Rotary guideway switch having guidebeam and/or electric rail structure located above and between guideway tire paths

A rotary switch for a people mover guideway which as a pair of spaced tire paths with a predetermined tire path, guidebeam and electric rail configuration. The rotary switch routes a transit car from one entry guideway path to either two exit guideway paths. The switch inlcudes a switch frame having guidebeam, electric rail and tire path structure on opposite sides of the switch frame, each being compatible with the guideway configuration to provide car routing to the respective paths. Each side of the switch frame member includes at least one tire path in alignment with the corresponding guideway tire path for car routing to one of the exit paths. The guidebeam and electric rail structure on each side of the switch frame member are located above the tire path on the corresponding side of the switch frame member and the other tire path for the guideway when the switch frame member is in respective rotational positions. The electric rail structure on each side of the switch frame member includes three elongated power rails and at least two elongated signal rails and structure for supporting the electric rails on each side of the switch frame member, within the space between the associated tire paths, for electrical connection to collectors on the underside of transit cars that pass over the respective sides of the switch.

CROSS REFERENCE TO RELATED APPLICATIONS 
The following related and concurrently filed and coassigned patent 
applications are hereby incorporated by reference: 
U.S. Pat. application Ser. No. 07/211,723, filed concurrently entitled 
ROTARY GUIDEWAY SWITCH FOR PEOPLE MOVER SYSTEMS and filed by Thomas J. 
Burg, William K. Cooper, Robert J. Anderson, Ronald H. Ziegler and John W. 
Kapala. 
U.S. Pat. application Ser. No. 07/213,206, filed concurrently, entitled 
ELECTRIC COUPLING FOR ROTARY GUIDEWAY SWITCH and filed by Thomas J. Burg. 
U.S. Pat. application Ser. No. 07/211,734, filed concurrently, entitled 
SAFETY LOCKING STRUCTURE FOR A ROTARY GUIDEWAY SWITCH and filed by Thomas 
J. Burg, William K. Cooper and Robert J. Anderson. 
U.S. Pat. application Ser. No. 07/211,725, filed concurrently, entitled 
GUIDEWAY STATION FOR A ROTARY GUIDEWAY SWITCH and filed Thomas J. Burg, 
Robert J. Anderson and Ronald H. Ziegler. 
U.S. Pat. application Ser. No. 07/211,726, filed concurrently, entitled 
ROTARY GUIDEWAY SWITCH HAVING SINGLE TIRE PATH LOADING and filed by Thomas 
J. Burg, William K. Cooper, Robert J. Anderson, Ronald H. Ziegler and John 
W. Kapala. 
U.S. Pat. application Ser. No. 07/211,735, filed concurrently entitled 
SELF-ALIGNING ROTARY GUIDEWAY SWITCH and filed by Thomas J. Burg. 
U.S. Pat. application Ser. No. 07/211,610, filed concurrently, entitled 
SINGLE TURNOUT ROTARY GUIDEWAY SWITCH AND A DUAL LANE CROSSOVER STATION 
EMPLOYING THE SAME and filed by Thomas J. Burg, William K. Cooper, Robert 
J. Anderson, Ronald H. Ziegler and John W. Kapala. 
U.S. Pat. application Ser. No. 07/211,736, filed concurrently, entitled 
DOUBLE TURNOUT ROTARY GUIDEWAY SWITCH and filed by Thomas J. Burg, William 
K. Cooper, Robert J. Anderson, Ronald H. Ziegler and John W. Kapala. 
U.S. Pat. application Ser. No. 07/211,721, filed concurrently, entitled 
IMPROVED ELECTRIC, GUIDANCE, AND TIRE PATH CONFIGURATION FOR A PEOPLE 
MOVER GUIDEWAY and filed by William K. Cooper, Thomas J. Burg, and John W. 
Kapala. 
BACKGROUND OF THE INVENTION 
The present invention relates to people mover systems and more particularly 
to guideway switches for such systems. 
In cross referenced basic patent application Ser. No. 07/211,723 W.E. 
53,893, a general background description is presented and there is 
disclosed the structure and operation of a new rotary guideway switch and 
a new guideway configuration for people mover systems. That disclosure 
embodies a plurality of basic and improvement inventions and accordingly a 
family of patent applications, including the present application and those 
applications listed in the Cross-Reference section, are being filed 
concurrently in correspondence to the respective inventions. 
The present patent application is directed to a rotary guideway switch for 
a guideway having guidebeam and electric rail structure that presents 
special problems for guideway switching, with resolution of those problems 
being facilitated by structuring of the switch for rotary operation. 
SUMMARY OF THE INVENTION 
A rotary switch for a people mover guideway has a pair of spaced tire paths 
with a predetermined tire path, guidebeam and electric rail configuration. 
The rotary switch routes a transit car from one entry guideway path to at 
least either of two exit guideway paths or vice versa. 
The switch includes an elongated structural switch frame having guidebeam, 
electric rail and tire path structure on one side compatibly with the 
guideway configuration to provide car routing to one of the two exit 
paths. The switch frame further has guidebeam, electric rail and tire path 
structure on another side compatibly with the guideway configuration to 
provide car routing to the other of the two exit paths. 
The frame structure on the one frame side includes first frame means 
disposed to provide at least one first-side switch tire path in alignment 
with the corresponding guideway tire path for car routing to the one exit 
path. The frame structure on the other frame side includes second frame 
means disposed to provide at least one other-side switch tire path in 
alignment with the corresponding guideway tire path for car routing to the 
other exit path. 
The frame structure on the one frame side further includes a first switch 
section guidebeam and first switch section electric rail means disposed 
for car routing to the one exit path. The frame structure on the other 
frame side further includes a second switch section guidebeam and second 
switch section electric rail means disposed for car routing to the other 
exit path. 
At least one of the first switch section guidebeam and electric rail means 
is located above the first-side switch tire path and between the 
first-side switch tire path and the other tire path for the guideway when 
the one side of the frame faces upwardly. Similarly, at least one of the 
second switch section guidebeam and electric rail means is located above 
the second-side switch tire path and between the second-side switch tire 
path and the other tire path for the guideway when the other side of the 
frame faces upwardly. 
The frame is supported at its opposite ends by respective shafts with at 
least one of the shafts providing drive force to rotate the switch frame 
between first and second rotational positions in which the switch sides 
are respectively aligned with the guideway paths. 
The invention is described below with reference to the accompanying 
drawings, a brief description of which follows. The Figure numbers of 
sectional views are keyed to reference planes denoted by Roman numerals 
and letters. For example, the sectional view of FIG. 3A is taken through 
reference plane III A in FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
GUIDEWAY SYSTEM 
More particularly, there is shown in FIG. 1 a people mover system 10 in 
which the present guideway switch invention is embodied. The system 10 is 
a schematic representation of Phase 1 of a people mover system being 
commercially supplied by the assignee of the present invention to a 
location in Texas and referred to as the Las Colinas Area Personal Transit 
System. 
The system 10 includes a first guideway lane 12 which extends from a 
maintenance building 14 to a Government Center Station 16 through various 
other stations to a Xerox Center Station which is currently the last 
station on the guideway lane. 
A second guideway lane 20 extends from the station 16 to a Las Colinas 
Boulevard Station 22. Normally, where guideway lanes are placed beside 
each other along a common run, it is desirable that the lane spacing be 
minimized consistent with operating requirements because of construction 
and land costs. Once the lane spacing is defined, it is highly desirable 
that any guideway switches needed for lane switching be structured so that 
they can be located within the available lane space without requiring 
costly widening of the lane spacing around the switch locations. In the 
present case, the spacing between lane centerlines is 11 feet. 
Dotted guideways 24, 26, 28, and 30 represent planned future guideway 
additions. Various additional stations are provided for the guideways as 
indicated by the illustrated blocks with accompanying station names. 
In the present system configuration, right hand single turnout guideway 
switches 32 and 34, as well as a planned future left hand single turnout 
switch 35, are located near the Maintenance Building. A double turnout 
guideway switch 36 is also located nearest the Maintenance Building and 
two double turnout guideway switches 38 and 40 are located near the Caltex 
station. 
Guideway switches 42 and 44 provide a crossover between the lanes 12 and 20 
of a dual guideway. The crossover guideway switches 42 and 44 are right 
hand single turnout switches which provide the lane crossover routing 
without requiring widening of the specified guideway lane spacing. Use of 
transfer tables, pivotal switches and other prior art schemes would 
require lane widening for switch placement. 
GUIDEWAY CONFIGURATION 
The guideway configuration is illustrated in FIG. 1B by means of a 
cross-sectional view of the elevated guideway with a vehicle on it. FIG. 
1C shows the guideway configuration at a guideway switch location. 
Generally, the guideway can be structured so that the vehicle tire running 
surfaces are above or below or at ground level A vehicle 58 is provided 
with rubber tires 60 that propel the vehicle 58 when running vertically on 
surfaces 50 and 52. 
As shown, the guideway tire running surfaces 50 and 52 can be spaced 
surface portions running along the length of the surface of an elongated 
concrete guideway slab 54. In this case, it is preferred that the running 
surfaces be provided on pads 55 elongated in the longitudinal direction 
and extending slightly upwardly from the concrete guideway structural slab 
54. Cable troughs 162 and 164 are respectively provide outwardly of the 
tire running pads. Metallic covers 161 and 163 are provided for the 
troughs 162 and 164. If the vehicle should become disabled and stop at any 
point along the guideway, the surface of the cover 161 and the tire pad 
surface 50 together and the surface of the cover 163 and the pad tire 
surface 152 together form respective sidewalks for passenger use. 
A guidebeam 56 is supported by the slab 54 and extends along the slab 54 
midway between the running surfaces 50 and 52. The vehicle 58 carries 
guide wheels 62 and 64 having rubber tires that run horizontally along the 
guidebeam structure provided by successive guideway slabs to provide lane 
guidance for the vehicle 58. 
Electric rail structure runs along the length of the guideway slab and is 
supported above and to one side of each of the running surfaces Generally, 
the rail structure is configured to provide electric power for vehicle 
propulsion and electric signals for vehicle control. 
Specifically, rails 66, 68 and 70 carry power current for the vehicle 58 
and rails 72 and 74 carry central station control signals for directing 
vehicle operation on the guideway. 
In the preferred guideway configuration, the electric rail and guidebeam 
structure is located above and between the vehicle tire paths and it is 
organized to enable continuous current collection through continuous 
electric railing at guideway switch locations without mechanical on/off 
rail ramping of the car collector assemblies. By this location definition 
it is meant that the current collection surfaces on the electric rails and 
the guidance surface on the guidebeam are located above and between the 
tire surfaces. Normally most or all of the guidebeam and electric rail 
structure would thus be above the reference plane through the tire paths, 
but some portions of this structure may be located below the tire path 
reference plane so long as the current collection and guidance surfaces 
are located above this reference plane and between the tire paths. Current 
collection and guidance hardware on the underside of the vehicle can thus 
be designed to provided (1) specified ground clearance for the underside 
of the vehicle; (2) in conjunction with the rail structure, completely 
reversible vehicle operation on the guideway; and (3) in conjunction with 
the rail structure, continuous current collection through guideway switch 
locations without mechanical on/off rail ramping of the vehicle collector 
assemblies. 
Further, the running surface, electric rail and guidebeam structure is 
preferably symmetrically disposed on the two sides of the guideway lane 
centerline thereby enabling turnaround operation of vehicles on the 
guideway. By turnaround operation, it is meant that either end of the 
vehicle can be the leading vehicle end for vehicle travel over a guideway 
lane in either guideway direction with guidance and current collection 
functions being provided in both directions of vehicle travel. Generally, 
turnaround operation is enabled by the described symmetric disposition of 
electric rail and guidebeam structure and cooperative placement of 
guidewheel and collector assemblies on the underside of the vehicle. 
For more information on the background, functions and advantages of the 
illustrated guideway configuration, reference is made to the 
cross-referenced copending patent application Ser. No. 07/211,721. 
SINGLE TURNOUT ROTARY GUIDEWAY SWITCH 
A single turnout rotary guideway switch 100 (FIGS. 2A-2C) is arranged in 
accordance with the invention to provide for vehicle turnout from a main 
guideway lane to a turnout lane. 
In one rotary position referred to as the tangent rotary position, the 
upper side of the guideway switch 100 provides a guideway configuration 
(guideway, guidebeam, and rail structure) that keeps the vehicle in the 
lane in which it is moving When the guideway switch 100 is rotated, 
preferably through 180 degrees, the previous lower side of the guideway 
switch 100 becomes the upper switch side and it provides a guideway 
configuration that directs the vehicle from the lane in which it enters 
the switch (1) over a turnout path on the switch to a turnout lane or, 
alternatively, (2) over a crossover path to the other lane of a dual lane 
guideway In the latter case, the crossover path leads to another rotary 
guideway switch 100 located in the other lane and rotatively positioned to 
direct the vehicle onto the other lane. 
Generally, the rotary guideway switch 100 is structured to expose the 
vehicle as it moves through the switch 100 to a guideway cross-section 
that is essentially the same as that which exists elsewhere along the 
guideway Electrical contact with power and signal rails is continuous as 
the vehicle moves through the guideway switch 100 in either guideway 
switch position. 
Crossover on a dual lane guideway is achieved without requiring that normal 
guideway spacing be increased or bulged to permit guideway switch 
installation. Normally, the spacing of dual guideway lanes is made as 
small as possible to economize on land and construction costs without 
sacrificing safety, operational and aesthetic requirements. 
Further, as will become more evident hereinafter, self-aligning, failsafe 
operation of the rotary guideway switch 100 results where the weight of 
the vehicle load and the switch itself maintain the switch in its existing 
rotational position System safety is thereby significantly enhanced. 
Preferably, only one of the two guideway tire paths is provided on the 
tangent side of the switch frame 110. The substantial equivalent of one 
guideway path (i.e. a portion of each of the two tire paths that together 
substantially correspond to one path) is preferably provided on the 
turnout side of the switch frame 110. In this manner, the different 
guideway configurations required for the two different guideway switch 
positions can be provided with significant reduction in the switch load 
bearing requirements and in the switch weight and thus with significant 
economy and efficiency in switch design and operation. 
In end effect, the described "single tire path" structure is a key to 
providing a minimum weight for a movable section of the guideway while 
meeting switching requirements. Thus, the same guideway configuration 
found outside the rotary switch is essentially duplicated by the switch 
section in both switch positions through rotation of the described 
rotatable switch element 110 without requiring rotation of the entire 
guideway cross-section. 
The rotary guideway switch 100 is characterized with design flexibility 
especially since it is readily adaptable to meeting a variety of path 
switching needs. Among other benefits, its design flexibility additionally 
facilitates the development of switch designs for different radii of 
curvature specifications. 
There is shown in FIG. 2A a section of a guideway having the single turnout 
rotary guideway switch 100 in its tangent position Accordingly, a vehicle 
is guided over tire running surfaces 102 and 104A, 104B along a main lane 
106 as opposed to being switched onto turnout lane 108. 
The rotary guideway switch 100 comprises a rotatable and in this case 
generally rectangular frame member 110 that is supported in a switch pit 
112 (FIG. 2C) for rotation about longitudinal centerline 112C. Hydraulic 
and electric operating equipment is also housed in the pit 112 at opposite 
ends of the frame member 110. Generally, switching is achieved by a 
hydraulic actuator that rotates the movable frame 110 through 180 degrees 
about a longitudinal axis from one of its aligned positions to its other 
aligned position The switch is secured in either aligned position, 
preferably by four hydraulically actuated lock pins. More detail is 
presented subsequently herein on the switch operation. 
The main guideway has longitudinally extending outer housing walls 116 and 
118 within which the tire running surfaces 102 and 104A, 104B, guidebeam 
120A, 120B, and power and signal rails 122A, 122B and 124A, 124B are 
provided. The tire pad with its surface 102 is included as part of the 
fixed guideway structure. 
In the tangent switch position illustrated in FIG. 2A, the upper side of 
the guideway switch 100 is the tangent side which provides a tire running 
surface section 104SM (FIG. 2C) that connects main lane tire running 
surface 104A with main lane tire running surface 104B for continued main 
lane vehicle operation. A guidebeam section 120SM on the switch movable 
element 110 connects guidebeam 120A to guidebeam 120B to keep the vehicle 
on the main lane 106 as it passes through the switch movable element 110. 
Power and signal rail sections 122A, 122B and 124A, 124B similarly provide 
main lane interconnections for continuous main lane vehicle electrical 
contact. 
As shown in the cross-sectional view in FIG. 1C, horizontal guide wheels 
126 and 128 guide the vehicle over the guideway along the guidebeam 120, 
in this case the switch guidebeam section 120M. Electrically conductive 
brushes on the vehicle provide circuit continuity with the electrical rail 
sections 122SMA, 122SMB, 122SMC, 122SMG, and 124SMS as the vehicle moves 
through the guideway switch 100. 
In the turnout switch position illustrated in FIG. 2B, the guideway switch 
100 is rotated so that the lower or turnout side of the switch element 110 
in FIG. 2A becomes the upper side of the switch 100 in FIG. 2B. The 
turnout side of the switch 100 provides a tire running surface section 
102ST and a short section 104ST that respectively connect tire running 
surface 102A and 104A on the main lane 106 with tire running surface 102C 
and 104C on the turnout lane 108 for vehicle turnout operation. A 
guidebeam section 120ST on the switch element 116 connects guidebeam 120A 
to guidebeam 120C to provide vehicle turnout guidance as the vehicle 
passes through the guideway switch 100. Power and signal rail sections 
122C and 124C similarly provide connections for vehicle turnout operation 
(FIG. 2C). 
With main lane operation, the tire running surface 102 is on a pad that is 
part of the fixed guideway structure and the other tire running surface 
104 includes the switch tire running surface 104SM. When the guideway 
switch element 110 is rotated to its other position, the main lane tire 
running surfaces 102A and 104A are coupled to turnout lane tire running 
surfaces 102C and 104C by the respective switch tire running surfaces 
102ST and 104ST. Significant weight savings and size savings (i.e. radius 
of rotation) are thus achieved for the rotary guideway switch 100 thereby 
providing economy of switch manufacture and facilitated switch operation. 
Significant failsafe switch operation results from the fact that the 
vehicle weight always acts on the switch tire surface 104SM in the high 
speed main lane switch position to hold the switch element 110 in position 
against its safety stops even in the highly unlikely event that all lock 
pins would be in the unlocked position. 
In the lower vehicle speed turnout switch position of this single turnout 
embodiment of the invention, the vehicle weight similarly acts to provide 
lock pin backup over a substantial part of the length of the switch 
element 110. As will become more evident hereinafter, switch geometry is 
or can be arranged in various embodiments of the invention to enable 
complete backup protection through vehicle weight action. 
To provide protection against wrongful vehicle entry into a switch that is 
not aligned with the vehicle switch entry path, i.e. a switch aligned with 
the other guideway switch entry path, guide wheel stops are provided at 
the frog end of the switch. In FIG. 2A, stop 130 prevents a vehicle on 
turnout from entering from the frog end of the switch. In FIG. 2B, stop 
132 prevents a vehicle on the main lane from entering from the frog end of 
the switch. 
SINGLE TURNOUT - SWITCH AND EQUIPMENT LOCATION 
In FIG. 2C, the single turnout rotary guideway switch 100 is shown with 
more detail that highlights the location of various structural and 
equipment items. The switch 100 includes a rotatable frame, a pit for the 
frame, and other fixed components. The switch pit 112 is an elongated 
cavity located within the guideway structure to house the generally 
elongated rotary guideway switch 100 for rotation and to house the 
equipment and structure needed to drive and support the guideway switch 
100. Thus, the pit 112 is roughly subdivided into a main pit (31.5 feet 
long in this embodiment), a frog end equipment pit (4 feet long) and a 
point end equipment pit (4 feet long). 
The switch rotation occurs about longitudinal centerline 112C. In moving 
from the tangent position shown in FIG. 2C to the turnout position, the 
guideway switch 100 rotates in the clockwise direction about the 
centerline 112C as viewed from the left side of FIG. 2C. As previously 
considered, the tangent side of the switch 100 provides tire running 
surface and guidebeam and electrical rail structure appropriate to main 
lane routing. The turnout side of the switch 100 is appropriately 
configured for turnout routing. 
A fixed or frog end 140 of the guideway switch 100 is supported by a drive 
shaft 142 and lock pins 144 and 146. Pit space 113 is provided adjacent to 
the frog end 140 of the switch 100 to house electrohydraulic equipment 147 
that drives the frog end switch shaft 142 for switch rotation and operates 
the frog end lock pins 144 and 146. 
A fixed equipment frame 149 supports the drive shaft 142 and the lock pins 
144 and 146. The fixed equipment frame 149 additionally includes a 
rotation safety stop 157A (FIG. 4) that provides backup engagement with a 
movable switch frame 110 of the switch 100 in its main lane position, i.e. 
the position shown in FIG. 2C. The inserted lockpins provide the primary 
definition of the main lane switch position, and the backup stop 157A 
secondarily defines the main lane switch position in the event the 
lockpins 144 and 146 are unlocked for some reason. Thus, in the higher 
speed main lane switch position, vehicle weight is applied over the entire 
path of vehicle travel against the movable switch frame 110 always to 
force the switch frame to rotate toward the fixed frame stop 157A. As 
subsequently considered more fully, the rotary frame weight distribution 
also causes the switch frame 110 to rotate toward the stop 157A. 
A point or expansion end 148 of the guideway switch 100 is supported by a 
shaft 150 and lock pins 152 and 154. Another fixed equipment frame 153 
supports the shaft 150 and the lock pins 152 and 154. The frame 153 also 
supports electrohydraulic equipment 155 for operating the point end lock 
pins 152 and 154. 
The fixed equipment frame 153 also includes a rotation safety stop 157 that 
engages a switch frame portion as a backup for the switch 100 in its 
turnout position. The stop 157 thus secondarily defines the turnout 
position of the switch element 110, with the primary turnout position 
definition provided by the lockpins 152 and 154 when they are inserted 
into the switch element 110. If all of the switch lock pins are unlocked 
for some reason in this embodiment, the stop 157 acts as a backup support 
for the switch frame 110 in its turnout position during the portion of 
vehicle travel over the switch 100 when the vehicle weight and the switch 
frame weight urges the switch toward the fixed frame stop 157. 
The single turnout switch frame structure can be basically organized like 
the double turnout switch structure subsequently described herein to 
adjust the interface between the fixed structure tire path and switch tire 
path such that the switch tire path geometry enables the vehicle weight to 
push the switch against its turnout position stop over the entire switch 
tire path. In that case, continuous and complete backup rotation stop 
support is also provided in the turnout position of the single turnout 
switch. 
A switch logic cabinet 156 and a hydraulic unit 158 are located outside the 
guideway structure to provide for guideway switch control and operation. A 
control conduit 160C and hydraulic lines 160H are routed through the 
guideway concrete structure for connection to the electrohydraulic 
equipment 147 and 155. Cable troughs 162 and 164 are provided for routing 
system signal lines along the entire length of the guideway, and, as 
shown, the troughs can also be used to route the electrical and hydraulic 
lines 160C and 160H locally from one end of the pit 112 to the other pit 
end. 
To assure smoothness in the vehicle ride while providing more than adequate 
space tolerance for switch rotation, the spacing between each end of 
switch 100 and the adjacent fixed equipment frame 149 or 153 is preferably 
nominally 1/2 inch. Moreover, in constructing the guideway system, the 
equipment frames are secured in place with tolerances that assure 
placement of the rotary switch 100 such that its upper side configuration 
in either rotational position is in configuration alignment with the 
adjacent fixed guideway structure. 
FIGS. 3 and 3A-3P2 show various views of the guideway structure with the 
switch element 110, point end frame 153 and frog end frame 149 removed 
from the pit 112. The pit geometry and the way in which the switch 100 
fits in the pit 112 can thus be better perceived from these Figures. Some 
noteworthy aspects of the structure will be described. Reference 
characters used in connection with FIG. 2C have been applied to FIGS. 
3-3H, 3J-3N and 3P as appropriate. As indicated, this particular 
embodiment specifically applies to a right hand turnout switch having a 75 
foot radius of curvature. Centerline designations in the various views are 
as follows: TP means tire path; RF means rotation and foundation; and ML 
means main lane. 
As previously indicated, the tire path 102 on the main lane 106 is formed 
by fixed wall structure including path portion 102 which runs along one of 
the longitudinal sides of the pit 112. When the rotary guideway switch 100 
is in place in the pit 112 (FIG. 2C), one of the longitudinal sides of the 
switch 100 is disposed adjacently along the main lane path portion 102. 
For a vehicle entry at point end 172 (FIGS. 2C and 3) of the guideway 
switch 100, fixed main lane path portion 102A is continuous with the fixed 
tire path portion 170 along the main lane tire path 102. However, fixed 
main lane tire path portion 104A is interfaced with the rotary switch 
element 110 by means of a tread plate 178. Similarly, at vehicle exit 
(frog) end 173 of the guideway switch 100, main lane tire path portions 
102 and 102B are continuous. A tread plate 180 interfaces the switch tire 
running surface on either side of the rotary switch with main lane tire 
path portion 104B or turnout tire path 102C according to the rotational 
position of the guideway switch element 110. 
The frog end equipment frame is supported by pillasters 190 and 192. As 
shown in FIG. 3B, the pit is structured also to provide support for the 
tread plate 180. Similarly, pillasters 194 and 196 provide support for the 
point end equipment frame and the tread plate 178. 
As shown in FIGS. 3A and 3B, the floor of the pit 112 is sloped to provide 
for drainage through a drain 191. Alternate pit structures, elevated or at 
grade, may not have floors and would use standard structural steel shapes 
(e.g. I-beam) for primary members. 
The FIG. 3 series of sectional views highlight various structural features 
of the rotary switch pit 112. FIGS. 3A and 3B show the longitudinal sides 
of the pit 112 in elevation from the inside of the pit 112. FIGS. 3C-L 
show various pit elevational cross-sections that highlight the wall and 
pillaster structure for tread plate and equipment frame support. FIG. M1 
and 3M2 are sectional views of the frame 153 secured to the pilaster 194 
and accordingly provide additional perspective for this structure. FIGS. 
3N1-3P2 are details of plates 178 and 180. These detail views are similar 
to detail views considered more fully subsequently herein in connection 
with the crossover switch embodiment of the invention. 
SINGLE TURNOUT SWITCH-FRAME STRUCTURE AND SWITCH ASSEMBLY 
In FIG. 4, the tangent or main lane side of the single turnout rotary 
guideway switch rotating frame 110 is shown in a plan view. The basic 
structure of the switch 100 formed by a generally elongated structural 
frame member 110 comprising parallel longitudinal structural I beams 202 
and 204 and frog end, point end and center cross I beams 206, 208 and 210. 
From a strength standpoint, the switch framework is arranged to meet all 
structural and vehicular induced loads within tolerable bending and 
torsional stresses and specified maximum deflection. From an electrical 
standpoint, the switch is structured to provide power and signal rail 
continuity for a vehicle as it enters, passes through and exits the 
switch. 
Generally, the length of the frame 110 is based on the specified radius of 
curvature for the turnout path at the switching area. A greater radius of 
curvature requires a greater switch length. In this case, the switch 
length is approximately thirty-one feet. 
The width of the switch frame 110 is preferably less than the overall 
distance between the tire paths, but the frame width is sufficient to 
provide the necessary interface width of turnout guideway path on the 
turnout side of the switch 100 (with the main lane tire path fixed on the 
side opposite the turnout side). In this way, the rotary switch 100 can be 
structurally designed with economy for partial car loading as opposed to 
full car loading. Further, the weight of the rotary switch itself is 
limited and the rotational diameter of the rotary switch 100 is limited 
thereby enabling economy in the switch and guideway pit structure and 
facilitating the operation of the rotary switch 100. In particular, the 
relatively small size and weight of the switch rotating frame 110 produces 
efficiency allowing low operational horsepower requirements (less than two 
horsepower in this application). 
The switch frame width in this embodiment is such that the longitudinal 
beam 202 provides a tire path on the main lane side of the switch 100 for 
the tires on one side of the vehicle, and the longitudinal beam 204 is 
placed to lie just inside and below the fixed structure path (see FIG. 3) 
for the tires on the other side of the vehicle. Thus, only half of the 
vehicle weight is carried by the rotary switch frame 110 and its support 
structure in the main lane position. 
As in the present case, the rotary switch frame length can be great enough 
in relation to the vehicle length that a portion of a second vehicle 
connected to the first vehicle may be located on the rotary switch frame 
110 while the entire length of the first vehicle is on the switch frame 
110. In that case, the rotary switch frame 110 is designed to support one 
half of the total vehicle weight that can bear on the main lane side of 
the rotary switch frame, i.e. the portion of the weight of the full first 
vehicle translated through the vehicle tires on one side of the vehicle 
and the portion of the weight of the connected vehicle translated through 
the single vehicle tire located on the rotary switch frame 110. 
On its main lane side, the frame 110 is additionally provided with the main 
lane guidebeam section 120SM which is secured to the cross beams 206, 208, 
and 210. The power and signal rail structure is not shown in FIG. 4. 
A curved beam 212 provides cross frame support in the diagonal direction 
between the longitudinal beams 202 and 204 such that it provides the 
turnout tire running surface 102ST on the turnout side of the rotary 
switch 100 (the underside of the frame 110 as viewed in FIG. 4). For 
structural purposes, a bracing I-beam 214 provides similar cross frame 
support in the opposite diagonal direction, The curved turnout guidebeam 
section 120ST is also provided on the switch turnout side. 
Preferably, fiberglass grating is incorporated into the rotary switch frame 
to eliminate open areas between structural members and thereby facilitate 
maintenance and provide a secure stepping surface for passengers who may 
have to leave a vehicle that has had an emergency stop in the vicinity of 
a switch. Since the upper and lower sides of the switch frame are used for 
vehicle routing, the grating is installed to provide for loading on either 
side of the grating surface. Thus, the grating supports take loading in 
both directions. 
Rotational backup stop action is provided at opposite ends of the switch 
framework. As indicated by dotted lines in the upper left hand corner of 
FIG. 4, the safety stop 157A is a stop secured to the frog end fixed 
equipment frame 149 and is structured and positioned such that its top 
surface provides stop support, and preferably backup stop support, for the 
underside of corner portion of top plate of the longitudinal I beam 202 of 
the frame 110. 
Just prior to reaching the main lane stop position, the switch frame 110 is 
brought to a smooth stop in alignment for insertion of the primary frame 
supporting lock pins. The described stop structure acts as a backup 
support in the event lock pins fail to be inserted, i.e. the weight of the 
switch itself and any vehicle load pushes the switch frame a slight (less 
than 1/16") additional distance against the backup stop structure. 
To enable the switch frame 110 to rotate into the main lane position shown 
in FIG. 4, the bottom plate of the longitudinal I beam 202 of the frame 
110 is notched to remove its corner portion that would otherwise contact 
the frog end stop 157A and prevent the switch frame 110 from being rotated 
fully into its main lane position. 
As shown in the upper right hand corner of FIG. 4, a safety stop 157D is 
also preferably provided on the point end of the rotary switch. In this 
instance, the stop 157D is secured to the rotary frame and it has a 
projecting finger that engages a stop structure 157B on the point end 
fixed frame 153 if lockpin support fails in the illustrated main lane 
position. 
In the turnout position of the switch, the bottom surface of the frog end 
stop 157A similarly provides backup support for the inner surface 
(upwardly facing in the switch turnout position) of the abutting corner 
portion of the bottom (in turnout position) flange of the I beam 204. The 
opposite (top) flange of the I beam 204 is notched as indicated by 157E so 
that it can pass the stop 157A as the switch frame rotates into its 
turnout position. The point end stop structure 157C on the point end fixed 
frame 153 likewise provides backup support in the turnout position for 
frame stop structure 157D. 
Support structures for the frog end drive shaft 142 and the point end shaft 
150 are shown respectively in FIGS. 4A and 4B. 
As shown, the drive shaft 142 is supported relative to the fixed equipment 
frame 149 by means of a fixed tapered roller bearing assembly 216 on which 
the switch frame is rotated The tapered roller bearing assembly is a 
long-life, anti-friction unit that provides smooth operation and includes 
the following elements: 
218 pillow block and grease fitting 
220 bearing cone and bearing cup 
222 bearing seal 
224 seal retainer and gasket 
226 bearing sleeve 
228 screw 
230 lock washer 
232 locknut 
The point end shaft 150 is supported relative to the fixed equipment frame 
153 by means of another fixed tapered roller bearing assembly 234 on which 
the switch frame is rotated. As above, the tapered roller bearing assembly 
234 includes the following elements: 
236 pillow block and grease fitting 
238 bearing cone and bearing cup 
240 bearing seal 
242 seal retainer and gasket 
244 bearing sleeve 
246 screw 
248 lock washer 
250 locknut 
The two switch frame shafts 142 and 150 are respectively supported relative 
to the switch frame cross beams 206 and 208 by similar spherical bearing 
assemblies 251 and 253 which accordingly provide structural bearing for 
the switch frame. Each of the spherical bearing assemblies 251 and 253 
includes the following elements: 
255 spherical bearing supported on shaft 
257 bearing seat 
259 lock washer 
261 locknut 
A crankarm 263 is provided with the bearing assembly 251 and another 
crankarm 265 is provided with the bearing assembly 253. Each crank arm 263 
or 265 is secured to its shaft 142 or 150 and extends radially outwardly 
to a point where it has an end portion coupled to the switch frame cross 
beam 206 or 208. Accordingly, when the crank arm 263 (see the FIG. 5 
series) is driven by the shaft 142, it provides rotational drive force for 
the switch frame 110. The crank arm 265 similarly connects the passive 
point end shaft 150 and frame end beam 208 for coupled movement. While the 
point end crank arm 265 transmits no drive force to the switch frame 
because the point end shaft 150 is free to rotate, it does tie the frame 
movement to the movement of the point end shaft 150 so that point end 
shaft position can be used to confirm the frame point end position with 
the frame frog end position with use of a position detection device. 
The frog end bearing assembly 251 includes spacers 267 and 269 which fix 
the bearing 257 and the shaft 142 against relative movement in the axial 
direction. Thus, the frog end of the switch frame is fixed against 
movement in the longitudinal direction which could otherwise occur as a 
result of thermal expansion and contraction of the switch frame 110 or as 
a result of frame bending under vehicle load or vehicle braking or 
acceleration forces. 
At the point end of the frame 110, spacers like the spacers 267 and 269 are 
omitted thereby enabling the frame point end to undergo longitudinal 
movement under thermal or vehicle load. In the illustrated embodiment, 
space is provided for about 3/8 inch outward (rightward) or longitudinal 
frame movement due to thermal expansion whereas the expected maximum 
outward movement is 1/4 inch. As indicated by reference character 209, 
space is provided for about 1 inch inward (leftward) longitudinal frame 
movement due frame bending under vehicle load or due to thermal 
contraction or installation tolerances. 
FIGS. 4C and 4D show enlarged views of the frog end cross beam 206 for the 
guideway switch frame 110. The point end cross beam 208 is the same as the 
beam 206. 
As shown in the elevational view of FIG. 4C, the end beam 206 has 
respective seats 191 and 193 having openings 195 and 197 for receiving 
lock pins when the rotary switch frame 110 is rotated into either of its 
two guideway operation positions. As shown in the plan view having 
portions broken away (FIG. 4D), lock pin support is provided by a 
spherical bearing 199 or 201 which is provided with a retaining ring 203 
or 205 and a grease fitting 207 or 209. 
At a central location of the rotary frame end beam 206, the bearing seat is 
provided with an opening 221 for receiving the frog end drive shaft 142. 
The spherical bearing 255 provides shaft support. A retaining ring 215 and 
a grease fitting 217 are again provided for the bearing 255. 
To provide for switch frame rotation, the end beam 206 additionally has a 
seat 211 with an opening 223 for receiving the radially outward end of the 
crankarm 263 which is connected to the frog end drive shaft 142. A 
spherical bearing 225 supports the crankarm 263. Again, a retaining ring 
227 and a grease fitting 229 are provided for the bearing 225. 
The preferred shaft support arrangement for the switch frame 110 is a type 
of load support structure referred to as a Simple Supported Beam. 
The lockpins and rotating shaft are mounted on spherical seats located on a 
common reference line thereby freeing the framework to rotate about the 
center line as a hinge line under induced vehicle load. With hinge line 
rotation, translational forces to the hinge line are always vertical, and 
moments are distributed along the switch framework while essentially no 
bending moments are induced on the lockpins and shafts, i.e. the latter 
are significantly reduced in size compared to fixed end support (such as 
straight bore as opposed to spherical bearing receptacle). In effect, the 
switch frame carries vehicle load and transfers minimal bending moments to 
the supporting shafts and lockpins without frame leveraging that would 
otherwise cause high stresses on the shafts and lockpins. 
The hinge line is designated by the reference character 256F in FIG. 4 at 
the frog end and is best observed in FIG. 4A. A similar hinge line 256P 
operates at the point end of the frame, and it is best observed in FIG. 
4B. 
As a result of the operation of the preferred simple support structure for 
the switch frame support arrangement, vehicle load forces are transmitted 
through the frame hinge lines essentially as shear stress on the shafts 
and the lock pins. Otherwise, bending loads applied over the length of the 
switch frame would produce high tensile stresses on the shafts and locking 
pins thereby requiring excessively or impractically sized structures for 
these supporting elements. 
It is also significant that the described spherical bearing support 
structure provides a self-aligning feature permitting 180.degree. rotation 
of this switch frame 110 without binding against the shafts due to thermal 
distortion or due to manufacture to accuracy limitations. This 
self-alignment occurs since the spherical bearings can rotate relative to 
the switch frame. 
Preferably, the lock pin spherical bearings have extended rings that limit 
the extent of bearing rotation relative to the switch frame thereby 
assuring alignment conditions for lock pin insertion, to line up with 
centerlines of the frame support shafts. The lock pin spherical bearings 
similarly provide self-alignment since the bearings can rotate relative to 
the switch frame to permit lock pin alignment with the bearings when the 
switch is rotated into position for lock pin insertion. 
In a particular commercial embodiment, the framework was formed from A36 
steel employing both rolled and fabricated structural sections. The 
framework had a span of 31 feet 3 inches, a depth of 17 inches and a width 
of 6 feet 7 and 1/4 inches. To minimize the cumulative effects of fatigue, 
all connections except one were secured by high strength bolts. Maximum 
live load deflection at midspan was 1/4 inch. 
7. Solenoid RCV is de-energized removing pressure from the rotary actuator 
300 putting the unit in a free float position. 
8. When all lock pins are fully seated in the locked position, all 
solenoids and the motor contactor coil is de-energized. 
POWER AND SIGNAL RAIL STRUCTURE 
The power and signal rail structure is shown more clearly in the FIG. 5 
series of drawings. 
A perspective view of a typical guideway section is shown in FIG. 5 with 
the rail structure highlighted. In this case, a total of five electrical 
rails are needed and four of the rails are supported as a first rail unit 
447 that extends along the guideway structure just inside and just above 
the left tire path 104. The fifth rail is supported as a second rail unit 
449 that extends along the guideway structure just inside and just above 
the right tire path 102. The guidebeam 466 extends along the guideway 
midway between and parallel to the electrical rail units. 
The guidebeam and electric rail structure on the faces of the rotary 
guideway switch is symmetrically disposed about the guideway lane 
centerline so that the guideway switch is configured like the guideway to 
enable vehicle turnaround operation. The guidebeam is located along the 
lane centerline and thus is symmetric with reference to it. 
In addition, the two electric rail units are disposed on opposite sides of 
the lane centerline at equal distances from the lane centerline. 
Generally, a four-brush collector assembly is provided on each side of the 
vehicle undercarriage for current collection interface with the 
symmetrically disposed rail units. 
When the vehicle is travelling in one lane direction, one of the collector 
assemblies provides current collection through its four collector brushes 
from the four electric rails on the current collector four-rail unit 447, 
and the other collector assembly provides current collection through one 
of its four collector brushes from the one electric rail on the one rail 
unit 449. When the vehicle is turned around to move in the opposite lane 
direction, the interfacing of the vehicle collector assemblies with the 
rail units 447 and 449 is reversed. 
A three phase, Y-connected alternating current power system is employed to 
supply drive current to the vehicles on the guideway system. Rails 450, 
452, and 454 on the rail unit 447 (FIG. 5A) respectively operate as the A, 
B and C phase conductors. Alternate locations of the rails 450, 452 and 
454 are shown in phantom in FIG. 8AA only as 450A, 452A and 454A to 
illustrate another symmetric arrangement of the electric rails. Generally, 
the guideway length is divided into power blocks supplied by respective 
power sources (i.e. substations), and each power block is supplied by hard 
wires extending from the power source through the guideway cable troughs 
to the power block connection point. 
Typically, the full length of each power rail is formed by successive, 
practical length rail sections connected end-to-end. For example, each 
rail section could be thirty feet in length, and successive power rail 
sections within a power block are connected by conductive joiners (not 
shown). Successive rail sections at the boundary line between power blocks 
are connected by an isolation joiner (not shown). 
A two-conductor system is used to supply automatic train operation (ATO) 
signals to vehicles on the guideway. Rails 456 (on rail unit 447) and 458 
(on rail unit 449) operate as the two ATO conductors in each successive 
signal block along the length of the guideway. The signal blocks are 
normally different from and independent of the power blocks. 
In successive signal blocks, the function of the signal rail 456 is 
alternated from GND to ATO to GND, etc. Similarly, the function of the 
signal rail 458 is alternated from ATO to GND to ATO so that the functions 
of the two signal rails 456 and 458 are reversed from signal block to 
signal block. Therefore, successive thirty foot signal rail sections 
within a signal block are interconnected by conductive joiners, but at the 
boundary between successive signal blocks successive rail sections are 
interconnected by isolation joiners. The signal ground rail in each signal 
block is hard wired to ground. 
Each power and signal rail is provided with an elongated insulative cover 
460, and joints between successive cover lengths are bridged by insulative 
joint covers 462. Generally, the covers 460 provide insulation coverage 
for the entire rail conductive surface except for respective 
longitudinally extending vertical surfaces 451, 453, 455, 457, and 459 
which are exposed for contact by vehicle mounted electrical brushes. 
Each rail unit 447 or 449 is supported in place by power/signal rail mounts 
464 or signal rail mounts 463 which are suitably spaced along the length 
of the guideway. Each mount 464 is formed by an angle bracket 465 secured 
to the guideway structure (FIG. 5AA) and an insulative rail holder 467 
having a support arm for each rail. Each mount 463 has an angle bracket 
469 secured to the guideway structure and an insulative signal rail holder 
471. 
An enlarged bogey assembly view is shown in FIG. 5C to illustrate more 
clearly the power and signal connections between the electrical rails and 
the vehicle brushes. With respect to turnaround operation of a vehicle one 
of the vehicle collector assemblies interfaces with the rail unit 447 and 
has three of its brushes collecting power from the three power rails 450, 
452 and 454 and its fourth brush providing signal collection from the 
signal or ground rail 456 when the vehicle is travelling in one lane 
direction. In the opposite lane direction the same collector assembly has 
its three power collector brushes floating (inactive) and its fourth brush 
providing signal collection from the signal or ground rail 458 on the 
other rail unit 449. The other collector assembly operates in the same way 
but in reverse. 
An electrical interface is provided for the guideway electrical rails and 
the short electrical rail sections on the rotary guideway switch and the 
short electrical rail sections on any interface guideway structure that 
may be needed for switch installation (as in the case of a crossover 
switch installation described subsequently herein). Preferably, hard wire 
connections are made between the respective power and signal rails on the 
fixed guideway structure to the corresponding power and signal rail 
sections on the rotary switch. In addition, a hard ground wire is extended 
from a ground connection to the rotary switch for frame grounding. 
In FIG. 5D, there is shown a top plan view of the single turnout rotary 
guideway switch in its turnout position and with the power and signal rail 
structure highlighted. FIGS. 5A1, 5A2 and 5A3 show enlarged views of the 
electrical rail interfaces between the fixed and movable switch electrical 
rail structure in the turnout lane. FIG. 5E is like FIG. 5D but it shows 
the switch in its tangent or main lane position. FIG. 5A4 shows an 
enlarged typical view of the electronic interfaces between fixed and 
movable electric rail structure in the main lane position. 
To establish electrical continuity for the guideway switch, a total of six 
interconnection conductors couple the fixed guideway conductors to the 
rotatable switch conductors as follows: 3 power conductors, 4 shielded 
signal conductor pairs and a ground conductor. In addition, a separate 
pair of power conductors are included in the cable for connection to power 
and signal rails to provide rail heating. The 10 conductors are bundled 
together at the point end of the switch pit 112 as indicated by the 
reference character 473, and the bundle is extended through a suitably 
sized bore (such as 2.25 inches diameter) in the point end shaft 150 as 
indicated by the reference character 475. On the switch frame side of the 
point end shaft, the conductors are divided out of the bundle (see FIG. 
5E) and extended to the points where rail or frame connections are to be 
made. 
The inwardly facing bore surface is polished and the conductor bundle 473 
is preferably encased in a nylon wrapping (not indicated) and secured by 
end of shaft cable clamps so that the bundle 473 is free to flex 
substantially without abrasion. As the switch is rotated between its main 
lane and turnout positions, it moves through 180 degrees and the cable 
bundle 473 flexes through a corresponding twisting movement, i.e. 
preferably +/- 90 degrees over a five foot length. In tests, this 
interconnection scheme was found to be entirely satisfactory, i.e. no 
significant wear was produced on the bundle sheath after 40,000 switching 
operations. 
In applying the present invention, the design of commercial rotary guideway 
switches can incorporate relatively small gaps between each switch tire 
path and each longitudinally adjacent fixed guideway tire path. The gap 
size, for example, can be 1/4 inch which permits in excess of +/- 1/8 inch 
thermal expansion. Such small gap structure provides a foundation for two 
important benefits: (1) continuity in high speed power collection and (2) 
smoothness of vehicle ride. 
OVERVIEW - SWITCH OPERATION 
In the operation of the people mover system, each rotary guideway switch 
position is specified over the ATO circuit according to the path to be 
followed by vehicles moving in the system. Switch positions, sensed as 
previously noted, are checked against specified positions and any required 
changes are sent as switching commands over the ATO system. Wayside 
interlocking logic detects any guideway switch that fails to be positioned 
and locked as commanded and initiates safety car stoppage until the 
problem is corrected. If necessary, manual switch operation can be 
executed by operation of the hydraulic unit at the guideway switch 
location. 
At the guideway switch location, a switch position change is implemented by 
the following actions: 
1. The lock pin hydraulic actuators withdraw the switch frame lock pins. 
2. The lock pin position sensors verify the withdrawal of the lock pins. 
3. The rotary hydraulic actuator turns the drive shaft until the switch 
frame has moved from its previous position to its new position. 
4. The shaft position sensors verify the existence of the new switch frame 
position. 
5. The lock pin hydraulic actuators insert the lock pins into the switch 
frame. 
6. The lock pin position sensors verify the insertion of the lock pins. 
Total time for executing a switching operation is typically 10 seconds. 
When the rotary guideway switch is in the main lane position, vehicle 
loading forces the switch frame toward the stop structure in the main lane 
position. Safe operation thus occurs even if the lock pins have been 
withdrawn from the switch frame and not reinserted for some reason. 
Switch manufacture is significantly economized and switch operation is 
significantly facilitated by the fact that the switch structural strength 
and weight can be safely and relatively reduced because: 
1. Reduced vehicle loading results from structuring the rotary switch so 
that only those tires on one side of the vehicle, or the substantial 
equivalent thereof, can be on the guideway switch as the vehicle moves 
over the switch in either switch position. 
2. Reduced frame, lock pin and shaft strength requirements result from the 
hinge line, simple support arrangement. 
As previously indicated, significant savings in system construction costs 
and enhancement in system aesthetics are provided by avoidance of any 
requirement for guideway bulging at crossover switching locations. These 
advantages essentially result from the "single" tire path configuration of 
the rotary switch. 
From the standpoint of product strength, vertical loads induced in the 
switch frame are transmitted through the lock pins to the lock pin guide 
blocks on the equipment frames to the support pillasters. In the 
referenced commercial embodiment, the weight of the switch frame itself is 
16,500 lbs. 
Vehicle load is induced on the switch frame through the vehicle tires. In 
the commercial embodiment, load was specified at 7500 lbs. per tire with 
an axle spacing of 14.5 feet and with at most three; tires on the rotary 
switch frame. Maximum lateral loads due to guide tires was 3000 lbs. 
resulting in 3000 lbs. lateral load and an additional 1000 lbs. vertical 
load per main axle. To accommodate vehicle braking and acceleration on the 
switch frame, each equipment support was sized to take in excess of 9600 
lbs. longitudinal load. Overall, switch frame stiffness was employed to 
limit deflection to less than 1/4 inch in the tangent switch position and 
less than 1/8 inch in the turnout position at specified vehicle loading. 
Differential thermal expansions of concrete, steel, aluminum and rigid 
plastic also were reflected in the commercial rotary switch design. 
From the standpoint of safety, the following summary comments apply: 
1. The switch tends by its own weight to rotate into the closest alignment 
position against structural stops. 
2. In the high speed tangent position, the vehicle tires are only on one 
side of the switch frame to hold the switch against the stops even if the 
lock pins are unlocked. 
3. The lock pins are sized to be structurally redundant, i.e. four levels 
of switch support in addition to the support from the structural stops. 
4. Vehicle wrong entry stops keep the vehicle locked onto the guideway. 
5. Continuous power and signal rail through the switch eliminates vehicle 
speed restrictions often required with the use of guideway switches having 
mechanical on/off rail ramping.