US 3851594 A
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.
Description (OCR text may contain errors)
Unite States atet n91 Schwiirzler et ai.
[ Dec. 3, 1974  Inventors:. Peter Schwa'rzler, Furstenfeldbruck; Christian Walkner, Dachau, both of Germany  Assignee: Krauss-Maffei Aktiengesellschaft,
Munich, Germany  Filed: May 21, 1973 [Zl] Appl. No.: 362,012
Related US. Application Data  Continuation-impart of Ser. No. 324,135, Jan. 16,
 Foreign Application Priority Data July 8, i972 Germany 2233631  [1.5. CI. 104/148 MS, 104/130  Int. Cl B6lb 13/08  Field of Search i. 104/148 MS, 130; 335/265, 335/285, 291
[ 56] References Cited UNITED STATES PATENTS 3,750,803 8/1973 Paxton i. l04/l48 MS FOREIGN PATENTS OR APPLICATIONS 707,032 5/l94l Germany l04/l48 MS Primary Examiner-M. Henson Wood, Jr. Assistant ExaminerGeorge H. Libman Attorney, Agent, or FirmKarl F. Ross; Herbert Dubno 57 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.
8 Claims, 11 Drawing Figures Pmmzgm 31914 31851594 sum 10F 5 PATENTEL UEB 3 I974 SHEET 2 OF .5
PATENTEL SHEET 5 BF 5 Fig. 7
ELECTROMAGNETIC SUSPENSION AND GUIDE SYSTEM FOR SUSPENDED VEHICLES ADAPTER) TO SWITCH TRACKS 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."
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 US. Pat. No. 3,804,022).
Ser. No. 268,133 filed June 30, 1972 and entitled Electromagnetic Suspension and Drive Means, (now US. 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 US. 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 US. 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 enterlaterally 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 channelshaped 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 lastmentioned 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. I, 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, 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, and C 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. I, 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 attractablc material, e.g., iron, are here shown to be fastened upon the undersides of inwardly extending transverse flanges l3 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; 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 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 representing the preferred position of a pole piece of an armature rail with which the cores 6' cooperate. Another plane P 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, and C 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 l8 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, and C respectively, for comparison with set-point signals introduced at S, and 8;. 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 or P, 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 betweentracks 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 ll, 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 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 I...
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 100 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. 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 100 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 Ila 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. and 6, effect a switchover of the support function from rail section 1112 to rail section 11c. From the region .I 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 b and 100 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 110 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 He, 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, switchovers of the left hand of the left hand electromagnetic arrangement occurs at locations C, E and .I 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 I-I-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.
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-crosssection 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 firstmentioned 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 firstmentioned 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. =0: