Road milling machine for the treatment of road pavements, as well as method for pivoting a travelling drive unit of a road milling machine

Patent metadata

Field	Value
Publication number	US-9540779-B2
Application number	US-201514749849-A
Country	US
Kind code	B2
Filing date	Jun 25, 2015
Priority date	Aug 22, 2012
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

A road milling machine includes a rear wheel or track mounted on a pivot arm such that the wheel or track is movable between a first outer end position projecting laterally relative to the machine frame, and a second inner end position which permits milling close to an edge. A travel drive of the rear wheel or track provides a driving force to move the wheel or track between the end positions.

First claim

What is claimed is:

1. A road milling machine for the treatment of a ground surface, comprising:
a machine frame;
a plurality of lifting columns configured to adjust a height of the machine frame, including at least first and second rear lifting columns, the first rear lifting column having a longitudinal axis;
a plurality of ground engaging units, including first and second rear ground engaging units, the first and second rear ground engaging units arranged at lower ends of the first and second rear lifting columns, respectively, at least the first rear ground engaging unit including a travel drive;
a working drum connected to the machine frame and rotatable about a drum axis of the working drum;
a pivot arm connected to the first rear lifting column and pivotally connected to the machine frame to pivot about a pivotal axis parallel to the longitudinal axis of the first rear lifting column, such that the pivot arm transfers the first rear ground engaging unit between a first outer end position projecting laterally relative to the machine frame and a second inner end position;
a steering assembly configured to adjust a steering angle of the first rear ground engaging unit;
a controller configured to control operation of the travel drive and the steering assembly; and
the first rear ground engaging unit and the pivot arm being configured such that there is no separate driving device for the pivot arm, and the travel drive of the first rear ground engaging unit provides a driving force for pivoting of the pivot arm and the first rear ground engaging unit between the first outer end position and the second inner end position with the first rear ground engaging unit being in permanent contact with the ground surface during pivoting.

2. The road milling machine of claim 1 , wherein:
the controller is configured such that the control of the operation of the travel drive and the steering assembly are coordinated so that the operation of the travel drive and the operation of the steering assembly occurs at least in part simultaneously.

3. The road milling machine of claim 2 , wherein:
the rear ground engaging units are tracked ground engaging units.

4. The road milling machine of claim 1 , wherein:
the controller is configured such that the control of the operation of the travel drive and the steering assembly are sequential.

5. The road milling machine of claim 4 , wherein:
the controller is configured to control the transfer of the first rear ground engaging unit from the first outer end position to the second inner end position by driving the steering assembly until the first rear ground engaging unit is aligned essentially orthogonal to the pivot arm, then driving the travel drive in order to pivot the pivot arm to the second inner end position, and then driving the steering assembly to readjust the first rear ground engaging unit to a straight ahead steering position.

6. The road milling machine of claim 1 , wherein the travel drive of the first rear ground engaging unit and the steering assembly are configured such that the first rear ground engaging unit is transferable on a circular arc from the first outer end position to the second inner end position and back while being in permanent contact with the ground surface.

7. The road milling machine of claim 1 , wherein the first rear lifting column is coupled to the machine frame only by the pivot arm, said pivot arm being a single pivot arm.

8. The road milling machine of claim 1 , wherein:
the steering assembly is configured to adjust the steering angle about a steering axis co-axial with the longitudinal axis of the first rear lifting column.

9. The road milling machine of claim 1 , further comprising:
at least a first lock configured to lock the first rear lifting column in one of the end positions.

10. The road milling machine of claim 1 , wherein:
the first rear lifting column includes an upper part fixed in longitudinal direction relative to the machine frame, and a telescopically extendable lower part, the first rear ground engaging unit being attached to a lower end of the lower part, the steering assembly being coupled to the extendable lower part.

11. The road milling machine of claim 1 , wherein:
the travel drive of the first rear ground engaging unit maintains a same direction of travel in both end positions.

12. The road milling machine of claim 1 , wherein:
the travel drive of the first rear ground engaging unit is the only available driving force for pivoting the pivot arm.

13. A road milling machine for the treatment of a ground surface, comprising:
a machine frame;
a plurality of lifting columns configured to adjust a height of the machine frame, including at least first and second rear lifting columns, the first rear lifting column having a longitudinal axis;
a plurality of ground engaging units, including first and second rear ground engaging units, the first and second rear ground engaging units arranged at lower ends of the first and second rear lifting columns, respectively, at least the first rear ground engaging unit including a travel drive;
a working drum connected to the machine frame and rotatable about a drum axis of the working drum;
a pivot arm connected to the first rear lifting column and pivotally connected to the machine frame to pivot about a pivotal axis parallel to the longitudinal axis of the first rear lifting column, such that the pivot arm transfers the first rear ground engaging unit between a first outer end position projecting laterally relative to the machine frame and a second inner end position;
a steering assembly configured to adjust a steering angle of the first rear ground engaging unit; and
a controller configured to control operation of the travel drive such that the travel drive of the first rear ground engaging unit provides a driving force for pivoting of the pivot arm and the first rear ground engaging unit with the first rear ground engaging unit being in permanent contact with the ground surface during pivoting.

14. The road milling machine of claim 13 , wherein:
the controller is configured to also control operation of the steering assembly.

15. The road milling machine of claim 14 , wherein:
the controller is configured such that the control of the operation of the travel drive and the steering assembly are coordinated so that the operation of the travel drive and the operation of the steering assembly occurs at least in part simultaneously.

16. The road milling machine of claim 15 , wherein:
the rear ground engaging units are tracked ground engaging units.

17. The road milling machine of claim 14 , wherein:
the controller is configured such that the control of the operation of the travel drive and the steering assembly are sequential.

18. The road milling machine of claim 17 , wherein:
the controller is configured to control the transfer of the first rear ground engaging unit from the first outer end position to the second inner end position by driving the steering assembly until the first rear ground engaging unit is aligned essentially orthogonal to the pivot arm, then driving the travel drive in order to pivot the pivot arm to the second inner end position, and then driving the steering assembly to readjust the first rear ground engaging unit to a straight ahead steering position.

19. The road milling machine of claim 13 , wherein the travel drive of the first rear ground engaging unit and the steering assembly are configured such that the first rear ground engaging unit is trans

Assignees

• Wirtgen Gmbh

Inventors

• Berning Christian
• Stinner Tobias
• Vogt Andreas
• Barimani Cyrus
• Hähn Günter

Classifications

• E01C23/088 Primary

  Rotary tools, e.g. milling drums {(for forming recesses to receive marking materials E01C23/0946)} · CPC title

• B62D11/20

  Endless-track steering having pivoted bogie carrying track (B62D11/02 takes precedence) · CPC title

• B62D7/04

  with more than one wheel · CPC title

• B60G2300/40

  Variable track or wheelbase vehicles · CPC title

• B60G2300/09

  Construction vehicles, e.g. graders, excavators · CPC title