Lifting device, in particular a mobile crane or a cable-operated excavator, having an apparatus for monitoring the raising and lowering procedures of a boom system and corresponding method

Patent metadata

Field	Value
Publication number	US-10850953-B2
Application number	US-201816012223-A
Country	US
Kind code	B2
Filing date	Jun 19, 2018
Priority date	Jun 19, 2017
Publication date	Dec 1, 2020
Grant date	Dec 1, 2020

Abstract

The invention relates to a lifting device, in particular a mobile crane or a cable-operated excavator, having an apparatus for monitoring the raising and lowering procedures of a boom system of the lifting device.

First claim

The invention claimed is:

1. A lifting device ( 1 ), having an apparatus for monitoring raising and lowering procedures of a boom system of the lifting device ( 1 ), the apparatus comprising
a device for detecting loads increasing an overturning moment of the lifting device ( 1 );
a device for detecting loads stabilizing or reducing the overturning moment of the lifting device ( 1 );
a control unit configured to calculate a limit holding force (FGrenz) for a holding line of the boom system of the lifting device ( 1 ) from the detected loads; and
a device for detecting actual holding force of the holding line,
wherein the control unit is configured to compare the limit holding force (FGrenz) and the actual holding force.

2. A lifting device ( 1 ) in accordance with claim 1 , wherein the control unit is configured to output at least one signal in dependence on the comparison between the limit holding force (FGrenz) and the actual holding force.

3. A lifting device ( 1 ) at least in accordance with claim 2 , wherein the at least one signal is a representation of the current utilization with respect to permitted utilization for a machine operator on a monitor of the lifting device and/or for stopping a movement of the lifting device ( 1 ).

4. A lifting device ( 1 ) in accordance with claim 1 , wherein the device for detecting the loads increasing the overturning moment, detects the weight of the boom system and the wind force on a boom system of the lifting device ( 1 ).

5. A lifting device ( 1 ) in accordance with claim 1 , wherein the device for detecting the loads stabilizing or reducing the overturning moment, detects the weight of a carrier unit of the lifting device.

6. A lifting device ( 1 ) in accordance with claim 1 , wherein a sensor system for detecting the current geometry of the lifting device ( 1 ) is provided; and the control unit is a control computer of the lifting device ( 1 ) or an external computer.

7. A lifting device ( 1 ) in accordance with claim 1 , wherein the device for detecting the actual holding force of the holding line, comprises at least one force measurement tab and/or at least one force measurement axis.

8. A lifting device ( 1 ) in accordance with claim 1 , wherein the control unit is configured to calculate the loads increasing the overturning moment simultaneously for a wide range of positions of the boom system in addition to current position of the boom system.

9. A lifting device ( 1 ) in accordance with claim 1 , wherein the control unit is configured not to stop a movement or a direction of movement of the lifting device ( 1 ) as long as the limit holding force (FGrenz) is not exceeded or to selectively release the movement or the direction of movement again after a stop due to an exceeding of the limit load, when maximum permitted load at a lifting hook hook increases with the direction of movement.

10. A lifting device ( 1 ) in accordance with claim 1 , which is a mobile crane or a cable-operated excavator.

11. A method of monitoring the raising and lowering procedures of a boom system of a lifting device ( 1 ), comprising the steps of:
detecting loads increasing overturning moment of the lifting device ( 1 );
detecting the loads stabilizing or reducing the overturning moment of the lifting device ( 1 );
calculating a limit holding force (FGrenz) for a holding line of a main boom ( 2 ) of the lifting device ( 1 ) from the detected loads, by a control unit;
detecting actual holding force of the holding line; and
comparing the limit holding force (FGrenz) and the actual holding force by the control unit.

12. A method in accordance with claim 11 , wherein the lifting device ( 1 ) is a mobile crane or a cable-operated excavator.

Assignees

• Liebherr Werk Nenzing

Inventors

• Mietschnig Walter
• Schapler Manfred
• Klimmer Thomas
• Eder Mathias
• Stenech Martin

Classifications

• B66C23/90 Primary

  Devices for indicating or limiting lifting moment · CPC title

• B66C23/34

  Self-erecting cranes, i.e. with hoisting gear adapted for crane erection purposes · CPC title

• B66C13/16

  Applications of indicating, registering, or weighing devices (in crane hooks B66C1/40; in safety gear B66C15/00; weighing-apparatus G01G; remote indicating in general G08) · CPC title

• B66F17/006

  for working platforms · CPC title

• B66C23/905 Primary

  electrical · CPC title