Milling machine having automatic grade control system

Patent metadata

Field	Value
Publication number	US-10640933-B2
Application number	US-201816136457-A
Country	US
Kind code	B2
Filing date	Sep 20, 2018
Priority date	Sep 22, 2017
Publication date	May 5, 2020
Grant date	May 5, 2020

Abstract

A milling machine includes a milling assembly having a housing to which left and right end gates are attached, a controller, a right front lifting column, a left front lifting column and a rear lifting column. Elevation sensors are located at the front and rear of each of the end gates. The controller is operatively attached to the elevation sensors and to linear actuators within the lifting columns of the milling machine. The elevation sensor that is located at the front end of the right end gate will provide feedback to control the position of the right front lifting column, and the elevation sensor that is located at the front end of the left end gate will provide feedback to control the position of the left front lifting column. The elevation sensors that are located at the rear ends of the end gates are available, as selected by the operator, to provide feedback to control the positions of one of the right and left front lifting columns, as well as the rear lifting column.

First claim

What is claimed is:

1. A milling machine for milling a roadway surface as operated by an operator, said milling machine comprising:
(a) a frame;
(b) a milling assembly comprising a drum housing having a right side and a left side and being attached to the frame, said milling assembly including:
(i) a right end gate having a front end and a rear end and being attached to the right side of the housing, said right end gate being adapted to be moved vertically with respect to the housing;
(ii) a right front elevation sensor that is attached to the right end gate and is adapted to determine an elevation of the front end of the right end gate with respect to the frame of the milling machine;
(iii) a right rear elevation sensor that is attached to the right end gate and is adapted to determine an elevation of the rear end of the right end gate with respect to the frame of the milling machine;
(iv) a left end gate having a front end and a rear end and being attached to the left side of the housing, said left end gate being adapted to be moved vertically with respect to the housing;
(v) a left front elevation sensor that is attached to the left end gate and is adapted to determine an elevation of the front end of the left end gate with respect to the frame of the milling machine;
(vi) a left rear elevation sensor that is attached to the left end gate and is adapted to determine an elevation of the rear end of the left end gate with respect to the frame of the milling machine;

(c) a right front lifting column that is attached at its upper end to the frame and at its lower end to a right front drive assembly, said right front lifting column including a right front linear actuator which can be operated to raise and lower the frame of the machine with respect to the roadway surface;
(d) a left front lifting column that is attached at its upper end to the frame and at its lower end to a left front drive assembly, said left front lifting column including a left front linear actuator which can be operated to raise and lower the frame with respect to the roadway surface;
(e) a rear lifting column that is attached at its upper end to the frame and at its lower end to a rear drive assembly, said rear lifting column including a rear linear actuator which can be operated to raise and lower the frame of the machine with respect to the roadway surface;
(f) a controller that is:
(i) operatively attached to the right front elevation sensor and is adapted to receive a right front end gate signal indicative of the elevation of the front end of the right end gate with respect to the roadway surface;
(ii) operatively attached to the right rear elevation sensor and is adapted to receive a right rear end gate signal indicative of the elevation of the rear end of the right end gate with respect to the roadway surface;
(iii) operatively attached to the left front elevation sensor and is adapted to receive a left front end gate signal indicative of the elevation of the front end of the left end gate with respect to the roadway surface;
(iv) operatively attached to the left rear elevation sensor and is adapted to receive a left rear end gate signal indicative of the elevation of the rear end of the left end gate with respect to the roadway surface;
(v) operatively attached to the right front linear actuator of the right front lifting column and is adapted to control the elevation of the right front lifting column with respect to the roadway surface;
(vi) operatively attached to the left front linear actuator of the left front lifting column and is adapted to control the elevation of the left front lifting column with respect to the roadway surface;
(vii) adapted to receive a side selection signal from the operator selecting either the left side or the right side of the milling machine;
(viii) adapted to receive a cut depth signal from the operator selecting a desired cut depth;
(ix) adapted to determine an actual right front cut depth on the right side of the milling machine using the right front end gate signal;
(x) adapted to determine an actual right rear cut depth on the right side of the milling machine using the right rear end gate signal;
(xi) adapted to determine an actual left front cut depth on the left side of the milling machine using the left front end gate signal;
(xii) adapted to determine an actual left rear cut depth on the left side of the milling machine using the left rear end gate signal;
(xiii) adapted to control the linear actuator in the front lifting column on the side that is not selected by the operator by averaging the actual front cut depth and the actual rear cut depth on the un-selected side of the machine and using this average to adjust the elevation of the front lifting column on the un-selected side to maintain the desired cut depth;
(xiv) adapted to control the linear actuator in the front lifting column on the selected side by using the actual front cut depth of the selected side of the machine to adjust the elevation of the front lifting column on the selected side to maintain the desired cut depth.

2. The milling machine of claim 1 :
(a) which includes:
(i) a right front elevation sensor that is associated with the right front lifting column and is adapted to determine a right front elevation of the frame with respect to the roadway surface;
(ii) a left front elevation sensor that is associated with the left front lifting column and is adapted to determine a left front elevation of the frame with respect to the roadway surface;

(b) wherein the controller is:
(i) operatively attached to the right front elevation sensor of the right front lifting column and is adapted to receive a right front lifting column signal indicative of the right front elevation of the frame with respect to the roadway surface;
(ii) operatively attached to the left front elevation sensor of the left front lifting column and is adapted to receive a left front lifting column signal indicative of the left front elevation of the frame with respect to the roadway surface.

3. The milling machine of claim 1 wherein:
(a) the housing comprises:
(i) a left side enclosure having an outer side to which a pair of left side guide bolts are attached;
(ii) a right side enclosure having an outer side to which a pair of right side guide bolts are attached;

(b) the left end gate includes a pair of left side guide slots that are engaged by the left side guide bolts to provide a measure of control for vertical adjustment of the elevation of the left end gate;
(c) a nut is attached to the ends of each of the left side guide bolts to limit the movement of the left end gate to substantially vertical movement;
(d) the right end gate includes a pair of right side guide slots that are engaged by the right side guide bolts to provide a measure of control for vertical adjustment of the elevation of the right end gate;
(e) a nut is attached to the ends of each of the right side guide bolts to limit the movement of the right end gate to substantially vertical movement.

4. The milling machine of claim 1 wherein the controller is:
(a) operatively attached to the rear linear actuator of the rear lifting column and is adapted to control the elevation of the rear lifting column with respect to the roadway surface;
(b) adapted to control the linear actuator in the rear lifting column by using the actual rear cut depth of the selected side of the machine to adjust the elevation of the rear lifting column to maintain the desired cut depth.

5. The milling machine of claim 4 :
(a) which includes a rear elevation sensor that is associated with the rear lifting column and is adapted to determine the rear elevation of the frame with respect to the roadway surface;
(b) wherein the controller is operatively attached to the rea

Assignees

• Roadtec Inc

Inventors

• Payne Byron
• Bevill James H
• Harrelson Raleigh

Classifications

• B60G99/00

  Subject matter not provided for in other groups of this subclass · CPC title

• B60G2300/09

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

• B60G3/01

  the wheel being mounted for sliding movement, e.g. in or on a vertical guide (camber maintaining means B60G3/26) · CPC title

• E01C23/127

  rotary, e.g. rotary hammers · CPC title

• B60G2300/32

  Track vehicles · CPC title