Note: Descriptions are shown in the official language in which they were submitted.
(Ca~ No. 712~ J~
DUAL CONTROL R~IL~BL R ~ WAY SWITCII ~ACHINE
FIELD OF THE INVENTION
_ . ___ _
This invention relat2s to a railway switch machine hnd
more particularly to an irnprovec1 yard switch mechanism which
inc l~des a rev2rsi~1e electric rllotor for pow2r driving the
switch points to their extreme posikionsO and include~ a hand
throw lever :Eor manually shifting the switch points between
their extreme posi.t:ion and which includes a sprin~ toggle9 a
cxank, a main shaft~ a gear train and an electric clutch
which permit the switch point~ to be trailed hy the wheels
of a rai.lway vehicle without damage to the swi~ch mechani9mO
B~CKGROUND OF THE ~NVENTION
Generally, a railway switch machine which has universal
usage may be capable of having at least two alternate mode~
of functioning such as, power and manual o erations9 ~or
example, in classification yard operations, it is necessary
to provide both a power operating mode as well a~ manual
operating mode for mo~ing the swi~ch poink between their
normal and rever~e positions. That is9 in receiving and
dPparture yards as well as in mas~ transit yard~ and indus-
trial siding applications, the railway switches are used to
3et up th~ routes of tho cars or train~. I'he railway switches
are either automatically controlled from a remote location
by either a computer or a yard master, and therefore~ power
operation of the switch machines is required for such opera-
tionæO Likewise, in many instances, it is necessary to pro-
vlde a manual me! h~d GF manipl1lating tha railway switches.
For exam~le, du~ing certain ~ituations 3uch as, during power
:Eailura, malntenarlce periods or duriny Iraln pull out at the
departure yard~ ik is advantag00us to provida a manua:l. means~
such as~ a hand throw lever ~or m~ving the switch points be~
tweerl their kwo extreme positiorls~ In addi.tion, it is de~
sira~le in class.ification yard applicat:ions to provide trai.l-
able ~ype of swi~ch machines in order to prevent derailmsnts
of the railway vehicles and to preclude damage to the switchas
which could re~ult in prolong delays in shipping as well a~
cause costly damage to the equipment and/or ladingO Accord
ingly, in cla~slfication yards, a railway ~witch machine
must be capable of operating in three different fashions~
namely, power operation by a suitable operator, manual opera-
tion by the hand thxow lever and trailing operatlon by the
wheel~ of passing railway ve!hicles. While there have been
a number of pneumatic and electxic powered switch machines
which are capable of functioning in ~uch a manner~ each of
thase previous switch machines was pos~ess2d of certain in-
~erent disadvantages~ For example~ air laaks are a problem
with pneumatic switch machines and efficiency as w311 as
reliability is a shortcoming of previ.ous eleckric and
pneumatic switch machines~ Furthert previ.ous switch machines
were diffi.cult to maintaln and service. In addition~ moisture
and water accumulation within the housing resulted in power
failures and caused freeze ups during the winter and periodR
of cold weathe~r. Moreover, adjustment between the OUtpllt
member and the operating rod was either nonexistent cr
di:Eficult to achieve in previ.ous switch machi.nes~ Likewise,
prior switches were difficult to i.nstall and were not readily
adaptable Eor both xight-hand and le~t~hand application~.
O CTS OF THE NVENTIONS
Accordingly, it is an object of thi3 invention to pro-
vide a new and improved trailabl.e railway switch machine
which alleviates the above noted shortcomings.
Another object of this inve!ntion i~ to provide a unique
electric trailable switch machine which is modularly con-
structed for easy ma.intenance, repair and replacementO
A further object of this invention .is to provide a
novel trailable rallway switch machine in which the operating
rod ~tro~e may be ea~ily int~rna71y adjusted to provide proper
closure of the switch point~.
Yet another object of this invention i8 to provide a new
electric trailable dual control switch machine which includes
a water-tight welded housing for accommodating a ~pring
toggle, a main cxank~ a main shaft~ a motor-clutch transmi~;~
sion, a structural base, a cover, a hand throw lever, and the
electric control componentsO
Yet a further object of this invention is to provide an
improved low pro~ile dual control ~witch machine which may
be.mounted between two adjacent ties and which may be dis-
po~ed next to the runni.ng track railO
Still another object of thls invention i~ to provide a
new low-profil.e el~ctric trailable switch machine which is
adapted to be directly installed in either left hand or
.4~
right-hand applications without the need o:E ancillary equip-
ment~
Still a further objart of this invention is to provide
an ele~tric trailable switch machine for movirlg th~ ~witch
pol.nts between two extrPme posit:ion~ comprising, an electric
motor for power driving the swit:ch points between the two
extreme positions, the elactric motor i8 coupled to an
electric clutch which is energized and deenergi~ed in con-
cordance with the electric motox~ the elec~ric clutch i~
10 coupled to a gear train which pxovide~ a mechanical advantage,
the gear train i9 coupled to a ~pur gear which i~ mounted on
a main shaft~ the main shaft drive~ a pair of beveled gears
which cause angular di~placemont of an output crank, the
output crank i~ connected by an adju~table membax ~o an
15 operating rod whic~ i8 connectad to the swi~ch poin~s, and a
toggle mechanlsm is connect~d to the output crank for spring
biasing the switch points in either of th~ two extreme posi~
tions.
An additional object of this invention is to provide a
20 new and improved electric trailable dual control railway
~witch machine which i~ economical in co~t, efficient in
operationJ durable in ~ervice; reliable in use9 ea~y to
repair and maintain, facile to install and ~aEe to attending
per~onnelO
2 5 SUMM~ Y OF THE INVENT ION
In accoxdance with the present invention~ there i~ pro~
vid~d a low-pro:Eile dual control ~railable rai:Lway switch
3 r ~
which includes a pair of switch points ancl a modularly con-
structed opera-ting machine for moving the swi-tch points he-
-tween -two extreme positions. ~he swi-~ch points are connected
to the operating machine by an operating rod. The operating
machine includes a pivo-tal output crank which is connected
to the operating rod by an adjustable eyebol-t which may vary
the stroke of the opera-ting rodO The pivo-tal crank includes
a crank arm which is connec-ted to an over-the-center toggle
mechanism which spring biases the switch poin-ts in bo-th of
the two extreme positions. The toggle mechanism includes a
compression spring and a pair of telescoping mernbers which
have their remote ends journaled in self~aligning spherical
bushings. The respective ends of the pivo-tal crank are
journaled by self-aligning spherical bushings~ The pivotal
crank is geared by a pair of bevel gears to a main drive
shaft which is journaled by a pair of self-aligned bushingsO
The main drive shaft includes a spur gear which meshes
with a gear train. The gear train is coupled by an elec-tric
elutch to an electric motor which is adapted to power drive
the switch points ~etween their two extreme positions. A
hand throw lever is coupled to the main drive shaft for
manually shifting the switch points between -their -two ex-
txeme positions. A cut~out switch disrup-ts the electrieal
circuit to the electric motor and clu-tch before i-t is pos-
sible to manually throw the switch. The pivo-tal crank
includes a plurality of cam surfaces which cooperate with
cam followers for controlling the electrical condition of
- 5 -
',J~
motor raversing and cut~o:Ef swit:chesD A. wat~3r tight w~:`Lded
housing and r0moval cover protect the internally mount~d
compononts a~gain~t inclsment weath~r and adv0r~e environ~
mental conditiorlqu
DESCRXPTXON OF THE DR~WI:NGS
The above objects and oth~3r attend3nt :Eeatures and ad-
vantage~ will become more :Eully eviderlt Erom th~ Eollowi.ng
detai:led descriptiorl when con~idered in connect.ion with th~
accompanying drawings wherein:
FIG. 1 is a partial ~chematic view of a railway ~witeh
and a top plan view with part~ bxoken away of the ~witch
operating machine having i~8 cov~r removed to show in more
d~tail the various internal a~ompon~3nt~ or elemant~! of lthe
suba~sembli2~ of the operating machine~,
FIG. 2 i~ a ~ectionalized elevAtional vie~ with the
cover .i.n place of the ~witch operating machine taken ~ub-
stantially along 7ine~ II of FIG. lo
FIG~ 3 is an external and elevational vi0w of the ~witch
operating machine a~ viewed from the hand throw lever end,
DETRILED DESCRIPTIO~ OF TEI~ O~I
Referring now to the drawing wh0n l.ike par~ are de-
picted by like refererlce numeral~ in each of the figures~
and in particular to FIG~ 1~ the nun~er 1 sche~atically
de3ignates a right-hand rail.way ~witch layout with the let
point closedO The .rai.lway switch 1 includes a pair oE stock
or running trrlck rail~ la and lb and two movable witch
point~ 2a and 2bo The ~tock running rails are generally
dispos~d on tie plates (~ot sho~n~ which are secured tv
wooden cross tie~ 3 in the u~ual well known manner~ e
movable switch points 2a and 2b are fastened together by a
head rod 49 r~he rai:L~ay switch 1 may be deined as occupying
5 iks noxmal position when khe movable switch point 2a i~
engaging the stock rail la while the movable switch point 2b
is spaced from the stoc]c rail lb, a~ illuskrated in FIG. 17
Conversely, the railway ~w.itch 1 may be defined as occupyi.ng
it~ reverse position whan the mova~lo point 2b engages the
stoclc rail lb while the movable poink 2a is spaced from the
stock rail la~
It w.ill be sean that tha ~witch machina or operating
mechanism 5 cooperates with and is ~uitahly secur3d to the
tvps of cross ties 3 adjacent the outer side of the ~tock
rail lb~ As shown in FIGSo 1 and 3, a lateral ex~ending
plate 14 and a pair of vertical end reinforcing plates 15
are w~lded to each side of khe housing 6 for facilitating
the disposition between and attachm0nt to a pair of cross
ties 3 with the usual spacing~ In actual practice, the
switch machine may be attached to the ~op of the ties 3 by
suitable lag bolts or the like in a conv3ntional manner~ The
operating machanism 5 includes a plurality of individuall.y
romovable subassen~lie3 or modulars which may be easily main~
tained~ repaired and replaced from the ~op side of a shallow
rectanguJar metal housing or case 6. The housing 6 i3 a
water--t.ight wellded casing which houses and supports the
eight subasse~lies o~ tho mechanism 50
In ~iewirly FIGSo 2 and 3" it. will be s~en that a h.inged
removable cover 7 cooperate~ with the top of the hou~ing 6
and includes a rubber gasket 8 which i~ glued in a paripheral
slot 9 :Eormed on th~3 under~ide thereoEO The gasket 8 e:Efec-
5 t:i~7ely seal~ th~ internal compon,ent o:E the mechani~m frommoisture" dirt, dust ans~ othe~ foreign material whlch i~
cornmon place in a rail:road mi:lieu., In practice;, the back~id~
of the housing is provided with a pair of adjustable T-shaped
hinge pins 10 which cooperate with ~lotted ear~ 11 which are
welded to the cover 7" A ha~p 12 and s:taple 13 ~re attached
to th~ ~ront-~ide oLE the housillg 1 and co~er 7i. rhe ~tapl2
accommoda~te~ the shackle o~ a padlock or the like (not .~hown~
~or preventing unauthorized entry and tamper~ng with the
swit~h mechani~m~ The switch mechani~m has been de~igned
such that the top of the cover 7 i~ slightly below the top
of the head oE track rail 2b so that ths switch machine 5
may generally be ~ituated right next to the rail without any
clearance problemsO Thus, the switch machine 5 may be dis-
posad as close to or as far away from the track rail a~
desired~
In viewing FIGo 1~ it will be seen that the switch
points 2a and 2b are interconnected to tha operating me~hanism
5 and are moved between their normal and reverse positions
by means of an operating or throw rod 16 which may be con~
nected to the haad rod 4 by a conventional adjustable switch
basket (no-t shown). Vrha operating rod 16 pas~s through a
suitab:Le central opening pxovided in the back side of the
¢~
housing 5. A flexible rubber boot 17 has a reduced end
clamped -to the operating rod 16 and has an enlarged end
attached to -the exterior of the back wall of housing 6
to prevent the entrance of moisture, dirt, dust and any
other foreign material.
In viewing FIGS. 1 and 2, it will be seen tha-t the
switch machine 5 basically includes eigh-t separate sub~
assemblies or modules, namely~ a toggle spring mechanism
20, a main output crank 21, a main shaft 22, mo-tor-clu-tch~
transmission 23, a structural base or housing 6, a cover 7,
the electrical con-trol contacts and connec-tion -terminals
24, 24a, 24b, 24c, 24d and 24e and a foot pedal and hand
throw lever assembly 25.
The toggle spring mechanisrn 20 includes a pair of
elongated telescopic members 30 and 31 which are surrounded
by a compression spring 32 for a~sisting and biasing the
switch points 2a and 2b to both of the extreme positions.
The member 30 is a rod-like bolt having an enlarged head
30a formed on one end. The enlarged head 30a accommodates
the outer race of a self-allgning spherical bushing 33 which
receives a pivot pin 34. The pivot pin 34 is bolted to the
top of an upright block or stanchion 35 which is welded to the
hottom of housing 6. The intermediate portion of the bolt
like member 30 is provided with an annular collar 36 against
which is seated one end of spring 32. The o-ther end of
spring 32 is seated against an annular collar 37 formed on
the enlarged bifurcated end of member 310 The other end of
3~
the bol-t member 30 is -threaded and is fitted into member 31
which is hollowed ou-t to receive a hexagonal spring retainer
nu-t (not shown). rrhe hexagonal nu-t is adapted -to slide wi-th~
in the ma-tching hollowed out cavity as the -toggle spring
mechanism contracts and expands during movemerl-t of -the
switch points~ As shown, the bifurcated end of member 31 is
pivotally connected to a crank arm 38 which includes a self-
aligning spherical bushing 39 as shown i.n FIG. 1. A pivot
pin 40 passes through aligned holes in the bifurcations and
the center of bushing 39 and is held in place by a pair oE
cct-ter pins ~1.
The main output crank 21 is pivotally connected at its
respective ends by bearing plates 42 and self-aligned
spherical bushings 43, one of which is shown in FIG. lo The
operating rod 16 is pivotally connected to an adjustable
threaded eyebolt 4~. As shown, a pivot pi.n 45 interconnects
the eyebolt 44 to the operating rod 16 and is held in place
by a cotter pin 46. The eyebolt ~4 is screw threaded into a
threaded hole formed in central body por-tion of -the mai.n ou-t-
~0 put crank 21. .[t will be appreciated that the moment armo:E the eyebolt 44 may be varied by turning the eyebolt in-
wardly or outwardly to adjust the stroke of the operating
rod 16. Thus, the stroke of the switch machine may be ad
justed to between three and one hal:E (3-1/2) inches to six
(6) inches with a. switch basket or be-tween four (4) inches
to six (6) inches without a switch basketO It will be seen
tha-t the crank 21 includes a bevel sector gear ~7 which
meshes with a bevel gear 48 mounted on -the end of the main
-- 10 --
3~
shaf-t 22. The bevel gear ~8 includes a collar portion 48a
which is secured by a suitable set screw 48b and by a nut
and lockwasher ~8c for attachmen-t to shaf-t 22. The shaft 22
is rotatably supported by a pair oE spherical bushings 49 and
50. The bushing ~9 is carried by a pillow block 51 while -the
bushing 50 is bolted to the front wall of -the housing 6. As
shown, a spur gear 53 is carried by -the main shaft 220 The
spur gear 53 meshes with the output gear of a gear -train
transmission 5~ which provides a mechanical advan-tage to
necessitate less torque and places less demand of the elec-
tric motor 56. The input of the gear train 5~ i5 connec-ted
to the armature plate of an electromagnetic clutch 55. The
electromagnetic stator of the clutch 55 is connected to the
drive shaft of an instantaneously reversible d.c. ~r a.c.
electric motor 56. In practice, the electric motor, clutch
and gear train are constructed as a unitary assembly so that
all three units are bolted together and are replaceable a-t
any given time.
As previously mentioned, the switch points 2a and 2b
may be manually shifted between their two extreme positions.
Thus, an externally mounted hand throw lever 58 is disposed
at the front end of the switch machineO The hub 59 of the
lever 58 is connected -to -the end o r the drive shaft 22. A
handle 60 is provided at the free end of the lever 58 to
allow a maintainer, yardman or brakeman to manually throw the
railway switch. A foot pedal pivotal ~a-tch 61 is normally
locked by passing the shackle of a lock (not shown) through a
- lL -
staple 62. The latch 61 may he secured to the front wall by
suitable -threaded s-t.uds (not character~ ecl). The latch 61 in-
cludes an upper hook por-tion 63 which prevents -the lever 58
from being lifted when in its loc]ced position. The latch 61
includes an inward depending finger 64 which cooperates with
a r -shaped interlocking lever 65 which is pivoted about
the bolt 66 and spacer 67 centrally mounted to -the fron-t wall
of the housing 6. When the latch 61 is unlatched by step--
ping on the serrated pedal por-tion 68, the lifting of the
lever 58 will cause the cam 69 to engage the right hand end
or leg of i.nterlocking lever 65 as viewed in FIG. 3. This
causes the interlocking lever 65 to rotate in a cockwi.se di-
rection so that the left hand end of the lever engages the
finger 6~ which prevents the latch 61 from ~eing returned to
its latched position until the throw lever 58 is returned to
the position shown in the drawings.
As shown in FIG. 2, a slide or plunger rod 70 has one
end pivotally connected to the pedal latch 61 and includes an
adjustable cam member 71 which is screw threaded on the
other end thereof. As shown, the cam member 71 cooperates
with a roller operated lever 72 of a conventional miniature
cut-out switch 73 which controls a pair of internal electrical.
contacts to open and close the control circuit for the elec-
tric motor 56. Normally, the lever roller 72 rests on the
smaller diameter surface of cam 71 so that the contacts of
the cut-out switch 73 are closed. However, when the pedal
latch 61 is pivotally depressed by foot of a maintainer or
_ 12 -
.~
bra]c~man~ tha slide rocl 70 is moved to the right as viewed
in FIG~ 2r and the larger diameter cam surface of mernber 7L
depress~s the roller levPr 72~ I'he depression oE the roller
lever 7~ causes the opening of the electrical cut-out. con-
S tacts which causes the inlterr1lptic)n o:E the motor controlcircuit and prevents automatic operation o.f tha switch
mechan.i~m 5.
In viewing FCG~ lt it will be scen that the main output
crank 21 is providad with our adju~table sector cam surfaceæ
81a, 81b and 81c, 81d ~ich cooperat0s the roller levar~ 82a~
82b and 82c, 82d o the conventional miniatura motor rever~
and cut-out swikches 83a, 83b nd 83Co 83d~ respectivaly~
The reversa and cut-out switches are mountad to the respective
tines of a Y-shaped bra~ket 84 which i~ bolted t3 the in~ide
~5 o~ k~e back wall of case 6. Tha cam surface~ depres~ and
releas~ the roller levers to open and close the internal
electrical contact~ of the reverse and cut-out ~witches to
interrupt and establish the appropri.ate circuits ~o thak the
switch machine may be power driven between its normal and
rever~e position~. ~he element 24a is an electrical power
supply which converts the 110 vo1t a/c. voltage into a ~uit-
able dnc~ voltage for operation of the d~co electromagnetic
clutch 55. The element 24b is a current sensor and ovaxload
relay which senses when excessive ~urront is being drawn by
the motor 56r For examplo~ if the swit~h points are blocked
by a piece of coal, a stone or an ice build~up~ the motor 56
wi.ll draw excessiva current which causes the over I oad relay
13
tQ interrupt the control CirCIlit to the motor 56 so that the
s~i.~ch poin~s may be returned to their unobstructed po~ition~
The elemant ~.4c i3 a æt.andard terminaL board having a plur-
ality of A~R connectors which permit~ all the nece~sary
conrlecti.ons between the internal and ext.e.rnal e:lectrical
leads~ Irhe element ~4d i~ a Jon.es strip which allows easy
~onnection o:E the el~ct:r:ical leads of motor 56 to the wire
harness 75 o~ the switch machine~ The element 24e is a
magnetic type of revers.ing contactor which i~ controlled by
10 the revar~ing switches B~b and 82c.,
Let us now assume that the ~witch points 2a and 2b are
in thei.r normal po~ition as shown in FIG O 1 and that it i~
necessary to automatically move the swit~h points from their
normal to their reverse po~;i.tion by energiæirlg the reversible
electric motor 56~ As previously mentioned, automatic opera~
tion of the switch machine 5 may be remotely controlled by
either a computer in a fully automated classification yard
or a yardmastex in a semi automated clas~ification yard.
When the contxol circuit is closed, the alectric motor 56 as
well as the electromagnetic clutch 55 ~ecome enorgizedO The
rotational movement of the armature of the a~cO or d,c.
motor 56 is coupled hy engaged clutch 55 to the input of gear
train 54~ The gear train 54 transposes the high speed rota-
tion into a lower speed so that the output gear o~ the gear
train 54 conveys a relative high torqua to the spur gear 53O
~he rotational movement of gear 53 is coupled by shaft 22 to
the bevel year 48 which drives the beval sector gear 47O The
- 14 ~
3~
bevel sectox gear 47 rotates approxlmataly 90 degree~ sc that
the main crank 21 al~o undergoe~ count0rclockwi~e displacs~-
ment of approximately 90 degxees, as v.iewed in FIGg 2. Thu~,
the crank arm 38 will be displac~sd :Erom the position ~hown
by solid 1ine to the position shown in phan~om 90 th~ the
pivotal eyebolt 44 irnparts an inward longituda]. movement to
the operating rod 16~ Thus, the sw:it.ch points are moved from
their normal to their re~er6a position in which the switoh
point 2b engages running rail lb while tho ~witch point 2a
is 6paced from the runn.ing rail la~
Let U6 now regress a moment to the point where the bevel
sector gear 47 has drivan the output crank 21 and crank axm
38 to approximately 45 degree~ of their total movement~
Under this oondition, the telescopic membar3 30 and 31 axe
~ully depre~sed and khe coil spring 32 i6 fully ~ompre~sed~
Now the cam 81c releases the le~er 82c so that khe xeversing
switch 83c closes the normal motor circuit so that the switch
machine may be moved ba~k to its norrnal posiition in case the
switch point 2b encounters an obstruction. ~ow when the
crank 21 and crank arm 38 pass the top dead center point,
namely, the 45 degrees mark, the ~pring 32 begln~ ~o expandr
and the toggle spring rnechanism 20 ~tart6 to assist the
electric motor in driving the switch points to kheir reverse
posi~ionO At ,some point be.Eore the end of the full stroke~
the cam surface 81a causes the opening of the normal cut~out
switch 83a for deenergizing the clutch 55 and motor 56~ It
will ~be appreciated that in addition to assisting in the
- 15 ~
movem~nt of t:he switch point, the spring 32 biases the swit~h
points 2a and 2b in ei~her of their extrem~ positions~ Xn
actual practice~ the spxing 3~ provide~ a minimum holding
or bia~ing :Eorce of 1000 lb~ when the ~pring i~ 600 lb~o
per .inch, and when it is preload~d at 1-2~3 inches, The
cycie tlme ~or operating the ~witch po:Lnts betwe~n their
two extrelne po~itions i~ approximately 2 ~conds. It will
be appr~ciated that ths hand thr~w lever 58 remains ~tation~
ary during the power operating mode due to a di~engagemsnt
featuxe built into the hub 59~
If it i5 de~ired to mo~e the ~witch po.int~ back to
their normal position~ it is simply n~ce~ary to re0nergize
the electric motor 56 and th~ electromagnetic clutch 55 so
that a rever~ing procedure o~cur3, Th~ motor 5~ now rotates
in the opposite direction ~nd drives the output crank 22 in
a cloc~wise direction through the clutch 55, gaar train 54
spur gear 53, shaft 22 and ~he bevel g~ar 47 and 48~ The
cam 81b release~ tha levsr 82b and close~ tha reversing
switch 83b near mid stroke9 and the cam 81d opens the raverse
cut-out switch 83d near the end of the operating ~troke~
Thuso th~ motor 56 and the toggle spring linkage move the
output crank 22~ crank 47 and eyebolt 44 in a clockwise dir~c-
tion to shift the op~rat.ing rod 16 outwardly so that the
switch points assuma their normal po~ition as 3hown in FIG~ lo
Let us assume that the railway switch ls in its normal
position as sh~wn in FIG~ 1, and that a railway vehicle is
appr~aching the switch po~ition on the ~witch point 2~ and
~ 16 ~
3~
the vppoC~ite sid ~ ng or turll~out rail (not characterlxed) ~
Urlder thi.s concliti.on~ a tra:iling action ~will oc~ur when -the
:Eor~ard ~heel of the railway veh.icle forces t:he switch point
2a to operl~ ~husO both o:~ the switch point:3~ which axe
tied togethe:r by xod 3 j, will be shi~ted Erom their normal
to reverse positiorl as the vehicle pa~ses through the rail
way switcllo Ik will be ~een that the throw rod :1.6 move~
in~Arardly and f~auses countercloc}cwise rotation of the crank
21 and crank arm 3B through eyebolt 44, The movement o the
crank arm 22 cau~e~ the compress.ion of the spring togglo
link 20~ The rotation of the crank 21 is tran~mitted by
bevel gears 47 and 48 as will spur ~ear 53 to the year train
transrnis~ion 54D Ho~7ever, since ~the clutch 55 i~ desnergi~ed~
the motor 56 is decoupled by the gear train S3 so that the
~orce due to the residual magneti~m of t~e motor need not be
overcome during a trailing actionO lt will be ~een that once
the crank arm 38 pa~ses dead centert namely~ the 45 degree
pointO the compressive force of the ~pring 32 will drive the
switch point3 to their rever3e position, AgainO the spring
orce o~ a 1000 lbsJ/inch will hold the point~ in the rever6e
positionO The oper~tion of a t.railing action from the
re~ersa to the norma] position ifi sub~tantially the ~ame
except the movements are rever~ed and the switch point 2b
is angaged ~y th~ front wheel of the pa~ing railway ~ehicle.
Let us again assume that the railway ~w.itch is in it~
normal position as shown in FIGo 1~ and that it iB desirable
to manually ma.~ipulate the ~witch points to their reverse
- 17 -
position~ Under thi~ conditionO a yardman; brakeman or
maintainer will normally unlock and remove the lock from the
~taple 62 and then will step on the foot pedal. 68~ This
pivots the latch member 61 which cau~e~ the rod 70 to shift
and re~ult~ in the depression of lever 72 by the cam 7]..
Thus~ the contact~ or cut~out 6witch 72 are opened to inter-
rupt the circuit pakh to the motor 56 and ciutch 55 ~o that
thP operating lever may be ~aEel~y thrown by hand without
dangex of injury to a worhman by an inadvertent remote powor
operation9 ~axt, the maintainer will normally grab the
handle 60 and will permit the hub 59 to be engagoable to the
drive shaft 22~ As the lever S8 is pick*d up and rotated,
the cam 69 engages the intarlocking lever 65 and prevents
the latch 61 from being closed. ~ha rotation is tran~mitted
via spur g~ar 53 to the gear txain 54 and via bevel gears 48,
47 to the output crank 21 and crank arm 389 The angular
displacement of crank 21 i~ tran3posed to linear movement of
the throw rod 16 via eyebolt 44~ The angular di~placemant of
the crank arm 38 causes the contraction of the ~pring toggle
20 linkaga 20t and at slightly boyond the mid-strokl3 the com-
preR~ivn spring 32 completes the movement of th~ ~witch
points to their revar~e positionO The disengay~ment feature
of the hub 59 and the end of ~ha~t 22 allcws the lever 58 to
be safely lowerQd to its oppo~ite position or to be ~a~ely
25 returned to the :la tch stand~ Thusp no tor~ue i~ applied to
the lever 58 when the spring 32 dxive~ switch point to
eithar of the two extreme positionq so that there i~ no
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L~t.;3~
danger of injury to the irldlvldual dur.irlg t~e manual throw~
ing of the railway ~twitch. It wi.~ 1 be appxeciated that th~
proei3dure for moving the sw.ikch polntct from their reverse to
normal po.si.tion i~ sub~:tantially the ~aml3 exc~spt the lever
5 58 i~ rot:at~d in a counte3.rclockwi te d:Lrectior~ as viewe~l in
FIG. 3i Further~ ~he shaft 22" ~pur gear 53" gear trairl 54~
k:)evel gear 480 47, the crank 21" t~ae eranlc arm 38 and eyebolt
44 ar~? rotatad in th~ opposit~ direction whil~ the ~hr~w rod
16 is moved outward:Ly to move the ~witch ps: ints to theix
10 normal pos i t ion~ .
ThusO there has boerl described th~ variou~ al~ernative
method~ of operating the switch bet:we~n its normal po~ikion,
a~ shown in the drawing~ and it~ reverse po~ition~ According
ly, the Rwitch points may be effectively moved rom one ex-
treme po~ition to the other extreme pG~ition in any one ofthreo difarent way~, namely~ power driving the ~witch
point~ by energizing the electric motor 56~ manually m~ving
the switch points by throwing the hand operating l~ver 58,
and trailing the switch point~ by the wheel~ of a railw~y
vehicle pas~ing through the 3witch by moving ths operating
rod 160
Although I have herain illustrated and d~cribsd only
one form o~ apparatu~ embodying my inventionO it is under-
stcod that various changes, alt2ra~ion~l modifications and
oquival2nt~ may ba made and used by tho~e skilled in th~
art which fall. within the spirit and scop~ o~ the claim~ of
m~ inventionO
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