IES86085Y1 - A centrifugal product peel separation and removal apparatus - Google Patents

Abstract

ABSTRACT An agitator for a product peel removal system, the agitator comprising: a central axle having a plurality of outwardly projecting arms; and a product lifter at the distal end of at least one of said outwardly projecting arms; and an apparatus for product peel removal comprising a drum having an inlet for receiving product, an outlet for dispensing of product; and a plurality of perforations through which removed peel may pass; at least one agitator arranged within said drum and rotatable relative to said drum for agitating the product passing between said inlet and outlet; and means for controlling the retention time of product within the rotatable drum independently from the rotation speed of the agitator.

Description

Title A centrifugal product peel separation and removal apparatus.

Field of the Invention The invention relates to product processing, in particular the processing of fruit and vegetable products. In particular, the invention relates to an improvement in dry peel removal.

Background to the Invention The centrifugal effect gained by rotating articles within a container has been found to be useful in dry removal (i .e. no water used) of skin from skinned produce. Centrifugal separators comprising a rotating perforated drum have been utilised within produce processing systems to remove starch and loosened peel after steam peeling from produce fed through the drum. The centrifugal action of the rotating drum separates loosened peel from the product and carries or forces it through the perforations in the drum wall. An internal auger may be mounted within the drum to control the retention time of the product within the drum. An auger may also induce extra product mobility into the drum. The rolling and rubbing of product against the drum wall while passing through the drum loosens peel prior to removal through the perforations.

During the process of peel separation, considerable amounts of starch or other product residue can attach to and build up upon the inside of a drum. This residual material can subsequently be transferred back to the product which can considerably reduce the efficiency of the unit. The build-up may also partially block the perforations in the drum and thus prevent passing of peel out through the perforations.

One such prior art centrifugal separator comprises a central auger on which are provided lifters. The lifters agitate the product as the auger controls the residence time of the product in the drum. A result of the lifter being attached to the auger is that the amount of agitation ‘is limited to the speed of the auger. For example, an auger speed of 20 R.P.M. will give a maximum of 20 lifts/tumblings of the product per minute, where one lifter is provided per flight of the auger.

The speed of the auger in such a prior art system is limited by the minimum required retention time of product to achieve the required peel/ starch removal.

Existing equipment typically achieves only 80-85% removal of peel and starch.

Thus what is required is a centrifugal separator with improved effieiency of starch and peel separation. It is desired to remove 90-95% of peel and starch from product.

Summary of the Invention According to the present invention there is provided an apparatus for product peel removal/separation comprising a drum having an inlet for receiving product, an outlet for dispensing of product; and a plurality of perforations through which removed peel may pass, at least one agitator arranged within said drum and rotatable relative to said drum for agitating the product passing between said inlet and outlet to encourage pr0duct—to-drum rubbing primarily but also product-to-product rubbing, and means for controlling the retention time of product within the rotatable drum independently from the rotation speed of the agitator.

The apparatus acts as centrifiigal deskinner/separator/scrubber. The agitator is formed and arranged so as not to impart substantial movement of product in the axial direction of the drum, unlike prior art agitators in centrifugal deskinners wherein the agitator is integrated with an auger arranged to move product through the drum.

The centrifiigal deskinner of the present invention does not require an internal auger.

Residence time of product within the drum is controlled by other means. The drum is provided with a stand-alone dedicated agitator/lifter which can be run at any speed. As the residence time is independent from the speed of rotation of the agitator, the agitator may be run at far higher speeds than the prior art systems were able to achieve.

According to one embodiment, the agitator may be rotated at a speed of up to approximately 40 R.P.M., whereas prior art speeds are typically in the range of 20-25 R.P.M.. The speed may be variable.

The drum is preferably rotatable. The at least one agitator may be rotatable independently from said drum. Preferably the drum and agitator rotate in the same direction, however counter-rotation is also possible. In accordance with the present invention, an increase in rotation speed of the agitator may not result in a decrease in the retention time of the product with the drum.

The apparatus of any preceding claim wherein said at least one agitator comprises a central axle having at least one outwardly projecting arm. The agitator may comprise a plurality of outwardly projecting arms. At least two of said arms may be linked by a bridging member. The bridging member and arms may form a hollow frame about said central axle. Means may be provided for rotating said at least one agitator. Preferably said means for rotating said at least one agitator is controllable independently from any means for rotating said drum. It is advantageous for the drum to rotate faster than the actuator. Control means to control the speed of rotation of at least the drum and or control means to control the speed of the agitator may be provided.

Preferably at least one litter is provided at the distal end of each outwardly projecting arm. At least one lifter may be pivotally mounted on its outwardly projecting arm. The or each pivotally mounted lifter may comprises a scraper adapted to contact an internal wall of the drum. The scraper is preferably located on a leading edge of the lifter. The scraper may be integral to the lifter or attached thereto or mounted thereon. A clamping plate may be used to mount the scraper to the lifter. The scraper may extend the whole or part of the length of the lifter. The scraper is preferable of a length so that it projects beyond the lifter to contact the internal surface of the drum. It may be replaceable.

The pivotally mounted lifter may be arranged so that, in use, the scraper is biased against the internal wall of the lifter under the weight of product being lified. As the lifter and scraper rotate relative to the drum, the produce hold the scraper in close contact with the drum to urge any removed peel or starch stuck to the drum wall out through the perforations.

The claimed invention achieves an increase in performance by improving the efficiency of agitation of the product inside the drum. The present invention should achieve removal of 90-95% of peel and starch in use. The higher efficiency results from higher rotation speeds and increased agitation of the produce by the agitators. The efficiency may be improved further by increasing the number of agitators within the drum. For example, three agitators or lifters would result in a three—fo1d increase in the separation effect.

Preferably there is also provided means for removing/detaching starch or peel that becomes attached to the internal wall of the drum. This feature reduces the likelihood of removed peel/skin becoming re-attached to the product. Starch can act like a glue to bond removed peel or skin to a previously peeled product.

In one embodiment, a scraper or brush may be provided and arranged to make contact with the interior wall of the drum and scrape or brush starch or other residue therefrom.

The scraper may be static or moveable longitudinally to scrape the drum section by section. Means may be provided to transport removed peel/starch from the drum. A debris removal conduit having an outlet external to said drum for removal of debris separated from the interior wall of said drum by said brush may be provided. A auger may be provided within the conduit to assist removal. A spray may also be provided within the drum to spray liquid onto the interior wall of the drum to facilitate removal of build-up on the drum, In a preferred embodiment the perforations themselves are utilised to dispose of removed peel that builds up on the internal wall of the drum. To assist with the passage/propulsion of the build up from the internal wall of the drum to the outside, additional propulsion means may be provided. These means may take the form of a scraper or similar which is arranged to bear against the perforated wall of the drum. The rotation of the drum itself may be used to drive the propulsion means, alone or in combination with the counter-rotation of the actuator(s). The means for pushing are preferably located at the end of at least one outwardly projecting arm of the agitator.

The propulsion means will act to push/force/urge any starch or residual product that is attached to the drum out through the drum’s perforations, thereby increasing the effect of the centrifugal force.

The drum is intended for use with root vegetables, but could be used with any product.

The suitability of the drum would only be limited by the size of the slots in the wall of the drum that could not be larger in size than the product to be processed. The size of the slots may be dictated by the size of the product — for example baby carrots would require smaller slots/perforations than potatoes.

The drum may be tilted to encourage travel of product through the drum. A gate may be provided at the exit point of the drum, which may be used to control residence time. It may be possible to vary the position of the gate provided at the discharge of the drum to control the bed depth of product within the drum, together with the product retention time.

A partial ribbon auger may be provided to induce movement through the drum. The partial ribbon auger may have a small helix angle. Desirably the ribbon auger is located near the entry point of the drum and function to keep the inlet/in feed clear by encouraging movement away.

Alternate residence time control means may further be provided. Through use of independent agitation means and independent residence time control means, increased agitation is possible without effecting residence time.

The present invention permits the control of speed of the agitator independently from the product retention time within the drum. Preferably the means for rotating the or each agitator is controllable independently from any means for rotating said drum.

One or more inspection door may be provided in the drum to facilitate I service/maintenance of the machine. Hinges may be provided to enable the door(s) pivot between an open and closed position. Locking means are suitably provided to maintain the door(s) in a closed position while the machine is in use. The door(s) are suitably provided with slots so as to form functioning parts of the wall of the drum when closed.

The invention further provides an agitator for a product peel removal system, the agitator comprising: a central axle having a plurality of outwardly projecting arms; and a product lifter at the distal end of at least one of said outwardly projecting arms.

The agitator may comprise at least one set of at least three outwardly projecting arms.

The agitator may comprise multiple sets of at least three outwardly projecting arms: and at least three lifters, each lifter linking an arm from each set.

Each product lifter may be positioned substantially parallel to the central axle.

Each arm may extend substantially perpendicularly from the central axle. Preferably at least one lifter is pivotally mounted on its outwardly projecting arms. At least one scraper may be mounted on at least one lifter. Preferably the scraper is located on a leading edge of the lifter.

The invention further provides a centrifugal separator comprising an agitator as descibed above, an apparatus substantially as described herein with reference to and as shown in any one or more of the accompanying drawings, a centrifugal separator substantially as described herein with reference to and as shown in any one or more of the accompanying drawings, and an agitator substantially as described herein with reference to and as shown in any one or more of the accompanying drawings.

Brief Description of the Drawiggg Embodiments of the invention will be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is an end-on cross section view of one embodiment of an apparatus according to the present invention.

Figure 2.is a cross section view of a further embodiment of an apparatus according to the present invention.

Figure 3 shows the embodiment of figure 2 in use with produce within the drum.

Figure 4 shows a perspective View of the agitator from the drum of figures 2 and 3.

Figure 2 is 5 side-on cross section view of one embodiment of an apparatus according to the present invention.

Figure 3 is a cross section View of a further embodiment of an apparatus according to the" present invention.

Figure 4 is a cross section View of a further embodiment of an apparatus according to the present invention.

Figure 5 is a cross section View of a further embodiment of an apparatus according to the present invention.

Figure 6 is a cross section view of a further embodiment of an apparatus according to the present invention.

Figure 7 is a cross section view of a further embodiment of an apparatus according to the present invention.

Figure 8 an end view of an embodiment of an apparatus according to the present invention.

Detailed Description of the Drawiggg Figure 1 shows one embodiment of the apparatus for product peel removal of the present invention. The perforated drum 2 is indicated by the broken line, the drum comprising a plurality of perforations 4 through which removed peel may pass. The drum‘ comprises one agitator 6 rotatable relative to the drum for agitating product 8 within the drum to encourage product-to-product rubbing and to ensure that all products make as much contact as possible with the drum surface. As shown by the arrow, the ' drum is also rotatable. Preferably speed of rotation of the drum is between around 40 to RPM. The agitator is rotatable independently from the drum.

As seen, the agitator in this embodiment of the invention comprises a central axle 10 with multiple outwardly projecting arms 12. The arms project from multiple locations along the length of the central axle. In this embodiment, four agitator arms project from the central axle at each projection point along its length. 90 degrees separate each arm’s angle of projection. Lifters 14 act as bridging members to link the arms along the length of the central axle. The lifters run parallel to the central axle and are located a short distance from the inner wall 16 of the drum. Four lifters are shown in this embodiment however more or less are possible in alternative embodiments. Any reasonable number of lifters may be provided, including just one. In the embodiment shown each lifter has a triangular cross section, with one edge 18 of the lifter positioned substantially parallel to the inner wall of the drum, however other shapes of lifter are envisaged. The lifters and arms form a hollow frame about said central axle through which product can tumble.

A scraper 20 is shown attached to one of the lifters to push peel and other residue through the perforations as the lifter is displaced relative to the drum wall. Alternative forms and locations of the scraper are envisaged in alternative embodiments as described below in greater detail.

Figure 2 is a cross section View of a further embodiment of an apparatus according to the present invention. Three lifiers 14 are provided in this embodiment. At least one 15 of the lifters is pivotally mounted on the end of its arm 13. The pivot 17 is loose so the lifter has freedom of movement. Attached to the leading edge 19 of the lifter 15 is a scraper 20, the end of which is in contact with the internal wall of the drum. In use, the scraper is urged into contact with the wall to push removed skin present on the internal surface of the drum through the perforations. As shown in figure 3, the produce 8 on the lifter applies a force to the scraper, the force having a component in the direction of the drum wall, to hold the scraper against the internal wall of the rotating drum. The scraper is preferably formed from a food-grade material and may have a resiliently flexible form.

Figure 4 shows a perspective view of the agitator from the drum of figures 2 and 3. Four sets of three arms 12 are provided although more or less sets may be used in alternative embodiments. The pivotally mounted lifter 15 is shown also. It is possible that one, some or all of the lifters are mounted in this manner, with our without a corresponding scraper 20.

A further optional feature shown in this drawing is a bend at the far end of the statically mounted lifters. This bent end portion 21 assists in pulling product in from the feeder end of the drum. One or more of the lifters may have this form.

Figure 5 shows a similar embodiment to that shown in figure 1. However in figure 5 at least one of the lifters 38 is provided with a spring mounted scraper. The scraper is spring-mounted and projects out from a cavity within the lifter 38. The spring biases the scraper against the wall of the drum to increase its scraping efficiency.

Figure 6 shows another similar embodiment to that shown in figure 1. However in figure 6 the central axle of the agitator is off centre relative to the central axis of the drum. The agitator is smaller in size to accommodate a separate drum cleaning device 42 within the drum. The cleaning device incorporates a brush 44 which extends the length of the drum to clean the inner wall of the drum. The lifters in this embodiment only near an arc of the circumference of the drum in the region where product collects.

Figure 7 shows a similar embodiment to that shown in figure 6. However in figure 7 a scraper 46 is provided in place of the drum cleaning device, shielded from the product and agitator by a housing 50.

Figure 8 shows another similar embodiment to that shown in figure 6. However in figure 8 a rotating brush 52 with circular cross section is provided extending the length of the drum. A housing 54 is provided, within which a waste/debris removal auger 56 is also found. The waste auger sits Within a debris removal conduit (not shown) having an outlet external to said drum and acts in conjunction with the brush to clear away discharge removed from the drum wall by the brush.

Figure 9 shows a similar embodiment to that shown in figure 6, however in figure 9 the scraper 58 does not extend the length of the drum, instead it is carried along the length of the drum by a trolley 60 arranged to transverse the length of the drum. The scraper scraps peel and starch etc 61 onto a collection tray 62.

Figure 10 shows an arrangement 64 suitable for controlling product retention time. A pivotable gate '72 is moveable between a fully open position wherein the outlet of the _ drum is fully-exposed and discharge of the product is not impeded and a fully closed position where the outlet is sealed. The extent of restriction of flow of product from the outlet 78 by the discharge gate can be varied, which in turn permits the depth of the product in the drum to be controlled and varied.

Figure 1 1 shows a cross section of a drum in accordance with a further embodiment of the invention. Between drum inlet 22 and an outlet 24, an augered agitator extends throughout the length of the drum comprising four lifters. The agitator arms 26 extend at an angle from the longitudinal axis of the central axle. The angle of extension of each arm of each set is skewed so the distal ends 28 of each arm of the set meet the lifter at different positions. There are sets of arms in this embodiment. The arms are flat like ribbons. Each of these two sets 30 form a segment of a ribbon auger to control the flow of product away from the inlet into the body of the drum. In the region of the outlet of the drum a further ribbon auger 36 is provided to control the rate of discharge.

In each embodiment the hollow frame form of the agitator means that an increase in rotation speed of the agitator does not result in a decrease in the retention time of the product with the drum. The produce is not driven substantially though the drum by the agitator. The main role of the agitator is to lifi and drop the product. Separate means are provided to control the movement of product through the drum.

The words “comprises/comprising” and the words “having/including” when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

Claims (1)

Claims

1.An apparatus for product peel removal comprising: a drum having an inlet for receiving product, an outlet for dispensing of product; and a plurality of perforations through which removed peel may pass; at least one agitator arranged within said drum and rotatable relative to said drum for agitating the product passing between said inlet and outlet; and means for controlling the retention time of product within the rotatable drum independently from the rotation speed of the agitator. The apparatus of claim 1, wherein said at least one agitator is rotatable independently from said drum. An agitator for a product peel removal system, the agitator comprising: a central axle having a plurality of outwardly projecting arms; and a product lifter at the distal end of at least one of said outwardly projecting arms. An apparatus substantially as described herein with reference to and as shown in any one or more of the accompanying drawings. An agitator substantially as described herein with reference to and as shown in any one or more of the accompanying drawings.