GRID-POWERED MATERIAL HANDLING AND/OR CONSTRUCTION MACHINE

Abstract

The present invention relates to a material handling and/or construction machine, in particular lifting gear such as a crane, comprising a plurality of electric drives for driving work assemblies and/or structural components of the material handling and/or construction machine, a control apparatus for controlling the drives, and a power supply device for supplying electric power to the electric drives, wherein the power supply device has a grid connection for connection to a power grid and drawing of the electric power from the power grid, wherein a measuring device for measuring the total electric power consumption of the material handling and/or construction machine from the power grid is provided at the grid connection at the machine-end grid connection.

Claims

1. A material handling and/or construction machine comprising a lifting gear comprising as a crane, wherein the machine comprises: a plurality of electric drives for driving work assemblies and/or structural components of the material handling and/or construction machine; a control apparatus for controlling the drives; a power supply device for supplying the electric drives with electric power, wherein the power supply device has a machine-end grid connection for connection to a power grid and drawing of the electric power from the power grid; and a measuring device at the machine-end grid connection, wherein the measuring device is configured to measuring a total electric power consumption of the material handling and/or construction machine from the power grid.

2. The material handling and/or construction machine of claim 1, wherein the control apparatus is configured to compare the total electric power consumption measured with a maximum power available from the power grid and/or a limit value dependent thereon and to reduce and/or limit the power consumption of one or more electric drives in dependence on the comparing.

3. The material handling and/or construction machine of claim 2, wherein the control apparatus is configured to scale control commands entered by a machine operator and/or generated by a machine control module for controlling the drives in dependence on the comparing and/or to limit said control commands to a reduced maximum value.

4. The material handling and/or construction machine according to claim 3, wherein the control apparatus is configured to reduce one or more driving speeds of one or more electric drives and to override a driving speed command indicating a desired driving speed greater than this.

5. The material handling and/or construction machine according to claim 2, wherein the control apparatus is configured to reduce one or more driving speeds of one or more electric drives and to override a driving speed command indicating a desired driving speed greater than this.

6. The material handling and/or construction machine according to claim 2, wherein the control apparatus is configured to switch on an energy supply storage unit in dependence on said comparing and/or to increase the power withdrawal from the energy supply storage unit for supplying the electric drives when the measured actual total power consumption of the material handling and/or construction machine reaches the maximum available power of the power grid or the limit value derived therefrom or a predetermined fraction thereof.

7. The material handling and/or construction machine of claim 1, wherein the control apparatus has an input interface for inputting a maximum available power of the power grid to be connected.

8. A material handling and/or construction machine comprising a lifting gear comprising as a crane, wherein the machine comprises: a circuit breaker at a machine-end grid connection, wherein the circuit breaker is matched to a respective power grid to be connected, via which circuit breaker the total power consumption of the material handling and/or construction machine drawn from the power grid runs.

9. The material handling and/or construction machine of claim 8, wherein the circuit breaker comprises a universal current sensitive error current circuit breaker.

10. The material handling and/or construction machine of claim 9, wherein the universal current sensitive error current breaker is configured to have multiple poles and is connected to cores of a grid supply line of the material handling and/or construction machine.

11. The material handling machine and/or construction machine of claim 10, wherein the circuit breaker has a rated residual current, wherein the circuit breaker is adjustable with respect to the rated residual current, and wherein the circuit breaker is configured to switch off upon reaching the rated residual current.

12. The material handling machine and/or construction machine of claim 8, wherein the circuit breaker has a rated residual current, wherein the circuit breaker is adjustable with respect to the rated residual current, and wherein the circuit breaker is configured to switch off upon reaching the rated residual current.

13. The material handling machine and/or construction machine of claim 9, wherein the circuit breaker has a rated residual current, wherein the circuit breaker is adjustable with respect to the rated residual current, and wherein the circuit breaker is configured to switch off upon reaching the rated residual current.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The invention is explained in more detail below with reference to a preferred embodiment and associated drawings. The drawings show:

[0025] FIG. 1: a material handling and/or construction machine in the form of a revolving tower crane according to an advantageous embodiment of the invention, which can be connected via a grid connection to a power grid present at a construction site, and

[0026] FIG. 2: a circuit diagram of the grid connection of the material handling and/or construction machine from FIG. 1, showing the measuring device provided at the grid connection and the universal current sensitive residual current circuit breaker there provided.

DETAILED DESCRIPTION

[0027] As FIG. 1 shows, the material handling and/or construction machine 1 can be configured to be a crane, in particular a revolving tower crane, which comprises a tower 2 and a jib 3 supported by it as structural components, which can be held by a bracing and balanced via a ballast weight on a counter-jib.

[0028] The material handling and/or construction machine 1 comprises several electric drives 11, 12 and 13, wherein in case of a crane this can be a slewing gear drive 11, a trolley drive 12 and a hoist drive 13. As shown in FIG. 1, a trolley 4 can be movably mounted on the said jib 3, which can be moved along the jib 3 by said trolley drive 12, wherein the trolley drive 12 can comprise an electric motor which can wind and unwind a trolley cable on a winch or drive it around in the manner of a capstan winch.

[0029] A lifting cable 6 can run from the aforementioned trolley 4, which carries a load suspension means such as for example a load hook 7. The hoist drive 13 can wind and unwind said hoist cable 6 on a winch and comprise an electric motor for driving the winch.

[0030] The jib 3 can also be driven in rotation about an upright axis, in particular the longitudinal axis of the tower, by the slewing gear drive 11. When configured as a top-slewer the jib 3 can be rotated relative to the tower 2, while with a bottom-slewer the jib 3 is rotated together with the tower 2 about the said upright axis 4.

[0031] Said electric drives in the form of slewing gear drives, trolley chassis drives and hoist drives 11, 12 and 13 are controlled by a control apparatus 8, wherein the control apparatus 8 may be configured to be electronic and may have a microprocessor and a program memory connected thereto. In particular, the control apparatus 8 can implement control commands which a crane driver in the driver's cab 9 can input via suitable input means such as joysticks and the like.

[0032] A power supply device 10 for supplying the said electric drives 11, 12, 13 with electric power comprises a grid connection 14, through which the material handling and/or construction machine 1 can draw electric power from a power grid 15, which supplies the spatial area of a respective construction site or a respective assembly site or operating site and can, for example, be the supply grid of the respective utility company.

[0033] Said grid connection 14 may in particular comprise a multi-pole power plug which can be connected to a socket or a complementary connector of the power grid 15.

[0034] At the grid connection 14 or a point of the machine-end circuit through which the total power consumption of the material handling and/or construction machine 1 flows from the grid connection 14, the material handling and/or construction machine 1 has a measuring device 16 for measuring the total electric power consumption from the power grid 15, see FIG. 1 and FIG. 2. If the grid supply line 17 is usually multi-pole, for example four-pole, the measuring device 16 can be connected to the cores of the supply line 17, see FIG. 2, and measure the total current flow through the grid supply line 7. The measuring device 16 can measure the power consumption in various ways, for example by measuring the current flow and/or the voltage, and can comprise suitable measuring modules for this purpose, see FIG. 2.

[0035] Furthermore, a circuit breaker 18 is provided at the grid connection 14 of the material handling and/or construction machine 1 or at the measuring device 16 and/or at a point of the machine-end grid connection through which the total power consumption passes, which may comprise a universal current sensitive residual current circuit breaker. Such a universal current sensitive residual current circuit breaker 18 can, for example, be configured to have four poles, see FIG. 2, so that it can be connected to the four-pole grid supply line 17 and, if necessary, be configured to be converter-fixed.

[0036] The measuring signal of the measuring device 16, which indicates the total current power consumption of the machine 1, is advantageously provided to the control apparatus 8, which can compare the total power consumption with a limit value that can be determined in dependence on the maximum available power of the respective power grid 15, for example equated with the maximum available grid power or set to a predetermined fraction thereof. The said limit value in dependence on the maximum available power of the power grid 15 can advantageously be provided via an input interface of the control apparatus 8.

[0037] The control apparatus 8 is advantageously configured to compare the current actual, measured power consumption of the machine 1 with the maximum available power or said limit value, which was input via the input interface, in order to provide a power reduction for the electric drives 11, 12, 13 in the manner described at the beginning, if necessary.

[0038] Alternatively or additionally, the control apparatus 8 can also connect an energy supply storage unit 19 of the power supply device 10 and/or increase the power draw from such a storage unit in order to prevent an overload of the power grid 15. Such an energy supply storage unit 19 may comprise a battery cell and/or a capacitor or several groups or mixed forms thereof, wherein the energy storage unit 19 may be provided independently thereof on the material handling and/or construction machine 1. If necessary, a separate energy supply storage unit, for example in the form of a storage container, can also be provided at the assembly site of the machine and connected to the machine.