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Oct. 15, 1946.
2,409,575
R. l. MARKEY
BOMB RELEASING SHACKLE
Filed July 7, 11944
v3_-Sheets-Sheet 1
I
INVENTOR
Roscoe LMRRKEY,
ATTORNEY
Oct. 15, 1946. - I
2,409,575
R. |. MARKEY
BOMB RELEASING SHACKLE
Filed July 7, i944
sheetsésheet 2
m
INVENTOR
RoscOE LMARKEY,
BYg:
‘
IVATTORNEY
.'
2,409,575
Patented Got. 15, 1946
UNITED STATES PATENT OFFICE
2,409,575
BOMB RELEASING SHACKLE
Roscoe I. Markey, Montclair, N. 3., assignor to
Pollak Manufacturing Company, Arlington,
N. 5., a corporation of New Jersey
Application July 7, 1944, Serial No. 543,886
11 Claims. (01. 89-15)
1
2
The invention relates to bomb releasing
shackles and has to do more particularly with a
unit which carries the electrical mechanism for
operating the bomb holding or supporting means
of the shackle.
One of the objects of the invention is to pro
vide a simple compact and fool-proof unit for
Fig, 5 is fragmentary detail sectional plan view
taken on the line 5—5 of Fig. 4;
Fig. 6 is a cross sectional view on line 6—6 of
Fig. 4; and
Fig. '7 is a fragmentary elevational sectional
view taken in the same plane as Fig. 4 with the
parts in a different position, and taken on the
line 'i——? of Fig. 5.
attachment to a bomb shackle or rack, the unit
The present application relates to similar sub
containing all the electrical mechanism for op
erating the mechanical parts of the shackle or 10 ject matter to that disclosed in copending ap
plication, Serial No. 515,590, ?led December 24,
rack to release the bomb.
1943. In that application, as in the present one,
Another important object is to provide a unit
a removable control unit carrying all the electri
in which the operating or movable parts directly
cal operating means was disclosed. Said pending
motivated by the electrical operating means are
statically balanced thus resulting in ease of op 15 application and the present application have to
do with improvements disclosed in Patent No.
eration and the consumption of a minimum
2,344,211 dated March 14, 1944. Referring again
amount of current.
to the drawings, a shackle is shown similar to
Another object is to provide a unit in which
that‘ disclosed in the patent to Markey, No.
the parts are so arranged as to develop a mini
mum amount of friction during their actuation 20 2,298,360, dated September 22, 1942.
A framework or supporting structure It) has
and operation thus insuring more accurate func
hinge members ll resistance welded or otherwise
tioning, prolonging the life of the device and
secured to either end thereof. The upper parts
substantially decreasing the amount of current
of the hinge-members .support the shackle in its
Still another object is the provision of a unit 25 rack or hanger and hooks l2 are pivoted at l3
in the lower parts of the hinge-members. The
which is moisture proof and substantially air
hooks l? in the locked position of the shackle
tight thus guaranteeing the operation regardless
as shown in Fig. 1 close the entrances of open
of weather or atmospheric conditions.
Another object is the provision of improved 30 ings Hi and support rings or other suitable mem
bers l5 which carry the bomb (not shown),
simpli?ed means whereby the circuit to the toll
Theupper portions of the hooks l2 are piv
tale light in the bombardier’s station is broken
oted at it to a longitudinally extending tie mem
after a bomb has been dropped from its respec
ber ll. It will be apparent the hooks l2 and tie
tive shackle and at the same time a circuit is
member ll are movable simultaneously and fur
prepared, which when completed, will permit of
thermore the weight of the bomb as it is sus
a bomb being released from an adjourning sta
pended from the hooks will urge the tie member
tion.
and its hooks to bomb releasing position,
It will be understood that the foregoing gen
One of the hooks l2 has an extending toe l8
eral description and the following detailed de
which engages a notch [Sin a lever 20 when the
scription are exemplary and explanatory of the
parts are in the locked position of Fig. l. The
invention but are not restrictive thereof. In ad
lever 2% is pivoted at 25 and it will be obvious
dition to the foregoing other objects and advan
when this lever is moved to the right in Fig. 1,
tages will become apparent as this speci?cation
either manually or by electrically operated
proceeds. Referring to the drawings forming a
part thereof and in which one embodiment of the 45 means, the end ofthe toe l8 will move away from
the notch la and the bomb will be dropped.
invention is illustrated:
_
The control unit comprise a, box-like casing
Fig. 1 is an elevational view looking toward
25 having a cover 26 secured thereto by bolts 21.
the rear of the control unit and part of the
A gasket 28 is interposed between the walls of
shackle being indicated in broken lines;
the casing and the cover, the gasket functioning
Fig. 2 is a top plan view;
to insure the interior of the ‘casing being mois
Fig. 3 is an end view, the shaclde being in sec
ture proof and substantially airtight. The cas
tion;
ing houses the releasing magnet,'the mechanism
Fig. 4 is an elevational view of the control unit
needed, particularly for initial operation,
taken on a larger scale and with the cover re
moved;
operated thereby, the switches and wiring.
If
55 desired as in the aforesaid mentioned application,
3
2,409,576
vSerial No. 515,590, arming units may be mounted
4
magnet is designated by the reference numeral
on the bottom or exposed face of the casing.
54 and its core by the numeral 55.
The control unit may be detachably secured
Pivoted at 50 and 5'! are a pair of hell crankv
to the shackle in numerous ways, the particular
levers 58 and 59 both under the in?uence of
method illustrated forming no part of the pres in the electro-magnet. As illustrated the bell crankl
ent invention. As shown a shouldered pin 30 is
levers are formed of laminations to provide a
mounted in an ear 3| depending from the lower
better path or circuit for the magnetic flux and
part of the casing. Secured to the inner end of
as particularly shown in Figs. 4 and 5 the lam
the pin 30 is an arm 32 which has a socket taking
inations are secured together by peened over
over the protruding head of the pin 2| upon 10 pins 60.
which the lever 20 is pivoted. The pin 30 has a
The levers are arranged so they will function
knob 34 on its outer end and a spring 35 engages
in absolute unison with each other or to all in
this knob to urge the pin 30 and its arm 32 to
tents and purposes as a single unit and yet have
holding position. When it is desired to remove
a toggle like action with the practical elimination
the control unit from the shackle the knob 34
of friction. Thevinner adjacent ends of the hori
is depressed to cause the socket in the arm to be
zontal arms 62 of the bell crank levers are bi
come disengaged from the head of the pin 2| and
furcated or provided with semi-circular indenta
the arm is rotated to move it from the under side
' tions 63 which cooperate with a headed stud 54.
of the shackle frame.
The head 65 of the stud 64 is loosely con?ned be
To properly position the control unit on the
tween the ends of the levers and a spacer plate 56
shackle in relation to the lever 20 a projecting
-which rests against the inside of the cover 25.
end of pin 2| engages a recessed screw head
Thus what might be termed a ?oating anti-fric
35 which is preferably formed on one of the
tional pivotal connection is formed between the
screws 1 utilized to secure the cover 26 in place.
adjacent ends of the arms 62 of the bell crank
To further insure against any upward displace
levers. In addition this arrangement of levers
ment or canting of the control unit a ?xed stud
provides for a means of positively connecting
31 carried by another ear 38 depending from
magnetic forces in a linkage to release the pawl
the casing engages the lower edge of one of the
25.
'
shackle side plates.
One of the important aspects of the present
To complete the detachable securing means a
invention is the fact that the two levers 58 and
spring clip 39 is secured to the cover or rear of
59 when connected by the stud 64 are statically
the control unit at the upper part thereof and
balanced in relation to each other, and in rela
the spring clip has a pair of ?ngers 40 extending
tion to their pivots or in other words when they
over, and gripping the rear plate of the shackle
are in their normal position or the full line posi
frame and another ?nger 4| which rests upon 35 tion of Fig. 4 they are in a state of equilibrium.
or engages the connecting portion of the shackle
Thus when the magnet is energized and the levers
frame plates.
are attracted there is positively no gravitational
A cable 42 carries all of the electrical connec
weight to overcome. Therefore the magnet may
tions into the control unit. In order to obviate
be comparatively quite small and light weight
confusion in the drawing the various electrical 40 in construction in consideration of the work to be
connections 43 are broken away immediately
accomplished, that is releasing the mechanism
upon their entrance into the casing as shown in
to drop a bomb of 1000 pounds or more. An
Fig‘. 4. It is to be understood they will lead to
other bene?cial advantage of the statically bal
the magnet and various switches, hereinafter de
anced levers is that a minimum amount of cur
scribed, in the conventional manner. As the elec 45 rent is needed to energize the magnet and at
trical circuits are substantially the same as illus
tract the levers and in addition the mechanism
trated in the wiring diagram of my aforesaid men
functions to prevent external forces from acci
tioned pending application, Serial No. 515,590,
dentally releasing the bomb. The studs 55 and
reference may be had to said diagram.
51 upon which the levers are pivoted are ad
A clip 44 is secured to the cable just outside of 50 vantageously mounted in bosses 6| formed on
the casing and a bracket 45 welded or otherwise
the, bottom wall of the casing as shown in Fig. 5.
fast to the clip is secured at 46 to the casing.
The spacer plate 66 has a pair of cup-shaped
This arrangement relieves strains on the cable and
portions 61 found on either end thereof and
insures against the withdrawal of the cable from
provided with apertures into which the pivotal
the casing when the control unit'or the control 55 studs 56 and 5'! are entered. The bell crank
unit and the shackle may be carried by the cable
levers are loosely con?ned between the bosses 6|
alone, such for instance as when the supply of
and the portions 61 thus providing for free pivots
bombs is being replenished. The cable leads to
and preventing endwise displacement of the levers
a conventional disconnect plug ,(not shown)
in relation to the studs. The spacer plate 66
which if desired might be secured to the casing 25. 60 thus serves a dual purpose, that is maintaining
It will be apparent that a control unit is thus
the headed stud 64 in position as well as the levers
provided which may be instantly attached to
58 ‘and 59,rno screw threads or nuts being re
or detached from the shackle. When the shackle
quired to form the pivots.
is removed from the control unit to apply it to
The bell crank levers 58 and 59 have vertically
another bomb the control unit remains suspended 65 or upwardly extending arms 68 and 69 which
from the cable 42. Obviously the cable connect
function as armatures for the electro-magnet. A
ing means might be widely varied.
laterally extending toe 10 formed on one of the
The full line position of Fig. 14 illustrates the
laminations of the lever 59_carries a pin 'H which
parts of the control unit for operating the bomb
may be provided with an anti-friction roller if
releasing mechanism in the position they would 70 desired, and this pin functions to operate the
assume when the shackle mechanism is in bomb
switches hereinafter described.
supporting position. An electro-magnet 50 is car
The upper portion of the arm 69 is bifurcated
ried in the casing 25 by a pair of brackets 5|
or in effect the two outside laminations project
secured by screws 52 to a boss 53 formed integral
upwardly and a pin 12 extends between them.
with. the casing. The winding of the electro 75 This pin 12 carries an anti-friction roller 13 for
2,409,575
engagement with a suitable notch 14 in a pawl
15, the purpose of which will be hereinafter de
scribed.
A spring ‘It normally urges the arm 69 away
from the core of the magnet 58, and the pin 12
and its roller into engagement with the notch
'14. As illustrated in Fig. 4 one end of the spring
rests over the upper part of the arm 69 and it
6
of Fig. 4 or the bomb holding position the con
tacts 92 and 93 are closed, the pilot light in the
bombardier’s station is on and» when a switch
in the circuit controlled by closed contacts 93 is
thrown the electro-magnet 50 is energized, the
parts assume the A position and the bomb is
dropped, the contacts 92 and 93 remaining closed.
When the current to the magnet 50 is cut the
bell crank levers 58 and 59 under the urge of
then passes downwardly under the pivots 55 and
57 of the bell crank levers. The arrangement of 10 the spring 16 will assume the B position of Fig.
4 or the full line position of Fig. 7. The con
the spring permits of a minimum amount of
tacts 92 and 93 will be opened, the light in the
energy being expended in moving the bell crank
bombardier’s station going out to inform him the
levers from the full line locked position of Fig. 4
bomb has been released and the one in the next
to the broken line position A which the bell
crank levers occupy when the magnet is ener 15 station is ready, and the circuit has been broken
to the ?rst station. The contacts 94 are closed
gized and the bomb is to be released, thus en
Apart from the two outside laminations
to prepare the circuit for the electro-magnet in
the next station so that when the main switch is
84 may be provided'in the bushing for weather
engages its seats 63 in the adjacent ends of the
tailing the use of a minimum amount of cur
rent.
closed again the cycle will be repeated. The broad
of the arm 59 the remaining laminations are
slabbed oilr as indicated at TI to provide a clean 20 aspects of this system being well known it is not
thought necessary to show a wiring diagram, and
ance for the pawl 15 as will be hereinafter ap
if desired reference may be had to my copending'
parent.
application, Serial No. 515,590, ?led Dec. 24, 1943.
The pawl ‘i5 is pivoted to one of the cover
To facilitate moving the parts back to the bomb
retaining studs 21. As heretofore stated when
the parts are in the full line position of Fig. 4 25 holding position the upper surface of the pawl i5
or the bomb supporting position the notch 711 on
is curved at its free end as indicated at 56. This
the free end of the pawl is in engagement with
curved portion cams against the roller 13 until
the pin and roller 12, 13 on the upper end of
the roller slips over the end of the pawl and enters
the arm 69 of the bell crank lever 59. A link or
its notch 14.
a pair of links 18 is pivoted at one end '19 to
Fig. 7 illustrates the posiiton of the parts after
an intermediate position of the pawl and at the
the bomb has been dropped and the current has
other end 80 to a block 8 I.
been cut to the magnet 56. It will be noted when
The block BI is formed as part of a plunger
the arms 62 of the bell crank levers are in the
32 which has a bearing at one end in a bushing
8-3 mounted in the casing 25. A felt packing 35 horizontal position of Fig. 4 the stud 64 snugly
lever arms. Both arms will thus be kept in line
proo?ng purposes. The end of the plunger ex
with a minimum amount of friction being ex
tending beyond the casing 25 carries an arm 85
erted. When the levers are moved to the posi
having a toe 86 which engages the operating le
40 tion of Fig. 7 or in the reverse direction as would
ver 2% of the bomb releasing mechanism.
be the case when the magnet is energized the
The part of the plunger extending on the 0p
stud moves slightly away from its sockets or seats
posite side of the block 81 is surrounded by a
63 and thus while maintaining to all intents and
spring 81 which is confined between the block 8!
purposes a rigid connection between the arms for
and the end wall of the casing 25 whereit takes over
a positioning abutment 88. The spring 87 is sur 45 the lines of magnetic ?ux and for up or down
movement of the arms, it positively removes the
rounded by a tube 89 which acts as a guide for a
increment of friction.
spring 90 of larger diameter and which is like
Obviously the release control may be used on
wise con?ned between the block 3! and the end
' racks as well as shackles or it may be used on a
wall of the casing. The two springs provide am
ple power to operate the bomb releasing’ mech 50 combination rack where a series would be mount
ed in the same structure. In other words the
anism through the medium of the lever 20. To
release control unit is extremely versatile and
provide for a further guide for the springs and
may be used in any bomb release mechanism where
the plunger the upper portions of the magnet
retaining brackets 5|, as shown in Fig. 6 are
appropriately shaped. The bracket 5| prevents
lateral displacement of the magnet '50 and lugs
9! formed on the bottom wall of the casing en
gage the ends of the magnet core to prevent lon
gitudinal displacement thereof.
a high speed release is desired to control the
55 energy stored in a spring by electric control.
From the foregoing it is thought to be appar
ent a release unit for a bomb shackle has been
provided which will function accurately and ef
?ciently, one that may be assembled with the
Referring again to the toe l9 and the pin H 60 greatest of ease and with practically no equip
ment outside of a screw driver, and one in which
for operating the switches it will be noted there
the parts are all readily accessible after the cover
are three sets of contacts 92, 93 and 94 separated
has been removed so that any of the parts may
by suitable insulation blocks 95 and as shown in
be quickly removed and replacements made.
Figs. 4 and 5 they are mounted as a unit which
Such changes in details of construction and
may be readily installed in or removed from the 65
casing.
'
arrangements of parts as would occur to one
skilled in the art are to be considered as coming
The contacts 92 might be termed normally
within the spirit of the invention as set forth in
closed contacts and their leads (not shown) con
the appended claims.
trol the pilot light in the bombardier’s station.
I claim:
‘
The contacts 93 are likewise normally closed con 70
l. A control unit for housing the electrical
tacts and control the circuit to the magnet 59.
mechanism for operating a bomb releasing
The contacts 94 are normally open contacts and
shackle, said control unit having in combination,
control the circuit leading to the magnet ‘in the
a casing, an electro-magnet mounted in said cas»,
next .or adjoining station.
When .the parts-:are ‘in: the full line position‘ 751 ing,>a~pair of statically balanced'bell crank levers
2,409,575
7
pivoted in said casing, one of the arms of each of
the bomb ‘holding position; and means releasable
said statically balanced levers functioning as ar
by said pawl for releasing the ‘bomb holding
matures for said electro-magnet means between
mechanism of said shackle when said magnet is
the other arms of said statically balanced levers
energized.
for causing them to move in unison with each
6. A control unit for housing the electrical
other, and means releasable by one of said arms
mechanism for operating a bomb releasing
of one of said statically balanced levers for releas~
shackle, said control unit having in combination,
ing the bomb holding mechanism of said shackle
a casing, an electro-magnet mounted in said
when said magnet is energized,
casing, a pair of statically balanced bell crank
2. A control unit for housing. the electrical 10 levers pivoted in said casing, one of the arms of
mechanism for operating a bomb releasing
each of said statically balanced levers functioning
shackle, said control unit having in combination,
as armatures for said electro~magnet, means in
a casing, an electro-magnet mounted in said cas
terposed between the adjacent ends of the other
ing, a pair of statically balanced bell crank levers
arms of said statically balanced levers to cause
pivoted in said casing, one of the arms ofeach 15 said levers to move in unison with each other,
of said statically balanced levers functioning as
spring means urging said armatures away from
armatures for said electro-magnet, means inter
said magnet, a pawl having its free end engaging
posed between the adjacent ends of the other arms
one of said armatures when the parts are in the
of said statically balanced levers to cause said
bomb holding position, a rod slidably mounted in
levers to move in unison with each other, and 20 said casing, links connecting said pawl and said
means releasable by one of the ?rst mentioned
rod, and means operable by said rod for releasing
arms of one of said statically balanced levers for
the bomb holding mechanism of said shackle when
releasing the bomb holding mechanism of said
said magnet is energized.
shackle when said magnet is energized.
7. A control unit for housing the electrical
3. A control unit for housing the electrical 25 mechanism for operating a bomb releasing
mechanism for operating a bomb releasing
shackle, said control unit having in combination,
shackle, said control unit having in combination,
a casing, an electro-magnet mounted in said cas
a casing, an electro-magnet mounted in said cas
ing, a pair of statically balanced bell crank levers
ing, a pair of statically balanced bell crank levers
pivoted in said casing, one of the arms of each of
pivoted in said casing, one of the arms of each
said statically balanced levers functioning as an
of said statically balanced levers functioning as
armature for said electro-magnet, means inter
armatures for said electro-magnet seats formed
posed between the adjacent ends of the other
in the adjacent ends of the other arms of said
arms of said statically balanced levers to cause
statically balanced levers, a stud cooperating with
said levers to move in unison with each other, a
said seats to cause said levers to move in unison
pair of normally closed switches and a normally
with each other and means releasable by one of
open switch mounted in said casing, means car
the ?rst mentioned arms of one of said statically
ried by one of said statically balanced levers for
balanced levers for releasing the bomb holding
opening said normally closed switches and clos
mechanism of said shackle when said magnet is
ing said normally open switch, and means releas
energized.
able by one of the ?rst mentioned arms of one
4. A control unit for housing the electrical
of said statically balanced levers for releasing the
mechanism for operating a bomb releasing
bomb holding mechanism of said shackle when
shackle, said control unit having in combination,
said magnet is energized.
a casing, an electro-magnet mounted in said
8. A control unit for housing the electrical
casing, a pair of statically balanced bell crank
mechanism for operating a bomb releasing
levers pivoted in said casing, one of the arms of
shackle, said control unit having in combination,
each of said statically balanced levers functioning
a casing, an electro-magnet mounted in said cas
as armatures for said electro-magnet seats formed
ing, a pair of statically balanced bell crank levers
in the adjacent ends of the other arms of said
pivoted in said casing, one of the arms of each of
statically balanced levers, a stud cooperating with
said statically balanced levers functioning as ar
said seats to cause said levers to move in unison
matures for said electro-magnet, means inter
with each other, a spacer plate carried by the
posed between the adjacent ends of the other
pivots of said statically balanced levers, said
arms of said statically balanced levers to cause
spacer plate functioning to aid in preventing dis
said levers to move in unison with each other, a
placement of said levers, a, head on said stud. said
pair of normally closed switches and a normally
head being con?ned between said levers and said
open switch mounted in said casing, a toe formed
spacer plate, and means releasable by one of the
on one of said statically balanced levers, a pin
?rst mentioned arms of one of said statically
carried by said toe for opening said normally
balanced levers for releasing the bomb holding
closed switches and closing said normally open
mechanism of said shackle when said magnet is 60 switch, and means releasable by one of the ?rst
energized.
.
mentioned arms of one of said statically balanced
5. A ‘control unit for housing the electrical
levers for releasing the bomb holding mechanism
mechanism, for operating a bomb releasing
of said shackle when said magnet is energized.
shackle, said control unit having in combination,
9. A control unit for housing the electrical
a casing, an electro-magnet mounted in said
mechanism for operating a bomb releasing
casing, a pair of statically balanced bell crank
shackle, said control unit having in combination,
levers pivoted in said casing, one of the arms of
a casing, an electro-magnet mounted in said cas
each of said statically balanced levers functioning
ing, a pair of statically balanced bell crank levers
as armatures for said electro-magnet, means
pivoted in said casing, one of the arms of each
interposed between the adjacent ends of the other
of said statically balanced levers functioning as
arms of said statically balanced levers to cause
armatures for said electro-magnet, means inter~
said levers to move in unison with each other,
posed between the adjacent ends of the other
spring means urging said armatures away from >
arms of said statically balanced levers to cause
said magnet, a pawl haVlng its free end engag
said levers to move in unison with each other, a‘
ing one of said armatures when the parts are ‘in 75 normally closed switch for controlling a circuit
2,409,575
to a pilot light, a normally closed switch for con
10>
magnet is energized said arm under the in?uence‘
trolling a circuit to the electro-magnet, 3, nor
of said spring means will move said control lever
mally open switch for controlling a circuit lead
ing to an electro—1nagnet of the shackle at the
next station, all of said switches being mounted
to operate said bomb releasing means.
11. A bomb releasing shackle having in com
bination a frame provided with supporting and
releasing means for a bomb, a control lever for
operating said releasing means, a control unit
comprising a casing mounted on said frame adja
cent said control lever, a magnet mounted in said
open when the levers are in bomb holding posi~ 10 casing, an arm extending from said control unit,
said arm engaging said control lever, a pair of
tion and when the magnet is energized to bring
statically balanced levers pivoted in said casing
said levers to bomb releasing position, and the
and under the influence of said magnet, a nor
normally closed switches being opened and the
mally closed switch for controlling a circuit to a
normally open switch being closed when the cur
pilot light, a normally closed switch for control
rent to the magnet is cut, and means releasable
ling a circuit to the electro-magnet, a normally
by one of said ?rst mentioned arms of one of said
open switch for controlling a circuit leading ‘to
statically balanced levers for releasing the bomb
an electro-magnet of the shackle at the next sta
holding mechanism of said shackle when said
tion, all or" said switches being mounted as a unit
magnet is energized.
in said casing, a pin carried by one of said
10. A bomb releasing shackle having in combi
statically balanced levers to operate said switches,
nation a frame provided with supporting and re
the normally closed switches remaining closed and
leasing means for a bomb, a control lever for
the normally open switch remaining open when
operating said releasing means, a control unit
the levers are in bomb holding position and when
comprising a casing mounted on said frame ad
the magnet is energized to bring said levers to
jacent said control lever, a magnet mounted in
bomb releasing position, and normally the closed
said casing, an arm extending from said control
switches being opened and the normally open
unit, said arm engaging said control lever, a
switch being closed when the current to the mag
pair of statically balanced levers pivoted in said
net is cut, and connections between said statically
casing and under the influence of said magnet, a
pair of normally closed switches and a normally - balanced levers and said arm spring means
whereby when said magnet is energized said arm
open switch mounted in said casing means car
under the in?uence of said spring means will
ried by one of said statically balanced levers for
move said control lever to operate said bomb re
opening said normally closed switches and clos
as .a unit in said casing, a pin carried by one of
said statically balanced levers to operate said
switches, the normally closed switches remaining
closed and the normally open switch remaining
leasing means.
ing said normally open switch, and connections
including spring means between said statically 35
balanced levers and said arm whereby when said
ROSCOE I. MARKEY.
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