CHEESE BLOCK FORMING TOWER OF VARIED TAPER

Abstract: A cheese block forming tower(4) has a column (5) with an upper, imperforate section (1) tapering outwardly from top to bottom by approximately 5 %, a middle perforate section (2) similarly tapered but by only approximately 2 %, and bottom section (3) which is imperforate and only nominally tapered. Suction, via port (12), can be applied to draw curd into the tower. Alternatively pressure can be applied, via port (12), to compress and push downwardly the pillar of curd in column (5).

Description: CHEESE BLOCK FORMING TOWER OF VARIED TAPER TECHNICAL FIELD OF THE INVENTION This invention relates to a cheese bloc!: forming tower and a multi-tower installation incorporating at least one such tower The invention also relates to methods of manufacturing blocks of cheese utilising various kinds of cheese towers in both cases particularly when a common supply is pro\ ided to the towers. BACKGROUND OF THE INVENTION Producing cheese blocks by utilising a pt rforated column contained in a tower is known. The method consists primarily of charging a column with curd whereby the lower curd particularly that at the bottom of the pillar of curd is compressed by the weight of the curd thereabove. In this processing the comp, ession causes whey to be expressed through the perforations. The pressure in the tower chamber about the column is reduced with typically a vacuum being created therein. This removes air from the curd and thereby assists in the uniform compression thereof and facilitate; extraction of the whey through the perforations. Individual blocks are severed from the bottom of the curd pillar by a cutting arrangement. Apparatus and methods of this type are de scribed in various patents from in or about 1966. UK Patent 1,187,964 describes an early design of a cheese tower of this nature. Since 1966 many developments have oeen proposed and described to increase the throughput while maintaining the desired consistency and uniformity of the cheese produced by these kinds of cheese towers. These developments include "multi-tower" installations, that is, providing a bank of such towers olten fed from a common supply rather than having independent supplies. UK patent 1542844 and USA patents 3,982,480 and 4, 539,902 and our NZ Patent Application 265118 describe some of these developments. In our NZ patent application 265118 we disclose a tower having a column height extended beyond that of the columns of previously known towers ard the throughput benefits that arise therefrom. However with these known towers there remain various limitations to throughput particularly with common fed "multi-towe " installations. While this is partly a limitation of the apparatus it is also partly the methods used in producing cheese utilising these. DISCLOSURE OF THE INVENTION An object of this invention is to provide a cheese block forming tower suitable for use in multi-tower installations that it is envisaged will provide an improved through-put over known towers while maintaining the appropriate integrity of cheese blocks produced. It is also envisaged that this invention will be suitable for use in combination with at least our other two inventions being concurrently filed. These claim priority from New Zealand patent application No 333113 and Australian patent application No. PP7443/98. A further object is to provide an improved method of manufacturing cheese blocks or at least provide a useful choice According to a first aspect of this inventicn there is provided a cheese block forming tower having a column thereof with a curd inlet port and an associated inlet pressure control port to draw curd through the inlet port into the column, characterised in that the column tapers outwardly to provide an increasing cros: sectional area from substantially an uppermost input section to a lower section with the extent of the tapering being greater in the upper section than in the lower section. According to a second aspect of this invention there is provided a cheese block forming column as described in the preceding paiagraph wherein at least an upper portion of the upper section is imperforate and the curd inlet port and the associated pressure reduction port are formed in that upper portion. According to a third aspect of this invention there is provided a cheese block forming tower as described in either of the two immediat ely preceding paragraphs wherein an imperforated section is provided in a lowermost portion of the lower section of the column. According to a fourth aspect of this invention there is provided a cheese block forming tower as described in any one of the three immediately preceding paragraphs wherein the curd inlet port is of less volumetric flow capacity than the associated inlet pressure control port. According to a further aspect of this invention there is provided a cheese block forming tower as described in any one of the four immediately preceding paragraphs including a block severing device coupled to a lower end thereof adapted to sever blocks of cheese from a parent pillar of curd formed within the tower column into a receiving chamber, characterised in that pressure reduction means are coupled to the receiving device to enable a vacuum to be created therein independently of any vacuum provided in the tower. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a partly schematic and partly fragmented longitudinal sectional drawing of a preferred embodiment. BEST MODE OF CARRYING OUT THE INVENTION A tower 4 is generally of known structure comprising a perforated column 5 with a severing device 6 and a receiving chamber 7 at a lower end thereof. A chamber 8 is provided about a perforated section of the column 5 to assist whey extraction from a pillar of curd in the column 5. Preferably the height of the tower is "extended" and the upper section thereof imperforate as characterised in our New Zealand patent application 265118. A pressure reduction or vacuum facility 10 is provided to chamber 8. Preferably a deep vacuum pump 10b is provided operable through control valve 10a to provide a required vacuum in chamber 8. By so enhancing th>3 extraction capability a desired level of vacuum in chamber 8 is achievable rapidly. This capability to rapidly change the vacuum enhances the operational method of the apparatus. Preferably a pressure reduction or vacuum facility 9, incorporating pump 9a and valve 9b, separated from vacuum facility 10, is provided to the receiving chamber 7. This enables independent vacuum control of chamber c and chamber 7 and thereby better control of the processing time of a tower 4. To ensure the separation between chambers 7 and 8 preferably a relative short lowermost section 3 of the column 5 bordering chamber 7 is imperforate. This will assist in maintaining sealing of the column 5 and more critically the associated plenum chamber 8 from the receiving chamber 7. This comes about as, in use, a plug of curd will be created in the imperforate section and effectively seal c hamber 8 from chamber 7. As is conventional severing device 6, such as a pneumatically operated guillotine blade 6a is provided at the junction between column 5 and chamber . Thus during severing of a block of cheese form the parent pillar of curd in column 5 the plug will sustain the required sealing. Preferably chamber 7 contains a ram operated load platform 17, a discharge ram 18 and a discharge gate 19 which operate in conjunction with guillotine 6a to remove severed cheese blocks while maintaining sealing of the column 5 from atmosphere. A curd inlet port 11 is provided in an upper portion of an uppermost section 1 of the tower 4. Inlet port 11 receives curd from associated feed line 1 la. Preferably control means, such as a valve is provided in line 1 la to control the supply of curd to port 11. Feed line 11a may connect to a curd supply common to other towers such as typical with a "multi-tower" installation. A pressure control facility, being port 12 and pump 12a, is associated with port 11. By pressure control facility 12 providing a reduced pressure (relative to that upstream of the curd supply in line 11a) in the uppermost section 1, curd will drawn into column 5. Preferably the volumetric flow capacity of port 11 is less than that of port 12. Preferably at least the upper portion of section 1 being the portion thereof associated with port 11 and pressure control facility 12 is imperforate. By operation of pressure control 12 cuid is intermittently charged via port 11 into the column 5. Controls including sensors 13, 14 are preferably provided to monitor the curd processing time in column 5 and related functions in particular the output rate of cheese blocks from severing chamber 7. The controls maintain the upper level of a pillar of curd in column 5 between upper datum level sensor 13 and lower datum level sensor 14 which are disposed within the imperforated upper section 1. Upon the upper level of a curd pillar lowering to lower datum 14 pressure ccntrol 12 is activated to draw in more curd and charge column 5 until upper level datum 13 is reached. Pressure control facility 12 can also be operated to increase the pressure in the interior of section 1 in particular the void above upper datum 13. This can be operated to assist compaction and downward displacement of curd in the column 5 and thereby to decree se the curd pillar processing time. Preferably the upper section 1 tapers outwardly from top to bottom to provide an increasing cross-sectional area therein. The taper cf section 1 is not substantial, the cross-sectional area at the lower end thereof being in the region of 105% that of the cross-sectional area at the upper end of section 1. At least the next lower section, in the preferred form being section 2 is similarly configured with the e.ctent of the tapering thereof being less than for the upper section 1. The taper of section 2 provides a cross-sectional increase over its length in the region of 2%. Preferably section 1 is about V 3 the length of section 2. This tapering may continue through into section 3 howevei in the preferred form section 3 is substantially parallel sided, a nominal outward taper only being provided to lessen resistant to curd passing therethrough. The perforated section of the column 5 surrounded by the traditional chamber 8 is represented by numeral 2 Sections 1, 2, and 3 may vary in length, in the preferred form section 1 being in the region of 2.4 metre ; and section 2 being in the region of 6.6 metres. The length of section 3 is preferably less -han the height of a block to be severed from the curd pillar. Further, the tapering of the upper section 1 may extend into the section surrounded by the chamber 8 and may be perforated in this lower portion. In known manner, whey drainage facilities 15 and "clean in place" facilities 16 are preferably provided from one or more of the sections 1, 2 or 3 of the column and the severing chamber 7.

Claims: THE CLAIMS 1. A cheese block forming tower having a column thereof with a curd inlet port and an associated inlet pressure control port to draw curd through the inlet port into the column, characterised in that the column tapers outwardly to provide an increasing cross-sectional area from substantially an uppermost input section to a lower section with the extent of the tapering being greater in the upper section than in the lower section. 2. A cheese block forming column as claimed in claim 1 wherein at least an upper portion of the upper section is imperforate and the curd inlet port and the associated pressure reduction port are formed ii that upper portion. 3. A cheese block forming tower εs claimed in claim 1 or claim 2 wherein an imperforated section is provided in a lowermost portion of the lower section of the column. 4. A cheese block forming tower as chimed in any one of the preceding claims wherein the curd inlet port is of less volumetric flow capacity than the associated inlet pressure control port. 5. A cheese block forming tower as ckάmed in any one of the preceding claims including a block severing device coupled to a lower end thereof adapted to sever blocks of cheese from a parent pillar of curd formed within the tower column into a receiving chamber, characterised in that pressure reduction means are coupled to the receiving device to enable a vacuum to be created therein independently of any vacuum provided in the tower. 6. A cheese block forming tower as claimed in any one of the preceding claims wherein an upper datum sensor and a lower datum sensor are provided in the imperforate upper section of the column, and associated control means operate to maintain the upper level of a pillar of curd in the eolumn between those datums. 7. A cheese block forming tower as claimed in claim 6 wherein the control means monitor the curd pillar processing ti e and the output rate of cheese blocks from the severing chamber. 8. A cheese block forming tower as claimed in any one of the preceding claims wherein the pressure control means associated with the inlet port can be operated to increase the pressure in the column above a pillar of curd therein to compact and downwardly displace the curd pillar to decrease the curd pillar processing time. 9. A cheese block forming tower as claimed in any one of the preceding claims of an overall height of substantially 9 meters with the upper most section being about V 3 the length of the next lower section and the cross-sectional area thereof increasing by some 5% and the cross-sectional a ea of the next lower section increasing by some 2%. 10. A cheese block forming tower substantially as herein described with reference to the accompanying drawing.

Inventors: MISSON GREGORY CHARLES, MISSON, GREGORY, CHARLES
Applicants: MISSON GREGORY CHARLES, SCHERPING SYSTEMS LIMITED, MISSON, GREGORY, CHARLES
Application year: 1999
Main classification: A01J25
IPC codes: A01J25