Note: Descriptions are shown in the official language in which they were submitted.
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SWITCH MACHINE WITH SWITCH POINT CONNECTORS
CROSS REFERENCE TO RELATED APPLICATIONS
Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED
RESEARCH OR DEVELOPMENT
Not Applicable
BACKGROUND OF THE INVENTION
Field of the Invention - The present invention is in the field of railroad
switching
devices, namely the equipment which is used to displace railroad switch
points. More
specifically, the invention refers to a pivoting connector which connects each
of the
operating rods of the switching device to the associated switch point, in a
non-binding
relationship.
Background Art - A railroad switch point consists of tapered rail sections
which are
capable of being selectively displaced between two different lateral positions
at a rail
switch and then locked in the selected position, in order to facilitate the
desired
routing of a train passing through the switch. The two switch points are
typically
displaced by rods extending from an assembly which is referred to herein as a
"switch
machine". Inside the switch machine the rods are usually connected to a motive
mechanism which provides reciprocating rectilinear motion, controlled by a
power
unit which is usually placed to one side of the rails.
Such a device is described in Italian Patent No. IT] 246656, to the inventor
herein.
The device described in that patent operates switch points which are
independent, or
disconnected, from each other, and it is not applicable to the problem of
operating
switch points of the interconnected type, i.e. of switch points connected to
each other
by transverse bars. Switch machines of the interconnected type are shown, for
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example, in U. S. Patent Nos. 5,806,809 and 6,149,106.
The switch machine combines the switch point movement and switch point locking
functions into a single mechanism to reduce mechanical complexity, enclosing
the
mechanism in a weather-proof housing, incorporating sensors and other
electrical
control components in the housing and locating the housing and operating
assembly
beneath the switch points and the associated rails.
In such switch machines, binding may occur, as described below, when the
operating
rod does not move along its intended longitudinal line of action, but rather
is
subjected to lateral forces tending to cause it to bind at its attachment to
the switch
point and where the operating rod passes through the switch machine housing. A
bearing and a seal are usually provided at the entry point into the housing,
to align the
operating rod and to seal out water and other contaminants. The outer end of
each
operating rod connects to an associated switch point, and as the operating rod
is
moved into and out of the switch machine housing, this substantially
longitudinal
movement of the operating rod is used to apply force to move the associated
switch
point laterally. The lateral movement of the switch point requires some change
in the
angle between the operating rod and the switch point, because the switch point
is
actually pivoting about a pivot point at the other end of the switch point
rail section.
So, this change in angle can apply a lateral reactive force on the outer end
of the
operating rod, causing the inner end of the operating rod to apply substantial
lateral
force to the bearing and seal mechanism through which the operating rod enters
the
switch machine housing. This lateral reactive force can cause premature
failure of the
seal and binding of the operating rod relative to the housing, which can cause
the
switch machine to lock up.
It would be desirable to have a means for preventing this application of
lateral force to
the outer end of the operating rod, in order to eliminate the binding of the
operating
rod at the housing, and in order to preserve the condition of the housing
seal.
BRIEF SUMMARY OF THE INVENTION
The present invention is illustrated as implemented with a switch machine for
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operating a switch having switch points. Two operating rods extend from either
side
of a fixed housing positioned between intersecting rails, to the movable
switch points,
with the rods being capable of longitudinally sliding relative to the housing.
Movement of the operating rods moves the switch points between two positions
between the pair of rails. The switch machine operates to hold the rods in
place to
selectively lock the operating rods and the switch points in a desired
position.
In accordance with the present invention, a pivoting connector assembly is
provided
on the outer end of each operating rod. In one form of the invention, a socket
mounted or formed on the outer end of the operating rod has a vertically
oriented bore
into which a pivot shaft is positioned, with a collar at the top of the
vertical pivot
shaft. A horizontal bore is formed in the collar, and the collar bore is
adapted to pivot
about the vertical axis of the pivot shaft. A horizontal pivot pin is attached
essentially
parallel to each switch point. This pivot pin is positioned through the collar
bore, in a
sliding arrangement. As the operating rod moves the switch point laterally,
the collar
slides along the horizontal pivot pin by a slight amount. Further, as the
switch point
moves laterally, the collar pivots about the vertical axis to maintain the
alignment of
the collar bore axis with the horizontal axis of the pivot pin. This prevents
the pivot
pin from imposing a lateral reactive force on the operating rod.
The novel features of this invention, as well as the invention itself, will be
best
understood from the attached drawings, taken along with the following
description, in
which similar reference characters refer to similar parts, and in which:
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
Figure 1 is an exploded view of the lower components of a switch machine which
can
implement the present invention;
Figure 2 shows the switch mechanism holding the switch points in the full
right
position in the locked mode;
Figure 3 shows the switch machine in the full right position of Figure 2, but
with the
control rod moved to the left to unlock the switch machine to move the switch
points;
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Figure 4 shows the switch machine with the control rod moved further to the
left to
move the switch points from the full right position toward the full left
position;
Figure 5 shows the switch points moved to the full left position;
Figure 6 shows a switch machine incorporating a modification according to the
present invention;
Figure 7A shows a schematic view of the rail layout of a switch point;
Figure 7B shows a top plan view of the apparatus in Figure 6;
Figure 8 shows a perspective view of a pivoting connector according to the
present
invention;
Figure 9 shows a first form of the connector according to the present
invention;
Figure 10 shows another form of the connector according to the present
invention;
and
Figures 1 1 and 12 show sectional views of a collar on the connector along
line 1 l-I 1
of Figure 10.
DETAILED DESCRIPTION OF THE INVENTION
As seen in the attached drawings, the switch machine includes three basic
types of
fixed components: a fixed housing 1; a plate 2 fixedly mounted within or
otherwise
attached to the housing 1; and two guides 3 fixedly mounted within or
otherwise
attached to the housing 1, below the level of the fixed upper plate 2. A
capture
mechanism, including a plurality of capture elements and a shifting body, is
used to
selectively engage and disengage two operating rods 4, 5 to and from the fixed
upper
plate 2. More specifically, an upper set of interlocking or capture elements
are
provided to selectively interlock or engage the two operating rods 4, 5 with
either the
fixed upper plate 2 or the shifting body within the housing 1. As part of the
upper set
of interlocking elements, the fixed upper plate 2 is provided with two ball
seats 24
mounted on the upper side thereof. Each of the ball seats 24 houses a
corresponding
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disk or follower plate 21 which can be completely inserted in its respective
ball seat
24 against the action of a spring 22. A lower set of interlocking elements are
also
provided to selectively interlock the shifting body with either the two fixed
lower
guides 3 or a control rod S. As part of the lower set of interlocking
elements, each of
the two fixed lower guides 3 is provided with two transverse pin seats 32,
with each
pin seat 32 having sloping walls.
The movable components include the two operating rods 4, 5 which slidingly
contact
the lower side of the fixed plate 2, and which move the two switch points Al,
A2
transversely. The switch points Al, A2 are connected by one or more transverse
bars
9, so that the switch points A], A2 always move together and maintain their
transverse spacing. The switch points Al, A2 can move so that they contact
either of
two stock rails Cl, C2 for the purpose of directing a passing rail car along
the desired
track. Each operating rod 4, 5 is provided with a through hole 41, 51 sized to
allow a
ball 42 to pass therethrough, with each ball 42 being sized to pass into one
of the ball
seats 24. The thickness of each operating rod 4, 5 in the vicinity of its
respective
through hole 41, 51 is at least half the diameter of the ball 42. One skilled
in the art
will recognize that a pin of suitable configuration could be used instead of
the ball 42,
and it could pass through corresponding shaped slots instead of the through
holes 41,
51.
The shifting body within the housing 1 includes a skate 6 and an intermediate
shift
assembly 7. The skate 6, which slidingly contacts the lower sides of the
operating
rods 4, 5 is provided with two ball slots 61, 62 recessed into its upper
surface,
oriented transverse to the longitudinal axis of the skate 6. The wall of each
ball slot
61, 62 closest to the center of the skate 6 slopes upwardly toward the center.
Each
ball slot 61, 62 is able to accept one of the balls 42, with the depth of the
ball slot 61,
62 being no more than half the diameter of the ball 42. On the lower side of
the skate
6 a semi-cylindrical lower central cavity 63 is provided, with the axis of the
semi-
cylindrical cavity 63 being parallel to the longitudinal axis of the skate 6.
Two
transversely oriented stabilizing recesses 65 are provided in the lower side
of the skate
6, one stabilizing recess 65 being positioned beyond each end of the central
cavity 63.
Each stabilizing recess 65 is capable of housing one transversely oriented,
cylindrical,
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end stroke stabilizing pin 66.
The intermediate shift assembly 7 is positioned in contact with the lower side
of the
skate 6, with the longitudinal axis of the shift assembly 7 parallel to the
longitudinal
axis of the skate 6. The shift assembly 7 includes a hollow central cylinder
71,
provided with a cylindrical sleeve 72 fixedly surrounding each end of the
central
cylinder 71. Each sleeve 72 has two symmetrical wings 73 extending radially
therefrom, transverse to the longitudinal axis of the shift assembly 7. The
upper
portion of the central cylinder 71 and the cylindrical sleeves 72 of the shift
assembly 7
can be securely inserted into the central cavity 63 on the lower side of the
skate 6.
The symmetrical wings 73 rest flat on the upper sides of the fixed guides 3,
with the
lower portions of the central cylinder 71 and the cylindrical sleeves 72
positioned
between the fixed guides 3. Through slots 74 are provided in each of the wings
73,
through which transversely oriented, cylindrical, shift pins 75 can pass in
order to seat
in the pin seats 32 in the upper sides of the fixed guides 3.
The control rod 8, controlled by an external power unit not shown in the
drawings,
enters the housing I from one side. The control rod 8 can slide through the
whole
shift assembly 7, and it is provided with U-shaped right and left shift forks
81,_83
straddling the outer ends of the sleeves 72. The shift forks 81, 83 are
fixedly mounted
on, or integral with, the control rod 8, and they can partially slide over the
tops of the
wings 73 of the shift assembly 7. On the upper surface of each of the forks
81, 83 an
approximately semi-cylindrical transverse groove 82 is provided, to receive
the
stabilizing pins 66 which are housed in the stabilizing recesses 65 in the
lower side of
the skate 6.
An external power unit (not shown) can be provided outside the rails, and
mounted to
one side of the housing 1, with a drive shaft, as is known in the art, passing
under the
rails and connected to the control rod 8 for achieving bi-directional
longitudinal
movement of the control rod 8.
In Figures 2 to 5, the sequential steps of the normal functioning of the
switch machine
are illustrated, and the relative positions of the switch machine components
are
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shown. In Figure 2, the right switch point A2 is in contact with the right
stock rail C2
at the full right end position of the stroke, and the control rod 8 is
stabilized relative to
the skate 6 by the left end stroke stabilizing pin 66 which is seated in the
groove 82 on
top of the left fork 83 and partially housed in the left stabilizing recess 65
in the lower
side of the skate 6. In this position, the right operating rod 5 is captured
relative to the
fixed plate 2 by the right ball 42, which is partially housed by the right
through hole
51 in the rod 5 and partially housed in the right ball seat 24 of the plate 2.
Of course,
because of the rigid connection between the switch points Al,_A2 effected by
the
transverse bar 9, the left operating rod 4 is also held in place relative to
the fixed plate
2. Therefore, in the configuration shown in Figure 2, the switch points A], A2
are
held in place at the right end of the stroke. Further, in this configuration,
the shift
assembly 7 is captured or latched relative to the fixed guides 3 by the left
shift pins
75, which are partially housed in the through slots 74 in the left wings 73,
partially
housed in the left pin seats 32 of the fixed guides 3, and held in place by
the left fork
83 extending over the through slots 74. This latching prevents any movement of
the
shift assembly 7, such as might be caused by vibration, in order to lock the
switch
machine in this position.
When it is desired to move the switch points A], A2 from the right end
position
toward the left end position, movement of the control rod 8 toward the left
part of the
drawing, as indicated by the arrow in Figure 2, is caused by the
aforementioned power
unit. This movement of the control rod 8 first forces the left end stroke
stabilizing pin
66 upwardly out of the left semi-cylindrical groove 82 into the left recess
65, allowing
the control rod 8 to move leftward. In Figure 3, shortly after this movement
toward
the left is initiated, it can be seen that the inner edge of the right fork 81
is abutting the
right shift pins 75 which in turn exert a force to the left on the left walls
of the through
slots 74 in the right wings 73 of the assembly 7. Further, the region over
each left
shift pin 75 is cleared by the displacement of the left fork 83 toward the
left. It is at
this point that the shift assembly 7 and the skate 6 are unlatched, and they
can begin to
move to the left relative to the fixed guide 3, in response to the force
exerted by the
right fork 81. Because of the extended length of the left ball slot 61, the
control rod 8,
the skate 6, and the shift assembly 7 can all move to the left relative to the
left
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operating rod 4, even though the right ball 42 is still capturing the right
operating rod
in place. As the shift assembly 7 moves to the left, the left shift pins 75
are pushed
up the sloping left walls of the left pin seats 32 by the right walls of the
through slots
74 in the left wings 73, until the shift assembly 7 is completely disengaged
from the
fixed guides 3.
As the control rod 8 continues to move to the left, the right fork 81 pushes
the shift
assembly 7 and the skate 6 to the left, with respect to the operating rods 4,
5, with the
result that the right ball 42 is eventually expelled, by gravity and the
spring 22, from
the right ball seat 24 into the right ball slot 62 in the upper side of the
skate 6. This
releases the right operating rod 5 from the fixed plate 2; at the same time,
the left ball
42 runs along the whole length of the left ball slot 61 on the skate 6. This
sequence of
movements, all initiated by the movement of the control rod 8 to the left, has
the
effect of unlocking the operating rods 4,5, the transverse bar 9, and the
switch points
Al, A2 for movement to their respective left positions. Continued leftward
movement of the control rod 8, the shift assembly 7, and the skate 6 pushes
the left
operating rod 4 to the left, because of the left ball 42 being abutted by the
right wall of
the left ball slot 61 and captured in the left ball slot 61 by the fixed plate
2. This
configuration is shown in Figure 4. Leftward movement of the operating rods 4,
5
continues in this way, displacing the left switch point Al and, in turn, the
right switch
point A2, which is connected to the left switch point Al by the transverse bar
9. The
switch points Al, A2 are thus moved away from the full right position and
toward the
left position.
As seen in Figure 5, leftward movement has continued until the left switch
point Al
abuts the left stock rail Cl, and the left ball 42 is positioned directly
under the left
disk 21 and the left ball seat 24. This positions the operating rods 4, 5 in
their full left
position.
At this left end point of the operating rods 4, 5, continued leftward movement
of the
control rod 8 causes the left ball 42 to be forced upwardly against the disk
21, because
of the slope of the right wall of the left ball seat 61 and resistance to
further
movement of the ball 42 by the left side of the through hole 41. As the left
ball 42 is
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forced upwardly, it compresses the spring 22, until the left ball 42 enters
the left ball
seat 24. Once the left ball 42 rises at least partially into the left through
hole 41, it
creates an interference which prevents the operating rods 4, 5 from moving
farther
relative to the fixed plate 2. However, the operating rod 8, the skate 6, and
the shift
assembly 7 can continue moving to the left because of the extended length of
the right
ball slot 62, until the right shift pins 75 engage the shift assembly 7 with
the right pin
seats 32 in the fixed guides 3.
The assembly made of the operating rods 4, 5, the transverse bar 9, and the
switch
points Al, A2, is also then captured relative to the fixed plate 2 by the left
ball 42. At
this point, the right shift pins 75 have aligned with, and dropped into, the
right pin
seats 32 in the fixed guides 3. Also, the right ball 42 has completed its
displacement
along the right ball slot 62, and it now abuts the right wall of the right
ball slot 62.
This abutment of the right ball 42 with the right wall of the right ball slot
62 has
stopped the leftward movement of the skate 6 and the shift assembly 7 relative
to the
fixed plate 2. However, the control rod 8 and the forks 81, 83 have continued
to move
leftward until the right shift pins 75 are captured within the right pin seats
32 of the
fixed guides 3 by the right fork 81, securely latching or capturing the shift
assembly 7
and the skate 6 relative to the fixed guides 3. Further, the right end stroke
stabilizing
pin 66 has dropped partially into the groove 82 on top of the fork 81,
stabilizing the
control rod 8 relative to the skate 6. This locks and latches the switch
machine at the
full left end of its stroke.
It can be seen that, in this locked and latched configuration, the control rod
8 is not
affected by possible loads which may be exerted on the detached right switch
point
A2. Such loads are transmitted to the switch point A l via the transverse bar
9, and to
the operating rod 4, and they are then absorbed by the plate 2, to which the
left
operating rod 4 is captured. Furthermore, since the right fork 81 captures the
right
shift pins 75 in the right pin seats 32, this prevents accidental shifting of
the switch
machine, which could be caused, for example, by vibrations.
Shifting of the mechanism back to the right is accomplished in a similar
fashion to the
leftward shifting.
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Electrical sensors incorporated in locations in the mechanism such as the
forks 81, 83
act to monitor the correct or incorrect positioning of the mechanism at the
right and
left end points of its stroke. That is, as can readily be seen from Figure 2,
an electrical
sensor in the left fork 83 senses attainment of its rightmost position
relative to the left
operating rod 4, at the right end point of the stroke of the switch machine.
Similarly,
an electrical sensor in the right fork 81 senses attainment of its leftmost
position
relative to the right operating rod 5, at the left end point of the stroke of
the switch
machine. These sensors may be any suitable sensor such as shown for example in
U.
S. Patent No. 6,149,106 and may be engageable with the forks 81, 83 and the
operating rods 4, 5. Alternatively, the sensors may be mounted elsewhere
within the
switch machine so as to sense the position of one element relative to another
element
within the switch machine.
In a first type of irregular functioning of the switch machine, an obstacle
between the
left switch point Al and the left stock rail Cl can prevent the full
displacement of the
switch point Al to abut the left stock rail Cl. The obstacle causes the switch
point A]
to stop advancing, and the displacement of the control rod 8 can not reach the
predetermined end-stroke point. A sensor in the right fork 81 will readily
indicate
that the control rod 8 has not reached the end of its stroke relative to the
operating
rods 4, 5, so that this type of irregular condition is made evident. This
irregular
functioning may then be communicated to associated wayside signalling
equipment or
remotely to a data center communicating with the switch.
A second type of irregular functioning can be caused by the absence of the
stroke rail
Cl in the correct position. In that case, the displacement of the switch point
Al is not
opposed by the stock rail Cl; therefore, the left side of the left through
hole 41 never
offers sufficient resistance to the movement of the left ball 42 to cause the
left ball 42
to react against the sloped wall of the left ball slot 61 and move upwardly,
compressing the spring 22 and entering the left ball seat 24. Therefore, the
skate 6 is
not released from its engagement with the left operating rod 4, and the
operating rods
4, 5 continue to move to the left with the control rod 8. As in the previous
example, a
sensor in the right fork 81, for example, will readily indicate that the
control rod 8 has
not reached the end of its stroke relative to the operating rods 4, 5, so that
this type of
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irregular condition is made evident. Such event is then communicated to other
wayside equipment or a remote data center.
Figures 6 through 12 illustrate connectors, according to the present
invention, for the
switch machine. Figure 6 shows a side elevation view of a switch machine
incorporating this modification, with the switch machine housing l itself
being shown
in section, to show the location of a bearing 102 and a seal 1 04 on each
operating rod
4, 5. The bearing 102 aligns the operating rod 4, 5 to move along a line of
action on
the axis of the internal mechanism of the switch machine, while the seal 104
seals out
water and other contaminants which could cause deterioration or even
malfunctioning
of the switch machine. A socket 106 is provided at the outer end of each
operating
rod 4, 5. Each operating rod socket 106 is pivotably connected to its
associated
switch point Al, A2, by a yoke 112, a pivot pin 108, and a mounting clip 110.
Assume that each switch point Al, A2, along with the respective section of
rail to
which it is attached pivots around an axis, such as the axis 200 shown in
Figure 7A
when the switch point is moved. However, it should be noted that the pivot
radius of
the rail is relatively large compared to the dimensions of the other elements
shown in
Figure 6, and thus the location of the axis 200 is not shown to scale. As
shown in
Figures 7A and 7B, as the operating rod 4, 5 moves longitudinally to move its
associated switch point Al, A2 laterally, it can be seen that the angle 140,
will change
slightly. That is, for example, if the operating rod 5 moves to the right, the
angle 140
between the operating rod 5 and the switch point A2 will increase slightly. If
the
operating rod 5 were locked at a given angle relative to the switch point A2,
the
lateral reactive force imposed on the operating rod 5 by the pivoting switch
point A2
would cause the operating rod to try to pivot in a counter-clockwise
direction, as
viewed in Figure 7B. Similarly, if the operating rod 5 were fixedly attached
at a given
point on the pin 108, pivoting of the switch point would pull the operating
rod 5 to
one side. These types of lateral or pivoting force on the operating rod 5
would cause
it to bind in the bearing 102 and the seal 104. This binding would, at the
very least,
cause accelerated wear and premature failure of the bearing 102 and the seal
104.
Further, this binding could actually lock up the entire switch machine,
especially in
the case where the two switch points are tied together as discussed
hereinabove.
it
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However, the connectors, as described below, are also operative with and
provide
benefit for other between-the-rail switch machines, in which the switch points
are not
tied together, other than via the operating rods.
To prevent this binding, the socket 106, the yoke 112, and the pivot pin 108
have
features which allow the switch point A2 to pivot freely relative to the
operating rod
5, without imposing a reactive pivoting force on the operating rod 5. The same
arrangement is provided at the connection between the operating rod 4 and its
associated switch point Al. As seen better in Figure 8, the operating rod
socket 106
has a vertical bore 1 1 8 therethrough, with the bore 1 18 being centered on a
vertical
axis 120. A clevis pin hole 124 can be provided laterally through the socket
106, and
transversely through the socket bore 118, for use with some embodiments, as
discussed below.
The yoke 112 has a vertical shaft 116, which is positionable in the socket
bore 118,
centered on the vertical axis 120. If not pinned to the socket 106, the yoke
112 can
pivot about the vertical axis 120 of the vertical shaft 116, relative to the
vertical bore
l 18 of the socket 106. The pivot pin 108 is rigidly mounted to the switch
point by
means of the mounting clip 110, with the longitudinal axis 122 of the pivot
pin 108
being oriented horizontally and substantially parallel to the axis of the
switch point.
The yoke 112 is slidingly attached to the pivot pin 108, by means of a collar
114 at
the top of the vertical shaft 116 of the yoke 112. That is, the collar 114 at
the top of
the yoke 1 l2 has a horizontal bore into which the pivot pin 108 is received,
and the
collar 114 is free to slide along the pivot pin 108.
As seen in Figure 9, the yoke 112 has a vertical shaft 116, at the top of
which is
mounted a pivoting collar 114. The collar 114 pivots about the vertical axis
120,
relative to the vertical shaft 116 via a vertical pivot pin (not shown), or
alternatively,
it could be fixedly mounted to the vertical shaft 116, in which case the
collar 114
pivots with the shaft 116. In all cases, a horizontal bore 126 is provided
through the
collar 114, with the collar bore 126 being centered on the horizontal axis 122
of the
pivot pin 108. It can be seen that, as the collar 114 pivots, the horizontal
axis 122 of
the collar bore 126 pivots about the vertical axis 120 of the vertical shaft
116.
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In a further embodiment, seen in Figure 10, the yoke 112 has a vertical shaft
116 and
a collar 114, as before. However, in this embodiment, the collar 114 has an
inner
collar member 128 and an outer collar member 132, as shown in Figures I I and
12.
The collar bore 126 in this instance passes through the inner collar member
128.
The inner collar member 128 can be a truncated spherical member as shown,
positioned in a spherical cavity 134 within the outer collar member 132. It
will be
seen that this allows the inner collar member 128 to pivot relative to the
outer collar
member 132, with the result that the horizontal axis 122 of the collar bore
126 pivots
about the vertical axis 120. In fact, pivoting of the collar bore 126 relative
to the
outer collar member 132 can also have a vertical component as well as a
horizontal
component. If the plane of the switch point movement is not exactly orthogonal
to the
vertical axis 120, this vertical component of the pivoting of the collar bore
126 can be
important to further prevent binding of the operating rods 4, 5. In this
embodiment, as
before, the outer collar member 132 may be fixedly attached to the vertical
shaft 1 l 6,
or it may be allowed to pivot relative thereto.
It should be understood that, whichever embodiment of the yoke 1 12 is used,
the yoke
112 is adapted to allow the axis 122 of the collar bore 126 to pivot about the
vertical
axis 120, in a substantially horizontal plane. This can be accomplished by
allowing
the vertical shaft 116 to pivot in the socket bore 118, by allowing the collar
114 to
pivot relative to the vertical shaft 116, by allowing an inner collar member
128 to
pivot relative to an outer collar member 132, or by any combination of these
three
mechanisms. Where some portion of the collar 114 is adapted to pivot relative
to the
vertical shaft 116, the vertical shaft 116 can be retained to the operating
rod socket
118, by a retainer pin placed in the clevis pin hole 130. Where pivoting is
accomplished by allowing the shaft 116 to pivot relative to the socket 106,
the clevis
pin hole 130 may not be used.
It can be seen, then, that as the operating rod 5 extends, for instance, to
move its
associated switch point A2 laterally to the right, the collar 114 slides along
the
horizontal axis 122 of the pivot pin 108, toward the free end of the switch
point A2.
Simultaneously, the collar bore 126 pivots about the vertical axis 120,
relative to the
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CA 02555727 2012-03-01
74HN 149946
operating rod socket 106. The combination of this sliding movement and this
pivoting movement prevents the imposition of lateral reactive forces on the
operating
rods tending to bend or pivot the operating rod 5 relative to the bearing 102
and the
seal 104.
While there have been described herein what are considered to be preferred and
exemplary embodiments of the present invention, other modifications of these
embodiments falling within the invention described herein shall be apparent to
those
skilled in the art.
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