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Патент USA US3084248

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April 2, 1963
R. J. BASKERVILLE
3,084,238
RATCHET MECHANISM/FOR CHARGING A CLOSING SPRING
IN AN, ELECTRIC CIRCUIT BREAKER
Filed Nov. 3. 1960
3 Sheets-Sheet 1
Inventor:
Ralph J. Baskerville,
b5 QUMYS. Atto'r'ne .
April 2, 1963
R. J. BASKERVILLE
3,084,238
RATCHET MECHANISM FOR CHARGING A CLOSING SPRING
IN AN ELECTRIC CIRCUIT BREAKER
Filed Nov. 3, 1960
5 Sheets-Sheet 2
Inventor‘:
Ralph J. Baskerville,
b5 aQQN-ck S.
Attorney.
April 2, 1963
R- J. BASKERVILLE
3,084,238
RATCHET MECHANISM FOR CHARGING A CLOSING SPRING
Filed Nov. 3. 1960
IN AN ELECTRIC CIRCUIT BREAKER
-
3 Sheets-Sheet 3
uh.
Inventor:
Ralph J.Baske1~vil|e,
b5 Ms.Attorney.
W
"i
3,084,238
Patented Apr. 2, 1963
2
FIG. 1 is a side elevation of a circuit breaker equipped
with a stored energy closing mechanism and a manually
3,084,238
RATCHET MEtIHANlSM FOR CHARGENG A
CLOSING SPRING IN AN ELECTRIC ClRCUlT
BREAKER
Ralph J. Baskerville, Drexel Hill, Pm, assignor to General
Electric Qompany, a corporation of New York
Filed Nov. 3, 1960, Ser. No. 67,087
5 Claims. (C1. 2011-153)
operable charging means for the closing mechanism, the
charging means ‘being constructed in accordance with
the improvements of my invention;
FIGS. 2, 3 and 4 are a series of enlarged and exploded
front views of the charging means of FIG. 1 showing,
respectively, the ratchet wheel of the charging means in
three di?erent positions corresponding to early steps in
This invention relates to an improved ratchet mech 10 the charging operation; and,
FIG. 5 is a partially exploded front view of a ratchet
anism vfor manually charging a closing spring in an
wheel of modi?ed construction.
electric circuit breaker.
Referring now to FIG. 1, the schematically illustrated
In a copending patent application S.N. 63,802, Baird,
electric circuit breaker is seen to include a pair of separable
?led on October 20, 1960, and assigned to the assignee
of the instant application, there is disclosed and claimed 15 switch contacts 11 and 12 connected in a circuit 13 in
order to open and close that circuit. One switch contact
a double-pawl ratchet mechanism for charging a closing
12 is carried by a movable switch arm 14 between an
spring in an electric circuit breaker. In accordance with
open circuit position, in which it is shown in FIG. 1,
that disclosure, the ratchet mechanism comprises a rotat
and a closed circuit position in which it is engaged by
able ratchet member connected to the closing spring to
stress the spring upon rotation of the member, and a pair 20 the other switch contact 11. The movable switch arm
14- is pivotally supported at 15 and is biased by a suitable
of reciprocating pawls are ‘disposed to rotate the member
opening spring 16 to an “open” position corresponding
upon operation thereof. The pawls are operated by a
to the open circuit position of the switch contact ‘12.
conveniently disposed oscillatory handle, and by pumping
For actuating the switch arm 14, and hence moving
the operating handle an operator can e?fect step-by~step
advancement [of the ratchet member thereby charging 25 the switch contact 12 to its closed circuit position, I have
shown in FIG. 1 a conventional trip-free operating mech
the closing spring. It is an object of my invention to
anism comprising a pair of toggle links 17 and .18 pivotally
provide certain improved features in the above-described
joined together at a knee 19‘. One toggle link 17 is
ratchet mechanism.
pivotally connected to the movable switch arm 14, where
A more speci?c object of the present invention is the
as the other toggle link 18 is connected by pivot pin 20
provision, in a ratchet mechanism for charging the closing
to the upper end of a guide link 21. The guide link 21
spring of an electric circuit breaker, of improved means
is pivotally supported at its lower end by a ?xed iulcrum
for interconnecting the rotatable ratchet member and the
2.2. The pivot pin 2t} carries a latch roller 23 which co
closing spring without the necessity of relatively complex
operates with a suitable trip latch 24.
and expensive linkages.
So long as the trip latch 24 remains in the latched
Another object of this invention is to provide an im 35
position shown, the toggle 17, 18 is capable of transmitting
proved, safer circuit breaker in which inadvertent move
thrust to the movable switch arm 14. Thus, when its
ment of an oscillatory operating handle, which is pro
knee 19 is lifted from the position shown in FIG. 1, the
vided ‘for manually closing the breaker contacts, is pre
toggle 17, 18 is extended thereby driving the switch con
vented.
tact 12 toward its closed circuit position. This lifting of
A general object of the invention is to provide an im
the toggle knee is accomplished by the action of a ro
proved ratchet mechanism structure of the character de
tatable cam 25 operatively coupled to a roller 26 which
scribed hereinafter.
is mounted on the knee 19. Preferably, the closing cam
In carrying out my invention in one form, the ratchet
mechanism is arranged to charge a circuit breaker clos 45 25 is arranged to ‘drive the toggle slightly overcenter and
against a stop 27 so that the switch contact 12 will be
ing spring having an arcuately movable spring retaining
held in closed circuit position even when the cam is
member associated therewith. The ratchet mechanism
returned to its original position shown in FIG. 1.
includes a rotatable ratchet wheel having an eccentric out
Should the latch 24 be tripped when the breaker is
put element orbitally movable in a plane which intersects
the plane of arcuate movement of the spring retaining 50 closed, or even during the closing operation, the toggle
17, 18 will be rendered inoperative to transmit thrust to
member. The output element and the spring retaining
the movable switch arm 14. As a result, the opening
member are interconnected by means including a bearing
spring 16 impels the switch contact 12 to its open circuit
having a spherical camm-ing surface, whereby the retain
position. As long as the latch 24 is held tripped, the
ing member is moved and the spring is stressed in re
In order to rotate the
toggle 17, 18 will remain inoperative to transmit closing
ratchet wheel, a pair of reciprocating pawls are disposed
to engage peripheral teeth formed in the wheel. The
thrust to the movable switch arm 14. The latch may be
sponse to rotation of the wheel.
pawls are pi-votally mounted on \dilferent eccentric por
tions of an operating member disposed for oscillatory
movement, whereby the pawls are alternately eifective to
advance the ratchet wheel in response to oscillations of
the operating member. A pair of disc-like guide members
tripped by any suitable means, as, for example, by ener
gizing the winding of the solenoid 28 illustrated in FIG. 1.
A suitable resetting spring 29‘ cooperates with the guide
link 21 to reset the mechanism to the latched position after
it has been tripped.
‘
In order to rotate the closing cam 25 so as to actuate
the switch arm 14 and drive the contact 12 to its closed
circuit position, a stored energy closing device is provided.
of the pawls engages said predetermined teeth. :1 provide 65 As is seen in FIG‘. 1, this device comprises a heavy com
pression spring 36* suitably supported at its upper end by a
bias means for the operating member arranged yieldably
pivotally mounted bracket 31. Each end of a pin 32 trans
to oppose movement of this member at either limit of
versely extending from opposite sides of the bracket 31
its‘ oscillations.
is disposed in a vertically elongated slot 33‘ located in a
My invention will be better understood and its various
objects and advantages will be more fully appreciated 70 rigid frame member 34 of the circuit breaker. The lower
are disposed on the ratchet wheel to de?ne with predeter
mined peripheral teeth an annular track in which one
from the ‘following description taken in conjunction with
the accompanying drawings in which:
end of the spring 311 is supported by an arcuately movable
spring retaining member 35', and a rod 36 extending
3,084,238
vertically through the spring 30 is a?ixed to the upper
portion of member 35. The spring retaining member 35 is
pinned at 37 to a crankarm 38 which in turn is keyed to
a rotatable load‘ operating shaft 39 suitably journaled in
the frame member 34 of the breaker. The previously
mentioned closing cam 25 is also keyed to shaft 39.
In FIG. 1 the. spring 30 is shown in a compressed state.
, In other words, the spring, as shown in FIG. 1, is fully
4
ported oscillatory member 61. The pawls and teeth are
so arranged that the ratchet wheel 40 is angularly advanced
in a counterclockwise direction as viewed in FIGS. 2-4.
The oscillatory operating member 61 comprises a hori~
zontally oriented shaft suitably journaled in the mounting
block 42 and terminated at its forward end, in front of the
circuit breaker escutcheon 62, by a conveniently accessible
.“pistol grip” handle '63. The handle 63, which moves in a
charged and breaker closing energy is stored therein.
plane substantially perpendicular to the plane of move
Upon release of the closing energy (which occurs in a 10 ment of the circuit breaker switch arm 14, is designed for
manner described hereinafter) the spring force drives the
manual operation between a ?rst or lowered position
spring retaining member 35 downwardly in an arcuate
(FIGS. 1, 2 and 4) and a second or raised position (FIG.
path thereby rotating the load operating shaft 39 in a
.3) located about 120 angular degrees in a counterclockwise
clockwise direction, as viewed in FIG. 1. This produces
direction from the ?rst position.
rotation of the closing cam 25 of the mechanism in a 15
In accordance with one feature of my invention, the
manner to actuate the switch arm 14, whereby a high
operating member 61 has associated therewith suitable
speed and forcible closing operation of the circuit breaker
bias means for urging this member in a counterclockwise
is obtained.
, In order to charge manually the closing spring 30 of
the stored-energy closing device, a'double-pawl ratchet
direction, as viewed from the front of the circuit breaker,
7 .when the handle 63 is in its raised position (FIG. 3) and
20 alternatively for urging the member 61 in a clockwise
mechanism is provided. The ratchet mechanism includes
‘direction when the handle 63 is in its lowered position
a rotatable ratchet member,‘ to be referred to hereinafter
(FIG. 2). Preferably the bias means comprises a com
as therratchet Wheel, and this member is identi?ed gener
pression spring 64 disposed between a stationary bracket
ally by the reference number 40 in the drawings. The
65 mounted on the breaker frame and a radially project
ratchet wheel is supported by a sleeve (‘bearing 41 or the 25 ing element 66 keyed to shaft 61. A rod-like spring guide
like'for 360 degrees rotation about its axis 4%.‘. The
67 is pinned at one end to the projection 66 and slides
sleeve bearing is housed in a stationary mounting block
freely at its other end in a cooperating slot located in
42 which, as is shown in FIG. 1, is secured to the front
the bracket 65. With this arrangement a toggle-action
of the circuit breaker frame member 34-. Projecting rear
bias is obtained, whereby the spring 64 is able yieldably
wardly from the ratchet wheel 40' is an eccentric output 30 to oppose counterclockwise movement of the operating
element 43 which is connected to the spring retaining
handle 63 away from its lowered position and also to
member 35 of the stored-energy closing device by means
oppose clockwise movement of the handle 63 away from
including a self-aligning bearing 44 having a spherical
its raised position. The purpose of this two-way bias
camming surface. The bearing 44 is attached to the out
will become apparent when the operation of the FIG. 5
put element 43 and is snugly disposed between a pair of 35 embodiment of the ratchet mechanism is described herein
spaced, horizontally oriented plates 45a and 45b of the
after.
spring retaining member 35.
'
The rear end of the operating handle shaft 61 is pro
, As is indicated most clearly by FIGS. 1 and 2, the out~
vided with two eccentric portions ‘68' and 69 disposed on
put element 43 moves orbitally, upon rotation of the
opposite sides of the shaft axis, and the pawls 59 and
ratchet wheel 40, in a plane which intersects at sub 40 ‘6t? of the ratchet mechanism are pivotally mounted on
stantially a right angle the plane of arcuate movement of
vthese eccentrics 68 and 69, respectively, without any
the spring retaining member 35. The spherical camming
intermediate linkages. As is clearly shown in FIGS. 2-4,
surface of bearing 44 in cooperation with the ?at surfaces
the eccentrics are so disposed on shaft .61 that counter
of plates 45a and 45b provide a low-friction joint particu
clockwise movement of the operating handle 63, while
larly well suited ‘for directly translating the orbital motion 4.5 ~carrying pawl 60 to the left and downward, will cause
of the output element 43 into arcuate motion of member
the pawl ‘59 to move to the right and upwardly thereby
35. This feature of my invention enables a direct con
partially rotating the ratchet wheel 40, whereas the re
nection to be made between the element 41 and the mem
.verse or clockwise movement of the operating handle 63,
ber 35 even though these two parts undergo curvilinear
while carrying pawl 59 to the left and downward, will
motion in non-parallel planes, and more complicated and 50 cause the pawl 60 to move to the right and upwardly
expensive interconnecting linkages are eliminated.
‘thereby further rotating the ratchet wheel 40. Thus the
The closing spring 30, acting through its associated
pawl 59 is moved to effect angular advancement of the
retaining member 35 and the eccentric output element 43
wheel 40 by alternate strokes of the operating handle
connected thereto, normally biases the ratchet wheel 40 to
(upstrokes), and the pawl 60 is moved to effect similar
a ?rst angular position in which it is shown in FIG. 2.
advancement of the wheel by intermediate strokes of the
Here the output element 43 is at the lowest point in its
handle (downstrokes).
orbit, and the spring 30 is in a relatively extended state.
Pawl 59 is biased into engagement with one set of
The spring will be stressed and closing energy is accumu
peripheral ratchet teeth (51, 53, 55 and 57) by means
lated therein upon rotation of the ratchet wheel 40 to, a
of an appropriate tension spring 71 connected thereto,
‘predetermined second or top dead-center position wherein
while pawl 60v is biased into engagement with the other
the output element 43, as is shown in FIG. 1, is at its
set of peripheral ratchet teeth (52,754, 56 and 58) by
means of another tension spring 72. The wheel-driving
For the purpose of rotating the ratchet wheel 40, a
end of pawl 60 is disposed in an annular track de?ned
plurality of peripheral teeth are formed therein. Prefer
by two spaced-apart disc-like guide members or plates
ably these teeth are arranged in two sets disposed in side 65 73 and 74 disposed at opposite sides of the associated
by-side relationship, each set comprising four teeth. In
set of peripheral teeth. The guide members 73‘ and 74
apogee.
’
V
.
.
‘FIGS. 2-4 the successive teeth of one set are identi?ed by
are each affixed to the ratchet wheel by appropriate means
‘the reference numbers 51, 53, 55 and 57, respectively,
such as rivets (not shown), and they serve to limit side
and the successive teeth of the other set are identi?ed
wise movement of pawl 60 so that this pawl will not slip
by the reference numbers 52, 54, 5'6 and ‘58, respectively. 70 off the periphery of the ratchet wheel 40' during opera
The peripheral teeth 51-58 are sequentially engaged for
effecting step-by-step advancement of the ratchet wheel
‘40 from its ?rst position (FIG. 2) to its second or top
tion of the mechanism.
7
Sidewise‘movement of pawl 59 is limited in a like man
ner by the guide member 73 in cooperation with the part
dead-center position (FIG. 1) by a pair of reciprocating
of the breaker frame disposed immediately in front of
pawls 59 and 60 operated alternately by a pivotally sup 75 the ratchet wheel. 1 Since the space between member 73
3,084,238
5
.
6
and the breaker frame is more than twice the width of
spouse tostep-by-step rotation of the ratchet wheel, is so
the pawl 59, suitable spacers, such as the illustrated rivets
75 and 76 with protruding heads, have been attached
to pawl 59. In this manner the pawl 59' is prevented
from slipping off the one set of peripheral teeth (51, 53,
55 and 57) which it engages during operation of the
ratchet mechanism.
It will be observed in FIGS. 2-4 that the peripheral
compensated by the mechanism construction that repeated
teeth 51-53 on the ratchet wheel 46 are not uniformly
oscillations of the operating handle 63- can be effected with
the application of a relatively uniform amount of force.
As a result of this “leveling” characteristic of the ratchet
mechanism, the breaker closing mechanism can be manu
ally charged with relative ease and dispatch by an oper
ator exerting only a reasonable amount of force to etfect
each stroke of the handle 63.
Preferably the relatively-uniform-manual-force operat
spaced from the axis 40a of wheel rotation. By dispos 10
ing characteristic of the ratchet mechanism is obtained by
ing the teeth at a plurality of different predetermined dis
appropriately selecting the different predetermined dis
tances from the axis of rotation, as shown in the drawings,
tances at which the various peripheral teeth 51-58 are
a special ratchet mechanism operating characteristic is
respectively spaced from the axis of the ratchet wheel 40.
realized. This special operating characteristic and the
The pawls 5‘9 and 60 which sequentially engage the pe
illustrated manner in which it is obtained will now be
ripheral teeth are thus given variable lever arms, with
explained in detail.
It will be apparent to those skilled in the art that the
respect to axis 4tla, andl'the mechanical advantage of the
'force required to stress the closing spring 30 of the circuit
pawl-and-tooth driving means for the ratchet wheel 40‘ is
breaker during a spring charging operation increases
changed in accordance with the angular position of the
wheel. In practice, the peripheral teeth can best be lo
pression. In other words, the force exerted by the spring
cated on the ratchet wheel by graphical methods within
30 on the spring retaining member 35, which member
the mechanical skill of the art, it being understood that
is lifted from its lowest position (FIG. 2) in order to
ideally the lever arms of the pawls 59 and 60‘, as they
compress the spring, increases directly in proportion to
engage successive teeth 51-58, should vary in the same
the distance which the spring has been shortened or de 25 relationship to the angular position of the wheel as the
?ected. As has already been described, it is the orbital
spring-produced torque varies. As a result of this con
movement of the eccentric output element 43 of the ratchet
struction, variations in the manual force needed to effect
wheel 40 that lifts the spring retaining member 35 there
successive upstrokes and downstrokes of the operating
by charging the closing spring. Accordingly, it is ap
handle .63 during the charging operation are minor com
parent that during the charging operation the output ele 30 pared to the relative increase in the force being exerted
ment 43 experiences a downwardly directed force which
by the closing spring 30. .
increases substantially linearly in accordance with its
Additional ease of operation of the manually operable
vertical displacement, that is in accordance with the ver
vratchet mechanism has been realized by so designing the
tical component of movement of element 43 as measured
mechanism that less force is required to effect an upstroke
from its initial position shown in FIG. 2. This relation
of the operating handle 63‘ than is required to effect the
ship can also ‘be expressed in'terms of the angular ad
preceding downstroke. This desirable result is obtainable
vancement of the ratchet wheel 40': the spring force which
in the illustrated mechanism by appropriately selecting the
bears on the element 43 is a constant-minus-cosine func
spacings, from axis 461:, of the ratchet teeth 53, 55 and 57
tion of the angular position of the ratchet wheel measured
in relation to the teeth 52, 54 and 56, respectively.
40
with respect to its initial or ?rst position (FIG. 2).
From the foregoing detailed description of the structure
The downwardly directed force acting on the spherical
and arrangement of] the illustrated ratchet mechanism, its
bearing 44 of element 43 during the spring charging op
mode of operation may now be readily followed. In
eration produces a torque in the ratch wheel 40 opposing
FIG. 2 the mechanism is shown in its initial position with
its counterclockwise advancement. The magnitude of this
the closing spring 30' discharged, and the operating handle
torque is, of course, the product of the magnitude of the
63 is in a vertical position as shown. An operator per
force and the length of its moment arm. The line of ac
forms the ?rst step of the spring charging operation ‘by
tion of the spring force on element 43 is nearly vertical,
twisting the handle 63 in a counterclockwise direction
as viewed in the drawings, and its moment arm is equal
through 120 degrees to its raised position. This upstroke
to the horizontal displacement of the element 43 with
of the operating handle causes pawl 59 to push against
respect to the vertical reference line 77 shown in FIG. 2. 50 peripheral tooth 5-1 thereby driving the ratchet wheel 40'
Thus, the moment arm of the spring force applied to the
in a counterclockwise direction through an angle of about
element ‘43 is a sine function of the angular position of
thirty degrees to the position in which it is shown in
the ratchet wheel 40. The spring-produced torque, which
FIG. 3. The resulting movement of the eccentric output
linearly in accordance with the amount of spring C0111
is opposing counterclockwise rotation of the ratchet wheel
element 43 lifts the spring retaining member 35 to begin
during the charging operation, is consequently a complex 55 the compression of the closing spring 30*.
function of the angular advancement of the wheel 40, the
The second step in the spring charging operation is
maximum spring-produced torque being realized when
performed by returning the operating handle 63‘ to its ini
the wheel has been rotated from its initial position to an
tial vertical position. This downstroke causes the oper
ating shaft 61 to rotate in a clockwise direction, and pawl
Rotation of the ratchet wheel 40, for the purpose of 60 69‘ coacting with the peripheral tooth 52 drives the ratchet
charging the breaker closing mechanism, is accomplished
wheel 40‘ further in the counterclockwise direction to the
by manual operation of the oscillatory handle 63.
position in which it is shown in FIG. 4. At the same
Through the action of the reciprocating pawls 59 and 60
time the pawl 59 is pulled into a position in which it en
in cooperation with the eight peripheral teeth 51-58, the
gages the next peripheral tooth 53. The closing spring
angular position approximately 120 degrees therefrom.
operation of handle 63 produces su?icient counterclock 65 30 is further compressed as a result of the upward move
ment of the output element 43 during the second step of
produced torque discussed above, whereby the closing
the operation.
To perform the third step of the spring charging oper
spring 30 is compressed and breaker closing energy is
ation, the operating handle 63 is again twisted in a coun
stored therein. Although the driving torque required to
terclockwise direction to its raised position, whereby pawl
rotate the ratchet wheel varies as the wheel advances, for
59, acting this time on through peripheral tooth 53, propels
reasons just explained, the ratchet mechanism is designed
wise driving torque in wheel 40 to overcome the spring
so that the force needed to operate the handle 63 does not
the ratchet wheel 40' through an additional counterclock
wise angle and the spring is further compressed. This
action is accompanied by the resetting of pawl 60 into en
More speci?cally, the increasing force characteristic of
the closing spring 30, as it is incrementally stressed in re 75 gagement with the next peripheral tooth 54. Upon re
correspondingly vary during the charging operation.
,
.
.
3,084,238
7
8
,
turning the operating handle to its initial position during
the fourth step of the operation, the pawl 60, acting
through tooth 54, drives the wheel further in the counter
clockwise direction, and still more energy is stored in the
closingspring.
_
The ?fth and sixth steps of the spring charging opera
tion‘are accomplished by again oscillating the operating
handle‘63, whereupon ?rst the pawl 59 in cooperation
wise movement of the ratchet wheel 40, which movement
follows overtravel of the wheel at the conclusion of a
breaker closing operation, when the wheel has attained
its initial position. This protects pawl 59 and the ?rst
5 peripheral tooth 51 from damage which might occur if
the abrupt interengagement of these members were used
to stop such clockwise movement of the ratchet wheel.
A portion ‘82 of the edge of the guide member 74 is so
relieved that the blocking ?nger 78 is’ held out of the
orbital path' of element 43 until after the leading edge
of this element has passed beyond the distal end of the
with perpiheral tooth 55, and then the pawl 60 in coop
eration with peripheral tooth 56, operate to further ad
Vance the ratchet wheel 40 and incrementally stress the
closing spring. The seventh step of the charging opera
?nger during the breaker closing operation, and in this
tion is an upstroke of the operating handle 63 which re
manner the possibility of misoperation of the blocking
sults in the operation of pawl 59, in cooperation with pe
means caused by rebounding thereof has been minimized.
ripheral tooth 57, to drive the ratchet wheel 40 further 15
In FIG. 5 a modi?ed construction of the‘ratchet wheel
in the counterclockwise direction.‘ The closing spring 30
40 is illustrated. The FIG. 5 ratchet 'wheel diliers from
is now almost tlully charged.
the ratchet wheel shown in FIGS. 2-4 in that an addi~
The eighth and ?nal step in the spring charging opera
tional six peripheral teeth 83-88 have been formed there
tion is a downstroke of the operating handle 63. Pawl
in. Three of these additional teeth 83, 8S and 87 are
60 is now in driving engagement with peripheral tooth 20 grouped with the odd-numbered set of peripheral teeth
58, and during this ?nal stroke (but before its conclusion)
51, 53, ‘55 and 57 for engagement by pawl 59, while the
the ratchet Wheel is advanced to a position 180 degrees
other three additional teeth 84, 86 and 88 are grouped
,from its initial position, this position being the top dead
with the even-numbered set of teeth 52, 54, 56 and 58
center position of the ratchet wheel. ‘ The closing spring
for engagement by pawl 60. These extra ratchet teeth
30 is now fully charged.
25 enable the circuit breaker to be slowly closed in order
The illustrated mechanism is designed so that the
to check the contact “wipe” adjustment or to facilitate
ratchet wheel is actually driven beyond its top dead-cen
ter position during the ?nal downstroke of the operating
?eld assembly of new switch contacts.
To utilize the above-mentioned slow-closing feature,
handle 63, and as a result the spring retaining member
the ratchet mechanism incorporating the FIG. 5 ratchet
35 is able to reverse its movement and the closing spring 30 wheel is operated by pumping the operating handle 63
30 is free to release the energy ‘which had been stored
in the manner described hereinbefore. However, near
during the charging operation. 'In other words, once the
the conclusion of a spring charging operation, and before
the ratchet wheel is driven beyond its top dead-center
ratchet wheel has been rotated by operation of the re—
'ciprocating pawls 59 and '60 in a counterclockwise direc
position, the operator must pause to insert a removable
tion beyond its top dead-center position, the output ele 35 pin (not shown) into a hole 89 located in the spring guide
ment 43- is no longer able to restrain downward move
rod 36 at its upper end. As can be seen in FIG. 1, at
ment of the spring retaining member 35. The release of
this point the spring ‘30 is so compressed that the hole
energy stored in spring 30 closes the circuit breaker
89 in rod 36 has become exposed above an integral plate
through the operation of the connected load operating
90 of the springs supporting bracket 31‘. The pin in~
shaft 39 and the breaker closing mechanism described '10 serted in hole 89 coacts with plate 9|) and rod 36 to in
hereinbefore, and at the same time the ratchet wheel 40
terconnect the upper bracket 31 and the lower spring re
taining member 35 in a manner which prevents elonga
is rotated further in a counterclockwise direction and re
turned to its ?rst or initial position shown in FIG. 2.
The ratchet wheel 40, which is driven from the top
dead-center position toward its ?rst position in response
to the release of closing spring energy, will experience
overtravel because of the inertia of the moving parts. In
other words, the ratchet wheel rotates in a counterclock
wise direction beyond its initial position (FIG. 2) at the
tion of the closing spring 30. Hence the spring will not
_ release any stored energy upon subsequent movement of
0
the ratchet wheel 40 beyond its ‘top dead-centerrposition.
The circuit breaker can now be slowly‘closed by con
tinued pumping of the manual operating handle 63.
In response to the next three oscillations of the operat
ing handle 63, the reciprocating pawls 59 and 60 sequen
conclusion of a breaker closing operation. This results 50 tially engage the additional ratchet teeth 83-88 thereby
in a clockwise torque being applied to the ratchet wheel
advancing the ratchet Wheel through approximately 180
by the closing spring 30 acting through the spring retain
degrees in a step-by-step manner. By this action the
ing member 35 and the eccentric output element 43, and
ratchet wheel is returned to its initial position, and its ec~
consequently the wheel 40 is driven backwards in a clock
centric output element '43- forces the spring retaining
wisedirection to its initial position. Again the inertia of 55 member 35 downwardly to its lowest position. As a re
the moving parts tends to cause overtravel, but such over
sult, the load operating shaft 39 and hence the closing
travel in the clockwise direction is prevented by blocking
cam 25 are rotated in a clockwise direction, as viewed
l means which will now be described.
The blocking means preferably comprises a ?nger-like
in FIG. 1, and the switch arm 14 is actuated by the cir
"cuit breaker ‘operating mechanism to carry the movable
member 78 pivotally mounted at 79 and biased by a 60 ~switch contact 12 ‘slowly to its closed circuit position.
spring 80 so that its distal end tends to move into the
orbital path of movement of the output element 43 of
'the ratchet wheel 40. The edge of the guide member 74-,
which is disposed adjacent to the blocking ?nger 78, is ~
During this operation the entire closing spring assembly
moves downwardly as a unit, with pin 32 of bracket 31
riding in the vertical slot 33‘ formed in the circuit breaker
frame member 34.
lslidably engaged by a lateral projection 81 of the ?nger as During a regular maintenance or inspection routine an
‘thereby to determine the position of the ?nger 78 as the
operator may stop the slow-closing operation before its
ratchet wheel rotates. This construction is shown in
conclusion, so as to inspect the partially closed switch
:FIGS. 2, 3 and 4. ‘It is apparent that the ?nger 78 is so
contacts or the like, and then reopen the breaker by de
inclined with respect to the orbital path of element 43
pressing a trip button (not shown) located on the breaker
that the ratchet wheel rotates without interference in a 70 vescutcheon 62. In the event that the operating handle
counterclockwise direction, While clockwise movement of
63 of the ratchet mechanism had been left in its raised
the wheel .from its initial'position (FIG. 2) will be
position when the slow-closing operation was stopped,
blocked by the abutting engagement between element 43
the bias spring 64 acting on shaft 61 will serve to hold
and thedistal end of the blocking ?nger '78.
‘the handle in this position and prevent its sudden return
The function of the blocking means 78 is to stop clock 75 to its lowered, normal position upon subsequent tripping
3,084,238
9
of the circuit breaker. This feature of my invention
prevents possible injury to the hand of the operator when
he depresses the trip button.
While I have shown and described a preferred form of
my invention by way of illustration, many modi?cations
will occur to those skilled in the art. I therefore contem
‘lb
of the pawls, whereby the wheel is advanced in a step
by-step manner by the alternate actions of said pawls
upon repeated oscillations of said handle.
. In an electric circuit breaker: a pair of separable
switch contacts; a movable switch arm disposed to move
one of the switch contacts from an open circuit position to
plate by the claims which conclude this speci?cation to
a closed circuit position; stored energy actuating means,
cover all such modi?cations as fall within the true spirit
and scope of my invention.
and a ratchet mechanism for charging the stored energy
including a spring, operatively coupled to the switch arm;
What I claim as new and desire to secure by United 10 actuating means, said ratchet mechanism including a
ratchet wheel for stressing said spring upon rotation there
‘States Letters Patent is:
of, ?rst and second reciprocating pawls each of which is
1. in an electric circuit breaker: a pair of separable
disposed to rotate the wheel upon operation thereof, an
switch contacts; a movable switch arm disposed to move
oscillatory operating handle for the pawls, said wheel
one of the switch contacts from an open circuit position
to a closed circuit position; stored energy actuating means 15 being partially rotated by the ?rst pawl in response to
movement of the handle from a ?rst position to a second
for the switch arm comprising a spring and an arcuately
movable spring retaining member associated therewith,
position and being further rotated by the second pawl in
said member being operatively coupled to the switch arm
response to the handle being returned from its second
spherical camming surface, whereby the spring retaining
ing a rotatable ratchet wheel operatively coupled to the
switch arm, ?rst and second reciprocating pawls each of
which is disposed to rotate the wheel upon operation
thereof, an oscillatory operating handle for the pawls,
position to its ?rst position, and means biasing the handle
for actuating the switch arm in response to release of
energy stored in the spring; and a ratchet mechanism for 20 to yieldably oppose movement of the handle away from
said ?rst and second positions.
charging the stored energy actuating means comprising a
4. In an electric circuit breaker: a pair of separable
rotatable ratchet wheel having an eccentric output ele
switch contacts; a movable switch arm disposed to move
ment orbitally movable in a plane which intersects the
one of the switch contacts from an open circuit position
plane of arcuate movement of the spring retaining mem
to a closed circuit position; and a ratchet mechanism for
ber, said output element being connected to said spring
actuating the switch arm, said ratchet mechanism includ
retaininsY member by means including a bearing having a
member is moved and energy is stored in the spring in
response to rotation of the wheel, said mechanism includ
ing at least one pawl for rotating the ratchet wheel and
an oscillatory operating member for the pawl.
2. In an electric circuit breaker: a pair of separable
switch contacts; a movable switch arm disposed to move
one of the switch contacts from an open circuit position
to a closed circuit position; stored energy actuating means, 35
including a spring, operatively coupled to the switch arm;
and means for charging the stored energy actuating means
comprising a rotatable ratchet wheel connected to said
said wheel being partially rotated by the ?rst pawl in
response to movement or" the handle from a ?rst position
to a second position and being further rotated by the
second pawl in response to the handle being returned from
its second position to its ?rst position, and bidirectionally
effective bias means connected to the handle to yieldably
oppose movement of the handle away from said ?rst and
second positions.
5. The electric circuit breaker of claim 4 in which the
spring to stress the spring upon rotation of the wheel, the
wheel having two sets of peripheral teeth disposed in 40 bidirectionally eifective bias means comprises a toggle
side-by-side relationship thereon, a pair of reciprocating
pawls disposed to engage the two sets of teeth, respec
tively, a pair of disc-like guide members on the wheel
disposed at opposite sides of one of the two sets of pe
ripheral teeth to de?ne therewith an annular track in 45
which the associated pawl engages said one set of teeth,
and an oscillatory handle operatively connected to both
action spring.
References Cited in the ?le of this patent
UNITED STATES PATENTS
2,644,053
2,965,737
Lingal et al. __________ __ June 30; 1953
Lewis et al. __________ __ Dec. 20, 1960
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