WO2022225724A1

WO2022225724A1 - Corn ear aligner

Info

Publication number: WO2022225724A1
Application number: PCT/US2022/023965
Authority: WO
Inventors: Thobias AMPESSAN; Theodoro Silva ROGERIO; Osmar JUNIOR
Original assignee: Syngenta Crop Protection Ag
Priority date: 2021-04-20
Filing date: 2022-04-08
Publication date: 2022-10-27
Also published as: BR112023021756A2; AR125698A1

Abstract

Methods and apparatus are provided for increases the performance of dehusking operations while maintaining or reducing seed losses associated with the corn dehusking process. A pressure plate system is coupled to dehusking equipment to align corn ears as they travel over dehusking rollers. The biasing force applied on the corn ears by the pressure plates reduces ear drift and the need to rework corn ears.

Description

CORN EAR ALIGNER

FIELD OF THE INVENTION

The present invention relates to methods and apparatus for increasing dehusking performance while maintaining (or reducing) seed loss from corn ears during husk removal.

RELATED APPLICATIONS

This application claims priority to US Provisional Patent Application No. 63/176,967 filed 20 April 2021, the contents of which are incorporated by reference herein in their entirety.

BACKGROUND

Corn processing and seed harvesting includes a dehusking step wherein the husk is removed from green ears of corn. Dehusking is a very physical and mechanical step and is one of the main processes inside a corn processing unit. Typically, it involves corn ears being directed towards dehusking rollers via a conveyor mechanism. However, dehusking involves a significant amount of rework (varying from 30% to 70%) due to drifting of corns ears as they are processed along the conveyor mechanism. Dehusking also incurs significant seed losses (varying from 10% to 30%) due to the need to rework the material. In addition, seed losses can occur due to corn ears getting trapped or swallowed in the conveyor mechanism. Therefore, it is desirable to increase the dehusking performance with a reduction of the rework and if possible, a reduction in seed losses involved in the dehusking step.

SUMMARY OF THE INVENTION

The presently disclosed subject matter provides an apparatus that increases the dehusking performance with a maintenance (or reduction) of seed losses associated with corn dehusking process and methods of using such an apparatus during dehusking. Accordingly, the present invention is directed to a corn dehusking apparatus and system, and methods of dehusking using the same, wherein a pressure plate defines a travel path channel for corn ears moving over dehusking rollers of a conveyor mechanism in a dehusking process of a corn seed processing unit. The pressure plate(s) biases the corn ears moving on the conveyor mechanism, increasing contact with dehusking rollers. As a result, the corn ears can be aligned along the travel path channel, creating a laminar flow which reduces the likelihood of corn migration and entrapment between channels. Further, the increased contact between the dehusking rollers and the corn ears increases the likelihood of dehusking events as the corn ears are conveyed. In some embodiments, a plate assembly including a plurality of such pressure plates may be fitted (e.g., retrofitted) to conventional dehusking equipment to improve the dehusking efficiency and maintain or reduce seed losses in the processing plant. This summary lists several embodiments of the presently disclosed subject matter, and in many cases lists variations of these embodiments.

In one exemplary embodiment, a corn dehusking apparatus or dehusking system is provided for dehusking an ear of corn, the corn ear having a length L and a diameter D. In such an embodiment, the apparatus or system comprises a conveyor mechanism with at least one pair of rollers forming a travel path having an inlet end and an outlet end, wherein the travel path has a length at least 4L (e.g., at least 5L, 10L, 15L, 16L, 17L, 18L, 19L, or 20L) from the inlet end to the outlet end, and wherein the at least one pair of rollers include a dehusking surface. In some embodiments, the dehusking surface includes parallel channels, and has a coefficient of friction that is sufficient to grab the husk of a corn ear in contact with the rollers and dehusk the ear by drawing the grabbed husk across the dehusking surface.

The system further comprises a mounting shaft coupled to the conveyor mechanism. The mounting shaft can be positioned above the pair of rollers at a height in the range of 2D to 10D, or may be positioned within an inner volume of the conveyor mechanism. The system further comprises a pressure plate having a connector region, a terminal end, and a plate region there between, wherein the pressure plate is connected at its connector region to the mounting shaft, and wherein the pressure plate defines a travel path channel (TPC) between its terminal end and the at least one pair of rollers, the TPC having a height in the range of 0.9D to 2D (dependent will tighten it up a bit) and configured to allow the ear of corn to pass therethrough with a small amount of pressure. The pressure plate may have a length in the range of 2L to 4L and a width in the range of 1L to 2L. The pair of rollers may have a surface having a coefficient of friction (CoF) =X (e.g., between 0.10 and 0.50), while the plate region of the pressure plate has a CoF less than X (e.g., between 0.1 and 0.10). In some embodiments, the pressure plate is curved. In some embodiments, the system further includes a second pressure plate arranged parallel to the first pressure plate along a common travel path. Further, the second pressure plate may be distanced relative to the first pressure plate to provide an imbricated configuration relative to the first pressure plate. In such embodiments, a stopping element coupled to a given pressure plate at the connector region is configured to limit downward motion of the pressure plate, thereby averting contact between the terminal end of the pressure plate and an underlying dehusking roller. In some embodiments, the stopping element may also limit upward motion of the pressure limit to avert contact between the terminal end of the pressure plate and an overlying pressure plate of the imbricated set. In some embodiments, a plurality of pressure plates are coupled to a common mounting shaft and are distributed along a length of the mounting shaft, in adjacent travel paths.

Another exemplary embodiment of an apparatus or system for aligning corn ears comprises a conveyor mechanism with groups of rollers forming multiple travel paths for conveying ears of corn from an inlet end to an outlet end; a frame assembly coupled to the conveyor mechanism comprising a chassis having opposing side walls and opposing end walls, a plurality of longitudinal frame elements interposed between the opposing end walls, each longitudinal frame element comprising a plurality of evenly-spaced openings along a length of the longitudinal frame element; and a plate assembly comprising an array of lateral shafts engaged to longitudinal frame elements via the openings, each lateral shaft of the array supporting a plurality of curved pressure plates extending from the shaft at an angle to bias corn ears onto the travel paths. In some embodiments, the frame assembly is mounted above the conveyor mechanism.

In other embodiments, the frame assembly is fastened within a volume of the conveyor mechanism. In some embodiments, the rollers are obliquely-arranged rollers, wherein each group of obliquely-arranged rollers includes non-planar rollers, wherein the multiple travel paths are parallel travel paths divided into groups of travel paths by the plurality of longitudinal frame elements interposed between the opposing end walls, and wherein each travel path is a cradled travel path. In some embodiments, the chassis is substantially quadrangular. Each lateral element extends between a pair of adjacent longitudinal frame elements and is rotatable about a shaft axis perpendicular to a longitudinal axis of the longitudinal frame elements. A plurality of equally spaced pressure plates are engaged to each lateral element with the opposing side walls of the chassis arranged parallel to the inlet end and the opposing end walls arranged parallel to the outlet end. Each pressure plate comprises a connection region pivotably engaging the pressure plate to a corresponding lateral element, and a plate region extending from the connection region, the plate region having a terminal rectangular cut-out. In some embodiments, the connection region is made of a first material and the plate region is made of a second, different material less rigid than the first material. In alternate embodiments, the first and second materials have different CoF relative to the roller surfaces. In some embodiments, the terminal rectangular cut-out extends from an end of the plate region towards the connection region and is configured to accommodate therein a corn ear being conveyed on an underlying travel path. The connection region may comprise a stopping element on an underside of the pressure plate, the stopping element configured to maintain a separation between the plate region and an uppermost of the group of obliquely arranged rollers. The array of lateral elements may include a first set of parallel lateral elements, each lateral element of the first set extending between a first pair of adjacent longitudinal frame elements, and a second set of parallel lateral elements, each lateral element of the second set extending between a second, different pair of adjacent longitudinal frame elements, and wherein the first set of parallel lateral elements is aligned with a first travel path and the second set of parallel lateral elements is aligned with a second travel path. In some embodiments, the first pair and the second pair have a common longitudinal frame element. In further embodiments, the first set of lateral elements in the array are staggered relative to the second set of lateral elements. In other embodiments, the first set of lateral elements in the array are aligned (laterally or longitudinally) relative to the second set of lateral elements. A separation between adjacent lateral elements of the first or second set of lateral elements may be configured to be less than a length of one pressure plate.

In still another exemplary embodiment, a corn alignment system or apparatus couplable to a corn dehusking device comprises a frame assembly couplable to a periphery of the dehusking device, the frame assembly comprising a quadrangular chassis having opposing side walls and opposing end walls, a plurality of longitudinal frame elements interposed between the opposing end walls, wherein each longitudinal frame element comprising a plurality of evenly-spaced openings along a length of the longitudinal frame element, and wherein adjacent longitudinal frame elements are separated by an integral number of parallel conveyor lanes of the underlying dehusking device; and a plate assembly comprising an array of parallel lateral shafts, each lateral shaft of the array comprising opposing shaft ends rotatably engaged to the opening of a pair of adjacent longitudinal frame elements, and a plurality of curved pressure plates spaced at regular intervals between the opposing ends of the lateral shaft, wherein each pressure plate comprises a connector region configured to mount the pressure plate on the shaft and a plate region extending from the connector region, a terminal end of the plate region comprising a rectangular cut-out configured to accommodate and bias an ear of corn onto a conveyor lane of the dehusking device. The connector region of the pressure plate is made of a more rigid material including sheet metal, while the plate region of the pressure plate is made of a less rigid material including thermoplastic, and at least a portion of the plate region is transparent or translucent. The array includes a first and a second set of parallel lateral shafts, wherein the first set of parallel shafts are interposed between a first pair of longitudinal frame elements and aligned with a first set of conveyor lanes of the dehusking device, and wherein the second set of parallel shafts are interposed between a second pair of longitudinal frame elements and aligned with a second, different set of conveyor lanes of the dehusking device. In some embodiments, the first set of parallel lateral shafts are offset from the second set of parallel lateral shafts, and wherein the first and second pair of longitudinal frame elements have a common longitudinal frame element. Each pressure plate further comprises a stopping element on an underside of the connector region, adjacent to the lateral shaft, the stopping element configured to limit downward motion of the pressure plate, thereby averting contact between the terminal end of the pressure plate and an underlying conveyor lane. In some embodiments, individual pressure plates of a set of the array may be arranged in an imbricated configuration, and the stopping element of a given pressure plate may be further configured to limit upward motion of the pressure plate, thereby averting contact between the terminal end of the pressure plate and an overlying pressure plate of the set.

An exemplary embodiment of a method of increasing dehusking efficiency while maintaining (or reducing) seed loss during dehusking comprises: transporting green corn ears along parallel cradled lanes of a dehusking device from an inlet end to an outlet end, each cradled lane comprising a group of rollers arranged in a non-planar configuration; biasing a given corn ear onto a given cradled lane via an array of pressure plates of a frame assembly mounted to a periphery of the dehusking device, the array of pressure plates aligned with the given cradled lane, the array comprising multiple sets of pressure plates engaged to parallel lateral shafts, the lateral shafts mounted on openings in longitudinal frame elements uniformly distributed between the inlet end and the outlet end, wherein the biasing limits movement of the corn ear out of the given cradled lane thereby increasing the dehusking performance while maintaining (or reducing) seed loss for the corn ear; and while the corn ear travels on the given cradled lane, drawing a husk of the corn ear between the group of rollers, thereby dehusking the corn, and wherein the seed loss is maintained or reduced while increasing the dehusking efficiency. In some embodiments, the given cradled lane is a first cradled lane and the array of pressure plates is a first array aligned with the first cradled lane and wherein the biasing reduces (or maintains) seed loss and increases dehusking efficiency by reducing lateral transfer of the corn ear from the first cradled lane to the second cradled lane, the method further comprising, biasing a second corn ear onto a second cradled lane via a second array of pressure plates, the second array longitudinally offset from the first array, wherein the biasing reduces lateral transfer of the corn ears from the second cradled lane to the first cradled lane. In some embodiments, the method further comprises adjusting a position of engagement of one or more of the parallel lateral shafts with the openings in the longitudinal frame elements to change a parameter of the array of pressure plates, the adjusting performed as a function of one or more of a degree of incline of the dehusking device, a rate of rotation of the group of rollers, and a rate of receiving the green corn ears at the dehusking device.

These and other features and advantages of the present invention will become apparent after a review of the following detailed description of the disclosed embodiments and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is further described with reference to the appended figures showing exemplary embodiments of the present invention, wherein:

FIG. 1 is a top perspective view of a corn dehusking system in accordance with the present disclosure.

FIG. 2 is a schematic comparison between turbulent flow of corn ears in a conventional dehusking system and laminar flow of aligned corn ears in the dehusking system of the present invention.

FIG. 3 is detailed view of a corn alignment system that can be coupled to a dehusking system to increase the dehusking performance and maintain (or reduce) seed losses. FIGS. 4A-B show a detailed view of a pressure plate array of the disclosed dehusking system, and various components thereof, that are used to bias corn ears onto dehusking rollers according to the present invention.

FIGS. 5-6 are perspective views of a single pressure plate of the dehusking system of the present invention.

FIG. 7 is a perspective view of an example lateral shaft onto which individual pressure plates of the present invention are installed.

FIG. 8 shows a detailed view of another example lateral shaft onto which individual pressure plates of the present invention can be installed.

FIG. 9 shows a detailed view of a longitudinal frame element onto which lateral shafts are mounted.

FIG. 10 is a perspective view of a stopping element of a pressure plate system that can be coupled to the example lateral shaft of FIGS. 7-9 to limit downward motion of a pressure plate onto a dehusking surface.

FIG. 11 is a perspective view of a chassis for receiving lateral shafts and pressure plates of a pressure plate system, the chassis couplable to conventional corn dehusking equipment.

FIG. 12 is a high-level flowchart depicting an example method of reducing seed losses during dehusking by improving laminar flow of corn ears over dehusking rollers.

FIG. 13 shows an example embodiment of pressure plate of the dehusking system aligning a corn ear onto a travel path channel over dehusking rollers.

All figures are drawn to scale.

DETAILED DESCRIPTION

According to the present invention, a system is provided for aligning corn ears during dehusking at a corn processing plant. The system comprises a frame assembly that is coupled to (e.g., mounted within or on) a conveyor mechanism (e.g., a conventional conveyor mechanism used for dehusking corn ears, such as in a commercial or research setting) and a pressure plate array that is coupled to the frame assembly. The conveyor mechanism has a dehusking surface with multiple travel paths for conveying ears of corn from an inlet end to an outlet end. In some examples, the conveyor mechanism and dehusking surface comprise conventional dehusking equipment and the frame assembly with the pressure plate array is mounted or fastened (e.g., retrofitted) to the frame assembly. The pressure plate array is mounted so to align with the multiple travel paths of the conveyor mechanism, each pressure plate applying a biasing force to the corns to maintain a substantially laminar flow of the corn ears on the corresponding travel paths. The biasing force also increases the likelihood of corn husks being grabbed and dragged between rollers of the conveyor mechanism, increasing dehusking performance. The biasing force not only aligns the corn ears relative to each other and to the travel paths, but also reduces unwanted drift of the corn ears from one travel path to another. This reduction in drift reduces the need to rework corn ears. In addition, the laminar flow prevents smaller corn ears from getting trapped or swallowed between travel paths, reducing or maintaining associated seed losses. In this way, the dehusking system of the present disclosure improves dehusking efficiency of corn ears as they are conveyed over dehusking rollers of a dehusking apparatus, thereby reducing or maintaining seed losses during dehusking.

The figures provided herein are drawn to scale. Further, dimensions of an example embodiment of the various components are indicated in the figures (in millimeters, where applicable).

FIGS. 1-3 disclose an example embodiment of a corn dehusking system 100 (herein also referred to as a dehusking apparatus), and a method of operating the same, the dehusking system configured to dehusk an ear of corn, such as a corn ear 1 having a length L and a diameter D. As will be elaborated herein, various features of the dehusking system are configured and/or positioned to accommodate and efficiently process the corn ear with the recited dimensions. At least some of the dimensions of the dehusking system are provided in reference to the corn dimensions.

Corn dehusking system 100 comprises a conveyor mechanism 10 with at least one pair of rollers 12 forming a travel path 14 on their surface, the travel path having an inlet end 16 and an outlet end 18.

As such, the conveyor mechanism is primarily responsible for dehusking corn ears placed thereon and may be, for example, a conventional dehusking equipment used for commercial dehusking activities. In some embodiments, each travel path is defined by a group of rollers 20, the group comprising 2, 3, 4, or more rollers operatively coupled to one another. The example embodiment depicted at FIGS. 1 and 3 shows a conveyor mechanism with multiple groups of rollers 20 forming multiple travel paths 14, the travel paths arranged in parallel, and adjacent to each other, for conveying ears of corn from the inlet end 16 to the outlet end 18 and for dehusking the corn ears as they are conveyed. Each group of rollers in the depicted embodiment has four rollers, however, this configuration is only illustrative and not limiting. In one example embodiment, the conveyor mechanism and rollers are parts of a conventional dehusking apparatus of a corn processing plant, such as apparatus used for commercial dehusking functions. The travel path is configured to have a length that is at least 4L from the inlet end to the outlet end. As an example, the travel path may be at least 5L, at least 10L, at least 15L, at least 19L, or at least 20L from the inlet to the outlet end. This enables multiple corn ears to be processed along any given travel path at any given time. During corn processing, each roller in the group of rollers rotates in a defined direction to generate a conveying motion which moves the corn ears from the inlet end towards the outlet end, and wherein the relative rotation of the rollers results in the husk of the ear corn being grabbed and drawn to perform the dehusking process. More specifically, the group of rollers define a dehusking surface 22 of the travel path 14 (shown also at FIG. 13). Features of the dehusking surface 22 are defined at least by the relative arrangement of the multiple rollers in each group 20 as well as their individual surface properties. As one example, where the group of rollers 20 are obliquely arranged relative to one another (wherein at least some of the rollers are not in the same plane as other rollers of the same group, as shown in FIGS. 3 and 13), the travel path 14 may comprise a cradled channel or travel path. In other configurations, such as where the rollers are aligned relative to each other, the travel path may comprise a straight channel or a substantially planar dehusking surface. In still other configurations, adjacent groups of rollers may define adjacent non-parallel channels along the conveyor mechanism.

The group of rollers may include, as a non-limiting example embodiment shown in FIGS. 1 and 3, a first subgroup of outer rollers 12a and a second subgroup of inner rollers 12b, wherein the outer rollers 12a are positioned outer to the inner rollers 12b, and optionally not in the same plane as the inner rollers. In the depicted embodiment, a pair of inner rollers are arranged at a higher plane height than a corresponding pair of outer rollers. The inner rollers rotate away from each other while the outer rollers rotate towards each other (when viewed at an upper surface). As a result, each inner roller and its adjacent outer roller are rotating towards each other (when viewed at an upper surface). The relative rotation of the inner rollers away from each other causes any ear of corn being conveyed through the conveyor mechanism and coming into contact with an upper surface of the inner rollers to be redirected (e.g., thrown) towards an adjacent outer roll. For example, the relative placement of the inner and outer rollers in the group of rollers may result in the creation of a central furrow in the region between the inner rollers and peripheral furrows in the region between the inner roller and the corresponding outer roller. Then, the relative rotation of the inner and outer rollers may translocate a corn ear travelling along the inner furrow to one of the outer furrows, where the dehusking takes place. The relative rotation of each outer roller and its correspondingly adjacent inner roller towards each other causes the ear corn husk to get trapped in the region (e.g., a peripheral furrow) between the outer roller and the adjacent inner roller. And as the rollers rotate towards each other, the trapped husk is drawn through the region, along with the rotating surface of the rollers, while the corn ear remains on the surface of the outer roller, resulting in a dehusking action at this location.

In some embodiments, the arrangement of the rollers in the group as well as the surface features of the rollers (e.g., nature of material used in manufacture of the rollers) may define a coefficient of friction (CoF) of the dehusking surface. Flerein, the dehusking surface may be adapted to have a CoF that is sufficient to dehusk the ears. For example, the dehusking surface may be adapted to have a higher CoF for corn husks than for corn cobs or kernels. In example embodiments, the dehusking surface has a coefficient of friction having a value between 0.01 to 0.50, such as 0.01 to 0.05, 0.05 to 0.10, 0.10 to 0.25, and/or 0.25 to 0.50. During the dehusking process, as the corn ears flow over the travel path, the corn husk gets caught at or between the groups of rollers 20. Due to the rotation of the rollers relative to each other (as discussed above), in combination with the difference in CoF, the trapped husk is drawn away from the dehusking surface while the dehusked corn ear continues to travel along the travel path. In some embodiments, in addition to or in place of the nature of the material used in the manufacture of the rollers, the CoF of the dehusking surface may be achieved through the incorporation of surface features onto the surface of the rollers, including grooves, ridges, channels, bumps, ribs, fins, spokes, etc., that are etched or molded onto the surface of the rollers.

Due to the mechanical nature of the dehusking process, the path of a corn ear flowing on the conveyor mechanism may be disrupted by the motion, vibrations, and general turbulence experienced at the dehusking surface. During corn ear travel on the conveyor mechanism, there is a high frequency of impact between the corn and the roller surface. The resulting turbulent flow, in the absence of corn alignment, is shown at FIG. 2 (upper panel). The turbulent flow can cause the corn ears to bounce round, resulting in an increased probability of small corn ears being swallowed between the rollers, decreased probability of ear corn accommodation on the dehusking surface, and decreased probability of contact with the rollers. This causes the husk of some corn ears to not be completely removed, requiring them to be reworked. Overall, the turbulent flow decreases dehusking efficiency, increases seed losses and the need to rework any corn ears that have been swallowed or thrown off the conveyor mechanism.

To address this, the dehusking system 100 further comprises a mounting shaft 24, 25 (herein also referred to as lateral mounting element, lateral frame element, or lateral structural element) coupled to the conveyor mechanism and positioned above the group of rollers at a height in the range of 2D to 10D and a pressure plate 26. The mounting structure may be included as part of a frame assembly 28 that includes additional lateral and longitudinal structural elements, on which the pressure plate is mounted. Details of the frame assembly are provided below. A first embodiment of a lateral mounting shaft 24 is detailed at FIGS. 4 and 7, while a second embodiment of a lateral mounting shaft 25 is detailed at FIGS. 8-9. In the depicted example, the dehusking system comprises mounting shafts of the both the first and second embodiment, however, in other examples, only a single type of mounting shaft may be incorporated.

The mounting shaft 24, 25 may be included in a frame assembly 28 of the dehusking system. The frame assembly 28 is coupled to the body 31 (or housing) of the conveyor mechanism. As detailed at FIGS. 1, 3, and 11, frame assembly 28 comprises a chassis 30 having opposing side walls 32 and opposing end walls 34. The chassis may be substantially quadrangular and may be configured to match the dimensions of the body 31 of the conveyor mechanism to which it is coupled. The body 31 or housing of the conveyor mechanism defines an inner volume of the conveyor mechanism within which the groups of rollers are housed. In some embodiments, the frame assembly is coupled to the frame of the conveyor mechanism such that the entirety of the frame assembly is also included within the volume and within the body of the conveyor mechanism while being positioned above the rollers. In other embodiments, the frame assembly is coupled to the body of the conveyor mechanism such that at least a portion of the frame assembly lies within the volume of the conveyor mechanism, above the rollers, while another portion of the assembly is mounted above the conveyor mechanism and over the rollers, outside of the housing. The frame assembly can be coupled to the conveyor mechanism by any known coupling method, such as by welding, use of an adhesive, use of a fastener (e.g., screw, rivet, nuts and bolts), etc.

In still further embodiments, the frame assembly may be manufactured alongside the conveyor mechanism housing as a single structure.

Opposing side walls 32 of the chassis are arranged parallel to travel paths 14, coupled to the inner surface of corresponding opposing wide walls of the body 31 of the conveyor mechanism. The opposing end walls 34 are arranged perpendicular to the travel paths of the conveyor mechanism, at the inlet and outlet ends. A plurality of longitudinal frame elements 36 are interposed between the opposing end walls 34, each longitudinal frame element 36 comprising a plurality of evenly spaced openings 38 along a length of the longitudinal frame element. A detailed view of the longitudinal element is shown at FIG. 9. In some embodiments, a length of a given longitudinal frame element extends from one end wall 34 of the chassis to an opposing end wall 34. A lateral mounting shaft 24, 25 is received in the opening 38 to engage the lateral shaft to the longitudinal element. In one example embodiment, the opening may be a circular, oval, or elliptical opening that is not continuous with the upper surface of the longitudinal frame element. Still other shaped openings are possible. In other embodiments, the opening may be provided as a recess, notch, or groove extending inwards from an upper surface of the longitudinal frame element. The lateral mounting shaft 24, 25 may be held in place on the longitudinal element via the notch or groove. A number and positioning of longitudinal elements between the end walls of the chassis may be adjusted based on the configuration and dimensions of the specific conveyor mechanism or dehusking equipment to which the frame is coupled. For example, adjacent longitudinal frame elements may be positioned such that they are separated by an integral number of parallel conveyor lanes or travel paths of the underlying dehusking device. For example, adjacent longitudinal frame elements 36 may be separated by at least 2 travel paths. In the example depicted at FIGS. 1 and 3, the longitudinal elements of the frame assembly are aligned to enable the easy accommodation and installation of pressure plates when the frame is coupled to a dehusking equipment having 3 grid doors (a central smaller door and lateral larger doors).

One or more pressure plates 26 are suspended from lateral mounting shaft 24, 25. In one example, mounting shaft 24 is designed to be longer (FIGS. 4 and 7), to have at least one end of the shaft coupled to an end wall of the frame assembly, and to accommodate three pressure plates thereon. In comparison, mounting shaft 25 is designed to be shorter (FIGS. 8-9), to be coupled to longitudinal frame elements that are not at lateral ends or end walls of the frame assembly, and to accommodate two pressure plates thereon. These differences may be provided to facilitate the installation of the shafts in a dehusking equipment having a 3 grid door configuration with a central door smaller than lateral doors.

In some embodiments, a single lateral mounting shaft is coupled between openings of adjacent longitudinal elements (or between a side wall and an adjacent longitudinal element) and one or more pressure plates are suspended from the mounting shaft, as illustrated with reference to mounting shafts 24, 25. Further, mounting shafts may be arranged coaxially, in parallel, or offset from each other. In the depicted example of FIG. 3, a first mounting shaft 24a is arranged coaxial to mounting shaft 24b and parallel to mounting shaft 24c. Mounting shaft 25a is arranged parallel to mounting shaft 25b. Further, mounting shafts 24a, b, c are offset from (that is, not aligned with) mounting shafts 25a, b.

In other embodiments, a single lateral mounting shaft may be coupled between corresponding openings of the opposing side walls, and a plurality of pressure plates may be suspended, at uniform distances, along a length of the shaft, between the opposing side walls. As detailed below, this modular arrangement allows a pressure plate array to be created on the frame assembly by adjusting the position of longitudinal frame elements, lateral mounting shafts, and number and position of pressure plates suspended therefrom.

Each pressure plate 26 comprises a connector region 40, a terminal end 42, and a plate region 44 positioned between the terminal end and the connector region. The pressure plate 26 is connected at its connector region 40 to the mounting shaft 24, 25, as shown at FIGS. 4-6 and 8. In the depicted example, the connector region has a clamp or hooked structure which allows the pressure plate to be coupled to (e.g., suspended from) the mounting shaft 24, 25 while also enabling rotation of the pressure plate around the shaft. However, other fastening or connecting structures may be used without departing from the scope of this invention (e.g., hooks, springs, etc.). When mounted, the pressure plate defines a travel path channel (TPC) 46 between its terminal end and the at least one pair of rollers (or the dehusking surface), as shown in FIG. 2. The TPC 46 has a height in the range of 0.9D to 2D. The pressure plate is configured to allow an ear of corn to pass through the TPC while applying a biasing force on the corn ear as it passes under the pressure plate, as best shown at FIG. 2 (lower panel). The biasing force is passively applied on the underlying corn ears by virtue of the weight and structure of the pressure plate. The inventors herein have recognized that only a slight amount of pressure is required to provide the laminar flow and that large amount of pressure application can exacerbate the turbulent flow. Accordingly, the pressure plate is sized and weighted to apply just enough pressure to bias the corn. As a result of the application of this biasing force, the corn ear is more likely to align with the underlying travel path 14 and smoothly flow over the rollers of the conveyor mechanism. The consequent laminar flow, in the presence of corn alignment, is shown at FIG. 2 (lower panel). This arrangement results in low impact frequency, increased grip to remove the husk, decreased probability to swallow small ear corn; increased probability of ear corn accommodation, and increased probability of contact of dehusking rollers with the corn ear. Overall, dehusking efficiency increases, seed losses decrease, and the need to rework corn ears also decreases.

As best shown at FIGS. 5-6, each pressure plate 26 comprises a connector region 40 pivotably engaging the pressure plate to a corresponding lateral element or mounting shaft 24, 25 and a plate region 44 extending from the connection region. The plate region may have a terminal cut-out 48 in any shape, such as a rectangular cut-out, as depicted. The terminal rectangular cut-out extends from an end of the plate region towards the connection region and is configured to accommodate therein a corn ear being conveyed on an underlying travel path. In addition, the cut-out enables the pressure plate to bias an ear of corn, accommodated in the cut out, onto a conveyor lane of the dehusking device. When no corn ears are being conveyed, the cut-out can accommodate at least some of the group of rollers of the underlying dehusking surface. In the depicted example, at FIG. 1 and 3, the cutout is shown accommodating the two rollers of the upper plane of group of non-planar rollers clustered in an oblique arrangement.

In some embodiments, different regions of the pressure plate are configured with distinct attributes to further improve the dehusking efficiency, as shown at least at FIGS. 5-6. For example, while the roller surface has a coefficient of friction, or CoF, equal to X (e.g., between 0.10 to 0.50), the plate region 44 of the pressure plate may be constructed of a material that results in the plate region having a CoF that is less than X (e.g., between 0.01 to 0.50). This enables the pressure plate to apply a biasing force that aligns the corn ears on the dehusking surface without detracting from the ability of the underlying rollers to grab and draw out the husk. As another example, the connecting region may be constructed of a first material (e.g., sheet metal, or steel) that is more rigid while the plate region is constructed of a second, different material that is less rigid (e.g., polycarbonate, thermoplastic, or a different sheet metal). In other embodiments, the plate region and connection region may have thickness, and/or different degrees of transparency. As shown at FIG. 13, in one example embodiment, the plate region may have a central section that is transparent while a periphery of the plate region, including the terminal cut-out is opaque. This allows for visualization of the corn ear being biased onto the dehusking surface by the given pressure plate.

In some embodiments, as shown at FIGS. 5-6, the pressure plate may be curved having an angle of curvature A that is between 5 and 25 degrees, such as 15 degrees. Further, the plate may have a radius of curvature R, as shown. The curvature of the pressure plate may be selected to maximize contact of the plate region of the pressure plate with corn ears traveling on the dehusking surface while reducing contact of the terminal end of the pressure plate with the dehusking surface. In other embodiments, the pressure plate is not curved.

As elaborated below, and shown at FIGS. 1, 3, 4 and 8, the dehusking system may include multiple such pressure plates arranged in an array. For example, the system may comprise at least a first and a second pressure plate mounted on respective mounting shafts and arranged in an imbricated configuration. A stopping element 50 provided on the underside of a connecting region of a given pressure plate (shown in detail at FIGS. 4A-B and 10) is configured to limit downward motion of the pressure plate, thereby averting contact between the ter inal end of the pressure plate and an overlying pressure plate of the imbricated set. The stopping element 50 also maintains a separation between the plate region and the dehusking surface (e.g., between the plate and an uppermost of the group of obliquely arranged rollers). In this way, the stopping element limits downward motion of the pressure plate to create the travel path channel (TPC) between the terminal end of the pressure plate and the upper surface of the rollers (or the dehusking surface). The stopping element achieves two main functions: first, it prevents the pressure plate from making contact with the dehusking rolls (or any portion of the dehusking surface) when no corn ear is passing through; and second, it maintains the pressure plate at a defined height above the rollers so that when the ear corn is passing thought, an appropriate amount of biasing force is applied on the corn ear. In some embodiments, the stopping element may be further configured to limit upward motion of the pressure plate to prevent contact between the terminal end of the given pressure plate and the plate region of another pressure plate in the array that is positioned in an imbricated or partially overlying configuration. The stopping element may be mounted on the mounting shaft 24, 25, below the pressure plate such that the stopping element 50 can be seen through a cut-out 27 in the connector region of the pressure plate, as best shown at FIGS. 4A-B and 8.

The pressure plate 26 may be included in a plate assembly 52 of the dehusking system. As shown at FIGS. 1 and 3, the plate assembly may comprise an array 54 of lateral shafts engaged to longitudinal frame elements via the openings, each lateral shaft of the array supporting one or a plurality of pressure plates extending from the shaft at an angle to bias corn ears onto the travel paths formed on the conveyor mechanism by the groups of rollers. Herein, the multiple travel paths are parallel travel paths divided into groups of travel paths by the plurality of longitudinal frame elements interposed between the opposing end walls. For example, each travel path may be aligned with a travel path channel formed by a corresponding group of dehusking rollers above which the pressure plates are mounted. In the depicted embodiment, two longitudinal frame elements divide the travel paths into three groups. However, it will be appreciated that this is not limiting and that any number of longitudinal frame elements may be similarly provided. Each lateral mounting shaft extends between a pair of adjacent longitudinal frame elements and is rotatable about a shaft axis (X-X) that runs perpendicular to a longitudinal axis (Y-Y) of the longitudinal frame elements. In this way, the lateral mounting shafts and longitudinal frame elements are engageable to create a lattice structure in the frame assembly. Pressure plates are distributed at uniform intervals along this lattice structure. As detailed at FIGS. 3 and 4, a plurality of equally spaced pressure plates are engaged to each lateral shaft. In one example embodiment, each lateral shaft is configured to support between 2-5 plates, such as 2, 3 or 4 pressure plates.

As shown at FIGS. 1, and 3, the array of lateral shafts includes a first set of parallel lateral elements (such as elements 24a, 24c), each lateral element of the first set extending between a first pair of adjacent longitudinal frame elements, and a second set of parallel lateral elements (such as elements 25a, 25b), each lateral element of the second set extending between a second, different pair of adjacent longitudinal frame elements. The first set of parallel lateral elements is aligned with a first travel path defined by a first group of rollers while the second set of parallel lateral elements is aligned with a second travel path defined by a second, adjacent group of rollers. The first pair and the second pair have a single common longitudinal frame element (36). A separation between adjacent lateral elements of a given set of lateral elements (e.g., between 24a and 24c) is less than a length of one pressure plate. As a result, along the length of a longitudinal element, pressure plates may be arranged in an imbricated or partially overlapping manner. The first set of lateral elements in the array may be aligned relative to the second set to create a uniform array. Alternatively, the first set of lateral elements in the array may be staggered relative to the second set of lateral elements (e.g, 24a, c offset from 25a, b), creating an offset array, as shown in FIGS. 1 and 3.

In some embodiments, the chassis, including the position of the longitudinal elements, of the frame assembly, is permanently affixed to the conveying mechanism, such as by welding. An operator may then adjust the position of individual lateral mounting shafts, each with the plurality of pressure plates, to adjust the configuration of the array based on various considerations. By adjusting the configuration, a parameter of the array can be adjusted. For example, the positioning maybe adjusted based on one or more of the feed rate of the apparatus (e.g., the number of corn ears being conveyed from the inlet to the outlet end of the conveying mechanism over a unit of time), the angle of incline of the apparatus, and the rotation of the rollers. In one example, when the feed rate is higher, and more corn ears are expected to be processed, lateral mounting shafts may be coupled at smaller intervals along the length of the longitudinal frame element (e.g., shafts coupled to each opening of every longitudinal element). Further, in embodiments, the adjacent lateral mounting shafts may be aligned (embodiment not shown) or staggered (as shown in FIG. 1 and 3) relative to each other. In comparison, when the feed rate is lower, and fewer corn ears are expected to be processed, lateral mounting shafts may be coupled at larger intervals along the length of the longitudinal frame element (e.g., shafts coupled to every other opening of every longitudinal element).

Since the frame assembly is mounted to a frame of the conveyor mechanism 10, and the pressure plate is mounted to the movable mounting plates, the arrangement enables the pressure plate array to be easily retrofitted or incorporated into an existing dehusking apparatus to increase the dehusking efficiency and reduce (or maintain) the seed losses of the apparatus. This allows for easy installation and removal of the pressure plates, providing a “plug and play” configuration.

In this way, a dehusking system is provided that improves contact between corn ears and a dehusking surface, reducing corn displacement. As a result, a larger number of corn ears can be dehusked efficiently with reduced seed loss.

FIG. 12 shows a high-level flowchart of an example method 1200 of dehusking corn ears with corn ear alignment to reduce seed losses.

At 1202, the method includes transporting green corn ears along parallel travel paths of a dehusking device from an inlet end to an outlet end. In one example, the travel paths include parallel cradled lanes, each cradled lane comprising a group of rollers arranged in a non-planar configuration.

At 1204, the method includes biasing a given corn ear onto a given cradled lane via an array of pressure plates of a frame assembly mounted to a periphery of the dehusking device, the array of pressure plates aligned with the given cradled lane, the array comprising multiple sets of pressure plates engaged to parallel lateral shafts, the lateral shafts mounted on openings in longitudinal frame elements uniformly distributed between the inlet end and the outlet end. The biasing of the corn ears by the pressure plates comprises, at 1206, limiting movement of the corn ear from the given travel path to another travel path (e.g., out of the given cradled lane to an adjacent cradled lane), thereby reducing seed loss. In one example, the given cradled lane is a first cradled lane and the array of pressure plates is a first array aligned with the first cradled lane, and the biasing reduces seed loss by reducing lateral transfer of the corn ear from the first cradled lane to the second cradled lane. Similarly, a second corn ear is concurrently biased onto a second cradled lane via a second array of pressure plates, the second array longitudinally offset from the first array, and the biasing reduces lateral transfer of the corn ears from the second cradled lane to the first cradled lane.

The biasing also comprises, at 1208, limiting movement of the corn ear from the given travel path to off the dehusking device (e.g., out of the given cradled lane to off the conveyor), thereby reducing reworking losses.

In some embodiments, prior to dehusking, an operator may adjust a position of engagement of one or more of the parallel lateral shafts with the openings in the longitudinal frame elements to change a parameter of the array of pressure plates. The adjusting may be performed as a function of one or more of a degree of incline of the dehusking device, a rate of rotation of the group of rollers, and a rate of receiving the green corn ears at the dehusking device.

Finally, at 1210, the method includes, while the corn ear travels on the given travel path, drawing a husk of the corn ear between and through the group of rollers of the dehusking device, thereby dehusking the corn. In this way, the method reduces seed loss while maintaining dehusking efficiency.

Example dimensions of the frame assembly including dimensions of the lateral and longitudinal frame elements, pressure plates and stopping elements is provided in the figures of US provisional application No. 63/176,967 from which the instant application claims priority and the contents of which are included herein in their entirety.

In example embodiments, each pressure plate is about 200mm wide (e.g., 210mm wide) and about 500mm long (e.g., 475mm long) with an angle of curvature between 5-25degrees (e.g., 15 degrees) and a radius of curvature between 1 and 25mm (e.g., 14mm). In embodiments, the terminal cutout of the pressure plate is between 100-200mm wide (e.g., 140, 141 or 142mm) and between 40-80mm deep (e.g., 63, 64 or 65mm deep). In embodiments, the mounting shafts are between 200-800mm long (e.g., 350, 400, 500, 550, 600, 650, 700 or 750mm). In embodiments, the stopping elements are between 20 and 50mm long (e.g., 30mm long) and having a central aperture with a radius of about 5 to 20mm (e.g., 10mm). In embodiments, the frame elements are between 1000-4000mm long (e.g., 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2100, 2200, or 2300mm long) with openings spaced every 100-500mm (e.g., every 100, 110, 120, 125, 130, 150, 160, 180, 200, 210, 220, 220, 240, 250, 260, 300, 320, 350, 400, 450 or 500mm). The openings may be 5-30mm in depth or diameter based on their shape (e.g., 10, 12, 14, 16, 18, 20, 25 mm in depth or diameter).

The foregoing description and drawings comprise illustrative embodiments of the present inventions. The foregoing embodiments and the methods described herein may vary based on the ability, experience, and preference of those skilled in the art. Merely listing the steps of the method in a certain order does not constitute any limitation on the order of the steps of the method. The foregoing description and drawings merely explain and illustrate the invention, and the invention is not limited thereto, except insofar as the claims are so limited. Those skilled in the art that have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention.

Claims

CLAIMS:

1. A system for aligning corn ears, comprising: a conveyor mechanism with groups of rollers forming multiple travel paths for conveying ears of corn from an inlet end to an outlet end; a frame assembly mounted above the conveyor mechanism comprising a chassis having opposing side walls and opposing end walls, a plurality of longitudinal frame elements interposed between the opposing end walls, each longitudinal frame element comprising a plurality of evenly-spaced openings along a length of the longitudinal frame element; and a plate assembly comprising an array of lateral shafts engaged to longitudinal frame elements via the openings, each lateral shaft of the array supporting a plurality of curved pressure plates extending from the shaft at an angle to bias corn ears onto the travel paths.

2. The system of claim 1, wherein the rollers are obliquely-arranged rollers, wherein each group of obliquely-arranged rollers includes non-planar rollers, wherein the multiple travel paths are parallel travel paths divided into groups of travel paths by the plurality of longitudinal frame elements interposed between the opposing end walls, and wherein each travel path is a cradled travel path.

3. The system of claim 1 or 2, wherein the chassis is substantially quadrangular, wherein each lateral element extends between a pair of adjacent longitudinal frame elements and is rotatable about a shaft axis perpendicular to a longitudinal axis of the longitudinal frame elements, wherein a plurality of equally-spaced pressure plates are engaged to each lateral shaft, and wherein the opposing side walls of the chassis are parallel to the inlet end and the opposing end walls are parallel to the outlet end.

4. The system of claim 3, wherein each pressure plate comprises a connection region pivotably engaging the pressure plate to a corresponding lateral shaft, and a plate region extending from the connection region, the plate region having a terminal cut-out, optionally terminal rectangular cut-out.

5. The system of claim 4, wherein the connection region is made of a first material and the plate region is made of a second, different material less rigid than the first material.

6. The system of claim 4 or 5, wherein the terminal cut-out extends from an end of the plate region towards the connection region and is configured to accommodate therein a corn ear being conveyed on an underlying travel path.

7. The system of any of claims 4-6, further comprising a stopping element mounted on the lateral shaft, coaxial to the pressure plate and positioned on an underside of the pressure plate at the connection region, the stopping element configured to maintain a separation between the plate region and an uppermost of the group of obliquely arranged rollers.

8. The system of any of clai s 1-7, wherein the array of lateral shafts includes a first set of parallel lateral shafts, each lateral shaft of the first set extending between a first pair of adjacent longitudinal frame elements, and a second set of parallel lateral shafts, each lateral shaft of the second set extending between a second, different pair of adjacent longitudinal frame elements, and wherein the first set of parallel lateral shafts is aligned with a first travel path and the second set of parallel lateral elements is aligned with a second travel path parallel to the first travel path.

9. The system of claim 9, wherein the first pair and the second pair have a common longitudinal frame element.

10. The system of claim 8 or 9, wherein a separation between adjacent lateral shafts of the first or second set of lateral shafts is less than a length of one pressure plate.

11. The system of any of claims 8-10, wherein the first set of lateral shafts in the array are staggered relative to the second set of lateral shafts.

12. A corn alignment system couplable to a corn dehusking device, comprising: a frame assembly mountable on a periphery of the dehusking device, the frame assembly comprising a quadrangular chassis having opposing side walls and opposing end walls, a plurality of longitudinal frame elements interposed between the opposing end walls, wherein each longitudinal frame element comprising a plurality of evenly-spaced openings along a length of the longitudinal frame element, and wherein adjacent longitudinal frame elements are separated by an integral number of parallel conveyor lanes of the underlying dehusking device; and a plate assembly comprising an array of parallel lateral shafts, each lateral shaft of the array comprising opposing shaft ends rotatably engaged to the opening of a pair of adjacent longitudinal frame elements, and a plurality of curved pressure plates spaced at regular intervals between the opposing ends of the lateral shaft, wherein each pressure plate comprises a connector region configured to mount the pressure plate on the shaft and a plate region extending from the connector region, a terminal end of the plate region comprising a rectangular cut-out configured to accommodate and bias an ear of corn onto a conveyor lane of the dehusking device.

13. The system of claim 12, wherein the connector region of the pressure plate is made of a more rigid material including sheet metal, wherein the plate region of the pressure plate is made of a less rigid material including thermoplastic, and wherein at least a portion of the plate region is transparent or translucent.

14. The system of claim 12 or 13, wherein the array includes a first and a second set of parallel lateral shafts, wherein the first set of parallel shafts are interposed between a first pair of longitudinal frame elements and aligned with a first set of conveyor lanes of the dehusking device, and wherein the second set of parallel shafts are interposed between a second pair of longitudinal frame elements and aligned with a second, different set of conveyor lanes of the dehusking device.

15. The system of claim 14, wherein the first set of parallel lateral shafts are offset from the second set of parallel lateral shafts, and wherein the first and second pair of longitudinal frame elements have a common longitudinal frame element.

16. The system of any of claims 12-15, wherein each pressure plate further comprises a stopping element on an underside of the connector region, adjacent to the lateral shaft, the stopping element configured to limit downward motion of the pressure plate, thereby averting contact between the terminal end of the pressure plate and an underlying conveyor lane.

17. The system of claim 16, wherein individual pressure plates of a set of the array are arranged in an imbricated configuration, and wherein the stopping element of a given pressure plate is further configured to limit upward motion of the pressure plate, thereby averting contact between the terminal end of the pressure plate and an overlying pressure plate of the set.

18. A method of reducing seed loss from corn during dehusking, comprising: transporting green corn ears along parallel cradled lanes of a dehusking device from an inlet end to an outlet end, each cradled lane comprising a group of rollers arranged in a non-planar configuration; biasing a given corn ear onto a given cradled lane via an array of pressure plates of a frame assembly mounted to a periphery of the dehusking device, the array of pressure plates aligned with the given cradled lane, the array comprising multiple sets of pressure plates engaged to parallel lateral shafts, the lateral shafts mounted on openings in longitudinal frame elements uniformly distributed between the inlet end and the outlet end, wherein the biasing limits movement of the corn ear out of the given cradled lane thereby reducing seed loss; and while the corn ear travels on the given cradled lane, drawing a husk of the corn ear between the group of rollers, thereby dehusking the corn, and wherein the seed loss is reduced while maintaining dehusking efficiency.

19. The method of claim 18, wherein the given cradled lane is a first cradled lane and the array of pressure plates is a first array aligned with the first cradled lane and wherein the biasing reduces seed loss by reducing lateral transfer of the corn ear from the first cradled lane to the second cradled lane, the method further comprising, biasing a second corn ear onto a second cradled lane via a second array of pressure plates, the second array longitudinally offset from the first array, wherein the biasing reduces lateral transfer of the corn ears from the second cradled lane to the first cradled lane.

20. The method of claim 19, further comprising, adjusting a position of engagement of one or more of the parallel lateral shafts with the openings in the longitudinal frame elements to change a parameter of the array of pressure plates, the adjusting performed as a function of one or more of a degree of incline of the dehusking device, a rate of rotation of the group of rollers, and a rate of receiving the green corn ears at the dehusking device.

21. A corn dehusking system for dehusking an ear of corn, the corn ear having a length L and a diameter D, the system comprising: a conveyor mechanism with at least one pair of rollers forming a travel path having an inlet end and an outlet end, wherein the travel path has a length at least 4L from the inlet end to the outlet end, and wherein the at least one pair of rollers include a dehusking surface having a coefficient of friction sufficient to dehusk the ear as it travels over the rollers; a mounting shaft positioned above the pair of rollers at a height in the range of 2D to 10D; and a pressure plate having a connector region, a terminal end, and a plate region therebetween, wherein the pressure plate is connected at its connector region to the mounting shaft, and wherein the pressure plate defines a travel path channel (TPC) between its a terminal end the at least one pair of rollers, the TPC having a height in the range of 0.9D to 2D and configured to allow the ear of corn to pass therethrough.

22. The system of claim 21, wherein the pressure plate has a length in the range of 2L to 10L, a width in the range of 2L to 10L, and wherein the travel path has a length in the range o 10L to 20L.

23. The system of claim 21 or 22, wherein the pair of rollers have a surface having a coefficient of friction X, and wherein the plate region of the pressure plate has a coefficient of friction less than the coefficient of friction X of the roller surface.

24. The system of any one of claims 21-23, wherein the pressure plate is curved.

25. The system of any one of claims 21-24, further comprising a stopping element coaxially coupled to the mounting shaft on an underside of the pressure plate, the stopping element configured to maintain a travel path channel (TPC) between the plate region and an uppermost of the group of obliquely arranged rollers.

26. The system of any one of claims 21-25, further including a second pressure plate arranged in an imbricated configuration relative to the first pressure plate, and wherein the stopping element of a given pressure plate is further configured to limit upward motion of the pressure plate, thereby averting contact between the terminal end of the pressure plate and an overlying pressure plate of the set.