GB2173758A - Improvements relating to conveying systems - Google Patents

Abstract

A conveyor system for moving for example boxed cakes 28 from an upper level to a lower level, such as between floors in a building, comprises a pair of conveyors 10, 12 with a pair of faces lying opposite, the boxed cakes being transported by being engaged frictionally between the opposed reach faces. The opposed reach faces have surfaces of a resilient nature e.g. flexible foam material or bristles. <IMAGE>

Description

SPECIFICATION Improvements relating to conveying systems This invention relates to conveying systems, and in particular concerns a conveying system for the transportation of articles or objects between different heights, such as for example the transportation of objects between two different floors in a building.

There are of course many conveying systems for the transferrance of articles or objects between different heights, but different articles and objects require different conveying systems, and in for example a cake making and packaging factory there is frequently a need to transport cakes from say an upper manufacturing floor in the building to a lower packaging and despatch floor in the building. The cakes may comprise packages of several cakes where these are small, or single package cakes where the cakes are larger. The cakes may be in cardboard boxes, or in plastic trays or may be otherwise packaged. For example they may simply be wrapped in flexible transparent film material.In any event, in such an installation, there is a need for a conveying system which transfers the cake packages from an upper floor to a lower floor to handle and deliver these packages on the one hand in such a manner as not to damage the cakes contained in the packages, but on the other hand at the factory production speed, which can be quite high, in order not to cause blockages in the system.

In cake factories, these two objectives are met in fact by using a spiral slide construction in which a fabricated spiral chute extends from the upper floor to the lower floor. The cake packages are discharged into the chute and then slide down same to the lower level. The design of the chute is critical in that the helix angle of the chute must be selected in relation to the type of packages to slide thereon so that the packages neither slide too slowly nor too quickly on the chute and also in relation to this particular aspect, the chute base and an outer chute edge must be designed to ensure the correct degree of friction between the packages and the surfaces. Therefore the chute base is in the form of a plurality of spaced metal rods whose upper surfaces define the supporting surface of the tray, these rods being secured together at their undersides by radial bars welded thereto.

As can be appreciated, the conventional spiral chute arrangement on the one hand represents an expensive part of the system, and on the other hand it is in practice a source of trouble during running conditions, because frequently the packages stick in the chute, or slide down too fast, each of which events can cause blockages in the production and therefore downtime of the plant. It is to be noted furthermore that the atmospheric conditions can indeed change the friction characteristics between the packages and the chute surfaces, which can in turn lead to a variation in the efficiency of sliding of the packages in the chute.

The present invention was conceived in order to overcome the difficulties with these spiral chutes as experienced in cake factories, but it is to be appreciated that the invention can be applied in any instance requiring equivalent handling and conveying of articles or objects which in themselves are of a somewhat fragile nature such as are cakes, and although reference is made herein specifically to cake packages, it is intended that other articles should be covered where the context admits.

In accordance with the invention there is provided a conveying system for transporting articles or objects between different heights comprising means defining two conveyor reaches which lie face to face and which can be moved in the direction of their lengths, said conveyor reaches being adapted to extend between different heights and having article engaging surfaces which are of a resilient nature, so that articles can be engaged between the opposing faces of the conveyor reaches firmly but lightly, enabling the transport of the packages by the conveyor reaches between the different heights in a positive and held fashion.

Preferably, the said reaches will be defined by two endless conveyors arranged face to face to provide a holding gap between the said reaches, the conveyors being of approximately the same length so that at one end of the reaches is defined a mouth into which the articles or objects can pass so as to be gripped by respective conveyor surfaces and transported by the conveyors to the other end defining an outlet from which the articles or objects are ejected.

In a particular installation, the conveyors may be arranged to extend vertically, and at the top end they define the said mouth. One of the conveyors may be higher at the top end than the other and the articles or objects pass towards the higher end but are delivered to the mouth at a position immediately above the lower end, an appropriate guide plate and side guide being provided for this purpose so that the articles or objects will be presented in the best attitude for being engaged by the moving conveyor surfaces and for being drawn into the mouth and for being transported by the said reaches. The conveyors preferably are driven at a speed greater than the delivery speed of the articles or objects, so that they are drawn quickly into the mouth, and are spaced apart by a sufficient amount whilst they are being transported by the conveyor reaches.

At the lower end, one of the conveyors has its end lower than the other conveyor to facilitate discharge of the packages along a curved guide leading from the lowermost end and curving smoothly into a horizontal conveyor which takes the articles or objects to another location for further process.

There may be an idler roller located at the outlet end of the conveyors, said outlet roller being located under the higher of the two conveyor ends at said outlet, but spaced above said curve guide, to assist the smooth deposit of the articles or objects on the guide and the discharge of same therefrom at the correct attitude.

The surfaces of the conveyors may be defined by a soft flexible material such as flexible polyure thane foam and the foam may be provided with transverse slits in order to prevent stretch of the foam as a result of use. The foam may be packed with a cotton webbing type material.

The conveyor may be of any suitable width able to handle packages or objects side by side.

It is also to be mentioned that the conveyors preferably are driven in synchronism, although it may be possible to drive only one conveyor whilst the other is left to idle.

The conveyors may be driven in reverse direction so as to be capable of moving articles or objects upwardly as well as controlling their movement downwardly.

It will be appreciated that the invention provides a system which, compared to the known spiral chute system, has a number of advantages, namely that the articles or objects are held by the conveyor surfaces during their movement from the high level to the low level, and therefore they are under positive control during this movement.

There is therefore no danger that the packages will travel faster or slower depending upon friction characteristics as happens with the spiral chute system. Because the movement of the packages will be more predictably controlled, there will be less blockage and breakdown time.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, wherein: Figure 1 is a diagrammatic side view of the conveyor system envisaged in the embodiment; and Figure 2 is a sectional elevation taken in a line II - il in Figure 1.

Referring to the drawings, Figure 1 shows the embodiment of the invention clearly, and it will be seen to comprise two conveyors 10, 12 which are driven continuously as indicated by the arrows 14 by means of a power unit 16, which may comprise an electric motor and gear box. The power unit 16 will be appropriately positioned, and its location in Figure 1 is only diagrammatic. From the power unit 16 a chain or belt drive 18 rotates a lower pulley 20 of the conveyor 12, and a transmission shown as a crossed chain 14 drives the lower roller 22 of the conveyor 10 to drive the conveyors in opposite directions so that the reaches 24 and 26 lie face to face and travel downwards in the same direction so as to hold packages 28 therebetween.

The packages 28 are delivered to the top end of the two conveyors by means of a feed conveyor 30 and they are held in suitable location by guide rails 32. The mouth 34 of the two conveyors 10 and 12 is defined by arranging for the upper roller 36 of conveyor 10 to be higher than the upper roller 34 of conveyor 12. As each package 28 enters the mouth 34, it is gripped first by the conveyor belt of conveyor 12 and is pushed horizontaily until it meets the downwardly travelling reach 24 of the belt of conveyor 10. The belt surfaces grip the package 28 and accelerate same into the space between the reaches so that the packages 28 as they travel between the belts are held evenly but spaced.The surface of each belt as shown in Figure 2 is defined by a layer of cellular foam 40 and 42, which may be a polyurethane flexible foam so that as the package 28 is gripped thereby, the foam surface yielding slightly to provide a firm but light grip on the package thereby to avoid damage to the product contained therein. The foam is adhered to a webbing belt 44 and 46 which is of sufficient strength to accommodate the tension which will exist as a result of the driving of the belts. The foam layers 40 and 42 may be provided with spaced transverse slits in order to avoid the stretching of the foam in use.The conveyors are preferably mounted so that they can be adjusted towards and away from each other in order to accommodate packages or articles of objects of different sizes, to ensure that the correct and light but firm grip will be applied to each package so that movement between the upper end of the conveyors and the lower end is controlled.

Reference numerals 48 and 50 for example illustrate different floor levels in a building, whilst numeral 52 indicates that at the upper level, the conveyor ends may be guarded by a guard.

At the lower end, the conveyors are again staggered in that roller 20 of conveyor 12 is lower than roller 22 of conveyor 10, and an idler roller 54 also of flexible foam material is positioned as shown in order to guide the packages downwards out of the outlet end of the conveyors onto a curved guide 56 so that the packages can change direction smoothly and become horizontal and be smoothly placed on a discharge conveyor 58 for transportation away from the lower ends of the conveyors 10 and 12 as indicated by arrow 60, to another location for further processing.

The conveyors can be driven in reverse if it is desired to use the system for elevating articles or objects.

Other materials than foam can be used for defining the conveyor surfaces. For example they could be of soft bristles.

The drive 16 will of course be adjusted in speed to enable faster or slower feeding of the articles or objects, as related to the speed of supply of same from the conveyor 30.

Claims (10)

1. A conveying system for transporting articles or objects between different heights comprising means defining two conveyor reaches which lie face to face and which can be moved in the direction of their lengths, said conveyor reaches being adapted to extend between different heights and having article engaging surfaces which are of a resilient nature, so that articles can be engaged between the opposing faces of the conveyor reaches firmly but lightly, enabling the transport of the packages by the conveyor reaches between the different heights in a positive and held fashion.

2. A conveying system according to Claim 1, wherein the said reaches are defined by two endless conveyors arranged face to face to provide a holding gap between the said reaches, the conveyors being of approximately the same length so that at one end of the reaches is defined a mouth into which the articles or objects can pass so as to be gripped by respective conveyor surfaces and transported by the conveyors to the other end defining an outlet from which the articles or objects are ejected.

3. A conveying system according to Claim 2, wherein the conveyors extend vertically, and at the top end they define the said mouth.

4. A conveyor system according to Claim 2 or 3, wherein one of the conveyors is higher at the top end than the other and the articles or objects pass towards the higher end but are delivered to the mouth at a position immediately above the lower end, an appropriate guide plate and side guide being provided for this purpose so that the articles or objects will be presented in the best attitude for being engaged by the moving conveyor surfaces and for being drawn into the mouth and for being transported by the said reaches.

5. A conveyor system according to any one of Claims 2 to 4, wherein the conveyors are adapted to be driven at a speed greater than the delivery speed of the articles or objects, so that they are drawn quickly into the mouth, and are spaced apart by a sufficient amount whilst they are being transported by the conveyor reaches.

6. A conveyor system according to any of Claims 2 to 5, wherein at the lower end, one of the conveyors has its end lower than the other conveyor to facilitate discharge of the packages along a curved guide leading from the lowermost end and curving smoothly into a horizontal conveyor which takes the articles or objects to another location for further process.

7. A conveyor system according to Claim 6, wherein there is an idler roller located at the outlet end of the conveyors, said outlet roller being located under the higher of the two conveyor ends at said outlet, but spaced above said curve guide, to assist the smooth deposit of the articles or objects on the guide and the discharge of same therefrom at the correct attitude.

8. A conveyor system according to any preceding Claim, wherein the surfaces of the conveyor reaches are defined by a soft flexible material such as flexible polyurethane foam.

9. A conveyor system according to Claim 8, wherein the foam material is provided with slits lying transverse to the reaches.

10. A conveyor system substantially as hereinbefore described with reference to the accompanying drawings.