Patent Application
20080110650
The present disclosure relates generally to machines and machine hydraulic systems having movable hydraulically actuated devices, and relates more particularly to a machine and method wherein components of a hydraulic circuit for providing hydraulic power to a device are supported by a pivoting rigid support segment of the hydraulic circuit during sideshift movement of a coupler to which the device is mounted.
Construction machines, in particular earthworking machines, are indispensable to modern society. Agriculture, mining, building and road construction and a host of other endeavors rely upon the transport, placement and treatment of soil, rock and other materials with construction machines. While a great many successful and important machines and machine configurations have been developed over the years, specialization of certain classes of machines has lead to their use primarily within relatively narrow, albeit important, applications. Motor graders and the like are one example of a class of machines well-suited to certain tasks, but heretofore somewhat limited in their ability to operate beyond applications for which the machines are primarily engineered. Motor graders have for many years proven to be the most effective and efficient means for grading, distributing and leveling material in a variety of environments. While motor graders are also sometimes used in snow removal and related tasks, they tend to sit idle more often than desired. In other words, despite the tremendous success of the conventional motor grader design in performing certain types of work, there tend to be limitations to the suitability of motor graders for uses beyond certain basic tasks. The desirability of a means for adapting motor graders and the like to different operating environments, and for use in unconventional applications, has been recognized for some time.
One means for increasing the range of tasks which may be performed by motor graders has been through improvements to the means and methods for attaching work implements such as blades. It is typical for a motor grader to have a factory-installed implement system, which is typically disassembled only for service or replacement of the implement. Swapping implements on motor graders in the field has until recently been rare or unknown. Certain newer designs, however, contemplate switching the factory-installed implement for other devices in the field without substantial effort, rendering the motor grader amenable to different tasks, or providing greater flexibility even when used in conventional work. While increasing the number and type of implements that can be utilized by a motor grader promises to substantially broaden the use of these relatively large, and relatively expensive machines, new implement types and the hardware enabling such added flexibility introduce new challenges.
Many motor graders include an implement system that is highly maneuverable, permitting a conventional motor grader blade to be moved side-to-side, up and down, and the implement angle of attack and rotational position of the blade adjusted, for example. Where certain implements, such as hydraulically actuated implements, are to be mounted to and used by a motor grader, the substantial degree of flexibility in movement of the implement creates a challenge for supplying hydraulic power throughout the range of motion of the implement, as well as hydraulically actuated coupling hardware, where used. There is thus a need for an improved means of providing hydraulic power to implements configured for use with motor graders and the like.
The problems posed by hydraulically actuated devices and the like having a need for hydraulic power throughout a range of motion is a problem previously recognized in other technical areas. U.S. Pat. No. 4,384,619 to Schuck provides a hose tensioning device for a side shift plow assembly. Schuck states that a hose tensioning device can permit a relatively large amount of hydraulic hose for an implement control cylinder to be fed out or retracted for accommodating movement of a side shifting implement. In particular, Schuck utilizes a spring biased arm which engages with a flexible hose group carrying hydraulic fluid. Schuck is similar to other known hose tensioning devices, typically utilizing a tension spring or the like or a retraction reel to permit a large amount of hydraulic line to be positioned out of the way during moving or stowing a hydraulically actuated device. While Schuck and similar devices may provide improvements over simply allowing hydraulic lines to sag and potentially drag on the ground or be impinged upon by other components, feeding out and drawing in a relatively large amount of hydraulic line is inherently unwieldy and complex in design.
The present disclosure is directed to one or more of the problems or shortcomings set forth above.
In one aspect, the present disclosure provides a machine that includes a frame having a longitudinal axis and a front set of ground engaging elements and at least one back set of ground engaging elements. The machine further includes a coupler suspended below the frame and positioned between the front and back sets of ground engaging elements. The coupler is configured for mounting an implement thereon and movable between a first position and a second position defining a range of motion of the coupler transverse to the axis. The machine further includes a hydraulic system having a hydraulic circuit for providing hydraulic power to a hydraulically actuated device movable with the coupler throughout the range of motion of the coupler transverse to the axis, the hydraulic circuit including a flexible segment and a rigid support segment configured to support the flexible segment above a work surface. The rigid support segment is pivotable between an extended position and a stowed position corresponding to the first and second positions of the coupler, respectively.
In another aspect, the present disclosure provides a method of providing hydraulic power to a hydraulically actuated device of a machine having a frame with front and back sets of ground engaging elements. The method includes connecting a hydraulic circuit of the machine with a hydraulically actuated device movable via an implement coupler of the machine suspended below the frame and positioned between the front and back sets of ground engaging elements, the coupler being movable transverse to a longitudinal axis of the machine between a first position and a second position defining a range of motion of the coupler transverse to the longitudinal axis. The method further includes controlling positioning of fluid lines of the hydraulic circuit during moving the coupler between the first and second positions at least in part by pivoting a rigid support segment of the hydraulic circuit between a stowed position and an extended position corresponding to the first and second positions of the coupler, respectively, and supporting a flexible segment of the hydraulic circuit with the rigid support segment during pivoting the rigid support segment.
In still another aspect, the present disclosure provides a hydraulic system for an implement system of a machine having a frame with front and back sets of ground engaging elements. The hydraulic system includes a first hydraulic circuit segment including a supply passage and a return passage, and a second hydraulic circuit segment connected with the first hydraulic circuit segment, and also including a supply passage and a return passage fluidly connected with the supply passage and return passage, respectively, of the first hydraulic circuit segment. The first and second hydraulic circuit segments are configured for providing hydraulic power to a hydraulically actuated device movable with an implement coupler of the implement system throughout a range of motion of the coupler transverse to a longitudinal axis of the machine. A rigid support is coupled with the first hydraulic circuit segment and extends in parallel therewith, the rigid support being configured to support the second hydraulic circuit segment above a work surface during moving of the coupler between a first position and a second position defining the range of motion of the coupler. The rigid support is pivotable, between an extended position and a stowed position corresponding to the first and second positions of the coupler, respectively.
Referring to
An implement assembly 50 may be suspended below frame 12, and may include a drawbar 52 and circle 54, together comprising a drawbar and circle assembly. Coupler 18 may be a part of, and supported by implement assembly 50, and positioned between front and back ground engaging elements 15 and 17. In one embodiment, coupler 18 may include rails 43 enabling coupler 18 to slide back and forth transverse to a longitudinal axis of machine 10 between a first sideshift position and a second sideshift position, approximately in and out of the page in the
Referring also to
In
Hydraulic system 20 may comprise a hydraulic circuit 21 having a first segment 26 and a second segment 24, a first fluid line 35 that includes therein a fluid passage and a second fluid line 37 that also includes therein a fluid passage. Each of fluid lines 35 and 37 may extend from a first set of hydraulic connectors 53 mounted to circle 54, for example, to a second set of hydraulic connectors 51 which are mounted to coupler 18, for example. In embodiments where coupler 18 does not itself include a hydraulically actuated device, fluid lines 35 and 37 might extend directly to an implement such as implement 40 having device 42. First segment 26 may consist of a rigid support segment comprising a rigid support for second segment 24, which may comprise a flexible segment. First segment 26 is configured to support second segment 24 above a work surface during moving of coupler 18 between its first and second sideshift positions, preventing sagging of hydraulic circuit 21 and potential dragging against the ground or impingement by other components of machine 10. The present disclosure is particularly well-suited to the motor grader environment, due to proximity to the ground of line 35 and 37, and the typically relatively large amount of sideshift travel, in contrast to earlier lines routing strategies in different machine environments. Even in the motor grader context, certain earlier strategies relying on a large amount of vertical hose length, or different lines routing than that shown herein, are inferior in terms of complexity and their effects on the range of motion of the implement assembly components.
First segment 26 may be mounted to a pivot device or pin joint 28 which enables pivoting of first segment between an extended position, shown in solid lines in
Turning to
Those skilled in the art will appreciate that a wide variety of configurations for housing 33, line portions 35a and 37a, pivot device 28, etc. are possible, and the present description is illustrative only. Moreover, the specific configuration chosen will depend at least in part on the machine and implement system within which a hydraulic system according to the present disclosure is implemented. While first and second segments 26 and 24 are shown as having approximately equal lengths, their respective lengths might differ in other embodiments, depending upon the range of motion through which hydraulic power is to be provided. It will generally be desirable to avoid bending flexible second segment 24 beyond a manufacturer recommended hose radius lower limit. More than one fluid supply line and one fluid return line might also be used, for example where multiple hydraulically actuated devices are provided with hydraulic power in the present context. Still further, while the use of housing 33 as a rigid support for first segment 26 is contemplated to provide a practical implementation strategy, the present disclosure is not thereby limited, and rigid supply and return lines configured to pivot via pivot device 28 might be used as a rigid support apart from a dedicated housing structure.
Referring to the drawing Figures generally, when machine 10 executes certain operations, such as moving coupler 18 in directions transverse to axis A, the relative position of any hydraulically actuated devices mounted to or within coupler 18, and to or within implement 40, will change relative to the rest of machine 10. In particular, the distance between connectors 53 and 51 will tend to change as a result of sideshift movement of coupler 18 relative to the circle and drawbar assembly comprised of drawbar 52 and circle 54. Other adjustments of coupler 18 will also tend to affect this relative distance. Consequently, the distance spanned by segments 26 and 24 of hydraulic circuit 21 will also change.
The changing distance over which hydraulic power is to be supplied will be accommodated via pivoting of first segment 26 about pivot device 28. For instance, when coupler 18 is moved generally leftward and out of the page relative to the
The present disclosure provides substantial advantages over known systems for playing out and retracting lines, and will provide for increased use, application and versatility of motor grader and similar machines. Rather than requiring an unwieldy spool or other expensive, bulky and complex take-up apparatus, hydraulic system 20 is configured via only a modest amount of additional hardware, and relies primarily upon the use of a simple, rigid supporting portion of the hydraulic circuit itself to control positioning of other components of the circuit. The presently disclosed strategy is also especially well-suited to the motor grader environment, though not strictly limited thereto.
The present description is for illustrative purposes only, and should not be construed to narrow the breadth of the present disclosure in any way. Thus, those skilled in the art will appreciate that various modification might be made to the presently disclosed embodiments without departing from the intended spirit and scope of the present disclosure. For instance, the present disclosure has been described in the context of an articulated machine such as a motor grader, it is not thereby limited. Embodiments are contemplated wherein other machines such as those commonly used on construction sites and known as angled broom machines, having a dedicated purpose such as sweeping pavement with a relatively large, rotating brush, might be amenable to modification according to the present disclosure. In other words, devices such as angled brooms which formerly provided only one type of use, may be applied in other work environments to perform different tasks, by modification to use different implements in the manner described herein. Other aspects, features and advantages will be apparent upon an examination of the attached drawings and appended claims.
