Ripper depth limit based upon grade control depth

A control system for automatically controlling a ripper of a work vehicle based on a desired grade control depth. The control system comprises at least one feedback device providing a feedback signal indicative of an actual grade control depth. A controller is in communication with the at least one feedback device and configured to raise the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.

FIELD OF THE DISCLOSURE

The present disclosure generally relates to work vehicles, and more particularly to a system and method for automatically controlling a ripper of a work vehicle based on a desired grade control depth.

BACKGROUND OF THE DISCLOSURE

In order to break up soil and then move soil with a blade to achieve a desired grade, a ripper is commonly used. The ripper is commonly adjusted independently of a blade depth until the desired grade is achieved.

SUMMARY OF THE DISCLOSURE

In one embodiment, a control system for automatically controlling a ripper of a work vehicle based on a desired grade control depth is disclosed. The control system comprises at least one feedback device providing a feedback signal indicative of an actual grade control depth. A controller is in communication with the at least one feedback device and is configured to raise the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.

In another embodiment, a work vehicle is disclosed. The work vehicle comprises a ripper and a control system. The control system automatically controls the ripper based on a desired grade control depth. The control system comprises at least one feedback device providing a feedback signal indicative of an actual grade control depth and a controller in communication with the at least one feedback device and configured to raise the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.

In yet another embodiment, a method for automatically controlling a ripper of a work vehicle based on a desired grade control depth is disclosed. The method comprises providing a feedback signal indicative of an actual grade control depth. The method also comprises raising the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.

Other features and aspects will become apparent by consideration of the detailed description and accompanying drawings.

Before any embodiments are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Further embodiments of the invention may include any combination of features from one or more dependent claims, and such features may be incorporated, collectively or separately, into any independent claim.

DETAILED DESCRIPTION

FIGS. 1 and 2illustrate a work vehicle10having a blade15, an operator station20having an operator interface25, a ripper30, and an engine35. The work vehicle10may be any work vehicle to which a ripper may be coupled, such as a crawler or a motor grader, to name a few examples. The work vehicle10may be controlled by an operator located in the operator station20. The operator may command the work vehicle10to move forward, move backward, and turn. In the case of the work vehicle10, those commands are sent to hydraulic pumps, driven by the engine35, which direct pressurized hydraulic fluid to hydraulic motors that turn tracks or wheels. The engine35may be a diesel engine. Alternatively, the tracks or wheels may be turned by electric motors.

The blade15is positioned at a front of the work vehicle10and may be attached to the work vehicle10in a number of different manners. In this embodiment, the blade15is attached to the work vehicle10through a linkage which includes a series of pinned joints, structural members, and hydraulic cylinders. This configuration allows the blade15to be moved up and down relative to the ground, rotate around a vertical axis (i.e., an axis normal to the ground), rotate around a longitudinal axis (e.g., a fore-aft axis of the work vehicle10), and rotate around a lateral axis of the work vehicle10(i.e., a left-right axis of the work vehicle10). These degrees of freedom permit the blade15to engage the ground at multiple depths and cutting angles. Alternative embodiments may involve blades with greater degrees of freedom, such as those found on some motor graders, and those with fewer degrees of freedom, such as “pushbeam” style blades found on some crawlers and blades which may only be raised, lowered, and rotated around a vertical axis as found on some excavators and skidders.

The operator may command movement of the blade15from the operator station20. In the case of the work vehicle10, those commands are sent, including mechanically, hydraulically, and/or electrically, to a hydraulic control valve. The hydraulic control valve receives pressurized hydraulic fluid from a hydraulic pump, and selectively sends such pressurized hydraulic fluid to a system of hydraulic cylinders based on the operator's commands. The hydraulic cylinders, which in this case are double-acting, in the system are extended or retracted by the pressurized fluid and thereby actuate the blade15.

The ripper30is positioned at a rear of the work vehicle10and may be attached to the work vehicle10in a number of different manners. In this embodiment, the ripper30is attached to the work vehicle10through a linkage which includes a series of pinned joints, structural members, and hydraulic cylinders. This configuration allows the ripper30to be moved up and down relative to the ground.

With reference toFIG. 1, the illustrated work vehicle10is a crawler40for moving material. The crawler40includes a left track45and a right track50. As used herein, “left” and “right” refer to the left and right sides of the operator when the operator is sitting within the operator station20and facing the blade15. The ripper30is coupled to a rear of the crawler40.

Referring toFIG. 2, the illustrated work vehicle10is a motor grader55for spreading and leveling dirt, gravel, or other materials. The motor grader55includes a plurality of left wheels60(right wheels not shown). The ripper30is coupled to a rear of the motor grader55.

With reference toFIG. 3, the work vehicle10has a control system65. The control system65automatically controls the ripper30of the work vehicle10based on a desired grade control depth70. The operator may input the desired grade control depth70into the operator interface25. The operator may also input a ripper depth limit75into the operator interface25.

At least one feedback device80is provided. The feedback device80provides a feedback signal indicative of an actual grade control depth85. The feedback device80may be a blade position sensor90coupled to the blade15for providing the feedback signal indicative of the actual grade control depth85.

A controller95is in communication with the at least one feedback device80and the hydraulic cylinders to raise and lower the blade15as well as the hydraulic cylinders to raise and lower the ripper30. The controller95is configured to raise the ripper30when the feedback signal indicates the actual grade control depth85is equal to the desired grade control depth70. Alternatively, the controller95may be configured to raise the ripper30when the feedback signal indicates that the actual grade control depth85is approaching the desired grade control depth70or within some predetermined range such as plus or minus 1 inch. The controller95may also not allow the ripper30to lower below the ripper depth limit75. Alternatively, the controller95may not allow the ripper30to approach a specified distance or range of the ripper depth limit75, such as 1 inch or 1-6 inches.

Referring toFIG. 4, in another embodiment a grade control controller100is configured to control the blade15by communicating with the hydraulic cylinders for raising, lowering, and moving the blade15. The at least one feedback device80is the blade position sensor90providing the feedback signal indicative of the actual grade control depth85to the grade control controller100.

The controller95may be a ripper controller105that receives the feedback signal from the grade control controller100and is in communication with the hydraulic cylinders for raising and lowering the ripper30. The ripper controller105is configured to raise the ripper30when the feedback signal indicates the actual grade control depth85is equal to the desired grade control depth70. Alternatively, the ripper controller105may be configured to raise the ripper30when the feedback signal indicates that the actual grade control depth85is approaching the desired grade control depth70or within some predetermined range such as plus or minus 1 inch.

A speed sensor110may be provided. The speed sensor110may provide a speed feedback signal indicative of work vehicle speed115to the controller95(FIG. 3) or the grade control controller100.

A track slip sensor120may be provided. The track slip sensor120may provide a track slip feedback signal indicative of track slip125relative to ground. The track slip sensor120is in communication with at least one of the controller95(FIG. 3), the grade control controller100, and the ripper controller105.

The grade control controller100is configured to lower the speed of the work vehicle10and/or raise the blade15when the track slip feedback signal indicates track slip125is occurring. The ripper controller105is configured to raise the ripper30when the track slip feedback signal indicates track slip125is occurring.

A ripper load feedback device130may be provided. The ripper load feedback device130may provide a ripper load feedback signal indicative of a ripper load135. The ripper controller105receives the ripper load feedback signal and is configured to raise the ripper30when the ripper load feedback signal indicates the ripper load135has exceeded a threshold ripper load140. Alternatively, the ripper controller105may raise the ripper30when the ripper load feedback signal indicates the ripper load135is approaching the threshold ripper load140or within some predetermined range of the threshold ripper load140such as 1 inch or 1-6 inches.

A method for automatically controlling a ripper30of a work vehicle10based on a desired grade control depth70is illustrated inFIG. 5. In Step145, the feedback signal indicative of the actual grade control depth85is provided. In Step150, the operator interface25where the operator can input the desired grade control depth70is provided. In Step155, the ripper30is raised when the feedback signal indicates the actual grade control depth85is equal to the desired grade control depth70.

Various features are set forth in the following claims.