Patent Application
20130000996
The present disclosure relates to mobile machines and, more particularly, to support systems of mobile machines.
Many machines are mobile machines configured to perform one or more tasks while travelling along a ground surface like a road surface or a terrain surface of the earth. Such mobile machines often include a support system with one or more ground-engaging components (e.g., track units, wheels, or skids) configured to move along the ground surface, as well as one or more linkages for connecting the ground-engaging components to a frame of the machine. Some support systems include linkages configured to allow moving a ground-engaging component of the machine between laterally inward and laterally outward positions.
For example, Published German Patent Application No. DE 102004059881 to Boehme et al. (“the '881 application”) discloses various embodiments of pivoting linkages for connecting a wheel or a track to a frame of a roadworking vehicle. The pivoting linkages of the '881 application allow pivoting the wheel or track between extended and retracted positions. Additionally, the pivoting linkages of the '881 patent include one or more telescopic links that allow adjusting the geometry of the linkage.
Although the '881 application discloses pivoting linkages that may be used to move a wheel or track of a mobile machine between an extended and a retracted position, certain disadvantages may persist. For example, many of the linkages disclosed by the '881 application may have an unnecessarily large number of link members arranged in unnecessarily complicated manners.
The disclosed embodiments may solve one or more of the foregoing problems.
One disclosed embodiment relates to a mobile machine. The mobile machine may include a frame and a support system for supporting the frame from a ground surface underlying the support system. The support system may include a swing member pivotally engaged to the frame. The support system may also include journal structure rigidly attached to the swing member. The support system may further include a strut engaged to the journal structure in a manner allowing rotation of the strut relative to the journal structure about a central axis of the strut. Additionally, the support system may include a ground-engaging component mounted to the strut, the ground-engaging component being configured to move along the ground surface. The support system may also include a steering actuator engaged to the frame and the strut to control rotation of the strut about its central axis and thereby control a steering angle of the ground-engaging device relative to the frame.
Another embodiment relates to a mobile machine. The mobile machine may include a frame and a support system for supporting the frame from a ground surface underlying the support system. The support system may include a swing member pivotally engaged to the frame. The support system may also include a ground-engaging component pivotally engaged to the swing member, the ground-engaging component being configured to move along the ground surface. The support system may also include a first actuator connected to the swing member to pivot the swing member relative to the frame, the first actuator being disposed in a first plane. Additionally, the support system may include a second actuator operable to steer the ground-engaging component by pivoting the ground-engaging component relative to the swing member, the second actuator being disposed in a second plane.
A further disclosed embodiment relates to a method of supporting the frame of a mobile machine from a ground surface and steering the mobile machine along the ground surface. The method may include at least partially supporting the frame with a swing member pivotally engaged to the frame, the swing member being rigidly engaged to journal structure. The method may also include at least partially supporting the swing member with a strut engaged to the journal structure in a manner allowing rotation of the strut relative to the swing member about a central axis of the strut. Additionally, the method may include at least partially supporting the strut with a ground-engaging component mounted to the strut, the ground-engaging component being configured to move along the ground surface. The method may also include steering the ground-engaging component by controlling rotation of the ground-engaging component and the strut about a central axis of the strut with a steering actuator engaged to the frame and the strut.
Machine 10 may be configured to perform various functions when travelling ground surface 12. In the embodiment shown in
Machine 10 may include a frame 14. Frame 14 may serve to tie together and support the other components and systems of machine 10. In addition to frame 14, machine 10 may have various other components and systems that serve various purposes. For example, where machine 10 is a cold planer or road reclaimer, machine 10 may include a grinding mechanism (not shown) configured to grind off a top layer of ground surface 12. Such a grinding mechanism may include, for example, a rotor (not shown) with cutting tools (not shown), such as teeth, for cutting and grinding the top layer of ground surface 12. Such a grinding mechanism may be disposed in various places on machine 10. For example, the grinding mechanism may be housed in a rear, lower portion 22 of machine 10. Alternatively or additionally, machine 10 may include one or more grinding mechanisms located in middle and/or forward positions. Machine 10 may also include a conveyor 86 configured to receive material removed from ground surface 12 by the grinding mechanism and convey that material to a receiver, such as a truck.
Machine 10 may also include one or more power sources (not shown) for powering the grinding mechanism, conveyor 86, and/or various other components and systems of machine 10. For example, machine 10 may include one or more internal combustion engines, batteries, fuel cells, or the like for providing power. Machine 10 may also include various provisions for transmitting power from such power sources to the grinding mechanism and/or various other components of the machine. For example, where machine 10 includes an internal combustion engine as a power source, machine 10 may include one or more mechanical or electrical power-transmission devices, such as, mechanical transmissions, hydraulic pumps and motors, and/or electric generators and motors, for transmitting power from the engine to the grinding mechanism and conveyor 86.
To support it from ground surface 12 and steer it as it moves along ground surface 12, machine 10 may include a support system 16 and a steering system 30. Support system 16 may include one or more front ground-engaging components 18 and one or more rear ground-engaging components 20 configured to move along ground surface 12.
Support system 16 may include various components connecting frame 14 to ground engaging components 18, 20 in a manner to support machine 10 from ground engaging components 18, 20. As
The engagement between strut 26 and frame 14 may also be such to allow rotation of strut 26, undercarriage bracket 24, and ground-engaging component 18 about a vertical axis 32 relative to frame 14. This rotation capability may allow steering ground-engaging component 18 and, thus, machine 10. Steering system 30 may have one or more actuators (not shown) for controlling the rotation of strut 26, undercarriage bracket 24, and ground-engaging component 18 about vertical axis 32.
Similar to the components connecting front ground-engaging component 18 to frame 14, support system 16 may include an undercarriage bracket 34 and a strut 36 supported from rear ground-engaging component 20. Support system 16 may also include a linkage system 38 connecting strut 36 to frame 14. Details of linkage system 38, strut 36, undercarriage bracket 34, and rear ground-engaging component 20 can be better seen in
Linkage system 38 may be configured to allow horizontal translation of rear ground-engaging component 20, as well as rotation of rear ground-engaging component 20 about a vertical axis 52 for steering purposes.
Linkage system 38 may be configured to transmit at least a portion of the weight carried by rear ground-engaging component 20 from frame 14, through swing member 40, strut 36, and undercarriage bracket 34, to ground-engaging component 20. As best shown in
In some embodiments, machine 10 may include other features that may help transmit forces and loads between swing member 40 and frame 14. For example, machine 10 may include one more moveable locking pins (not shown) for selective connection between swing member 40 and frame 14 to restrain relative movement between swing member 40 and frame 14 in one or more manners. One such moveable locking pin may include a vertically extending pin attached to frame 14 at a position below swing member 40 and at a distance from axis 58. This locking pin may be configured to move vertically between a position disengaged from swing member 40 and a position engaged to swing member 40 (such as through a hole in swing member 40). When such a locking pin is disengaged from swing member 40, it may present no restriction on the motion of swing member 40. On the other hand, when such a locking pin is engaged to swing member 40, it may restrain swing member 40 from pivoting about axis 58. Additionally, when engaged to swing member 40, such a locking pin may also assist pin joint 54 in carrying vertical loads and/or moments about horizontal axes.
Rings 88, 90 may be connected to upper and lower plates 92, 94. Ring 88 may be disposed between upper and lower plates 92, 94 adjacent outer end 62 of swing member 40. Ring 88 may be concentric with axis 52 and, thus, aligned with openings 102, 106. In some embodiments, ring 88 may be rigidly attached to both upper and lower plates 92, 94. For example, ring 88 may be welded to upper and lower plates 92, 94, rigidly fastened to upper and lower plates 92, 94, or integrally formed (e.g., cast) with upper and lower plates 92, 94. Ring 90 may be disposed above upper plate 92. Ring 90 may also be substantially concentric with axis 52 and, thus, aligned with openings 102 and 106. Additionally, ring 90 may be rigidly attached to upper plate 92. For example, ring 90 may be welded to upper plate 92, rigidly fastened to upper plate 92, or integrally formed (e.g., cast) with upper plate 92, 94. The opening in each of rings 88, 90 may be large enough for strut 36 to pass through them. In addition to upper and lower plates 92, 94 and rings 88, 90, swing member 40 may include various other components engaged to one another in various ways.
A tube 96 may be attached to outer end 62 of swing member 40. For example, tube 96 may be attached to ring 90, such as by fasteners. The interior bore of tube 96 may extend concentric with axis 52. Additionally, the interior bore of tube 96 may be large enough to receive strut 36. As best shown in
Like the engagement between frame 14 and swing member 40, the engagement between swing member 40 and strut 36 may allow transmission of substantial vertical loads and horizontal moments between swing member 40 and strut 36. For example, swing member 40 and strut 36 may be engaged to one another in a manner allowing strut 36 to rotate about vertical axis 52, which may coincide with a central axis of strut 36.
Swing member 40, journal structure 60, and strut 36 may be constructed and engaged to one another in various ways that provide rigid connection of journal structure 60 to swing member 40 and rotational engagement of strut 36 to journal structure 60. Strut 36 may include a circular, vertically extending shaft rotatably engaged to journal structure 60. Journal structure 60 may be part of swing member 40 itself or a separate component attached to swing member 40. In the embodiment shown in
Strut 36 may also be connected to undercarriage bracket 34 in a manner allowing transmission of substantial vertical loads and horizontal moments between the two. For example, a lower end 64 of strut 36 may be rigidly engaged to undercarriage bracket 34. This fixed engagement may be effected by any suitable means, including welding, fasteners, and/or integral construction.
Undercarriage bracket 34 may be connected to ground-engaging component 20 in various ways that allow transfer of weight and horizontal forces and moments between the two components. For example, as best shown in
The configuration of linkage system 38 shown in the figures and discussed above may allow undercarriage bracket 34, strut 36, journal structure 60, and swing member 40 to bear most of the loads on ground-engaging component 20 without substantial assistance from any other components. Because each of the joints between these structures can transmit moments about horizontal axes, these structures may be able to support the horizontal moments that arise from transmitting the weight of machine 14 between inner end 56 of swing member 40 and ground-engaging component 20. Also due to their ability to carry moments about horizontal axes, the joints between these structures may be able to support horizontal moments arising from transmission of horizontal forces from ground-engaging component 20 to inner end 56 of swing member 40. Because of the substantial length of swing member 40 and strut 36, these horizontal moments may be particularly large at the connection between swing member 40 and strut 36. Advantageously, the disclosed robust, rigid connection between swing member 40 and journal structure 60 may allow transmission of such large moments through strut 36 and swing member 40 to frame 14.
With swing member 40, journal structure 60, strut 36, and undercarriage component 34 addressing all horizontal moments, swing actuator 44 and steering actuator 50 may address moments about vertical axes 58 and 52, respectively. Swing actuator 44 may be any type of component configured and engaged to machine 10 in a manner allowing it to control the rotation of swing member 40 around vertical axis 58. For example, as best shown in
Steering actuator 50 may be configured and engaged to machine 10 in any manner allowing steering actuator 50 to control the angular orientation of strut 36 about vertical axis 52. In some embodiments, steering actuator 50 may be a hydraulic cylinder connected between frame 14 and strut 36. As best shown in
The orientation of swing member 40 and the steering angle of ground-engaging component 20 may interrelate in manners that depend on the geometric relationships between the lengths of the various members and actuators and the locations of the various pin joints and axes of linkage system 38. The disclosed approach of connecting steering actuator 50 directly to frame 14 may enable configuring the geometry of linkage system 38 in a manner that reduces steering angle disturbances resulting from movement of swing member 40. For example, as best shown in
While
Machine 10 may include various components for controlling swing actuator 44 and steering actuator 50 to control the lateral position and steering angle of ground-engaging component 20. To receive operator inputs regarding a desired position and steering angle of ground-engaging components, machine 10 may include one or more operator-input devices. For example, as
In addition to the components and systems mentioned above, machine 10 may have various other components and systems. For example, machine 10 may include a propulsion system for moving it along ground surface 12. In some embodiments, such a propulsion system may include one or more components for driving ground-engaging components 18, 20 to propel machine 10. For instance, where machine 10 includes a hydraulic pump (not shown) driven by a power source (not shown), machine 10 may include one or more hydraulic motors (not shown) drivingly connected to ground-engaging components 18, 20 to propel machine 10.
Machine 10 and support system 16 are not limited to the configuration shown in
Machine 10 and support system 16 may have use in any application where one or more tasks may be performed by moving machine 10 along ground surface 12. For example, where machine 10 is a cold planer or a road reclaimer, machine 10 may have use for grinding a layer of asphalt, concrete, or the like off of ground surface 12. This may be done, for example, in preparation to lay a new cover of asphalt, concrete, or the like.
While operating machine 10 to grind a layer of material from ground surface 12, an operator may control the propulsion system to move machine 10 forward, while manipulating steering input 84 to control the direction machine 10 travels. Based on the operator's manipulation of steering input 84, steering system 30 may control the rotation of front ground-engaging component 18 about vertical axis 32 and/or the rotation of rear ground-engaging component 20 about vertical axis 52. Referring to
While machine 10 is moving forward with steering system 30 controlling the direction of ground-engaging components 18, 20, rear ground-engaging component 20 may be positioned in the laterally inner position shown in
To position ground-engaging component 20 in the laterally outer position shown in
As noted above, steering actuator 50 may be engaged to frame 14 and steering member 48 in positions such that a given length of steering actuator 50 provides the same steering angle of ground-engaging component 20 in the laterally inner and laterally outer position. For example, steering actuator 50 has the same length in both
The disclosed configurations of linkage system 38 may also provide a number of other advantages. For example, the ability of linkage system 38 to transfer substantially all horizontal moments to frame 14 through a single member, specifically swing member 40, may promote simplicity of linkage system 38 by obviating the use of other rigid members to help carry these horizontal moments. Additionally, placing swing member 40 and swing actuator 44 in one horizontal plane, and placing steering actuator 50 and steering member 48 in another horizontal plane may help save space on machine 10. As shown in
Operation of support system 16 and steering system 30 are not limited to the examples discussed above. For example, while the foregoing discusses moving the rear of machine 10 to the left by contracting steering actuator 50 and moving machine 10 to the right by extending steering actuator 50, these movements may be reversed in some embodiments having different positioning and geometries of steering member 48 and steering actuator 50. Similarly, while the examples discussed above include extending swing actuator 44 to position swing member 40 in the laterally inner position and contracting swing actuator 44 to position swing member 40 in the laterally outer position, these movements may be reversed in embodiments having different positioning and/or geometry of swing member 40 and swing actuator 44.
It will be apparent to those skilled in the art that various modifications and variations can be made in the disclosed systems and methods without departing from the scope of the disclosure. Other embodiments of the disclosed systems and methods will be apparent to those skilled in the art from consideration of the specification and practice of the systems and methods disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims and their equivalents.
