DK172831B1 - Ice making apparatus and refrigerator for such an apparatus - Google Patents

Abstract

Apparatus for continuous production of flake ice comprises one or more refrigerated discs (20) mounted on a hollow shaft (18, 21, 71). Each disc (20) rotates in the vertical plane and includes a plurality of narrow internal channels (30) which extend substantially over all of the operative portion of the disc (20) and are of substantially equal length. The disc(s) (20) forms(s) the evaporator of a refrigeration circuit, and an evaporative refrigerant is circulated to the channels (30) in each disc (20) via the hollow shaft (18, 21, 71). During each cycle, water is applied to both external flat surfaces of each disc (20) at a first angular location and the film of water which adheres thereto freezes as the disc (20) rotates. The ice sheet so formed is removed from both sides of the disc (20) at a second angular location by scraper blades (40, 75).

Description

ψ in DK 172831 B1

The present invention relates to an ice-making apparatus of the kind set forth in the preamble of claim 1. The invention is particularly directed to a machine for making ice cream in flakes.

Ice cream in flakes is made as thin layers preferably 1.5 to 6.0 mm thick. The layers can be curved or flat, and the thin ice is usually broken into uneven 5-size surfaces and scraped off.

Ice cream in flakes is particularly suitable for packaging products such as fish or frozen foods, and the ice flakes can be packed close to the products. In other applications, such as chemical processes and cooling of concrete, where rapid cooling is important, ice in flakes is ideal because the flakes have the maximum possible cooling surface for a given amount of ice.

Ice in flakes is usually produced by applying water to the inside or outside of a cooled cylindrical drum. The water is supplied to the first angular position of the drum and adheres thereto in a thin layer at surface tension. As the drum rotates, the water freezes to a thin layer of ice which is broken by an ice removal device at a second angular position 15 co-current in the direction of rotation relative to the first angular position.

The thickness of the ice flakes can be varied by changing the rotation speed of the drum, by changing the evaporation temperatures, and by regulating the flow of water on the freezing surface. Because ice in flakes can be prepared by continuous operation without interrupting for a scraping cycle, less cooling is required to produce 20 tonnes of ice than with any other type of ice cream when comparing similar water application and evaporation temperatures.

In known machines the water is applied only to one side of the drum, ie. either on the outside or on the inside, but not on both. As a result, the cooled surface on the other side of the drum is unused and the ice-making operation constitutes an inefficient use of the cooling capacity of the machine.

Furthermore, when the ice removal device is only located at one side of the drum on which the ice is formed, the continued unbalanced force applied to this side of the drum to break the ice from the freezing surface accelerates the wear of the drum bearings.

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A further disadvantage of the known drum-type ice-making machines is that their capacity cannot be increased in that way. If you want to increase capacity, it is usually necessary to install a brand new machine. In addition to installing an additional cooled drum, it is also necessary to install another cooling unit including the motor, compressor and condensing unit and a new drive unit. Any upgrading in capacity will therefore include significant expenses.

10 In order to overcome the problems described above and to increase the production capacity of ice-making machines, it has been proposed to use chilled slices.

U.S. Patent No. 3,863,462 discloses an ice-making machine to produce, to a larger extent, ice in flakes, comprising one or more upright chilled slices rotating on a horizontal axis. Water or other liquid that can be frozen can be applied to both surfaces of the disc and freeze to flakes of ice as the disc rotates.

Then the flakes are removed from the disc in the form of ice flakes. Each disc is approximately 1.8 m in diameter and comprises a pair of large round aluminum spacers spaced 20 mm apart and sealed at their periphery to form a closed compartment. Deflection plates are disposed within the interior of the enclosed space to form incomplete passages through which a refrigerant is pumped to cool the disc surfaces.

However, the machine for making ice cream in flakes described in U.S. Patent No. 3,863,462 nevertheless exhibits several disadvantages including the following:

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(a) Due to the large flow passages within the disc, it is necessary to use a non-evaporative refrigerant such as a brine or glycol. Ie

25, that a "boiling" or evaporative refrigerant cooling by direct expansion is not suitable for use in the disc of the above-mentioned patent. A saline solution ----- L ·

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E1 · · r Si * rw · 3 GB 172831 B1 and glycol have low cooling capacity and large quantities of such refrigerants must be pumped through the disk to obtain the required cooling.

(b) Because a refrigerant such as a brine or glycol may be used, a separate cooling system is required to cool the brine or glycol.

(C) The slices are difficult to manufacture with the required tolerances. The discs having a diameter of 1.8 mm must be cast or machined by cutting and welded at their periphery, but the flat outer surfaces of the discs must not vary from the plane in which they can rotate by more than 1/8 mm.

For the reasons mentioned above, the ice-making machine described in U.S. Patent No. 3,863,462 is not suitable for commercial use.

The object of the present invention is to overcome or eliminate at least some of the disadvantages described above of the novel ice-making machines.

It is further an object of the invention to provide an improved cooled disc for use in connection with the ice-making machine.

This object is achieved according to the invention in that the ice-making apparatus initially stated is designed as defined in the characterizing part of claim 1.

The liquid applied to the disc is typically water which is frozen to form ice. The ice is removed in the form of flakes, as described above.

The water can be applied to the surface of the disc by rotating the disc through a trough of water or the like. Alternatively, the water can be sprayed onto the disc.

4 DK 172831 B1

The ice removal means preferably comprise a pair of scraper blades disposed on each of its opposite sides of the disk and extending radially along it. Each scraper blade 1 does not touch the disc, but is spaced at a small distance therefrom typically 0.05 to 1.0 mm.

= The ice is removed without any heat being generated.

5 As the disc rotates, each point on the disc's surfaces will undergo the following steps in succession: (1) water will be applied to the disc surface, (2) water will freeze to ice as the disc rotates with time, (3) the ice will be removed by ice removal means and the above said course will be repeated with each turn of the disc in a continuous process.

It will be apparent to one skilled in the art that the ice-making apparatus of the present invention has few moving parts and is relatively economical to manufacture.

Furthermore, the ice making apparatus is able to make use of direct expanding refrigerant with a "boiling" or evaporative refrigerant, thereby enabling a higher efficiency and freezing capacity to be achieved. Only one cooling system is required, the disks comprising the evaporator unit of the cooling system.

Furthermore, according to the invention, a cooling disc can be provided suitable for use in an ice-making machine, which disc has a number of relatively narrow internal channels for passage of an evaporative refrigerant therethrough, which channels extend substantially over the entire portion of the disc.

The disc typically has a circular shape and is adapted for rotation about an axis passing through its geometric center.

The disc is preferably of a sandwich or a laminate structure comprising two halves in which open channels have been etched or machined spontaneously into patterns which are mirror images of each other. When the two halves are aligned with each other to form the composite disk, opposite closed channels form inner channels. The pattern of the channels is such that they extend to substantially the entire plane of the disc and are substantially the same length so that the disc is uniformly cooled.

In a single disc machine, this cooled disc has a central opening 5 with a collar disposed therein. On the one hand, the collar receives a hollow shaft which supplies the compressed refrigerant. The collar has a series of radial bores which at their inner ends are connected to the hollow shaft. At their outer ends, the radial bores are in communication with the respective inlets for the channels extending through the disc and the inlets of the channels are arranged on the cylindrical surface of the disc opening.

The liquid refrigerant passes through the hollow shaft and into the inner channels of the disc, thereby evaporating to cool the disc.

The channel outlets communicate with other hollow shafts on the opposite side of the collar via another set of radial bores in the collar. The evaporated refrigerant is extracted through it by the hollow shaft of the compressor. The washer, collar and shafts form a single assembly which is rotated by a motor using a belt or sprocket for a tow wheel or sprocket on one of the shafts.

However, the disc can be rotated in other suitable ways. Eg. For example, the disc may be provided with a toothed periphery so that the disc can be driven by a gear exchange, either directly or by means of a chain drive.

20 In multi-disc machines, a plurality of discs are mounted on a common shaft, and the refrigerant is fed to ducts in each disc via a distributor and pipeline system. The discs are fed in parallel, and the lengths of tubing are substantially the same to ensure the same pressure drop in the refrigerant fed to the discs. The evaporated refrigerant can be extracted via the common hollow shaft.

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According to the invention, the channels can be substantially the same length. The open channels can be formed in the disc portions by etching.

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The invention is explained below with reference to preferred embodiments and the drawings, in which FIG. Fig. 1 shows an enlarged scale side view of one embodiment of the ice-making apparatus according to the invention; 2 on an enlarged scale the same in section along the line F-F in FIG. 1, FIG. 3 is an enlarged sectional side elevation of the one shown in FIG. 1, FIG. 4 is a sectional view of a quarter of the device shown in FIG. 1 shows the disc of the ice making apparatus; FIG. 5 is a sectional view of a portion of FIG. 4; FIG. 6 is a sectional view of a portion of one half of the one shown in FIG. 4; FIG. 7 is an enlarged sectional view taken along line B-B of FIG. 3, r i! FIG. 8 is an enlarged sectional view taken along line C-C of FIG. 3, 15 FIG. 9 on an enlarged scale, those of FIG. 2, ice making means,. ... fig. 10 on an enlarged scale from the end shown in FIG. 9; 11 from above the figures of FIG. 9, ice making means.

i '' iwla i m I ill t aa I 11 7 DK 172831 B1 fig. Fig. 12 is a perspective view of another embodiment of the multi-disc ice-making apparatus; 13 is a sectional view of FIG. 12 with multiple discs, FIG. 14 from above the figures of FIG. 12, ice removal means, FIG. 15 from the side illustrated in FIG. 14, ice removal means, FIG. 16, on an enlarged scale, the one shown in FIG. 12, and FIG. 17 is a sectional view of the mounting of the disc on the one shown in FIG. 16.

The FIG. 1 and 2, the first embodiment of the ice-making machine 10 comprises a frame 12 on which is mounted a water reservoir 11 and a pump 13. Water from the reservoir 11 is pumped by means of the pump 13 through an upwardly extending pipe 14 to a pair of 10 water sprayers 15 arranged above on each side of a rotating cooled disc 20. The water sprayers are oriented to direct water to both surfaces of the disc, thereby leaving a film of water which adheres to both surfaces of the disc. The disc 20 rotates in the direction indicated by the arrow in FIG. 1 and driven by the motor 16 via a belt or chain 17 and a pulling wheel 18. However, the disc 20 can be rotated by any other suitable means. Eg. For example, the disc 20 may be provided with a toothed periphery and driven by a gear exchange either directly or by means of a chain.

The cooled disk 20 has a plurality of channels therein and comprises the cooling element of a cooling circuit. The mounting of the cooled disc 20 is shown in more detail in FIG. 3. As can be seen in this figure, the disc 20 has a central circular opening in which is inserted a 20 circular collar 22. On the one hand, the collar 22 receives a hollow shaft 18 which supplies a refrigerant, while the collar 22 on the other side receives another hollow shaft 21 to remove the evaporated refrigerant. The shafts 18,20, the collar 22 and the disc 20 are fixed to one another and rotate as a single unit. For rotation, the shaft 18 is mounted in bearings 8, while the shaft 21 is mounted in bearings 23. The bearings 23, 25 are arranged in the respective bearing blocks, which are preferably adjustable and detachably mounted in the ice making machine frame 12. shafts 18 and 20 stir in conjunction with a cooling circuit capacitor in compressor respectively (not shown). O-rings 26, 24 are provided to seal the connections with shaft 18 and 21, respectively.

Attached to the shaft 21 is a traction wheel, a sprocket or a sprocket 18 which is rotated by the motor 16 via a belt or chain 17. The rotation of the traction wheel 18 results in rotation of the disk / collar / pipe assembly.

The cooled disc 21 is shown in more detail in FIG. 4-6. The disc 20 is of a laminated construction and comprises two discs 20A and 20B which are laminated together. Each disc 20A and 20B has a pattern with open channels 30A formed in the surface, e.g. by etching or with machining. The channel patterns are mirror images of each other, so that when slices 20A, 20B are bonded to each other, closed channels 30 are formed.

The disc is typically 4-10 mm thick and the channels are typically 3.5 mm wide x 2.5 mm high.

15 The channel pattern for one quarter of the disc 20 is shown in FIG. 4. The pattern for the lower right quarter is the opposite of the pattern shown for the upper right quarter, and the patterns for the upper and lower left quarters are mirror images of the patterns for the right top and bottom quarters. The channel pattern is designed such that (a) the channels are spread over substantially the entire surface of the disk so that all points on the surface are close to the refrigerant and (b) the channels are of substantially the same length so that there is uniform pressure drop. in the refrigerant in all the channels.

These two features ensure that the disc is cooled as uniformly and evenly as possible. Further, the provision of a thin-channel pattern allows the disk to be cooled using a vaporizing or "boiling" refrigerant as opposed to a saline solution. This results in faster and more efficient cooling of the disc.

Although the disc shown is composed of two layers, more than two layers can be used to form the laminated disc, if preferred.

Each channel 30 has an inlet 31 which communicates with the central opening of the disk. The outlets of the channels 30 are also located on the inner cylindrical surface of the disc on the opposite side of the inlets.

As shown in FIG. 3, 7 and 8, the collar 22 has a plurality of radial bores 27 in one half, the inner ends of which 32 are in communication with the hollow shaft 18, and the outer ends of which are in communication with the inlet 31 of the channels 30 in the disc 20. On the opposite half, the collar is provided with a plurality of radial bores 29 with outer ends communicating with the outlet 33 of the ducts 30 and the inner ends communicating with axial bores 28 which in turn communicate with the hollow shaft 21.

Condensed liquid softener is fed through shaft 18 through radial bores 27 into 15 of collar 22 and into channels 30 of disc 20 where it evaporates and cools. The evaporated refrigerant is drawn from the channel outlets 33 through the bores 20 and 28 and out through the hollow shaft 21 to the compressor (not shown) in the cooling circuit. In this way, the disc acts as evaporator in the cooling circuit.

As shown in FIG. 2, ice removal means 40 are mounted on frame 12 to break the ice 20 formed on the disc from the cooled surfaces. After the ice is broken by the slice, it descends through channel 50 and is collected in buckets 51.

An embodiment of a scraper blade assembly is shown in FIG. 9-11.1 in this embodiment, the scraper blades 52 are attached to the bottom edge of one arm of a pair of radial frame members 53, which in turn are attached to the support plate 51 which is secured by the bolt 59 to the crossbeam 56 of the ice-making machine. frame 12. The changed ends of the arms 53 are supported by the pendulum arm 54 which is pivotally attached to the bracket 55 of the machine frame. Because this mounting arrangement is sub-! supported by the main frame to a greater extent than by the shafts 18, 21, pressure on the bearings in 5 23 and 25 is eliminated and the life of such bearings is thereby extended.

The scraper blade assembly shown in FIG. 9 and 11 also comprise a bearing block 58 which is held between a pair of brackets 57 to ensure that the washer 20 and the working edges of the scraper blades 52 are aligned properly with one another.

The scraper blade assembly is of simple economic design, yet is easy to adjust and maintain. Furthermore, the scraper blade assembly scrapes the ice on both sides of the disc 20 at the same angular position so that the forces on the disc are balanced Because the ice is formed on both sides of the disc 20, the ice making machine of the present invention can be made more compact than the known drum machines in which the ice formed only on one side of the drum. Furthermore, because the freezing surfaces of the disc are in the immediate vicinity of the fabric softener, greater efficiency is achieved. The ice making machine has few moving parts and thus requires less maintenance than the existing machines. In the event that maintenance is required, the washer / shaft / bearing assembly shown in FIG. 3 is easily removed from the bearing mountings in the machine.

The machine can be started and stopped at intervals and the speed of the disc can be varied to produce products of varying clarity and consistency. A single disc with a diameter of 500 mm can produce more than half a ton of ice in a 24 hour period.

Another embodiment of the invention is shown in FIG. 12-17, which comprises a plurality of 25 chilled slices. As shown in FIG. 12 and 13, the multi-disc ice making machine comprises: a number of cooled discs 70 mounted on a common hollow shaft 71. The shaft 71 is mounted at its ends in combined bearing and sealing joints 65. An inlet port 68 is arranged at one end of the hollow shaft 7 in connection with a source of condensed liquid refrigerant, while the opposite end of the shaft 71 has an outlet port 67 for an inlet connection for the evaporated refrigerant. The disc 70 comprises a cooling circuit cooling unit in the same manner as that of FIG. 1-11.

The disc 70 is mounted in a water tank 59 which is typically made of stainless steel or fiberglass reinforced plastic. The tank 69 is mounted on a foot 61 which is preferably made of cast aluminum alloy. Spaced apart by a pair of flanges 72 is formed on the tank 69 and each disc 70 passes between a pair of flanges 72. Scraper blades 75 are arranged on top of the subsequent flanges 72 to break the ice layer formed on the discs 70 when the slices rotate past the leaves.

The washers 70 and shaft 71 are rotated by a pull wheel or sprocket 64 coaxially mounted 15 on shaft 71 and driven a chain or belt by a drive motor 63 via a gearbox 62. However, it will be apparent to one skilled in the art that other means can be used to rotate the discs 70. For example. For example, the tow wheel or sprocket 64 or one or more of the discs 70 may be provided with a toothed periphery and driven directly by a gear exchange.

The tank 69 is filled with water to the level 80, as shown in FIG. 13. As the disc 70 moves through the water in the tank 69, a water film will adhere to both surfaces of the disc due to surface tension. As the cooled disc 70 rotates in a clockwise direction as shown, the water which adheres to the cooled surfaces of the disc will freeze and form a thin layer of ice which is then broken from the disc surface of the scraper blade 75 positioned as shown. Any amount of water that does not stick to the surface of the disc 70 or which does not freeze will simply return to the tank 69. As a result, there is only a small waste of the liquid to be frozen.

The production of ice can be increased by reducing the temperature of the water in the tank 69 close to the freezing point and by increasing the rotational speed of the disc 70 and increasing the flow of refrigerant through the disc 70.

The design and construction of each cooled disc is substantially as described above with respect to FIG. 4-6.

A preferred design of the scraper blades is shown in FIG. 14 and 15. Each scraper blade 75 is releasably mounted on the top of its respective flange 72 by means of suitable fasteners through holes 77. Each scraper blade 75 comprises a series of teeth 76 for breaking the ice layer from the cooled surfaces of the disc 70. The scraper blades are 10 hardened and tempered to withstand wear. The only major wear of the machine is the wear of ice against the scraper blades and the scraper blades 75 can be easily removed for replacement and / or sharpened again.

The supply of coolant to the discs 70 is shown in FIG. 16 and 17. A four-way distributor for liquid refrigerant is arranged at the inlet port 68 of the hollow shaft 71. The four-way distributor 15 comprises four copper distribution tubes 81-84, which are connected to channels in the discs 70. The lengths of the distribution tubes 81-84 from the inlet port 68 of their respective discs 70 is similar to provide the same pressure drop in the refrigerant supply to each disc.

The delivery end of each manifold 81-84 is received in a radial bore in the required portion of the hollow shaft 71, to which a corresponding disc 70 is mounted. Each disc 70 is mounted on a required portion by a tensioning nut 78. An inner electrical bore is formed in the center of each clamping nut 78 to provide an inlet chamber 73 between the delivery end of the respective delivery tube 81-84 and the channels of the associated disc. The refrigerant delivered through the tubes 81-84 fills the respective tubes 25 chambers 73, which are connected to channel openings 31 in each of the associated washers 70.

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Refrigerant flows through the channels 30 in each of the disks, thereby evaporating the agent to cool the disks. The evaporated refrigerant is withdrawn via the channel outlets communicating with a suction chamber 74 formed between the shafts 71 and the disc 70 at the elliptical opening in the tensioning nut 78. The suction chamber 74 is in communication with the interior of the hollow shaft 71 via slots 71 shaft 71. Cooling means are withdrawn from the interior 80 of hollow shaft 71 via outlet port 67 for delivery to the compressor of the cooling circuit.

In the foregoing, some embodiments of the present invention have been described, however many changes may be made without departing from the scope of the invention itself. Eg. For example, the ice-making machine may use a disc of a different shape 10 than the circular disc described, e.g. a hexagonal or polygonal disk.

The structure of the disc can be varied to include more than two layers bonded or brazed together, or the discs can be made by laminating a pipe coil between two flat metal discs.

In an alternative embodiment (not shown), the disc can be held stationary and the ice 15 can be removed by rotating blades. The blades may be provided with water application means on their adhesive side so that the leading edge removes the ice from the disc and the towing edge leaving a layer of water freezing at the time when the leading edge has fully turned. The water application means may take the form of a series of water spray nozzles or syringes.

Although the ice-making machine has been described with particular reference to ice cream making in flakes, the invention is not limited to this application. Eg. For example, ice-making machines of the present invention can also be used to make a juice product from fruit juice or fortifying agents. On a larger scale, the machine can also be used to make artificial snow.

Claims (12)

An ice making apparatus comprising at least one rotatable cooled disc (20) with internal refrigerant channels, means (15) located at a first position for applying liquid 5 to both sides of the disc (20), whereby at least some of the liquid is attached to both sides of the disc (20) and freeze as the disc (20) rotates, and means (20) for removing the frozen liquid from the sides of the disc (20) at a second position offset an angular rotation from the first position of the disc (20) rotational direction, characterized in that each disc (20) has a plurality of relatively narrow inner channels (30) for passing an evaporating refrigerant therethrough so that the evaporation of the refrigerant cools the disc (20) directly, which channels extend substantially over the entire disc. use party. Ice-making apparatus according to claim 2, characterized in that the channels (30) have substantially the same length. Ice-making apparatus according to claim 1 or 2, characterized in that each disc 15 (20) is laminated and comprises at least two disc parts (20A, 20B) in which open channels (30A) have been formed with the respective patterns which are mirror images of each other, which disc portions (20A, 20B) are bonded to each other to form the disc (20) and that the inner channels (30) are formed by the opposing open channels (30A). Ice-making apparatus according to one or more of the preceding claims, characterized in that the liquid is water and that the frozen liquid is removed from each disc (20) in the form of ice flakes. Ice-making apparatus according to one or more of the preceding claims, characterized in that the means for applying liquid comprise a reservoir (69) of the liquid in which each of the slices is partially submerged. ! DK 172831 B1 Ice-making apparatus according to one or more of the preceding claims, characterized in that the means for removing the frozen liquid comprise a pair of radial blade parts (52) arranged at each of the opposite sides of a disc. Ice-making apparatus according to one or more of the preceding claims, characterized in that at least one rotatable cooled disc (20) is a single cooled disc having a central opening in which a collar (22) is arranged, said collar (22). ) has a first row of radial bores (27) communicating at their inner ends (32) with a hollow shaft (18) disposed at one side of the collar and at their outer ends communicating with said inlets (31) to the channels (30) of the disk, and further has a second row of radial bores (29) with outer ends communicating with the respective outlets (33) of the channels (30) in the disk (20), and having inner ends communicating with another hollow shaft (21) inserted on the opposite side of the collar. Ice making apparatus according to one or more of claims 1-6, characterized in that the apparatus comprises a series of cooled discs (71) mounted on a common hollow shaft (71) with an inlet (68) and an outlet end ( 67), further comprising refrigerant delivery pipes (81-84) extending between the inlet end (68) of the hollow shaft (71) and the respective mounting of each of the washers (70) on the shaft (71), which delivery pipes (81-84) having substantially the same length, and at least one aperture in the shaft (71) at the rotation of each disc (70) on the shaft to provide fluid communication between the outlets of the channels of said discs and the inner shaft (71 ). An ice-making apparatus according to any one of claims 1 to 8, characterized in that each disc (20) functions as part of the evaporator of a cooling system. Ice-making apparatus according to any one of claims 1 to 4, characterized in that the means for applying liquid to the disc comprises liquid syringes (15) on both sides of the disc. DK 172831 Pg 16 A cooling disc (20) for use in an ice-making apparatus, comprising in a flat portion with a plurality of relatively narrow inner channels (30) for passage of relatively narrow inner channels (30) for passing a refrigerant therethrough, which channels (30) extending substantially over the entire portion of the disc, 5, characterized in that the planar portion comprises an inner centrally located portion with an inlet opening (31) in connection with the inner channels (30) at one end which serves to permit the insertion thereof. evaporative coolant into the washer (20), that the inner channels (30) generally guide from the inlet opening (31) outwardly toward the circumference of the washer (20) and then generally toward the inner portion, 10 and that the inner portion also has an outlet aperture (33). ) in connection with the inner ducts (30) at another end to permit removal of the refrigerant from the disc (20). Refrigeration disk according to claim 11, characterized in that the disk (20) is a laminate structure and comprises at least two parts (20A, 20B) in which open channels (30A) with the respective patterns which are mirror images of each other, which disk parts ( 20A, 20B) are bonded together to form the disc (20) and the channels (30) are formed by the opposing open channels (30A). r 1 "Ί