Patent Application
20240026636
The present invention is directed to grading apparatus for vehicles. These typically comprise an adjustable mouldboard and are used for levelling and grading operations. Included is apparatus capable of attachment to existing and smaller vehicles. Embodiments allowing roll, yaw, and sideshifting adjustment are discussed. Improved slope sensing arrangements for increased grading accuracy are also discussed.
The applicant has produced levelling systems for attachment to vehicles such as skid steer loaders and excavators. These types of box levelling systems are very good for precision levelling and contouring of work sites, often comprising large areas.
However, there is still a need in the industry for a grader type system—particularly for road, pavement, and similar types of work even though the box type levelers can be used in such applications if required. At the moment options are limited, and tend to be a scaled down version of a convention full-sized grader's gooseneck arrangement for attachment to a vehicle.
A problem with the arrangement of conventional graders is that they are designed for fast work rather than precision work. Typically the forward support arm of a grader is a gooseneck arrangement which pulls the blade body portion forwardly. Effectively the cab and engine are at the rear, and the mouldboard is pulled forwardly behind the front wheeled assembly. This means the main load (from the blade of the mould board assembly grading against material) is at a point near the front of the gooseneck. Forward drive from the engine has to be transmitted down the gooseneck to this connection point—which puts a considerable amount of load and stress on the gooseneck support assembly. If the mould board blade hits an embedded rock or obstruction then damage can occur.
These factors also affect the design of the gooseneck portion, which tends to be heavy, and strong to resist typical forces (but not necessarily the occasional untypical situation). This also affects maneuverability, and the requirement for a large vehicle to drive it. Such design considerations also make it difficult to do precision work and typical graders may have 10 mm or so of flex or slop at the mould board edge due to the gooseneck system.
Hence, in work sites (which are typically of a smaller scale than major roading) we have a few issues associated with the prior art:
These associated issues have precluded grader attachments to be fitted to smaller vehicles, or for performing the precision work required on most worksites currently. Also, because operators will want to use them like they do a typically blade leveller or bulldozer blade, designs based on current grader designs are not sufficiently rugged. Often this may include lifting broken seal and pavement as part of grading the sub course—this is not advisable nor recommended on existing grader designs.
Further, when working with grading equipment additional considerations arise, as often larger amounts of material on the ground are shifted. As part of this type of application consideration needs to be given to ensuring that excess material is moved outwardly of the path of the track of the vehicle on which apparatus is mounted—else wise the track or wheel vehicle will encounter an aggregate row and operations will be adversely affected.
When the accessory, such as a blade, is in a transverse orientation excess material will typically pushed outside of the path of the vehicle wheels or tracks. However, if the blade or accessory is angled about a vertical axis, the outer ends of the accessory come within the path of the wheels/tracks. It would be advantageous if the accessory could be offset or sideshifted to clear at least one of the left and right wheel/track paths.
Hence it would be useful to have an improved sideshift arrangement suitable for various mounted accessories, particularly those in which the orientation of the mounted accessory can change.
It would be similarly useful to have an improved side shift design which bore a reduced forward/reverse load component during operation of apparatus.
In practice it would be useful to have an improved grader design suitable for small vehicles as well as large. There is a need in the industry to have smaller grading apparatus rather than relying on large traditional gooseneck graders. Also, as many businesses have significant investments in vehicles (such as skid steer loaders and the like) capable of connecting different accessories, there is demand for a suitable grader attachment—particularly if it is capable of precision work.
Hence it would be useful to have an improved grader design suitable for high precision levelling and grading work.
Similarly it would be useful to have a grader assembly capable of working under reasonably high load conditions without any flexing or deformation of components affecting the precision of a grading operation.
Further, it would be useful in the art to have a grader assembly capable of both forward and reverse operation with a similar degree of precision, and ideally also without significantly reconfiguring components.
It would also be useful to have an improved grader design which would be more durable in respect of the manner in which many operators may wish to use it.
It is an object of the present invention to address at least some of the above problems.
At the very least it is an object of the present invention to provide the public with a useful alternative choice.
Aspects of the present invention will be described by way of example only and with reference to the ensuing description.
A general overview of the invention follows:
According to one aspect of the present invention there is provided a grader assembly for use on a vehicle, said grader assembly comprising:
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which there is present a vertical planar arrangement of two said primary load links situated such that one is substantially one above the other.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which said arrangement of two primary load links lie substantially in a vertically plane, and each have pivotable connections at each end to the respective body portions they connect to.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which each of the two primary load links of the arrangement connect, when viewed in plan, to the main body portion close to its middle.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which there is present a triangular arrangement of two said primary load links which, when viewed in plan, extend outwardly from their pivotable connection point to either the main body portion or blade body portion so as to pivotably connect to the alternate body portion outwardly of its middle (also when viewed in plan).
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which said two primary load links of the triangular arrangement lie substantially within a horizontal plane when the lower edge of the blade portion is parallel to horizontal ground.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, which includes at least one additional primary load link located, when viewed from the side, either or both above and below the plane of said triangular arrangement of two primary load links, and which pivotably connect to a point lying on the vertical rotational z-axis of the blade body portion.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which a primary load link is a fixed length linkage.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which there is at least one adjustable yaw controlling linkage extending between the main body portion and blade body portion, whose adjustment in length effects rotation of the blade body portion about its vertical rotational z-axis.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which a said adjustable yaw controlling linkage lies outwardly, when viewed in plan, of a saggital vertical plane intersecting the blade body portion's vertical rotational z-axis.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which there is a forward extending mounting point associated with the main body portion, and wherein there is present at least one adjustable roll controlling linkage connected to said forward extending mounting point and extending outwardly therefrom when viewed in plan to a connection point on the blade body portion.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which a said adjustable roll controlling linkage lies substantially within a vertical plane passing through the blade body portion.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which there are a pair of adjustable roll controlling linkages, one disposed either side of their connections to said forward extending mounting portion.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, which includes at least one adjustable side-shift controlling linkage which connects to the blade body portion on or near its vertical rotational z-axis, and at its alternate end to the main body portion at a point outwardly of a vertical saggital plane passing through said vertical rotational z-axis.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which an adjustable controlling linkage comprises an actuator.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which a fixed linkage comprises a link whose length is not adjustable during use.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which a fixed linkage is substituted by an adjustable length linkage.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which the bottom edge of the blade body portion comprises any one or more of: a levelling blade, dual levelling blades for bidirectional levelling, a rotary powered accessory, a brush, and a rake.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which a feature on the bottom edge of the blade body portion can be replaced or substituted.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which the main body portion includes a forwardly extending mounting arm, and there is also provided at the forward end of the arm a wheeled carriage assembly.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which said forwardly extending mounting arm is adjustable in length.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which the forward extending mounting point is located on said forwardly extending mounting arm.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which the main body portion includes a quick hitch mounting arrangement to a vehicle.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, including a stabilised slope sensor assembly comprising a sensor portion, and sensor mounting portion;
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which said sensor portion is a slope sensor oriented, when viewed from above, substantially along a transverse axis and is restricted in position within the coronal plane during either or both roll and yaw adjustments of the blade body portion relative to the main body portion.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which the sensor mounting portion comprises an arm extending between the main body portion and blade body portion, said arm falling substantially within or parallel to the sagittal plane of the grader assembly.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, including a sensor guidance system providing spatial information to either or both a vehicle operator, and a control system for operating adjustable linkages of the grader assembly.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which a said sensor guidance system comprises one or more of a proprietary: 2D guidance system, 2.5D guidance system, 3D guidance system, ultrasonic guide system, laser guidance system, visual recognition guidance system.
According to another aspect of the present invention there is provided a grader assembly, substantially as described above, in which on either or both ends of the blade body portion there is provided a pivoting wing extension, pivotable about a substantially vertical axis.
According to a further aspect of the present invention there is provided a grader assembly, substantially as described above, attached to a vehicle.
Various aspects and embodiments of the invention will now be generally described, though it is appropriate to define a few terms used with the specification. This is particularly true due to the variable geometries that components may attain during use.
A vehicle to which the invention may be attached is broad. While developed for smaller skid-steer loader type vehicles, smaller and larger vehicles may be considered. This includes tracked vehicles, semi-tracked vehicles, various tractors and bulldozers, excavators, etc.
Typically embodiments of the present invention will be mounted on the front of a vehicle, at the end the driver faces. For the purposes of simplicity of description, the description herein shall assume this to be the case—particularly when describing directions and geometries. However this does not preclude embodiments of the present invention being fitted to the rear of a vehicle.
Referencing the front mounted arrangement for describing the invention, the longitudinal axis shall lie substantially along the middle of the vehicle/grader when viewed from above and shall be the normal forward/reverse direction for the vehicle with any steering wheels pointed straight ahead. This may also be referred to as the x-axis.
Transverse, when viewed from above, shall be perpendicular to the longitudinal axis. This may also be referred to as the y-axis.
The ground plane, which is a typical reference plane for the description herein, shall be considered horizontal when used as a reference in this description. This is an xy plane with no z-axis component.
The z-axis shall be a vertical axis, perpendicular to the ground xy plane.
With reference also to
A pivotable joint may take many known forms. Typically it shall be a joint or connection which allows at least some angular movement between the connected components. This may be about substantially a single axis, or about multiple axes. It may include joints with bearings, spherical bushes, and other known types of pivotable joints/connections. Quite commonly embodiments of the present invention may use components of, or similar to, the automotive industry as steering and suspension components typically require pivotable joints. As, in the automotive industry, links with pivotable end joints are readily available in a range of sizes and strengths, theses can often be used off the shelf in various embodiments of the present invention.
There are several different aspects of the invention which, for simplicity, shall be referred to one at a time. The simplest form is a grader assembly in which the blade portion is capable of angular yaw movements only (similar to a typical grader). However most operations also require elevation control, and ideally also roll angle control. Hence, the first main embodiment shall describe embodiments having yaw, elevation and roll control though it should be envisaged that the elevation and roll control elements can be eliminated if these movements are not required, or a simpler vertical adjustable linkage substituted for dual adjustable linkages if only elevation, and not angular roll control, is required. Hence the more fully featured embodiments will be described as they give a deeper understanding to the operation and philosophy of the invention.
In s second improved form, an option to sideshift the blade portion is provided. While not always required, there are situations where this option is desirable or necessary. Hence the second part of the description shall describe the side-shifting options which are closely related in construction to the non-sideshifting embodiments above.
In a third portion, discussion will be made of an improved slope sensing arrangement. Due to the multiple geometries of a grader blade according to the present invention, existing slope sensors fitted to the blade portion give inaccurate readings. Where an operator, or a control system, is relying on accurate readings/indications (for accuracy and precision in grading operations), existing prior art arrangements will not work. This section discusses a potential solution to such issues.
Discussion—General Non-Sideshifting Grader Assembly
As a summary of these types of embodiments:
According to this aspect of the present invention there is provided a grader assembly comprising a main body portion, said main body portion with a forward support portion in turn supporting a forward wheeled assembly;
In another aspect there is a grader assembly in which there is at least one load support linkage from a point (or points) on said blade body portion to said main body portion.
In another aspect there is a grader assembly in which a said load support linkage is connected to said blade body portion, when viewed in plan, near the middle thereof.
In another aspect there is a grader assembly in which a said load support linkage is connected to said main body portion at a point outwardly, when viewed in plan, of the middle thereof.
In another aspect there is a grader assembly in which there are two said load support linkages which, when viewed in plan and with said blade body portion aligned substantially with a transverse axis of the grader assembly, are substantially in mirror symmetry with respect to the sagittal plane of the apparatus.
In another aspect there is a grader assembly in which said load support linkages are either fixed in length, or adjustable in length.
In another aspect there is a grader assembly in which at least one end of a said load support linkage comprises a connection comprising a flexible bush, a ball joint, other pivotable joint, or the like.
In another aspect there is a grader assembly in which said load support linkage connections accommodate aforesaid permitted arcuate movement of said blade body portion.
In another aspect there is a grader assembly in which there is provided at least one auxiliary support linkage between a point (or points) on said blade body portion and main body portion.
In another aspect there is a grader assembly in which a said load auxiliary linkage is connected to said blade body portion, when viewed in plan, near the middle thereof.
In another aspect there is a grader assembly in which a said auxiliary support linkage is connected to said main body portion at a point outwardly, when viewed in plan, of the middle thereof.
In another aspect there is a grader assembly in which there are two said auxiliary support linkages which, when viewed in plan and with said blade body portion aligned substantially with a transverse axis of the grader assembly, are substantially in mirror symmetry with respect to the sagittal plane of the apparatus.
In another aspect there is a grader assembly in which said auxiliary support linkages are either fixed in length, or adjustable in length.
In another aspect there is a grader assembly in which at least one end of a said auxiliary support linkage comprises a connection comprising a flexible bush, a ball joint, other pivotable joint, or the like.
In another aspect there is a grader assembly in which said auxiliary support linkage connections accommodate aforesaid permitted arcuate movement of said blade body portion.
In another aspect there is a grader assembly in which, when viewed from the side, the connection point of a said load auxiliary linkage to said blade body portion is at a different elevation to the connection point of a load support linkage.
In another aspect there is a grader assembly in which, when viewed from the side, the connection point of a said load auxiliary linkage to said main body portion is at a different elevation to the connection point of a load support linkage.
In another aspect there is a grader assembly in which there is provided at least one mould board arc controlling linkage between said main body portion and blade body portion, said linkage being adjustable in length and wherein adjustment of said length alters, when viewed in plan, the angle of the blade body portion relative to the sagittal plane of the a grader assembly.
In another aspect there is a grader assembly in which a said mould board arc controlling linkage comprises an actuator
In another aspect there is a grader assembly in which said actuator is any one or more of hydraulic, pneumatic, or electrical in operation.
In another aspect there is a grader assembly in which there are at least a pair of arc controlling linkages.
In another aspect there is a grader assembly in which a said pair of arc controlling linkages are, when viewed in plan and the blade body portion in a transverse position, substantially in mirror symmetry with the sagittal plane of said grader assembly.
In another aspect there is a grader assembly in which said support arm portion is telescoping in length.
In another aspect there is a grader assembly in which actuators are provided to adjust said length of said support arm portion.
In another aspect there is a grader assembly in which there are one or more angled bracing elements or assemblies between said forward support arm portion and the main body portion, the arrangement to help maintain, when viewed in plan, a substantially perpendicular relationship between the main body portion and the forward support arm portion.
In another aspect there is a grader assembly in which there is provided at least one roll limiting linkage between said blade body portion and forward support arm portion.
According to another aspect of the invention there is provided a grader assembly in which a said roll limiting linkage is adjustable in length.
In another aspect there is a grader assembly in which an adjustable roll limiting linkage comprises an actuator.
In another aspect there is a grader assembly in which length adjustment of a roll limiting linkage allows for adjustment of the roll angle of said blade body portion, said roll angle being substantially about an axis perpendicular to the transverse coronal plane of said blade body portion.
In another aspect there is a grader assembly in which there are at least a pair of roll limiting linkages.
In another aspect there is a grader assembly in which a said pair of roll limiting linkages are, when viewed in plan and the blade body portion in a transverse position, substantially in mirror symmetry with the sagittal plane of said grader assembly.
In another aspect there is a grader assembly in which a roll limiting linkage, when the grader assembly is viewed in plan, is connected to said forward support arm portion at, or near, a point directly above a connection between either of both of that of an auxiliary support linkage and the blade body portion, and that of a load support linkage to said blade body portion.
In another aspect there is a grader assembly in which there are at least two roll limiting linkages.
In another aspect there is a grader assembly in which said blade body portion comprises a blade portion.
In another aspect there is a grader assembly in which a lower edge of said blade portion comprises a hinged lower edge portion along its lower edge, the arrangement allowing upward pivoting from a limited lowered position.
In another aspect there is a grader assembly in which said pivoting arrangement of the lower edge portion limits rearward pivoting movement same, while allowing forward pivoting movement.
In another aspect there is a grader assembly in which the pivoting arrangement is such that during forward movement of said grader assembly rearward pivoting of said lower edge portion is limited to allow for a grading operation, while during reverse travel of said grader assembly said lower edge portion can pivot forwardly upwardly to allow material to pass underneath.
In another aspect there is a grader assembly in which there is provided at least one side-wing portion at either or both ends of said blade body portion.
In another aspect there is a grader assembly in which a said side wing portion is pivotably connected to said blade body portion.
In another aspect there is a grader assembly in which a said side portion is, when viewed in plan, pivotable within an arc substantially within the transverse plane of the grader assembly.
In another aspect there is a grader assembly in which there is provided wing angle means to, when viewed in plan, control the angle of a side wing portion relative to the blade body portion.
In another aspect there is a grader assembly in which the arrangement between a said side wing portion and said blade body portion is such to allow a said side wing portion to attain a position substantially parallel to the sagittal plane of said a grader assembly during the permitted range of arcuate (yaw) movement of said blade body portion.
In another aspect there is a grader assembly wherein said main body portion is adapted to be attached to a vehicle.
In another aspect there is a grader assembly wherein a proprietary quick mount mechanism is provided to allow attachment of the main body portion to a vehicle.
In another aspect there is a grader assembly wherein said grader assembly is substantially permanently affixed to a vehicle.
Preferred embodiments of this type of the present invention comprise grader assembly attachable to a vehicle—typically (but not necessarily) using a proprietary or ubiquitous quick hitch or connect arrangement. It also envisaged that designs of the present invention may be more permanently attached to a vehicle.
One distinguishing feature of preferred embodiments of this aspect of the present invention is that most of the load on the blade of the blade body portion is transmitted more directly to the vehicle, and typically to the mounting portion of the main body portion which directly attaches to load bearing points on the vehicle. This is in contrast to existing grader designs where the load of the blade is transmitted to the forward gooseneck support arm, which then has to transmit the load back to the driving vehicle. In preferred embodiments the forward support arm primarily supports the forward wheeled portion (which rests on the ground and provides little longitudinal resistance/load) as well as being a point from which linkages to control any permitted yaw and roll movements of the mouldboard are mounted. Most of the load, in preferred embodiments, transmit the bulk of operational load (from forward grading operation) to the main body portion through load support and auxiliary support linkages. In preferred embodiments reverse grading is also possible and the same linkages, which typically have a reasonably high tensile strength, are equally capable of transmitting loads between the main body portion (in the vicinity of the vehicle mounting point) and the blade body portion. Hence high load transfer in both directions along a longitudinal axis can be catered for.
Through such more direct linkages between the blade body portion and main body portion (directly affixed/attached to the vehicle) any movement or slop can be minimised compared to existing grader designs. A range of ball joint, flexible bush, and pivotable connection options may be chosen and employed, which allow necessary movement (blade body portion relative to main body portion) while maintaining tight connections and tolerances required for precision grading operations. Multiple linkages can further assist in the transfer of load and minimising any introduction of movement or flexing at joints or in linkages—even if the apparatus is used atypically for a conventional grader.
In preferred embodiments, viewed from the side, there are upper and lower sets of load support and auxiliary support linkages to transmit load from the blade body portion to main body portion. These linkages tend to be of fixed length, but may be of adjustable length in alternative embodiments.
The upper and lower sets, viewed from the side, may cross paths with lower connection points ascending to higher connection points at the distal end of the linkage, and vice versa.
Viewed from above the various linkages may be arranged substantially in mirror symmetry about the sagittal axis of the grader assembly. Various combinations may be employed in specific alternative embodiments.
Limited arcuate movement of the mouldboard representing a yaw movement is typically provided in preferred embodiments. Adjustable linkage(s) between the mould board and main body portions are typically provided in the form of an actuator. In a preferred embodiment a pair of actuators, substantially in mirror symmetry relative to the sagittal plane when viewed from above, are provided though other geometries can be considered.
Roll arcuate movement of the mouldboard portion can be provided on various embodiments. In a preferred embodiment to be described later a pair of roll limiting linkages comprising actuators, again substantially in mirror symmetry to the sagittal plane when viewed from above, is provided. These are also substantially aligned above the blade body portion, which will be quite apparent in the drawings. It should be noted that other and varying geometries may be employed other than the preferred embodiment discussed later.
Typically also, the roll limiting linkages could raise and lower the blade body portion (and hence blade lower edge) if provided in a matching mirror pair as previously mentioned—hence raising/lowering and roll adjustments can be made.
Load transmission has been previously discussed, and while the linkage arrangements discussed above will typically allow for adequate load transmission in both directions of operation, in some situations it is desirable for the apparatus to grade in one direction only. Hence, in some preferred embodiments of the present invention the lower edge of the blade of the blade body portion has a hinged lower edge portion which typically rests against stops or other features to prevent rotation during operation of the grader assembly in one direction (typically forward) while being able to freely pivot upwardly during grading operations in the opposite direction. On work sites it is often necessary for equipment to work in tight spaces or confines, often having to reverse backwards to completing a grading operation in several forward movements. This is not typically an issue in standard road construction where road sections under repair are usually quite long and unobstructed.
In preferred embodiments pivoting side wing portions are also provided. When grading loose aggregate (for example) a ridge of loose material can form at the edges of a blade, and more so at a trailing end. Typically some of this ridge (depending on height) will flow back behind the outer end of the blade. This can be a problem if it falls within the track of the vehicle, where wheels/tracks can run over this material and compromise the integrity of the finished graded area. With adjustable pivoting side wings the formed ridges can be pushed further clear of the ends of the blades to that they are clear of the vehicle track path. While not so much of a problem when the blade body portion is substantially transverse, at maximum yaw adjustment the ends of the blade may be close to, or within, the track path of the supporting vehicle. The side wings can be used to push the ridge of loose aggregate outwardly of the vehicle track path. However, in normal usage they are not intended to grade (as does the main blade) and need not be of as heavy construction. Also, a single (or multiple) actuator can be used to control its position, which may also be linked to the yaw angle of the blade body portion or as the operator desires.
The forward wheel assembly may take different forms as required, but typically rest on the ground to help stabilise the assembly.
Raising and lowering of the blade of the blade body portion can be accomplished if desired by different means. One such method is fine to medium adjustments through simultaneous operation of the roll limiting linkages, though this may not be readily achievable near maximum permitted roll movement of the blade body portion.
Raising and lowering the main body portion (to which the main body portion of the grader assembly is affixed) of the vehicle can also be used to adjust relative blade body portion height.
In some embodiments an additional actuator or actuators may be employed to effect mould board height.
Suitable receivers, transceivers, reflectors, emitters etc. may be mounted on grader assembly of the present invention to interact with various site levelling/contouring systems such as GPS, laser, 2D, 3D systems etc. These can be interfaced with actuator control circuitry to effect the necessary adjustments of the mouldboard and blade edge as the supporting vehicle moves across a work site.
The nature and operation of the embodiment described above will be better described with reference to the drawings later herein.
Typically standard hydraulic pumps, valves, and control circuits will be used for the control of the various actuators of hydraulic embodiments of the present invention herein. Typically there is a control array system (60) of such components which communicate actions from a user on control devices or levers to the various actuators. These may be configured to allow one user action to simultaneously act on a plurality of actuators to perform a desired action. Such arrangements are well known in the art and provide a degree of user choice. In more sophisticated arrangements information from guidance systems may automatically control actuators—often making changes until the components of the grader assembly attain the correct attitude, position, orientation etc. Again, coupling existing equipment to guidance systems is well known in the art, and commonly provided by proprietary guidance systems. However this does not preclude the advanced skilled reader from implementing their own user choices in the control of the embodiments of the present invention described throughout herein.
Various communication means may also be used to convey operating instructions from a driver/user to a control system or actuators etc. These include physical wired (electrical, optical, etc) systems though given the harsh working environments wireless arrangements may be more practical—e.g. WiFi, Bluetooth, various other wireless transmission protocols etc. It is also an option, as an addition or substitute for typical standard control levers, that a wireless tablet or device may be provided. This may be fixed in a vehicle cab, though may be removable. This latter option would allow controls to be easily transported to different vehicles when the grader apparatus was attached to a different vehicle—a useful option on a large site, large company, or equipment rental situation. It could also allow an operator to control the grading apparatus from outside the cab of the vehicle if need be. Configuring controls into an app/software for standard phones and tablets is an envisaged control option.
Discussion—Side-Shifting Grader Assembly
According to one aspect of the present invention there is provided a sideshifting grader assembly comprising at least a main body portion and an blade body portion coupled to each other;
In another aspect there is a sideshifting grade assembly in which the main body portion of said sideshifting grade assembly is able to be mounted to a vehicle.
In another aspect there is a sideshifting grade assembly in which during typical operation the sideshifting grade assembly is intended to operate primarily in a longitudinal direction.
In another aspect there is a sideshifting grade assembly in which when mounted to a vehicle said longitudinal direction corresponds to forward and reverse movement of said vehicle.
In another aspect there is a sideshifting grade assembly in which when mounted to an excavator type arm, said longitudinal direction corresponds to the longitudinal axis of the arm when viewed in plan from above.
In another aspect there is provided a sideshifting grader assembly, substantially as described above, in which said sideshifting grade assembly comprises an accessory.
In another aspect there is a sideshifting grade assembly in which said accessory comprises one or more of: a blade, a mouldboard, a rotary ground modifying accessory, a rake.
In another aspect there is a sideshifting grade assembly in which the long axis of said accessory is at an angle to said longitudinal direction.
In another aspect there is a sideshifting grade assembly in which the long axis of said accessory when viewed in plan is substantially perpendicular to said longitudinal direction.
In another aspect there is a sideshifting grade assembly in which said sideshifting grade assembly enables rotation of said accessory within a range of angles relative to the transverse direction when viewed in plan.
In another aspect there is a sideshifting grade assembly in which said range of angles relative to the transverse direction fall within 45 degrees on the transverse direction when viewed in plan.
In another aspect there is a sideshifting grade assembly in which the restricted relative movement between said first translation portion and said blade body portion is such that linear motion between the two substantially in the direction of allowed translational movement between said first and second translation portions is one of controlled, limited, or prevented.
In another aspect there is a sideshifting grade assembly in which there is a fixed substantially immovable connection between said first translation portion and said blade body portion.
In another aspect there is a sideshifting grade assembly in which the relationship between said second translation portion and said main body portion is such that is such that linear motion between the two substantially in the direction of allowed translational movement between said first and second translation portions is one of controlled, limited, or prevented.
In another aspect there is a sideshifting grade assembly in which there is at least one sideways stabilising link between said second translation portion and said main body portion which restricts relative lateral sideways movement between the two.
In another aspect there is a sideshifting grade assembly in which a said sideways stabilizing link is a fixed length linkage.
In another aspect there is a sideshifting grade assembly in which a said sideways stabilizing link is connected to either or both said second translation portion and said main body portion by a pivoting connection.
In another aspect there is a sideshifting grade assembly in which said pivoting connection is a universal joint.
In another aspect there is a sideshifting grade assembly in which linkages between mount and blade body portions bear load from operation.
In another aspect there is a sideshifting grade assembly in which there is a plurality of substantially fixed length linkages.
In another aspect there is a sideshifting grade assembly in which roll adjusting actuators do not significantly contribute to longitudinal load bearing forces during operation.
While the primary portion of the invention described herein relates to a means of allowing translational sideshift movement of an accessory in a ground working/sideshifting grade assembly (while the ground is the typical workface, various embodiments may be used on other workfaces) the description takes on more relevance for the skilled reader when applied to actual equipment. Hence the use of three embodiments in the description herein, though it is noted that these and other embodiments employing the translational sideshift arrangement herein are novel and inventive in their own right as well as by virtue of the translational sideshift arrangement.
In many embodiments of the present invention the blade body portion is able to be moved into a number of different configurations. For simplicity we shall assume the accessory is a mouldboard with a blade and that it is positioned level and aligned in the transverse direction when viewed from above. We shall assume, as mentioned above, that the sideshifting grade assembly is a grader assembly. In this arrangement sideshift ability typically means translational movement of the accessory in the transverse direction. If the accessory (when viewed from above) is aligned along an axis angled to the transverse direction, then a “side shift” translational movement shall be regarded as aligned along this axis. Similarly, if viewed from the front the accessory is aligned to a slope axis which is angled to the transverse axis, then a “side shift” translational movement shall be regarded as aligned along this slope axis. In simpler terms, the “side shift” translational axis is typically aligned with the long axis of the accessory. Hence, “side shift” typical means the blade body portion can shift sideways in a coordinate system fixed relative to the accessory (and not to other components of the sideshifting grade assembly etc.).
Accordingly there is ideally a first translation portion fixed or associated with the blade body portion which includes (or to which may be mounted) the accessory. Where the first translational portion goes, the blade body portion follows.
Associated with the first translation portion is a second translation portion. This is fixed, mounted, integrated or otherwise coupled with the main body portion of the sideshifting grade assembly such that its movement relative thereto is limited. The relationship is such that a predominantly or solely translational movement between the two translation portions are possible. Now if we take the “rest situation” where the accessory is largely orientated in the transverse and level position described above, the permitted translational movement between the two translation portions will be substantially aligned and parallel with the transverse y-axis. In preferred embodiments relative movement in other directions is limited or otherwise constrained.
This relative translational movement may be achieved in a number or ways. It could be accomplished by a cylinder/actuator which is able to power this translational movement as well. It could also be accomplished by a shaft within a cylinder, which is the preference in preferred embodiments for reasons of simplicity, strength and durability—but need not be limited to this arrangement. Various track and other mechanical arrangements are known to provide relative translational movements and may be employed.
As part of the consideration in the present invention is the fact that cylinders/actuators are provided for movement of the blade body portion within a coronal plane (if the accessory is aligned when viewed from above with the transverse y-plane). If a non-powered sliding translational mechanism is used (as opposed to an actuator or the like) the blade body portion can self adjust as the roll inducing actuators (i.e. roll relating to movement within yz coronal plane in a reference rest configuration). Depending on the geometry of the one or more roll influencing actuators, some adjustment of the two translational portions is typically required due to changing of the overall geometry. If an actuator is used for the side-shift translational mechanism, the control system would need to calculate and make small adjustments which adds to the complexity of the control system and cost. If such an actuator is locked into a fixed length position then changes in geometry would need to be taken up elsewhere and unexpected or unwanted geometry changes elsewhere may occur. Hence the preferred embodiments employ a freely sliding (and consequently self-adjusting) translational mechanism.
The use of a freely sliding shaft within an outer tube is less expensive and enables larger diameter/rated components to be employed without significant cost increases. Larger durable bushes to prevent the ingress of particulate or foreign matter are readily available for shaft in tube/guide arrangements. Similarly internal bearings for use in such arrangements are readily available. Based on current availability and costs of components, the current use of a shaft in guide translational mechanism is a good choice even if not the only choice.
It is important to note that the relationship between the second translation portion and the main body portion is not totally fixed or immovable. Because the accessory (and typically blade body portion) of the sideshifting grade assembly is often movement about various rotational axes relative to the main body portion, these additional movements to side shifting need to be accommodated. Hence in many preferred embodiments there is a link arrangement between the second translation portion and main body portion which employs universal or other pivoting type joints. The primary role (in an assembly in the notional rest position) of the second translation portion in combination with the main body portion is to prevent or limit sideways movement of the second translation portion along the transverse direction. Accordingly the second translation portion essentially becomes a fixed extension of the main body portion and a reference point to which the first translation portion (and associated blade body portion) may translate sideways (in the notional rest position) relative to. The permitted geometry changes of the second translation portion relative to the main body portion (i.e. other than sideways) allows other orientations of the blade body portion (e.g. roll and yaw) to be followed and accommodated without components breaking off or the overall geometry locking itself into an immovable configuration.
In preferred embodiments, particularly the described nominal grader assembly, a forward extension bar extends from the main body portion and is a useful point for attaching a stabilising element such as a link between the second translational portion and the main body portion. In preferred embodiments this essentially comprises a panhard rod/link and as mentioned previously ideally has a universal connection at either or both ends. This represents a relatively simply solution relatively impervious to many of the aggressive environments that many embodiments of the present invention may be used.
In most embodiments of the present invention there is a plurality of linkages (be it fixed and/or adjustable (e.g. actuators) between the accessory/blade body portion and the main body portion. The primary role of these is to maintain and/or effect the adoption of the accessory/blade body portion into different configurations (e.g. with components of one or more of roll, pitch, and yaw). Various arrangements may be employed in different embodiments depending on the requirements of the final assembly. These arrangements are documented in the art, including in previous published patents and applications of the present inventor—these describe the general mechanisms to the notional skilled reader though additional considerations may come into play in the present invention.
Apart from enabling different configurations of the blade body portion (from henceforth this will include accessory unless otherwise stated) these linkages (fixed and otherwise) help bear the load (typically in a longitudinal x-axis) on the blade body portion—translating it back to the main body portion which is typically securely mounted to a vehicle at a point engineered to take such loads. Various arrangements and geometries may be employed in different embodiments of the present invention.
A side-shift effecting arrangement (in simple terms a single actuator) may be mounted between points on the mount and blade body portions. Typically, when viewed from above in plan view, and with the assembly in the notional rest configuration, one or both mounting points of the side-shift actuator will be displaced outwardly of the longitudinal centreline (x-axis) of the assembly. Multiple actuators may be employed. Other arrangements to effect controlled relative translational movement of the blade body portion relative to the main body portion may also be employed.
Some of the linkages between the accessory and main body portions may effect roll movement of the blade body portion (relative to the main body portion). In preferred embodiments described later herein, the roll controlling actuators/mechanism are substantially isolated from x-axis loads bearing on the blade body portion during operation of the assembly. Accordingly these actuator components are mounted substantially overhead relative to the blade body portion—the forward main body portion extending from the main body portion is a convenient place. This largely reduces the x-axis load component from the roll controlling mechanism/portion. This can aid the durability of components, reduce potential stress, and allow lower-rated components to be employed. In grading operations there is relatively little y or z axis loading and thus overhead style mounting can help restrict loads to those occurring in the y and z axes. However the loadings may be different for other non-grading embodiments used in different situations. Potentially realizable advantages of overhead arrangements is that actuator and moving components can be elevated further above aggregate or other workface materials during operation, thereby reducing potential intrusion of foreign matter.
Comparing the sideshifting embodiments to the non-shifting embodiments described above, there is often a difference in the fixed length load-bearing linkages—i.e. the primary load links. As for the non-sideshifting embodiments primary load links extending from the main body portion ideally connect to a vertical rotational z-axis of the blade body portion (and which axis is typically near the middle of the blade body portion). Thus rotation of the blade body portion about this z-axis is possible for angular yaw rotation in both types of design.
However, preferred non-sideshifting embodiments of the present invention may include a triangular arrangement of two diverging primary load links—spreading outwardly from the saggital plane as they approach the main body portion. This arrangement, where present (and non-sideshifting embodiments may use the vertically disposed primary load links of the sideshifting embodiments) prevent sideways translational movement of the blade body portion relative to the main body portion. This is addressed by having multiple primary load links positioned to lie substantially within the sagittal plane—avoiding the triangular (when viewed from above) link arrangement. Another arrangement is to make one or both links in a triangular arrangement adjustable. In fact in preferred embodiments there is an additional adjustable link which, in combination with the central primary load links, forms a triangular arrangement when viewed from above. This adjustable link is actually an adjustable side-shift controlling linkage (and there can be a pair on either side of the saggital plane). This triangular arrangement also helps improve stability when the blade body assembly is in different side shifted positions. Connecting the end attached to the blade body portion close to the vertical rotational z-axis can help secure any bracing effect as well as not interfering with angular yaw movement of the blade body portion (else it could end up opposing yaw controlling adjustable links).
It should be appreciated that pivoting wing portions at the end/ends of the blade body portion can be implemented on both sideshifting and non-shifting embodiments of the present invention.
The nature and operation of the embodiment described above will be better described with reference to the drawings later herein.
Discussion—Slope Sensor Arrangements
This part of the present invention is directed more to equipment where the blade (e.g. ground modifying element or portion) is capable of cross-fall (roll in aviation terms or angling about the apparatus's longitudinal axis (typically the direction of travel)) as well as yaw (rotation about a vertical axis perpendicular to the ground. In typical levellers, such as the applicant has previously produced, there is no yaw component—in fact it is typically prevented. However grader systems, such as the present invention, introduce yaw so that the blade or accessory is capable of attitudinal changes in three dimensions rather than the two dimensions of typical box type levellers. While placing a slope sensor on top of the blade body portion gave accurate readings (ignoring slow response times for rapid blade roll changes), this does not work when three dimensions are involved—which will be discussed more fully herein.
In the art it is often desirable to measure the cross-fall (roll angle) to determine the angle of the blade. The typical solution is to provide a slope sensor mounted to the blade/accessory portion. Apart from poor response times, and susceptibility to vibration, of many slope sensors on the market it typically represents a good solution. The information is typically usable for control and guidance systems enabling an operator (or automated control system) to maintain the required fall/slope on a site that is being worked.
However, issues arise when a blade/accessory capable of yaw adjustment (sometimes known as blade rotation). Here measuring the cross-fall with a slope sensor runs into problems and as the blade is rotated (yaw) the actual cross-fall as applied to the surface being worked changes. Instead of an even surface of constant slope we end up with an uneven surface of varying slopes corresponding to every time the rotational yaw angle of the blade was changed.
Where a 2D, 2.5D, or 3D sensor system is being used with elevated sensors near the outer ends of the blade the problem is often eliminated—the control and guidance systems automatically adjust the blade to maintain a constant cross-fall across the area being worked. However, often simpler solutions are used on some sites. As an illustrative example, it is not uncommon for a string line to be used as a guideline on a site—e.g. along the edge of a path, road, carpark etc. A sensor, such as an ultrasonic sensor (or otherwise) detects and uses the string line as a reference line. The cross-fall is constant so all the operator/control system typically has to do is maintain the correct elevation of the blade as the apparatus moves forward (or in reverse). If the rotational yaw angle of the blade remains the same then we have no problem.
However if we alter the rotational yaw angle we have a major problem. The effective cross-fall being machined into the ground changes. So if, for instance, the blade has a measured slope of 3° and is being used perpendicular (viewed in plan, or 0° rotational yaw angle from standard) we get a slope of 3° machined into the ground. However with a rotational yaw angle of, say, 45° we might get a machined slope of 5° into the ground—depending on the specific geometry of the machine.
This can be visualised if the same blade at 3° slope is able to rotate 360° on the machine. If we rotate it such, the result is not a planar machined incline of 3° but a conical indentation in the ground. If one measures the slope on the indentation along various lines perpendicular to our string line, it will be noted the effective machined slope at different points on the cone are different.
So there is the problem—for a constant slope on the blade, the act of blade rotation (yaw) changes the effective cross-fall (measured perpendicular to the string line when viewed in plan) machined into the ground. Hence the actual slope of the blade at various yaw orientations needs to be adjusted to maintain a constant cross-fall measured across a specific angle (typically perpendicular) to our reference (string or other) line.
Some have proposed automated systems which try to vary the blade's slope in relation to yaw rotation. There are issues with such arrangements which often also suffer issues in the field. One issue is that it can increase the complexity of a simple sensor/reference system. This can add to cost and introduce reliability issues. A more important issue stem from issues associated with slope sensors which, as previously mentioned, can be relatively slow to respond and are not resistant to vibration. What can happen is the control system makes an adjustment based on a slope value and other calculations. Due to multiple actuators often being used, we can end up in a feedback loop of adjusting one actuator to respond causes a geometry change which another actuator tries to respond to (to correct the system). This subsequently causes another geometry change which the first actuator tries to correct. Add more actuators which can influence geometry if they are altered, and also lag times and jittery information from slope sensors, and the system can go into a cross-coupling or feedback loop of constant correction. And add further to this that the whole apparatus may be moving across uneven ground. All of this cross-coupling adjustments can significantly affect the quality of the finish that the apparatus is capable of.
Accordingly there is a real need in the art for an alternative solution to address the aforementioned issues.
In another aspect there is sensor stabilising apparatus for use on the accessory portion of ground modifying equipment (such as though not restricted to a grader assembly) comprising:
In another aspect there is sensor stabilising apparatus in which the accessory portion is a mouldboard or body portion on which an accessory is mounted.
In another aspect there is sensor stabilising apparatus in which the accessory is a blade.
In another aspect there is sensor stabilising apparatus in which the sensor portion includes a sensor
In another aspect there is sensor stabilising apparatus in which the sensor associated with the sensor portion is a slope sensor
In another aspect there is sensor stabilising apparatus in which the sensor is orientated to be at a specific angle relative to the longitudinal axis of the apparatus to which it is to be attached, when viewed in plan.
In another aspect there is sensor stabilising apparatus in which said specific angle is perpendicular to the longitudinal axis when viewed in plan.
In another aspect there is sensor stabilising apparatus in which there is provision for adjusting said specific angle.
In another aspect there is sensor stabilising apparatus in which the first mounting portion is adapted to attached to said accessory portion at a position on, or close to, the vertical pivot axis about which said accessory portion rotates during a rotational yaw adjustment.
In another aspect there is sensor stabilising apparatus in which said first mounting portion includes pivot means allowing relative rotation of said sensor apparatus to said accessory portion.
In another aspect there is sensor stabilising apparatus in which said relative rotation of said sensor apparatus to said accessory portion is about a substantially vertical axis.
In another aspect there is sensor stabilising apparatus in which said second mounting portion is adapted to allow connection to a point on said ground modifying equipment which does not experience yaw rotation during rotational yaw adjustment of said accessory portion.
In another aspect there is sensor stabilising apparatus in which at least one of said mounting portions are adapted to attach to a link portion, or component associated therewith on said ground modifying equipment.
According to a further aspect of the present invention there is provided a method of installing a slope sensor to provide slope readings at a specific angle relative to a reference line, and/or the direction of travel of ground modifying equipment, said method comprising:
According to yet a further aspect of the present invention there is provided ground modifying equipment fitted with sensor stabilising apparatus substantially as described above.
According to yet another aspect of the present invention there is provided ground modifying equipment including a sensor mounted according to a method substantially as described above.
In another aspect there is ground modifying equipment with a sensor which comprises one or more of: a grader, a grade attachment, a ground levelling vehicle, a ground levelling attachment, and a ground working attachment.
In the present invention one of the things we are generally trying to achieve is to be able to determine the effective cross-fall being effected on the ground by the blade or accessory. Generally this is in relation to the horizontal at a specific angle (viewed in plan). Typically this angle is perpendicular to the direction of normal forward (or reverse) travel of the ground working equipment when viewed from above. This may also be regarded as being perpendicular to a nominal reference line when the ground working equipment is travelling parallel thereto. We shall for the purpose of explanation herein refer to the horizontal line at this specific angle as the reference zero cross-fall line and which is parallel to our nominal unworked ground surface. We shall refer to the effective accessory cross-fall angle as the measured angle relative to this reference zero cross-fall line when viewed along a direction parallel to the ground (and which is also perpendicular to the zero cross-fall line when viewed from above—which for simplicity is also parallel to the direction of travel).
In the above situation and parameters (reference zero cross-fall line is perpendicular to the direction of travel when viewed from above), the effective accessory cross-fall angle is the angle of cross-fall that is formed into the ground when measured relative to the reference zero cross-fall line.
In practice, if the roll angle of the accessory remains unaltered while the rotational yaw angle is changed then two things happens (providing the roll angle is not zero):
This discrepancy occurs for reasons mentioned previously, because the slope sensor is only measuring a component of the effective accessory cross-fall angle and not the effective accessory cross-fall angle itself. The issues of a wrong slope reading have been mentioned above.
In simple terms the present invention seeks to remove errors in the measurement by directly measuring the full component of the effective accessory cross-fall angle—i.e. a reading gathered with a sensor substantially aligned to the true cross fall measuring direction rather than at an angle thereto.
For simplicity of description this will be discussed in more detail with reference to the drawings, due to the difficult to visualize geometries involved.
The following description in relation to the accompanying drawings is given by way of example only, and not intended to be limiting. These serve to illustrate various aspects of the invention and the best known methods of implementing the invention according to the applicant and inventor at the date of this document.
With reference to the drawings, and by way of example only, there is provided grading apparatus (generally indicated by 1) comprising a main body portion (2) and a forward support portion (3). The rear of the main body portion (3) comprises a standard quick-hitch attachment configuration (4) for attachment to a vehicle with a Quick Hitch attachment mechanism. Other types of attachment arrangements may be used in various embodiments.
In this case the tracks (5) of a vehicle (not shown) are illustrated to give an idea of scale and position. A vehicle need not be tracked, and tracks (5) are shown for illustrative purposes only.
Also shown is a section of ground (6) as a reference base, and also shown are the wheel/track (5) paths (7) for a linearly travelling vehicle. Again this gives a sense of scale and position for the preferred embodiment (1) illustrated.
A blade body portion (8) includes a blade (9) with (in this embodiment) dual pivoting lower edge portions (10). Only one is visible in this figure, though the opposing element on the other side of the blade (9) is visible in following figures. The hinged arrangement (11) associated with edge of the hinged edges (10) allow the trailing edge portion (10) to pivot upwardly while stops (not visible) limit travel of the leading edge portion (10). This dual arrangement allows for grading in both directions such that only the leading edge portion (10) effectively grades the ground (6).
Side wings (12) pivot about a vertical axis, and are controlled by an arm arrangement (14) and actuator (not visible in this figure). While these wings can extend the reach of the blade for ‘soft’ grading applications, their main intended purpose is to stop a ridge of graded aggregate material from sloping back into the wheel/track path (7). The wings can be used to keep such aggregate materials well clear of the wheel paths (7).
In this embodiment a pair of fixed length load support linkages (15) are provided. These connect (16) near the middle of the blade body portion (8) when viewed in plan by a pivotable connection, typically comprises a resilient bush (such as a truck suspension bush) or ball joint or similar, The connection point (16) tends to act as the pivot point for yaw movement of the mould board assembly, which will become more evident in the following drawings. In this arrangement they have mirror symmetry about the sagittal plane when viewed in plan.
A single auxiliary linkage (17) of fixed length is provided above (in this embodiment) the load support linkages, and follows (when viewed in plan) a substantially longitudinal central path. It is noted that more than one auxiliary linkage can be provided. A pair of auxiliary linkage could be provided, and these may also have mirror symmetry about the sagittal plane when viewed in plan.
These load support and auxiliary linkages transfer most of the load from the blade body portion (8) directly back to the main body portion (2) and to the vehicle through the integral hitch arrangement (4). This direct load transferences and suitable pivotable joints allow for quite a rigid system under both forward and reverse load during operation. This reduction in flexing helps provide higher precision grading apparatus than standard grading arrangements, potentially realising a factor of 5-10 times greater in blade edge precision thereover.
Yaw rotation of the blade body portion (8) is achieved by mould board arc controlling linkages (18) comprising actuators. Relative lengthening and shortening can provide the required/desired degree of yaw. The following drawings will illustrate the relationship in lengthening and shortening the actuators (18) for different mould board yaw positions. Yaw in this context relates to an arc within the transverse xy plane, or rotation about an axis perpendicular thereto. In this embodiment there are a pair of linkages (18) having, when viewed in plan, mirror symmetry about the sagittal plane.
Roll control of the blade body portion (8) is achieved by roll limiting linkages (19) also comprising actuators. These connect with pivotable type mounts (bushes, ball joints, etc) to a point (20) on the forward support portion (3) and extend to points (21) outwardly of the middle of the blade body portion (8). In this arrangement there are a pair of roll limiting linkages which, when viewed in plan, are distributed in mirror symmetry about the sagittal axis of the apparatus (when the mould board is oriented transversely).
The roll control linkages (19) can be independently shortened and lengthened to adjust the roll orientation of the mould board (8). However it is noted that simultaneous shortening or lengthening of the pair of linkages (19) by the same amount can raise and lower the blade body portion while maintaining the current roll orientation. Hence this allows for both roll and elevational control of the blade body portion (8).
At the forward end of the forward support portion (3) is a wheel carriage portion (23) which may be of differing design though a simple preferred arrangement is illustrated here. A telescoping arm section (51) allows the carriage portion to be adjusted forwardly or rearwardly relative to the main body portion (2).
Vertical support posts (26) may be provided for mounting sensors/transceivers/components etc of varying guidance and control systems which may be employed. These systems may interact with control systems for actuators (18,19) associated with the grading system to alter the height and roll orientation of the blade body portion (8) as the attitude of the vehicle and grading apparatus alters as it travels across the ground. Mention of guidance systems have been made elsewhere herein.
Following are a number of views of the same embodiment of
Additionally the vertical axis (130) is ideally located lie on the longitudinal (sagittal) plane of the apparatus (1) (when in the rest position). Offsetting this axis from the central plane adds complications in geometry and may introduce additional stresses if other components of the apparatus are not repositioned to compensate. Typically, it is currently more desirable to have an embodiment where operations can be equivalently mirrored left and right rather than restricted or biased to a particular side.
In alternative embodiments a four link system could be used, where the upper link (17) is substituted by two links—either in a parallel (when viewed from above), or triangular arrangement like the lower links (15), or another orientation. In practical terms however, these options likely provide minimal advantage in relation to their additional complexity. Some such arrangements can place additional stress on the mouldboard and connection points as it attains different orientations. Further, the region in the vicinity is relatively crowded and it can be difficult to include additional links without there being interference between components during operation.
Of some consideration is that the lower links (15) provide a relative stable triangle which helps prevent unwanted sideways movement of the mouldboard (8) relative to the main body portion (2) during operation. While a panhard rod or other mechanical equivalents could be employed to help prevent unwanted lateral movement, we come back to complexity issues and trying to position components so that they don't interfere with each other during operation of the invention. The options are possible in various embodiments, though the illustrated version represents, at this time, the best practice implementation of the inventor.
The connections (16, 31, 32) represents pivoting joints, typically allowing at least 5° nominal pivoting from normal, and ideally 10°. Some connections such as those on the mouldboard may require a greater degree (e.g. 15-20°) of freedom depending on the specifics of the implemented embodiment. Heavy duty flexible bushes (41) with end caps (40), and allowing a large pin (42) or bolt to pass through the centre of the end of the link are typically preferred. Other than being relatively inexpensive and available —commonly used in truck suspension systems—they are relatively resistant to the ingress of particulate matter as may occur during use of the invention. The ability to easily fasten or bolt (43) the centre pin (42) can be an advantage during construction and maintenance. For connections with higher degrees of operating angular freedom, a double cup shield (such as seen in
The geometry of the links (15, 17) and their flexible connections (16, 31, 32) allow the mouldboard portion (8) to go up and down relative to the main body portion (2). If the upper (17) and lower (15) links are maintained to be substantially parallel to each other when viewed from the side then the mouldboard can rise and fall without any significant change in pitch—generally a desirable outcome. While other geometries may be employed, most grading operations prefer not to have changes in pitch as height/elevation is altered—it adds additional complexity for the operator and/or any control system present.
The yaw controlling actuators (18) have similar pivotable connections (e.g. 39R) at each end as well to allow for changes in geometry. In the preferred embodiment they are typically, when viewed from the side, substantially parallel to the links (15, 17) though (as for the former) there may be geometry variations to avoid contact between components during operation. The fixed length links (15, 17)—which could be actuators or variable links in various embodiments—typically bear the force of a load on the mouldboard and ideally during forward and reverse operation. It is foreseeable that the top single link (17) could be substituted by an actuator to enable mouldboard pitch changes in alternative embodiments.
The upper roll control actuators (19) also typically have the same type of pivotable connections at their connection points (20, 21). These actuators (19) are positioned above the mouldboard (8) in the illustrated embodiment, partly as it frees up the crowded area between the mouldboard (8) and main body portion (2). Positioning the actuators to substantially lie within the roll plane (which the mouldboard rotates through) allows a greater portion of the actuators force to be translated to a roll movement—in an alternative embodiment where the actuator instead spans between the mouldboard (8) and main body portion (2) only a partial component of the actuators force may contribute to a pure lifting or raising action.
Ideally also, the actuators' (19) central connection (20) is aligned with vertical axis (130) see (
The positioning in the preferred embodiment as illustrated also means that the same two actuators (19) can easily be used for mouldboard height/elevation adjustment (simultaneous operation by the same amount) as well as roll variation. This can make it easier for an operator under manual control or control systems, as opposed to some other geometries.
In practice also, having the actuators span a wide lateral distance between the centre of the mouldboard (viewed in plan) an its outer ends can allow for better fine control as a specific change in length of the actuator will have a smaller effect on angle than if the outer end was connected to the mouldboard nearer its centre. Hence we can potentially realise more accurate control (and cater for tolerances in the precision of the actuator's operation). The arrangement can have an advantage in addressing cross coupling (where an adjustment on one side prompts an adjustment on the other side to compensate for any movement there, and where that second adjustment then re-prompts a further adjustment on the other side ad infinitum). Better fine control can help reduce cross-coupling issues in the field.
Also of consideration is how grading and levelling systems are used. Typically if one alters the roll angle, you do not want the resulting action to be a pivot about the centre connection point (20) as typically this will cause one outer end of the blade (10) of the mouldboard (8) to dig into the ground while the other end will raise above it (more of a problem during manual operator control). In practice you want one end (typically the reference end, lower end, or end the operator prefers) to remain at the same elevation while changing the roll angle alters the height at the other end. This helps the operator/apparatus create a quality finish as opposed to a scalloped finish.
Effectively the change in roll angle is about the outer connection point (21). As this is near the outside end of the mouldboard (8) we only get a small change in blade (10) elevation to the outside of this point (21) while the main change in elevation due roll angle change is on the alternate side of the mouldboard (towards the middle and other side). In practice this can provide operators with better control and accuracy during operation of the apparatus.
Typically a control system and/or guidance system may be provided to assist the operator. As mentioned previously sensors, which may be on raised poles as per common in the industry, may interact with various positioning systems (e.g. ultrasonic, 2D, 2.5D, 3D systems etc). These typically either provide information to help guide manual or semiautomatic operation, or may be linked to a control system which controls actuators to make the apparatus (1) attain the required geometry as dictated by the guidance system. Various available systems typically added to equipment may be employed.
As can be appreciated, other mechanical arrangements and geometries may be adopted in various embodiments, though the illustrated embodiment is currently the best practice implementation of the inventor. This process did involve considerations of reliability, manufacturing cost, design simplification, durability in intended environments (which also includes a consideration of keeping actuators as far as possible above the ground to avoid particulate matter being graded), etc. This does not preclude further refinements or variations of the invention over time, or lesser embodiments.
In the illustrated preferred embodiment there is also a rear blade (60). Like the front blade (10) it is also hinged like the front blade (61). This means reverse operation is also possible with the trailing blade pivoting out of the way, while the leading blade rests against stops or has its rearward pivoting otherwise limited.
This can provide an advantage to an operator as they can see the rear blade (60). Quite often grading operations are done in reverse for fine control, even on conventional graders.
As another point of distinction with conventional graders, in reverse operation in the present invention is being pulled from a low point (linkages 15) whereas the mouldboard on a grader in reverse operation is being pushed from a high point. In practice, for the grader, if the blade (during reverse operation) encounters an obstruction it can dig into the ground causing the front end of the grader to pitch up and dig the blade in even further. If this happens several times in succession you can get a very corrugated and uneven finish. Pulling the blade (in reverse operation of the present invention) avoids the geometry and loadings that causes the blade to pitch and buck upon hitting an obstruction, thereby also addressing a known issue in the prior art.
The figures also illustrate the open framework nature of preferred embodiments of the present invention. In many ways this is desirable as the cabs of many smaller vehicles are lower to the ground (than convention graders) and the open structure significantly improves visibility for operators using the grading apparatus.
As previously mentioned the optional side wings may be used as needed or desired by an operator. Referring to
With reference to the drawings, and by way of example only, there is provided a sideshifting grade assembly (generally indicated by (101)) comprising at least a main body portion (102) and an blade body portion (103) coupled to each other; said sideshifting grade assembly (101) also including a sideshift assembly (generally indicated by (104), wherein said sideshift assembly (104) comprises:
Described differently the preferred embodiment of a sideshifting grader assembly comprises
In the embodiment of
In the embodiment of
The closest end of the shaft (106) in
The coupling (108) also connects the left roll actuator (114) by means of a ball or spherical bush or joint. The alternate end of the actuator (114) is coupled (typically by a similar joint type) to a mounting plate (122) on the forward arm extension (112).
Referring to
The blade body portion (103) and attachments are also supported by the shaft (106) by virtue of the relationship between the first and second translation portions (105, 106).
Two fixed length primary load links (125, 126) are distributed spaced vertically apart on the central saggital xz plane of the apparatus. A ball joint or bush or such like at each end allows a certain degree of pivotal movement with their connection to the mount (102) and accessory (103) portions respectively (such as to allow roll movement of the blade body portion (103)). These maintain the blade body portion (103), at its middle, a fixed distance from the main body portion (102). They connect to the blade body portion (103) in an aligned manner with the vertical rotational z-axis (130, 180). Ideally they lie in a single vertical plane in the illustrated embodiment—i.e. their pivotable connections to the main body portion (102) lie also on a vertical axis. This allows unrestricted sideways movement of the blade body portion (103) relative to the main body portion, noting that other provided linkages control their relative disposition. It also causes less crowding of components in this more complicated arrangement, than with triangular link arrangements such as found in non-sideshifting embodiments.
One such linkage is sideshift controlling actuator (128), also with a ball joint or bush or other pivoting connection at each end, that extends between the blade body portion (103) and main body portion (102)—which may be directly thereto or from a forward extending mount ahead of the main plane thereof (such as in the position shown in
Yaw motion of the blade body portion (103) is achieved by yaw actuator (130) positioned outwardly of the central sagittal plane and extending between the mount (102) and blade body portions (103). It tends to be substantially aligned with the longitudinal x-axis of the apparatus, so as to minimise any sideways contribution to positioning of the blade body portion (103) when it operates, though noting that various attainable geometries will take it away from being truly parallel to the longitudinal axis—particularly when there is side-shifting. Hence connections of the yaw controlling adjustable length link need to be sufficiently pivotable to accommodate the normal range of movements.
A front wheeled carriage portion (132) provides forward ground support and may be connected to the forward arm extension (112) by a telescoping arrangement.
In
Compared to the embodiment of
Compared to the embodiment of
As can be appreciated there are a number of differing geometries and combinations of actuators which may be employed on different embodiments, It is anticipated that the skilled reader of the art will appreciate these variations based on the description herein, though the description is limited largely to the best methods of implementation of the invention currently considered by the inventor.
Not shown, but typically implemented on embodiments of the present invention are sensors which may be used with conventional positional, contouring, and levelling systems. These are well known and will not be discussed in detail other than to note that such sensors typically work in conjunction with a control system to alter and/or control the orientation of the accessory during operation, though manual operator operation is still an option. There are a range of systems currently employed and adapted to be fitted to various levelling, grading, and construction machinery—typically as such systems are manufactured independently of those who make the construction machinery. GPS, laser, ultrasonic and combination systems are among those currently used, and may be 2D, 2.5D, 3D or other in operation.
In the industry these guidance systems allow high precision to be achieved, though that is largely dependent also on the accuracy and tolerances of the equipment. As mentioned earlier herein, the inventions of the present invention have been designed with such precision (compared to normal graders) in mind. As well as the information provided by guidance systems, some sensor information is often also gathered by the machinery. For instance, a guidance system might tell you the precise site position of each end of a blade portion but may struggle with elevation—though laser systems are often good at this. Regardless, knowing the roll angle of a blade is often necessary to know, especially for providing to the integrated control systems associated with the guidance system which control the attitudinal conformation of a blade. When the blade is capable of 3-dimensional movement, issues arise.
More Accurate Yaw Independent Slope Sensing
Here line (201) represents the reference zero cross-fall line, which is also parallel to the ground plane. Line (202) illustrates a particular roll angle for the accessory (for simplicity we shall assume the accessory is a blade) that has been chosen and locked into position for this demonstration. The blade has zero yaw angle when viewed from above, such as line (204) in
However, as the yaw angle of the blade is adjusted, such as to align with line (206) in
As the prior art solutions have been complex and of varying degrees of reliability and effectiveness, the current invention has evolved by stepping back and rethinking a solution rather than improving on previous solutions—a step sideways, so to speak, from the direction of the art.
In simple terms the present invention seeks a means to measure the effective cross-fall angle rather than the accessory/blade angle. Referring to
However there is also more to the solutions proposed by the present invention. The sensor mounting/sensor still needs to respond to changes in roll angle. One could say we are trying to measure the roll angle but after taking yaw angle contributions out of the equation, so to speak. Hence any mounting system still needs to be coupled to the blade so that its angle/slope changes as the roll angle of the blade changes.
In the preferred embodiment below a first mount of the sensor system attaches to the blade (or more specifically the accessory mounting portion) in a manner in which it is fixed (with respect to rotation) relative to the blade in terms of roll movements, but is also able to pivot relative to the blade in terms of yaw movement. Hence, the first mounting assembly should allow the sensor/sensor mount to tilt in response to roll movements of the blade but be allowed to pivot in response to yaw movements of the blade. This allows the sensor/sensor mount to be subsequently fixed such that it remains aligned with reference lines (205, 207) when viewed from above in figure (23) —if it is aligned with other reference lines (for some user purpose) then the reality is that it will remain substantially therewith despite yaw movements of the blade.
A second mount to a suitable point (which does not experience yaw changes) on the ground modifying equipment helps maintain this alignment. In practice, the amount by which the sensor/sensor mount angles from the horizontal reference line (201) during roll and yaw changes of the blade, will remain substantially close to the true effective cross-fall angle—i.e. the angle returned will be the measurement for the angle of line (203) rather than remaining at that for line (202) as per the case of standard mounted slope sensors.
A variety of fixed linkages and actuators connect the accessory mounting portion (212) and main body portion (216). The exact arrangement is not important (and varies in practice on different equipment) other than to say that roll and yaw angular movements of the accessory mounting portion (212) relative to the main body portion (216) are possible. The main body portion (216) is typically fixed or mounted to a vehicle so is our reference portion in terms of direction of travel etc.
In this embodiment of ground working equipment there is a central link (220) largely aligned with the direction of travel of the ground modifying equipment. A flexible bush/ball joint (221) connects the link (220) to the accessory mounting portion (212) at its middle (223). A pin (224) travels through the centre of the joint (221) as is fixedly attached to the mount (223) on the accessory mounting portion (212). The angle of this pin from true vertical changes as the roll angle of the accessory mounting portion (212) changes.
Attached to the pin is first mounting means (225) which includes pivots (226) allowing pivoting of the bracket (228) about the central axis of the pin (224). This is fixed to the sensor mounting bracket (230) on which a suitable sensor (231) is mounted.
Extending from this bracket (230) is an arm (233) which attaches to a bracket (234) attached to the main body portion (216). This arrangement keeps the arm aligned to be substantially parallel to the direction of travel, and subsequently also the sensor (231) regardless of changes in the yaw angle of the accessory mounting portion (212). A flexible pivoting connection (235) helps accommodate changes in the roll angle of the sensor bracket (230) in response to yaw and attitudinal changes of the accessory mounting portion.
Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the spirit or scope of the present invention as described herein.
It should also be understood that the term “comprise” where used herein is not to be considered to be used in a limiting sense. Accordingly, ‘comprise’ does not represent nor define an exclusive set of items, but includes the possibility of other components and items being added to the list.
This specification is also based on the understanding of the inventor regarding the prior art. The prior art description should not be regarded as being authoritative disclosure on the true state of the prior art but rather as referencing considerations brought to the mind and attention of the inventor when developing this invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 771572 | Dec 2020 | NZ | national |
| 776194 | May 2021 | NZ | national |
| 777227 | Jun 2021 | NZ | national |
| 777299 | Jun 2021 | NZ | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2021/062147 | 12/22/2021 | WO |
