WO2012074417A1

WO2012074417A1 - Article diverter

Info

Publication number: WO2012074417A1
Application number: PCT/NZ2011/000252
Authority: WO
Inventors: Eric Adrianus Plessius; Sheldon Phillip White; Shon Cornelius Franciscus Van Tiel
Original assignee: Compac Technologies Limited
Priority date: 2010-12-03
Filing date: 2011-12-05
Publication date: 2012-06-07

Abstract

The invention relates to a method, an apparatus and a system for controlling the motion of an article. More particularly, the invention relates to diverting an article moving in a first trajectory by impinging or substantially impinging the article with one or more fluid streams so as to control or adjust the motion of the article.

Description

ARTICLE DIVERTER

FIELD OF INVENTION

The invention relates to a method, an apparatus and a system for controlling the motion of an article. More particularly, the invention relates to a method, an apparatus and a system that uses fluid propulsion means for diverting the article, in particular fruit, although the invention has wider application.

BACKGROUND

Processing lines for articles such as fruit often require the article moving at a high speed to change direction. In many instances, there will be limited space in which such a change can be made.

In some known arrangements, the articles are redirected by the use of a curtain. In particular, the articles are conveyed at a high speed into the curtain, and are slowed by the impact thereon. While a suspended curtain provides some damping or cushioning, the articles are often damaged. For example, fruit may be bruised, affecting the sale price of the fruit.

In addition, as a result of the impact, articles may leave behind a residue or the like on the curtain. Consequently, the curtain will need to be cleaned periodically, which leads to increased costs and downtime for the apparatus.

One prior art system is described in United States patent number 7,121,399, granted to Mills on 17 October 2006 (hereafter referred to as Mills). Broadly, Mills describes a system including a pneumatic diverter that removes a small fruit from a pair of rollers.

The article is received on a conveyor belt, comprising multiple pairs of rollers. Each pair of rollers is arranged so that the article sits in the valley created between the two rollers.

Each fruit is then directed to an inspection area to sort and/or reject fruit based on predetermined criteria. Once sorted, the pneumatic diverter directs the fruit to an output section.

The pneumatic diverter comprises an electrical solenoid controlled air valve interconnecting a source of compressed air and a nozzle to divert the fruit off the rollers as the fruit passes by the nozzle, which may be positioned alongside, above or below the fruit. The pressure of the air ejection may be varied depending on the fruit size, weight or other factors. The fruit then impacts one or more deflectors to direct the fruit to the output section.

Mills provides that the deflectors should be made of material that will minimise the chance that the fruit will be damaged. For example, the deflectors may be made of a rigid, rubberised fabric. In some cases, the deflectors may not need to be used, if the fruit will naturally move towards the output section.

The use of deflectors presents the same problem previously described in relation to curtains. A further problem with the system described in Mills is that if the deflectors are not used, a large area may be needed for the fruit to travel to their destination. This therefore may not be suitable where there is limited space.

There is therefore a need for an alternative means of controlling the motion of articles moving at high speeds.

It is an object of the invention to provide an improved method, an improved apparatus and an improved system for controlling the motion of articles, particularly fruit. Alternatively, it is an object of the invention at least to ameliorate one or more of the aforementioned problems in article diversion.

Alternatively, it is an object of the invention at least to provide the public with a useful choice.

Other objects of the present invention may become apparent from the following description.

SUMMARY OF THE INVENTION

According to a first aspect of the invention, there is provided a method for diverting an article moving in a first trajectory, the method comprising: impinging or substantially impinging the article with one or more fluid streams so as to control or adjust the motion of the article.

Preferably, the one or more streams adjust the first trajectory to a second trajectory.

Preferably, the adjusting directs the article towards a desired destination.

Preferably, the adjusting is controlled to ensure that the article is not damaged by the one or more streams. Preferably, the adjusting comprises decelerating the article in a first direction and/or accelerating the article in a second direction.

Preferably, the method comprises conveying the article on conveyor means prior to the impinging. Preferably, the method comprises ejecting the article from the conveyor means during and/or after the conveying and before, during and/or after the impinging.

More preferably, articles are ejected while they are conveyed and then impinged with the one or more streams to control subsequent motion thereof.

Preferably, the ejecting is achieved using fluid propulsion means although mechanical means of ejection are also within the scope of the invention.

In broad terms, the one or more streams act as a substitute for a suspended curtain, providing a fluid wall to deflect the articles. However, the invention provides further advantages in that the level of control over the motion of the article is much greater than that achievable with a suspended curtain as will become apparent below. Thus, the adjusting is performed without physical contact with the article, reducing damage and improving hygiene where the articles are foodstuffs.

The fluid may be a liquid, a gas or a mixture thereof. Preferably, the fluid comprises air or an air mixture.

Preferably, the article comprises one or more items of fruit, such as cherries or tomatoes. While the invention has application to essentially any article that requires controlling while in flight, it has particular application to smaller fruits that damage easily on impact.

Preferably, one or more of the pressure, duration, direction, timing and area of contact of at least one of the one or more streams are controllable to ensure that the article is not damaged by the adjusting.

Preferably, one or more of the pressure, duration, direction, timing and area of contact of at least one of the one or more streams are controllable to determine the second trajectory.

According to one embodiment, the force applied to the articles is increased by increasing the surface area of the article to which the one or more streams are applied. For example, according to a preferred embodiment, a nozzle with an elongated aperture is used to produce a curtain of fluid, preferably air. This can avoid high localised pressures that may damage an article. Alternatively, multiple streams such as pinhole-type nozzles can be used, enabling each individual stream to exert less pressure and reducing localised forces. Additionally or alternatively, the pressure of the one or more streams may be varied. For example, the pressure may be higher when the articles are farther away from the fluid propulsion means. The pressure may then be reduced as the articles move towards the fluid propulsion means but increased again as the trajectories of the articles better conform to that of the streams.

The force applied to the articles may also be controlled by varying the direction of the one or more streams and/or by using multiple streams that gradually divert the articles. For example, a first stream may be used to impart sideways motion to the article with streams later used to impart reverse or rearwards motion, including at increasing levels, such as by varying the angle of impact of the one or more streams. Alternatively, the source of one or more streams may, for example, be arranged to pivot.

Additionally or alternatively, the length of time a stream is applied to the articles may be varied. Included within this aspect is applying the streams in a pulsed manner, preferably such that the stream pressure and/or the length of time of the "on portion" or "off portion" of each pulse varies as the article moves along its path.

The stream(s) may be controlled based on a predicted or actual path of the articles. In the case of the latter, sensing means are provided to track the articles with control being adaptive based on a detected position.

According to a second aspect of the invention, there is provided an apparatus for diverting an article moving in a first trajectory, the apparatus comprising: means for impinging or substantially impinging the article with one or more fluid streams so as to control the motion of the article.

Preferably, the means for impinging comprises fluid propulsion means.

Preferably, the fluid propulsion means comprises one or more nozzles adapted to be coupled to a high pressure fluid source. Preferably, the article comprises one or more items of fruit, more preferably cherries or tomatoes. Preferably, the fluid propulsion means is adapted to adjust the first trajectory to a second trajectory.

Preferably, the fluid propulsion means is adapted to direct the article towards a desired destination. Preferably, the fluid propulsion means is adapted to be controlled to ensure that the article is not damaged by the one or more streams. To this end, the apparatus may include control means or be configured to receive control signals from remote control means.

Preferably, the fluid propulsion means is adapted to decelerate the article in a first direction and/or accelerate the article in a second direction.

Preferably, the fluid propulsion means is configured to provide an increased contact area between the article and the stream(s). According to preferred embodiments, this is achieved by configured an outlet of the fluid propulsion means to be in the form of an elongate slit, thereby generating a curtain of air. Alternatively, a plurality of more conventional circular nozzles may act in parallel on an article.

Preferably, one or more of the pressure, duration, direction, timing and area of contact of at least one of the one or more streams are controllable to ensure that the article is not damaged by the adjusting. Such control may be effected using the aforementioned control means.

Preferably, one or more of the pressure, duration, direction, timing and area of contact of the at least one of the one or more streams are controllable to determine the second trajectory. Embodiments of the invention may use multiple sets of apparatus of the second aspect, each providing control of the motion of an article during a different portion of its path. Additionally or alternatively, plural fluid propulsion means may be provided, again, each controlling the motion of the articles at various stages along their path.

According to a third aspect, there is provided an apparatus for ejecting an article from a carrier of a conveyor system, the apparatus comprising: fluid propulsion means adapted to expel one or more fluid streams at or substantially at the article such that sufficient force is generated to remove the article from the carrier.

Preferably, said fluid propulsion means is adapted to avoid causing substantial damage to the article.

Preferably, the fluid propulsion means is controllable so as to vary any one or more of the pressure, direction, duration of application and surface area of application to the article of the stream(s). The number of applied streams may additionally or alternatively be controlled. Preferably, the fluid propulsion means is adapted to provide an increased area of contact with the stream(s) and the article, thereby providing increased force at lower localised pressure. To this end, rather than using a pinhole-type nozzle, an elongated port may be used to generate a curtain of fluid. Such an arrangement is beneficial in that it provides the increased surface area but still provides good directional control. However, other nozzle arrangements are within the scope of the invention. For example, plural pinhole- type nozzles may work together on an article in parallel.

Preferably, the fluid is a gas such as air.

According to a fourth aspect, there is provided a controller for controlling the apparatus of the second aspect and/or the apparatus of the third aspect. Preferably, the controller is adapted to determine a position of an article and/or receive position information for an article and control actuation of the apparatus of the second and/or third aspect based at least in part thereon. As will be appreciated, where discrete carriers are used to convey articles, the position of an article may be derived based on a determined position of the respective carrier. According to one embodiment, the position of articles is detected as they move along a conveyor. The stream(s) may then be controlled based on a predicted path of the articles.

According to an alternative embodiment including the apparatus of the second aspect, the controller may be configured to vary one or more parameters of the stream(s) as the detected position of the article changes after it has been ejected from the conveyor. This may include which and the number of streams used. Preferably, the controller includes or is coupleable to a sensor for determining a position of an article or article carrier.

According to a fifth aspect of the invention, there is provided a system for processing articles, the system comprising: the apparatus of the second aspect; and/or the apparatus of the third aspect; and/or the controller of the fourth aspect.

While inclusion of an apparatus according to the third aspect is preferred, it is not essential. Other, more conventional means of ejection may be used such as a mechanical actuator that is used to impinge directly or indirectly on the articles. In the latter case, carriers used for the articles may be pivotally mounted with an actuator used to impinge on a portion of the carrier, thereby effecting said ejecting.

Preferably, the system includes conveying means for conveying the articles to whatever ejection means are used. Such conveying means may include discrete article carriers. Such carriers may be configured in a similar manner to those described in the aforementioned United States patent number 7,121,399 although the invention is not limited thereto. Thus, the conveyor means may comprise one or more pairs of rollers coupled to a conveyor belt, wherein the articles are arranged to sit substantially between one of the one or more pairs of rollers. Further conveying means may be provided to receive and convey the articles from their final destination (i.e., after having been deflected by the apparatus of the second aspect).

Again, the fluid may be a liquid, a gas or a mixture thereof. Preferably, the fluid comprises air or an air mixture. Preferably, the ejection means ejects an article from the conveyor means during and/or after the conveying and before, during and/or after the impinging.

Preferably, the one or more streams cause the article to decelerate in a first direction and/or accelerate in a second direction.

To ensure that articles arrive at their desired destination but do so in a limited amount of space, one or more of the streams may urge the articles downwards. As will be appreciated, this will tend to create a greater likelihood of damage to the articles and a balance between the likelihood of damage and the space requirements will need balancing for any particular system.

The system may comprise a physical curtain in addition to or as an alternative to the apparatus of the second aspect. When the two are used in combination, the physical curtain may be used to control the motion of articles not sufficiently controlled by the fluid propulsion means.

Preferably, the system is adapted to form part of an article grading or sorting system.

More preferably, the system is adapted to form part of a produce grading or sorting system.

More preferably, the system is adapted to form part of a fruit grading or sorting system.

Yet more preferably, the system is adapted to form part of a cherry or tomato grading or sorting system these such fruits being particularly susceptible to damage.

The invention further provides methods corresponding to the apparatus of the third aspect, the controller of the fourth aspect and the system of the fifth aspect.

Further aspects of the invention, which should be considered in all its novel aspects, will become apparent to those skilled in the art upon reading of the following description which provides at least one example of a practical application of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described by way of example, with reference to the accompanying drawings, in which:

Figures 1-5 are alternative views of an embodiment of the invention. More particularly, Figures 1-5 show front, plan, side, perspective and exploded views, respectively, of an embodiment of the invention.

Figures 6-8 and 10 broadly correspond to Figures 1-3 and 5, respectively, with additional detail and/or slight variations shown.

Figure 9 broadly corresponds to Figure 4 with Figure 9a showing additional detail of the Figure 9 embodiment. Further aspects of the invention, which should be considered in all its novel aspects, will become apparent to those skilled in the art upon reading the following description which provides at least one example of a practical application of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The embodiments shown in the Figures are configured for processing cherries. While the invention may be incorporated within cherry processing systems, the invention is not limited thereto and may be configured to process other types of articles, including non- foodstuff or produce articles. Further, modifications required to adapt these embodiments for other types of articles may be made without invention based on the teachings herein.

Referring to Figures 1 - 5, the apparatus 1 includes ejectors 2a and diverters 2b. As will be apparent to those skilled in the art, apparatus 1 may comprise any number of ejectors 2a and/or diverters 2b, depending on the particular application of the invention.

A conveyor 5 moves items 3 (e.g. fruit) along a first path. In the embodiments shown, this is a substantially straight path in the Z direction (see Figure 2). However alternative configurations may be used.

The conveyor includes a chain to which article carriers are connected. Each carrier includes two pairs of rollers 15 providing two processing lines, one either side of the chain. The rollers 15 are configured to receive the items of fruit therebetween as shown in the drawings.

The conveyor shown, including the chain and carrier, are provided by way of example only.

The ejectors 2a serve to remove the fruit 3 from the conveyor 5. According to the embodiment shown, the ejectors 2a include nozzles fluidly coupled (via conduit 4) to a fluid reservoir (not shown) that produces streams of the fluid that effect said ejection, urging the articles 3 in the direction of the arrows 7 (substantially in the X direction - see Figure 2). The subsequent motion of the articles 3 comprises a first component imparted by the conveyor 5 and a second imparted by the ejectors 2a.

Preferably, as shown, the ejectors are configured to expel a curtain of fluid, preferably air. Alternatively, a pinhole-type nozzle may be used or plural such nozzles may be used in parallel, forming an array, preferably a substantially linear array. While the particular fluid chosen may be selected according to system requirements, air is preferred due to the generally ready availability of compressed air in processing plants and the absence of any need to remove the fluid after it has been used to impart the desired motion.

The fluid curtain (or array) is preferably orientated substantially vertically but may be offset therefrom. For example, the fluid curtain may be inclined upwards along the conveyor 5 path, thereby better maintaining correlation between the fluid curtain and the fruit 3 as it is urged out of the carrier and along the conveyor 5.

Diverters 2b serve to control the motion (speed and/or direction) of the articles after ejection from the carriers. Diverters 2b urge the fruit in the direction 8 such that the trajectory of the fruit 3 conforms generally to arrows 14 (see Figures 2 and 3). In the embodiment shown, the fruit 3 is urged generally in the reverse direction to the conveyor 5 (thereby slowing the items down to prevent damage thereto) and also downwards so as to urge the fruit 3 to a desired destination over a shorter distance, reducing space requirements.

Each diverter 2b is shown as expelling a plurality of streams (see Figure 2), each stream being in the form of a fluid curtain orientated substantially vertically. While the streams are shown as being substantially parallel, they may be otherwise orientated. For example, the outermost nozzles may additionally urge the fruit 3 away from optional, physical curtain 6 which may be provided to capture fruit 3 that deviates from acceptable paths. While curtain 6 is shown as being a substantially rigid surround, it may be configured as a suspended curtain.

The streams expelled from the diverters 2b may be predetermined i.e., controlled based on a predicted path of the articles after they are ejected by ejectors 2a. According to one embodiment, the streams are adjustable at the system setup stage, enabling the stream(s) to be adjusted depending on the articles being processed and other system parameters which may change (e.g. conveyor 5 speed). Additionally or alternatively, the stream(s) may be adaptive based on a detected or predicted position of the articles after they leave the conveyor 5.

In the shown setup, arrows 10-13 show example adjustments that may be made, namely the angle of tilt about the X axis 10, the height 11, a distance along the Z axis 12 and the angle about the Y axis 13. The number and which ones of a plurality of streams may also be variable.

The streams of the ejectors 2a and/or the diverters 2b may operate continuously or in response to the detected presence of an article. According to one embodiment, the stream(s) of diverters 2b may be applied during conveying and/or at the point of ejection. The pressure of the stream(s) may begin at a low level during conveying, and subsequently increase.

The particular fluid ejection and diversion arrangement and fluid may be chosen in order to minimise the chance that the article, such as fruit 3, will be damaged but such that the force is sufficient to impart the desired motion. For example, if an arrangement with a high-pressure fluid and a small area of contact is chosen, then it may cause the fruit to be punctured. This is clearly undesirable. Consequently, the streams used are preferably configured depending on the articles being processed. In a preferred embodiment, the ejectors 2a and/or the diverters 2b include elongate ports that generate curtains of fluid i.e., a two dimensional stream. As will be appreciated, the ports may be other than linear and may, for example, be generally arcuate.

Ejectors 2a may alternatively comprise mechanical ejection means as described hereinbefore. For example, roller 15 may be tiltable with actuation of an actuator against a portion of the carrier or roller causing the roller to tilt and eject the fruit 3. Alternative implementations involving mechanical ejection means may also be used.

Any one or more of the pressure, duration, direction, timing and area of contact of the streams of ejectors 2a and/or diverters 2b may be controllable, as desired. In a preferred embodiment, one or more of the pressure, duration, direction, timing and area of contact of the ejection is controlled to ensure that the fruit 3 is not bruised or otherwise damaged, as well as to control the motion of the articles in the desired manner (i.e., such that they arrive at a desired destination and travel along a preferred trajectory).

Additional diverters may be provided as desired. For example, relatively low pressure streams may provide a cushioning bed for the surface on to which the articles are destined. Alternatively, physical cushioning such as foam may be provided, as required.

Figure 6 broadly corresponds to Figure 1 with some elements removed to aid clarity.

Figure 7 broadly corresponds to Figure 2. Notably, the deflectors are shown in a different orientation.

Figure 8 corresponds to Figure 3 with additional detail shown for the deflectors. Figures 9 shows a configuration similar to that of Figure 4. Figure 9a shows additional detail of the Figure 9 arrangment. More particularly, in this embodiment, ejector 2a is in the form of 4 spaced apart pinhole-type apertures which are connected to a fluid supply via passages formed inside the main body of the supporting structure. Other arrangements may of course provide the same result. For example, 4 separate nozzles could be coupled to a framework and a fluid supply.

Figure 10 shows a configuration similar to that of Figure 5. By way of example, for a system configured to process cherries of a size range of approximately 20 to 35 mm, a fluid curtain-type ejector nozzle may have a length of between 15 and 20 mm, and a width of approximately 0.25 mm. In the same system, the diverter may have a length of 50 to 60 mm and a width of approximately 0.25 mm.

Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising", and the like, are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense, that is to say, in the sense of "including, but not limited to".

The entire disclosures of all applications, patents and publications cited above and below, if any, are herein incorporated by reference. Reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that that prior art forms part of the common general knowledge in the field of endeavour in any country in the world.

The invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, in any or all combinations of two or more of said parts, elements or features.

Wherein the foregoing description reference has been made to integers or components having known equivalents thereof, those integers are herein incorporated as if individually set forth.

It should be noted that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the invention and without diminishing its attendant advantages. It is therefore intended that such changes and modifications be included within the scope of the invention.

Claims

1. A method for diverting an article moving in a first trajectory, the method comprising: impinging or substantially impinging the article with one or more fluid streams so as to control the motion of the article.

2. The method of claim 1, wherein the one or more streams adjust the first trajectory to a second trajectory.

3. The method of claim 2, wherein the adjusting directs the article towards a desired destination.

4. The method of claim 2 or claim 3, wherein the adjusting is controlled to prevent or reduce damage to the article by the one or more streams and/or resulting from impact against a surface.

5. The method of any one of the preceding claims, comprising conveying the article on prior to the impinging.

6. The method of claim 5, comprising ejecting the article during and/or after the conveying.

7. The method of any one of the preceding claims, comprising ejecting the article before, during and/or after the impinging.

8. The method of any one of the preceding claims, comprising controlling any one or more of the pressure, duration, direction, timing and area of contact of at least one of the one or more streams.

9. The method of claim 8, wherein said controlling is, at least in part, predetermined based on a predicted position or trajectory of the article.

10. The method of claim 8 or claim 9, wherein the controlling is, at least in part, based on a detected position of the article.

11. The method of any one of the preceding claims, comprising varying the force and/or direction thereof applied to the articles by the one or more streams.

12. An apparatus for diverting an article moving in a first trajectory, the apparatus comprising: means for impinging or substantially impinging the article with one or more fluid streams so as to control the motion of the article.

13. The apparatus of claim 12, wherein the means for impinging comprises fluid propulsion means.

14. The apparatus of claim 12 or claim 13, wherein the means for impinging is adapted to be controlled to prevent or reduce damage to an article.

15. The apparatus of any one of claims 12 to 14, comprising or coupleable to control means for controlling the means for impinging.

16. The apparatus of claim 15, wherein the control means is configured to control any one or more of the pressure, duration, direction, timing and area of contact of at least one of the one or more streams.

17. A controller for controlling the means for impinging of the apparatus of any one of claims 12 to 16.

18. The controller of claim 17, adapted to determine a position of an article and/or receive position information for an article.

19. The controller of claim 17 or claim 18, adapted to control said means for impinging based, at least in part, on a position of the article.

20. The controller of any one of claims 17 to 19, configured to vary one or more parameters of the stream(s) as the detected position of the article changes.

21. The controller of any one of claims 17 to 20, comprising or coupleable to a sensor for directly or indirectly determining a position of an article.

22. A system for processing articles, the system comprising: the apparatus of any one of claims 12 to 16; and/or the controller of any one of claims 17 to 21.

23. The system of claim 22, adapted to form part of an article grading or sorting system.

24. The system of claim 23, wherein said articles are live produce such as fruit.

25. A method substantially as hereinbefore described with reference to any one of the embodiments shown in the drawings.

26. An apparatus for diverting an article moving in a first trajectory substantially as hereinbefore described with reference to any one of the embodiments shown in the drawings.

27. A controller substantially as hereinbefore described with reference to any one of the embodiments shown in the drawings.

28. A system substantially as hereinbefore described with reference to any one of the embodiments shown in the drawings.