Patent Application
20230102419
The present disclosure relates to a work machine such as a compact track loader, and a method of optimizing precision grade control during a grading operation.
Work machines with precision grade control encounter varying soil conditions and types during operation. The variability may arise from shifts in weather patterns from day-to-day operations at a worksite or grading in urban areas where surrounding materials may contribute to soil conditions. Furthermore, the work machine may encounter dynamically changing load conditions on the ground-engaging attachment coupled to the work machine because of this variability. Because of the complexity of the systems pose, therein lies an opportunity to improve work machine operation during grading.
This summary is provided to introduce a selection of concepts that are further described below in the detailed description and accompanying drawings. This summary is not intended to identify key or essential features of the appended claims, nor is it intended to be used as an aid in determining the scope of the appended claims.
The present disclosure relates to an apparatus and method for optimizing a precision grading operation by a work machine.
According to an aspect of the present disclosure, a work machine may include a frame, a ground-engaging attachment, an attachment coupler coupling the ground-engaging attachment to the frame, an actuator, an adjustable linkage, a sensor, and a controller. The adjustable linkage adjusts a position of the ground-engaging attachment relative to the frame. The adjustable linkage comprises of a first portion and a second portion. An enclosure encircles the second portion and creates an annular chamber between the enclosure and the second portion. A sensor is coupled to the annular chamber wherein the sensor measures a pressure in the annular chamber and creates a signal based on the pressure. A controller is configured to monitor the sensor signal and perform one or more actions based on the sensor signal. The second portion of the adjustable linkage may be floating within the enclosure.
The pressure is indicative of a load on the ground-engaging attachment.
The annular chamber may be partitioned into a first annular chamber and a second annular chamber. The sensor measures a first pressure in the first annular chamber and a second pressure in the second annular chamber wherein the sensor signal is based on the pressure differential between the first pressure and the second pressure.
The annular chamber may be filled with an incompressible fluid.
The second portion of the adjustable linkage may be floating within the enclosure.
The work machine may further comprise of a ball joint coupling the ground engaging-attachment to the work machine and a lower portion of the ground-engaging attachment. The ball joint may enable the ground-engaging attachment to pivot about a point, wherein pivoting the ground-engaging attachment about the ball joint creates a proportionate force on the pitch link
Actuation of the actuator may move the ground-engaging attachment in a direction of pitch, roll, or jaw.
The actions may comprise of determining a target grade and sending a command to move the ground-engaging attachment toward the target grade.
The actions may comprise of modifying one or more of an engine speed, a transmission torque, a brake pressure, and a travel speed.
The annular chamber may further comprise of an end chamber, the end chamber formed between an end wall of the second portion and a base of the enclosure.
In an alternative embodiment, the sensor may measure a stress on the annular chamber and create a sensor signal based on the stress. The sensor may be located between an end wall of the second portion and a base of the enclosure, or the end chamber.
A method of operating a work machine with a ground-engaging attachment may comprise of sensing hydraulic pressure differential by a sensor between a first annular chamber and a second annular chamber of a pitch link wherein the pitch link coupled to the work machine on a first end, and coupled to the ground-engaging attachment on a second. In a next step, the method includes sending a sensor signal based on the pressure differential wherein the sensor signal is indicative of a load on the ground-engaging attachment. The controller may then determine if the sensor is within an optimal range and perform one or more action based on the sensor signal.
The sensor may measure a hydraulic pressure differential between a first annular chamber and a second annular chamber of the pitch link.
The pitch link may be coupled to a top portion of the ground-engaging attachment wherein the ground-engaging attachment has a cutting edge on a bottom portion of the ground-engaging attachment. A ball joint may couple the ground engaging-attachment to the work machine and a lower portion of the ground-engaging attachment than the pitch link, the ball joint enabling the ground-engaging attachment to pivot about a point, wherein pivoting the ground-engaging attachment about the ball joint creates a proportionate force on the pitch link
Other features
Other features
Other features and aspects of the disclosure will become apparent by consideration of the following 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 supporting other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.
As used herein, unless otherwise limited or modified, lists with elements that are separated by conjunctive terms (e.g., “and”) and that are also preceded by the phrase “one or more of” or “at least one of” indicate configurations or arrangements that potentially include individual elements of the list, or any combination thereof. For example, “at least one of A, B, and C” or “one or more of A, B, and C” indicates the possibilities of only A, only B, only C, or any combination of two or more of A, B, and C (e.g., A and B; B and C; A and C; or A, B, and C).
As used herein, the term “controller” is a computing device including a processor and a memory. The “controller” may be a single device or alternatively multiple devices. The controller may further refer to any hardware, software, firmware, electronic control component, processing logic, processing device, individually or in any combination, including without limitation: application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and memory that executes one or more software or firmware programs, a combinational logic circuit, and/or other suitable components that provide the described functionality.
The term “processor” is described and shown as a single processor. However, two or more processors can be used according to particular needs, desires, or particular implementations of the controller and the described functionality. The processor may be a component of the controller, a portion of the object detector, or alternatively a part of another device. Generally, the processor can execute instructions and can manipulate data to perform the operations of the controller, including operations using algorithms, methods, functions, processes, flows, and procedures as described in the present disclosure.
The work machine 100 comprises a boom assembly 120 coupled to the frame 105. A ground-engaging attachment 125, or work tool, may be pivotally coupled at a forward portion 130 of the boom assembly 120, while a rear portion 140 of the boom assembly 125 is pivotally coupled to the frame 105. The ground-engaging attachment 125 is illustrated as a blade but may be any number of work tools such as dozer blades, box blades, soil conditioners, just to name a few possibilities. The ground-engaging attachment 125 may be coupled to the boom assembly 120 through an attachment coupler 145 such as Deere and Company's Quik-Tatch, which is an industry standard configuration and a coupler universally applicable to many Deere attachments and several after-market attachments. The attachment coupler 145 may be coupled to a forward portion 130 of the boom arms 150, or more specifically a portion of the boom arms in the fore portion of the boom assembly 120.
The boom assembly 120 is moveable relative to the frame 105 by a pair of first hydraulic cylinders 160, wherein the pair of first hydraulic cylinders 160 may also conventionally be referred to as a pair of lift cylinders (one coupled to each boom arm) for a compact track loader for movement in the direction of lift 162. The attachment coupler 145 is moveable relative to the frame 110 by a pair of second hydraulic cylinders 165, conventionally referred to as tilt cylinders, for movement in the direction of pitch 180. The movement of the ground-engaging attachment 110 (shown here as a blade) relative to the frame 105 may be referred to as roll 170 or the roll direction, pitch 180 or the pitch direction, and yaw 190 or the yaw direction.
Now referring to
Now also referring to
In one embodiment, the second portion 230 comprises an intermediate hollow cylinder 275 and couples to the length adjusting nut member 265 through a threaded inner surface. As the length adjusting nut member 265 is rotated, the shaft 226 slides into or out of the intermediate hollow cylinder 275 along the shaft axis 229. The intermediate hollow cylinder 275 is encircled by an enclosure 240 forming an annular chamber (245a, 245b) therebetween. The enclosure 240 has a collar 285 to position the enclosure 240 around the external surface of the intermediate hollow cylinder 275. A closing cap 290 secures the enclosure 240 in place thereby sealing the annular chamber 245. This collar 285 is formed of a radial wall and an axial wall. The closing cap 290 closes the enclosure 240 and seals an annular gap 245 with the radial wall.
As the intermediate hollow cylinder 275 is coupled to the nut member 265, a flange 268 on the nut member 265 allows movement about shaft axis 229 while limiting linear motion of the intermediate hollow cylinder 275 relative to the enclosure 240, and thereby limiting a change in volume of the annular chamber 245 as the flange 268 abuts the collar 285.
The enclosure 240 has a base 295 rigidly coupled to the link head end 297. The link head end 297 couples the adjustable linkage 200 with the attachment coupler 145. In an alternative embodiment (not shown), the head end 297 may be coupled with the ground-engaging attachment 125 at the first pivotal coupling 215, and the shaft 226 may be coupled to the attachment coupler 145.
The annular chamber 245 may be divided into a first annular chamber 245a, a second annular chamber 245b and an end chamber 246 by means of seals 320a, 320b and 320c. The seals 320a and 320b may be an integrated component of the intermediate hollow cylinder 275 and the seal 320c may be integral to the enclosure. The first annular chamber 245a is formed between the seals 320a and 320b, the second annular chamber 245b is formed between the seals 320b and 320c. Seal 320c separates the second annular chamber 245b from end chamber 246. In a preferred embodiment, the first annular chamber 245a and the second annular chamber 245b are filled with an incompressible fluid 298. Ports 257 enable a refilling of fluid 298 for maintenance, if needed. An exemplary fluid is a standard hydraulic oil used in construction machinery such as skid steer machines. The end chamber 246 is formed between the end wall of the intermediate hollow cylinder and the base of the enclosure 240. In a first embodiment, the end chamber is empty and serves to collect any leakage of the fluid through the seals. A drain plug 300 at the base 295 of the enclosure 240 allows periodic cleaning of the incompressible fluid within annular chambers 245.
A sensor 250 is coupled to the enclosure 240 to measure the fluidic pressure within the enclosure 240. The sensor 250 may be configured to generate a sensor signal 255 based on the fluid pressure within the annular chamber 245. By way of a non-limiting example, a first sensor 250a and a second sensor 250b are provided to measure the fluid pressure within the first annular chamber 245a and the second annular chamber 245b, respectively. The first sensor 250a generates a first sensor signal 255a based on the fluid pressure in the first annular chamber 245a. The second sensor 250b generates a second sensor signal 255b based on the fluid pressure in the second annular chamber 245b. The sensor signal 255 may be based on the pressure differential between the first pressure and the second pressure. The pressure of each of the annular chambers (245a, 245b) may change during operation of the work machine 100 wherein the load imposed on the blade can be derived from the pressure measured by sensors (250a, 250b). In an alternative embodiment the pressure differential over a period of time may be gauges from the change in pressure in a single annular chamber 250.
In an alternative embodiment, the sensor may include a third sensor 245c to measure a pressure in the end chamber 246 as well if filled with incompressible fluid 298. Several combinations of pressure differentials can exist. These may include 245a and 245c, 245b and 245c, and 245a, 245b, and 245c. Alternatively, measuring a single pressure from a single chamber may also be used as an indication of fluctuations in loads encountered by the blade 125.
As shown in
The adjustable linkage 200 described so far advantageously carries dual functions of adjusting the position of the blade 125 with respect to the attachment coupler 145 while measuring the pressure indicative of the load 210 on the blade 125.
The first portion of the adjustable linkage 200 namely the shaft 226, length adjusting nut member 265, the intermediate hollow cylinder 275 and the seal B act like a rigid member in the axial direction 229, the pulling force on the adjustable linkage 200 increase the pressure in the first annular chamber 245a and the pressure in the second annular chamber 245b changes accordingly.
