CONTACT ASSEMBLY FOR CHARGING STATION AND METHOD FOR ESTABLISHING CONTACT

Description

[0001] The invention relates to a contact unit for a charging station of an electrically powered vehicle and to a method for forming an electrically conductive connection between the vehicle, in particular an electric bus or the like, and the charging station, wherein the contact unit is designed to be arranged above a vehicle, wherein electrical charging contacts of the contact unit are movable relative to contact surfaces of the vehicle and can be contacted with them by means of the contact unit, wherein the contact unit has at least two charging contact carriers, each with at least two charging contacts arranged thereon, wherein the charging contact carriers are connected to each other via a parallel linkage of the contact unit with two parallel connecting rods and with two parallel support rods.wherein the support rods are each connected to the connecting rods via spaced-apart connecting joints in one of two parallel planes of movement and form a parallelogram with the connecting rods.

[0002] Such contact units and methods are known from the prior art and are regularly used in electrically powered vehicles that operate between stops. These can be electric buses, but also, in principle, other vehicles such as trains or trams that are not permanently electrically connected to an overhead wire or similar structure. In these vehicles, an electrical energy storage device is recharged at a charging station when the journey is interrupted at a stop. The vehicle is electrically connected to the charging station at the stop, whereby the energy storage device is charged at least sufficiently for the vehicle to reach the next stop with a charging station. A contact unit, mounted or positioned above the vehicle at the respective stop, is used to establish the electrical connection between the vehicle and the charging station.A charging contact on the charging station is then moved towards a contact surface on the vehicle's roof, establishing an electrical connection. For example, a contact unit can have at least four charging contacts, with two typically used for energy transfer, one as a grounding conductor, and another for data transmission. With this type of vehicle contacting, all charging stations along a route must be equipped with a corresponding contact unit, which is why the unit should be particularly cost-effective, reliable, and low-maintenance.

[0003] A key aspect of aligning charging contacts with the respective contact surfaces of the vehicle is that the charging contact is pressed onto the contact surface with a defined contact force to establish a reliable electrical connection. For example, DE 10 2013 201 491 A1 discloses a contact unit for placement above a vehicle, wherein the contact unit comprises two parallel linkages, each with two charging contacts. An actuator operates one of the parallel linkages, allowing the charging contacts to be moved relative to a contact surface on the roof of the vehicle.

[0004] A disadvantage of known charging contact units is that they must be designed or positioned for a defined contact height, meaning a specific distance between the contact unit in its retracted position (for housing the charging contacts) and the contact position for power transmission to the vehicle. This means that the relative distance between possible contact positions and the retracted position is only usable within narrow limits and must be regularly adjusted or modified through design changes, otherwise the necessary or desired contact force cannot be applied to the contact surface. Furthermore, it is important to consider that a vehicle can be loaded differently and thus tilted relative to the charging contact unit or the charging contacts. In addition, buses, in particular, can be lowered at bus stops to facilitate access for people with disabilities, for example.This potentially one-sided lowering of the bus causes a change in height or inclination of a contact surface relative to the roadway if the lowering occurs only on one side of the bus. Furthermore, the surface of the bus stop or the roadway may be inclined relative to the contact unit. A vehicle may therefore tilt or be inclined at the bus stop below the contact unit about its longitudinal and / or transverse axis. Consequently, the contact surfaces on the roof of the vehicle are then inclined in the horizontal and vertical directions relative to the charging contacts as the vehicle tilts.

[0005] While it may be possible to establish an electrical connection between the charging contacts and the contact surfaces, even if the contact unit is tiltable, the contact force exerted by the contact unit via the charging contacts onto the contact surfaces is then distributed very unevenly. Therefore, it is virtually impossible to achieve the desired contact force for a reliable electrical connection between the charging contacts and the vehicle's contact surfaces in all described cases of vehicle tilt. This also creates the risk of a charging contact lifting off a contact surface during charging, the formation of an undesirably high resistance between the charging contact and the contact surface, and the formation of an arc between the charging contact and the contact surface.

[0006] DE 10 2014 213831 A1 relates to a contact unit for power transmission for electric vehicles in connection with a stationary charging station. The charging contacts of this contact unit consist of four elongated contacts, which are arranged transversely and also longitudinally to the direction of travel of the vehicle. The contacts of the contact unit are also vertically movable.

[0007] EP 3 031 658 A1 describes a charging method for electrically powered vehicles, carried out with a contact unit attached to a charging station. The contact unit comprises two parallel contact rails extending longitudinally to the direction of travel of the vehicle, each with a charging contact, and has a height adjustment device arranged in the form of a rocker arm at the distal end of a mast of the charging station.

[0008] CN 101 580 024 A and DE 10 2013 202671 A1 concern further contact units of the type mentioned above.

[0009] It is therefore an object of the invention to propose a contact unit and a method for forming an electrically conductive connection between a vehicle and a charging station, which enables safe contacting of the vehicle.

[0010] This problem is solved by a contact unit having the features of claim 1, a charging station having the features of claim 11 and a method having the features of claim 12.

[0011] The contact unit according to the invention for a charging station of an electrically powered vehicle, in particular an electric bus or the like, is designed to be arranged above a vehicle, wherein electrical charging contacts of the contact unit are movable relative to contact surfaces of the vehicle and can be contacted by means of the contact unit, wherein the contact unit has at least two charging contact carriers, each with at least two charging contacts arranged thereon, wherein the charging contact carriers are connected to each other via a parallel linkage of the contact unit to two parallel connecting rods and to two parallel support rods, wherein the support rods are each connected to the connecting rods in one of two parallel planes of movement via connecting joints spaced apart from each other and form a parallelogram with the connecting rods.wherein the connecting rods are connected to a base support of the contact unit in a support plane running parallel and concentric to the planes of motion via two spaced-apart support joints, wherein the charging contact carriers are each connected to the support rod via a pivot joint, wherein the pivot joints are arranged orthogonally relative to the connecting joints, and wherein the charging contact carriers each hold the charging contacts coaxially relative to the axis of rotation.

[0012] The contact unit is therefore a component of a stationary charging station for an electric vehicle and serves to move the charging station's at least four charging contacts onto a contact surface of the vehicle, preferably located on the vehicle roof, and to establish electrical contact with it. This makes it possible to supply the vehicle with electrical energy during a break in driving at a charging station and to store this energy in the vehicle. The movement of the charging contacts to and from the contact surface is carried out by the contact unit or an articulated arm device of the contact unit. The charging contacts are arranged at a lower end of the contact unit, and can be moved from an upper retracted position for storing the charging contacts to a lower contact position for current transmission or contacting the contact surfaces.In the contact position, the contact unit exerts a defined and essentially equal contact force on the respective contact surfaces.

[0013] The contact unit has a base support connected to a parallel linkage via two linkage joints, which also centrally supports the linkage. The parallel linkage consists of relatively long connecting rods and short support rods, arranged vertically and connected to the connecting rods via the linkage joints. The connecting rods can thus be inclined relative to a horizontal plane, while the support rods always remain vertically aligned within the two parallel planes of movement. Because the linkage joints are coaxial with the support rod joints, a uniform force distribution is always achieved, from the contact force applied centrally to the base support to the two support rods, regardless of the inclination of the connecting rods.

[0014] The charging contact carriers are each arranged on the support rods via the swivel joint. Since the charging contacts on each charging contact carrier are also arranged coaxially relative to the swivel joint, the contact force can be distributed proportionally between the two charging contacts on each charging contact carrier via the support rods or the swivel joint. Because the swivel joints are arranged orthogonally relative to the connecting joints, it is possible to adjust the height of the charging contacts relative to the vehicle in response to lateral and longitudinal inclination, while simultaneously achieving reliable contact of the respective contact surfaces of the vehicle with an equal proportional contact force using simple means.

[0015] Accordingly, a contact force evenly distributed across the charging contacts can be exerted on them via the base carrier. If four charging contacts are present, four times the contact force can be introduced into the parallel linkage via the base carrier, or the contact force introduced into the parallel linkage via the base carrier can be distributed equally among the charging contacts.

[0016] The charging contacts can be designed as contact strips, each of which can be arranged parallel to the charging contact carriers relative to each other, with the charging contact carriers themselves also being arranged parallel to each other. The parallel arrangement, in particular, ensures that the contact force is always distributed evenly across the charging contacts. The contact strips can be easily connected to similarly strip- or rail-shaped contact surfaces on the roof of a vehicle. Preferably, the contact strips can run transversely, and especially orthogonally, relative to the contact rails. Even if a vehicle stops at a charging station in such a way that the contact strips come into contact with rail-shaped contact surfaces on the vehicle off-center, relative to their length, the contact force can still be distributed evenly.

[0017] It is therefore advantageous if the contact strips can be arranged transversely to the vehicle's direction of travel. Contact surfaces or rails on the vehicle's roof can then be arranged in the direction of travel. Alternatively, the contact strips can be arranged in the direction of travel, and the contact surfaces or rails on the vehicle's roof can be arranged transversely to the vehicle's direction of travel.

[0018] The contact unit can further comprise an articulated arm and a drive unit for actuating the articulated arm. The articulated arm can be a pantograph or a rocker arm, which can be actuated by an adjustment drive of the drive unit. The adjustment drive can be pneumatic, hydraulic, or electric, and can, for example, interact with springs of a spring assembly of the drive unit. This makes it possible to position the articulated arm relative to the contact surfaces via the drive unit so that the desired contact force is applied to the contact surfaces. In particular, the base support can be arranged or attached to a lower end of the articulated arm.In principle, the contact unit can therefore have any device that enables the base carrier to be held and moved relative to it, and allows a contact force to be exerted on the contact surfaces.

[0019] The base carrier can be connected to an articulated arm of the contact unit via at least one retaining joint. This retaining joint can allow the base carrier to pivot relative to the charging station. Alternatively, a rigid connection between the articulated arm and the contact unit can be provided.

[0020] Accordingly, the base support can be arranged vertically and rigidly connected to the articulated arm device. This ensures that the parallel linkage cannot pivot undesirably relative to the articulated arm device, for example due to wind.

[0021] The contact unit can have an alignment device by means of which, in a retracted position of the contact unit for storing the charging contacts, the charging contacts can be aligned from a contact position to a horizontal storage position. For example, if the charging contacts are made contact with the contact surfaces on a vehicle roof that is inclined relative to the charging station, it is advantageous to bring the charging contacts into a substantially horizontal position or to position them in a common horizontal plane before making contact with a potentially different vehicle.

[0022] The alignment device can be designed as a stop for the charging contact carriers. This makes it possible to move the charging contact carriers against the stop(s) in the retracted position, thereby realigning the charging contact carriers and the parallel linkage to their initial position. Such a stop(s) for the charging contact carriers are particularly easy to implement in a charging station.

[0023] Alternatively or additionally, the contact unit can have spring devices by means of which the charging contact carriers on the parallel linkage and / or the parallel linkage on the base carrier can be aligned. The spring devices can include leaf springs and / or coil springs, as well as elastic elements, by means of which the charging contact carriers on the parallel linkage, or the parallel linkage itself on the base carrier, can be subjected to a spring force when deviating from a horizontal position. This allows for the corresponding alignment of the charging contacts in a common horizontal plane even before reaching an engagement position and immediately after leaving a contact position. However, the spring force must not be so large that it significantly affects the respective contact force of the charging contact.

[0024] It is also advantageous if the parallel linkage and / or the charging contact carriers on the parallel linkage are designed to be tiltable by up to + / - 5° relative to a horizontal plane. This makes it possible to limit the tilt.

[0025] In a further embodiment of the invention, the contact unit according to the invention forms a component of a stationary charging station for electrically powered vehicles, in particular electric buses or the like.

[0026] In the inventive method for forming an electrically conductive connection between a vehicle, in particular an electric bus or the like, and a charging station, electrical charging contacts of the contact unit are moved relative to contact surfaces of the vehicle and contacted by means of an inventive contact unit of the charging station above a vehicle, wherein the contact unit has at least two charging contact carriers arranged parallel to each other, each with at least two charging contacts arranged parallel to each other, wherein the charging contacts are moved from a retraction position of the contact unit for storing the charging contacts to a contact position of the contact unit for forming electrical contact pairings between the charging contacts and the contact surfaces, wherein in the contact position an equal contact force of the charging contacts is exerted on the contact surfaces via the contact unit.Regarding the advantageous effects of the method according to the invention, reference is made to the description of advantages of the device according to the invention.

[0027] In this method, an equal contact force can be exerted on the contact surfaces by the charging contacts if the contact surfaces are arranged at an angle relative to a horizontal plane.

[0028] Further advantageous embodiments of the method are set out in the dependent claims relating to claim 1.

[0029] Preferred embodiments of the invention are explained in more detail below with reference to the accompanying drawings. They show:

[0030] Fig. 1 a contact unit in a perspective view; Fig. 2 a schematic representation of another contact unit with contact rails of a vehicle in a top view; Fig. 3 the contact unit Fig. 2 with the contact rails in a front view; Fig. 4 the contact unit Fig. 2 with the contact rails in a side view.

[0031] The Fig. 1 Figure 1 shows a contact unit 10 for a charging station of an electrically powered vehicle, wherein the contact unit 10 has a total of four charging contacts 11, which are designed as contact strips 12. Furthermore, the contact unit 10 has two charging contact carriers 13, to the distal ends 14 of which the contact strips 12 are attached. Thus, it is possible to electrically contact contact rails (not shown here) on the roof of a vehicle using an underside 15 of the contact strips 12.

[0032] The essentially arc-shaped or U-shaped charging contact carriers 13 are connected to a parallel linkage 16 of the contact unit 10, which consists of connecting rods 17 and vertically arranged support rods 18. The connecting rods 17 are movably connected to the support rods 18 via connecting joints 19, with each charging contact carrier 13 being movably connected to the support rod 18 via a pivot joint 20.

[0033] A base support 21 of the contact unit 10 is movably connected to the connecting rods 17 via support joints 22. The support joints 22 are arranged in a vertical support plane 23, with the connecting joints being arranged in vertical planes of movement 24. The planes of movement 24 are always parallel or coaxial to the support plane 23, regardless of the position or inclination of a parallelogram 25 formed by the parallel linkage 16.

[0034] The base support 21 has a support rod section 26 with two projecting arms 27. Each arm 27 has a bore 28 for connecting a hinged arm device of the contact unit 10 (not shown). In particular, the pivot joints 20 are arranged orthogonally relative to the connecting joints 19, such that a longitudinal axis 29 of the pivot joints 20 runs transversely or at a right angle to the transverse axes 30 of the connecting joints 19.

[0035] A summary of Fig. 2 bis 4Figure 1 shows a further contact unit 31 in a schematic representation together with contact rails 32, which are arranged on the roof 33 of a vehicle (not shown in detail here) in a direction of travel indicated by an arrow 35. The contact rails 32 are each positioned on U-shaped supports 34 parallel to the roof 33. The roof 33 is inclined relative to the direction of travel indicated by the arrow 35 at an angle α in a transverse direction of the vehicle and at an angle β in a longitudinal direction of the vehicle relative to a horizontal plane 36. The inclination here is no more than ± 5°.

[0036] The contact unit 31 comprises four charging contacts 37, which are designed as contact strips 38 and attached to charging contact carriers 39. The charging contact carriers 39 are in turn pivotally mounted on support rods 41 of a parallel linkage 42 via rotary joints 40. The support rods 41 are movably connected to connecting rods 44 via connecting joints 43. The connecting rods 44 are, in turn, movably connected to a substantially rigid base support 46 via support joints 45, such that the parallel linkage 42 can be tilted or inclined relative to a vertical support plane 47. The support rods 41 then move in planes of motion 48, which are always parallel and equidistant from the support plane 47. This makes it possible to form a height difference H of the contact strips 38 in the transverse direction of the vehicle with an equally distributed contact force between the contact rails 32 and the respective contact strips 38.It is also possible to pivot the charging contact carriers 39 around the swivel joint 40, which runs in the transverse direction of the vehicle, transversely to the vehicle, so that this also results in an even distribution of force with a simultaneously secure electrical contact between contact strips 38 and contact rails 32.

Claims

1. A contact unit (10, 31) for a charging station of an electrically driven vehicle, in particular an electric bus or the like, the contact unit being configured to be disposed above a vehicle, wherein electrical charging contacts (11, 37) of the contact unit are movable with respect to contact surfaces (32) of the vehicle and contact can be established between the charging contacts and the contact surfaces by means of the contact unit, the contact unit having at least two charging contact supports (13, 39) each of which has at least two charging contacts disposed thereon, the charging contact supports being connected to each other via a parallel linkage (16, 42) of the contact unit having two connecting rods (17, 44) disposed in parallel and having two support rods (18, 41) disposed in parallel, each support rod being connected to the connecting rods in one of two parallel movement planes (24, 48) via connecting hinges (19, 43) which are spaced apart from each other, and said support rods forming a parallelogram (25) with the connecting rods, characterized in that the connecting rods are connected to a base support (21, 46) of the contact unit via two support hinges (22, 45), which are spaced apart from each other, in a support plane (23, 47) extending in parallel and centrically to the movement planes, each charging contact support being connected to the support rod via a rotary hinge (20, 40), the rotary hinges being orthogonally disposed with respect to the connecting hinges, each charging contact support mounting the charging contacts coaxially with respect to the axis of rotation.

2. The contact unit according to claim 1, characterized in that the charging contacts (11, 37) are formed as contact strips (12, 38), which are each disposed in parallel with respect to each other on the charging contact supports (13, 39), the charging contact supports being disposed in parallel with respect to each other.

3. The contact unit according to claim 1 or 2, characterized in that the contact strips (12, 38) are disposable transversely to the driving direction (35) of the vehicle.

4. The contact unit according to any one of the preceding claims, characterized in that the contact unit (10, 31) has an articulated arm device and a drive device for driving the articulated arm device.

5. The contact unit according to any one of the preceding claims, characterized in that the base support (21, 46) is connected to an articulated arm device of the contact unit via at least one retaining hinge.

6. The contact unit according to claim 4 or 5, characterized in that the base support (21, 46) is rigidly connected to the articulated arm device.

7. The contact unit according to any one of the preceding claims, characterized in that the contact unit (10, 31) has an adjustment means by means of which, in a retracted position of the contact unit for storing the charging contacts, the charging contacts (11, 37) are adjustable from a contact position to a horizontal storage position.

8. The contact unit according to claim 7, characterized in that the adjustment means is formed as a stop for the charging contact supports (13, 39).

9. The contact unit according to any one of the preceding claims, characterized in that the contact unit (10, 31) has spring means by means of which the charging contact supports (13, 39) are each adjustable on the parallel linkage (16, 42) and / or the parallel linkage is adjustable on the base support (21, 46).

10. The contact unit according to any one of the preceding claims, characterized in that the parallel linkage (16, 42) and / or the charging contact supports (13, 39) on the parallel linkage are configured to be inclined by up to ± 5° with respect to a horizontal plane (36).

11. A stationary charging station for electrically driven vehicles, in particular electric busses or the like, having a contact unit (10, 31) according to any one of the preceding claims.

12. A method for forming an electrically conductive connection between a vehicle, in particular an electric bus or the like, and a charging station, wherein electrical charging contacts (11, 37) of a contact unit (10, 31) are moved with respect to contact surfaces (32) of the vehicle and contact is established between the charging contacts and the contact surfaces by means of the contact unit (10, 31) of the charging station according to any one of claims 1 to 10 above the vehicle, the contact unit having at least two charging contact supports (13, 39) disposed parallel to each other and each having at least two charging contacts disposed thereon in parallel to each other, the charging contacts being moved from a retracted position for storing the charging contacts into a contact position for forming respective electrical contact pairs between the charging contacts and the contact surfaces, characterized in that in each case, an equal contact force of the charging contacts is exerted on the contact surfaces via the contact unit in the contact position.

13. The method according to claim 12, characterized in that the equal contact force of the charging contacts (11, 37) is exerted on the contact surfaces (32) when the contact surfaces are disposed in an inclined manner with respect to a horizontal plane (36).