Operator platform suspension with adjustable height

Abstract

A platform assembly (300) is configured for attachment to a power machine (100, 200). The assembly includes first and second upper arms (304), first and second lower arms (308), first and second shock absorbers (310), and a platform structure. Each of the first and second upper arms (304) has a first pivot joint (302) configured for attachment to the power machine and an opposed second pivot joint (316). Each of the first and second lower arms (308) has a third pivot joint (306) configured for attachment to the power machine and an opposed fourth pivot joint (316). Each of the first and second shock absorbers (310) is pivotally attached to a respective upper arm (304) between its first pivot joint (302) and its second pivot joint (316), and is pivotally attached to a respective lower arm (308) between its third pivot joint (306) and its fourth pivot joint (316). The platform structure is attached to the four arms (304, 308) at the second and fourth pivot joints (316).

Description

OPERATOR PLATFORM SUSPENSION WITH ADJUSTABLE HEIGHTBACKGROUND

[0001] This disclosure is directed toward power machines. Power machines, for the purposes of this disclosure, include any type of machine that generates power to accomplish a particular task or a variety of tasks. One type of power machine is a work vehicle. Work vehicles are generally self-propelled vehicles that have a work device, such as a lift arm (although some work vehicles can have other work devices) that can be manipulated to perform a work function. Work vehicles include excavators, loaders, utility vehicles, tractors, and trenchers, to name a few examples.

[0002] The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.SUMMARY

[0003] In one aspect, a platform assembly is configured for attachment to a power machine. In an exemplary embodiment, the assembly comprises first and second upper arms, first and second lower arms, first and second shock absorbers, and a platform structure. In an exemplary embodiment, each of the first and second upper arms has a first pivot joint configured for attachment to the power machine and an opposed second pivot joint. In an exemplary embodiment, each of the first and second lower arms has a third pivot joint configured for attachment to the power machine and an opposed fourth pivot joint. In an exemplary embodiment, the first shock absorber is pivotally attached to the first upper arm between its first pivot joint and its second pivot joint. In an exemplary embodiment, the first shock absorber is pivotally attached to the first lower arm between its third pivot joint and its fourth pivot joint. In an exemplary embodiment, the second shock absorber is pivotally attached to the second upper arm between its first pivot joint and its second pivot joint, and is pivotally attached to the second lower arm between its third pivot joint and its fourth pivot joint. In an exemplary embodiment, the platform structure is attached to the first and second upper arms at the second pivot joints and the first and second lower arms at the fourth pivot joints. In another aspect, an exemplary method of using a platform assembly on apower machine comprises adjusting a spring rate of at least one of the first or second shock absorbers and / or an elevation of the platform structure relative to the power machine.

[0004] This summary and the Abstract are provided to introduce concepts in simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features or essential features of the disclosed or claimed subject matter and is not intended to describe each disclosed embodiment or every implementation of the disclosed or claimed subject matter. Specifically, features disclosed herein with respect to one embodiment may be equally applicable to another. Further, this summary is not intended to be used as an aid in determining the scope of the claimed subject matter. Many other novel advantages, features, and relationships will become apparent as this description proceeds. The figures and the description that follow more particularly exemplify illustrative embodiments.BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The disclosed subject matter will be further explained with reference to the attached figures, wherein like structure or system elements are referred to by like reference numerals throughout the several views. All descriptions are applicable to like and analogous structures throughout the several embodiments, unless otherwise specified.

[0006] FIG. 1 is a block diagram illustrating functional systems of a representative power machine on which embodiments of the present disclosure can be practiced.

[0007] FIG. 2 is a front perspective view of a representative power machine in the form of a mini track loader of a type on which the disclosed embodiments can be practiced.

[0008] FIG. 3 is a rear perspective view of the representative power machine.

[0009] FIG. 4 is a rear perspective view of a frame of the representative power machine, including an exemplary platform suspension assembly.

[0010] FIG. 5 is similar to FIG. 4 but shows the machine frame from a lower rear perspective viewpoint.

[0011] FIG. 6 is a side perspective view of a first exemplary embodiment of a platform suspension assembly.

[0012] FIG. 7 is a side perspective view of a second exemplary embodiment of a platform suspension assembly.

[0013] FIG. 8 is a side perspective view of the second exemplary platform suspension assembly with its pneumatic cylinder shock absorbers in a retracted configuration, thereby resulting in a lower platform elevation.

[0014] FIG. 9 is a side perspective view of the second exemplary platform suspension assembly, with the pneumatic cylinder shock absorbers in an extended configuration, thereby raising an elevation of the platform.

[0015] FIG. 10 is a side elevation view of the platform suspension assembly attached to a power machine, with the platform in a relatively raised position.

[0016] FIG. 11 is a side elevation view of the platform suspension assembly attached to a power machine, with the platform in a relatively lowered position.

[0017] FIG. 12 is a partial rear perspective view of a machine with an exemplary platform assembly and an attached hip pad assembly at a relatively raised elevation.

[0018] FIG. 13 is a partial rear perspective view of a machine with an exemplary platform assembly and an attached hip pad assembly at a relatively lowered elevation.

[0019] FIG. 14 is a rear perspective view of the exemplary platform assembly and an attached hip pad assembly.

[0020] FIG. 15 is a front perspective view of the exemplary platform assembly and an attached hip pad assembly.

[0021] While the above-identified figures set forth one or more embodiments of the disclosed subject matter, other embodiments are also contemplated, as noted in the disclosure. In all cases, this disclosure presents the disclosed subject matter by way of representation and not limitation. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that fall within the scope of the principles of this disclosure.

[0022] The figures may not be drawn to scale. In particular, some features may be enlarged relative to other features for clarity. Moreover, where terms such as above, below, over, under, top, bottom, side, right, left, vertical, horizontal, etc., are used, it is to be understood that they are used only for ease of understanding the description. It is contemplated that structures may be oriented otherwise.

[0023] The terminology used herein is for the purpose of describing embodiments, and the terminology is not intended to be limiting. Unless indicated otherwise, ordinal numbers (e.g., first,second, third, etc.) are used to distinguish or identify different elements or steps in a group of elements or steps and do not supply a serial or numerical limitation on the elements or steps of the embodiments thereof. For example, "first," "second," and "third" elements or steps need not necessarily appear in that order, and the embodiments thereof need not necessarily be limited to three elements or steps. Unless indicated otherwise, any labels such as "left," "right," "front," "back," "top," "bottom," "forward," "reverse," "clockwise," "counter clockwise," "up," "down," or other similar terms such as "upper," "lower," "aft," "fore," "vertical," "horizontal," "proximal," "distal," "intermediate" and the like are used for convenience and are not intended to imply, for example, any particular fixed location, orientation, or direction. Instead, such labels are used to reflect, for example, relative location, orientation, or directions. The singular forms of "a," "an," and "the" include plural references unless the context clearly dictates otherwise.DETAILED DESCRIPTION

[0024] The concepts disclosed in this discussion are described and illustrated with reference to exemplary embodiments. These concepts, however, are not limited in their application to the details of construction and the arrangement of components in the illustrative embodiments and are capable of being practiced or being carried out in various other ways. The terminology in this document is used for description and should not be regarded as limiting. Words such as “including,” “comprising,” and “having” and variations thereof as used herein are meant to encompass the items listed thereafter, equivalents thereof, as well as additional items.

[0025] A representative power machine on which the embodiments can be practiced is illustrated in diagram form in FIG. 1 and one example of such a power machine is illustrated in FIGS. 2 and 3. For the sake of brevity, only one power machine is discussed. However, the disclosed teachings can be practiced on any of a number of power machines, including power machines of different types from the representative, illustrated power machine. Power machines, for the purposes of this discussion, include a frame, at least one work element, and a power source that can provide power to the work element to accomplish a work task. One type of power machine is a self-propelled work vehicle. Self-propelled work vehicles are a class of power machines that include a frame, work element, and a power source that can provide power to the work element. At least one of the work elements is a motive system for moving the power machine under power.

[0026] Referring now to FIG. 1, a block diagram illustrates the basic systems of a power machine 100 upon which the embodiments discussed below can be advantageously incorporated and can be any of several distinct types of power machines. The block diagram of FIG. 1 identifies various systems on power machine 100 and the relationship between various components and systems. As mentioned above, at the most basic level, power machines for the purposes of this discussion include a frame, a power source, and a work element. The power machine 100 has a frame 110, a power source 120, and a work element 130. Because power machine 100 shown in FIG. 1 is a self-propelled work vehicle, it also has tractive elements 140, which are themselves work elements provided to move the power machine over a support surface and an operator station 150 that provides an operating position for controlling the work elements of the power machine. A control system 160 is provided to interact with the other systems to perform various work tasks at least in part in response to control signals provided by an operator.

[0027] Certain work vehicles have work elements that can perform a dedicated task. For example, some work vehicles have a lift arm structure to which an implement 180 such as a bucket is attached such as by a pinning arrangement. The work element, i.e., the lift arm structure can be manipulated to position the implement 180 for performing the task. The implement 180, in some instances can be positioned relative to the work element, such as by rotating a bucket relative to a lift arm structure, to further position the implement. Under normal operation of such a work vehicle, the bucket is intended to be attached and under use. Such work vehicles may be able to accept other implements by disassembling the implement / work element combination and reassembling another implement in place of the original bucket. Other work vehicles, however, are intended to be used with a wide variety of implements and have an implement interface such as implement interface 170 shown in FIG. 1. At its most basic, implement interface 170 is a connection mechanism between the frame 110 or a work clement 130 and an implement 180, which can be as simple as a connection point for attaching an implement directly to the frame 110 or a work element 130 or more complex, as discussed below.

[0028] On some power machines, implement interface 170 can include an implement carrier, which is a physical structure movably attached to a work element. The implement carrier has engagement features and locking features to accept and secure any of several implements to the work element. One characteristic of such an implement carrier is that once an implement isattached to it, it is fixed to the implement (i.e., not movable with respect to the implement) and when the implement carrier is moved with respect to the work element, the implement moves with the implement carrier. The term “implement carrier” is not merely a pivotal connection point, but rather a dedicated device specifically intended to accept and be secured to various different implements. The implement carrier itself is mountable to a work element 130 such as a lift arm structure or the frame 110. Implement interface 170 can also include one or more power sources for providing power to one or more work elements on an implement. Some power machines can have a plurality of work element with implement interfaces, each of which may, but need not, have an implement carrier for receiving implements. Some other power machines can have a work element with a plurality of implement interfaces so that a single work element can accept a plurality of implements simultaneously. Each of these implement interfaces can, but need not, have an implement carrier.

[0029] Frame 110 includes a physical structure that can support various other components that are attached thereto or positioned thereon. The frame 110 can include any number of individual components. Some power machines have frames that are rigid. That is, no part of the frame is movable with respect to another part of the frame. Other power machines have at least one portion that can move with respect to another portion of the frame. For example, excavators can have an upper frame portion that rotates about a swivel with respect to a lower frame portion. Other work vehicles have articulated frames such that one portion of the frame pivots with respect to another portion for accomplishing steering functions.

[0030] Frame 110 supports the power source 120, which can provide power to one or more work elements 130 including the one or more tractive elements 140, as well as, in some instances, providing power for use by an attached implement via implement interface 170. Power from the power source 120 can be provided directly to any of the work elements 130, tractive elements 140, and implement interfaces 170. Alternatively, power from the power source 120 can be provided to a control system 160, which in turn selectively provides power to the elements that are capable of using it to perform a work function. Power sources for power machines frequently include an engine such as an internal combustion engine and a power conversion system such as a mechanical transmission or a hydraulic system that can convert the output from an engine into a form of power that is usable by a work element. Other types of power sources can be incorporated into powermachines, including electrical sources or a combination of power sources, known generally as hybrid power sources.

[0031] FIG. 1 shows a single work element designated as work element 130, but various power machines can have any number of work elements. Work elements are typically attached to the frame of the power machine and movable with respect to the frame when performing a work task. In addition, tractive elements 140 are a special case of work element in that their work function is generally to move the power machine 100 over a support surface. Tractive elements 140 are shown separate from the work element 130 because many power machines have additional work elements besides tractive elements, although that is not always the case. Power machines can have any number of tractive elements, some or all of which can receive power from the power source 120 to propel the power machine 100. Tractive elements can be, for example, wheels attached to an axle, track assemblies, and the like. Tractive elements can be rigidly mounted to the frame such that movement of the tractive element is limited to rotation about an axle or steerably mounted to the frame to accomplish steering by pivoting the tractive element with respect to the frame.

[0032] Power machine 100 includes an operator station 150, which provides a position from which an operator can control operation of the power machine. In some power machines, the operator station 150 is defined by an enclosed or partially enclosed cab. Some power machines on which the disclosed embodiments may be practiced may not have a cab or an operator compartment of the type described above. For example, a walk behind loader may not have a cab or an operator compartment, but rather an operating position that serves as an operator station from which the power machine is properly operated. More broadly, power machines other than work vehicles may have operator stations that are not necessarily similar to the operating positions and operator compartments referenced above. Further, some power machines such as power machine 100 and others, whether they have operator compartments or operator positions, may be capable of being operated remotely (i.e. , from a remotely located operator station) instead of or in addition to an operator station adjacent or on the power machine. This can include applications where at least some of the operator-controlled functions of the power machine can be operated from an operating position associated with an implement that is coupled to the power machine. Alternatively, with some power machines, a remote-control device can be provided (i.e., remotefrom both of the power machine and any implement to which is it coupled) that can control at least some of the operator-controlled functions on the power machine.

[0033] FIGS. 2-3 illustrate a loader 200, which is one particular example of a power machine of the type illustrated in FIG. 1 in which the embodiments discussed below can be advantageously employed. The loader 200 is a tracked loader and more particularly, a mini-loader. A mini-loader for the purposes of this discussion is a small loader relative to other compact loaders such as traditional skid-steer loaders and compact track loaders; typically, a mini-loader does not have an enclosed operator cab. Some mini-loaders have a platform on which an operator can ride, which serves as operator station 150. Other mini-loaders can be operated by an operator who walks behind the loader. Still other mini-loaders have a platform that is moveable or removable to allow an operator to alternatively ride on the platform or walk behind the loader. The illustrated loader 200 is a tracked loader, though in some embodiments, the tractive elements 140 can be wheels.

[0034] The loader 200 should not be considered limiting, especially as to features that the loader 200 may have described herein that are not essential to the disclosed embodiments. Such features may or may not be included in power machines other than the loader 200 upon which the embodiments disclosed below may be advantageously practiced. Unless specifically noted otherwise, embodiments disclosed below can be practiced on a variety of power machines, with the loader 200 being only one of those power machines. For example, some or all of the concepts discussed below can be practiced on many other types of stand-on work vehicles such as mowers, aerators, and spreaders, to name but a few examples. Moreover, while the illustrated embodiment shows a platform configured for a standing operator, the described platform suspension system can also be used for a seating platform, for example.

[0035] In an exemplary embodiment, loader 200 includes frame 210. The frame 210 supports a power system 220, the power system 220 being configured to generate or otherwise provide power for operating various functions on the power machine. The frame 210 also supports a work element in the form of a lift arm structure 230 that is selectively powered by the power system 220 in response to signals from an operator control system 260 and can perform various work tasks. The lift arm structure 230 in turn supports an implement carrier 272, which is configured to receive and secure various implements to the loader 200 for performing various work tasks. The loader 200 can be operated from an operator station 250 from which an operatorcan manipulate various control devices to cause the power machine to perform various functions, discussed in more detail below. In an exemplary embodiment, the frame 210 also supports a traction system 240, which is also selectively powered by the power system 220 in response to signals from the operator control system 260. The traction system 240 is configured to propel the power machine over a support surface.

[0036] Various power machines that can include and / or interact with the structures and / or functions of embodiments discussed below can have various frame components that support various work elements. The elements of frame 210 discussed herein are provided for illustrative purposes and are not necessarily the only type of frame that a power machine on which the embodiments discussed below can be practiced can be employed, unless otherwise specifically indicated. The frame 210 of the loader 200 includes an undercarriage or lower portion 211of the frame and a mainframe or upper portion 212 of the frame that is supported by the undercarriage. The mainframe 212 of the loader 200 is attached to the undercarriage 211 such as with fasteners or by welding the undercarriage to the mainframe. The mainframe 212 includes a pair of upright portions 214 located on either side and toward the rear of the mainframe that support the lift arm structure 230 and to which the lift arm structure 230 is pivotally attached. The lift arm structure 230 is illustratively pinned to each of the upright portions 214. The combination of mounting features on the upright portions 214 and the lift arm structure 230 and mounting hardware (including pins used to pin the lift ami structure to the mainframe 212) are collectively referred to as joints 216 (one is located on each of the upright portions 214) for the purposes of this discussion. The joints 216 are aligned along an axis 218 so that the lift arm structure is capable of pivoting, as discussed below, with respect to the frame 210 about axis 218. Other power machines may not include upright portions on either side of the frame or may not have a lift arm structure that is mountable to upright portions on cither side and toward the rear of the frame. For example, some power machines may have a single arm, mounted to a single side of the power machine or to a front or rear end of the power machine. Other machines can have a plurality of work elements, including a plurality of lift arms, each of which is mounted to the machine in its own configuration. The frame 210 also supports a pair of tractive elements 242 on either side of the loader 200, which on the loader 200 are track assemblies.

[0037] The lift arm structure 230 shown in FIGS. 2-3 is one example of a lift arm structure that can be attached to a power machine such as the loader 200 or other power machines on which embodiments of the present discussion can be practiced. The lift arm structure 230 has a set of lift arms 232 that are disposed on opposing sides of the frame 210. (It should be noted, however, that a lift arm structure may incorporate only a single lift arm or exhibit other configurations.) A first end 232A of each of the lift arms 232 is pivotally coupled to the power machine at joints 216 and a second end 232B of each of the lift arms is positioned forward of the frame 210 when in a lowered position as shown in FIG. 2. The lift am structure 230 is moveable (i.e., the lift arm structure can be raised and lowered) under control of the loader 200 with respect to the frame 210. That movement (i.e., the raising and lowering of the lift arm structure 230) is described by a radial travel path, shown generally by arrow 233. For the purposes of this discussion, the travel path 233 of the lift arm structure 230 is defined by the path of movement of the second end 232B of the lift arm structure.

[0038] The lift arms 232 are each coupled to a cross member 236 that provides increased structural stability to the lift arm structure 230. A pair of actuators 238, which on loader 200 can be hydraulic cylinders configured to selectively receive pressurized fluid from power system 220, are pivotally coupled to both the frame 210 and the lift arms 232 at pivotable joints 238A and 238B, respectively, on either side of the loader 200. The actuators 238 are sometimes referred to individually and collectively as lift cylinders. Actuators 238 can instead be other types of actuators, such as electric actuators. Actuation (i.e., extension and retraction) of the actuators 238 causes the lift arm structure 230 to pivot about joints 216 and thereby be raised and lowered along a fixed path illustrated by arrow 233. The lift arm structure 230 shown in FIGS. 2- 3 is representative of one type of lift arm structure that may be coupled to the power machine 200. Other lift arm structures, with different geometries, components, and arrangements can be pivotally coupled to the loader 200 or other power machines upon which the embodiments discussed herein can be practiced without departing from the scope of the present discussion. For example, other machines can have lift arm structures with lift arms that each have two portions (as opposed to the single piece lift arms 232) that are pivotally coupled to each other along with a control arm to create a four-bar linkage and a substantially vertical travel path or at least more vertical than the radial path of lift arm structure 230. Other lift arm structures can have anextendable or telescoping lift arm. Still other lift arm structures can have several (i.e. more than two) portions segments or portions. Some lift arms, most notably lift arms on excavators but also possible on loaders, may have portions that are controllable to pivot with respect to another segment instead of moving in concert (i.e., along a pre-determined path) as is the case in the lift arm structure 230 shown in FIGS. 2-3. Some power machines have lift arm structures with a single lift arm, such as is known in excavators or even some loaders and other power machines. Other power machines can have a plurality of lift arm structures, each being independent of the other(s).

[0039] An example of an implement interface 270 is provided at the second end 232B of the lift arms 232, as shown in FIG. 2. The implement interface 270 includes the implement carrier 272 that is configured to accept and secure a variety of different implements to the lift arm structure 230. Such implements have a machine interface that is configured to be engaged with the implement carrier 272. The implement carrier 272 is pivotally mounted to the second end 232B of each of the arms 232. An implement carrier actuator 237 is operably coupled to the lift arm structure 230 and the implement carrier 272 and is operable to rotate the implement carrier with respect to the lift arm structure 230. Other examples of power machines can have a plurality of implement carrier actuators. Still other examples of power machines of the type that can advantageously employ the disclosed embodiments discussed herein may not have an implement carrier such as implement carrier 272, but instead may allow only for implements to be directly attached to its lift arm structure such as by pinning.

[0040] The implement interface 270 also includes an implement power source 235 available for connection to an implement on the lift arm structure 230. The implement power source 235 can include pressurized hydraulic fluid ports to which an implement can be coupled. The pressurized hydraulic fluid ports selectively provide pressurized hydraulic fluid for powering one or more functions or actuators on an implement. The implement power source can, but need not, also or alternatively include an electrical power source for powering electrical actuators and / or an electronic controller on an implement. An electrical power source can also include electrical conduits that are in communication with a data bus on the loader 200 to allow communication between a controller on an implement and electronic devices on the loader 200.

[0041] The lower frame portion 211 supports a pair of attached tractive elements, identified in FIGS. 2-3 as left track assembly 242A and right track assembly 242B (collectivelytractive elements 242). Each of the tractive elements 242 has a track frame 243 that is coupled to the frame 210. The track frame 243 supports and is surrounded by an endless track 244, which rotates under power to propel the loader 200 over a support surface. Various elements are coupled to or otherwise supported by the track frame 243 for engaging and supporting the endless track 244 and cause it to rotate about the track frame 243. For example, a sprocket 246 is supported by the track frame 243 and engages the endless track 244 to cause the endless track to rotate about the track frame. An idler 245 is held against the track 244 by a tensioner (not shown) to maintain proper tension on the track 244. The track frame 243 also supports a plurality of rollers 248, which engage the track and, through the track, the support surface on which the weight of the loader 200 is distributed.

[0042] The operator station 250 is positioned toward the rear of the frame 210. While an operator stands on the platform 252, the operator has access to a plurality of operator control inputs 262 that, when manipulated by the operator, can provide control signals to control work functions of the power machine 200, including, for example, the traction system 240 and the lift arm 230. Operator control inputs 262 can include joysticks, switches, buttons, knobs, levers, variable sliders, roller-ball inputs and other multi-axis input devices, for example. In the embodiment shown in FIGS. 2-3, the operator station 250 is open to the back of the power machine 200. Similar other power machines, including other mini-loaders, can include operator stations toward the rear of the respective frames, without necessarily being open to the back of the power machines.

[0043] Display devices 264 are provided in the operator station to give indications of information relatable to the operation of the power machines in a form that can be sensed by an operator, such as, for example audible and / or visual indications. Audible indications can be made in the form of buzzers, bells, and the like or via verbal communication. Visual indications can be made in the form of graphs, lights, icons, gauges, alphanumeric characters, and the like. Displays can be designed to provide dedicated indications, such as warning lights or gauges, or dynamic to provide programmable information, including programmable display devices such as monitors of various sizes and capabilities. Display devices can provide diagnostic information, troubleshooting information, instructional information, and various other types of information that assists anoperator with operation of the power machine or an implement coupled to the power machine. Other information that may be useful for an operator can also be provided.

[0044] Frame 210 supports and generally encloses the power system 220 so that the various components of the power system 220 are not visible in FIGS. 2-3. More information regarding lift arm control is described in commonly owned US published patent application US 2022 / 0025607 entitled “Mechanical Self-leveling Lift Arm Structure for Power Machine,” which is hereby incorporated by reference.

[0045] FIG. 4 is a real' perspective view of frame 210 of an exemplary power machine configured as loader 200, including a first exemplary embodiment of a platform suspension assembly 300. FIG. 5 is a rear perspective view from a lower vantage point, showing structures underneath the platform suspension assembly 300. Two specific embodiments of such an assembly are described, and in some cases they will be differentiated by referring to the first embodiment with reference number 300a and the second embodiment with reference to number 300b. However, in many aspects, the assemblies are similar; descriptions of assembly 300, 300a or 300b apply to all embodiments unless otherwise specified. This convention also applies to other similarly numbered elements.

[0046] As shown in FIGS. 4, 5, 10 and 11, assembly 300 is pivotally attached to frame 210 at upper pivot joint 302 of upper arm 304 and at lower pivot joint 306 of lower arm 308. FIGS. 6 and 7 are side perspective views of two embodiments of a platform suspension assembly 300, designated as assembly 300a in FIG. 6 and assembly 300b in FIG. 7. In many respects, these assemblies are similar. Some variations in structures are illustrated, and yet others are described in the written specification. Shock absorber 310 is pivotally attached to each set of upper arms 304 and lower arms 308 on one side of platform 252. In exemplary embodiments, shock absorbers 310 connected in the four-arm structure of assembly 300 allow reciprocal vertical motion of platform 252 relative to machine frame 210, to counteract jostling as the loader 200 traverses a bumpy ground surface.

[0047] FIGS. 8 and 9 are side perspective views of a platform suspension assembly 300. Horizontal reference lines shows that upper pivot joint 302 and lower pivot joint 306 are at about the same elevation in both FIGS. 8 and 9. However, differential extension of the shock absorbers 310 allows for lowering and raising of the platform 252. Thus, the described platform suspensionassembly 300 provides not only shock absorption, but also adjustability in an elevation of the platform 252 relative to the machine frame 210 (see FIGS. 10 and 11). Referring back to FIGS. 2 and 3, it can be seen that raising an elevation of platform 252 would allow a shorter operator to have a better view of an implement attached to the front of loader 200 at implement carrier 272. An ability to raise and lower the platform 252 depending on operator height also allows for optimal positioning of operator control inputs 262 for comfort and ease of use. As shown in FIGS. 6-11, provision of a four-arm mounting assembly for platform 252, with each of the pair of arms pivotally attached to a shock absorber 310, allows the platform 252 to remain substantially level (though in some embodiments slightly inclined, as shown in FIGS. 10 and 11) throughout its operation and at any set height.

[0048] Throughout this disclosure, reference is made to arms 304, 304a, 304b, 308, 308a, 308b, and are referred to as set(s) of arms, arm, etc. All descriptions relevant to various terms that refer to an arm, arms, or set of arm(s) is inclusive to interpretations of other such terms unless indicated otherwise. As shown in FIG. 6, each arm of each set of the arms 304a, 308a can have a double plate design or, as shown in FIG. 7, each arm of the set of arms 304b, 308b can have a single plate construction. Moreover, a combination of such structures can be used in a single assembly 300. As shown in FIG. 6, platform 252a has a plurality of apertures 312 through the platform surface to decrease weight and allow for shedding of debris and water. As shown in FIG. 7, platform 252b in an exemplary embodiment has a raised surface texture 314 thereon for increased traction. An end of each of the arms of the set of arms 304, 308 that is not attached to loader 200 is pivotally attached at joint 316 to side plate 318. As shown in FIG. 7, side plate 318b is solid. In contrast, FIG. 6 shows plate 318a with aperture 320 therethrough for reduction in weight and material use.

[0049] In FIG. 6, shock absorber 310a is configured as a spring with an adjustable damper. As shown in FIG. 7, shock absorber 310b is configured as a pneumatic cylinder with an adjustable default extension setting option. While not specifically illustrated, a simple helical coil spring can also be used as a shock absorber 310. In an exemplary embodiment, shock absorber 310 has an adjustable spring rate to allow an operator to select a softer or stiffer suspension for the platform 252, considering factors such as the terrain on which loader 200 will be operated, user weight and height, and suspension preference. A suitable shock absorber 310 may be, but is not limited to, acoil-over oil dampening shock, or a pressurized gas spring, or an adjustable air dampener shock. For example, one suitable shock absorber 310a is commercially available as a Trkimal brand shock suspension spring having a size of 190 millimeters and a rating for 750 pounds. Another suitable shock absorber 310b is commercially available from DNM Performance Suspension of Taiwan as model “Air Pressure Adjustable AL7005 Shark / AL 6061 Shock.” A selection of a particular shock absorber 310 may depend on factors such as a desired stiffness of the suspension, a weight of expected operators and cost. Moreover, given a particular shock absorber 310, an effective spring rate and platform elevation can be manually adjusted by adjustment features 322 provided on the arms 304, 308. Adjustment features 322 are illustrated as discrete holes through the arms 304, 308 for the acceptance of pivot bushings at each end of each shock absorber 310. However, other structures offering attachment of shock absorber 310 at the same or different locations along the length of the arms 304, 308 can also be used, including a slider, track and ratchet system, ball screw, or clamps, for example.

[0050] While a particular number of attachment features 322 is illustrated, more or fewer can be provided on arms 304, 308. In an exemplary embodiment, attachment features 322 for upper arm 304 are located farther from upper pivot joint 302, and attachment features 322 for lower arm 308 are located relatively closer to lower pivot joint 306. Thus, shock absorber 310 is attached to arms 304, 308 at an inclination that prevents binding in the assembly 300 as the length of the shock absorber 310 changes, due to vibration attenuation, or intended change in platform height, or a combination of these effects. While one direction of inclination of shock absorbers 310 relative to arms 304, 308 and the machine frame is described, it is to be understood that an opposite direction of inclination could alternatively be used. In that case, some relationships of distances and suspension effects will be different than described.

[0051] For a given shock absorber 310 having a particular spring rate, attaching the shock absorber 310 to an adjustment feature 322 that is farther from lower pivot joint 306 results in a less stiff platform 252, allowing for more vertical displacement for a given operator weight. Conversely, moving the attachment points of a shock absorber 310 closer to the pivot joint 306 on arm 308 results in a stiffer platform 252, having less displacement for a given operator weight and travel condition.

[0052] Some shock absorbers have an integral feature for changing the absorption or spring rate of the shock absorber. For example, in an exemplary mechanical spring shock 310a, a spanner nut can be adjusted to set the spring rate at a desired level. In an exemplary pneumatic cylinder 310b, air pressure within the cylinder can be preadjusted to set the cylinder extension and spring rate at a desired level. For the pneumatic cylinder 310b, this feature can be used not only for setting the suspension and shock absorption characteristics, but also for setting a default height of the platform 252, as shown in FIGS. 8-11. FIGS. 8 and 9 have horizontal reference lines through the pivot joints 302, 306 by which the platform suspension assembly 300 is attached to a power machine 100, 200. For a given attachment location of shock absorber 310 on adjustment features 322 of upper arm 304 and lower arm 308, a shorter shock absorber 310 provides for a lower platform elevation (FIGS. 8 and 11), and a longer shock absorber 310 provides for a higher elevation of platform 252 (FIGS. 9 and 10).

[0053] FIGS. 10 and 11 are side elevation views of a platform suspension assembly 300 attached to a power machine, with the platform in relatively raised and relatively lowered positions, respectively. In an exemplary embodiment, platform 252 is slightly inclined at about 14 radial degrees from horizontal. This inclination induces an operator to lean forward toward the operator controls 262 rather than backward while standing. With the disclosed four-arm linkages for assembly 300, platform 252 remains substantially at this orientation throughout its vertical travel. Thus, the operator experiences a stable ride, even over unlevel ground surfaces, as the suspended platform travels reciprocally up and down with extension and retraction of the shock absorbers 310 to attenuate bouncing experienced by the power machine 100, 200.

[0054] While manual selection of shock absorbers 310 and adjustment is described, it is also contemplated that pneumatic lines can be installed to allow for automatic adjustment through operator control input 262 to adjust the suspension capabilities of an assembly 300 and / or the elevation of platform 252. For example, with respect to FIG. 8, an operator of shorter stature may find it more comfortable and safe to step on a lowered platform 252. Once the operator is comfortably standing on platform 252 of loader 200, the operator can activate a control input 262 to send commands through the operator control system 260 to pneumatic valves and actuators in order to extend the pneumatic cylinders 310b and thereby raise the platform 252, as shown in FIG. 9. Thus, during operation of the loader 200, the operator will have an enhanced view over themachine of the implement attached to the front implement carrier 272. More information regarding an operator control system is described in commonly owned US patent US 10,344,453 entitled “Joystick Controller for Power Machine,” which is hereby incorporated by reference.

[0055] Additionally, selection of a location of the shock absorber 310 on adjustment features 322 of arms 304, 308 affects the elevation of platform 252 for a given, unchanged length of shock absorber 310. Moving an attachment location of shock absorber 310 on adjustment features 322 so that the shock absorber 310 has a more vertical disposition will raise the elevation of platform 252. Conversely, moving the attachment point(s) of shock absorber 310 on the arms 304, 308 so that the shock absorber 310 has a more inclined orientation (away from a vertical position and toward a horizontal position) will result in lowering an elevation of platform 252.

[0056] FIGS. 12 and 13 are partial rear perspective views of a machine 100, 200 with an exemplary platform assembly 300 and an attached hip pad assembly 324 at a relatively raised elevation and at a relatively lowered elevation, respectively. FIGS. 14 and 15 are rear and front perspective views, respectively, of the exemplary platform assembly 300 and an attached hip pad assembly 324. In an exemplary embodiment, hip pad assembly 324 includes a pair of mirror-image pads 326, each attached by link 328 to the platform suspension assembly 300. In an exemplary embodiment, each pad 326 is formed from a polymer foam with a durable skin or shell or offer hip support and cushioning to an operator standing on platform 252. In an exemplary embodiment, link 328 is pivotally attached to upper arm 304 and to side plates 318 at pivot joint 316, though other connection locations on platform suspension assembly 300 and / or frame 210 could also be used. In an exemplary embodiment, link 328 in includes an arm 334 that extends substantially perpendicular to the primary orientation of link 328, to allow for the spaced attachment of fasteners 336 to different areas of pad 326.

[0057] In an exemplary embodiment, each pad 326 and / or link 328 includes one or more slider devices such as rollers 330, which are configured to travel vertically in respective slots 332 of mainframe 212 of power machine 100, 200. As shown in FIG. 12, each of the rollers 330 is at an upper portion of respective slots 332 when the platform 252 is relatively raised. In contrast, as shown in FIG. 13, each of the rollers 330 is at a lower portion of respective slots 332 when the platform 252 is relatively lowered. In an exemplary embodiment, a vertical distance between platform 252 and each hip pad 326 is maintained, as defined by a length of link 328, even aschanges in the lengths of shock absorbers 310 occur during operation. However, in other embodiments, the hip pad assembly 324 or parts thereof can be connected to the mainframe 212 independently of the platform suspension assembly 300. For example, hip pads 326 can be fixed to the mainframe 212 at set locations based on a primary operator’s height. While rollers 300 are illustrated, the attachment of pads 326 and / or links 328 to allow sliding relative to mainframe 212 could alternatively or additionally be accomplished with a set of links or other apparatuses.

[0058] Exemplary, non-limiting embodiments of an assembly and method are described. While these descriptions relate to the illustrative embodiments for ease of understanding, it is to be understood that the subject matter is not limited to these examples. In an exemplary embodiment, a platform assembly 300 is configured for attachment to a power machine 100, 200. In an exemplary embodiment, the assembly 300 comprises first and second upper arms 304, first and second lower arms 308, first and second shock absorbers 310, and a platform structure 252, 318. In an exemplary embodiment, each of the first and second upper arms 304 has a first pivot joint 302 configured for attachment to the power machine 100, 200 and an opposed second pivot joint 316. In an exemplary embodiment, each of the first and second lower arms 308 has a third pivot joint 306 configured for attachment to the power machine 100, 200 and an opposed fourth pivot joint 316. In an exemplary embodiment, the first shock absorber 310 is pivotally attached to the first upper arm 304 between its first pivot joint 302 and its second pivot joint 316. In an exemplary embodiment, the first shock absorber 310 is pivotally attached to the first lower arm 308 between its third pivot joint 306 and its fourth pivot joint 316. In an exemplary embodiment, the second shock absorber 310 is pivotally attached to the second upper arm 304 between its first pivot joint 302 and its second pivot joint 316, and is pivotally attached to the second lower arm 308 between its third pivot joint 306 and its fourth pivot joint 316. In another embodiment, each shock absorber 310 is connected to a respective lower arm 308 at third pivot joint 316. In yet another embodiment, each shock absorber 310 is connected at its lower end to the machine frame. In an exemplary embodiment, the platform structure 252, 318 is attached to the first and second upper arms 304 at the second pivot joints 316 and is attached to the first and second lower arms 308 at the fourth pivot joints 316.

[0059] In an exemplary embodiment, the platform structure comprises a platform 252 and first and second side plates 318 attached to the platform 252. In an exemplary embodiment, the firstside plate 318 is attached to the first upper arm 304 at its second pivot joint 316 and attached to the first lower arm 308 at its fourth pivot joint 316. In an exemplary embodiment, the second side plate 318 is attached to second upper arm 304 at its second pivot joint 316 and attached to the second lower arm 308 at its fourth pivot joint 316. In an exemplary embodiment as shown in FIG. 6 for example, at least one of the first or second upper arms 304a or the first or second lower arms 308a comprises two parallel plates.

[0060] In an exemplary embodiment, at least one of the first or second shock absorbers 310 comprises an adjustable spring shock 310a. In an exemplary embodiment, at least one of the first or second shock absorbers 310 comprises a pneumatic cylinder 310b. In an exemplary embodiment, the first shock absorber 310 is attached to the first upper arm 304 at a first distance from the first pivot joint 302 and attached to the first lower arm 308 at a second distance from the third pivot joint 306, wherein the first distance is greater than the second distance.

[0061] In an exemplary embodiment, the first upper arm 304 comprises a plurality of attachment features 322 along a length of the first upper arm 304, so that the first distance depends upon which of the plurality of attachment features 322 is selected for attachment of the first shock absorber 310. In an exemplary embodiment, the first lower arm 308 comprises a plurality of attachment features 322 along a length of the first lower arm 308, so that the second distance depends upon which of the plurality of attachment features 322 is selected for attachment of the first shock absorber 310.

[0062] An exemplary method of using a platform assembly 300 on a power machine 100, 200 comprises adjusting a spring rate of at least one of the first or second shock absorbers 310. In an exemplary method, at least one of the first or second shock absorbers 310 is a spring shock 310a, and adjusting the spring rate comprises turning a spanner nut on the spring shock 310a. In an exemplary method, at least one of the first or second shock absorbers 310 is a pneumatic cylinder 310b, and adjusting the spring rate comprises changing an air pressure within the pneumatic cylinder 310b. In an exemplary method, changing an air pressure within the pneumatic cylinder 310b change a length of the pneumatic cylinder 310b, thereby changing an elevation of the platform structure 252, 318 relative to the power machine 100, 200.

[0063] In an exemplary method, the first shock absorber 310 is attached to the first upper arm 304 at a first distance from the first pivot joint 302 and attached to the first lower arm 308 at asecond distance from the third pivot joint 306. In an exemplary method, adjusting the spring rate comprises changing at least one of the first distance or the second distance. In an exemplary method, the first lower arm 308 comprises a plurality of attachment features 322 along a length of the first lower arm 308, wherein changing the second distance comprises selecting a different one of the plurality of attachment features 322 for attachment of the first shock absorber 310. In an exemplary method, changing at least one of the first distance or the second distance thereby changes an elevation of the platform structure 252, 318 relative to the power machine 100, 200.

[0064] Although the subject of this disclosure has been described with reference to several embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the scope of the disclosure. In addition, any feature disclosed with respect to one embodiment may be included in another embodiment, and vice-versa. All references mentioned in this disclosure are hereby incorporated by reference.

Claims

WHAT IS CLAIMED IS:

1. A platform assembly (300) configured for attachment to a power machine (100, 200), the assembly comprising: first and second upper arms (304), each of the first and second upper arms (304) having a first pivot joint (302) configured for attachment to the power machine and an opposed second pivot joint (316); first and second lower arms (308), each of the first and second lower arms (308) having a third pivot joint (306) configured for attachment to the power machine and an opposed fourth pivot joint (316); first and second shock absorbers (310), wherein: the first shock absorber (310) is: pivotally attached to the first upper arm (304) between its first pivot joint (302) and its second pivot joint (316); and pivotally attached to the first lower arm (308) Between its third pivot joint (306) and its fourth pivot joint (316); and the second shock absorber (310) is: pivotally attached to the second upper arm (304) between its first pivot joint (302) and its second pivot joint (316); and pivotally attached to the second lower arm (308) between its third pivot joint (306) and its fourth pivot joint (316); and a platform structure attached to: the first and second upper arms (304) at the second pivot joints (316); and the first and second lower arms (308) at the fourth pivot joints (316).

2. The platform assembly (300) of claim 1, wherein the platform structure comprises: a platform (252); and first and second side plates (318) attached to the platform (252).

3. The platform assembly (300) of claim 2, wherein:the first side plate (318) is attached to the first upper arm (304) at its second pivot joint (316) and attached to the first lower arm (308) at its fourth pivot joint (316); and the second side plate (318) is attached to second upper arm (304) at its second pivot joint (316) and attached to the second lower arm (308) at its fourth pivot joint (316).

4. The platform assembly (300) of claim 1, wherein at least one of the first or second upper arms (304) or the first or second lower arms (308) comprises two parallel plates.

5. The platform assembly (300) of claim 1, wherein at least one of the first or second shock absorbers (310) comprises an adjustable spring shock.

6. The platform assembly (300) of claim 1, wherein at least one of the first or second shock absorbers (310) comprises a pneumatic cylinder.

7. The platform assembly (300) of claim 1, wherein the first shock absorber (310) is: attached to the first upper arm (304) at a first distance from the first pivot joint (302); and attached to the first lower arm (308) at a second distance from the third pivot joint (306); wherein the first distance is greater than the second distance.

8. The platform assembly (300) of claim 7, wherein the first upper arm (304) comprises a plurality of attachment features (322) along a length of the first upper arm (304), so that the first distance depends upon which of the plurality of attachment features (322) is selected for attachment of the first shock absorber (310).

9. The platform assembly (300) of claim 7, wherein the first lower arm (308) comprises a plurality of attachment features (322) along a length of the first lower arm (308), so that the second distance depends upon which of the plurality of attachment features (322) is selected for attachment of the first shock absorber (310).

10. The platform assembly (300) of claim 1, wherein the platform structure is configured to maintain an orientation relative to the power machine (100, 200) as each of the first and second upper arms (304) pivots about respective first pivot joints (302) and as each of the first and second lower arms (308) pivots about respective third pivot joints (306).

11. The platform assembly (300) of claim 1 comprising: a link (328) attached to the platform structure; and a pad (326) attached to the link (328).

12. The platform assembly (300) of claim 11, wherein the link (328) is attached to the platform structure at the second pivot joint (316).

13. The platform assembly (300) of claim 11, wherein the pad (326) is movable relative to the power machine (100, 200).

14. A method of using a platform assembly (300) on a power machine (100, 200), the platform assembly comprising: first and second upper arms (304), each of the first and second upper arms (304) having a first pivot joint (302) configured for attachment to the power machine and an opposed second pivot joint (316); first and second lower arms (308), each of the first and second lower arms (308) having a third pivot joint (306) configured for attachment to the power machine and an opposed fourth pivot joint (316); first and second shock absorbers (310), wherein: the first shock absorber (310) is: pivotally attached to the first upper arm (304) between its first pivot joint (302) and its second pivot joint (316); and pivotally attached to the first lower arm (308) between its third pivot joint (306) and its fourth pivot joint (316); and the second shock absorber (310) is:pivotally attached to the second upper arm (304) between its first pivot joint (302) and its second pivot joint (316); and pivotally attached to the second lower arm (308) between its third pivot joint (306) and its fourth pivot joint (316); and a platform structure attached to: the first and second upper arms (304) at the second pivot joints (316); and the first and second lower arms (308) at the fourth pivot joints (316); the method comprising adjusting a spring rate of at least one of the first or second shock absorbers (310).

15. The method of claim 14, wherein the at least one of the first or second shock absorbers (310) is a spring shock, and wherein adjusting the spring rate comprises turning a spanner nut on the spring shock.

16. The method of claim 14, wherein the at least one of the first or second shock absorbers (310) is a pneumatic cylinder, and wherein adjusting the spring rate comprises changing an air pressure within the pneumatic cylinder.

17. The method of claim 16, wherein changing an air pressure within the pneumatic cylinder changes a length of the pneumatic cylinder, thereby changing an elevation of the platform structure relative to the power machine.

18. The method of claim 14, wherein the first shock absorber (310) is: attached to the first upper arm (304) at a first distance from the first pivot joint (302); and attached to the first lower arm (308) at a second distance from the third pivot joint (306); wherein adjusting the spring rate comprises changing at least one of the first distance or the second distance.

19. The method of claim 18, wherein the first lower arm (308) comprises a plurality of attachment features (322) along a length of the first lower ami (308), wherein changing the seconddistance comprises selecting a different one of the plurality of attachment features (322) for attachment of the first shock absorber (310).

20. The method of claim 18, wherein changing at least one of the first distance or the second distance thereby changes an elevation of the platform structure relative to the power machine (100, 200).

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