IE56739B1 - Improvements to deep freezing apparatus - Google Patents

Description

The present invention relates to deep freezing apparatus.

One example of a deep freezing apparatus for ώ freezing foodstuffs is described in British Patent Specification No. 1,338,013 (Frigoscandia Contracting AB).

The Frigoscandia apparatus is intended specifically for deep-freezing foodstuffs, such as chopped or stewed spinach, and comprises two co-operating endless tracks which are co-extensive over a length of their travel so as to form between them a fixed space for the foodstuff to be frozen, the endless tracks co-operating with a freezing device for deep-freezing the foodstuff in the space between the two tracks.

Figure 1 of the accompanying drawings is a perspective view of an apparatus of the known kind which consists of two endless tracks A which travel through a freezing device or chamber B. Foodstuff to be frozen is sprayed between the tracks by a transversely reciprocating nozzle C^at input end C and when frozen is removed from the apparatus at end D. One of the endless tracks A is provided with transversely extending ridges directed towards the other track. Over the length within which they are co-extensive, the tracks are spaced apart a distance greater than the height of the ridges so that foodstuff in the space between the two tracks is frozen to & u form a continuous cake of the product. At the output end 0 of the apparatus, the two tracks separate to detach the cake from the tracks and to break the cake. The product φ is then broken into smaller pieces by means of two rolls provided with projections. The projections are laterally J offset on the two rolls with one series of projections acting as supports for the cake and the other series of projections serving to break the cake.

Certain disadvantages are associated with 10 the prior art deep freezing apparatus.

Firstly# the means for breaking the product, whilst perfectly adequate for a fibrous foodstuff such as spinach# is not reliable or effective when dealing with a non-fibrous foodstuff such as cream. Sections of frozen cream which are not broken into sufficiently small pieces result in product wastage.

A second disadvantage associated with the prior art apparatus occurs when freezing cream. A very even spread of product is required across the apparatus when cream is being fed between the tracks. This even spread of product is difficult to achieve with prior art feeding means.

Thirdly# not all of the frozen product is detached from the track of the known apparatus. The product clings to the track and subsequently falls - 3 onto the floor of the machine and is lost during the return Journey of the track to the feeding means.

A further disadvantage v/ith the prior art apparatus is that it is prone to lose some of the freezing medium, normally propylene glucol, particularly at the ends of the apparatus. V The object of the invention is to provide an improved deep freezing apparatus .

According to the present invention there is 10 provided deep freezing apparatus for foodstuffs comprising two co-operating endless tracks which are co-extensive over a length of their travel from an input end to an output end cf the apparatus so as to form between the tracks a fixed space for the foodstuff to be frozen, feed means for feeding the fluid foodstuff to said input end, freezing means for freezing the foodstuff in the fixed space into a continuous cake, and a weir settable at a predetermined height at the input end of the apparatus for controlling the supply of foodstuff thereto.

Deep freezing apparatus embodying the present invention will now be described, by way of example, with reference to the accompanying diagrammatic drawings.

In the drawings: Figure 1, as already mentioned above, is a perspective view of apparatus of the known kind; 6 Figure 2 is a perspective view of a cake breaking means; j Figure 3 is a cross-sectional view of the shaft of the product breaking means along 3-3' of Figure 2; Figure 4 is a perspective view of a foodstuff feeding means; Figure 5 is a cross-sectional view of the foodstuff feeding means along 5-5* of Figure 4; and Figure 6 is a cross sectional view, on a reduced scale, of a collecting tray forming part of a deep freezing apparatus according to the invention.

Referring to Figures 1, 2 and 3, of the drawings, the cake breaking means 20 which is provided at the output end D of the apparatus comprises a rotatable shaft 21 mounted in journals 22. The end 23 of the shaft 21 is provided with a cog wheel 24 to enable the shaft to be rotated by a chain drive (not shown). For breaking the frozen cake into smaller pieces, the shaft 21 is provided with a plurality of spurs 25 which engage the cake as it comes out of the apparatus.

Referring to Figures 1, 4 and 5 of the drawings, the foodstuff feeding means 30 which is provided at the £ i input end C of the apparatus comprises a weir 31 and a pair of adjusters 32 which are used to adjust the orientation of the weir. The weir 31 is provided with a well 33 into which foodstuff such as cream is fed via pipe a 34. When the well 33 is full, the cream flows over lip 35 into the apparatus. The angle and orientation of the weir I are altered so as to regulate the flow of cream into the apparatus.

Referring to Figures 1 and 6, collecting tray 40 is located underneath the apparatus so as to collect frozen foodstuff falling from the lower track.

The tray 40 is provided with sloping walls 41 and the tray is sloped towards one end of the apparatus so that the collected cream may be pumped back into the feeding system.

As is common practice in the food industry, all surfaces in contact with foodstuffs are of a high quality stainless steel.

Trays (not shown) are provided at ends C and D of the apparatus to collect any of the freezing medium, such as for example propylene glycol, which may drip from the apparatus. The freezing medium is collected in containers which are periodically emptied back into the apparatus.

The operating temperature ranges of the ( - 6 propylene glycol, for the freezing of cream, are between -18°C £nd™22oC. Before the cream is fed into the apparatus, the cream is taken through a pre-cooling means, p where the cream is cooled by a medium, such as water, to approximately -p10°C.

Claims (6)

1. Deep freezing apparatus for foodstuffs comprising two co-operating endless tracks which are co-extensive over a length of their travel from an input end to an output end of the apparatus so as to form between the tracks a fixed space for the foodstuff to be frozen, feed means for feeding fluid foodstuff to said input end, freezing means for freezing the foodstuff in the fixed space into a continuous cake, and a weir settable at a predetermined height at the input end of the apparatus for controlling the supply of foodstuff thereto.

2. Deep freezing apparatus according to Claim 1 including cake breaking means at the output end of the apparatus, wherein the cake breaking means comprises a rotatable shaft mounted parallel to the axis of rotation of the tracks, the shaft having a plurality of saw tooth like spurs extending therefrom whereby to effect a sawing action cn the cake when the shaft is rotated.

3. Deep freezing apparatus as claimed in Claim 2, including means for altering the position and orientation of the weir sc as to regulate the flow of foodstuff into the apparatus.

4. Deep freezing apparatus as claimed in any one of the preceding claims, including a collecting tray located beneath the lover track and pumping means to return to the input end of the apparatus foodstuff collected in the said collecting tray.

5. « Deep freezing apparatus as claimed in any one of the preceding claims, wherein the freezing means comprises means for directing a freezing medium onto said tracks, and means for recycling the freezing medium, the recyling means comprising trays disposed at the ends of the apparatus to collect any freezing medium carried by the tracks and means for returning the freezing medium tc the apparatus.

6. 8. Deep freezing apparatus substantially as herein described with reference to and as shown in any of Figures 2 to 6 of the accompanying drawings.