WORK MACHINE COMPRISING AN ELECTRIC TRACTION DRIVE

Abstract

The disclosure relates to a work machine, in particular a duty-cycle crawler crane, having an undercarriage which comprises a middle part and at least one crawler carrier connected to the middle part and having at least one electric traction drive, wherein at least one energy transmission line for supplying power to the traction drive and at least one further supply line runs between the traction drive and the middle part. According to the disclosure, the at least one energy supply line and the at least one further supply line run together in a separate protection means outside the middle part and the crawler carrier.

Claims

1. Work machine, having an undercarriage which comprises a middle part and at least one crawler carrier connected to the middle part and having at least one electric traction drive, wherein at least one energy transmission line for supplying power to the traction drive and at least one further supply line runs between the traction drive and the middle part, wherein the at least one energy supply line and the at least one further supply line run together in a separate protection means outside the middle part and the crawler carrier.

2. Work machine according to claim 1, wherein the protection means is configured to be flexible at least in sections, wherein at least one guide element for guiding the flexible protection means is arranged on the middle part and/or on the crawler carrier.

3. Work machine according to claim 1, wherein the protection means comprises an energy chain and/or a hose jacket.

4. Work machine according to claim 1, wherein the protection means completely surrounds the at least one energy transmission line and the at least one further supply line.

5. Work machine according to claim 1, wherein the lines running inside the protection means have connections via which they can be detached from connections on the middle part side and/or on the traction drive side.

6. Work machine according to claim 5, wherein the connections for making and disconnecting the connections are accessible from outside the middle part and/or crawler carrier and, are arranged outside the middle part and/or crawler carrier in the connected state.

7. Work machine according to claim 1, wherein at least one further supply line is a coolant line for providing coolant for the traction drive.

8. Work machine according to claim 1, wherein at least one further supply line is a signal line for transmitting control signals to the traction drive and/or sensor signals to a controller.

9. Work machine according to claim 1, wherein at least two energy supply lines are provided for supplying power to the traction drive.

10. Work machine according to claim 1, wherein the at least one energy supply line connects the traction drive to an inverter, which is arranged in the middle part of the undercarriage.

11. Work machine according to claim 1, wherein the cable routing of the protection means is adaptable to a machine configuration of the work machine.

12. Work machine according to claim 1, comprising at least two crawler carriers which are connected to the middle part and which each have at least one traction drive whose at least one energy transmission line and at least one further supply line run to the middle part in a separate protection means.

13. Work machine according to claim 1, wherein the work machine is a duty-cycle crawler crane.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0026] Further features, details and advantages of the disclosure will be apparent from the exemplary embodiment explained below with reference to the Figures. Shown are in:

[0027] FIG. 1: A side view of undercarriage and superstructure of the work machine according to the disclosure in accordance with a preferred exemplary embodiment;

[0028] FIG. 2: a perspective view of the undercarriage of the work machine according to FIG. 1; and

[0029] FIG. 3: a schematic illustration of the protection means with motor lines running inside it.

DETAILED DESCRIPTION

[0030] FIG. 1 shows a preferred exemplary embodiment of the work machine 10 according to the disclosure in a side view. The exemplary embodiment shown is a duty-cycle crawler crane 10 with a mobile undercarriage 12 and a superstructure 14 rotatably mounted on the undercarriage 12 about a vertical axis of rotation. FIG. 2 shows the undercarriage 12 in a perspective view. The boom of the duty-cycle crawler crane 10 is not shown here. The superstructure 14 has a driver's cab 17 and is rotatably connected to a middle part 13 of the undercarriage 12 via a slewing ring 15, which can be seen in FIG. 2.

[0031] Two crawler tracks 20 are attached to the side of the middle part 13 so that the middle part 13 is placed centrally between the crawler carriers 20 of the crawler chassis. The crawler carriers 20 have electric traction drives 22 which drive the crawler tracks and whose position is indicated by arrows in FIG. 2. The traction drives 22 are, in particular, electric motors.

[0032] The electric traction drives 22 are supplied and controlled from the middle part 13. For this purpose, three energy supply lines 40 in the form of AC phase cables are provided for each traction drive 22 in the exemplary embodiment shown here, which supply the respective traction drive 22 with power from the HV vehicle electrical system. The energy supply lines 40 run between the traction drives 22 and an inverter (not shown), which is arranged in the middle part 13.

[0033] Furthermore, the traction drives 22 are controlled via one or more control lines 42. Communication with the traction drives 22 can also be handled by the inverter or a separate control element. In addition, one or more signal lines 42 may be provided, for example to transmit sensor signals from the traction drives 22 to a controller (or the inverter) in the middle part 13. Finally, the traction drives 22 are preferably cooled. For this purpose, each traction drive 22 can be connected to a cooling circuit, with two coolant lines 44 running between the middle part 13 and each of the traction drives 22, which supply the coolant to the traction drives 22 and convey the heated coolant back to the middle part 13. These lines 42, 44, which are provided in addition to the energy supply lines 40, are referred to herein as additional supply lines 42, 44. All lines 40, 42, 44 together, which run between the traction drives 22 and the middle part 13, are referred to herein in abbreviated form as motor lines 40, 42, 44.

[0034] In this exemplary embodiment, the inverter preferably handles both communication with the traction drives 22 and modulation of current and voltage to power the traction drives 22.

[0035] The precise configuration of the power supply system or the power electronics of the work machine 10 for supplying the traction drives 22 is not relevant to the disclosure and depends on the configuration of the traction drives 22.

[0036] The motor lines 40, 42, 44 must be routed from the middle part 13 to the traction drives 22 on the crawler carriers 20. In the prior art, this is for example achieved by routing the lines within the steel structure of the undercarriage 12 into the crawler carriers 20 and further on to the traction drives 22. Although this provides good mechanical protection of the motor lines 40, 42, 44 from damage and soiling, it also results in longer cable lengths and makes mounting/demounting of the crawler carriers 20 more difficult due to the limited accessibility of the motor lines 40, 42, 44.

[0037] For this reason, a different approach is taken in the case of the work machine 10 according to the disclosure. Here, the motor lines 40, 42, 44 are routed outside the steel structure of the undercarriage 12 directly from the middle part 13 to the traction drives 22. In order to provide the necessary mechanical protection, the motor lines 40, 42, 44 run inside special-purpose protection means 30 that extend between the middle part 13 and the crawler carriers 20 in the area of the traction drives 22. The protection means 30 are not part of the steel structure of the undercarriage 12.

[0038] In addition, the protection means 30 are in particular designed to be flexible, i.e. they are movable. This allows the cable routing to be varied. For this purpose, the protection means 30 can be designed at least in sections, for example, as energy chains or hoses (or as a combination thereof) consisting of several links connected to each other in an articulated manner. Preferably, the entire length of the protection means 30 between the middle part 13 and the crawler carrier 20 is configured to be flexible.

[0039] In the exemplary embodiment shown here, the protection means 30 are configured as a hose jacket inside which the motor lines 40, 42, 44 run, cf. FIG. 2. Compared to the conventional solution of routing the motor lines 40, 42, 44 from the middle part 13 centrally into the crawler carriers 20 and then along the longitudinal axis of the crawler carriers 20 to the traction drives 22, this results in considerably shorter cable lengths.

[0040] FIG. 3 schematically shows an exemplary embodiment of the flexible protection means 30 with the motor lines 40, 42, 44 running therein, in this case three energy supply lines 40, a control/signal line 44 and two coolant lines 42.

[0041] Preferably, the energy supply lines 40 and the control/signal line 44 each comprise electrical connectors or connections 50, in fact, preferably at both ends, so that they can be disconnected from the connections on the traction drive 22 and the inverter in a fast and simple manner. Alternatively, common connections could also be provided at the ends of the protection means 30 (for example, according to the principle of a multi-coupling), which include the respective connections for the motor lines 40, 42, 44.

[0042] As can be seen in FIG. 2, the duty-cycle crawler crane 10 shown here has a central ballast 16 mounted on the middle part 13 at the front and rear between each of the crawler carriers 20. This can preferably be optionally attached or detached, depending on the application. Due to the flexible protection means 30, the routing of the motor lines 40, 42, 44 can thus be adapted to the mounting condition of the central ballast 16. Also, the external routing of the motor lines 40, 42, 44 makes it easy to reach their connections 50, which considerably facilitates the mounting/demounting of the crawler carriers 20.

[0043] In summary, the flexible protection means 30 result in the following advantages:

[0044] The direct and external routing of the motor lines 40, 42, 44 of the traction drives 22 provides easy accessibility.

[0045] The easy accessibility allows for mounting/demounting the motor lines 40, 42, 44 on the traction drive 22 or on the inverter in a simple manner. This means that the traction drives 22 can be quickly and easily decoupled from the motor lines 40, 42, 44 during mounting/demounting due to transport.

[0046] Due to the flexibility of the protection means 30, the cable routing can be adapted to the current machine configuration, for example the presence of a central ballast 16 or according to the assembly state.

[0047] The motor lines 40, 42, 44 can be routed in the external area of the work machine 10 in a protected manner. The flexible protection means 30 ensures mechanical protection for the motor lines 40, 42, 44.

[0048] Compared to the prior art, this results in shorter cable lengths between traction drive 22 and inverter for all motor lines 40, 42, 44, which has a positive effect on the signal transmission quality, in particular in the case of resolver cables.

LIST OF REFERENCE CHARACTERS

[0049] 10 Work machine [0050] 12 Undercarriage [0051] 13 Middle part [0052] 14 Superstructure [0053] 15 Slewing ring [0054] 16 Central ballast [0055] 17 Driver's cab [0056] 20 Crawler carrier [0057] 22 Traction drive [0058] 30 Protection means [0059] 40 Energy supply line [0060] 42 Signal/control line [0061] 44 Coolant line [0062] 50 Connections