U.S. patent number 3,851,594 [Application Number 05/362,012] was granted by the patent office on 1974-12-03 for electromagnetic suspension and guide system for suspended vehicles adapted to switch tracks.
This patent grant is currently assigned to Krauss-Maffei Aktiengesellschaft. Invention is credited to Peter Schwarzler, Christian Walkner.
United States Patent |
3,851,594 |
Schwarzler , et al. |
December 3, 1974 |
ELECTROMAGNETIC SUSPENSION AND GUIDE SYSTEM FOR SUSPENDED VEHICLES
ADAPTED TO SWITCH TRACKS
Abstract
An electromagnetic guide or suspension system for a magnetically
supported vehicle having at least two rows of electromagnets
extending along the vehicle in the direction of travel thereof and
cooperating with respective armature rails upon the supporting
track. Each row of electromagnets consists of two subrows of
electromagnets, the electromagnets of at least one subrow being in
a magnetic circuit with a respective armature rail at all times.
The rows of electromagnets are designed to receive armature rails
extending into the magnetic paths of the electromagnets
symmetrically from opposite sides so that the vehicle may travel
between a pair of outer armature rails along one track, can be
switched to a second track in which the armature rails are flanked
by the rows of electromagnets, or the electromagnets can be
disposed to the same side of the respective armature rails in an
asymmetrical arrangement.
Inventors: |
Schwarzler; Peter
(Furstenfeldbruck, DT), Walkner; Christian (Dachau,
DT) |
Assignee: |
Krauss-Maffei
Aktiengesellschaft (Munich, DT)
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Family
ID: |
5850077 |
Appl.
No.: |
05/362,012 |
Filed: |
May 21, 1973 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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324135 |
Jan 16, 1973 |
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Foreign Application Priority Data
Current U.S.
Class: |
104/130.02;
104/281 |
Current CPC
Class: |
B60L
13/003 (20130101); B61B 13/08 (20130101); B60L
13/04 (20130101); Y02T 30/00 (20130101); B60L
2200/26 (20130101); Y02T 30/30 (20130101) |
Current International
Class: |
B60L
13/04 (20060101); B60L 13/00 (20060101); B61B
13/08 (20060101); B61b 013/08 () |
Field of
Search: |
;104/148MS,130
;335/265,285,291 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Wood, Jr.; M. Henson
Assistant Examiner: Libman; George H.
Attorney, Agent or Firm: Ross; Karl F. Dubno; Herbert
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation-in-part of my co-pending
application Ser. No. 324,135, filed Jan. 16, 1973 and entitled
"Electromagnetic Suspension and Guide System for Vehicles Adapted
to Switch Tracks."
Claims
We claim:
1. In a suspended-vehicle system comprising a track and a vehicle
adapted to travel along said track and provided with
force-transmitting electromagnetic means between said vehicle and
said track, the improvement wherein said electromagnetic means
comprises at least two electromagnet arrangements extending along
and fixed to said vehicle, each of said electromagnet arrangements
including two subrows of electromagnets extending in the direction
of vehicle travel along said track; and armature rails mounted on
said track and cooperating with each of said electromagnet
arrangements respectively, the armature rail associated with each
electromagnet arrangement selectively entering the field of the
electromagnets of each subrow on different sides of a respectively
vertical plane through the electromagnet arrangement, each of the
electromagnets of each of said electromagnet arrangements being
paired with an electromagnet thereof in the other subrow, said
electromagnet arrangements being formed with energizing coils
common to the electromagnets of each pair.
2. The improvement defined in claim 1 wherein the electromagnet of
each pair comprises codirectionally extending U-profile magnetic
cores receiving the respective coil between the shanks thereof.
3. The improvement defined in claim 2 wherein said armature rails
are of U-cross-section and have shanks reaching toward the shanks
of said cores.
4. In a suspended-vehicle system comprising a track and a vehicle
adapted to travel along said track and provided with
force-transmitting electromagnetic means between said vehicle and
said track, the improvement wherein said electromagnetic means
comprises at least two electromagnet arrangements extending along
and fixed to said vehicle, each of said electromagnet arrangements
including two subrows of electromagnets extending in the direction
of vehicle travel along said track; and armature rails mounted on
said track and cooperating with each of said electromagnet
arrangements respectively, the armature rail associated with each
electromagnet arrangement selectively entering the field of the
electromagnets of each subrow on different sides of a respectively
vertical plane through the electromagnet arrangement, said
electromagnets having cores and coils, said armature rails and said
cores being of oppositely open U-section configuration with
respective shanks of the rails reaching toward the shanks of the
cores, said vehicle is provided with supports for said
electromagnet arrangements beyond horizontal planes defining the
outline of a vehicle body thereof, said supports including
uprights, said cores being disposed on horizontal lateral sides of
said uprights and being upwardly open, said coils extending around
said uprights.
5. The improvement defined in claim 2 wherein alternate cores along
each of said subrows are laterally offset from the other cores of
each subrow whereby energization of said coil provides a combined
vertical suspending and laterally guiding force between said
electromagnet arrangements and the respective rails.
6. In a suspended-vehicle system comprising a track and a vehicle
adapted to travel along said track and provided with
force-transmitting electromagnetic means between said vehicle and
said track, the improvement wherein said electromagnetic means
comprises at least two electromagnet arrangements extending along
and fixed to said vehicle, each of said electromagnet arrangements
including two subrows of electromagnets extending in the direction
of vehicle travel along said track; and armature rails mounted on
said track and cooperating with each of said electromagnet
arrangements respectively, the armature rail associated with each
electromagnet arrangement selectively entering the field of the
electromagnets of each subrow on different sides of a respectively
vertical plane through the electromagnet arrangement, said system
being provided with at least one branching region provided with
another armature rail associated with one of said electromagnet
arrangements and overlapping in the direction of travel of the
vehicle with the first-mentioned armature rail of said one of said
arrangements and reaching into magnetic cooperation with the other
electromagnet subrow thereof from that cooperating with said first
rail, the pole surfaces of the overlapping rails in said branching
region progressively receding from the electromagnets of the
respective subrows toward the ends of the overlapping rails.
7. In a suspended-vehicle system comprising a track and a vehicle
adapted to travel along said track and provided with
force-transmitting electromagnetic means between said vehicle and
said track, the improvement wherein said electromagnetic means
comprises at least two electromagnet arrangements extending along
and fixed to said vehicle, each of said electromagnet arrangements
including two subrows of electromagnets extending in the direction
of vehicle travel along said track; and armature rails mounted on
said track and cooperating with each of said electromagnet
arrangements respectively, the armature rail associated with each
electromagnet arrangement selectively entering the field of the
electromagnets of each subrow on different sides of a respectively
vertical plane through the electromagnet arrangement, said system
being provided with at least one branching region provided with
another armature rail associated with one of said electromagnet
arrangements and overlapping in the direction of travel of the
vehicle with the first-mentioned armature rail of said one of said
arrangements and reaching into magnetic cooperation with the other
electromagnet subrow thereof from that cooperating with said first
rail, each of the armature rails associated with said one of said
electromagnetic arrangements being provided in said region with a
respective coil excitable to counteract the flux of the
electromagnets of the respective subrow to maintain the magnetic
effectiveness of said one of said arrangements substantially
constant through said region.
8. In a suspended-vehicle system comprising a track and a vehicle
adapted to travel along said track and provided with
forcetransmitting electromagnetic means between said vehicle and
said track, the improvement wherein said electromagnetic means
comprises armature rails extending along and mounted on said track
and further comprises at least two electromagnet arrangements
extending along and fixed to said vehicle, each of said
electromagnet arrangements including two subrows of electromagnets
extending in the direction of vehicle travel along said track, each
of said armature rails normally cooperating magnetically with only
one of said subrows of electromagnets, the other one of the subrows
of each electromagnet arrangement cooperating magnetically with an
overlapping one of said armature rails at a branching.
Description
This application is also related to the commonly assigned
co-pending applications:
Ser. No. 268,132, filed June 30, 1972 and entitled "Electromagnetic
Suspension and Guide System for Magnetically Suspended Vehicles,"
(now U.S. Pat. No. 3,804,022).
Ser. No. 268,133 filed June 30, 1972 and entitled "Electromagnetic
Suspension and Drive Means," (now U.S. Pat. No. 3,797,403)
Ser. No. 280,073 filed Aug. 11, 1972 and entitled "Electromagnetic
Suspension and/or Guide System, Especially For Magnetically
Suspended Vehicles," (now U.S. Pat. No. 3,780,668), and
Ser. No. 292,638, filed Sept. 27, 1972, and entitled "Contact
System for High-Speed Electrically Operated Vehicles," (now U.S.
Pat. No. 3,804,997).
FIELD OF THE INVENTION
The present invention relates to an electromagnetic suspension
and/or guide system for magnetically supported vehicles and, more
particularly, to a construction of such magnetic suspension and/or
guide means as will facilitate transfer of the vehicle between
tracks, i.e., the switching of the vehicle from one track to
another.
BACKGROUND OF THE INVENTION
Conventional rail systems of the type used heretofore for
transportation of passengers and freight have hitherto been limited
by the frictional interaction of the supporting track structure and
the vehicle. In such systems, the vehicle is carried by wheels or
the like on a track by rails or other substantially continuous
supporting surface upon which the wheel bears with rolling friction
under the distributed weight of the vehicle and load. The rolling
friction increases with load and becomes increasingly significant
as vehicle speed increases, not only because of the power loss, but
because of the frictional limitations such rolling systems imply.
With increasing interest in high-speed vehicles for interurban,
intraurban and rural-urban transport of the passengers and freight,
considerable attention has been directed to reducing the frictional
forces which have hitherto limited high-speed rail travel as
described above.
In general, two approaches have been taken toward limiting
frictional engagement of the vehicle with the supporting track. One
involves the use of a fluid cushion (air cushion) between the
vehicle and track while the other has involved suspending the
vehicle electromagnetically from a track or other substantially
continuous support. For this purpose, the vehicle is provided with
an electromagnetic arrangement whose cores are juxtaposed with an
armature rail along the track to maintain a suspension gap spanned
by a magnetic field.
A typical construction of this type makes use of a T-shaped track
having a pair of armature rails disposed along the undersides of
the crossbar and juxtaposed with rows of electromagnets on the
aprons of the vehicle underhanging the rails. In another
construction, the T-shaped track is provided with armature rails
along the upper surfaces of the crossbar and electromagnets of the
vehicle are juxtaposed with these rails.
Because in such systems the track is always disposed centrally of
the vehicle and generally is flanked by aprons thereof, it has been
difficult, if not impossible, to effect transfer of the vehicle
from one track portion to another, i.e., to carry out switching of
the vehicle. For example, a switching of the vehicle is possible
with earlier systems specifically described above, and others of
similar construction, only by swinging a portion of the track from
alignment with one right-of-way to alignment with another
right-of-way, i.e., by mechanically displacing a portion of the
track. The switching of the vehicle from one track portion to
another, at spurs or crossovers, has not been possible in most
instances with earlier magnetically suspended vehicles using a
T-profile support track of the character described.
OBJECTS OF THE INVENTION
It is the principal object of the present invention to provide an
improved magnetic suspension and/or guide system, especially for
high-speed vehicles, which is adapted to permit transfer of the
vehicle from one track system or branch to another track system or
branch without the disadvantages of the arrangements mentioned
earlier.
Another object of the invention is to facilitate switching of a
magnetically suspended and/or guided vehicle without swinging or
other mechanical displacement of a portion of the supporting
track.
Yet another object of the invention is to increase the versatility
of magnetic suspension and/or guide systems for suspended vehicles.
Still another object of the invention is to improve upon the
systems described in the co-pending application Ser. No. 324,135,
filed Jan. 16, 1973 identified earlier.
SUMMARY OF THE INVENTION
As described in the co-pending application Ser. No. 324,135, filed
Jan. 16, 1973 these objects and others which will become apparent
hereinafter are attained, in accordance with the invention, by
providing a vehicle and track system with electromagnetic
suspension and/or guide means which comprises two rows of
electromagnets on the vehicle, each electromagnet consisting of a
core and an electromagnetic coil wound upon this core, whereby at
last the cores are of such configuration that substantially
symmetrical and equivalent electromagnetic paths are adapted to be
closed therewith by armature rails approaching the electromagnets
selectively from either side. Each row is made up of a number of
electromagnets disposed one behind another in the direction of
displacement of the vehicle and is designed to cooperate with one
of the two rails essential for supporting or guiding the vehicle.
The two rows of electromagnets preferably are disposed
symmetrically to one another (mirror symmetry) with respect to a
vertical median plane through the vehicle in the direction of
travel thereof. The electromagnets thus lie in a common horizontal
plane, with each row of electromagnets being symmetrical about a
respective vertical median plane of symmetry extending in the
direction of vehicle travel and through the respective row. Each of
these last-mentioned planes thus is a symmetry plane for the core
of the respective electromagnets.
The cores are preferably open in opposite horizontal directions (in
accordance with the principles of the above-identified earlier
application of which this case is a continuation in part) to
accomodate armature rails from either side, at least part of each
armature rail being adapted to reach laterally into magnetic
cooperation with the core of the associated electromagnets. With
this arrangement, each of the electromagnets can cooperate with an
armature rail juxtaposed therewith from the right or left side such
that the rail can be brought exclusively laterally into the
magnetic path and withdrawn therefrom in the lateral direction.
The electromagnets, in this case, are so disposed that they are
mounted on supports or pedestals of the vehicle extending
vertically therefrom beyond the horizontal planes defining the
upper and lower portions of the vehicle body, the pedestals being
spaced apart to accommodate a central track member between them or
being adapted to be flanked by a pair of track members, depending
upon the track configuration. In other words, the track along which
the vehicle travels may either have a central support member
flanked by two rows of electromagnets and provided with outwardly
facing armature rails adapted to project into the inner
electromagnet paths of the two rows, or a channel configuration
with a pair of armature rails flanking the outer poles of the
electromagnets and adapted to enter laterally inwardly into
magnetic paths thereof. It will be immediately apparent that
switchover from one track system to another track system is readily
accommodated when, at least in the transition region, the vehicle
passes from a channel-like portion to a central portion or vice
versa.
The versatility of the system is further increased by the fact that
an asymmetric arrangement of the track may be provided with, for
example, one armature rail (mounted upon a respective track
portion) engaging one electromagnet row from the exterior and
another armature rail engaging the other electromagnet row from the
interior. In this case, both armature rail arrangements are
disposed at the same side, i.e., either the right side or the left
side, of the two rows of electromagnets to facilitate the branching
of the vehicle path to the respective side. Each row of
electromagnets may comprise a single row (according to the system
of the last-mentioned co-pending application) with the cores in
mirror-symmetrical relationship with respect to its vertical plane
and in mirror symmetrical relationship with the cores of other rows
with respect to the vertical median plane through the vehicle body.
The armature rails can then include a respective armature rail
which can engage the electromagnets from either side, each row of
electromagnets being associated with at least one armature rail so
that two armature rails always cooperate to support and guide the
vehicle. The electromagnet cores have double-T configurations with
a vertical shank or web so that the magnetic circuit generated by
the coil upon this shank or web can be closed over the flanges of
the double-T to the left or to the right respectively upon
juxtaposition with the respective armature rail.
The system described in the last-mentioned application also
includes an armature rail of U-shaped profile or cross section
which is attached by its base to a vertical flank of a support
beam, the beam being part of a channel or central support
structure. In a channel-shaped support structure, a pair of beams
extend in the direction of vehicle travel, are horizontally spaced
parallel to one another and have vertical flanges each carrying one
armature rail so that the flanges or arms of these rails project
symmetrically toward one another and toward a vertical median plane
of the vehicle traveling between the beams. In the central-support
configuration, the beams at least in part are straddled by the
vehicle and lie in a vertical median plane thereof so that opposite
faces of the beam carry the armature rails and the flanges of the
latter extend outwardly. The flanges, or at least one flange, of
each of these armature rails is provided with an edge portion which
is turned preferably downwardly to lie in a vertical plane and is
adapted to confront a pole piece of the core of an electromagnet
carried by the vehicle. Each armature rail defines with the
horizontally projecting flanges or pole pieces of the cores of a
corresponding row of electromagnets, a pair of air gaps located one
above the other in a common vertical plane. With such armature
rails, especially when the system does not make use of separate
guide magnets (to center the vehicle laterally), the flanges of the
electromagnet cores are formed with upwardly turned pole pieces at
their free ends for juxtaposition with downwardly turned pole
pieces of the armature rail. In some cases it is desirable to
reduce the magnetic resistance of the magnetic circuit formed by
the air gaps, the core and the armature rail by forming one of the
flanges of the armature rail and the juxtaposed flange of the core
with flat surfaces free from inwardly turned pole pieces and in
laterally overlapping relationship.
The force components tending to maintain the vehicle in normal
position during vehicle travel can be increased, even to the extent
that separate guide electromagnets can be omitted, by constructing
the row of centering suspending electromagnets cooperating with
each armature rail with two sets of pole pieces flanking each pole
piece of the armature rail. The pole pieces preferably alternate to
opposite sides of the pole pieces of the armature rail by
horizontal staggering of identical symmetrical electromagnet cores
from side to side along the row, by horizontal staggering of the
webs of electromagnets having asymmetrical flanged cores from side
to side, by aligning the latter webs when each electromagnet is
oriented with the longer flange of an asymmetrical core in the
direction opposite the direction to which the longer flange of
adjacent electromagnets extend, or by providing the alternate
electromagnets with longer and shorter horizontal flanges.
When a guide system separate from or in addition to the suspension
system is required to counteract horizontal force components, e.g.,
as produced by wind or centrifugal force (the latter during the
turning of the vehicle), the coils of the guide-electromagnet
system may be of a lesser height than those of the suspension
electromagnets but may also be wound upon double-T horizontal
flanges which can receive between them a pole piece of one flange
of the armature rail so that the remainder of the armature rail is
free from magnetic fields produced by the guide electromagnets.
This system is particularly satisfactory for central arrangements
of the armature rails.
As has also been disclosed initially in the last-mentioned
co-pending application Ser. No. 324,135, filed Jan. 16, 1973, means
is provided at least at the branches or junctions of the track to
annul or partially annul the fields in selected rails so that, for
example, when the vehicle encounters a junction at which additional
rails come into play, the flux produced by the vehicle-borne
electromagnets is reduced and a magnetic shock is not applied to
the vehicle. In the absence of such means for maintaining the net
force upon the vehicle substantially constant as it traverses the
junction, the vehicle would encounter increased force fields and
would be subjected to sudden reduction in applied magnetic force as
rails terminate. The last-mentioned means may include coils wound
upon one of the shanks of each armature rail and can be controlled
by air-gap sensors or other inductive sensing means juxtaposed with
the armature rails and adapted to respond to the juxtaposition of
the vehicle electromagnets therewith. Manual means can, of course,
also be provided, either under the control of a vehicle operator or
the operator of the switch junction. The same field-annulling means
may be used to induce the vehicle to travel along the selected
track.
According to the present invention, the aforementioned system is
improved by forming each of the rows of electromagnets mounted on
the vehicle and extending in the direction of vehicle travel, with
two subrows of laterally paired and substantially adjacent
electromagnetic members, each of which is designed to cooperate
with a respective armature rail reaching into the magnetic field of
the respective subrow. At least one subrow of each longitudinal
electromagnetic arrangement or main row is in a state of magnetic
interaction with an armature rail at all times during vehicle
travel over the track net-work, i.e., as the vehicle negotiates
ordinary lengths of track, junctions, crossovers and branching
locations.
According to a more specific feature of the present invention, a
pair of electromagnet members in laterally adjacent relationship,
including one of each subrow, are provided with a common energizing
coil. While the use of two subrows of electromagnet members or
cores may increase the total weight of the electromagnetic
arrangements extending longitudinally in two main rows along the
vehicle, this has not been found to be a technological disadvantage
since even the electromagnetic cores described in connection with
the double-T configuration must have four available pole pieces or
flanges and the subdivision of the electromagnets, so that two
distinct cores are provided, generally decreases the fabrication
and mounting cost and enables the electromagnet members to have
simplified configurations. Since a pair of magnetic members or
cores is energized by a common electromagnet coil, the weight and
cost of the coils of the present system can be relatively low and
the use of the suspending magnet arrangement for providing lateral
centering forces is facilitated.
According to another feature of the present invention, the
successive electromagnet members or cores of each subrow are
laterally staggered and have U profiles, while the armature rail
adapted to be juxtaposed with each subrow is a U-profile rail whose
flanges or pole pieces reach downwardly to lie normally in vertical
planes to opposite sides of which the upwardly directed pole pieces
or flanges of the electromagnet cores are symmetrically and
alternately staggered. The electromagnet coils preferably link
pairs of cores to the same side of the armature rails so that all
of the coils associated with the cores to one side can be connected
to a common control circuit while all of the coils of the cores
offset to the opposite side are connected to a second control
circuit. The circuits are individually regulatable to adjust the
lateral force components and maintain a centered position of the
vehicle.
The U configuration of the armature rails and the electromagnetic
cores permits the armature rail and the cores to approach to one
another and separate from one another at junctions or the like in
the vertical direction and in a gradual manner, thereby
progressively increasing or decreasing the magnetic resistance
between each rail and the associated subrow of cores. To this end,
we provide that, at least at junctions at which a transfer of the
electromagnetic effectiveness is to be carried out from one
armature rail cooperating with one subrow to an armature rail
cooperating with the other subrow of each electromagnet
arrangement, the two rails overlap in the direction of the vehicle
travel and are inclined with respect to the path of the
electromagnet arrangement such that one rail progressively
approaches this path while the other rail progressively recedes
from this path so that the net magnetic force of the electromagnet
arrangement remains constant. This can be accomplished, according
to the invention, by tapering the armature rails and/or by mounting
the armature rails (which may be of constant cross section) upon
inclined supports. Of course the magnetic force through part of the
armature rail may be annulled by the use of electrically excitable
coils as described earlier. The vehicle may be driven by a linear
induction motor as described in the copending application Ser. No.
324,150, filed Jan. 16, 1973, entitled "Two-Sided Linear Induction
Motor Especially For Suspended Vehicles."
The overlapping-rail arrangement, structured to avoid any intense
increase or diminution in the overall magnetic resistance
encountered by each longitudinally extending electromagnetic
arrangement and hence without the expected doubling of the magnetic
force because of the doubling of the number of rail which are
effective, effectively prevents the application of magnetic shock
to the vehicle.
At crossovers, branches and switch junctions, the rail
configuration is provided in such a manner that at least in the
direction to which the vehicle is branched, two armature rails
asymmetrically support the vehicle, i.e., are effective to the same
side of the respective electromagnetic arrangements until the
junction is passed, whereupon a symmetrical disposition of the
rails is provided. In this manner, the switch junction does not
require any moving parts.
DESCRIPTION OF THE DRAWING
The above and other objects, features and advantages of the present
invention will become more readily apparent from the following
description, reference being made to the accompanying drawing in
which:
FIG. 1 is a diagrammatic vertical cross-section through a vehicle
and track system, embodying the present invention, using a pair of
outer track members and showing an inner track member in dot-dash
lines, the vehicle outline being likewise shown in dot-dash
lines;
FIG. 2 is a cross-sectional view, drawn to a somewhat larger scale,
taken along the line II--II of FIG. 1;
FIG. 3 is a perspective sectional end view of a portion of a track
according to one embodiment of the present invention; FIG. 3A is an
end section showing the profile of an armature rail for this latter
track;
FIG. 4 is a view similar to FIG. 3 showing a section of a track
according to another embodiment of the invention; FIG. 4A is an end
section showing the profile of of an armature rail for this latter
track;
FIG. 5 is a plan view showing a junction between a channel-shaped
track and a channel-shaped spur, in which the transition between
the main track section and the spur is effected by means of central
track members;
FIG. 6 is a plan view of the junction between a straight track
section of the central type and a central spur track with the
transition at the junction being effected by means of
channel-shaped tracks;
FIG. 7 is a vertical section similar to FIG. 1 but taken generally
along the line VII--VII of FIG. 5;
FIG. 8a is a vertical section showing an embodiment of an armature
rail provided with a coil according to the invention; and
FIG. 8b is a section similar to FIG. 8a but illustrating another
embodiment of the invention.
SPECIFIC DESCRIPTION
In FIG. 1, there is shown a vehicle 1 which has been outlined in
dot-dash lines and may have the configuration of any of the
magnetically supported vehicles described in the aforementioned
copending applications. The vehicle 1, which may be powered by a
linear induction motor or any other propelling source, may have its
electrical systems energized by wipers engaging current-carrying
rail mounted upon the track but not illustrated here to avoid
confusion. Such wiper arrangements are disclosed in the
aforementioned copending application, Ser. No. 292,638.
The vehicle 1 is provided along its underside with two T-profile
supports or pedestals 2, 3 running generally in the direction of
vehicle travel (perpendicular to the plane of the paper in FIG. 1)
symmetrically disposed on opposite sides of a vertical median plane
P.sub.1 of the vehicle extending in the direction of travel. The
direction of travel is represented by the arrow T, in FIG. 2.
Each of the pedestals 2, 3 carries a respective electromagnet
arrangement shown generally at 4 and 5, corresponding to a row of
electromagnets, each row being subdivided into two subrows 6, 7,
and 8, 9 respectively of controlled electromagnets individually
designated at 6', 7' and 8', 9' respectively. As noted earlier, all
of the electromagnets of each subrow can be connected to a common
control as diagrammatically illustrated for the control circuits
C.sub.1 and C.sub.2, respectively, in FIG. 2. Control circuits of
this type, designed to center the vehicle along the track and
maintain a constant suspension gap, may include sensors responsive
to the gap spacing (distance between electromagnet core and
armature rail) as described in the aforementioned copending
applications. The electromagnets 6', 7', 8', 9' cooperate with
respective armature rails which may be effective at the left or
right hand side of each magnet, selectively, as will be described
in greater detail hereinafter.
The vehicle is thus magnetically suspended from a pair of armature
rails 10 and 11, carried by the track which is generally
represented at 12 and can either be of the channel or central type
or a hybrid of both. In a channel configuration of the track, the
pedestals 2, 3 are received between the track beams or members
whereas, with a central configuration, a track beam is received
between these pedestals. In the embodiment illustrated in FIG. 1,
moreover, the electromagnets provided along the upwardly turned
faces of a pair of transverse flanges of the pedestals, which
flanges constitute the cross bar of the T.
Armature rails 10 and 11, of magnetically attractable material,
e.g., iron, are here shown to be fastened upon the undersides of
inwardly extending transverse flanges 13' and 14', respectively, of
a pair of beams 13 and 14 extending along the right of way of the
track and supported at intervals by pylons 13" and 14"
respectively. The armature rails 10 and 11 close respective
magnetic circuits with the left hand portions of the electromagnets
6' and 7' of subrows 6 and 7 and with the right hand sides of
electromagnets 8', 9' of subrows 8 and 9, across the usual
suspension gap spanned by a magnetic field generated by the
electromagnets.
The electromagnets can also cooperate with armature rails,
represented at 16 and 17, of a central track portion 25 consisting
of a T-section beam 15 supported at intervals by pylons 15'. The
central track thus may have a pair of outwardly extending lateral
flanges 15a and 15b whose downwardly-turned undersides carry the
armature rails 16 and 17. The inner armature rails can cooperate
with both inner magnet rows 7, 8 of the electromagnet arrangements
4, 5, respectively, as illustrated in dot-dash lines in FIG. 1.
Each of the electromagnets of the magnetically suspended vehicle 1
comprises a longitudinally extending core 18 of substantially
U-cross-section whose interior space along a coil side 19' receives
a coil 19 filling the space. The lateral shanks 20 and 21 of each
core form pole pieces reach upwardly toward the armature rail 10 or
11 of the track 12. The second coil space 19" is also filled with
the coil 19 but, as shown in FIG. 2, lies on the opposite side of
the pedestal 2 to form a member of the second row of
electromagnets. In other words, each coil cooperates with the two
cores (a pair of corresponding cores), each having a pair of pole
pieces and lying on the opposite side of a vertical plane P.sub.2
from the other electromagnetic core energized by the same
electromagnet. Each coil thus functions to excite two distinct
electromagnets, one from each of the subrows of a given
electromagnet arrangement. Each energizing coil 19 thus induces a
magnet field in a pair of electromagnet coils 6' and 7' or 8' and
9', at least one core of each electromagnet coil closing a magnetic
field through a respective armature rail in maintaining the
electromagnet suspension. Since the two cores on opposite sides of
each plane P.sub.2 is substantially identical to the other and is
energized by the same coil, it does not matter which of the two
cores is juxtaposed with an armature rail and transfer of the
magnetic effect from one armature rail on one side to an armature
rail on the other side can be accomplished with ease. The
electromagnetic arrangement each may operate with rails on either
side so that transfer of the vehicle between one track and another
is simplified.
FIGS. 1 and 2 also show that each of the electromagnet cores of
each row (6 or 7) is offset laterally with respect to the next core
along the row so that, for example, one core 6' lies to the left
while the next core 6' of an adjacent electromagnet in each
direction lies relatively to the right with reference to a plane
P.sub.3 representing the preferred position of a pole piece of an
armature rail with which the cores 6' cooperate. Another plane
P.sub.4 defines the normal position of the other pole piece of the
same rail, e.g., the rail 10 shown in FIG. 1.
Since the cores 7' associated with each core 6', are similarly
offset, each subrow of electromagnets consists of a succession of
mutually staggered cores which are located alternately on opposite
sides of a respective pole piece of the armature rail so that a
selfcentering or selfguiding system is provided to resist lateral
force components upon the vehicle. Such lateral force components
arise as a result of centrifugal force when the vehicle negotiates
the curve, or from the action of wind upon the vehicle. Each
electromagnet shank to the left of a pole piece exerts an
attractive force with a vertical component (contributing to the
vehicle-suspension force) and a leftward horizontal component which
may be increased or decreased by increasing or decreasing the
amplitude of the electrocurrent traversing its coil. Conversely
each core pole piece to the right of the armature pole piece exerts
an attractive magnetic force, in addition to its vertical
component, with a rightward horizontal component proportional to
the amplitude of the energization current through its coil.
Normally the magnetic force components to one side are balanced by
the force components to the other side and the vehicle rides along
a path such that each of the armature rails have pole pieces
secured between the pole pieces alternately straddling it.
When the vehicle encounters a lateral force in one direction, the
corresponding lateral force component may be reduced and the
opposing lateral force component increased by controlling the coil
excitation current to restore equilibrium to the vehicle in the
proper position. It has been found to be desirable to operate all
of the electromagnets which produce a leftward lateral force
component with one circuit and all of the electromagnets which
control the rightward force component with another circuit as has
been illustrated for the circuits C.sub.1 and C.sub.2 of FIG.
2.
Preferably, the armature rails 10, 11 or 16, 17 of the track
generally represented at 12 have an U-profile cross-section with
the pole pieces 22 having a thickness and spacing equal to the
thickness and spacing of the shanks or pole pieces 20 and 21 of the
electromagnet cores 18.
The armature rails are mounted at their bases or webs upon the
beams 13, 14 and 15 of the track so that their lateral shanks lie
in vertical planes (e.g., in the direction of travel of the
vehicle). The pole pieces of the cores 18 and of the armature rails
10, 11, 16 and 17 are thus vertically spaced by airgaps which are
spanned by attractive magnetic fields. The two airgaps of each
magnetic circuit are here horizontally spaced apart.
It has been found to be advantageous to maintain the suspension
airgaps constant by providing gap sensors, here represented
generally at 23, adapted to feed signals representing the actual
gap spacing into the control circuits C.sub.1 and C.sub.2,
respectively, for comparison with set-point signals introduced at
S.sub.1 and S.sub.2, respectively, to vary the amplitude of the
current traversing the coils. It has also been found to be
advantageous, as shown in FIG. 2, to locate the gap sensors 23
between the individual magnets of each subrow directly in the
respective plane P.sub.3 or P.sub.4 of the center of the pole piece
22 of the armature rail in its normal position. While any gap
sensor arrangement may be used (capacitive, inductive or optical),
it is preferred to make use of inductive gap sensors as described
in the aforementioned copending applications.
As has been described above, both armature rails, during normal
travel of the vehicle along the track, mirror-symmetrically
cooperate with the electromagnetic arrangements of the vehicle,
i.e., both from the outside or both from the inside, to suspend the
vehicle via the outer rows of magnets 6, 9 or the inner rows of
magnets 7, 8. At switching locations, there are provided transition
rails (FIGS. 5 and 6) of the other type so that the vehicle can be
directed to one side or the other. Preferably, where a switch
junction is provided for a channel-shaped track configuration, each
of the armature rails continues through the junction, one rail
maintaining its original orientation while the other is diverted to
form one rail of a spur track. In the region in which the two
armature rails diverge, there are provided central armature rails
which become effective to support the vehicle as the ordinary
traffic rails become inaffective. In a switch-type junction between
tracks of a central configuration, it is necessary to terminate at
least one of the rails of at least one one of the branches at the
junction and, in the region of such termination, at least one outer
armature rail is provided to take up the magnetic support via the
magnetic arrangement of the armature rail which was rendered
ineffective.
In general, switching regions and junctions require certain
armature rails to become ineffective with respect to the suspension
function and in these regions there are provided suspension rails
of the other type (i.e., inner-suspension rails where the outer
rails become ineffective and outer-suspension rails where the inner
rails become ineffective) so that the previously effective subrow
of electromagnets transfers the suspension function to the
complementary subrow of each electromagnet arrangement.
At the beginning and end of each armature rail at such a junction,
therefore, there can be provided a complementary armature rail in
overlapping configuration in the direction of travel of the
vehicle. The term "complementary" is used herein to refer to an
inner rail and an outer rail pair for cooperation with a given
electromagnet arrangement and, therefore, with the two subrows
thereof. The term "overlapping" is used herein to indicate that the
complementary rail should begin before the other rail of the
complementary pair ends so that, at least in the junction region
both rails of a complementary pair cooperate with a respective
electromagnet arrangement at the junctions.
The beginning of one armature rail can coincide with the end of
another (of a common principal row of electromagnets or
electromagnet arrangements) whose levitation function is to be
eliminated and transferred to the first armature rail with
reference to the direction of movement of the vehicle or car. In
other words, where it is desired to terminate the suspending force
along the outside of an electromagnet arrangement and commence
application of the suspending force to the inside thereof, or vice
versa, one rail of each confunctional pair eventually must be
rendered ineffective (transfer or rail) while the other rail of the
pair is rendered effective (transferee rail). In a coincidental
termination system, the transferee rail is encountered precisely at
the instant at which the transferor rail terminates with respect to
any point on the vehicle.
With this construction, wherein beginnings and ends of the contact
rail pairs 10, 16 or 11, 17 associated with each electromagnetic
row coincide, one would normally expect a substantial magnet force
shock from instantaneous transfer of the supporting function from
one side to the other of the electromagnets of the supporting
function from one side to the other of the electromagnets of the
two principal rows. However, this shock is minimal since the
increase of the magnet resistance at the transferor set or subrow,
as the end of the transferor rail is passed, is more or less
gradual as is the decrease in the magnetic resistance of the other
electromagnet set or subrow approaches the start of the other or
transferee armature rail. In practice, therefore, both magnets 6',
7' or 8', 9' generate an approximately constant force even where
the terminating and starting rails have coincidental ends in a
vertical plane through the track.
Preferably, however, the supporting function is shifted from one
armature rail to the other of each pair of confunctioning armature
rails (consisting of the transferee rail and the transferor rail of
the same electromagnet arrangement), by constructing the two
armature rails 10, 16 or 11, 17 with an overlap for some distance
in the direction of vehicle movement (lateral overlap) and by
arranging the rails in the overlap region such that the transferor
rail progressively recedes from the path of the electromagnet
cooperating therewith, whereas the transferee rail progressively
approaches the path of the electromagnets cooperating therewith as
shown generally in FIGS. 3, 3A 4 and 4A.
Thus in FIGS. 3 and 3A, there has been illustrated an arrangement
of the track structure in which the support flange 13 for each
armature rail 10 is shown to be of a constant level but the pole
pieces 22 progressively recede from or approach the path of the
respective set of electromagnets with a taper to the right, finally
disappearing entirely (FIG. 3A).
In the system of FIG. 4, beam 13' is provided with a slope or
inclination with respect to the path of the associated set of
electromagnets, while the pole pieces 22' are of a constant height
over the length of rail 10' (see FIG. 4A). The normal position of
the pole faces (when they do not recede from the path of the
electromagnets) is represented in broken lines in FIGS. 3 and 4.
The slope of the pole pieces in FIGS. 3 and 4 is such that the
total force applied to each principal row of electromagnets or each
electromagnet arrangement is constant as the vehicle negotiates the
overlapping-rail track section.
In FIGS. 5 and 6, there have been illustrated possible
constructions of vehicle switching arrangements according to the
present invention. In the system of FIG. 5 the track system is
provided with a pair of outer support beams 13 and 14 (channel
construction) for both the main track and the branch, whereas the
main track and branch of FIG. 6 are of the central type, i.e.,
provided with a central support beam 15. Of course, other
configurations may be employed such that the vehicle, after
transversing a track section of the central type, is transferred to
a channel track section or vice versa.
While the switching system of FIG. 5 enables the track beams 13 and
14 to extend continuously (without interruption at the junction),
the armature rails 10' and 11' of FIG. 5 and all of those of the
system of FIG. 6 must be interrupted at the junction. In FIGS. 5
and 6, the paths of the vehicle are shown as dot-dash traces.
In the junction of FIG. 6, the transfer between one track section
and the other is accomplished by providing their central supports
25, 26 and 27 in partly overlapping and partly coterminous
relationship of the armature rails. If one assumes a movement of
the vehicle upwardly along the straight portion of the junction,
the armature rail cooperating with the outer set of electromagnets
on the right-hand side of the vehicle is rendered ineffective as
armature rail 14 branches away from the straight track while an
armature rail of the central member 25 becomes effective in
cooperation with the inner set of magnets of the right
electromagnetic arrangement. Similarly, as each electromagnet
arrangement crosses the junction it is supported temporarily by a
central armature rail.
The operation of the junction can be more readily understood with
reference to the position planes A through L.
When the vehicle is in the position represented at A, it is
supported by the external armature rails 10 and 11 which cooperate
with the electromagnet arrangement 6, and 9. At this point the
inner armature rails 10b and 11a are progressively encountered and
electromagnetic subrow 7 and 8 become effective. The system of
either of FIGS. 3 and 4 can be used to ensure a constant supporting
force at both electromagnetic arrangements 6, 7 and 8, 9 in the
region between positions A and B. As shown in FIG. 7, for example,
the armature rails 10 and 10a may both have foreshortened pole
pieces 22 (by comparison with the normal height of the pole pieces)
so that a total magnetic resistance remains the same and no net
magnetic force is applied to the system. In the region between
positions B and C, all four electromagnetics are effective and it
is possible to control the electromagnetic effect of either the
sets of electromagnets on the right hand said of the vehicle or the
set of electromagnets at the left hand side of the vehicle so that
the vehicle may be deflected to the right (onto the branch track)
or may be retained generally to the left (to continue along the
straight track) as desired. Branching thus occurs between positions
C and D and may be controlled by applying coils 29 to the armature
rail sections in this region as illustrated for the coil 29 in FIG.
8 a or the coils 29' in FIG. 8b. These coils are excited to
generate magnetic fields counter to the magnetic fields produced by
the electromagnets 6 through 9 of the vehicle, i.e., to annul the
suspending field. As has been illustrated in FIGS. 8a and 8b the
coils 29 and 29' can be provided on the web of the armature rail or
upon the shanks thereof.
When the vehicle is to continue along the straight track, the left
hand rail 10 must be maintained effective, while the right hand
rail 10a of the pair is rendered progressively ineffective at least
in the region between locations B and D. The sensor 23 associated
with rail 10 in this region is thus effective to maintain the
entire load supporting force between rail 10 and its row of
electromagnets (6) while the sensors in the region B-D for rail 10a
may energize the coils 29 or 29' thereof to completely balance any
supporting contribution from the electromagnets 7. With respect to
the right hand trace during this interval, it will be apparent
that, in the region B-D the sensors 23 associated with rail 11 will
control the coils 29 or 29' thereof to completely balance any
supporting contribution by electromagnets 9 (FIG. 7) while rail 11a
is maintained fully effective in this region by cooperation with
the electromagnets 8. As a consequence, while the vehicle is fully
supported by the two principal rows of electromagnets, this support
is asymmetric since both rail 10 and rail 11a act upon the right
hand subrow or set of electromagnetics to conduct the vehicle to
the left.
When the vehicle reaches the location E, rail 11a terminates and is
functionally replaced by rail 11b of central member 27, the sensors
23 of the rails automatically energizing the coils 29 or 29' of the
rail 11a to annul the magnetic field applied by the electromagnets
8 while the full field of electromagnets 9 are applied to the rail
11b. This condition continues as the vehicle passes through the
region E-G, whereupon sensors 23, represented by circles in FIGS. 5
and 6, effect a switchover of the support function from rail
section 11b to rail section 11c. From the region J through L, the
rail section 11c overlaps a rail section 11' of the channel track
on the opposite side of the junction and a transfer is effected as
has been described in connection with FIGS. 3 and 4. At the
locations at which rails terminate without overlapping, i.e., in
the regions E and G, the sensors 23 of the appropriate row of
electromagnets (e.g., row 9) are effective to control the
suspension and guide functions.
At G, the next armature rail transfer point or crossing of the
paths of the vehicle (as illustrated in dot-dash lines for the rows
of electromagnets), the magnets of row 8 beneath the armature rail
11c become effective under the control of the sensors 23 thereof.
So that the unused rails do not effect the movement of the vehicle
through the system, rail portions 10b and 10c are energized by
their coils 29 and 29' between the regions F and H to counteract
any magnetic field which may be induced by the vehicle therein. At
location J, as noted, the vehicle is transferred from the central
switching member 26 to the beam 14' of the channel track continuing
beyond the junction and at K, the pole surface of the armature rail
11' of this beam can be considered to reach it final level after
converging toward the path of the elecctromagnets as described in
connection with FIGS. 3 and 4. From this region, the rail 11c may
converge from the path sharply. Of course, the sensors 23
associated with the electromagnet 8 will be automatically switched
over to the sensors 23 of the electromagnet row 9.
The reverse operation of the junction of FIG. 5 will also be
apparent and will follow the pattern previously described. As the
vehicle enters the junction from the right, for example, the left
hand electromagnetic arrangement will be continuously cooperating
with rail 11 while the right hand electromagnetic arrangement will
initially cooperate with rail 10', then rail 10a before finally
cooperating with rail 10. When the vehicle enters from the straight
track, it will have its right hand electromagnetic arrangement in
continuous cooperation with rail 10, but the low supporting
function of rail 11' will be transferred to rail 11c, then rail 11b
and finally rail 11a before ultimately being taken up by rail 11
beyond the junction.
The centrifugal forces arising in the junction may be compensated
by automatic adjustment of the fields produced by the vehicle
electromagnets or by controlling the degree of counter-energization
of selected rails via the coils 29 and 29'. Switchover of the
spacing sensors of the electromagnet arrangement 4 is effected at
locations B, E, G and K when the junction is entered from the right
hand curved track.
FIG. 6 shows another system arrangement, however, the cooperation
of the electromagnets of the vehicle with the armature rails is
generally similar to the cooperation described in connection with
FIG. 5. In this embodiment, the central track beams 15 of the main
and branch track are supplemented by a pair of track beams 30 and
31 forming a channel structure. In this system, unlike that of FIG.
5, regardless of the direction in which the vehicle enters the
junction, each vehicle path must undergo two armature-rail
switch-overs. If the vehicle travels through the junction in a
straight path, these switchovers occur for the left hand row of
electromagnets at C and E and for the right hand row of
electromagnets at C, E, G and J if the vehicle enters the junction
in an upward direction as viewed in FIG. 6. When the vehicle is to
branch to the right, switch-overs of the left hand of the left hand
electromagnetic arrangement occurs at locations C, E and J while
switchovers ovvur at C and E for the right hand row of
electromagnets. At each armature rail transfer, there is a
corresponding switchover of the sensors 23 which will control the
electromagnets over the associated stretch of rail. In this case,
moreover, coils 29 or 29' are preferaably provided along the
armature rail sections system region B-C-D and H-J-K. The armature
rails for travel to the right are rails 16, 16b and 16" and 17, 17"
while the rails for travel straight through the junction are rails
16, 16a, 16' and 17, 17b and 17'. The various track paths are shown
at 15, 15' and 15" to represent the central track sections in these
regions.
* * * * *