GB2432356A

GB2432356A - Chute for material handling

Info

Publication number: GB2432356A
Application number: GB0623013A
Authority: GB
Inventors: Richard Larrington
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-11-21
Filing date: 2006-11-20
Publication date: 2007-05-23
Anticipated expiration: 2026-11-20
Also published as: GB0623013D0; GB2432356B; GB0523622D0

Abstract

Apparatus for controlling the movement of material through a material delivery chute (17) in two stages, including tie bars/rods or like means (54) for producing an initial tapering of the chute (17) from the material inlet thereof to a first level downstream of the inlet so as partially to close the chute to material flow and to offset bulging of the chute as this level, and resiliently loaded elongate pressure members (23) located at a second level downstream of the first level cried by support means (29, 51, 52) and arranged to be displaced against the resilient loading thereof when the weight/volume of the material introduced into the chute attains a predetermined value, the support means for externally supporting each such the pressure members being is located one at each end of the support means (28) which are effectively interconnected by the tie rods/bars 54.

Description

-1-2432356

MATERIAL HANDLING

FIELD OF THE INVENTION

This invention relates to the handling of materials in divided andlor particulate form.

BACKGROUND TO THE INVENTION

It is known to provide chutes for guiding material from a first level to a lower level.

It is known to use guide chutes for controlling the flow direction of an uncontrolled flow of materials in divided form, such as waste materials arising from building maintenance activities, from a first level to a lower level mto, for example, a waste material receiving container.

It is also known to make use of material guide chutes for the purposes of handling materials such as root crops andlor tree grown fruit crops which are prone to being damaged during the course of handling.

1 5 Before discussing an embodiment of apparatus incorporating the concepts of the invention and particularly intended for use in the harvesting of root crops such as potatoes, carrots or other such crops andJor during the handling of fruit such as apples, pears, etc., it is convenient to note that whilst such crops are to all intents and purposes firm and solid physically to handle as compared with crops such as plums, etc., this can readily obscure the fact that the handling of firm and solid crops, in practice, invariably also carries the risk of bruising and other damage arising from items of a crop during handling excessively knocking one against the other or hitting a hard surface such as the bottom or side walls of a container into which the crops are being introduced for what ever reason such as packing, transferring crops from one container to another.

With present day methods of commercial harvesting of crops such as potatoes carrots the commercial requirement is for large quantities of the crop to be rapidly harvested, and at the time of harvesting with the capability of feeding the harvested crop into a bulk container for onward transmission from the location of harvesting.

Historically, a conventional method of feeding large quantities of a crop such as potatoes into transport containers accepting a filling weight of, for example, one ton weight involves the use of an elevator/conveyer system which transfers the harvested potatoes from the delivery end of a potato harvesting machine which is caused to travel simultaneously length ways of several rows of potato plants to lift and to remove the lifted potatoes from the unwanted material, namely any accompanying soil, leaves and stems, and then to feed the thus harvested potatoes 1 5 separated from the unwanted material onto a conveyor which in turn lifts he potatoes above the side walls of a container, i.e., lorry/trailer which is moving along the field in synchronism with the advance of the potato harvester.

This conveyor conventionally is positioned so that its material delivery end clears the side walls of the container and as a result is positioned at such height that the potatoes need to free fall a considerable distance from the delivery end of the conveyor into the lorry trailer load receiving container etc. By reason of the extent of such free fall required to allow access to the interior of the container, the potatoes delivered at the start of a filling operation considerable free fall and are thus are thus likely to impact against the container floor and walls and also against previously deposited potatoes with considerable force thereby creating the real hazard of bruising the potatoes and/or otherwise damaging the potatoes.

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As is well understood, such damage can lead to ingress of fungi spores etc., with the consequential enhanced risk of initiating conditions for subsequent rotting of the potatoes.

In our co-pending Application No 0419131.8 we have disclosed arrangements for reducing the effects of such free fall conditions when handling material in particulate andlor divided form from a supply position to a receiving container by a material delivery system by applying impact cushioning materials,i.e., a plastics cellular sponge material to each rigid part of the apparatus likely to be contacted by falling material during the delivery thereof and additionally covering the impact cushioning material by a flexible covering material presenting a non-abrasive surface i.e., PVC plastics material to said cushioning material.

OBJECTS OF THE INVENTION

It is an object of the invention to facilitate the avoidance of damage such as above mentioned.

1 5 It is a particular object of the invention to provide means for facilitating the avoidance of damage to a flow of produce, crops or the like through a delivery chute between the location of the delivery of the material to the chute and the material discharge outlet of the chute.

STATEMENTS OF TI-fE INVENTION

Broadly, according to a first aspect of the invention there is provided a method of controlling the flow of material through a tubular chute including the step of producing an initial shaping to the chute at a first level downstream of the level of material entry to the chute, and means located at a second level downstream of the first level for exerting external closure pressure upon the chute in such manner

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selectively to vary the cross-section of the chute available for material to travel through the chute downstream of said second level...

Preferably the control of the flow of material through the a flexible guide is in response to the weightivolume of material delivered to the flexible guide, the arrangement being such that the material is constrained/prevented from being discharged from the flexible guide until the weight of the material attains a predetermined amount.

In a preferred construction means are provided at said first level for inwardly displacing opposed walls with respect to the inlet of the chute so as to produce an initial tapering of the chute part leading towards said first level.

In a preferred construction a the side walls of the chute at said first level are constrained from bulging outwards as the result of the presence of said material.

Preferably the means for moving the chute walls towards each other at said second level includes resiliently loaded pressure members that are caused to be 1 displaced against the resilient loading thereof when the weight of the material introduced into the chute attains a predetermined weight.

In a preferred construction the means at said second level for moving the chute walls towards each other includes a pair of rolls/rollers arranged to bear upon said opposed walls.

In further construction the means for moving the chute walls can include resiliently loaded pressure pads.

A still further aspect of the invention there is provide apparatus for controlling the movement of material delivery chute including means for producing an initial tapering of the chute from the material inlet thereof to a first level downstream of the inlet so as partially to close the chute to material flow and to offset bulging of the chute at this level, and resiliently loaded elongate pressure members located at a second level downstream of the first level carried by support means and arranged to be displaced against the resilient loading thereot when the weight/volume of the material introduced into the chute attains a predetermined weigthlvolume value, the means for supporting each pressure member being 1 0 located one at each end of a chute, and wherein the support means are effectively interconnected by tie rods or the like at said first level..

BRIEF DESCRIPTION OF TI-FE DRAWFNGS

For a better understanding of the invention reference will now be made to the accompanying drawings in which:- 1.5 Figure 1 is a schematic part front part side view from above of a trailer mounting a plurality of units incorporating the concepts of the invention; and Figure 2 very schematically illustrates to an enlarged scale a detail of the apparatus of Figure I.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring now to Figure 1 the apparatus incorporating the concepts of the present invention is intended amongst other possibilities to be usable in conjunction with a flat top trailer or the like as is commonly used for agricultural/horticultural purposes. Thus Figure 1 of the drawings very schematically show at I a trailer comprising a chassis 2 supporting a load receiving platform 3 and mounted from road running wheels 4. The chassis 2 is provided with appropriate towing bar or like facilities 5 for attachment to a towing vehicle (not shown). Conventionally such trailers I are constructed according to generally standard dimensions related to the primary intended usage function of the trailer and to the carrying capacity normally intended for such general use. In relation to trailers particularly suitable for transportation of harvested crops the load receiving platform 3 can be in the form of a flat top with shallow side rails and/or side panel facilities (not shown).

The platform is dimensioned so as to be able to mount a plurality of standard sized individual containers 6. Two such containers 6 are shown in Figure 1 in dashed lines. In practice, depending upon trailer size two, four, six to eight or more separate containers 6 of a size or sizes as commonly utilised in the handing crops of the kind above mentioned may be provided.

In use, in the arrangement illustrated the containers 6 are required to be merely 1 5 placed upon the trailer platform 3 for the purposes of filling and then to be subsequently transferred to a location at which the containers are removed from the trailer I for subsequent handling and to be replaced by a further batch of empty containers for subsequent filling.

Whilst apparatus incorporating the concepts of the invention illustrated is intended to be mountable to the trailer in the manner of an attachment for the trailer the apparatus of the invention can be used in conjunction with two or more trailers and, for example, transferred from one trailer to another whilst the trailers are in the field' thereby allowing a continuous movement of trailers with fIed containers from the filed whilst crop harvesting continues.

The apparatus 7 for controlling the feed of a crop into a container 6 is very schematically illustrated in the Figure 1 when placed upon the flat top trailer I and in more detail in the Figure 3 The apparatus 7 includes a support frame section 8 that is intended to rest upon the trailer platform 3 and a schematically represented crop cushioning framework section 9 that is mounted from the support frame section 8 in such manner as to he vertically displaceable between a lowered position and a fully raised position as vill be discussed hereinafter. For this purpose the section 8 has associated therewith a number of vertical posts 11 located one at each end of the corners of the apparatus In the Figure I four such posts are illustrated. These posts II serve to mount means 12 for enabling the lifting and lowering of the cushioning framework section 9. The lifling and lowering arrangements can be mechanical or hydraulic. In the latter case the hydraulic power take off of a towing tractor may be utilised. The Figure I illustrates a lowered setting for the cushioning framework section 9.

The cushioning Framework section 9 incorporates longitudinally directed side rails 13 and a central longitudinal rail 14, together with end and intermediate transverse rails I 5. These rails effectively define, depending upon the number of these transverse rails 15, a number of rectangular frameworks (one for each container 6). All of these rails 13, 14 and 15 are covered with cushioning material whose purpose is to reduce as much as possible the risk of damage to any falling material i.e., root crop, from being damaged as result of striking the cushioning framework section 9. The upper part of the cushioning framework section 9 is surrounded by a protective fencing/frame 16.

In addition, each such cushioned rectangular framework section 9 serves to mount a rectangular cross section material delivery chute 17 formed from a flexible plastics material. The Figure 1 illustrates the provision of eight such chutes 17 The inlet 18 to the chute 17 in practice connects with the associated rails of the cushioning framework section 9. The length of the chute is such that the discharge end 19 of chute 17 can reach down closely to the trailer floor and thus close to the bottom of any container 6.

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Since it is required according to the invention to be able selectively to control flow of material through the chutes 17 provision is made for the cross sectional area of each chute to be selectively reduced for the purposes of restricting material flow in a controlled manner.

In the embodiment this control is achieved by what can conveniently termed a two stage chute tapering process in which an initial tapering of the chute is produced by the provision of tie bars/rods 54 or their equivalent extending along the opposite side walls of the chute 17 at a first level located below the level at which the material being conveyed enters the chutes 1 7 These tie bars/rods 54 are supported by frame members 29,5 1,53 that are in turn supported from the of the framework portions 15 of the cushioning framework 9 associated with the the chute with which the tie rods are associated.

At a second level of the chute downstream of the tie bars/rods 54 or the like there is provided arrangements for enabling selective/restricted displacement of 1 5 opposed walls of each chute 1 7 between the first and second levels towards and away from each other As will be understood the moving the chute walls closer to each other reduces the chute cross section available for the passage of crop material through the chute and by enabling the walls to move away from each other, i.e., return to their rest positions increases the cross sectional area. and thus crop throughput capability.

In the embodiment shown the longitudinally directed walls 21 and 22 of the chute 17 are arranged to be displaced relative to each other by means of cushioned rolls/rollers 23 that are carried by axles 24 that are parallel to the tie bars/rods 54 and are supported at each end by one end of an arm 25 whose other end 26 is 2 5 pivotally mounted to the end 27 of an associated tie bar/rod 54 that is connected with an arm 28 that is mounted to a support bracket 29. (located centrally of the associated end region of the chute 23) whose upper end 52 connects with a bracket 51 connecting at 53 with a member 55 that facilitates its connection with the cushioning frame 9 Ii will be noted that with this arrangement the axes of the rolls swings/pivots about the longitudinal axes of the associated tie bars.

With the above arrangement it has been found that by locating the first and second levels close together the difference in diameter between that of the tie bars and that of the resiliently loaded rolls 23 a change of inclination is produced in the chute which provides a narrow platform like area that acts in such manner as to slow and turn crops such as carrots in such manner as to assist in preventing them from bridging' the interior of the chute and thus cause blockage.

The provision of the tie bars/rods 54 or their equivalent has a practical function of considerable importance.

In practice, when crops such as potatoes are to be dropped into the chutes they fall onto onto a so-called fall breaker (not shown) that is provided in each chute for such crops at the mouth region of each chute, the fall breaker being centrally positioned and extending lengthways of the mouth of the chute. The provision of the fall breaker reduces the available throughput space at the mouth of the chute.

This in practice ensures that free fall of the crop through the chute is prevented sincc the crop contacts the fall breaker on its entry into the chute thereby ensuring that when feeding crops such as potatoes and the rolls are in an opened setting it is not possible for the crop to free fall straight through the chute into the container 6 associated therewith and thus be likely to be bruised as as result of any such free fall.

When however crops that tend to by sticky' when harvested and/or are elongate nature such as carrots, are being fed into the chutes it has been found advantageous to remove the central fall breaker to avoid/reduce the risk that the falling crop chokes the inlet regions to the chute. This choking of the upper

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regions of the chutes leads to a bulking-up effect that causes the chute to bell outwards immediately above the pressure rolls and in so doing pulls/lifts the regions of the chute 17 that should be below the pressure rolls 23 upwards thereby enabling a quantity of any crop involved to accumulate above the rolls 23 and possibly result in a total blockage of the chute.

It has been found that the provision of the tie bars or their equivalent prevents such bulking-up and consequential upwards lifting of the chute. It will be noted that with the arrangement illustrated that this displacement of the walls 2 I and 22 effectively lifts the discharge end 19 of the chute 1 7 upwards.

This prevention of this possibility thus forms said important function of the provision of the tie bars/rods 54.

A further consequence of the provision of the tie bars/rods is Ihat the generally rectangular shape of the chute is maintained downwards of the chute The resilient loading of the rolls/rollers 23 is such that they are moved into a rest 1 5 position/setting. That is to say the rest position of the rolls/rollers 23 is such as to prevent material introduced into the chute 15 from immediate free fall through the chute 17 In other words when the chute is empty the walls 21 and 22 are effectively closed together in a position just below the cushioning rail 20 and can be regarded as serving as a cushioned break fall rail function whereby any crop or other material fed into the chute 17 builds up at this point and travels outwardly to move into contact with the chute walls 21 and 22.

The resilient loading of the rolls 23 can be by way of torsion springs located at the pivotal connection of the arms 28 and 26 or by any other convenient means of resiliently loading the roll/roller carrying arms.

In a further possibility not shown the positioning of the rolls/rollers can be by way of a hydraulic/pneumatic system involving appropriate rams to control the required settings of the rams selectively to vary the cross section of the chutes.

In use when material is introduced by way of, for example a conveyor arrangement, into the chutes. The material falls into the upper part i.e., mouth region 18 of the chute 1 7 and in view of the rest setting of the rolls 23, 24 the chute 17 is initially closed to material travel through the chute. As material continues to fall into the chute inlet 18 it accumulates above the region of the roll/rollers 23 until a predetermined weight of the material has been deposited. A suitable weight of root crop can be 25 Kilos of weight. However, it will be appreciated that the weight value involved would be related, for example, to the nature of the crop involved and the specific requirements for rates of loading Once this weight has been reached the weight of deposited material/crop pushes the rolls 23 apart thereby enabling material in the chute to commence moving 1 5 further down the chute. In practice as the rolls 23 start to move apart initially a trickle/flow of the crop passes through the rolls region of the chute and thus through the opening formed between the chute sides 21 and 22. to descend through the chute 17 into the associated container 6. In practice, it has been found that the material/crop tends to hug the side walls 21 and 22 of the chutes. 20. .

material/crop flow continues so long as the crop weight remains above that at which the chute walls are caused to move away from each other.

By reason of the mode of closing the chute 17 the downward pressure exerted by the falling material will progressively open the lower regions of the chute i.e., beneath the rolls/rollers 23 whereby the material is gently delivered into the associated container 6.

Once the flow has started the ongoing steady delivery of material to the chute tends to maintain a steady crop material flow. -1 2-

As more material enters the container a cone or pyramidal mound builds up towards/above the rolls region of the chute 17.

As more and more material is deposited into the chute the rolls/rollers 23 are progressively separated (in relation to crop material weight within the upper regions of the chutes) to increase the material flow path and the same time that the cushioning frame section 9 carrying the chutes and rolls/rollers is progressively raised vertically to lift the bottom 19 of the chute higher and higher with respect to the containers 6.

When the container has been sufficiently filled the supply of material from the 1 elevator/conveyor is stopped whereby the rolls/rollers 23 will automatically return the chute walls 21, 22 towards each other to their closing rest positions.

Whilst the forgoing description has disclosed the use of rolls/rollers it will be appreciated that other forms of means for controlling the movement of the chute walls relative to each other. For example, appropriately profiled pressure exerting 1 5 boards, pads or the like could be used It will be understood that whilst the specific description has been directed to an embodiment of apparatus incorporating the concepts of the invention the apparatus can take various forms in terms of the construction of the chute, its supporting arrangements and the mode of externally pressing the chute walls towards each other so as to reduce and/or shut off flow of material through the chute.

Whilst the above descried embodiments have involved the use of resiliently loaded gripper arrangements that rely upon response to the weight of material within a guide chute it will be understood that other means of controlling the operation of the gripper arrangements may be used.

For example, each gripper arrangement can be controlled by means of a hydraulic or pneumatic control system in which appropriate rams are used to displace the grippers in a required sense.

Whilst such arrangements can readily be arranged to respond to the weight of material within the guide chutes the use of such alternative systems makes it readily possible to provided for additional or alternative control operation facility.

For example, the control system for a hydraulic/pneumatic system could be controlled from any convenient location. For instance in the case of the gripper arrangements disclosed in Figure 1, the controls for the hydraulic arrangements be located within easy access of the driver of a vehicle, i.e., tractor and such that the grippers associated with the trailer could be separately operated and when required to be used..

In practice, he operation of such control arrangements can additionally involve a facility of visual examination of the content of material within a guide chute 1 5 enabling an operator to actuate a gripper operating arrangement as and when considered necessary following a visual inspection.

Furthermore, in addition to or as alternatives to the reliance upon the weight of material present within the guide chute as a basis for controlling the operation operation of the grippers as has been discussed it will be appreciated other modes of monitoring the conditions within the guide chutes could be used. For example, detection of the level of material within a chute could be used.

A convenient mode of level detection could involve the use of optical sensors connected to operate the controls for actuating the arrangements for operating the grippers.

Claims

CLAIMS

I. Apparatus for controlling the flow of material through a tubular chute including the step of producing an initial shaping to the chute at a first level downstream of the level of material entry to the chute, and means located at a second level downstream of the first level for exerting external closure pressure upon the chute in such manner selectively to vary the cross-section of the chute available for material to travel through the chute downstream of said second level..

2. Apparatus as claimed in claim 1, and wherein the control of the flow of material through the a flexible guide is effected in response to the weight/volume 1 0 of material delivered to the flexible guide, the arrangement being such that the material is constrained/prevented from being discharged from the flexible guide until the weight of the material attains a predetermined amount.

3. Apparatus claimed in claim I or 2, and wherein means are provided at said first level for inwardly displacing opposed walls with respect to the inlet of the 1 5 chute so as to produce an initial tapering of the chute part leading towards said first level.

4. Apparatus as claimed in claim 1,2 or 3, and wherein the means for moving the chute walls towards each other at said second level includes resiliently loaded pressure members that are caused to be displaced against the resilient loading thereof when the weight of the material introduced into the chute attains a predetermined weight.

5. Apparatus as claimed in claim 4, and wherein the means at said second level for moving the chute walls towards each other includes a pair of rolls/rollers arranged to bear upon said opposed walls.

6. Apparatus for controlling the movement of material through a material delivery chute, including tie bars/rods or like means for producing an initial tapering of the chute from the material inlet thereof to a first level downstream of the inlet so as partially to close the chute to material flow and to offset bulging of the chute as this level, and resiliently loaded elongate pressure members located at a second level downstream of the first level carried by support means and arranged to be displaced against the resilient loading thereof' when the weight/volume of the material introduced into the chute attains a predetermined weight/volume value, the support means for externally supporting each pressure members.being located one at each end of the chute, and wherein the support means are effectively interconnected by tie rods/bars or the like at said first level..

7. Apparatus for controlling he movement through a material delivery chute, constructed and arranged to operate substantially as herein before described with 1 5 reference to the accompanying drawings.