| 1. | A juice press having a pair of continuous pressing belts driven in a spaced vertical array, the spacing of the belts defining a gap that decreases as both belts are driven towards the base of the press, the base of the gap defining a pressing zone into which matter to be pressed can be placed, each pressing belt including linkages that define an open latticework, whereby, in use, displacement of the belts in the pressing zone presses the matter to cause juice to flow through the latticework of the belts, each pressing belt being driven by a sprocket that has cogs that project into the latticework to remove debris that may be collected therein as a result of the pressing action. |
| 2. | The juice press according to claim 1 wherein each pressing belt comprises a plurality of spaced apart parallel links pivotally secured end to end. |
| 3. | The juice press according to either claim 1 or 2 wherein the belts travel over a perforated support collector. |
| 4. | The juice press according to claim 3 wherein the press includes in descending order a free juice zone, a first pressing zone and a second pressing zone, each zone having a separate collector. |
| 5. | The juice press according to any one of the preceding claims wherein each belt includes spaced outwardly projecting barrier members that meet towards the base of the press to close off the top and bottom of the pressing zone defined by the converging surfaces of the belts. |
| 6. | The juice press according to claim 5 wherein each barrier member is inherently deformable to allow the barrier members to come into abutting contact to close off the top of the pressing zone. |
| 7. | The juice press according to claim 6 wherein each barrier member inherently returns to a neutral position after leaving the pressing zone. |
| 8. | The juice press according to claim 7 wherein each barrier member comprises a plurality of metal plates encapsulated in polymeric material, the plates being biased to the neutral position. |
| 9. | The juice press according to claim 8 wherein the plates are biased by the polymeric material interconnecting two plates. |
| 10. | The juice press according to claim 2 wherein each drive sprocket has spaced elongate cogs that fit into the gap between the parallel links. |
The commercial production of wine requires highly efficient continuous presses that have the capacity to extract the maximum amount of juice from grapes without contaminating the juice with debris and particulate material. The presses need to be efficient in operation and hygienically clean to avoid the spread of bacteria.
It is generally considered that it is preferable to press the grapes to release the juice without shearing the grape causing its disintegration.
It is these considerations that have brought about the present invention.
In accordance with one aspect of the present invention there is provided a juice press that includes a pair of continuous pressing belts driven in a spaced vertical array, the belts defining a gap that decreases as both belts are driven towards the base of the press, the base of the gap defining a pressing zone into which matter is to be pressed can be placed, each pressing belt including linkages that define an open latticework, whereby, in use, displacement of the belts in the pressing zone presses the matter to cause juice to flow through the latticework of the belts, each pressing belt being driven by a sprocket that has cogs that project into the latticework to remove debris that may be collected therein as a result of the pressing action.
Each belt may include spaced outwardly projecting barrier members that meet towards the base of the press to close off the top and bottom of the pressing zone defined
by the converging surfaces of the belts.
Preferably each pressing belt comprises spaced apart links secured end to end on a pivot pin.
Preferably the linkages travel over a perforated support plate and a drain tube is positioned behind the support plate.
In a preferred embodiment the press includes two vertically spaced pressing zones, each pressing zone having a separate collector.
An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a front elevational view of a wine press, Figure 2 is a detailed view of a lower portion of the press, Figure 3 is a cross-sectional view taken along the lines 3-3 of Figure 2, Figure 4 is a cross-sectional view of the press taken along the lines 4-4 of Figure 1, Figure 5 is a cross-sectional view taken along the lines 5-5 of Figure 1 of a drain tube that forms part of the press, Figure 6 is a front view of part of the drain tube of Figure 5, Figure 7 is a cross-sectional view taken along the lines 7-7 of Figure 1 of part of a pressing belt, Figure 8 is a side elevational view of a barrier member that forms part of the press, Figure 9 is a side elevational view of the barrier member in a compressed configuration, Figure 10 is sectional view taken along the lines 10-10 of Figure 8,
Figure 11 is an enlarged view of the circle 11 of Figure 8, and Figure 12 is a plan view of part o a pressing belt.
As shown in Figures 1 to 4, a wine press 10 essentially comprises two pressing belts 11 and 12 supported by a frame 15 to extend in a vertical array closely spaced from one another. Each belt is driven at its base by a drive sprocket 55,56 and at the upper end via an idler sprocket 57,58. The belts are spaced to define a gap 16 at the upper end that converges as the belts move downwardly to terminate in a lower section 17 in which the surfaces 21,22 of the belts 11 and 12 are parallel yet closely spaced apart. The convergence of the surfaces 21,22 of the belts acts to compress grapes that are positioned within the gap 16 to carry out the pressing action. Each pressing belt 11,12 consists of stainless steel linkages 50 that define an open latticework and as the grapes are compressed the juice flows through the latticework to be collected behind the belts in elongate collectors 30, 31.
As shown in Figures 1 and 4 the pressing belts 11,12 are supported in a single vertical plane in a rectangular enclosure 15 which is comparatively narrow when viewed side on-see Figure 4. An inlet tube 24 extends into the center of the framework 15 to feed into the V-shaped gap 16 defined by the opposed surfaces of the belts 11,12. The tube 24 feeds into a tunnel 60 defined by the mouth of the V between the belts 11 and 12. The mouth is defined by arcuate plates 18 and 19 that cover the return of the belts on the idler sprockets 57,58.
The inlet tube 24 feeds the tunnel 60 defined by the belts 11, 12 and inclined side plates 61 and 62 that extend to the base of the press 10. The grapes flow down the tube 24 into the tunnel 60. At the base of the tunnel 60 the
gap 16 between the belts 11 and 12 is rapidly decreasing and this constitutes the first pressing zone 27. As the belt surfaces converge towards the narrowest point at the base of the V there is a parallel section at the base of the press which constitutes the second pressing zone 17.
The area 28 above the first pressing zone 27 facilitates collection of free running juice.
The collectors 30 and 31 are shown in Figures 1, 4,5 and 6 and each comprise a stainless steel fabricated section that extends substantially vertically to be parallel to the path of the pressing belt 11 or 12. Each collector has a perforated front face that is positioned directly behind the belt 11 and 12 and inclined rear walls with side panels defined by the plates 61 and 62. Three baffles 38, 39, & 41 extend across the collector as shown in Figure 1 to define three collection zones. Thus, the collector 31 comprises a first vertical section 32 that is positioned behind the lower section 17 and then an outwardly diverging section 33 that runs to the top of the press. This section 33 sits behind the outwardly inclined position of the pressing belt 12. Five spaced support brackets (not shown) extend perpendicularly to the collector to secure the collector 31 to the frame 15.
Three drain tubes 35,36, 37 are provided along the length of the collector 31. The first tube 35 is positioned about halfway up the collector above the baffle 38 and collect free running juice. The second tube 36 is at the base of the first pressing zone 27 and the third tube 37 is positioned at the base of the second pressing zone 17.
Baffles 38,39 are positioned between the top of the collector and under the first drain tube 35 to define a free running juice zone. A baffle 41 is positioned at the base of the second drain tube 36 to collect juice from the first pressing zone 27. Baffle 41 and the lower wall 42 of the collector facilitates collection of the juice from the second pressing zone 17. In this way, juice from the
free running section, first pressing and second pressing zones 27,17 can be collected independently.
The front surface of the collector 30 or 31 is perforated stainless steel as shown in Figure 6. The perforations 45 allow the juice that flows through the belt latticework to enter the collector 30 or 31 whilst at the same time reducing the likelihood of collection of debris. In a preferred embodiment the perforations 45 in the collectors 30,31 are of a 4mm diameter with a 6mm vertical pitch and a 5.5mm horizontal pitch. The collectors 30,31 are fabricated from square tube of stainless steel and are mounted behind each of the pressing belts 11,12 and welded or bolted to the frame 15.
Details of the pressing belts 11,12 are shown in Figures 2 and 12 from which is should be noted that each belt comprises a series of stainless steel links 50 that are mounted in parallel spaced arrays on linkage pins 51.
The links define an open latticework through which juice from the compressed grapes can flow. At every sixth link 50 the belt 11 supports an upwardly extending barrier member 52 that extends at 90° from the surface of the conveyor by about 50mm.
As shown in Figures 8 to 10 each barrier member 52 comprises an array of rectangular metal plates 71,72, 73,74 encapsulated in rubber to assume a free standing triangular configuration shown in Figure 8. The encapsulated plates are secured across an elongate hooked bracket 76 that clips across one chain link as shown in Figures 8 and 9. The plates 71 to 74 are constructed of steel embedded in the rubber in a slightly spaced manner and the two extreme plates 72,73 are interconnected by a longer rubber band 80. The narrow gaps between adjacent plates and the band 80 give the barrier a degree of
flexibility but also cause the barrier to assume the neutral position shown in Figure 8. This is the position in which the barrier means travels up the rear of the conveyor as shown in Figure 1 and initially descends down into the pressing zones. However, as shown in Figure 2, as the barrier means 52 descend opposite barriers they come into contact with each other and the flexibility allows them to collapse progressively until they assume the abutting contact that is shown in the lower regions of Figure 1 in which the panels 72,73 and the rubber band 80 assume one parallel line. In this configuration shown in Figure 9, the two adjacent barrier means 52 are pressed firmly into engagement effectively closing off the pressing zone and preventing outward escape of the fruit.
It becomes impossible for the fruit to escape either upwardly or downwardly and thus at least a 2: 1 compression ratio is exerted on the fruit. The barrier means 52 also have the role of urging the fruit into the pressing zones because they are designed in the manner that upward pressure against the horizontal or lower plates 74,73 is resisted by the geometry of the barrier members 52. Thus as they come together they force the fruit into the first pressing zone 27 and ensure at the second pressing zone 17 the compression is much higher.
It is understood that the barrier means as described herein are only one means of carrying out this function and it is understood that many other possibilities are envisages such as the use of rubber diaphragms that can compress into engagement to ensure that the top and bottom ends of the pressing zones are sealed off. The rubber diaphragms could then spring back into the neutral position as the conveyors complete the return leg. It is further understood that the encapsulated arrangement of the barrier means is designed in a manner to ensure against collection of unwanted debris or juice to maintain the high degree of cleanliness
of the components of the press.
The barrier members 52 operate as collectors of solid material in the tunnel 60 and then to act as boundaries of the pressuring zones 27,17 as the surfaces of the pressing belts 1,12 converge as shown in Figure 1.
The pressing belts 11,12 are driven in synchronization by a pair of spaced drive sprockets 55,56 mounted at the lower end of the press. The return of the belts 11,12 is effected through idler sprockets 57,58 mounted at the top of the press 10. As shown in Figures 1 and 7, each drive sprocket 55,56 has a tooth formation that comprises speed elongate cogs 59 that fits closely between the parallel links 50 that define the latticework of the conveyor belts 11,12. In this way the cogs 59 perform two functions, namely they drive the pressing belt 11 as the sprocket 55 rotates but also by filling the space between parallel linkages 50 effectively pushes out any debris or compressed matter that may have collected in the belt, thus causing the debris of the collected matter to fall into a collection zone at the base of press, thus cleaning each belt 11, 12 as it is driven around the drive sprocket 55,56. The compressed matter known as marc is collected at the base of the press in a collector (not shown).
The press described above is thus a continuous self cleaning press that whilst it is specifically designed to press grapes can be used in many other fields such as fruit juice extraction and the pressing of cheese curds. The press is capable of processing about 40,000 litres of product per hour with produce based on a ratio of 60 to 70% free running fluid to 40 to 30% non compressed solids. The compression ratio on the solids is about 2: 1. The design of the linkage of the pressing belts is such that each belt presents gaps of about 1. 5mm
by 27mm every second link. The barrier members that are attached to the belts seal the top and bottom of the pressure zones and also assist in the pick up of solids on the way to the pressing zones. The solids stay in constant contact with the belts and there is no shearing or movement between the solids and the belt, thus assuring that the grapes are gently pressed as they travel down the tapered pressing zones. The position of the delivery tube ensures that solids are positioned in the throat of the compression area allowing the free draining fluid to rise in the section that separates the free running juice section from the first pressing zone. The angle of the tunnel 60 can be adjusted to determine the compression ratio and ensure smooth flow of the product.
It is envisaged that the speed of travel of the belts will be relatively slow such as a drive sprocket speed of between 30 to 50 revolutions per minute. In the preferred embodiment the position of the barrier members and arrangement of the conveyors produce pressing zones that are about 50mm by 32mm by 200mm.
The press can be run automatically by controlling the rate of product input and the actual travel speed of the pressing belts. A central control unit will control these variables and other variables that could be monitored would be pressure and volume sensors on the inlet pipe and fluid outlet pipes as well as means to monitor the volume of the compressed product.
In the preferred embodiment the wine press is designed to be used in an aerobic manner thus allowing air to contact the grapes as they are pressed. It is however understood that where an anaerobic pressing process is required the whole press could be located in a vacated enclosure ensuring pressing in anaerobic conditions.