LINEARANTRIEB

Description

Technical area

[0001] The present invention falls within the technical field of electric drives for track-guided land transport vehicles or rail vehicles; it relates to a linear drive for operating a vehicle along a section of a track according to the preamble of claim 1. State of the art, technological background of the invention

[0002] A linear actuator or linear motor is an electric drive device in which, unlike conventional rotating machines, the driven objects are not set in a rotating motion, but are moved along a straight or curved path. Consequently, linear actuators are not referred to as rotating, but rather as translating.

[0003] A well-known application of such linear drives has been in roller coasters for decades. Typically, roller coaster trains are catapulted into a tangle of steel tubes by an electromagnetic linear drive every two minutes. Such a roller coaster train, weighing several tons, receives its initial energy on a roughly 50-meter-long catapult track from approximately 100 pairs of linear induction motors (LIMs). Such a LIM was and remains a logical further development of a contactless acceleration system with the goal of largely mechanically maintenance-free operation. LIMs are also used in mechanical drives for door systems—for example, in supermarkets—or in passenger conveyor belts and baggage conveyors at airports.

[0004] Other electromagnetic operating principles are also of interest in roller coasters. Linear induction motors are being replaced by linear synchronous motors (LSMs), which are comparatively more efficient than LIMs. Leading roller coaster manufacturers often rely on powerful LSM acceleration tracks, which can reach top speeds of around 180 kilometers per hour.

[0005] The linear induction motor derives its functionality from the AC motor. The only and most striking difference is that it generates translational motion instead of rotational motion. The stator coils, arranged in a circle in an AC motor, are placed along a flat, linear path. The "rotor," which rotates in an AC motor, is moved along a straight path in a linear synchronous motor. When a current is passed through a copper wire, a magnetic field is created around it. The field strength depends on the applied current. To maximize the generated magnetic field and geometrically control its direction of propagation, the copper wire is wound around an elongated iron core—the ferrite core—although an ironless design is also conceivable. The result is a coil that, when a current is applied, has the same properties as a permanent magnet.A north and a south pole are created at each end of the ferrite core. In a linear motor, many such coils are connected in series. For this purpose, motor modules with three-phase coils - the stators - are arranged along a rail over the entire acceleration or catapult section. These motor modules are grouped around a linear air gap approximately 20 millimeters wide. The motor is approximately one meter long. On the train there is a copper or aluminum rail that acts as a reaction rail, known as the rotor. This reaction rail is pulled through the gap by the LIM motor without contact. The operating principle of the drive follows the law of induction. An applied alternating voltage generates a moving magnetic field in the coils of the linear motor, with a constantly alternating polarity between north and south.The traveling magnetic field moves along the catapult track; its speed is determined by the frequency of the applied current. The traveling magnetic field applied in the stator induces an electrical voltage in the "rotor medium," which sets the free electrons in motion in the reaction rail. This electron flow, in turn, generates a magnetic field. Both magnetic fields interact with each other; unlike poles attract, like poles repel. The interaction of the two magnetic fields creates a force component in the direction of the traveling magnetic field, which sets the roller coaster train in motion. The translational driving force depends on the relative velocity Δv between the train and the traveling magnetic field. If both are moving at the same speed, no opposing magnetic field is generated, and the acceleration is zero.

[0006] During the acceleration phase, the speed of the train—and thus of the rotor—is always lower than that of the driving stator field. The magnetic field generated in the rotors thus moves across the reaction rails and even jumps from car to car across neighboring reaction rails. If the speeds of the stator field and the train were equal, no voltage would be induced in the rotor, and the force driving the train would no longer be maintained. If the speed of the train were even greater than that of the stator field, the direction of the force would reverse, and the train would be decelerated. Such relationships are known to result from the physical law of induction.

[0007] A known linear drive is disclosed in EP 3 107 195 A1; it relates to a linear motor drive system for accelerating a vehicle within an acceleration section on a travel track. The linear motor drive system comprises a stator with at least two stator elements arranged along the travel track, wherein the stator elements are combined into stator groups. The linear motor drive system further comprises a rotor which is fastened to the vehicle. Each stator group is permanently connected to its own energy converter for power supply, which energy converter can be controlled individually. At least two of the stator groups are arranged such that the rotor can interact with these two stator groups simultaneously. The present linear motor drive system is suitable for accelerating a vehicle for passenger transport in an amusement facility, such as a roller coaster.EP 2 269 289 B1 describes a transport device based on an eddy current drive. The device comprises a rail and two parallel turntables driven by an electric motor. The turntables are provided with magnets around their circumference. The drive is intended, for example, for rail-guided carriages. Furthermore, US 2003 / 205163 A1 describes a system with which carriages can be levited and accelerated. WO 2015 / 191935 A1 describes a drive and a control system for magnetically lifting a vehicle. For this purpose, a levitation drive has rotating disks equipped with magnets that induce eddy currents in a base. JP H09 261805 A discloses a magnetic levitation drive in which rotating magnetic disks are arranged opposite a conductor track and lift a vehicle and drive it linearly along the track. Description of the invention

[0008] It is an object of the present invention to further develop a linear drive in such a way that a simpler and more efficient system design of this linear drive is enabled, which has a more space-saving overall system installation compared to conventional linear drives.

[0009] The problem underlying this invention for the linear drive is solved by the features of claim 1; the features further developing this inventive concept are the subject of subclaims 2 to 11.

[0010] The essence of the present invention is that a linear drive comprises a primary part and a secondary part which is magnetically operatively connected thereto, wherein the primary part is designed as at least one first reaction rail and the secondary part comprises a number of magnets, wherein the secondary part comprises a first magnetic wheel and at least one second magnetic wheel arranged parallel thereto, and the number of magnets are arranged on the first magnetic wheel and the second magnetic wheel, and wherein the at least one first reaction rail is arranged between the first magnetic wheel and the second magnetic wheel and is magnetically operatively connected thereto.The secondary part is mechanically connected to a rotary drive, so that when the linear drive is started up, the rotation of the secondary part generates eddy currents in the reaction rail, resulting in a driving force and driving the secondary part translationally relative to the primary part. The secondary part, as well as the first magnetic wheel (3a) and the second magnetic wheel (3b), are arranged horizontally. When the linear drive is started up, in addition to the translational driving force, a further lifting force results, which leads to a lifting of the first and second wheels relative to the primary part.

[0011] In summary, it can be stated that the magnetic fields alternately aligned by the magnets on the circumference of the secondary part are set in motion by the rotation of the rotary drive relative to the primary part in such a way that eddy currents I are formed in the primary part, which is designed as a reaction rail. These eddy currents, in turn, interact with these alternately aligned magnetic fields in such a way that a desired mechanical force is consequently provided; thus, the primary part is "virtually simulated to have an infinite longitudinal extension" by means of the rotatable secondary part.Thus, the subsystem installation with regard to the secondary part essentially comprises the magnetic wheels with the rotary drive that drives them in a compact unit that can be concentrated in one area of ​​a vehicle and is also available for use over the entire route. This unit interacts with the primary part at any point along the route where it is located, both (positively) accelerating and decelerating. Of course, several of these magnetic wheel systems can also be installed per vehicle, which can increase the overall system performance and / or make the multiple drive units smaller for a given overall system performance.

[0012] It is particularly advantageous that the invention allows for a significantly shorter secondary part in relation to the length of known vehicles than conventional secondary parts, which are often arranged approximately along the entire length of the vehicle.

[0013] The amount of propulsion force can be adjusted by controlling the rotation speed of the rotary drive; the direction of rotation—forward or backward relative to the direction of travel of a vehicle—determines the type of acceleration in terms of speed increase or speed reduction.

[0014] The primary part, designed as a reaction rail, is made of an electrically conductive material to generate the necessary eddy currents I; for example, the reaction rail can be made of copper or aluminum, which has a comparatively poor conductivity and is advantageously significantly lighter and also cheaper; other electrically conductive materials can also be used.

[0015] The presently simple design of the subsystem installation with regard to the primary part, namely as a simple reaction rail, now allows the entire track of a conventional amusement ride to be equipped with such a reaction rail, whereby the vehicle speed can be permanently controlled.

[0016] Compared to the prior art, the invention now provides for the first time a linear drive whose overall system installation is significantly simpler to implement and during whose operation the energy consumption no longer has to be concentrated only on conventional individual acceleration section sections, but can be distributed over the entire travel distance.

[0017] The invention provides that the secondary part comprises the first magnetic wheel and a second magnetic wheel arranged parallel thereto, wherein the at least one first reaction rail is arranged between the first magnetic wheel and the second magnetic wheel and is magnetically operatively connected to both wheels, as described above. The secondary part, as well as the first magnetic wheel and the second magnetic wheel, are arranged horizontally, and the secondary part is mechanically connected to a rotary drive.

[0018] According to the invention, the magnets are arranged on a side of the first magnetic wheel and the second magnetic wheel facing the reaction rail. Opposing magnets on the first and second wheels have different polarity, as do adjacent magnets on a respective wheel.

[0019] In one embodiment of the invention, the primary part is arranged in a stationary manner and the secondary part is movable. Furthermore, in a further embodiment, the secondary part can be arranged in a stationary manner and the primary part is movable. Advantageously, in a further embodiment, the magnets are designed as permanent magnets or as separately excited electromagnets.

[0020] In order to increase the magnetic effect, it can further be provided that the magnets designed as externally excited electromagnets comprise a ferrite core.

[0021] An advantageous embodiment provides that the secondary part and the rotary drive are arranged on a drive platform, whereby a unit that is as compact as possible can be provided.

[0022] Advantageously, in one embodiment, the linear drive has a magnetic operative connection between the primary part and the secondary part as an asynchronous coupling, wherein a number of eddy currents I can be induced in the primary part.

[0023] In a further advantageous embodiment of the invention, it is provided that the primary part comprises at least one reaction rail and, parallel thereto, at least a second reaction rail, which are magnetically connected to the secondary part, wherein the secondary part comprises the first and second magnetic wheels and also at least one third magnetic wheel; by this parallel arrangement of two - or possibly more - reaction rails, the overall system performance can be increased in a concentrated design.

[0024] Furthermore, in a further embodiment of the linear drive according to the invention, it can be provided that the rotary drive is designed as an electric or as a hydraulic or as a pneumatic machine or that the rotary drive can be designed as a combined drive from the group of electric, hydraulic or pneumatic machines.

[0025] Further embodiments of the linear drive according to the invention and their associated advantages are the subject of the detailed description and the figures. Short description of the drawings

[0026] The invention is explained below by way of example with reference to figures. Identical objects are generally provided with the same reference numerals in the figures. It should be noted that the figures do not limit the subject matter of the invention as such, but merely show exemplary embodiments of the inventive concept—as presented in the claims.

[0027] They show purely schematically the Fig.1a, 1b and 1c a linear drive not according to the invention with a primary part designed as a reaction rail and a secondary part which comprises a first magnetic wheel, or a first and a second magnetic wheel, which in Fig. 1c are presented in more detail; Fig. 2a bis Fig. 2c Embodiments of the linear drive based on Fig. 1a with differently equipped magnetic carrying wheels; Fig. 3 another embodiment of the linear drive according to Fig. 1a , which is arranged on a drive platform of a vehicle (not shown in detail), and Fig. 4a, 4b, 4c Embodiments of the linear drive according to the invention based on Fig. 1a , the magnetic carrying wheels of which are arranged horizontally. Ways to implement the invention

[0028] Fig. 1a shows an embodiment of a part of a linear drive 1 in a perspective top view, which, although not in accordance with the invention, is helpful for understanding the linear drive according to the invention. The illustrated part of the linear drive 1 essentially comprises at least one primary part 5 designed as a reaction rail 5a with a return plate 5c, furthermore a secondary part 3, of which a first magnetic wheel 3a is shown, and a rotary drive 2, which is mechanically connected to the first magnetic wheel 3a. The first magnetic wheel 3a is equipped with magnets 4 in such a way that these magnets 4 generate a magnetic field penetrating the reaction rail 5a and induce a number of eddy currents I 8 in this reaction rail 5a, which eddy currents interact with the magnetic field, the magnetic field being closed in a known manner via the return plate 5c of the primary part 5.

[0029] In the Fig. 1b 1 shows the linear drive 1, which is also not according to the invention but is helpful for understanding the linear drive according to the invention, wherein in addition to the first magnetic wheel 3a, at least one second magnetic wheel 3b of the secondary part 3 is shown, wherein the first and second magnetic wheels 3a, 3b are arranged parallel to one another on a common axis 15 of the rotary drive 2, and wherein the first and second magnetic wheels 3a, 3b are spaced apart from one another on this axis 15 such that the at least one first reaction rail 5 can be arranged in a magnetically operative connection therebetween. According to the invention, the secondary part 3 as well as the first magnetic wheel 3a and the second magnetic wheel 3b are arranged horizontally, as in the Figuren 4a bis 4c is shown in more detail.

[0030] The first and / or the second magnetic wheel 3a, 3b is / are equipped with magnets 4, in such a way that these magnets 4 generate the magnetic field B 6 between this first and this second magnetic wheel 3a, 3b, which magnetic field B 6 also penetrates the reaction rail 5a and thereby interacts with it. Fig. 1c shows additional possible arrangements of the magnets 4 on the first and second magnetic wheels 3a, 3b. In the present case, the secondary part 3 is in Fig. 1c in a plan view of the first magnetic wheel 3a and the second magnetic wheel 3b, wherein on one of the two the magnets 4a are designed as permanent magnets 4a and on the other as electromagnets 4b, optionally with a respective ferrite core 4c. When designing the linear drive 1, it is necessary to determine which type of magnets 4 are to be used, permanent magnets 4a and / or electromagnets 4b with or without a ferrite core 4c. In this context, a look at the Fig. 2a bis 2c additionally helpful: For example, in Fig. 2a the secondary part 3 is shown in a simplified side view, whereby permanent magnets 4a facing each other are used, in Fig. 2b facing electromagnets 4b, in Fig. 2c facing permanent magnets 4a and electromagnets 4b. It is well known that for the purpose of the expected magnetic field B 6 in Fig. 1b , adjacent magnets 4 on the respective first or second magnetic wheel 3a, 3b, have a different polarity and also opposite magnets 4 on the one hand on the first magnetic wheel 3a and on the other hand on the second magnetic wheel 3b, provided that both are equipped with magnets 4 as in the Fig. 2a bis 2c shown as an example. In Fig. 1b The magnetic field B6 is shown using an example, which magnetic field B6 is generated between the first and second wheels 3a, 3b by the two associated magnets 4 with the polarities "N" and "S", respectively. In the circumferential direction of the first and second magnetic wheels 3a, 3b, the direction of the magnetic field B6 alternates with the adjacent magnet 4, although this is not explicitly shown here for the sake of simplicity. However, such magnet arrangements are sufficiently well known in the technical field of electrical machines, so that such magnet arrangements can be assumed to be immediately and clearly known even without a more detailed pictorial representation than that shown in the present figures.

[0031] When the linear drive 1 is started up, the rotary drive 2 sets the secondary part 3 in a rotating motion with the direction of rotation 7b, whereby the magnets 4 periodically rotate in and out of the area of ​​the reaction rail 5a. This creates eddy currents 8 in the reaction rail 5a, the current directions of which result from the directions of the respective magnetic field B6. Each induced eddy current 8 is aligned such that the induced eddy current magnetic field attempts to counteract the magnetic field B6, resulting in a repulsive force with the direction of force 7a, and the secondary part 3 is driven translationally relative to the primary part 5. The coordinate system 17 in Fig. 1a This illustrates once again the mutually perpendicular direction of the eddy currents I 8 to the magnetic field B 6 and the resulting force direction F 7a, which provides the translational drive. The necessary power supply for the rotary drive 2 is not shown in detail here; this power supply for the rotary drive 2 can be provided by an electrical supply, a hydraulic or pneumatic supply, or even a combination of two or three of the aforementioned power supply options. Figur 3 It is shown that the secondary part 3 of the linear drive 1 with the rotary drive 2 is arranged on a support frame 11 of a drive platform 10 of a vehicle not shown in detail here, wherein a power supply 12, 12b of the linear drive 1 on the drive platform 10 can be provided via a number of current collectors 16 on busbars 9. Further examples of power supplies 12a or 12c are additionally indicated symbolically here; a more detailed explanation of the same does not appear necessary in view of expert knowledge.

[0032] For the sake of clarity, it should be noted at this point that—without departing from the spirit of the invention—it is optionally possible to design the primary part 5 or the secondary part 3 as stationary and the other part as movable. Of course, during driving operation, it is also conceivable to initiate braking by changing the direction of rotation of the rotary drive 2 and—if electromagnets 4b are arranged on the secondary part 3—to also at least partially recuperate the braking energy.

[0033] The Fig. 4a und 4b show examples of the linear drive 1 according to the invention, in which a horizontal arrangement of the secondary part 3 or the first and second magnetic wheels 3a, 3b is present. In Fig. 4a For example, one leg of an L-profile beam 14a serves as a reaction rail and in Fig. 4b a leg of an H-profile beam 14b. Apart from the Fig. 1a discussed functionality for the translational drive in force direction F 7a, see also Fig. 1a , a further force results during operation, namely a lifting force with a lifting force direction 13, which - as shown here - means that the first and second wheels 3a, 3b are raised relative to the stationary L-profile support 14a and relative to the stationary H-profile support 14b, respectively. With appropriate dimensioning and design, it is thus conceivable to lift a vehicle, which not only reduces energy consumption during operation but also wear, particularly at high vehicle speeds. For purely informational purposes, it should be noted that with the linear drive according to the invention, vehicle speeds significantly in excess of 200 kilometers per hour can be achieved.

[0034] The Fig. 4c showed a further embodiment of the invention, in which, compared to the embodiment in Fig. 4b , a further second reaction rail 5b is shown, arranged parallel to the first reaction rail 5a, which is in operative connection with a further magnetic wheel 3c. Bezugszeichenliste

[0035] 1Linear drive 2Rotary drive 3, 3a, 3b, 3cSecondary part; First, second, third magnetic wheel 4, 4a, 4b Magnets, permanent magnets, electromagnets, with N=north pole and S=south pole 4c Ferrite core for electromagnets 5, 5a, 5b, 5c Primary part, first or second reaction rail, return plate 6 Magnetic field B, with N=north pole and S=south pole 7a Direction of force (F) of 3, translational 7b Direction of rotation of 3 8 Eddy currents I in 5 9 Power rails for supplying 2 10 Drive platform (for one vehicle) 11 Support frame 12, 12a, 12b, 12c Energy supply 13 Direction of lifting force (levitation) 14a L-profile support for 5 14b H-profile support for 5 15 Axle 16 Current collector at 9 17 Coordinate system

Claims

1. Linear drive system (1), comprising a primary part (5) and a secondary part (3) that is magnetically coupled to the primary part, wherein the primary part (5) includes at least one first electrically conductive reaction rail (5a), and the secondary part (3) includes a number of magnets (4), wherein the secondary part (3) includes a first magnetic wheel (3a) and at least one second magnetic wheel (3b) arranged parallel to the first, with the number of magnets (4) positioned on both the first magnetic wheel (3a) and the second magnetic wheel (3b), wherein the at least one first reaction rail (5a) is arranged between the first magnetic wheel (3a) and the second magnetic wheel (3b) and magnetically connected to them, wherein the secondary part (3) is mechanically connected to a rotary drive (2), so that, upon activation of the linear drive system (1), eddy currents (8) are generated in the reaction rail (5a) by the rotation of the secondary part, resulting in a driving force (7a), wherein the secondary part (3) is driven translationally relative to the primary part (5), characterized in that the secondary part (3), as well as the first magnetic wheel (3a) and the second magnetic wheel (3b), are arranged horizontally, so that, upon activation of the linear drive system (1), in addition to the translational driving force (7a), an additional lifting force (13) is generated, causing the first and second wheels (3a, 3b) to lift relative to the primary part (5).

2. Linear drive system (1) according to claim 1, characterized in that the primary part (5) includes, in addition to the at least one first reaction rail (5a), at least one second reaction rail (5b) arranged parallel to the first and the secondary part (3) includes, in addition to the at least one first magnetic wheel (3a) and the at least one second magnetic wheel (3b), a third magnetic wheel (3c) arranged parallel to the first two, wherein the second reaction rail (5b) is positioned between the second magnetic wheel (3b) and the third magnetic wheels (3c) and is magnetically coupled to the latter.

3. Linear drive system (1) according to claim 2, characterized in that a number of magnets (4) are arranged on the second magnetic wheel (3b) and / or the third magnetic wheel (3c).

4. Linear drive system (1) according to any one of claims 1 to 3, characterized in that the primary part (5) is arranged in a fixed position and the secondary part (3) is movable.

5. Linear drive system (1) according to any one of claims 1 to 3, characterized in that the secondary part (3) is arranged in a fixed position and the primary part (5) is movable.

6. Linear drive system (1) according to any one of the preceding claims, characterized in that the magnets (4) are designed as permanent magnets.

7. Linear drive system (1) according to any one of the preceding claims 1 to 6, characterized in that the magnets (4) are designed as externally excited electromagnets.

8. Linear drive system (1) according to claim 7, characterized in that the magnets (4) designed as externally excited electromagnets comprise a ferrite core (4c).

9. Linear drive system (1) according to one of the preceding claims, characterized in that the secondary part (3) and the rotary drive (2) are arranged on a drive platform (10).

10. Linear drive system (1) according to any one of the preceding claims, characterized in that the rotary drive (2) is designed as an electric or as a hydraulic or as a pneumatic machine, or in that the rotary drive (2) is designed as a combined drive from the group of electric, hydraulic or pneumatic machines.