Tower crane with a detection of a rotating part autorotation or oscillation state in an out of service configuration

Patent metadata

Field	Value
Publication number	US-11560293-B2
Application number	US-202117369919-A
Country	US
Kind code	B2
Filing date	Jul 7, 2021
Priority date	Jul 7, 2020
Publication date	Jan 24, 2023
Grant date	Jan 24, 2023

Abstract

A tower crane includes a tower on which a rotating portion is pivotally mounted and configurable between a service configuration in which the rotating portion can be rotatably driven by a motorized orientation system, and an out of service configuration in which the rotating portion is rotatably released to be able to be oriented in the direction of the wind. A control/command unit activates a monitoring mode in the out of service configuration to detect, depending on variations in the angle of orientation or the angular speed of the rotating portion, if the rotating portion is in one of the following movement states: an autorotation state corresponding to a rotary movement of the rotating portion in a given direction over at least one complete turn; or an oscillation state corresponding to a back and forth movement of the rotating portion about the orientation axis.

First claim

The invention claimed is:

1. A tower crane comprising:
a tower on which a rotating portion is pivotally mounted along an orientation axis by a pivot mechanism, the pivot mechanism including at least a motorized orientation system, a mechanical orientation brake and an angular detector configured to detect an orientation angle of the rotating portion, wherein the tower crane is configurable between a service configuration in which the rotating portion is rotatably driven on the tower along the orientation axis by the motorized orientation system, and an out of service configuration in which the rotating portion is rotatably released on the tower according to the orientation axis for orientation in a direction corresponding to a wind direction, the mechanical orientation brake being deactivated in the out of service configuration;
a control/command unit connected to the motorized orientation system, the mechanical orientation brake and the angular detector, wherein, in the out of service configuration, the control/command unit activates a monitoring mode in which the control/command unit detects, as a function of variations in the angle of orientation of the rotating portion or as a function of variations of an angular speed of the rotating portion established from the variations of the orientation angle, if the rotating portion is in one of the following movement states:
an autorotation state corresponding to a rotary movement of the rotating portion in a given direction over at least one complete turn, wherein a variation of the orientation angle according to an angular amplitude is at least greater than one angular autorotation threshold of at least 360 degrees in a first given time interval or at an angular speed greater than a given autorotation speed threshold, and
an oscillation state corresponding to a back and forth movement of the rotating portion about the orientation axis, wherein at least one cycle of variations of the angle of orientation includes movement of the rotating portion in a first direction then in a second direction, opposite to the first direction, and wherein an angular displacement of the orientation angle is at least equal to an angular oscillation threshold comprised between 20 and 180 degrees in a given second time interval or at an angular speed greater than a given oscillation speed threshold.

2. The tower crane according to claim 1 , wherein, in the service configuration, the control/command unit deactivates the monitoring mode.

3. The tower crane according to claim 1 , comprising at least one anemometer for measuring a wind speed, the anemometer connected to the control/command unit, and in which, in the monitoring mode, the control/command unit detects a movement state also depending on the wind speed.

4. The tower crane according to claim 3 , wherein, in the monitoring mode, if a movement state is detected, then the control/command unit records a movement event defined by a recording of a dating of the movement state and of one or more movement parameters chosen from: variations in the angle of orientation, angular speeds or at least a maximum angular speed during the movement state, the angular amplitude for the autorotation state, and the angular displacement for the oscillation state, and
wherein, in the monitoring mode, if a movement state is detected, then the control/command unit registers in the movement event also changes in wind speed or average wind speed or maximum wind speed during the movement state.

5. The tower crane according to claim 3 , wherein, in the monitoring mode, the control/command unit detects whether the movement state corresponds to one of the following high movement states:
an autorotation state in which the angular amplitude is greater than a high angular autorotation threshold in the first given time interval, the high angular autorotation threshold being greater than the angular autorotation threshold; and
an autorotation state in which the angular speed is greater than a high autorotation speed threshold, the high autorotation speed threshold being greater than the autorotation speed threshold,
wherein when one of the high movement states is detected, then the control/command unit triggers at least one alert action, and
wherein another high movement state corresponds to an autorotation state in which the angular speed is between the autorotation speed threshold and the high autorotation speed threshold, and the wind speed is above a high wind speed threshold.

6. The tower crane according to claim 5 , wherein the high wind speed threshold is between 10 and 20 m/s.

7. The tower crane according to claim 6 , wherein the high wind speed threshold is between 14 and 20 m/s.

8. The tower crane according to claim 1 , wherein, in the monitoring mode, if a movement state is detected, then the control/command unit records a movement event defined by a recording of a dating of the movement state and of one or more movement parameters chosen from:
variations in the angle of orientation;
angular speeds or at least a maximum angular speed during the movement state;
the angular amplitude for the autorotation state; and
the angular displacement for the oscillation state.

9. The tower crane according to claim 8 , wherein the control/command unit triggers a transmission to a third party of a preventive message containing the movement event.

10. The tower crane according to claim 1 , wherein, in the monitoring mode, the control/command unit detects whether the movement state corresponds to one of the following high movement states:
an autorotation state in which the angular amplitude is greater than a high angular autorotation threshold in the first given time interval, the high angular autorotation threshold being greater than the angular autorotation threshold; and
an autorotation state in which the angular speed is greater than a high autorotation speed threshold, the high autorotation speed threshold being greater than the autorotation speed threshold,
wherein, when such a high movement state is detected, then the control/command unit triggers at least one alert action.

11. The tower crane according to claim 10 , wherein the alert action comprises an activation of a sound or light local alarm.

12. The tower crane according to claim 10 , wherein the alert action comprises transmitting an alarm message to a remote entity.

13. The tower crane according to claim 10 , wherein the alert action comprises a transmission to a third party of a warning message informing of a detection of a critical instability state.

14. The tower crane according to claim 10 , wherein the alert action comprises activating the mechanical orientation brake.

15. The tower crane according to claim 10 , wherein the alert action comprises an activation of the motorized orientation system to generate a braking torque opposite to the rotation of the rotating portion.

16. A method for monitoring a tower crane comprising a tower on which a rotating portion is pivotally mounted along an orientation axis by of a pivot mechanism, the pivot mechanism including at least a motorized orientation system, a mechanical orientation brake and an angular detector configured to detect an orientation angle of the rotating portion, wherein the tower crane is configurable between a service configuration in which the rotating portion is rotatably driven on the tower along the orientation axis by the motorized orientation system, and an out of service configuration in which the rotating portion is rotatably released on the tower along the orientation axis for orientation in a direction correspon

Assignees

• Manitowoc Crane Group France

Inventors

• Mathe Denis

Classifications

• B66C23/905 Primary

  electrical · CPC title

• B66C23/022

  Pivot axis common with column · CPC title

• B66C2700/084

  Protection measures · CPC title

• B66C23/94

  for limiting slewing movements · CPC title

• B66C23/84

  Slewing gear (anti-friction bearings F16C) · CPC title