WO2006120706A1

WO2006120706A1 - Gap width adjustment mechanism for the belts for grading system

Info

Publication number: WO2006120706A1
Application number: PCT/IS2006/000010
Authority: WO
Inventors: Ragnar Magnusson; Egill Thor Ragnarsson
Original assignee: Style Ehf.
Priority date: 2005-05-13
Filing date: 2006-05-15
Publication date: 2006-11-16

Abstract

The present invention relates to an apparatus and a method for grading sensitive products. The apparatus and a method treat the objects to be graded gently and is accurate and may be constructed so as to handle extremely large quantities. The grading device of the present invention has grading channels that are wider at the outlet than at the intake. The belt machine draws the objects forward between two inclined belts which form the channel. An adjusting device is implemented perpendicular underneath the belts of the apparatus comprising alternatively arranged support members (10) and adjusting members (12) arranged on an adjusting screwing shaft (11) . Both components comprise screwing sections (13 , 18) which regulates an increase or a decrease in the gap between the support members (10) when the adjusting screwing shaft (11) is rotated.

Description

GAP WIDTH ADJUSTMENT MECHANISM FOR GRADING SYSTEMS

Field of invention

The present invention relates grading systems for grading objects, based on conveyor equipment with ridge-belts. The device and the method make possible to adjust the gap width of such grading systems more precisely and accurately than current technology allows.

Background) The process of grading objects such as small and delicate marine species or fruit can be a problem due to their small size and the volume to be processed at each time and the fact that the quality of the food items deteriorates quickly upon rough handling procedures. An efficient grading process is therefore required based on selection criteria such as size and/or the sex.

Several different types of grading devices are known for grading fish and food items, which grade the items according to an assessment of their thickness. The known devices are based on belts and rollers as well as shaker-graders, which use several grading channels.

WO9641541 discloses a grading device based on specially-designed conveyor equipment so-called ridge-belts, which move the objects forwards without shaking or rubbing the items during the grading process. Such grading devices are designed so that the grading channels are narrower at the in-feed end (receiving end) than at the outlet end. This device allows for more gentle treatment of the objects to be graded, with a high processing rate. The problem solved by using this grading device is that the material is arranged into a single layer in optimal position onto the grading apparatus. This ensures that small items are not carried on top of larger items into a wrong grading compartment.

The adjustment of the channel width both at the intake and the outlet end is an important aspect of this technology. The channel width is set before the grading process is started, but sometimes the channel width needs to be adjusted or fine-tuned during the grading process. This requires a solution, where the channel width can be set before and during the grading process in a manner such that the channel width is the same between in all the channels on the grading device.

The present invention provides a new and more efficient solution to set and adjust or fine-tune the channel width of ridge-belts of grading devices in a more precise and accurate manner.

Summary of the invention

The present invention relates to grading devices, which treat the objects to be graded gently, is accurate and may be constructed so as to handle extremely large quantities. The grading device of the present invention has grading channels that are wider at the outlet than at the intake. The belt machine draws the objects forward between two inclined belts which form the channel, and if more channels are included in the same machine, each additional channel consists of an independent unit, i.e. another machine which is placed next to the first one. The machine takes the form of a conveyor belt which neither shakes the objects nor rubs them in the course of moving them, but moves them gently forward until the point where the gap becomes large enough for the object to fall through it.

In the first aspect of the present invention an apparatus for grading sensitive products, comprising:

- an in-feed device,

- grading unit and - receiving unit,

The grading unit comprises the following components:

1. A plurality of endless ridge-belts arranged side by side and moved continuously in a forward direction, forming a gap there in-between, the gap being increased in the direction of movement, two adjacent belts receiving, conveying and releasing the products as the gap there between becomes grater than the product thickness into the receiving units, the ridge-belts being longitudinally supported by plurality of guide rails. 2. An adjusting device is arranged underneath the ridge-belts and supporting guide rails, the adjusting device arranged for adjusting the distance between the ridge- belts, the adjusting device comprising: a) a plurality of support members, arranged in line, perpendicular underneath and corresponding to and supporting the guide rails, the support members. The support member further comprises a first screwing section, the first screwing section being a double action inner elevated portion of a cylinder forming a screw tread structure extending from the centre of the cylinder and towards each opening, b) a plurality of adjusting screwing members, arranged in line, perpendicular underneath the guide rails between the support members. The adjusting screwing member further comprises a second screwing section being a double action outer elevated portion of a cylinder forming a screw tread structure extending from the centre of the cylinder and towards each end and an inner hollow structure providing a grip for a penetrating object adapted to rotate the adjusting screwing member, and c) adjusting screwing shaft, penetrating the adjusting screwing member having a shape fitting the circumference of the inner hollow structure of the adjusting screwing member. Adjusting screwing members and support members are alternatively lined up underneath the guide rails. The second screwing member interacts with the first screwing section of the support members upon rotation of the adjusting screwing shaft in a manner increasing or decreasing the distance between adjacent support members and thereby the guide rails and the rigid belts.

The grading device as such is disclosed in WO96415, and will not be discussed in detail herein.

The adjusting device of the present invention relates to adjusting screwing members and support members being alternatively lined up on an adjusting screwing shaft. Both the adjusting screwing members and support members have counter fitting screwing sections and pressure means are placed on each end of the adjusting screwing shaft.

The support members of the present invention relate to items, which support the guide rails as they pass the upper part of the grading device. The support member comprises a screwing section, which will receive a counter fitting screwing section of an adjusting screwing member. The screwing section in the embodiment shown in figure 2 is a cylindrical like member as disclosed above. The support member further comprises a guide section, which secures the support member in an upright, vertical position in order to hold up the guide rails and receiving section for receiving the guide rails. The guide section can be two flat parallel pieces (as shown in figure 2) extending downwards from the screwing section forming a space to fit around a guide bar extending parallel to the adjusting device. The guide section can also be a hollow piece having an inner shape being circular, oval, triangular, square, hexagonal etc, which a holding bar can be put through to maintain the upright position of the support member. The receiving section of the support member is designed to fit into the lower section of the guide rails. In the embodiment shown in figure 3 the lower section of the guide rails is V-shaped, and thus the receiving section of the support member has a narrow triangular or conical shape.

The adjusting device of the present invention may comprise a control device attached to the adjusting screwing shaft adapted for turning the adjusting screwing shaft and thereby increasing or decreasing the gap between the ridged belts. The control device can be a manual member such as a steering wheel, winch or the like, or it can be a motor.

The pressure means of the present invention relate to means placed on each end of the adjusting screwing shaft, which are adapted for applying pressure on the support members and the adjusting screwing members of the adjusting device from both sides. By applying pressure on the row of adjusting screwing members and support members, a rotation of the adjusting screwing shaft will allow the adjusting screwing members to either push the support members apart or together. The pressure can be applied by means of a coil spring or a spiral as well as an electrical jack or a hydraulic jack. The grading gap interval is thereby altered by the width of the adjusting screwing members and the width of the ridge-belts.

In a second aspect of the present invention a method for adjusting the gap width between ridge-belts of a grading device is provided. The grading device comprises:

- an in-feed device,

- grading unit and

- receiving unit,

The grading unit comprises the following components:

1. A plurality of endless ridge-belts arranged side by side and moved continuously in a forward direction, forming a gap there in-between, the gap being increased in the direction of movement, two adjacent belts receiving, conveying and releasing the products as the gap there between becomes grater than the product thickness into the receiving units, the ridge-belts being longitudinally supported by plurality of guide rails.

2. An adjusting device arranged underneath the ridge-belts and supporting guide rails, the adjusting device is arranged for adjusting the distance between the ridge-belts, the adjusting device comprises: a) a plurality of support members, arranged in line, perpendicular underneath and corresponding to and supporting the guide rails, the support members. The support members further comprises a first screwing section, the first screwing section being a double action inner elevated portion of a cylinder forming a screw tread structure extending from the centre of the cylinder and towards each opening, b) a plurality of adjusting screwing members, arranged in line, perpendicular underneath said guide rails between the support members. The adjusting screwing member further comprises a second screwing section being a double action outer elevated portion of a cylinder forming a screw tread structure extending from the centre of the cylinder and towards each end and an inner hollow structure providing a grip for a penetrating object adapted to rotate the adjusting screwing member, and c) adjusting screwing shaft, penetrating said adjusting screwing member having a shape fitting the circumference of the inner hollow structure of the adjusting screwing member.

The gap width between the ridge-belts is determined by the adjusting device in that first screwing section of the support member is adapted to fit second screwing section of the adjusting screwing member on each side of the adjusting screwing member, and pressure means on each end of the adjusting screwing shaft adapted for applying pressure on the adjusting device from both sides when the adjusting screwing shaft is rotated in a manner increasing or decreasing the distance between adjacent support members and thereby said guide rails and said rigid belts.

In an embodiment of the present invention one or more adjusting devices can be implemented on the grading apparatus, such as at the intake end and the outlet end of the grading apparatus. For example, one adjusting device can be placed at the intake end and another one in the middle of the device forming a small increase in gap width to the second adjusting device. A third adjusting device is then place at the outlet end of the grading apparatus with much larger gap width. This will allow for grading of smaller size objects into several categories and the a collection of larger objects into one or two categories.

A control device or control mechanism is implemented on the adjusting device, coupled or attached to the adjusting screwing shaft, so that when the shaft is turned, the gap width is evenly adjusted. A control mechanism may comprise components such as:

- pressure means, f. ex. an electrical jack or a hydraulic jack - a motor, and

- a control board.

The gap size is then set by using the control board, which can be a simple electrical control board attached to the grading device, having control buttons which rotate the adjusting screwing shaft in each direction as well as controlling the speed of the grading device and the in-feed device. The control board can further be a wireless remote control or an industrial computer, which co-ordinates the turning of the adjusting screwing shaft by the motor and the pressure applied by the pressure means.

The shape of the adjusting screwing shaft and the corresponding circumference of the inner surface of the adjusting screwing member can be of any shape such as, but not limited to triangular, square, pentagonal etc.

An adjustment device as disclosed here is implemented on the in-feed end as well as on the outlet end of the grading device and as they are individually controlled, the gap width of each end can be altered without affecting the other.

Description of drawings The present invention will be further described with reference to the drawings using reference numbers in the drawings to identify the individual components of the invention.

Fig 1. A) A side view of the equipment designed for the grading of smaller fish species and relatively light objects. B) Top view of the same equipment.

Fig 2. Shows the individual components of the adjusting means of the present invention.

Fig 3. Shows the support of the guide rails on the support members.

Fig 4. Showing the mechanism for setting the gap-width on the in-feed and the oulet end of the grading device.

Fig 5. Showing top, bottom and side views of the support member.

Detailed description of the present invention

FIG. 1 shows a side-view of the grading device (1). (A) The objects to be graded are placed onto an in-feed device (step-channel) (4). As the objects slide downwards, they assume the optimal position before sliding onto the ridge-belts (3). If the objects are not adversely affected by contact with water, a water-pipe (5) is used to direct a film of water onto the step-channel, which makes the objects quicker to assume the optimal position. The gradient of the step-channel (4) is set so that the speed of the objects as they enter the grading gaps is as close as possible to the speed of the ridge-belts. The ridge- belts (3) run along guide-rails (2) and the guide-rails (2) rest on the adjusting device (9) attached to an adjusting screwing shaft. The number of ridge-belts may be from 2 to over 30 according to the processing rate required of the grader. The guides are shown with an upward incline in the figure, but they may be horizontal or inclined downwards, depending on what is found suitable at any given time. Between the ridge-belts (3) are formed the grading gaps, the number of which is one fewer than the number of ridge-belts. Below the ridge-belts (3) are cross- plates (22) for guiding and dividing graded objects between size categories.

The ridge-belts (3) as driven by the drive drum (6), frictional resistance between the drum and the belts being sufficient to drive the belts; if it is not sufficient, e.g. in the case of long machines or heavy items, then the drum is covered with object with a high friction resistance or with pins which engage in the ridges and so drive them. Drum (7) is a free drum which guides the belts into the guide slots in the belt guides.

(B) A light-construction grading machine seen from above, showing the motor (8) which drives the drive drum. It is desirable that the motor should be speed- adjustable, but whether it is a hydraulic motor or an electric motor is immaterial.

A gear motor may be used after the machine has been set and the object to be graded is always of the same type. The gap width on the in-feed end is narrower than on the outlet end. FIG. 2 discloses the individual components of the adjusting means of the present invention, a support member (10), a adjusting screwing shaft (11) and an adjusting screwing member (12).

Each support member (10) comprises a first screwing section (13), guide section (14) and receiving section (15). The first screwing section (13) has a cylindrical shape, where the inner surface comprises an elevated portion (16), which is an elevated portion forming a screw tread structure from the centre of the cylinder and towards each opening. The guide section (14) is attached to the cylindrical structure opposite to the receiving section (15) of the support member (10). The guide section (14) is shown here as two flat structures with a space between them in order to receive a guide bar. The receiving section (15) is adapted to fit into the slot of the lower part of the guide rail. In the embodiment shown in figure 2 the receiving section (15) is shown as a triangular or conical structure.

The adjusting screwing member (12) has a circular outer structure, where the inner surface (17) has a shape corresponding to the outer circumference of the adjusting screwing shaft (11), in order to fit onto the adjusting screwing shaft (11) as assembled. In the embodiment shown in fig. 2, the inner surface shape is hexagonal, corresponding to the shape of the adjusting screwing shaft of this particular embodiment. The circular outer structure of the adjusting screwing member (12) comprises a second screwing section (18), which is essentially an elevated portion having screw shaped form extending from the centre to each end of the circular structure.

In an embodiment of the present invention, the adjusting screwing member comprises a spacer in the central part of the member (between the screwing structures extending in each direction). By implementing a spacer in the adjusting screwing member, the size of the adjusting screwing member can be varied in order to alter the gap width intervals based on the type of objects to be graded.

The shape of the adjusting screwing shaft (11) and the corresponding circumference of the inner surface of the adjusting screwing member (12) can be of any shape such as, but not limited to triangular, square, pentagonal etc. In the embodiment shown in fig. 4, the shape of the adjusting screwing shaft (11) is hexagonal corresponding the shape of the inner surface if the adjusting screwing member (12). By using an inner circumference of a shape such as triangular, square, pentagonal and hexagonal, a grip is provided for a member (adjusting screwing shaft) so when the adjusting screwing shaft is rotated the adjusting screwing member is rotated or turned as well.

FIG. 3 shows the support of the ridge belts (3). The ridge-belts (3) run along guide-rails (2) and the guide-rails (2) rest on the support members (10) attached to the adjusting screwing shaft (11). There are slots in the bottom of the belt-guides, into which the support members (10) are inserted, the interval between the sides of the slots and the support members (10) being small. FIG. 4 outlines the mechanism for setting the gap-width on the in-feed and the outlet end of the grading device.

(A) The adjusting screwing members (12) are positioned on adjusting screwing shaft

(11) between the support members (10). The adjusting screwing members (12) are secured on the adjusting screwing shaft (11) due to the shape of the inner surface of the adjusting screwing members (12), corresponding the shape of the adjusting screwing shaft. Each screwing section (18) of the adjusting screwing member is adapted to fit into the first screwing section (13) of the support member (10), so that when the adjusting screwing shaft is turned the second screwing section (18) of the adjusting screwing member (12) is either screwed into or out of the support member (10) and thereby altering the distance between each two support members (10). One support member (10) is provided for each ridge belt and adjusting screwing member (12), is placed between each two support members (10), on the adjusting screwing shaft (11). Each side of the row comprising support members (10) and adjusting screwing members (12) is terminated with a support member (10). Outside the support member (10) is a pressure means. In this embodiment, the pressure mean is coil spring or a spiral (20) on each side. A control device (19) adapted to turn the adjusting screwing shaft (11) is positioned on one side of the adjusting screwing shaft (11) behind the coil spring. The second coil spring on the opposite end of the control device (19) is secured by any securing means (21) such as a pin, which may penetrate the adjusting screwing shaft. Pressure is applied on the adjustment device by coil spring or spiral (20) after the guide rails (1) on each end of the adjusting screwing shaft (11). The coil springs apply pressure on the adjustment device/means by their natural force. The support members (10), are adapted to be fastened to the upper surface of grading through the guide section (14) in order to maintain the receiving section (15) in a steady vertical position. Thereby, the support members (10) are only allowed lateral movements on the adjusting screwing shaft, whereas the adjusting screwing members (12) turn around the adjusting screwing shaft (11) as the adjusting screwing shaft is turned by the control device (19).

(B) As the adjusting screwing shaft (11) is turned in one direction the adjusting screwing members (12) pull the support members (10) together and the gap between them decreases. The adjusting screwing members (12) are shown as items with dotted outlines, which demonstrates that the adjusting screwing members (12) penetrate the support members (10) when they are the adjusting screwing shaft (11) is turned in this direction.

(C) When the adjusting screwing shaft (11) is turned in the opposite direction as compared to (B), the adjusting screwing members (12) push the support members (10) away from each other and the gap between them increases. FIG. 5 shows a top (sectional) view and a side view of the support member (10).

(A) Top view: A cylindrical member has the first screwing section as an elevated portion. The receiving section (15) extends in an opposite direction from the guide section (14), broad next to the screwing section but becoming narrow as it extends away from the screwing section. The guide section (14) is shown as two flat bars.

(B) Side view: The guide section (14) is shown as two bars attached to the cylindrical structure, adapted to be placed into gaps, holes or on each side of a bar, for securing the support member (10) in an upright position.

Claims

1. An apparatus for grading sensitive products, comprising:

- an in-feed device (4), - grading unit (1) and

- receiving unit,

said grading unit (1) comprising;

- plurality of endless ridge-belts (3) arranged side by side and moved continuously in a forward direction, forming a gap there in-between, the gap being increased in the direction of movement, two adjacent belts receiving, conveying and releasing the products as the gap there between becomes grater than the product thickness into said receiving units, the ridge-belts being longitudinally supported by plurality of guide rails (2), and

- adjusting device (9) arranged underneath said ridge-belts and supporting guide rails, said adjusting device (18) arranged for adjusting the distance between said ridge-belts, said adjusting device comprising;

- a plurality of support members (10), arranged in line, perpendicular underneath and corresponding to and supporting said guide rails (2) , said support members (10), having further an

- first screwing section (13), the first screwing section being an double action inner elevated portion of a cylinder forming a screw tread structure extending from the centre of the cylinder and towards each opening, and

- a plurality of adjusting screwing members (12), arranged in line, perpendicular underneath said guide rails (2) between the support members (10), said adjusting screwing member (12) having:

- a second screwing section (18) the second screwing section being an double action outer elevated portion (4) of a cylinder forming a screw tread structure extending from the centre of the cylinder and towards each end, and

- an inner hollow structure providing a grip for a penetrating object adapted to rotated said adjusting screwing member (define)

- adjusting screwing shaft (11), penetrating said adjusting screwing member (12) having a shape fitting the circumference of the inner hollow structure of the adjusting screwing member, wherein said second screwing member interact with said first screwing section of the support members upon rotation of said adjusting screwing shaft in a manner increasing or decreasing the distance between adjacent support members and thereby said guide rails and said rigid belts.

2. An apparatus according to claim 1, wherein the support member (10) further comprises:

- a guide section (14) securing the support member in an upright position, and - a receiving section (15) for receiving the guide rails (2).

3. An apparatus according to claims 1 or 2, wherein a pressure means on each end of the adjusting screwing shaft (11) adapted for applying pressure on the setting mechanism from both sides.

4. An apparatus according to any of the preceding claims, wherein the pressure means is coil spring or a spiral.

5. An apparatus according to any of the preceding claims, wherein the pressure means is an electrical jack or a hydraulic jack.

6. An apparatus according to any of the preceding claims, wherein the when a control device attached to the adjustment pin is adapted for turning the adjusting screwing shaft (11).

7. An apparatus according to any of the preceding claims, wherein the when the control device is a motor.

8. A method for adjusting the gap width between ridge-belts of a grading device, the grading device comprising:

- an in-feed device (4),

- grading unit (1) and - receiving unit,

said grading unit (1) comprising;

- plurality of endless ridge-belts (3) arranged side by side and moved continuously in a forward direction, forming a gap there in-between, the gap being increased in the direction of movement, two adjacent belts receiving, conveying and releasing the products as the gap there between becomes grater than the product thickness into said receiving units, the ridge-belts being longitudinally supported by plurality of guide rails (2), and - adjusting device (9) arranged underneath said ridge-belts and supporting guide rails, said adjusting device (9) arranged for adjusting the distance between said ridge-belts, said adjusting device comprising;

- first screwing section (13), the first screwing section being an double action inner elevated portion (4) of a cylinder forming a screw tread structure extending from the centre of the cylinder and towards each opening, and

- a second screwing section (18), the second screwing section being an double action outer elevated portion (4) of a cylinder forming a screw tread structure extending from the centre of the cylinder and towards each end, and

- an inner hollow structure providing a grip for a penetrating object adapted to rotated said adjusting screwing member

- adjusting screwing shaft (11), penetrating said adjusting screwing member (12) having a shape fitting the circumference of the inner hollow structure of the adjusting screwing member,

wherein the gap width between the ridge-belts (3) is determined by the adjusting device (9) in that first screwing section (13) of the support member is adapted to fit second screwing section (18) of the adjusting screwing member (12) on each side of the adjusting screwing member (12), and pressure means on each end of the adjusting screwing shaft (11) adapted for applying pressure on the adjusting device (9) from both sides when the adjusting screwing shaft (11) is rotated in a manner increasing or decreasing the distance between adjacent support members and thereby said guide rails and said rigid belts.

9. A method according to claim 8, wherein one or more adjusting devices can be implemented on the grading apparatus, such as at the intake end and the outlet end of the grading apparatus.

10. A method according to claims 8 or 9, wherein even adjustment if the gap is obtained by turning the adjusting screwing shaft (11).

11. A method according to claims 8-10, wherein a control mechanism is implemented, the control mechanism comprising:

- pressure means, such as an electrical jack or a hydraulic jack

- a motor, and

- control board, - wherein the gap with is controlled on the control board, which co-ordinates the turning of the adjusting screwing shaft (11) by the motor and the pressure applied by the electrical jack or the hydraulic jack.