US20040006899A1

US20040006899A1 - Frame assembly for a work machine digging assembly

Info

Publication number: US20040006899A1
Application number: US10/190,699
Authority: US
Inventors: Roger Koch
Original assignee: Caterpillar Inc
Current assignee: Caterpillar Inc
Priority date: 2002-07-09
Filing date: 2002-07-09
Publication date: 2004-01-15

Abstract

A work machine having a frame structure and a digging assembly is disclosed. The work machine includes at least one pivot support supported on the frame structure and a first frame pivotally connected to the at least one pivot support for pivotal movement about a first axis. A second frame is disposed adjacent to the first frame. The second frame includes a top portion and a bottom portion connected by a closed side. The second frame is pivotally connected to the first frame for pivotal movement about a second axis oriented substantially perpendicular to the first axis. A swing frame is connected to the top and bottom portions of the second frame, and is configured to support the digging assembly.

Description

TECHNICAL FIELD

This invention relates generally to a frame system for adjusting the orientation of a swing frame of a work machine independent of the orientation of the work machine.

BACKGROUND

Excavating type machines, such as backhoe loaders, are versatile machines equipped with a work implement, such as a bucket mechanism, for grading slopes, digging trenches, and performing other excavations. In use, an operator must properly level the excavating type machine prior to beginning work or the machine will not dig with a clean horizontal surface. For instance, if the excavating type machine leans to one side, the bucket digs into the ground deeper at one corner of the bucket than the other. The ability to dig a vertical face or a ditch with a vertical wall is especially hindered by an out-of-level machine because the out-of-level machine can result in an out-of-level bucket that either digs a ditch with an angled face or creates jagged edges on the vertical face.

When an excavating type machine, such as a backhoe loader, is used to grade a slope, the backhoe loader is stationed in position at the top edge of the grade. The boom, stick, and bucket extend from the backhoe loader over the edge of the slope. An operator manipulates the bucket down onto the sloped ground to remove or distribute soil or earth along the slope. The boom and bucket are pivoted about a swing axis and extended to grade all accessible regions of the slope. During grading of the slope, the edge of the bucket maintains a proper roll position of being parallel to the plane of the graded slope only when the boom is pointing either directly down the slope or along the steepest gradient of the slope. If the boom pivots about the swing axis to any direction that is not directly down the slope or along the steepest gradient, the bucket edge is no longer parallel to the slope face. As such, when grading or moving soil, one edge of the bucket digs in before the other edge, causing ridges in the soil, instead of the desired flat surface.

Because the orientation of the swing axis is typically controlled by and dependent upon the orientation of the frame of the work machine, operators have attempted to tilt the work machine using stabilizing actuators and/or a front work implement to orient the work machine in a manner that provides a desired orientation of the swing axis relative to a working surface. By orienting the swing axis perpendicular to a desired work surface, for example, the bucket edge aligns with the desired work surface throughout the rotatable range of the digging assembly. Accordingly, by orienting the swing axis perpendicular to a desired work surface, an operator may create a smooth, ridge free surface throughout the pivot range of the digging assembly when digging or grading because the bucket edge is constantly aligned parallel to the desired surface. However, adjusting the work machine so that the swing axis is perpendicular to a desired slope is not always easy, and if the desired slope is steep, there may be safety concerns. Furthermore, sitting in a leaning or tipped chair all day is strenuous and tiring for an operator.

One attempt to address the situation described above is found in U.S. Pat. No. 3,977,547 to Holopainen (the '547 patent). The '547 patent discloses a material handling apparatus having a junction element that includes a first roll arm for adjustments in the roll mode of motion, a second roll arm disposed upon the first roll arm for motion in a pitch mode of motion, and a third roll arm disposed on the second roll arm for rotation and attachment to an accessory tool. However, this system has several deficiencies, including that it offers a very limited degree of motion, it may only be used on a machine specifically designed for it, and accommodates only those work implements specifically designed to be used with it.

Known devices for orienting a work implement have a number of deficiencies and/or limitations. For example, known devices may not be capable of aligning a swing axis perpendicular to a steep slope because of the limited degrees of motion offered by the linear actuators. Such known devices also are not capable of being retrofitted to existing machines, but instead are designed to attach only to a vehicle specifically designed for such a device. Moreover, known devices may require an extra long stick to extend beyond the vehicles on which they are placed. This extra long stick creates increased cantilever weight, requiring additional reinforcement and extra heavy duty actuators. Finally, known devices may not allow an operator to have a good view of the hole being dug because the operator has difficulty seeing over the extended end of the machine.

The present invention is directed to overcoming one or more of the problems or disadvantages associated with the prior art.

SUMMARY OF THE INVENTION

In one aspect of the invention, a work machine having a frame structure and a digging assembly is disclosed. The work machine includes at least one pivot support supported on the frame structure and a first frame pivotally connected to the at least one pivot support for pivotal movement about a first axis. A second frame is disposed adjacent to the first frame. The second frame includes a top portion and a bottom portion connected by a closed side. The second frame is pivotally connected to the first frame for pivotal movement about a second axis oriented substantially perpendicular to the first axis. A swing frame is connected to the top and bottom portions of the second frame, and is configured to support the digging assembly.

In another aspect of the invention, a method for controlling a digging assembly on a work machine having a frame structure is disclosed. The method includes pivoting a first frame about a first axis to orient the first frame to a desired position. The first frame is connected by at least one pivot support to the frame structure of the work machine. The method also includes pivoting a second frame about a second axis to orient the second frame to a desired position. The second axis is substantially perpendicular to the first axis, and the second frame is disposed adjacent the first frame. The second frame includes a top portion and a bottom portion connected by a closed side, and is pivotally connected to the first frame. The method also includes pivoting a swing frame connected to the top and bottom portions of the second frame to rotate the digging assembly through a range of motion.

In another aspect of the invention, a frame assembly for orienting a work machine digging assembly is disclosed. The work machine includes a frame structure and at least one pivot support supported on the frame structure. The frame assembly includes a first frame configured to pivot about a first axis, at least one first pin configured to connect the first frame to the at least one pivot support, and a second frame configured to pivot about a second axis. The second axis is oriented substantially perpendicular to the first axis. The second frame includes a top portion and a bottom portion connected by a closed side. The frame assembly also includes at least one second pin configured to connect the second frame to the first frame.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features and advantages of the invention will be apparent from the following, more particular description of the invention, as illustrated in the accompanying drawings. [0012]
FIG. 1 is a diagrammatic side view of one exemplary work machine according to the invention. [0013]
FIG. 2 is an enlarged side view of a portion of the work machine shown in dotted lines in FIG. 1. [0014]
FIG. 3 is a front view of the frame assembly of FIG. 2. [0015]
FIG. 4 is a top view of the frame assembly of FIG. 2.[0016]

DETAILED DESCRIPTION

Embodiments of the present invention are now described with reference to the figures where like reference numbers indicate identical or functionally similar elements. Also in the figures, the left most digit of each reference number corresponds to the figure in which the reference number is first used. While specific configurations and arrangements are discussed, it should be understood that this is done for illustrative purposes only. A person skilled in the art will recognize that other configurations and arrangements can be used without departing from the spirit and scope of the invention. [0017]
With reference to FIG. 1, a [0018] work machine 100 for performing a variety of work functions includes a frame structure 102, an operator's compartment 104 which is supported on the frame structure 102, and a digging assembly 106, which is supported by the frame structure 102 and is typically connected to the rear of the work machine 100.
[0019] Work machine 100 further includes front wheels 108 and rear wheels 110 for supporting work machine 100. Work machine 100 could be of a type commonly referred to as a backhoe loader and may further include a front work implement assembly 112, such as a loader bucket assembly, which may be connected to the frame structure 102 at the front of the work machine 100. While the exemplary embodiment is shown as a backhoe loader, other types of work machines may utilize the present invention.
The digging [0020] assembly 106 includes a swing frame 114, a boom member 116, a stick member 118, and a work implement 120. Digging assembly 106 can be used, for example, to dig a hole or ditch, level the ground, or grade an area at a desired angle, and may be disposed at the rear of work machine 100. Boom member 116 extends between swing frame 114 and stick member 118, and stick member 118 extends from boom member 116 to work implement 120. Work implement 120 may be, for example, a bucket or shovel for picking up and moving soil or other materials, but may be any other implement as would be apparent to one skilled in the relevant art. Accordingly, use of the term digging assembly is not limited only to structures that dig, may be any of a variety of working apparatuses. Digging assembly 106 may operate using actuators configured as is known in the art.
[0021] Work machine 100 may include a stabilizing system 121 including stabilizing arms extending from frame structure 102 that are adapted to stabilize work machine 100 during operation. Front work implement assembly 112 may be used in conjunction with stabilizing system 121 to stabilize work machine 100 in a tripod-like three-point manner.
A multi-degree-of [0022] freedom frame assembly 124, which is shown circled in dashed lines in FIG. 1, may be disposed at the rear of work machine 100 between frame structure 102 and digging assembly 106. Frame assembly 124 allows a swing axis 122 of swing frame 114 to have rotational ability in both the pitch direction and the roll direction of the work machine. The roll direction is from one side of work machine 100 to the other side, and the pitch direction is the direction from front to back and back to front of work machine 100. Frame assembly 124 allows an operator to orient swing axis 122 in a desired direction independent of the orientation of the frame structure 102 of the work machine. This orientation of the swing axis may be accomplished by an automated controls system, by manual operator commands, or by some combination of the automated and manual control.
FIGS. [0023] 2-4 show the frame assembly 124 of FIG. 1 in greater detail. As depicted in the figures, frame assembly 124 includes a roll frame 206 for moving swing axis 122 in a roll direction and a pitch frame 208 for moving swing axis 122 in a pitch direction. Swing frame 114 pivots about swing axis 122. Roll frame 206 is rotatably connected to pitch frame 208. Pitch frame 208 is supported by or connected to a fixed structure, such as for example, frame structure 102. Frame structure 102 of the exemplary embodiment is the frame structure of a work machine. The fixed structure could also be a member such as a bar or platform welded or otherwise attached to frame structure 102, as would be apparent to one skilled in the relevant art. As used herein, references to the frame structure of the work machine are intended to include members such as a bar or platform connected to the rear of the work machine frame.
[0024] Swing frame 114 may include a top swing arm 212 and a bottom swing arm 214 extending from a main body 216. Top and bottom swing arms 212, 214 each may include holes, which are aligned and formed to fit a top and a bottom swing pin 218, 219, respectively, defining the swing axis 122 about which swing frame 114 may rotate.
[0025] Roll frame 206 may be a generally C-shaped frame structure having a top portion 220, a bottom portion 222, a closed side 224, and an open side 226. Open side 226 is configured to receive top and bottom swing arms 212, 214 of swing frame 114. Roll frame 206 includes openings for receiving and securing swing pins 218, 219. Accordingly, swing frame 114 may rotate about swing axis 122 when connected to roll frame 206. Roll frame 206 may include a connection bar support 228 for securing top swing arm 212 into roll frame 206. Connection bar support 228 may be a right-angled support that extends from top portion 220 toward open side 226. Top swing arm 212 of swing frame 114 may fit between top portion 220 and connection bar support 228. Top swing pin 218 may extend from top portion 220, through top swing arm 212, and into connection bar support 228 of roll frame 206, securely attaching top swing arm 212 of swing frame 114 to top portion 220 of roll frame 206, thereby supporting the digging assembly of the work machine. Connection bar support 228 need not be angled, but could extend from closed side 224 or be otherwise configured to provide support.
[0026] Bottom portion 222 of roll frame 206 may include an opening for receiving bottom swing pin 219, thereby aligning the opening in bottom portion 222 with the through hole in the bottom swing arm 212, securely attaching bottom swing arm 212 of swing frame 114 to bottom portion 222 of roll frame 206.
[0027] Actuators 230 extend from closed side 224 of roll frame 206 to swing frame 114. Actuators 230 control the rotation of swing frame 114 about swing axis 122. In this exemplary embodiment, two actuators are used to control the rotation of swing frame 114 about swing axis 122. However, more or less than two actuators could be used, as would be apparent to one skilled in the relevant art.
[0028] Roll frame 206 may be connected to pitch frame 208 through a connecting structure, such as for example, roll pins 232. Roll pins 232 form a roll axis 234, about which roll frame 206 may rotate. The connecting structure could be any structure that connects the roll frame to the pitch frame and that allows roll frame 206 to rotate about roll axis 234.
[0029] Pitch frame 208 may be a three-sided structure that is open at the top, as oriented in FIG. 2. Bottom portion 222 of roll frame 206 fits within the open top of pitch frame 208, as seen in FIG. 2. Pitch frame 208 may include a bottom section 236, a first wall 238 disposed on the side adjacent to swing frame 114, and a second wall 240 adjacent to closed side 224 of roll frame 206. First wall 238 and second wall 240 cooperate with roll pins 232 to rotatably support roll frame 206.
[0030] Pitch frame 208 may be connected to frame structure 102 by a connecting structure, such as, for example, pitch pins 242. Pitch pins 242 form a pitch axis 346 about which pitch frame 208 may rotate. Pitch axis 346 may be arranged to be substantially perpendicular to roll axis 234. Pitch pins 242 may connect to pivot supports 244, which in this embodiment, constitute substantially triangular shaped elements having an opening configured to receive and hold pitch pins 242. Pivot supports 244, however, could be any structure that connects pitch frame 208 to frame structure 102, and that allows pitch frame 208 to rotate about pitch axis 346. Pivot supports 244 may be disposed adjacent the end of frame structure 102, thereby allowing pitch frame 208 to have a full range of motion, not limited by the frame structure. Accordingly, pitch frame 208 may extend beyond a rearward end of the frame structure 102. Pivot supports 244 may be integrally formed as part of frame structure 102 or connected indirectly to frame structure 102 through a member supported by the frame structure.
[0031] Bottom section 236 of pitch frame 208 may include an extension 348 that extends beyond the width of roll frame 206 (best seen in FIG. 4). Extension 348 is connected at one end of, and used to support a roll actuator 250. Extension 348 may be integrally formed with bottom section 236, or may be formed separately, and connected or otherwise attached to bottom section 236 of pitch frame 208. Roll actuator 250 extends from closed side 224 of roll frame 206 to extension 348 of pitch frame 208, in a direction perpendicular to, but not crossing, roll axis 234. Roll actuator 250 controls the rotation of roll frame 206 about roll axis 234. Accordingly, to orient swing axis 122 in a roll direction, roll actuator 250 is activated to rotate roll frame 206 about roll axis 234, thereby rotating swing axis 122 in the roll direction.
Likewise, a [0032] pitch actuator 252 may control the rotation of pitch frame 208 about pitch axis 346. Pitch actuator 252 may extend from second wall 240 of pitch frame 208 to frame structure 102 in a direction perpendicular to, but not crossing, pitch axis 346. Accordingly, to rotate swing axis 122 in a pitch direction, pitch actuator 252 may be activated to rotate pitch frame 208 about pitch axis 346, thereby rotating roll frame 206, swing frame 114 and swing axis 122 in the pitch direction.
Various alternatives to the exemplary structure of [0033] frame assembly 124 are contemplated. For example, in one exemplary embodiment, the swing frame may be directly connected to the pitch frame and the roll frame may be directly connected to the frame structure.

INDUSTRIAL APPLICABILITY

To properly grade the face of a slope throughout the rotatable range of a digging assembly of a work machine, such as a backhoe loader, an operator must properly align the bucket of the machine so that the bucket edge is aligned parallel to the desired slope. Failure to properly align the bucket edge results in saw tooth ridges in the soil, as one end of the bucket edge digs deeper into the soil than the other end. To align the bucket with the slope, an operator typically adjusts the position of the work machine using the stabilizing bars until a swing axis is perpendicular to the desired slope. However, to sit in a work machine that is tilted is cumbersome and tiring. Furthermore, if the desired slope is steep, adjusting the work machine so that the swing axis is perpendicular to the slope may create safety issues. [0034]
The present invention is a frame assembly giving selective movement and rotational ability to the digging assembly of the work machine so that an operator may set the swing axis to a desired orientation (e.g. perpendicular to a desired slope) without having to adjust the position of the work machine. Accordingly, an operator is able to easily orient the swing axis so that the operator may dig without creating uneven walls in a ditch or saw-tooth ridges on a graded slope, even for steep slopes. [0035]
The frame assembly increases operator efficiency because the operator may now keep the operator cab at a comfortable angle, allowing an operator to work for longer periods with less fatigue, thereby requiring fewer breaks. [0036]
The present invention is adaptable to a variety of work machines where maintaining a swing axis perpendicular to a work surface may be desirable. For instance, the present invention may be useful on excavators, front shovels, material handlers, or any work machine having a swing axis. The frame assembly is configured so that it may be retrofitted to existing machines using existing digging systems. One method of doing so is to configure the roll frame of the frame assembly to receive and fit a standard swing frame currently being manufactured or used on work machines. [0037]
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims. [0038]

Claims

What is claimed is:

1. A work machine having a frame structure and a digging assembly, the work machine comprising:

at least one pivot support supported on the frame structure;

a first frame pivotally connected to the at least one pivot support for pivotal movement about a first axis;

a second frame disposed adjacent the first frame, the second frame having a top portion and a bottom portion connected by a closed side, the second frame being pivotally connected to the first frame for pivotal movement about a second axis oriented substantially perpendicular to the first axis; and

a swing frame connected to the top and bottom portions of the second frame, the swing frame being configured to support the digging assembly.

2. The work machine of claim 1, wherein the first frame is a pitch frame pivotal in a pitch direction and the second frame is a roll frame pivotal in a roll direction.

3. The work machine of claim 2, further including a connection bar support configured to secure the swing frame to the roll frame.

4. The work machine of claim 2, further including:

roll pins connecting the roll frame to the pitch frame; and

pitch pins connecting the pitch frame to the at least one pivot support.

5. The work machine of claim 2, further including:

a swing actuator extending from the roll frame to the swing frame to rotate the swing frame about a swing axis;

a pitch actuator extending from the pitch frame to the frame structure; and

a roll actuator extending from the pitch frame to the roll frame.

6. The work machine of claim 5, wherein the pitch frame includes a bottom section and an extension extending therefrom.

7. The work machine of claim 1, wherein the first frame extends rearwardly of a rearward end of the machine frame structure.

8. The work machine of claim 1, wherein the pivot supports are integral with the frame structure.

9. The work machine of claim 1, wherein the pivot supports are connected indirectly to the frame structure through a member supported by the frame structure.

10. The work machine of claim 1, wherein a swing axis is defined by at least one swing pin connecting the swing frame with the second frame.

11. A method for controlling a digging assembly on a work machine having a frame structure, the method comprising:

pivoting a first frame about a first axis to orient the first frame to a desired position, the first frame being connected by at least one pivot support to the frame structure of the work machine;

pivoting a second frame about a second axis to orient the second frame to a desired position, the second axis being substantially perpendicular to the first axis, the second frame being disposed adjacent the first frame and having a top portion and a bottom portion connected by a closed side, the second frame being pivotally connected to the first frame; and

pivoting a swing frame connected to the top and bottom portions of the second frame to rotate the digging assembly through a range of motion.

12. The method of claim 11, further including:

activating a swing actuator to pivot the swing frame about a swing axis.

13. The method of claim 12, wherein the first and second frames are pivoted to their respective desired positions to thereby orient the swing axis in a direction substantially perpendicular to a desired work surface for the digging assembly.

14. The method of claim 12, wherein pivoting the first frame includes pivoting the first frame in a pitch direction, the first frame being a pitch frame, and

wherein pivoting the second frame includes pivoting the second frame in a roll direction, the second frame being a roll frame.

15. The method of claim 14, including:

activating a swing actuator to pivot the swing frame, the swing actuator extending from the roll frame to the swing frame;

activating a pitch actuator to pivot the pitch frame in the pitch direction, the pitch actuator extending from the pitch frame to the frame structure; and

activating a roll actuator to pivot the roll frame in the roll direction, the roll actuator extending from the roll frame to the pitch frame.

16. A work machine comprising:

a frame structure;

pivot supports supported on the frame structure;

a pitch frame having a bottom section extending between a first wall and a second wall;

pitch pins connecting the bottom section of the pitch frame with the pivot supports, the pitch pins forming a pitch axis;

a C-shaped roll frame situated at least partially between the first and second walls of the pitch frame, the roll frame having a top portion and a bottom portion connected by a closed side, the closed side being adjacent to the second wall of the pitch frame;

roll pins connecting the bottom portion of the roll frame with the first and second walls of the pitch frame, the roll pins forming a roll axis oriented substantially perpendicular to the pitch axis;

a swing frame having top and bottom swing arms extending between the top and bottom portions of the roll frame; and

at least one swing pin extending from the top and bottom swing arms to the top and bottom portions of the roll frame.

17. The work machine of claim 16, further including:

a work implement;

a stick member connected to the work implement; and

a boom member connected to the stick member and the swing frame such that the work implement may be oriented by selective movement of the pitch frame and roll frame.

18. The work machine of claim 16, wherein the pitch frame extends rearwardly of a rearward end of the frame structure.

19. The work machine of claim 16, wherein the pitch frame includes a bottom section and an extension extending therefrom.

20. The work machine of claim 16, wherein the pivot supports are integral with the frame structure.

21. The work machine of claim 16, wherein the pivot supports are connected indirectly to the frame structure through a member supported by the frame structure.

22. A frame assembly for orienting a work machine digging assembly, the work machine having a frame structure and at least one pivot support supported on the frame structure, the frame assembly comprising:

a first frame configured to pivot about a first axis;

at least one first pin configured to connect the first frame to the at least one pivot support;

a second frame configured to pivot about a second axis, the second axis being oriented substantially perpendicular to the first axis, the second frame having a top portion and a bottom portion connected by a closed side; and

at least one second pin configured to connect the second frame to the first frame.

23. The frame assembly of claim 22, wherein the first frame includes a bottom section extending between first and second walls, the at least one second pin being configured to connect the first and second walls to the second frame.

24. The frame assembly of claim 22, further including a connection bar support configured to secure a swing frame to the second frame.

25. The frame assembly of claim 22, further including an actuator extending from the first frame to the second frame.

26. The frame assembly of claim 25, wherein the first frame includes a bottom section and an extension extending therefrom.