The present invention relates to a flow-type ice maker that makes ice in an ice-making rack by allowing ice-making water to flow into the ice-making rack. The invention particularly relates to a structure of a refrigerant pipe of the ice maker.
A flow-type ice maker is a device that makes ice by allowing ice-making water to flow continuously into an ice-making rack. For example, a device described in WO 2014/105838 filed by the present applicant has been known. This device makes ice on a surface including the outer periphery of a refrigerant pipe, by allowing ice-making water to continuously flow into an ice-making rack supporting the refrigerant pipe. Since this device makes ice directly on the outer periphery of the refrigerant pipe, it has high heat-exchange efficiency.
In a conventional ice maker, a tinned copper pipe is used as a refrigerant pipe. Although this refrigerant pipe has high heat-exchange efficiency, it has a problem that the tin plating easily comes off to expose the copper. Since the refrigerant pipe needs to be replaced when copper is exposed at a contact point with ice, maintenance of the ice maker has required time and effort.
An objective of the present invention is to provide a flow-type ice maker including a refrigerant pipe whose contact surface with ice is kept unaffected over a long period of time, and that has high thermal conductivity. Another objective is to provide a flow-type ice maker that can reduce the radius of curvature of a curved part of the refrigerant pipe.
The present inventors have found that the above problem can be solved by covering the outer periphery of a pipe made of copper or aluminum with stainless steel, and using the pipe as a refrigerant pipe of a flow-type ice maker. The inventors also have found that high heat-exchange efficiency can be achieved by forming a groove on a pipe inner part of the refrigerant pipe. The present invention has been completed according to the above knowledge.
The present invention that solves the above problem will be described below.
[1] A flow-type ice maker including:
an ice-making part configured by
an ice-making water feed pipe feeding ice-making water to the ice-making water flow part, wherein:
the refrigerant pipe has a curved part; and
an outer periphery of a pipe made of any one of copper and aluminum is covered with stainless steel.
[2] The flow-type ice maker described in [1], in which the refrigerant pipe of the curved part has an radius of curvature that is twice to ten times the pipe outer diameter of the refrigerant pipe.
[3] The flow-type ice maker described in [1], in which the refrigerant pipe has a pipe outer diameter of 8 to 20 mm.
[4] The flow-type ice maker described in [1], in which in the refrigerant pipe, a ratio of a thickness of the pipe made of any one of copper and aluminum to a thickness of the pipe made of stainless steel is 1:0.2 to 1:2.
[5] The flow-type ice maker described in [1], in which the refrigerant pipe is a refrigerant pipe having a groove formed on a pipe inner wall.
[6] The flow-type ice maker described in [5], in which the groove formed in the refrigerant pipe is a plurality of helical grooves.
In the flow-type ice maker of the present invention, the refrigerant pipe is formed by covering the outer periphery of a pipe made of copper or aluminum with stainless steel. Hence, the contact surface with ice is less likely to deform even after use for a long period of time. Accordingly, the ice maker can be maintained easily. Moreover, since the outer periphery of a pipe made of copper or aluminum is covered with stainless steel, bending is made easier, and the radius of curvature of the curved part can be reduced. Hence, the ice maker can be reduced in size. Additionally, by forming a groove in the pipe inner wall of the refrigerant pipe, occurrence of a laminar flow on the pipe wall part can be suppressed, and heat-exchange efficiency can be enhanced. In the flow-type ice maker of the present invention, the outer peripheral surface of the refrigerant pipe is configured by stainless steel, whereas the pipe inner part is configured by copper or aluminum. Hence, the groove can be formed easily.
Hereinafter, an example of the present invention will be described in detail, with reference to the drawings.
Connection members 12a and 12b for connecting a plurality of ice-making cells are formed in the ice-making cell 11a. The plurality of ice-making cells is connected by the connection members.
First, ice-making water is fed into the box of the ice-making water flow part 17. The fed ice-making water flows into the ice-making rack 11 through the holes 31. A part of ice-making water that has flowed into the ice-making rack 11 comes into contact with an outer peripheral part of the refrigerant pipe 13 through which a refrigerant circulates, and freezes. The rest of the ice-making water flows into lower refrigerant pipes. Accordingly, ice is formed along the shape of the ice mold 15, in the outer peripheral part of the refrigerant pipe 13. In
The ice-making rack 11 is formed of a resin material. The resin material is not particularly limited, as long as it is a resin that complies with the Food Sanitation Law. Examples of the resin include polyacetal (POM), polycarbonate (PC), ethylene bis stearamide (EBS), and polypropylene (PP).
The refrigerant pipe 13 is a pipe having a circular or oval cross section, and is formed by covering the outer periphery of a pipe made of copper or aluminum with stainless steel.
The refrigerant pipe 13 is formed such that ice-making water comes into direct contact with the metal surface of the refrigerant pipe 13. That is, since the refrigerant pipe 13 is not covered with resin or the like, the refrigerant pipe 13 has high heat-exchange efficiency. Moreover, since the resin material (ice-making rack) and the metal material (refrigerant pipe 13) are combined, ice is held securely in the ice-making rack at the time of ice making, and the ice is separated easily at the time of separation from the mold. Ice made by the ice maker of the present invention is preferably in contact with the ice-making rack (resin part) and the refrigerant pipe (metal part) at a rate of 1:0.1 to 1:10, and is more preferably in contact therewith at the rate of 1:0.5 to 1:2. Since the ice is held by being in contact with the parts at this rate, both high heat-exchange efficiency and separability can be achieved.
The ice maker of the present invention is characterized by using, as the refrigerant pipe 13, a pipe formed by covering the outer periphery of a pipe made of copper or aluminum with stainless steel. The refrigerant pipe is preferably a pipe formed by covering the outer periphery of a pipe made of copper with stainless steel.
The pipe outer diameter of the refrigerant pipe is preferably 8 to 20 mm, and is more preferably 10 to 18 mm.
Additionally, in the refrigerant pipe used in the present invention, the ratio of the thickness of a pipe (inside part) made of copper or aluminum to the thickness of a pipe (outside part) made of stainless steel is preferably 1:0.2 to 1:2, and is more preferably 1:0.8 to 1:1.7. When the thickness of the outside part is smaller than 0.2 times the thickness or exceeds twice the thickness of the inside part, the outside part is likely to crack. The crack is likely to occur particularly during bending. Moreover, even if the refrigerant pipe can be bent, since the refrigerant pipe circulates a low-temperature refrigerant when ice is made, and circulates hot gas when the ice is melted, a crack may occur due to heat shock. Furthermore, when the thickness of the outside part exceeds twice the thickness of the inside part, heat-exchange efficiency deteriorates.
More specifically, the thickness of the inside part is preferably 0.2 to 0.8 mm. The thickness of the outside part is preferably 0.1 to 0.8 mm.
The refrigerant pipe 13 has a plurality of curved parts. A radius of curvature of the curved part of the refrigerant pipe is preferably 2 to 10 cm. The radius of curvature of the curved part is preferably twice to five times the pipe outer diameter of the refrigerant pipe, and is more preferably three to four times the pipe outer diameter of the refrigerant pipe. When the radius of curvature of the curved part exceeds five times the pipe outer diameter of the refrigerant pipe, the ice maker becomes large. When the radius of curvature of the curved part is less than twice the pipe outer diameter of the refrigerant pipe, the curved part of the refrigerant pipe is likely to crack.
Although the stainless steel is not particularly limited as long as it is suitable for use in food, in consideration of processability, SUS410, SUS430, SUS304, and SUS316 are preferably used.
Layers of such a two-layer refrigerant pipe 13 need to be brought into intimate contact with each other at the interface, to maintain heat-exchange efficiency. Hence, the refrigerant pipe 13 is preferably formed as one unit. That is, the pipe made of copper or aluminum and the pipe made of stainless steel are preferably in intimate contact with each other and integrated, with no gap or adhesive, for example, in between. Such a two-layer pipe can be produced in a similar manner as a conventionally available clad pipe.
It is preferable that a groove is formed on a pipe inner part of the refrigerant pipe 13. Such a groove can suppress deterioration in heat-exchange efficiency due to a laminar flow generated on a pipe inner wall part. Further, the groove increases the surface area of the pipe inner wall, and can thereby enhance heat-exchange efficiency even more. The groove is preferably formed into a helical shape. The helical groove is formed such that the lead angle relative to the pipe axis is preferably 5 to 45 degrees, and more preferably 10 to 30 degrees. Although the number of grooves is not particularly limited, it is preferable that 10 to 100 grooves are formed in the pipe inner peripheral part.
Although the depth of the groove is not particularly limited, the depth is preferably 0.03 to 0.6 mm, and more preferably 0.05 to 0.5 mm.
An ice-making water collection part that collects ice-making water flowing in from the ice-making rack 11 may be joined to a lower part of the ice-making rack 11.
The ice-making part 10 is placed in an ice-making room kept at a low temperature. The inside of the ice-making room may be cooled by circulating a refrigerant through the refrigerant pipe 13, or a separate cooling system may be provided.
Hereinafter, the present invention will be described in further detail by use of an example. This example indicates that the ice maker of the present invention has an equivalent ice-making capacity as an ice maker using a conventional refrigerant pipe.
The device illustrated in
As the refrigerant pipe, a two-layer pipe including a 0.5 mm thick copper and a 0.3 mm thick stainless steel was used. On an inner wall of the refrigerant pipe, 60 grooves having a 13 degree lead angle were formed. An ice maker was built with other conditions being the same as Example 1. As a result, the average ice-making time was 22 minutes 38 seconds, the average ice removal time was 1 minute 42 seconds, and the daily performance was 106.1 kg. In this ice maker, no change was observed in the outer surface of the refrigerant pipe, even after repeated ice making.
As the refrigerant pipe, a tinned pipe including a 1.0 mm thick copper was used. On an inner wall of the refrigerant pipe, 60 grooves having a 15 degree lead angle were formed. An ice maker was built with other conditions being the same as Example 1. As a result, the average ice-making time was 21 minutes 22 seconds, the average ice removal time was 1 minute 30 seconds, and the daily performance was 103.5 kg. After this refrigerant pipe was used for two years, the surface tin plating came off and exposed the internal copper, and the copper lost its metallic luster and turned brown.
Number | Date | Country | Kind |
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2018-078037 | Apr 2018 | JP | national |
Number | Name | Date | Kind |
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5438839 | Wardle | Aug 1995 | A |
20140182314 | Hoti | Jul 2014 | A1 |
20150136361 | Gregory | May 2015 | A1 |
Number | Date | Country |
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1991121365 | Dec 1999 | JP |
2004125385 | Apr 2004 | JP |
2015135217 | Jul 2015 | JP |
2018039043 | Mar 2018 | JP |
2014105838 | Jul 2014 | WO |
Number | Date | Country | |
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20190316823 A1 | Oct 2019 | US |