Process and equipment for manufacturing clear, solid ice of spherical and other shapes

The process and equipment, according to this invention, for manufacturing clear, solid ice of spherical and other shapes are capable of making clear ice balls and block ice of other shapes in the mold quickly, efficiently, and with effective energy utilization. This process is characterized in the steps of:

TECHNICAL FIELD

This invention relates to the process and equipment for manufacturing clear ice balls of the type frozen in the mold. These ice balls according to this invention are used for drinks to cool spirits and alcoholic beverages and are equivalent to those ice balls that are shaped by the bartender from clear ice by cutting it with artisan skill, or are shaped into balls with the grinder from block ice, put in a glass and served to the customer who has ordered a glass of alcoholic beverage. The size of ice balls ranges from too big one to put in the mouth to the balls as small as a piece of candy. These ice balls belong to a different field in use and size from the ice for shot blast or from small ice for instant cooling use, but are manufactured in the form. And as such, the process and equipment of this invention should also be applied to other types of shaped ice capable of being released from the mold.

There have been various proposals on the manufacture of ice balls of the type frozen in the mold.

For example, Japanese patent application (OPI) No. 1980-158461 described a water-freezing method, each as shown in FIG.18. Water is poured in a bag container1made of a synthetic resin having elasticity even at a low temperature. This container1is set stably in a hemispherical container2made of a metallic material, such as aluminum, having good heat conductivity. The container1is left to cool until water is frozen into ice.

Japanese patent application (OPI) No. 1984-49856 described a spherical container, such as shown inFIG. 19, comprising upper and lower hemispheres, which are tightly sealed by screws3that makes both halves engaged and tightened up with each other at the connecting portion. On top of the upper hemisphere is a hook-like pipe5for hanging the spherical container4. This pipe5is fitted vertically to the container4, and pure water6can be poured into the container4through the pipe5.

This container4is put inside a freezing tank with a setting at a freezing temperature near 0 degrees C. It is insisted that when the container4is swung in the freezing tank, water freezes without clouded core portion of the ice ball. The ice ball thus frozen can be taken out by separating the upper and lower halves.

Japanese patent application (OPI) No. 1992-15069 proposed a method of manufacturing golf balls of ice, which smash up on impact. As shown inFIG. 20a, a hemispherical lid7looks like an upper half of a hollow ball somewhat larger than a golf ball, obtained when the ball has been cut horizontally into halves. A wide ring8has a larger circumference than the container halves, is an integral part of the container9or the lower half of the ball, and is provided around the circular cross section. Both container halves7and9fit in with each other, as shown inFIG. 20b, and the upper lid7does not fall easily even when the combined container is turned upside down.

If these container halves7and9are fitted in water, then water10is filled inside the container as shown inFIG. 20b, and when the container is taken from underwater, no water runs out of the container.

It is insisted, therefore, that ice balls are obtained when this container with water inside is frozen.

However, in the case ofFIG. 18, it is contemplated that the cold temperature penetrates the water to be frozen in the order of A, B, and C, wherein A is a portion in contact with the metallic hemispherical container2, B is a portion in contact with atmosphere through the mouth of the bag container1; and C is the portions where the bag container1having insulating action exists between water and the freezing atmosphere. In that case, the upper and lower portions freeze first, and the middle portion, especially the core portion, is the last to be frozen, thus resulting in typical unclear ice having clouded core. This method would never create such ice as intended by this invention.

In the case ofFIG. 19, too, such ice as intended by this invention would never be manufactured because coldness penetrates water simultaneously over the entire surface of the spherical container. However the container is swung, the core portion would become clouded in the same way as in the case of FIG.18.

Likewise in the case ofFIG. 20, the ball container is left to freeze simultaneously over the entire surface, starting from the surface and ending at the core portion. Ice thus obtained is at the lowest level in its quality, and has no other choice but giving clouded core portion.

In contrast to the above conventional art, a proposal from Japanese patent publication No. 1994-89970 makes it possible to obtain clear ice. This method is shown inFIGS. 21 and 22. The ice-making equipment shown inFIG. 14comprises a plural number of ice-making cups11,11, a pair of covers12,12for each ice-making cup, a substrate, the first nozzle14, a coolant pipe15, and the second nozzle16,16.

The ice-making cup11is formed into a hemispherical shape of a certain diameter, from a metal plate, such as aluminum or stainless steel. The cups are arranged in lines and rows, in a state in which cups are turned bottom up, with the opening facing downward. These cups are fitted at given positions by connecting them with, for example, substrates13of the same material.

A coolant pipe15is tied around the bottom or the head portion of the ice-making cup15, as shown in FIG.21.

In the meantime, the covers12are made of a metal plate of the same material as used for the ice-making cup11, or made of a synthetic resin plate, and are formed into a pair of quarters of the sphere with the some diameter as the ice-making cup1l, as obtained by equally dividing a hemisphere similar to the ice-making cup11. The two quarters in a pair are fitted to the downside of the substrates13and are supported swingably through hinges17at positions corresponding to the ice-making cup11. In this case, the two covers12are fitted to the substrates13in such a relationship that the two covers are combined together to form a hemisphere and that the covers12and the cup11form a sphere.

Each hinge17is an attachment to the respective cover12and has the following structure: Each of distorted tetragonal tabs has a pinhole bored through the tab and is protruded like an ear from the central part of each lateral periphery of the quarter of the sphere. Both tabs are fitted to the substrate13by engaging them with the fittings suspended from the substrate13at corresponding positions and inserting a pin through each pinhole. In their closed state, the attached pair of covers12,12faces each other and comes in contact with each other right under the ice-making cup11. Both covers12,12are movable in the opposite directions to leave each other, and in their open state, the lower hemisphere breaks to make the mouth wide open.

The covers12,12are provided with an opening18having a certain diameter at the central, lowest part of vertical periphery of each quarter of the sphere. Each quarter has a half circle for water injection so that in the closed state, both quarters form a circular opening18at the bottom.

The hinges17of the covers12,12are provided each with a spring19, such as a coil spring, which acts a force on each cover to keep both covers12,12closed during the ice-making operation.

The process of ice-making operation is shown inFIGS. 22ato22d. The ice-making cup11is cooled to a low temperature by the coolant pipe15. Meanwhile, raw water for ice making use is spurted from the lot nozzle14and is shot into the ice-making cup11through the opening8(FIG. 22a). The water to be iced spreads over the inner surface of the ice-making cup11and the covers12,12. Then water drips from the opening18and is collected into a water tank. After the water temperature has deceased, water is again sent to the water pump, and is spurted from the 1st nozzle14into the ice-making cup11.

In this way, an ice layer is formed first on the inner surface of the ice-making cup11, and later on the inner surfaces of the covers12,12. Therefore, the ice layer gets thick first on the upper part of the ice-making cup11. Then, ice gradually becomes spherical over time (FIG. 22b).

As soon as the ball surge leaves the inner surfaces of the cup and the covers, the self-weight of the ice ball is automatically dispersed on the pair of covers12,12. As this self-weight overcomes the force of the spring19, the ice ball begins to drop downward. With the covers12,12forced to open wide, the ice ball completely breaks away from the ice-making cup11and the covers12,12, and drops into an ice-receiving tank (not shown) (FIG. 22d). In this system, raw water for ice making is not sealed inside a mold from the beginning, but is ejected therein serially to form thin laminates of ice. Like icicles, this ice ball can be clear to the core.

The proposal of Japanese patent publication No. 1994-89970 makes sure of clear ice ball manufacture, but it has the following drawbacks:

(1) After raw water is ejected, water is collected except for the iced portion, and is re-jected. In other words, water is recycled and reused. Because of this recycling, the opening18is clogged up with ice before round ice is completed. (Since recycled water tends to have a temperature at which water is frozen easily, the opening18begins freezing and clogging.) Eventually, it seems that solid block of ice fails to complete.

(2) It is reported that freezing takes place not only in the ice-making cup11equipped with the coolant pipe15, bat also on the covers12,12. It means that cooling is necessary for the space under substrates13where there are the covers12,12and therefore that strong freezing equipment is required for this purpose. As regards the ice-making cups11, the coolant pipe15is inefficient because it is tied around the head portion of the cup11, and a major part of the pipe15is exposed to air. Enormous energy is thus required to cool both of the ice-making cup11and ambient air surrounding the covers12,12.

(3) This enormous energy is not utilized efficiently. It is rather wasted because the ice-making process requires discontinued operation, energy loss, and repeated release of energy. For example, after ice balls are formed within the cup11and the covers12,12, hot gas is passed through the coolant pipe15. In addition, water of normal temperature is ejected onto the covers12,12from the nozzles16. Then, when ice-making process resumes, the coolant pipe15and the covers12,12have to be cooled again. This is inefficient utilization of heat.

The object of this invention is to provide a new means of manufacturing clear ice balls by forming laminates of ice inside the mold so as to ensure that many, clear ice balls can be mass-produced reliably and that input energy can be utilized efficiently. In addition, ice of other shapes can be obtained by changing the shape of the ice-making cup and the covers.

DISCLOSURE OF THE INVENTION

The means of achieving the above-described object comprises a process for manufacturing clear, solid ice of spherical and other shapes, which process is characterized by the steps of:a) preparing a mold for making ice bails and block ice of other shapes, which comprises an upper mold made of an insulating material and provided with a vertical injection hole drilled therein and a water-jet nozzle fitted in the hole; and a lower mold made of a water-freezing block having coolant pipe embedded therein;b) preparing for a shaped lid of a hemispherical or different shape made of an insulating sheet, said lid having a shape corresponding to the surface shaped for the upper mold and being provided with a bottom flange and a cylinder for being fitted into the vertical injection hole; and a shaped cup of the same insulating sheet, which similarly corresponds to the shaped surface of the lower mold and is provided with a top flange;c) assembling both halves of the mold after the domed lid (or the cover having plural lids) and the cup (or the tray having plural cups) have been attached tightly to each other and placed in the mold;d) then, keeping the liquid to be frozen cooled at a predetermined temperature and spraying the liquid intermittently in the direction of the water-freezing block that has been cooled to a predetermined freezing temperature;e) repeating the spraying operation to freeze the sprayed liquid in the tray, layer by layer, until clear ice balls or block ice of other shapes are formed; andf) disassembling the halves of the mold under the ice-releasing effect, which the ice container has on the ice-making mold, and immediately taking out the shaped ice balls or the block ice of a different shape.

The equipment for manufacturing clear ice balls and the block ice of other shapes comprise:a mold for molding ice balls and block ice of other shapes, which comprises an upper mold made of an insulating material having a vertical injection hole drilled therein and a water-jet nozzle fitted in the hole and connected to an intermittent injection mechanism; and a lower mold made of a water-freezing block having coolant pipe embedded therein; andspherical containers or the containers shaped otherwise, which comprise a domed lid or the lid of a different shape made of an insulating sheet, said lid having a shape corresponding to the surface shaped for the upper mold and being provided with a bottom flange and a cylinder for being fitted into the vertical injection hole; and a Shaped cup of the same insulating sheet, which similarly corresponds to the shaped surface of the lower mold and is provided with a top flange.

There are two types of spherical containers. A type is a container divided into upper and lower halves. The upper half or the domed lid has a shape attachable tightly to the surface shaped for the upper mold and is provided with a bottom flange and a cylinder for being fitted into the vertical injection hole. The lower half or the hemispherical cup has a shape attachable tightly to the surface shaped for the lower mold and is provided with a top flange. The other type is a container divided vertically into the right and left halves. The lower half portion of the combined container is attached tightly to the surface of a hemispherical or another shape, and is provided with a cylinder for being fitted into the vertical injection hole and with a side reinforcing flange.

The above-described spherical container is made of a resin sheet material, such as styrol, or a metal plate material, such as aluminum, which is hard and highly heat-conductive.

When water is injected into the shaped container on the cooled water-freezing block, the injected water is soon frozen under the freezing atmosphere after a very short period of retention because the amount is small.

This fast freezing ability is convenient when juice and other solutions are to be frozen, because juice is frozen before separation will take place.

Ice on the bottom of the spherical container receives coldness from the water-freezing block, and ice itself becomes an ice-cold source, which freezes up at once the intermittently injected water sprayed on the frozen water. Like icicle formation, thin clear laminated ice is obtained by this most reliable, most efficient ice-making method. The upper mold is a heat-insulating material that confines coldness of the lower part. This mechanism is energy saving and economic because the entire space in the spherical container to be filled with ice can be cooled by means of only the water-freezing block.

The water-freezing block can be a big one if the block is designed to give a thick configuration. When another round of freezing operation starts, a thick freezing block is advantageous because the previously produced ice does not affect the thick block even if coldness is drawn therefrom, and so the subsequent ice can be made quickly. (Ice cold source need not be operated more powerfully than usual.)

An insulating sheet (a container) stands between the inner surface of the mold and ice to prevent ice from coming in contact with the water-freezing block. Because this insulating sheet serves as a mold-release agent, it is easy to release ice from the mold and to take ice out of the mold (with no requirement for heating).

In the case of a container made of a resinous sheet material, such as styrol, the container serves as a packaging material after ice has been made. As a commercial product, ice is kept packed in the container. The container to be divided into two halves is convenient when ice is taken out. In the case of a metal plate container, it belongs to the mold. After ice has been taken out, the container is put back into the mold.

It is contemplated that a resinous sheet material such as styrol, may have less tight contact with the mold because of its flexibility even if the resinous sheet has good molding precision. Because of a heat-insulating air layer existing inside the container as an intervention and the resistance of the resin itself to thermal conductivity, it is possible to think of a fear that the surface of sprayed water may not have a predetermined freezing temperature and therefore that precise ice production cannot be expected. There is no such concern in the case of a metal plate material, such as aluminum, which is a hard and good thermal conductor. This is because metal plates secure thermal conductivity by way of the unavoidable contact with the water-freezing block, ie., the cold source, even if the container has less molding precision and incomplete contact with the mold. And there may happen non-uniform temperature distribution among separately configured freezing blocks, and it may become impossible to make uniform ice. Even if such a problem occurs, non-uniform temperature distribution among blocks can be solved conveniently by inserting a thermally conductive plate, such as an aluminum plate, between two adjacent freezing blocks in a manner that the plate can be contacted with each spherical container.

PREFERRED EMBODIMENT OF THIS INVENTION

This invention is further described in the case of ice balls, now referring toFIGS. 1-17.

FIG. 1shows an overall configuration of the equipment for making a clear ice ball in the preferred embodiment of this invention (the mold and the spherical container of the type divided into upper and lower halves), in the state in which ice has been completed. The ice ball20is packed in the container21, which in turn is abut in the mold24for making ice balls. This mold24comprises an upper mold24aand a lower mold24b. The former is made of a heat-insulating material and is provided with an injection nozzle22that is connected to an intermittent injection mechanism; the latter is the water-freezing block26, in which the coolant pipe25is embedded (InFIG. 1, the pipe is located right under the mold).

InFIG. 1, a rubber gasket layer27is disposed preferably on the underside of the upper mold24a, and is used for the sake of completeness to put the container exactly between both halves of the mold24, while holding tight the flanges of the container21.

A heat-insulating layer28serves to prevent coldness from escaping through the surfaces of the water-freezing block26. Naturally, this layer should be disposed not only on the bottom of the mold24, but also on the sides.

Because of this heat-insulating layer28, the coldness generated by the water-freezing block26is entirely directed toward the space for the water to be frozen inside the mold24.

The water-freezing block26has round holes29dug in the lower mold, and the upper mold24athat covers the water-freezing block26is provided with domes31, which correspond in shape to respective round holes29.

As seen, many round holes29are disposed in a lattice pattern on a larger-size, water-freezing block26′. Right under the round holes29run the rows of grooves for embedding the coolant pipes24.

FIG. 3shows one of the above-described spherical containers21.

The domed lid21aand the hemispherical cup21bare provided respectively with the bottom flange32and the top flange33. A vertical cylinder23ais disposed on top of the dome and is fitted into the vertical injection hole23to allow for the passage of injected water.

FIGS. 4 and 5show a cover21a′ and a tray21b′ of an integral type having many domed lids and cups, respectively, for use with the larger-size, water-freezing block26′.

FIG. 4shows a cover21a′ of the integral type prepared by the vacuum molding;FIG. 5shows a tray21b′ of the integral type having hemispherical cups shaped therein.

FIG. 6Shows an intermittent injection mechanism35, which is connected to the above-described water injection nozzle22.

InFIG. 6, raw water tank36sends water into circulating water pipe37. On the way, water passes through filter38, constant pressure pump39, the suction adjusting pressure valve of this pump39, and air supply valve40, respectively, for the filtration of suctioned water, the setting of pressure inside the pipe27, and the mixing of air into water (so water may have a mild taste). Circulation of raw water is preferred to prevent liquid mixtures from being separated.

Branching pipes41are connected to each injection nozzle22by way of distributor37′. A tube pump42is disposed halfway on each branching pipe41to supply water in an intermittently fixed amount.

FIGS. 7 and 8show an example of the plural tube pumps42shown in FIG.6. The pushing mechanism used for the tube pumps43of this invention stands face to face with an arc surface44of a pump mount45for accommodating the tube pumps46. As shown inFIG. 7, this pushing mechanism is a rotating body comprising a given number of one-point pressure rollers49disposed around a shaft48but not in contact with the circumference thereof. The shaft48extends from one bracket47to the other bracket47, surrounded by one-point pressure rollers49, which are kept at satellite positions by each roller shaft49a.

However, since the pushing mechanism (one-point pressure rollers49) has no pinch roller configuration, it does not drag anything that comes in contact, and rotates passively in response to an added force.

A plural number of tubes are disposed between the pump mount45and the rotating body50, with the tube upstream being fixed, and the downstream unfixed, as not to bend the tubes.

In addition, as shown inFIG. 8, a thin foil material51is disposed between the tubes46and the rotating body50, with upstream fixed, and downstream unfixed. This foil has high durability, flexibility, and slidability against rollers.

If a commercially available foil product is used, various tests with aqueous solutions indicate that a stainless steel foil of less than 0.9 mm thick is preferred for ordinary tubes. (It was confirmed from various tests that at a thickness of 0.1 mm or more, the dragging effect is not solved completely but that at a thickness of less than 0.9 mm, the dragging effect could be eliminated for the first time. It is contemplated that this side effect is caused from the fiction between the foil and the tubes46at the points of contact with the one-point pressure rollers49if the foil has some rigidity and no certain level of flexibility. The one-point rollers49are considered effective to some extent to eliminate the dragging effect because these rollers49have a free-rotating configuration. However, for perfect elimination of this side effect, it is a key point that the foil has a thickness of less than 0.1 mm because at this thickness, the foil is as flexible as to able to prevent friction from being generated.)

As shown inFIG. 8, four one-point pressure rollers49are disposed at an equivalent interval to ensure that at least two rollers stand face to face with the arc surface. This arrangement is suitable because a fixed quantity of liquid can be measured out precisely between two rollers49,49, and is carried to respective spherical containers.

However, under the circumstances in which the upper mold24ais separated from the lower mold24b, as shown inFIG. 9, the hemispherical cup21band the domed lid21aare fitted tightly into the round hole29and the dome31, respectively.

As shown inFIG. 10, the upper mold24ais then assembled with the lower mold24b. The domed lid21aand the hemispherical cup21bare pressed to each other as the flange32is put on top of the flange33. Thus, joint seal is completed for the space inside the spherical container21.

The water-freezing block26has been fully cooled by means of the coolant pipe25to a temperature of −3 to −6 degrees C. that is suitable for clear ice. Raw water34(10 degrees C. or less) is then intermittently injected from the injection nozzle22. (The end of the nozzle22is disposed at a certain height above the freezing level so as to prevent the nozzle from being clogged due to the contact with the top of frozen ice.)

The intermittently injected raw water34(about 1.8 ml) is almost instantaneously frozen and turns into ice34′ of a single crystal, one shot after another, while keeping this level of amount. Backed up by the water-freezing block26, ice itself serves as a strong cold souse. When subsequent water is intermittently injected, the water equally turns into ice of a single crystal, which are piled on, one layer after another.

As detected by a level sensor or as calculated previously, a certain level of freezing operation is measured out, and the injection of raw water34is discontinued at that point.

Then, the upper mold24ais withdrawn, as shown in FIG.12. (Because of the existence of the domed lid21a, there is no contact between the upper mold24aand ice20. Thus, the withdrawal is quickly carried out)

Similarly, the ice ball20can be easily taken out of the lower mold24bbecause ice is packed in the spherical container21.

The ice ball20packed in the spherical container21of a resinous sheet material such as styrene, is shipped as a commercial product merely by cutting or bending the cylinder23a. In use, it is only necessary to separate between the flange32and the flange33to take out the ice ball20from the spherical container21. This ice ball package is advantageous in its quite easy handling.

If the spherical container is made of a metal plate, such as aluminum, then the container is dipped in water to remove ice that has covered the container. After ice is taken out, the container is put back in the mold.

FIGS. 13-15show the spherical container21′ of the vertical separation type. The container comprises right and left halves21′aand21′b, which are provided with a reinforcing flange F.

FIGS. 16 and 17show pairs of upper and lower uniting rings L of the same shape for attaching the two halves of the spherical containers21′.FIG. 16shows the uniting rings of the integral type;FIG. 17is an enlarged view of a uniting ring L. As shown, ring hole La forms a container seat, and slits S are cut through the ring hole La to insert the above-described reinforcing flanges F (InFIG. 17, flanges are disposed in two directions to allow for possible selection). The slits S are cut so as to avoid interference from the next slits.

The uniting rings L, L cover the container from both up- and down-sides, and tighten up the two halves of the spherical containers21′ against the container diameter.

If the uniting rings L of the integral type are made of a good conductive material, such as aluminum, the spherical containers21′ are linked with one another, and are kept at the same temperature, which is preferable for the convenience of ice quality control.

Possibility of Industrial Utilization

This invention in the above-described configuration has the following effects.

(1) Ice can be mass-produced efficiently due to instantaneous freezing of injected water and easy takeout of ice right after water has been frozen.

(2) In the conventional art, input energy for cooling turned out to be a hindrance when ice was released from the mold. Additional heating energy had to be required for the release of ice, and then energy became necessary for freezing water again. In this invention there is no such wasteful utilization of energy. The cooling energy can be utilized effectively for the subsequent rounds of freezing operation. This ice-making method is ideal from the energy efficiency point of view.

(3) The spherical containers of this invention are convenient for combined use as a molding material and as a packaging material (in the case of the resinous sheet material). In addition, these containers make it unnecessary to heat and melt ice surface for the release from the ice-making cup, as found necessary in conventional art. These containers are ultimately rational as they can be used also as the release material. They are also convenient for taking out ice balls because the spherical containers can be divided into two halves.

(4) Ice according to this invention is not limited to the spherical shape. Clear ice of other desired shapes, such as ice cubes, is obtained if the mold is replaced with another one for different shaped ice, provided that the ice containers can be separated into upper and lower halves.

(5) It is possible to use various solutions, instead of fresh water, as the raw water. If raw water is a liquid or something else to qualify spirits with, then the spirits with shaped ice require no additional water. Furthermore, such drinks as coffee, tea, and juice can be turned into shaped ice.