Road milling machine and method for controlling a road milling machine

Patent metadata

Field	Value
Publication number	US-11047096-B2
Application number	US-201916668302-A
Country	US
Kind code	B2
Filing date	Oct 30, 2019
Priority date	Oct 31, 2018
Publication date	Jun 29, 2021
Grant date	Jun 29, 2021

Abstract

A self-propelled road milling machine includes a plurality of height sensors and a controller configured to determine a cross slope of the roadway being milled. Wherein in a first leveling mode at least two sensors are longitudinally aligned and laterally spaced on one side of the milling machine, closet to the center of the road. The controller using sensor signals to adjust the cross slope of the milling drum to be parallel to the cross slope of the roadway adjacent the milling machine. Wherein in a second leveling mode the sensors are on opposite sides of the milling drum.

First claim

What is claimed is:

1. A road milling machine, comprising:
a machine frame on which a milling drum is arranged;
at least one running gear on a left side of the road milling machine in the working direction and at least one running gear on a right side of the road milling machine in the working direction;
lifting devices respectively corresponding to each of said running gears and upon which the machine frame is supported, wherein one or more of a height and an inclination of the machine frame is adjustable with respect to a driving surface by actuating of the lifting devices;
a first distance measuring device configured to measure a first distance between at least one associated reference point and the driving surface;
a second distance measuring device configured to measure a second distance between at least one associated reference point and the driving surface;
a controller configured to compare a first distance value corresponding to the first measured distance to a first prespecified distance value, to compare a second distance value corresponding to the second measured distance to a second prespecified distance value, and to generate control signals for one or more of the lifting devices according to respective deviations therefrom;
wherein in a first levelling mode for a track section on an outer side of the driving surface:
the respective reference points of the first and second distance measuring devices are each located on a first side of the milling drum closest to a centre of the driving surface, wherein the reference point of the second distance measuring device lies at a lateral distance extending from the reference point of the first distance measuring device and away from the milling drum;
the controller is configured, according to a deviation of the first distance value from the prespecified distance value, to generate control signals for the at least one lifting device corresponding to the first side of the milling drum, and
the controller is configured, according to a deviation of the second distance value from the prespecified distance value, to generate control signals for the at least one lifting device corresponding to an opposing second side of the milling drum.

2. The road milling machine of claim 1 , wherein in a second levelling mode for a track section on an inner side of the driving surface:
the first distance measuring device is configured such that its reference point lies on the left side of the milling drum in the working direction,
the second distance measuring device is configured such that its reference point lies on the right side of the milling drum in the working direction, and
the reference point of the second distance measuring device lies at a lateral distance from the reference point of the first distance measuring device on the right side of the reference point of the first distance measuring device.

3. The road milling machine of claim 2 , wherein the controller, for the second levelling mode, is configured such that
the at least one lifting device corresponding to the at least one running gear on the left side in the working direction is retracted if the first distance value is greater than the prespecified distance value,
the at least one lifting device corresponding to the at least one running gear on the left side in the working direction is extended if the first distance value is less than the prespecified distance value,
the at least one lifting device corresponding to the at least one running gear on the right side in the working direction is retracted if the second distance value is greater than the prespecified distance value, and
the at least one lifting device corresponding to the at least one running gear on the right side in the working direction is extended if the second distance value is less than the prespecified distance value.

4. The road milling machine of claim 1 , wherein:
the first and second distance measuring devices are configured such that their reference points lie on the left side of the milling drum in the working direction,
the reference point of the second distance measuring device lies at a lateral distance from the reference point of the first distance measuring device on the left side of the reference point of the first distance measuring device, and
the controller, for the first levelling mode, is configured
according to the deviation of the first distance value from the prespecified distance value, to generate control signals for the at least one lifting device corresponding to the at least one running gear on the left side in the working direction, and
according to the deviation of the second distance value from the prespecified distance value, to generate control signals for the at least one lifting device corresponding to the at least one running gear on the right side in the working direction.

5. The road milling machine of claim 4 , wherein the controller is configured, for the first levelling mode, such that
the at least one lifting device corresponding to the at least one running gear on the left side in the working direction is retracted if the first distance value is greater than the prespecified distance value,
the at least one lifting device corresponding to the at least one running gear on the left side in the working direction is extended if the first distance value is less than the prespecified distance value,
the at least one lifting device corresponding to the at least one running gear on the right side in the working direction is extended if the second distance value is greater than the prespecified distance value, and
the at least one lifting device corresponding to the at least one running gear on the right side in the working direction is retracted if the second distance value is less than the prespecified distance value.

6. The road milling machine of claim 1 , wherein:
the first and second distance measuring devices are configured such that their reference points lie on the right side of the milling drum in the working direction,
the reference point of the second distance measuring device lies at a lateral distance from the reference point of the first distance measuring device on the right side of the reference point of the first distance measuring device, and
the controller, for the first levelling mode, is configured
according to the deviation of the first distance value from the prespecified distance value, to generate control signals for the at least one lifting device corresponding to the at least one running gear on the right side in the working direction, and
according to the deviation of the second distance value from the prespecified distance value, to generate control signals for the at least one lifting device corresponding to the at least one running gear on the left side in the working direction.

7. The road milling machine of claim 6 , wherein the controller, for the first levelling mode, is configured such that
the at least one lifting device corresponding to the at least one running gear on the right side in the working direction is retracted if the first distance value is greater than the prespecified distance value,
the at least one lifting device corresponding to the at least one running gear on the right side in the working direction is extended if the first distance value is less than the prespecified distance value,
the at least one lifting device corresponding to the at least one running gear on the left side in the working direction is extended if the second distance value is greater than the prespecified distance value, and
the at least one lifting device corresponding to the at least one running gear on the left side in the working direction is retracted if the second distance value is less than the prespec

Assignees

• Wirtgen Gmbh

Inventors

• Winkels Sebastian

Classifications

• E01C19/004

  Devices for guiding or controlling the machines along a predetermined path (for graders or bulldozers E02F3/841; for other soil-shifting machines E02F9/2045) · CPC title

• E01C23/088 Primary

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