Transport system comprising a pair of rails and a rail vehicle
Patent Information
- Application Number
- EP2023809453
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-03-29
- Filing Date
- 2023-11-13
- Publication Date
- 2025-11-05
AI Technical Summary
Existing transport systems with contactless energy transmission for rail vehicles face challenges in ensuring safe operation at high temperatures and preventing electric shock risks due to potential insulation defects, and they lack efficient energy transfer and cooling mechanisms.
A transport system with a pair of parallel rails, a primary conductor, and a rail vehicle featuring an electrically conductive chassis and wheels, a receiving unit with a ferrite core and Peltier element for efficient energy transfer and cooling, and grounding connections to prevent voltage hazards, allowing for safe operation in high-temperature environments without the need for insulating coatings.
The system enables safe, efficient, and wear-free energy transfer to the rail vehicle, preventing electric shock and overheating, while allowing operation in high-temperature environments without coolant loss or separate grounding requirements.
Smart Images
Figure 1.1
Abstract
Description
[0001] TRANSPORT SYSTEM COMPRISING A PAIR OF RAILS AND A RAIL VEHICLE
[0002] Description:
[0003] The invention relates to a transport system which comprises a pair of rails with two parallel rails, a primary conductor through which a primary current flows, and a rail vehicle.
[0004] A device for contactless energy transmission is known from DE 100 53 373 B4. The device comprises a feed that feeds a medium-frequency alternating current into an elongated primary conductor. Mobile loads are movable along the primary conductor and each have a coil that is inductively coupled to the primary conductor. This inductive coupling allows energy to be transmitted from the primary conductor to the load.
[0005] A system for contactless energy transmission is known from DE 102004 055 154 B4. The system comprises a power source connected to an elongated primary conductor. A mobile load, which is movable along the primary conductor, has a transformer. The transformer has a winding that is inductively coupled to the primary conductor. Through this inductive coupling, energy can be transmitted from the primary conductor to the transformer of the load.
[0006] A system for contactless energy transfer for charging a locomotive battery is known from CN 104 104 139 A.
[0007] A vehicle is known from CN 207 916 545 U that includes a battery. The battery can be charged via a charging interface.
[0008] US 2021 / 0020348 A1 discloses a system for contactless energy transfer that is suitable for operation at high ambient temperatures.
[0009] DE 102019216 971 A1 describes an induction charging device for a vehicle charging system. The induction charging device includes a cooling device. A system for contactless energy transfer is also described in the manual "Contactless Energy Transfer MOVITRANS - Protective Measures and Planning Information for Systems," SEW-Eurodrive GmbH & Co KG, edition 08 / 2022, document no. 27789918 / DE.
[0010] Transport systems are known from use which comprise a pair of rails with two parallel rails, a primary conductor through which a primary current flows, and a rail vehicle.
[0011] The invention is based on the object of developing a transport system of the type mentioned at the beginning.
[0012] The object is achieved according to the invention by a transport system having the features specified in claim 1. Advantageous embodiments and further developments are the subject of the subclaims.
[0013] A transport system according to the invention comprises a pair of rails with two parallel rails, a primary conductor through which a primary current flows, and a rail vehicle. The rail vehicle has a chassis, several wheels rotatably mounted relative to the chassis, an electric motor for driving the wheels, and a receiving unit for contactlessly receiving energy from the primary conductor. The chassis has an electrically conductive housing, the wheels are electrically conductive, and the rails are electrically conductive. There is an electrically conductive connection between the chassis housing and the wheels, as well as an electrically conductive connection between the wheels and the rails.
[0014] The energy transfer from the primary conductor to the receiving unit is contactless and wear-free. The rail vehicle stands on the rails or moves along the rails, with the wheels in direct contact with the rails. Through these electrically conductive connections, the housing of the rail vehicle's chassis is earthed via the wheels and the rails. This ensures that no dangerous voltage is present in the chassis housing if an internal fault occurs, for example due to defective insulation. There is therefore no risk of electric shock to a person when touching the chassis housing. An insulating coating or paint on the chassis housing is therefore unnecessary, and there is no risk of such a coating or paint melting or being damaged at high temperatures.This means that the rail vehicle can be used in an environment with a relatively high temperature, for example in a hardening furnace.
[0015] According to an advantageous embodiment of the invention, the rails are laid on a floor, and the transport system has at least one grounding point at which one of the rails is electrically grounded in the floor. The grounding point comprises, for example, a grounding rail embedded in the floor. The grounding point reduces the grounding resistance of the transport system.
[0016] According to an advantageous embodiment of the invention, the receiving unit comprises a secondary coil and a ferrite core. An electrically conductive connection exists between the chassis housing and the ferrite core. The ferrite core has a relatively high magnetic permeability. This increases the efficiency of energy transfer from the primary conductor to the receiving unit. The ferrite core is also grounded via the chassis housing, providing protection for a person touching the ferrite core.
[0017] According to an advantageous embodiment of the invention, the rail vehicle has a cooling device for cooling the ferrite core. The magnetic permeability of the ferrite core decreases with increasing temperature. The cooling device prevents the ferrite core from overheating in a relatively high-temperature environment, for example, in a furnace.
[0018] According to an advantageous embodiment of the invention, the cooling device comprises a liquid tank from which a cooling liquid can be delivered to the ferrite core. The cooling liquid is sprayed onto the ferrite core at defined intervals, for example, when the rail vehicle is in an environment with a relatively high temperature. The ferrite core is thereby cooled. The cooling liquid then drips onto the ground and subsequently evaporates or vaporizes. When the rail vehicle leaves the environment with a relatively high temperature, the liquid tank is refilled with cooling liquid.
[0019] According to an advantageous embodiment of the invention, the cooling device has a fluid circuit through which the coolant can be conveyed from the fluid tank to the ferrite core and back to the fluid tank. The coolant is pumped along a surface of the ferrite core by means of a pump. The ferrite core is thereby cooled. No coolant is lost, thus eliminating the need to refill the coolant.
[0020] According to an advantageous embodiment of the invention, the cooling device comprises a Peltier element comprising a cold side and a hot side, which is arranged on the ferrite core such that the cold side faces the ferrite core and the hot side faces away from the ferrite core. The Peltier element transports heat away from the ferrite core. The Peltier element thus cools the ferrite core.
[0021] According to an advantageous embodiment of the invention, the Peltier element is arranged on a first side of the ferrite core, and a thermal insulation medium is arranged on a second side of the ferrite core, which is opposite the first side. The thermal insulation medium is designed, for example, as a ceramic layer or an insulating foil and reduces heating of the ferrite core in a relatively high-temperature environment.
[0022] According to an advantageous embodiment of the invention, the Peltier element has a positive electrode and a negative electrode. There is an electrically conductive connection between one of the electrodes and the ferrite core, and there is an electrically conductive connection between said electrode and the chassis housing. The ferrite core is thus grounded via said electrode of the Peltier element and therefore does not require a separate grounding connection.
[0023] According to an advantageous embodiment of the invention, the cold side of the Peltier element has a metallic surface that directly contacts the ferrite core. There is an electrically conductive connection between the metallic surface and the ferrite core, and there is an electrically conductive connection between the metallic surface and the chassis housing. The ferrite core is thus grounded via the metallic surface of the Peltier element and therefore does not require a separate grounding connection.
[0024] According to an advantageous embodiment of the invention, the Peltier element has a positive electrode and a negative electrode. One of the electrodes is electrically connected to the metallic surface. According to an advantageous embodiment of the invention, the receiving unit has an electrically conductive housing. There is an electrically conductive connection between the chassis housing and the housing of the receiving unit. The housing of the receiving unit is thus also grounded via the chassis housing, providing protection for a person when touching the housing of the receiving unit.
[0025] According to an advantageous embodiment of the invention, the electric motor has an electrically conductive housing. An electrically conductive connection exists between the chassis housing and the electric motor housing. The electric motor housing is thus also grounded via the chassis housing, providing protection for a person when touching the electric motor housing.
[0026] According to an advantageous embodiment of the invention, the rail vehicle has a rectifier for converting an alternating current supplied by the receiving unit into a direct current, and the rectifier has an electrically conductive housing. An electrically conductive connection exists between the chassis housing and the rectifier housing. The rectifier housing is thus also grounded via the chassis housing, providing protection for a person touching the rectifier housing.
[0027] According to an advantageous embodiment of the invention, the rail vehicle has a control unit for controlling the electric motor, and the control unit has an electrically conductive housing. An electrically conductive connection exists between the chassis housing and the control unit housing. The control unit housing is thus also grounded via the chassis housing, providing protection for a person when touching the control unit housing.
[0028] The invention is not limited to the combination of features in the claims. Further possible combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent to those skilled in the art, particularly from the task and / or the problem posed by comparison with the prior art. The invention will now be explained in more detail with reference to figures. The invention is not limited to the exemplary embodiments shown in the figures. The figures represent the subject matter of the invention only schematically. It shows:
[0029] Figure 1: a schematic representation of a transport system.
[0030] Figure 1 shows a schematic representation of a transport system. The transport system is used to transport objects within a technical facility. The technical facility is an industrial application, for example, a production plant for the manufacture of gears and transmissions. The technical facility includes a hardening furnace for hardening the gears. A relatively high temperature prevails in the hardening furnace. The hardening furnace thus represents a relatively high-temperature environment.
[0031] The transport system comprises a pair of rails with two parallel rails 4. The rails 4 lead to the hardening furnace (not shown here). Sections of the rails 4 run straight in a longitudinal direction X. The two rails 4 are offset from one another in a transverse direction Y on a floor 5. The transverse direction Y runs perpendicular to the longitudinal direction X. A vertical direction Z runs perpendicular to the longitudinal direction X and perpendicular to the transverse direction Y. The vertical direction Z runs perpendicular to the floor 5.
[0032] The transport system comprises a primary conductor 3. The transport system further comprises an energy source 1. The energy source 1 is electrically connected to the primary conductor 3 and feeds a medium-frequency primary current with a fundamental frequency of, for example, 25 kHz or 50 kHz into the primary conductor 3. The current intensity of said primary current is, for example, 60 A or 90 A. The primary conductor 3 is thus traversed by said primary current.
[0033] The transport system also comprises a compensation unit 2. The compensation unit 2 has, among other things, a capacitor. A capacitance of the capacitor is matched to an inductance of the primary conductor 3. The compensation unit 2 thus compensates or reduces a reactive power to be supplied by the energy source 1 when feeding the primary current into the primary conductor 3. The transport system comprises a rail vehicle 8. The rail vehicle 8 has a chassis 12 and a plurality of wheels 9, which are rotatably mounted relative to the chassis 12. In the present case, the rail vehicle 8 has four wheels 9, namely two front wheels and two rear wheels. The two front wheels are arranged offset from one another in the transverse direction Y. The two rear wheels are also arranged offset from one another in the transverse direction Y. The two front wheels are arranged offset from the rear wheels in the longitudinal direction X.
[0034] The rail vehicle 8 stands with its wheels 9 on the rails 4 or moves along the rails 4 in the longitudinal direction X. The rail vehicle 8 is thus located above the rails 4 in the vertical direction Z. The wheels 9 have direct contact with the rails 4.
[0035] The transport system has a grounding point 14. In this case, the grounding point 14 comprises a grounding rail embedded in the floor 5. Said grounding rail is electrically connected to the rails 4. At the grounding point 14, the rails 4 are thus electrically grounded in the floor 5.
[0036] The rail vehicle 8 has a receiving unit 13 for contactlessly receiving energy from the primary conductor 3. The receiving unit 13 has a secondary coil and a ferrite core. The receiving unit 13 is arranged below the chassis 12 in the vertical direction Z. The primary conductor 3 is laid between the rails 4 and parallel to the rails 4 in the longitudinal direction X. The receiving unit 13 is located above the primary conductor 3 in the vertical direction Z and is magnetically coupled to the primary conductor 3.
[0037] The primary current flowing in the primary conductor 3 generates a magnetic field. The magnetic field penetrates the receiving unit 13 and induces a secondary current in the secondary coil. Thus, energy is transferred from the primary conductor 3 to the receiving unit 13 via the magnetic field, i.e., contactlessly. The secondary current in the secondary coil is an alternating current and has the same fundamental frequency as the primary current in the primary conductor 3.
[0038] The rail vehicle 8 has a rectifier 10, which is electrically connected to the receiving unit 13. The receiving unit 13 feeds the secondary current into the rectifier 10. The rectifier 10 converts the secondary current supplied by the receiving unit 13 into a direct current. The rectifier 10 supplies a direct voltage of, for example, 500 V. The rail vehicle 8 has an electrical energy storage device (not shown here). The electrical energy storage device is designed, for example, as a rechargeable battery. The rectifier 10 is electrically connected to the electrical energy storage device and feeds the direct current into the electrical energy storage device.
[0039] The rail vehicle 8 has an electric motor 6 for driving the wheels 9. The electric motor 6 is powered by the energy received by the receiving unit 13 and supplied to the rectifier 10. The electric motor 6 is embodied as a three-phase asynchronous motor in this case. Other designs of the electric motor 6 are also conceivable, for example, as a DC motor or a synchronous motor.
[0040] The rail vehicle 8 has a control unit 7 for controlling the electric motor 6. The control unit 7 is electrically connected to the rectifier 10. The control unit 7 includes, among other things, an inverter that converts the direct current supplied by the rectifier 10 into a three-phase alternating current. The control unit 7 is electrically connected to the electric motor 6 and feeds the alternating current to the electric motor 6.
[0041] The wheels 9 of the rail vehicle 8 are designed to be electrically conductive. For example, the wheels 9 are made of steel. The rails 4 are also designed to be electrically conductive and are made of steel, for example. Thus, there is an electrically conductive connection between the wheels 9 and the rails 4. The wheels 9 of the rail vehicle 8 are thus grounded via the rails 4.
[0042] The chassis 12 of the rail vehicle 8 has an electrically conductive housing, which is made of aluminum, for example. There is an electrically conductive connection between the housing of the chassis 12 and the wheels 9. The housing of the chassis 12 is thus grounded via the wheels 9 and the rails 4.
[0043] The receiving unit 13 of the rail vehicle 8 has an electrically conductive housing, which is made of aluminum, for example. A grounding strap 11 is connected to the housing of the receiving unit 13 and to the housing of the chassis 12. This creates an electrically conductive connection between the housing of the receiving unit 13 and the housing of the chassis 12. The housing of the receiving unit 13 is thus grounded via the housing of the chassis 12, the wheels 9, and the rails 4. The rectifier 10 of the rail vehicle 8 has an electrically conductive housing, which is made of aluminum, for example. A grounding strap 11 is connected to the housing of the rectifier 10 and to the housing of the chassis 12. This creates an electrically conductive connection between the housing of the rectifier 10 and the housing of the chassis 12. The housing of the rectifier 10 is thus grounded via the housing of the chassis 12, the wheels 9, and the rails 4.
[0044] The control unit 7 of the rail vehicle 8 has an electrically conductive housing, which is made of aluminum, for example. A grounding strap 11 is connected to the housing of the control unit 7 and to the housing of the chassis 12. This creates an electrically conductive connection between the housing of the control unit 7 and the housing of the chassis 12. The housing of the control unit 7 is thus grounded via the housing of the chassis 12, the wheels 9, and the rails 4.
[0045] The electric motor 6 of the rail vehicle 8 has an electrically conductive housing, which is made of aluminum, for example. A grounding strap 11 is connected to the housing of the electric motor 6 and to the housing of the chassis 12. This creates an electrically conductive connection between the housing of the electric motor 6 and the housing of the chassis 12. The housing of the electric motor 6 is thus grounded via the housing of the chassis 12, the wheels 9, and the rails 4.
[0046] Furthermore, a grounding strap 11 (not shown here) is connected to the ferrite core of the receiving unit 13 (not shown here) and to the housing of the chassis 12. This creates an electrically conductive connection between the ferrite core of the receiving unit 13 and the housing of the chassis 12. The ferrite core of the receiving unit 13 is thus grounded via the housing of the chassis 12, the wheels 9, and the rails 4.
[0047] The rail vehicle 8 has a cooling device for cooling the ferrite core. The cooling device has a Peltier element (not shown here). The Peltier element comprises a cold side and a hot side. When a direct voltage is applied to the Peltier element, the temperature on the hot side increases and the temperature on the cold side decreases. The Peltier element transports heat from the cold side to the hot side. The Peltier element is arranged on the ferrite core such that the cold side faces the ferrite core and the hot side faces away from the ferrite core. The Peltier element thus transports heat away from the ferrite core and thereby cools the ferrite core. The receiving unit 13 has a thermal insulation medium (not shown here). The thermal insulation medium is designed, for example, as a ceramic layer or as an insulating film.The Peltier element is arranged on a first side of the ferrite core, and the thermal insulation medium is arranged on a second side of the ferrite core, which is opposite the first side.
[0048] List of reference symbols
[0049] 1 power source
[0050] 2 compensation unit
[0051] 3 primary conductors
[0052] 4 rail
[0053] 5 Floor
[0054] 6 Electric motor
[0055] 7 Control unit
[0056] 8 Rail vehicle
[0057] 9 wheels
[0058] 10 rectifiers
[0059] 11 Grounding strap
[0060] 12 chassis
[0061] 13 Receiving unit
[0062] 14 Earthing point
[0063] X Longitudinal direction
[0064] Y transverse direction
[0065] Z vertical direction
Claims
Patent claims:
1. Transport system, comprising a pair of rails with two parallel rails (4), a primary conductor (3) through which a primary current flows, and a rail vehicle (8), characterized in that the rail vehicle (8) has a chassis (12), a plurality of wheels (9) which are rotatably mounted relative to the chassis (12), an electric motor (6) for driving the wheels (9), and a receiving unit (13) for contactless reception of energy from the primary conductor (3), and that the chassis (12) has an electrically conductive housing, the wheels (9) are electrically conductive, the rails (4) are electrically conductive, and that an electrically conductive connection between the housing of the chassis (12) and the wheels (9) and an electrically conductive connection between the wheels (9) and the rails (4).
2. Transport system according to claim 1, characterized in that the rails (4) are laid on a floor (5), and that the transport system has at least one earthing point (14) at which one of the rails (4) is electrically earthed in the floor (5).
3. Transport system according to one of the preceding claims, characterized in that the receiving unit (13) has a secondary coil and a ferrite core, and that an electrically conductive connection exists between the housing of the chassis (12) and the ferrite core.
4. Transport system according to claim 3, characterized in that the rail vehicle (8) has a cooling device for cooling the ferrite core.
5. Transport system according to claim 4, characterized in that the cooling device has a liquid tank from which a cooling liquid can be brought to the ferrite core.
6. Transport system according to claim 5, characterized in that the cooling device has a liquid circuit through which the cooling liquid can be brought from the liquid tank to the ferrite core and back to the liquid tank.
7. Transport system according to claim 4, characterized in that the cooling device has a Peltier element which comprises a cold side and a hot side and which is arranged on the ferrite core in such a way that the cold side faces the ferrite core and the hot side faces away from the ferrite core.
8. Transport system according to claim 7, characterized in that the Peltier element is arranged on a first side of the ferrite core, and that a thermal insulating medium is arranged on a second side of the ferrite core, which is opposite the first side.
9. Transport system according to one of claims 7 to 8, characterized in that the Peltier element has a positive electrode and a negative electrode, and that there is an electrically conductive connection between one of the electrodes and the ferrite core, and that there is an electrically conductive connection between said electrode and the housing of the chassis (12).
10. Transport system according to one of claims 7 to 9, characterized in that the cold side of the Peltier element has a metallic surface which lies directly against the ferrite core, and that there is an electrically conductive connection between the metallic surface and the ferrite core, and that there is an electrically conductive connection between the metallic surface and the housing of the chassis (12).
11. Transport system according to claim 10, characterized in that the Peltier element has a positive electrode and a negative electrode, and that one of the electrodes is electrically connected to the metallic surface.
12. Transport system according to one of the preceding claims, characterized in that the receiving unit (13) has an electrically conductive housing, and that an electrically conductive connection exists between the housing of the chassis (12) and the housing of the receiving unit (13).
13. Transport system according to one of the preceding claims, characterized in that the electric motor (6) has an electrically conductive housing, and that an electrically conductive connection exists between the housing of the chassis (12) and the housing of the electric motor (6).
14. Transport system according to one of the preceding claims, characterized in that the rail vehicle (8) has a rectifier (10) for converting a Receiving unit (13) supplied alternating current into a direct current, and that the rectifier (10) has an electrically conductive housing, and that an electrically conductive connection exists between the housing of the chassis (12) and the housing of the rectifier (10).
15. Transport system according to one of the preceding claims, characterized in that the rail vehicle (8) has a control unit (7) for controlling the electric motor (6), and that the control unit (7) has an electrically conductive housing, and that an electrically conductive connection exists between the housing of the chassis (12) and the housing of the control unit (7).