JP2007225144A - Ice generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ice generator capable of increasing production concentration of salt water sherbet ice, eliminating abnormal sound and abnormal vibration, and lowering salinity concentration of material water. <P>SOLUTION: A scraper 5 of this ice generator is changed in its shape to increase the concentration of produced ice, and simultaneously provided with a sherbet ice flow channel 16 of low resistance inside of the ice generator, and a dynamic pressure is applied to the fluid by using an auxiliary pump blade 15. Further a hardness of a scraper material is increased, and simultaneously a tip edge for scraping off the ice has the sawtooth shape to lower a lowest allowable salinity concentration of the material water. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an ice generator for a sherbet ice production apparatus used for maintaining freshness in the field of marine products and agricultural products.

A general saltwater sherbet ice manufacturing apparatus will be described with reference to FIG. 1 is an ice generator for generating salt water sherbet ice, 2 is a rotor for scraping the sherbet ice generated on the ice making surface (31 in FIG. 3) of the evaporator 3 by a scraper 5 disposed around it, 3 is a freezer An evaporator for evaporating the refrigerant liquid supplied from the machine 7 to cool the salt water, 4 is a salt water flow path inside the ice generator, 5 is an inner cylinder ice surface of the evaporator 3 attached to the rotor 2 (31 in FIG. 3) ) Scraped off the generated sherbet ice, 6 is a geared motor that drives the rotor 2, 7 is a refrigerator, 8 is a tank for storing sherbet ice, 9 is an evaporator 3 of the ice generator 1 from the refrigerator 7. A refrigerant liquid pipe for supplying the refrigerant liquid, 10 is a refrigerant gas pipe for returning the refrigerant gas evaporated in the evaporator 3 to the refrigerator 7, and 11 circulates salt water between the tank 8 and the ice generator 1. Pump, 12 feed pipe to the generator over 1 saltwater, 13 is a return pipe to the tank from the ice generator over the brine.

Next, the operation will be described. First, salt water as a raw material for sherbet ice is filled in the tank 8, and the pump 11 is operated to supply salt water to the ice generator 1 and circulate between the tank 8. When the refrigerator 7 is operated in this state and the refrigerant is supplied from the refrigerant liquid pipe 9 to the evaporator 3, the salt water is gradually cooled and the temperature is lowered. When the temperature falls below 0 ° C., the water in the salt water begins to freeze at a temperature corresponding to the salinity concentration. For example, when salt water has an initial salinity (mass ratio) of 2.5%, ice formation begins at minus 1.43 ° C. As ice is formed, the water content in the salt water decreases, the salinity increases, and at the same time the ice temperature decreases. For example, if the ice concentration (mass ratio of ice to the initial salt water mass) is 30%, the salinity of the salt water is 3.5% and the freezing temperature is minus 2.11 ° C. When water contains salt, ice crystals do not become coarse and form a sherbet. As the proportion of ice increases, the viscosity of salt water containing ice, that is, salt water sherbet ice, increases the flow resistance, and the current value of the geared motor that drives the rotor 1 also increases. When the ice concentration reaches a certain value, for example 40%, the motor is overloaded and tripped by the overcurrent protection device, so the sherbet ice production is stopped when the previous current value is low to avoid overloading. . The lower the salinity of the raw material water, the higher the freezing temperature. In the case of hard ice, the scraper 5 cannot be used to scrape the geared motor because the rotor 2 is locked. Conventional ice generators have a salt concentration of about 2.5% as the lower limit, and salt water sherbet ice cannot be made if the salt concentration is lower than this.

The details of the conventional sherbet ice generator will be described with reference to FIGS. In FIG. 5, 2 is a rotor of an ice generator, 5 is a scraper that scrapes off ice, 17 is a support bracket of a support bar 18 that supports the scraper 5, 18 is a support bar of the scraper 5, 19 is a shaft of the rotor 2, and a geared motor 6 Connected to. In FIG. 6, 2 is the rotor of the ice generator 1, 30 is an edge that scrapes off the ice at the tip of the scraper 5, and 31 is an inner cylinder ice surface (scraper 5 side) of the evaporator 3 of the ice generator 1. Is generated. Reference numeral 32 denotes the front side of the scraper 5, and in FIG. 7, reference numeral 33 denotes a recess for attaching the scraper 5 to the support rod 18.

Next, the operation will be described. When the temperature of the salt water is higher than the ice temperature, the salt water is cooled by the inner cylinder ice surface 31 of the evaporator 3 and the temperature is lowered. When icing starts, the scraper 5 attached to the rotor 2 of the ice generator 1 scrapes off the ice produced on the inner cylinder ice surface 31 of the evaporator 3. The scraped ice accumulates on the front surface 32 of the scraper, and at the same time, is pushed away by the water stream circulating from the lower side of the rotor 2 to the upper side in the axial direction and goes out of the ice generator 1 to the tank 8.
German Patent Nr. 101 13 395 JP2002-22324 JP2003-148841 JP2004-239489 JP2002-350017 JP2002-364954 JP2003-42611 JP2000-121285

Since the conventional sherbet ice generating apparatus is configured as described above, when the ice concentration increases and the viscosity of the sherbet ice increases, the resistance of movement increases and the ice accumulated in the relatively narrow front surface 32 of the scraper 5 is removed. The water pressure required to flush away increases. In the case of a centrifugal pump with a head of about 30M, an ice concentration of about 35% is the limit that can be swept away. If the ice concentration exceeds 35% and the resistance to movement reaches the limit of the pressure that can be pushed by the pump, there will be no water flow circulating through the generator 1. At this time, since the ice making surface 31 of the evaporator 3 is cooled in a state where water is accumulated, the thickness of the ice rapidly increases, the rotor 2 is locked, and the geared motor trips. Once in the locked state, the internal ice cannot be removed by the water flow, and the rotor 2 is removed from the ice generator 1 and the ice must be removed. Although it is effective to use a positive displacement pump instead of a centrifugal pump to increase the ice concentration limit, the cost of the pump is very high. Further, in the case of a positive displacement pump, since the ultimate pressure exceeds the pressure limit of the rotor 2, it is necessary to install a pressure protection device so that the water pressure does not exceed a certain pressure. If this is not installed, the rotor 2 may be pressure cramped (crash) and the rotor may be destroyed. In order to avoid these problems, it is possible to limit the ice concentration to a low level. However, if the ice concentration is low, the performance as sherbet ice is lowered, and a claim is generated from the side using the ice. From a practical point of view, it is desirable that the ice concentration be 40% or more using a centrifugal pump.

The lower limit of the salt concentration at which ice can be generated with the conventional ice generator 1 is 2.5%. At lower salinity, the ice becomes hard and cannot be scraped with a conventional scraper. The conventional scraper material not only has a low hardness, but also has a tip shape that is linear in the longitudinal direction, so that when it comes into contact with ice, it strikes uniformly at the same time, so there is no concentration of force and the force to break ice is dispersed and weak. If it cannot be scraped off, the ice will become thick and the rotor clearance will disappear, causing an abnormal contact sound and causing the rotor to lock. As a result, an overcurrent trip of the geared motor is reached and ice making operation is stopped. The ice making cost decreases as the salinity can be reduced (in the case of artificial salt water, the amount of salt used is reduced), and even if it is judged from the fact that the salinity of about 1% is the most preferable concentration for cooling and storing fresh fish, It is desirable that the salinity of salt water is lower than 2.5%.

In addition, one of the reasons for lowering the ability to scrape ice is the poor followability of the scraper against the deviation of the roundness and straightness of the evaporator inner cylinder (the axial deviation of the center line). The length of the conventional scraper in the axial direction is about 200 mm, but if this length is not straight, the scraper will not be able to cope with roundness and straightness deviation, and the gap between the ice making surface and the surface. A gap is formed and the ice scraps are left behind. This scraped-off ice grows hard, causing abnormal noise and vibration during ice making, and reducing the life of the scraper.

The present invention has been made to solve the above-mentioned problems, and is an ice generator that can increase the production concentration of salt water sherbet ice and eliminate abnormal sounds and vibrations and make the raw water salt concentration thinner. Is to provide.

In the present invention, in order to achieve the above object, the ice pool on the front surface of the scraper is eliminated, and the scraped ice immediately leaves the scraper.

By providing a flow path of sherbet ice with low resistance between the scraper and the outer surface of the rotor, the sherbet ice that has been scraped and flowed in can be moved smoothly.

Furthermore, the axial flow blades that apply dynamic pressure to water are provided on the outer surface of the rotor so that the rotor can also function as an auxiliary pump during rotation, so that the sherbet ice can be moved easily.

In order to make it possible to scrape harder ice, the hardness of the scraper is increased (conventional hardness Rockwell R40 is raised to, for example, R117) and at the same time, the scraper scraping tip shape is changed to a sawtooth shape. As a result, the biting force into the ice by the sharp teeth was increased, and it became possible to scrape hard ice made from salt water with a low salinity.

The length of the scraper is reduced to half (about 100mm) or less than that of the conventional one, and the followability to the deviation of the roundness and straightness (centerline axial deviation) of the evaporator inner cylinder has been improved.

As described above, according to the present invention, it is possible to use raw material water having a lower salinity (1.5%) than that of the conventional (2.5%), and the ice concentration is higher than that of the conventional (35%) even if a spiral pump is used. (45%) Since sherbet ice can be obtained and abnormal noise and vibration can be prevented, an economical and reliable ice generator that can produce sherbet ice with high cost performance is realized. I can do it.

Embodiments of the present invention will be described below with reference to FIGS. 2, 3, and 4. FIG.

In FIG. 2, 15 is a blade of an auxiliary axial flow pump attached to the outside of the cylinder of the rotor 2, and 16 is a sherbet ice provided between the surface connecting the bottom of the scraper 5 (dashed line in FIG. 3) and the surface of the rotor 2. The flow path.
Others are the same as in FIG.

FIG. 3 shows a cross-sectional view of the state in which the rotor 2 according to the present invention is mounted on the inner cylinder of the evaporator 3 as seen from above. The scraper 5 is attached to the rotor by a support bracket 17 and a support rod 18. Since the scraper 5 can rotate around the support rod 18, it can cope with rotating roundness of the ice making surface of the evaporator inner cylinder. Since the auxiliary axial flow pump blade 15 is disposed in the flow path 16 of the sherbet ice on the outer circumference of the rotor 2, it applies dynamic pressure to the flow of the sherbet ice.

In FIG. 4, reference numeral 20 denotes a sharp tip of the scraper 5 having a sawtooth shape on the scraping side tip, and 21 denotes a receding edge following the tip. 22 is a tip opposite to the scraping teeth of the V-shaped scraper 5 as a whole, and this tip is attached with a slight clearance from the ice making surface 31 of the evaporator inner cylinder, and the tip 20 is lifted from the ice making surface. Is preventing.

The operation of the above configuration will be described below. When the rotor 2 rotates in a state where the temperature of the salt water is sufficiently lowered and the ice making state, the scraper 5 scrapes off the ice generated on the ice making surface 31 of the evaporator. At this time, the tip edge 20 first bites into the ice and breaks the ice, so that the retreating edge 21 following the tip can easily scrape the ice. Hard ice that spreads in a plane can be easily scraped after it is cracked once with such a sharp pointed hard tip edge. In this way, the lower limit of the salinity that can be iced, which was 2.5% in the past, can be lowered to 1.5%.

The ice scraped off by the scraper 5 flows inward and reaches the flow path 16 without staying along the slope of the scraper 5. In this flow path, there are few obstacles in the flow of the sherbet ice so that it flows smoothly. Further, the sherbet ice is given a dynamic pressure in the axial direction by the action of the auxiliary axial flow pump blade 15 and the flow is further accelerated. This makes it possible to push the 35% limit of ice concentration, which was difficult with a conventional centrifugal pump, to 45%.

The axial length of the scraper 5 is half that of the conventional scraper (about 100mm) or less, so the scraper follows the deviation of the roundness and straightness (centerline axial deviation) of the evaporator inner cylinder. The frequency of occurrence of abnormal noise and vibration is reduced.

General salt water sherbet ice generator Ice generator rotor in one embodiment of the present invention 1 is a cross-sectional view of an ice generator in an embodiment of the present invention. Scraper in one embodiment of the present invention Ice generator rotor in one conventional example Scraper arrangement in a conventional example Scraper in one conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ice generator 2 Rotor 3 Evaporator 4 Water flow path edge 5 Scraper 6 Geared motor 7 Refrigerator 8 Tank 9 Refrigerant liquid pipe 10 Refrigerant gas pipe 11 Circulation pump 12 Salt water supply pipe 13 Salt water return pipe 15 Auxiliary axial flow pump blade 16 Sherbet Ice flow path 17 Support bracket 18 Support rod 19 Shaft 20 Scraper tip edge 21 Scraper retracting edge 22 Scraper rear end 23 Scraper root 30 Conventional scraper tip 31 Evaporator inner cylinder ice surface 32 Front surface of conventional scraper

Claims (4)

As shown in FIGS. 1, 2, 3, and 4, the space surrounded by two metal concentric cylinders having different diameters is an evaporator 3, and the inner diameter side surface of the inner cylinder is an ice making surface 31. A rotor 2 equipped with a resin scraper 5 that scrapes off the ice generated on the inner cylinder is disposed on the inner diameter side of the inner cylinder, and salt water is poured into a space sandwiched between the inner cylinder of the rotor 2 and the evaporator 3 to produce sherbet ice. In the ice generator, the resin scraper 5 has a V shape opened toward the ice making surface 31, and the V-shaped root 23 can be freely rotated by the support bracket 17 and the support rod 18 provided on the rotor. An ice generator characterized in that it has a V-shaped one end longer than the other end to scrape off the ice, and the other end 22 has a slight clearance from the ice making surface in operation. Scrapes Par. 4. A scraper for an ice generator having a structure similar to that of claim 1, wherein the tip of the resin scraper 5 that scrapes ice is formed in a sawtooth shape as shown in 20 and 21 of FIG. 2 and 3, a flow path 16 is provided between the surface connecting the bottom side of the support bar of the scraper 5 (broken line in FIG. 3) and the outer diameter surface of the rotor 2 for scraping ice. An ice generator having a structure similar to that of claim 1. As shown in FIG. 2, a blade 15 serving as an auxiliary pump function or a spiral blade 35 or a blade 36 having an auxiliary pump function in the vicinity of the rotor is provided on the surface of the rotor 2 that supports and rotates the scraper 5 to flow in the axial direction. An ice generator having a structure similar to that of claim 1, wherein dynamic pressure is applied.

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