Current collector and road vehicle equipped therewith

Abstract

The invention relates to a current collector (2) for an electrically or hybrid-electrically driven road vehicle (1) for feeding traction energy from a two-pole overhead line system having one contact wire (3, 4) per contact pole. Said current collector comprises an erectable supporting rod (5) which is supported on the vehicle side via a base joint (8) on a rod base (9) and on the contact wire side carries at least one contact strip (15) per contact pole in order to electrically contact the contact wire (3, 4) assigned to the contact pole. Due to the fact that the supporting rod (5) has exactly one lower arm (6) connected to the base joint (8), exactly one upper arm (7) connected to the lower arm (6) via a knee joint (10), and exactly one cross beam (11) connected to the upper arm (7) via a support joint (12), each of the contact strips (15) being resiliently mounted on the cross member (11) via spring elements (16, 17), the design of the current collector (2) can be simplified and its contact behaviour with the overhead line system can be improved.

Description

[0001] Description

[0002] Pantograph and road vehicle equipped with such a pantograph

[0003] The invention relates to a current collector according to the preamble of patent claim 1 and to a road vehicle according to claim 7.

[0004] Such a vehicle is known, for example, from the published patent application DE 10 2017 203 046 A1. It comprises a pantograph for feeding traction energy from a two-pole overhead line system having a contact wire for each contact pole. The pantograph has a pantograph-like, directional support rod which is articulated on a rod base on the vehicle side and carries a rocker arrangement on the contact wire side. The support rod comprises a lower arm and two upper arms which are articulated to the lower arm so that they can rotate independently of one another. The rocker arrangement has a rocker frame for each of the two contact poles. Each rocker frame is articulated and connected to one of the two upper arms so that it can rotate about a transverse axis of the vehicle and carries two contact strips arranged one behind the other and parallel to the longitudinal axis of the vehicle for electrical contact with the contact wire assigned to the contact pole.

[0005] Such pantographs have a high mass, which negatively influences their vibration behavior, and a complex structure, which is associated with an increased risk of errors in operation, production and assembly.

[0006] The invention is therefore based on the object of providing a current collector of the type mentioned above with a simpler structure and improved contact behavior with the overhead line system. This object is achieved according to the invention by a current collector of the type mentioned above with the features specified in the characterizing part of patent claim 1.

[0007] A pantograph for an electrically or hybrid-electrically powered road vehicle is designed and intended to feed in traction energy from an electrical overhead line system. The road vehicle can be a heavy commercial vehicle, for example a truck or a bus. The overhead line system has two poles and has one contact wire for each contact pole. The contact wires are arranged approximately parallel to one another and at the same height above an electrified lane of a carriageway used by the road vehicle. A feed section of the overhead line system is supplied with electrical energy via a substation, which is made available to the road vehicles via the two contact wires. The pantograph comprises an erectable support rod. The support rod can, for example, be pantograph-like and can be erected by a pneumatic lifting drive.The support rod is supported on the vehicle side via a base joint on a rod base. On the contact wire side, it carries at least one contact strip for each contact pole for electrically contacting the contact wire assigned to the respective contact pole. The contact strips are aligned horizontally and transversely to a vehicle's longitudinal axis and can consist of an elongated graphite contact piece, which is fastened in a contact piece carrier. Downwardly bent contact horns can be arranged on the outer ends of the contact piece carriers.

[0008] According to the invention, the support rod has exactly one lower arm connected to the base joint, exactly one upper arm connected to the lower arm via a knee joint and exactly one cross member connected to the upper arm via a support joint. Each of the contact strips is spring-mounted on the cross member by spring elements. For example, two contact strips extending parallel to a transverse direction of the vehicle and arranged one behind the other in the longitudinal direction of the vehicle can be spring-supported on the cross member for each contact pole. By using separate contact strips for each of the two contact poles but no separate rockers, but only a common cross member, a considerable amount of moving mass of the pantograph can be saved.A further reduction in the mass of the pantograph is achieved by carrying the cross member by just one upper arm, instead of the previously known two upper arms, each of which carried a rocker assigned to a respective contact pole. By reducing the number of parts, the moving mass of the pantograph is reduced, so that contact force fluctuations caused by vertical vibrations can be compensated for more quickly. This improves the quality of the contact pressure of the contact strips on the contact wires and reduces wear on the contact strips. In addition, the smaller number of pantograph components simplifies its design, which reduces the susceptibility to errors during manufacture and operation.

[0009] In an advantageous embodiment of the current collector according to the invention, precisely one contact strip is assigned to each contact pole. This allows further savings in the moving mass of the current collector by dispensing with two contact strips per contact pole and the rocker frame supporting them. This not only further improves the vibration dynamics of the current collector but also simplifies the complexity of its structure. In this case, contact strips can preferably be used whose contact pieces have a width of at least 6 cm, measured in the longitudinal direction of the vehicle.

[0010] In a further advantageous embodiment of the current collector according to the invention, the spring elements are designed as leaf springs and / or as helical springs. Leaf and helical springs are particularly well suited for use in public roads due to their high availability of a wide variety of spring characteristics and their robustness. Two spring elements can be arranged at opposite ends of each contact strip or pair of contact strips of a contact pole. Either only leaf springs or only helical springs or a combination of leaf and helical springs can be used. The restoring force when the spring elements are compressed can be set, for example, by selecting a spring constant so that it increases linearly. A minimum initial value for the restoring force can be specified by preloading the spring elements.Likewise, stop elements, for example with a shock-absorbing effect, can limit the deflection of the spring elements and thus the deflection of the contact strips relative to the cross member. The spring constant of the spring elements is selected so that both contact strip vibrations caused by vehicle vibrations and height differences between the contact strips of different contact poles due to different contact wire heights are compensated for in order to achieve a high contact quality between the contact strips and the contact wires.

[0011] In a further advantageous embodiment of the current collector according to the invention, a spring characteristic curve of the spring elements has a first spring constant on a first compression travel and a second spring constant which is greater than the first spring constant on a subsequent second compression travel. The second compression travel is provided for an overload situation, during which damage to the current collector - for example caused by the contact strips hitting the cross member - can be cushioned by a more rapidly increasing restoring force. In order to compensate for larger height differences between the contact wires, there can be a further spring travel between the first and second compression travel, during which the restoring force, for example, remains constant. This effect can be achieved by a spring element designed as a constant force spring.The spring elements connected in this cascade form a passive and robust spring assembly with a self-centering spring characteristic. The spring assembly compensates for variations caused by both vibrational movements of the vehicle in the higher-frequency range and height differences of the contact wires in the lower-frequency range. The individual spring elements can be replaced separately, allowing for targeted adjustment of the characteristics of the individual spring stages.

[0012] In a further advantageous embodiment of the current collector according to the invention, the spring elements electrically insulate the contact strips from the cross member. The bearing points of the spring elements on the contact strips and / or on the cross member, or even the spring elements themselves, can be electrically insulating. In both cases, the spring elements can form a substantial part of the electrical insulation distance between the high-voltage level of the contact wires and the potential of the vehicle chassis. Furthermore, the rod base of the current collector can be attached to the road vehicle via electrical post insulators.

[0013] In a further advantageous embodiment of the current collector according to the invention, a mechanical bridge member is mounted on the cross member in such a way that a contact wire cannot sink between contact strips of different contact poles. The bridge member can, for example, be designed as an insulating bracket and arranged and shaped in such a way that a contact wire slipping from a contact strip in the correct center of the vehicle cannot penetrate into a gap between adjacent contact strips below the contact strips. This prevents a contact wire from becoming threaded under a contact strip and the resulting damage to the current collector or the overhead line system.

[0014] The invention further relates to an electrically or hybrid-electrically driven road vehicle, comprising a current collector according to one of claims 1 to 6. Further properties and advantages of the subject matter of the invention emerge from the following description of a concrete embodiment with reference to the drawings, in which

[0015] FIG 1 is a front view of a first embodiment of a current collector according to the invention,

[0016] FIG 2 is a side view of a second embodiment of a current collector according to the invention,

[0017] FIG 3 the current collector from FIG 1 with a spring-loaded contact strip,

[0018] FIG 4 is a front view of a third embodiment of a current collector according to the invention,

[0019] FIG 5 shows a first characteristic curve of spring elements of a current collector according to the invention, and

[0020] FIG 6 shows a second characteristic curve of spring elements of a current collector according to the invention schematically.

[0021] 1 to 4 only show a section of a vehicle frame or another vehicle part directly or indirectly supported on it of a non-track-bound, electrically or hybrid-electrically powered road vehicle 1, for example a heavy goods vehicle. The vehicle 1 has a pantograph 2 for feeding in traction energy from an electrical overhead line system. The overhead line system is of two-pole design and has contact wires 3 and 4 for each contact pole designed as forward and return conductors. The pantograph 2 has a support rod 5 which can be directed in the vertical direction Z of the vehicle and which is designed as a pantograph with a single lower arm 6 and a single upper arm 7. The support rod 5 is supported with its lower arm 6 via a base joint 8 on a rod base 9 which is firmly connected to the road vehicle 1. The upper arm 7 is connected to the forearm 6 via a knee joint 10 .The upper arm 7 is in turn connected to a cross member 11 via a support joint 12. The base joint 8, knee joint 10 and support joint 12 are designed as rotary joints whose joint axes are aligned parallel to a transverse direction Y of the road vehicle 1. A coupling rod 13 is connected to the rod base 9 and the upper arm 7 in such a way that when the lower arm 6 is erected by a lifting device (not shown), for example an air bellows, the upper arm 7 is also forcibly erected, whereby a space formed by the upper arm 7 and lower arm.

[0022] 6 enlarged to a tensioned knee angle. In addition, a guide rod 14 is articulated to the lower arm 6 and the cross member 12 in such a way that when the support rod 5 is erected, the cross member 12 is guided in such a way that spring-mounted contact strips 15 thereon remain facing the contact wires 3 and 4, respectively. At least one, preferably exactly one contact strip 15 is spring-mounted on the cross member 11 for each contact pole via spring elements 16 and 17, respectively. Via the contact strips 15, the current collector 2 contacts the contact wires 3 and 4 assigned to the respective contact pole, whereby an electrical sliding contact for energy transmission is formed while the road vehicle 1 is traveling. The contact strips 15 are aligned horizontally and transversely to a longitudinal axis X of the road vehicle 1. At their outer ends, downwardly bent run-on horns 18 are formed on the grinding strips 15.

[0023] In the embodiment shown in FIGS. 1 to 3, the upper arm

[0024] 7 T-shaped and has at its contact wire side end a crown tube 19 extending in the vehicle transverse direction Y. The cross member 11 is articulated to the crown tube 19 via support joints 12. In the embodiment according to FIG 4, the upper arm 7 is V-shaped and has at its contact wire side end a crown tube 19 extending in the vehicle transverse direction Y, in which two support joints 12 for connecting the cross member 11 are integrated.

[0025] In the embodiment according to FIGS. 1, 2 and 4, the spring elements are designed as leaf springs 16, in the embodiment according to FIGS. 2 as coil springs 17. Two spring elements 16 and 17 can be arranged at opposite ends of each contact strip 15. Either only leaf springs 16 or only coil springs can be used.

[0026] 16 or leaf springs 16 and coil springs 17 can be used in combination.

[0027] The restoring force F when the spring elements 16 or .

[0028] 17 can be set by selecting a spring constant K, for example, so that it increases linearly with increasing spring deflection S as shown in FIG 5. By preloading the spring elements 16 or 17, a minimum initial value FO for the restoring force can be specified. The spring constant K of the spring elements 16 or 17 is selected so that both contact strip vibrations induced by vehicle vibrations and height differences between different contact wire heights of the contact wires 3 and 4 are compensated for in order to achieve a high contact quality between contact strips 15 and contact wires 3 and 4.

[0029] According to FIG. 6, the spring characteristic curve KL of the spring elements 16 and 17 can have a first spring constant K1 on a first compression travel S1 and a second spring constant K2 that is greater than the first spring constant K1 on a subsequent second compression travel S2. The second compression travel S2 is intended for an overload situation, in which damage to the current collector 2 - for example, due to the contact strips 15 striking the cross member 11 - can be cushioned by a more rapidly increasing restoring force F.

[0030] The spring elements 16 and 17 electrically insulate the sliding strips 15 from the cross member 11, for example by the bearing points of the spring elements 16 and 17 on the sliding strips 15 and / or on the cross member 11 or the spring elements 16 and 17 themselves being designed to be electrically insulating.

[0031] In all embodiments, a mechanical bridge member 20 is mounted on the cross member 11 in such a way that a contact wire 3 or 4 is prevented from sinking between contact strips 15 of different contact poles. The bridge member 20 can, for example, be designed as an insulating bracket and arranged and shaped in such a way that a contact wire 3 or 4 slipping from a contact strip 15 in the correct center of the vehicle cannot penetrate into a gap ZR between adjacent contact strips 15 below the contact strips 15. This prevents a contact wire 3 or 4 from becoming threaded under a contact strip 15 and the resulting damage to the pantograph 2 or to the overhead line system.

[0032] The core of the invention is the achieved reduction in the moving mass of a current collector according to the invention, whereby fluctuating contact forces can be compensated more quickly. The improved quality of the contact force also reduces wear on the contact strips 15. The reduction in the number of components also reduces errors in the manufacture, assembly, and operation of a current collector 2 according to the invention.

Claims

Patent claims 1. Current collector (2) for an electrically or hybrid-electrically powered road vehicle (1) for supplying traction energy from a two-pole overhead contact line system having a contact wire (3, 4) for each contact pole, comprising - a support rod (5) which can be adjusted, which is supported on the vehicle side via a base joint (8) on a rod base (9) and carries at least one contact strip (15) per contact pole on the contact wire side for electrical contacting the contact wire (3, 4) assigned to the respective contact pole, characterized by this, - that the support frame (5) has exactly one forearm (6) connected to the base joint (8), exactly one upper arm (7) connected to the forearm (6) via a knee joint (10), and exactly one cross member (11) connected to the upper arm (7) via a support joint (12), - wherein each of the grinding strips (15) is resiliently mounted on the crossbeam (11) via spring elements (16, 17).

2. Current collector (2) according to claim 1, - where each contact pole is assigned exactly one sliding strip (15).

3. Current collector (2) according to any of the preceding claims, - wherein the spring elements are designed as a leaf spring (16) and / or as a coil spring (17).

4. Current collector (2) according to any of the preceding claims, - wherein a spring characteristic curve (KL) of the spring elements (16, 17) has a first spring constant (Kl) on a first compression stroke (Sl) and a second spring constant (K2) that is larger than the first spring constant (Kl) on a subsequent second compression stroke (S2).

5. Current collector (2) according to claim 3 or 4, - wherein the spring elements (16, 17) electrically insulate the sliding bars (15) against the crossbeam (11).

6. Current collector (2) according to any of the preceding claims, - wherein a mechanical bridge member (20) is mounted on the crossbeam (11) in such a way that a drop of a contact wire (3, 4) between sliding strips (15) of different contact poles is prevented.

7. Electrically or hybrid-electrically powered road vehicle (1), in particular a truck or bus, a pantograph (2) according to one of the preceding claims.

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