Current collector for an electrically or hybrid-electrically powered vehicle and a vehicle equipped with one

Abstract

The invention relates to a current collector (1) for a vehicle for supplying traction energy during travel from a contact wire (2) of an overhead line system installed along the route. It comprises at least one contact strip (3) extending parallel to a transverse direction (Y) of the vehicle and an erectable support frame (6) with a base joint for supporting the support frame (6) on the vehicle and with a joint arrangement (7) having at least one axis of rotation (D) extending parallel to the transverse direction (Y) of the vehicle for rotatably mounting the at least one contact strip (3) on the support frame (6). A lifting device serves to erect the support frame (6) and to generate a contact force (K) with which the at least one contact strip (3) can be pressed against the contact wire (2) to form an electrical sliding contact.According to the invention, the at least one axis of rotation (D) is arranged relative to the at least one contact strip (3) such that a tilting moment (MK) imposed on the at least one contact strip (3) by a frictional force (R) in the contact contact with the contact wire (2) can be compensated by an opposing counter-moment (MG) imposed on the at least one contact strip (3) by the contact force (K). This reduces the wear of the pantograph (1).

Description

[0001] The invention relates to a pantograph for an electrically or hybrid-electrically powered vehicle according to the preamble of claim 1 and to a vehicle equipped with such a pantograph according to claim 5.

[0002] Such pantographs are designed to supply traction energy to an electrically or hybrid-electrically powered vehicle, particularly heavy commercial vehicles such as trucks or buses, while it is traveling along a route from a contact wire of an overhead line system installed along the route. Such a pantograph comprises at least one elongated contact strip extending parallel to a transverse direction of the vehicle, which has an upward-facing contact surface with respect to a vertical direction of the vehicle. Furthermore, such a pantograph comprises an erectable support frame with a base hinge for supporting the support frame on the vehicle and with a pivot arrangement having at least one axis of rotation running parallel to the transverse direction of the vehicle for rotatably mounting the at least one contact strip on the support frame.Furthermore, such a pantograph includes a lifting device designed to erect the support frame, whereby the at least one contact strip moves from a lower rest position to an upper contact position. The lifting device is further designed to generate a contact force with which the at least one contact strip is pressed against the contact wire in its contact position, in order to establish an electrical sliding contact between the at least one contact strip and the contact wire during travel, for the transmission of electrical energy from the overhead line system to a vehicle-side traction drive and / or a vehicle-side energy storage device.

[0003] Patent EP 3 571 086 B1 discloses such a current collector for a two-pole overhead contact line system. The pantograph-like support frame comprises a lower arm pivotally mounted on a base joint and two upper arms pivotally mounted relative to each other on the lower arm. Each upper arm carries a contact rocker with two contact strips arranged one behind the other. The support frame can be erected by applying a suitable torque to the lower arm, whereby the upper arms are forcibly erected by a connecting rod and two pull rods until the contact rockers make contact with the contact wires, thus establishing electrical contact between the current collector and the two contact wires of the overhead contact line system. Each contact rocker is rotatably connected to its respective upper arm via a rocker joint with an axis of rotation parallel to the transverse direction of the vehicle.The axis of rotation of each contact rocker lies centrally between the contact strips with respect to a longitudinal direction of the vehicle and below the two contact strips with respect to a vertical direction of the vehicle.

[0004] German patent application DE 10 2020 211 775 A1 discloses a pantograph for an electrically or hybrid-electrically powered road vehicle, designed and intended for supplying traction energy from a two-pole overhead contact line system, each contact pole having a contact wire. The pantograph comprises an erectable support frame, which is articulatedly supported on a frame base on the vehicle side and carries a rocker assembly on the contact wire side. The rocker assembly has a rocker frame for each contact pole. Each rocker frame is articulated to the support frame, allowing it to rotate about a transverse axis of the vehicle. The support frame has an erectable support arm for each contact pole. Each support arm has a lower arm supported on the frame base and an upper arm articulated to the lower arm, which carries the respective rocker frame.Each connecting rod is articulated to the upper arm and the linkage base in such a way that, when a support arm is raised, its upper arm is extended relative to the lower arm. Each guide rod is articulated to the lower arm and the rocker frame in such a way that, when the support arm is raised, the rocker frame is guided so that a contact strip mounted on the rocker frame remains facing the contact wire. Exactly one contact strip, arranged parallel to the vehicle's transverse axis, is mounted on each rocker frame for electrical contacting the contact wire associated with the contact pole. The pivot axes connecting each rocker frame to its upper arm are located centrally to the contact strip with respect to the vehicle's longitudinal direction and below it with respect to the vehicle's vertical direction.

[0005] Due to the forces acting on the contact strip during operation, and especially when the contact wire is inclined towards the road surface, uneven wear of the contact strip in the direction of the contact wire can occur in known pantographs. Typically, the leading edge of the contact strip's contact surface is more worn than its trailing edge. Instead of the intended linear contact, the contact wire can make point contact with the contact surface, which can lead to an increased current density during operation and the risk of wear-promoting plasma flashes.

[0006] The invention is therefore based on the objective of providing a current collector of the type mentioned at the outset with improved wear behavior of its contact strip(s).

[0007] The invention solves the problem by means of a generic current collector with the features specified in the characterizing part of claim 1.

[0008] The invention therefore relates to a pantograph designed to supply traction energy to an electrically or hybrid-electrically powered vehicle while it is traveling along a track from a contact wire of an overhead line system installed along the track. The vehicle is in particular a heavy commercial vehicle, such as a truck or a bus, but can also be a rail vehicle.

[0009] Such a current collector comprises at least one elongated contact strip extending parallel to a transverse direction of the vehicle, which has an upward-facing contact surface with respect to the vehicle's vertical direction. Depending on the design, one, two, or more contact strips can be provided for each contact wire of a single- or multi-pole overhead line system. Each contact strip can have a contact piece made of graphite or copper with an approximately strip-shaped contact surface, which is mounted in a contact piece holder.

[0010] Furthermore, such a pantograph comprises an erectable support frame with a base joint for supporting the support frame on the vehicle and with a joint arrangement having at least one axis of rotation running parallel to the transverse direction of the vehicle for rotatably mounting the at least one contact strip on the support frame. The support frame can, for example, have support arms that can be erected in the manner of a pantograph and are supported via the base joint on a load-bearing structure of the vehicle.

[0011] Furthermore, such a pantograph includes a lifting device designed to raise the support frame, whereby the at least one contact strip moves from a lower rest position to an upper contact position. In the lower rest position, the pantograph can be stored in a roof area of ​​the vehicle, so that the permissible vehicle dimensions for non-electrified lines can be maintained. The lifting device is also designed to generate a contact force with which the at least one contact strip is pressed against the contact wire in its upper contact position, in order to establish an electrical sliding contact between the at least one contact strip and the contact wire during travel, for the transfer of electrical energy from the overhead line system to a vehicle-mounted traction drive and / or a vehicle-mounted energy storage device.

[0012] According to the invention, the at least one axis of rotation is arranged relative to the at least one contact strip such that a tilting moment imposed on the at least one contact strip by a frictional force in the contact contact with the contact wire can be compensated by an opposing counter-moment imposed on the at least one contact strip by the contact force. According to the invention, it was discovered that the contact force between the contact surface of the at least one contact strip and the contact wire generates a frictional force acting against the direction of travel of the vehicle, which, due to the at least one axis of rotation of the joint arrangement located below the contact surface, imposes a tilting moment on the at least one contact strip.According to the invention, the at least one axis of rotation is no longer symmetrical to the at least one contact strip with respect to the longitudinal direction of the vehicle, but is arranged asymmetrically such that the contact force exerts a counter-torque on the at least one contact strip that opposes the tilting moment. The position of the at least one axis of rotation is dimensioned relative to the at least one contact strip such that the sum of the tilting moment and the counter-torque is small or disappears. The low overall torque keeps the contact surface of the at least one contact strip parallel to the contact wire, which evens out the wear of its contact element.

[0013] In an advantageous embodiment, the current collector according to the invention comprises exactly one contact strip, wherein the articulated joint has exactly one axis of rotation which, relative to the contact strip, is located below its contact surface with respect to the vehicle's vertical direction and behind a line of action of a total force resulting from the contact force between the contact wire and the contact surface with respect to a longitudinal direction of the vehicle. The contact force between the contact strip and the contact wire is mediated via a linear bearing surface of the contact wire on the contact surface. Each component of the contact force acting on a linear element of the bearing surface imparts a torque component to the contact strip, which, integrated over the bearing line, yields the tilting moment. Alternatively, a resultant contact force and its line of action can be determined, which impart the same tilting moment.The axis of rotation of the joint arrangement is now positioned so far behind this line of action that the tilting moment caused by friction and the counter-moment caused by contact force balance each other out.

[0014] In a further advantageous embodiment, the current collector according to the invention comprises two contact strips arranged one behind the other in the direction of travel, wherein the joint arrangement has exactly one axis of rotation which is located between the two contact strips with respect to the longitudinal direction of the vehicle, wherein the axis of rotation is located below the contact surfaces of the contact strips with respect to the vehicle's vertical direction and closer to the contact strip rearward in the direction of travel than to the front contact strip with respect to the longitudinal direction of the vehicle. The two contact strips can be arranged on a common contact rocker in a mutually fixed position, which is connected to the support frame via the joint arrangement. The contact surfaces of the two contact strips lie in a common contact plane.The tilting moment is generated by the frictional forces between the two contact strips and the contact wire, while the counter-torque consists of two opposing torques. A first torque is generated by the contact force acting on the front contact strip, while a second, opposing torque is generated by the contact force acting on the rear contact strip. Because the rear contact strip is closer to the axis of rotation than the front contact strip, the first torque outweighs the second, resulting in a counter-torque that balances the tilting moment.

[0015] In a further advantageous embodiment, the current collector according to the invention comprises two contact strips arranged one behind the other in the direction of travel. The articulated arrangement includes a base element mounted on the support frame, with a first axis of rotation and a second axis of rotation arranged at a fixed distance therefrom; a front leg element rotatably connected to the base element about the first axis of rotation; a rear leg element rotatably connected to the base element about the second axis of rotation; and a support element carrying the two contact strips, with a third axis of rotation and a fourth axis of rotation arranged at a fixed distance therefrom. The front leg element and the rear leg element are each rotatably connected to the support element about the third axis of rotation and the fourth axis of rotation, respectively. The distance between the third and fourth axes of rotation is smaller than the distance between the first and second axes of rotation.In this embodiment, the base element, the support element, and the two leg elements form a so-called four-bar linkage. The frictional force acting on the contact surfaces of the contact strips causes a tilting moment on the contact strips, which rotates the front leg element around the first axis of rotation and the rear leg element around the second axis of rotation in the opposite direction of travel. This causes the support element to tilt, so that the front contact strip lowers and the rear contact strip rises, thus relieving the load on the front contact strip relative to the rear contact strip. The contact forces acting differently on the front and rear contact strips now create a counter-torque that attempts to rotate the support element with the contact strips into a position parallel to the contact wire.By arranging the sliding strips relative to the axes of rotation and by appropriately dimensioning the length of the four-bar linkage element, a counter-moment compensating for the tilting moment can be generated.

[0016] The problem is further solved by an electrically or hybrid-electrically powered vehicle, in particular a heavy commercial vehicle, with a pantograph according to one of claims 1 to 4. The vehicle can be a heavy commercial vehicle, such as a semi-trailer truck or a bus, or a rail vehicle, such as a multiple unit train or a locomotive.

[0017] Further features and advantages of the invention will become apparent from the following description of exemplary embodiments with reference to the drawings, in which Fig. 1 a first embodiment of the current collector according to the invention with a contact strip, Fig. 2 a second embodiment of the current collector according to the invention with two contact strips, Fig. 3 a third embodiment of the current collector according to the invention with two contact strips in a first state of movement, Fig. 4 the third embodiment in a second state of motion, Fig. 5 the first embodiment in a side view and Fig. 6 the first embodiment is schematically explained in a front view.

[0018] The current collectors 1 according to Fig. 1 to Fig. 6. These serve to supply traction energy to an electrically or hybrid-electrically powered vehicle while it is traveling along a track from a contact wire 2 of an overhead line system installed along the track. The vehicle, not shown, can be, in particular, a heavy commercial vehicle, such as a truck or a bus, but also a rail vehicle.

[0019] Such a current collector 1 comprises at least one elongated contact strip 3 extending parallel to a transverse direction Y of the vehicle, which has an upwardly facing contact surface 4 with respect to a vertical direction Z of the vehicle. Depending on the design, one, two, or more contact strips 3 can be provided for each contact wire 2 of a single- or multi-pole overhead line system. Each contact strip 3 can have a contact piece made of graphite or copper with an approximately strip-shaped contact surface 4, which is mounted in a contact piece holder 5.

[0020] Furthermore, such a current collector 1 comprises an erectable support frame 6 with a base joint for supporting the support frame 6 on the vehicle and with a joint arrangement 7 having at least one axis of rotation running parallel to the transverse direction Y of the vehicle for rotatably mounting the at least one contact strip on the support frame. The support frame can, for example, have support arms that can be erected in the manner of a pantograph and are supported via the base joint on a load-bearing structure of the vehicle.

[0021] Furthermore, such a pantograph includes a lifting device designed to raise the support frame, whereby the at least one contact strip moves from a lower rest position to an upper contact position. In the lower rest position, the pantograph can be stored in a roof area of ​​the vehicle, so that the permissible vehicle dimensions for non-electrified lines can be maintained. The lifting device is also designed to generate a contact force with which the at least one contact strip is pressed against the contact wire in its upper contact position, in order to establish an electrical sliding contact between the at least one contact strip and the contact wire during travel, for the transfer of electrical energy from the overhead line system to a vehicle-mounted traction drive and / or a vehicle-mounted energy storage device.

[0022] According to the invention, the at least one axis of rotation is arranged relative to the at least one contact strip such that a tilting moment imposed on the at least one contact strip by a frictional force in the contact contact with the contact wire can be compensated by an opposing counter-moment imposed on the at least one contact strip by the contact force. According to the invention, it was discovered that the contact force between the contact surface of the at least one contact strip and the contact wire generates a frictional force acting against the direction of travel of the vehicle, which, due to the at least one axis of rotation of the joint arrangement located below the contact surface, imposes a tilting moment on the at least one contact strip.According to the invention, the at least one axis of rotation is no longer symmetrical to the at least one contact strip with respect to the longitudinal direction of the vehicle, but is arranged asymmetrically such that the contact force exerts a counter-torque on the at least one contact strip that opposes the tilting moment. The position of the at least one axis of rotation is dimensioned relative to the at least one contact strip such that the sum of the tilting moment and the counter-torque is small or disappears. The low overall torque keeps the contact surface of the at least one contact strip parallel to the contact wire, which evens out the wear of its contact element.

[0023] According to Fig. 1, Fig. 5 and Fig. 6. The current collector according to the invention comprises exactly one contact strip, wherein the articulated arrangement has exactly one axis of rotation which, relative to the contact strip, is located below its contact surface with respect to the vehicle's vertical direction and behind a line of action of a total force resulting from the contact force between the contact wire and the contact surface with respect to a longitudinal direction of the vehicle. The contact force between the contact strip and the contact wire is mediated via a linear bearing surface of the contact wire on the contact surface. Each component of the contact force acting on a linear element of the bearing surface imparts a torque component to the contact strip, which, integrated over the bearing line, yields the tilting moment. Alternatively, a resultant contact force and its line of action can be determined, which imparts the same tilting moment.The axis of rotation of the joint arrangement is now positioned so far behind this line of action that the tilting moment caused by friction and the counter-moment caused by contact force balance each other out.

[0024] According to Fig. 2. The current collector according to the invention comprises two contact strips arranged one behind the other in the direction of travel, wherein the articulated assembly has exactly one axis of rotation which is located between the two contact strips with respect to the longitudinal direction of the vehicle, wherein the axis of rotation is located below the contact surfaces of the contact strips with respect to the vehicle's vertical direction and closer to the contact strip located further back in the direction of travel than to the contact strip located further forward with respect to the longitudinal direction of the vehicle. The two contact strips can be arranged on a common contact rocker in a mutually fixed position, which is connected to the support frame via the articulated assembly. The contact surfaces of the two contact strips lie in a common contact plane. The tilting moment is generated here by the frictional forces between the two contact strips and the contact wire, while the counter-torque is composed of two opposing torques.A first torque is generated by the contact force acting on the front contact strip, while a second, opposing torque is generated by the contact force acting on the rear contact strip. Because the rear contact strip is closer to the axis of rotation than the front contact strip, the first torque outweighs the second, resulting in a counter-torque that balances the tilting moment.

[0025] According to Fig. 3 and Fig.4. The current collector according to the invention comprises two contact strips arranged one behind the other in the direction of travel. The articulated assembly has a base element mounted on the support frame with a first axis of rotation and a second axis of rotation arranged at a fixed distance therefrom, a front leg element rotatably connected to the base element about the first axis of rotation, a rear leg element rotatably connected to the base element about the second axis of rotation, and a support element carrying the two contact strips with a third axis of rotation and a fourth axis of rotation arranged at a fixed distance therefrom. The front leg element and the rear leg element are each rotatably connected to the support element about the third axis of rotation. The distance between the third and fourth axes of rotation is smaller than the distance between the first and second axes of rotation.In this configuration, the base element, the support element, and the two leg elements form a so-called four-bar linkage. The frictional force acting on the contact surfaces of the contact strips creates a tilting moment on the contact strips, causing the front leg element to rotate around the first axis and the rear leg element around the second axis, opposite to the direction of travel. This tilts the support element, causing the front contact strip to lower and the rear contact strip to rise, thus relieving the load on the front contact strip relative to the rear one. The differing contact forces acting on the front and rear contact strips then create a counter-torque that attempts to rotate the support element with the contact strips into a position parallel to the contact wire.By arranging the sliding strips relative to the axes of rotation and by appropriately dimensioning the length of the four-bar linkage element, a counter-moment compensating for the tilting moment can be generated. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 3 571 086 B1

[0003] DE 10 2020 211 775 A1

[0004]

Claims

[1] Pantograph (1) for an electrically or hybrid-electrically driven vehicle, in particular for a heavy commercial vehicle, for feeding traction energy during travel along a route from a contact wire (2) of an electrical overhead line system installed along the route, comprising - at least one elongated contact strip (3) extending parallel to a vehicle transverse direction (Y) and having an upwardly facing contact surface (4) with respect to a vehicle vertical direction (Z), - an erectable support frame (6) with a base joint for supporting the support frame (6) on the vehicle and with a joint arrangement (7) with at least one axis of rotation (D) running parallel to the vehicle transverse direction (Y) for the rotatable mounting of the at least one contact strip (3) on the support frame (6), and - a lifting device for erecting the support frame (6), wherein the at least one contact strip (3) moves from a lower rest position to an upper contact position, and for generating a contact force (K) with which the at least one contact strip (3) can be pressed in its contact position against the contact wire (2) to form an electrical sliding contact, characterized by , - that the at least one axis of rotation (D) is arranged relative to the at least one contact strip (3) in such a way that, in the sliding contact with the contact wire (2), a tilting moment (MK) impressed on the at least one contact strip (3) by a frictional force (R) can be compensated by an opposing counter-moment (MG) impressed on the at least one contact strip (3) by the contact force (K). [2] Current collector (1) according to claim 1, - comprising exactly one contact strip (3), - wherein the joint arrangement (7) has exactly one axis of rotation (D) which is arranged relative to the contact strip (3) with respect to the vehicle vertical direction (Z) below its contact surface (4) and with respect to a vehicle longitudinal direction (X) in the direction of travel of the vehicle behind a line of action of a total force (F) resulting from the contact force (K) between the contact wire (2) and the contact surface (4). [3] Current collector (1) according to claim 1, - comprising two contact strips (3a, 3b) arranged one behind the other in the direction of travel (X), - wherein the joint arrangement (7) has exactly one axis of rotation (D) which is arranged between the two contact strips (3a, 3b) with respect to the vehicle longitudinal direction (X), - wherein the axis of rotation (D) relative to the contact strips (3a, 3b) is arranged below their contact surfaces (4) with respect to the vehicle vertical direction (Z) and closer to the rear contact strip (3b) in the direction of travel of the vehicle than to the front contact strip (3a) with respect to a vehicle longitudinal direction (X). [4] Current collector (1) according to claim 1, - comprising two contact strips (3a, 3b) arranged one behind the other in the direction of travel (X), - wherein the joint arrangement (7) comprises a base element (8) mounted on the support frame (6) with a first axis of rotation (D1) and a second axis of rotation (D2) arranged at a fixed distance therefrom, a front leg element (9) pivotally connected to the base element (8) about the first axis of rotation (D1), a rear leg element (10) pivotally connected to the base element (8) about the second axis of rotation (D2), and a support element (11) carrying the two contact strips (3a, 3b) with a third axis of rotation (D3) and a fourth axis of rotation (D4) arranged at a fixed distance therefrom, wherein the front leg element (9) is pivotally connected to the support element (11) about the third axis of rotation (D3) and the rear leg element (10) is pivotally connected to the support element (11) about the fourth axis of rotation (D4), - wherein the distance between the third rotation axis (D3) and the fourth rotation axis (D4) is smaller than the distance between the first rotation axis (D1) and the second rotation axis (D2). [5] Electrically or hybrid-electrically driven vehicle, in particular a heavy commercial vehicle, with a current collector (1) according to one of claims 1 to 4.

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