
rupter comprising a plurality of electromagnets, one for
.
4
\fold, a hydraulic compressing means for each electro
magnet mechanically operated by the corresponding elec
each phase, responsive to overload current, a hermetical
tromagnet and each being hydraulically connected to said
ly closed hydraulic system including a hydraulic mani
fold, a hydraulic compressing means-for each electro
manifold, a pressure operated device operating as a pres
magnet mechanically operated by the corresponding elec
tromagnet and each being hydraulically connected to said
manifold, a pressure operated device operating as a pres
sure function hydraulically connected to said manifold,
a polyphase circuit interrupter having a switch for each
phase, and mechanism operatively connecting all of said
switches with said pressure operated device for simul
taneously opening all of said switches upon operation
sure function hydraulically connected to said manifold,
the volume of said pressure operated device being rela 10 of said pressure operated device, and reservoir means
connected ‘to said hydraulic system and having normally
tively small as compared with the volume of said hy
open check valve means arranged to close when said hy
draulic compressing means, a polyphase circuit inter
draulic compressing means operates.
rupter having a switch for each phase, and mechanism
operatively connecting all of said switches with said pres—
References Cited in the ?le of this patent
sure operated device for simultaneously opening all of
UNITED STATES PATENTS
said switches upon operation of said pressure operated
device.
2,392,282
Byerlay _______________ __ Jan. 1, 1946
3. Means for controlling a polyphase circuit inter
2,441,412
Haller _______________ __ May 11, 1948
rupter comprising a plurality of electromagnets, one for
2,765,378
Perry et al _____________ __ Oct. 2, 1956
20
each phase, responsive to overload current, a hermetical
2,920,607
Barkan ______________ __ Jan. 12, 1960
ly closed hydraulic system including a hydraulic mani
2,972,709
Chabala _____________ __ Feb. 21, 19611
Документ
Категория
Без категории
Просмотров
0
Размер файла
275 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа