Description

REFRIGERATOR FOR GRAIN WITH EVAPORATOR INSTALLED IN RECEIVING PART

Technical Field

[1] The present invention relates to a refrigerator including an evaporator in the center of a receiving space, and more particularly, to a refrigerator in which an evaporator is installed in the central of a receiving space and a receiving tube is installed to receive the evaporator, such that cool air inside the refrigerator is uniformly dispersed. Background Art

[2] Generally, an evaporator of a refrigerator is installed in a wall. In case where objects to be refrigerated are grains, cool air circulation is interrupted so that cool air is not appropriately supplied to whole grains. Hence, it is advantageous that the evaporator is installed in the central of a receiving space of the refrigerator. This is disclosed in Korean Patent Application No. 2003-19092, filed by the present applicant. The Patent Application No. 2003-19092 also discloses that dew condensation can be effectively prevented by contacting grains with the container receiving the evaporator rather than by directly contacting grains with the evaporator.

[3] Korean Patent Application No. 2003-100422 filed by the present applicant is an improvement of Korean Patent Application No. 2003-19092. Korean Patent Application No. 2003-100422 discloses a refrigerator that can more effectively prevent the container form being dew-condensed or frozen. Disclosure of Invention Technical Problem

[4] A technical feature disclosed in Korean Patent Application No. 2003-100422 is that dew condensation and freezing can be suppressed by material characteristics of a container and arrangement of an evaporator. However, the evaporator must be installed precisely and in a balanced manner. Furthermore, the refrigerator is influenced by external temperature and moisture. Technical Solution

[5] An object of the invention is to provide a refrigerator having an evaporator inside a container, which can prevent dew condensation and freezing, regardless of a left/right deviation of an evaporator installed in a container, and can eliminate moisture from the container, whereby the refrigerator is not influenced by external environment.

[6] Another object of the invention is to provide a refrigerator that can save energy by cooling a compressor installed under a container by using water generated within the container and can reduce a manufacturing cost because a cooling device (e.g., a

cooling fan) is not used.

Advantageous Effects

[7] According to the present invention, dew condensation and freezing can be prevented by eliminating moisture from a container receiving an evaporator, whereby the refrigerator can be always maintained in a clean state.

[8] Further, energy can be saved by cooling a compressor installed under the container by using water generated within the container, and a manufacturing cost can be reduced because a cooling device (e.g., a cooling fan) is not used.

[9] Furthermore, freezing and dew condensation can be solved by a heater. Therefore, a coil-type tube can be easily installed inside the container. Brief Description of the Drawings

[10] FIG. 1 is a partial cut-away perspective view of a refrigerator according to an embodiment of the present invention.

[11] FIG. 2 is an exploded perspective view of the refrigerator according to an embodiment of the present invention.

[12] FIG. 3 is an assembled cross-sectional view of the refrigerator according to an embodiment of the present invention.

[13] FIG. 4 is a block diagram illustrating a process of operating the refrigerator according to an embodiment of the present invention. Best Mode for Carrying Out the Invention

[14] According to an aspect of the present invention, a refrigerator includes: a container installed in a space where objects to be refrigerated are stored; a vertical rod vertically installed inside the container; an evaporator wound around the vertical rod in a coil type and installed inside the container; a heater installed in the container; and a control unit configured to heat the heater in a predetermined condition.

[ 15] The container may have a cylindrical side.

[16] The container may include a disk-shaped bottom plate with a through hole formed in the center thereof, and a flange protruding upwards from the bottom plate between the through hole and an outer periphery along a circumferential direction. The bottom surface of the cylindrical side of the container may be disposed between the flange and the outer periphery of the bottom plate, whereby the vertical rod passes through the through hole of the bottom plate and is connected to the bottom plate by a coupling member.

[17] The heater may be installed inside the container.

[18] The refrigerator may further include a coolant guide tube installed under the container to discharge water generated inside the container to the outside.

[19] The refrigerator may further include an elastic tube inserted over the vertical rod,

and the evaporator is wound around the elastic tube.

[20] The refrigerator may further include a temperature sensor for detecting an internal temperature of the container, and the operation of the control unit may be determined according to a temperature detected by the temperature sensor and the predetermined condition.

[21] The control unit may heat the heater when the temperature detected by the temperature sensor is identical to a temperature previously stored in the control unit.

[22] Hereinafter, a refrigerator according to the present invention will be described with reference to the accompanying drawings.

[23] FIG. 1 is a partial cut-away perspective view of a refrigerator according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of the refrigerator according to an embodiment of the present invention, and FIG. 3 is an assembled cross-sectional view of the refrigerator according to an embodiment of the present invention.

[24] Referring to FIGs. 1 through 3, a partition plate 2 having an opening in the center thereof is horizontally fixed to a housing 1. A grain storage 5 is defined above the partition plate 2 to store objects to be refrigerated, especially grains. A discharge container 4 is installed on a partition wall 6, which is defined under the partition plate 2, to contain grains discharged through the opening of the partition plate 2. The discharge container 4 is movably installed on the partition wall 6. A compressor 7 is installed in a space between the partition wall 6 and a partition wall 9. An opening/ closing member (not shown) is installed in the opening of the partition plate 2. The opening/closing member (not shown) is connected to a discharge lever 3 to open/close the opening of the partition plate 2. In FIG. 1 , when a user moves the discharge lever 3 right, the opening of the partition plate 2 is opened and the grains stored in the grain storage 5 fall down into the discharge container 4 through the opening. An evaporator is installed above the partition wall 2, and a container 100 is installed to receive the evaporator.

[25] The partition plate 2 is concaved toward the opening 21, so that the grains stored in the grain storage 5 can be discharged through the opening 21. Support bars 22, 23 and 24 are horizontally installed and welded at four corners of the partition plate 2. The support bar 22 has two ends connected to diagonal corners. The support bar 23 has one end connected to another corner and the other end connected perpendicular to the support bar 22. The support bar 24 has one end connected to the rest corner and the other end connected perpendicular to the support bar 22. A vertical rod 101 is vertically installed and welded onto the center of the support bar 22. Screw threads with predetermined length are formed at lower and upper portions of the vertical rod 101. A bottom plate 110 of the container 100 has a through hole in the center thereof

and is inserted over the vertical rod 101 through the through hole. The bottom plate

110 of the container 100 includes a flange 111 formed in a circumferential direction between the through hole and the periphery. After the bottom plate 110 of the container 100 is inserted over the vertical rod 101, a washer 104 and a nut 102 are inserted over the vertical rod 101 to firmly couple the bottom plate 110 to the vertical rod 101. A bottom surface of the bottom plate 110 is mounted on a connecting portion of the support bars 22 and 23 and a connecting portion of the support bars 22 and 24, such that the bottom plate 110 is firmly fixed.

[26] A guide tube 105 is inserted over the vertical rod 101 and installed inside the flange

111 of the bottom plate 110. An elastic sponge tube 106 is installed on the guide tube 105. The guide tube 105 fixes and supports the sponge tube 106 when the evaporator 130 is inserted around the outer surface of the sponge tube 106. A cylindrical outer tube 120 of the container 100 is installed around the outer surface of the flange 111 of the bottom plate 110. The bottom plate 110, the guide tube 105, the outer tube 120, a top tube 140, and a guide tube 144, which will be described later, are formed of solid materials, preferably far-infrared radiating materials, so as to prevent their deformation. In particular, ceramic or loess is more preferable because it can absorb a certain amount of moisture, which may be generated in a cooling operation, while radiating far-infrared rays. The evaporator 130 is installed around the outer surface of the sponge tube 106. The evaporator 130 has a straight-line portion 131 and a coil portion 132. The straight- line portion 131 extends straight downwards, and the coil portion 132 is wounded around the straight-line portion 131 upwards. An upper end of the straight-line portion 131 is connected to a capillary tube 133 through which a refrigerant is introduced into the straight-line portion 131.

[27] A heater 160 is installed between an insulation tube 150 and the outer tube 120 at the outside of the coil portion 132. The heater 160 may be formed of a plane heater or a nichrome wire. The heater 160 is heated by electricity supplied from the outside. In addition, a temperature sensor 170 is installed between the outer tube 120 and the insulation tube 150 to output a detected temperature to a control unit.

[28] A coolant guide tube 180 is installed in the bottom plate 110 of the container 100 such that water collected inside the container 100 can flow into the compressor 7.

[29] The top tube 140 is in contact with the top surface of the outer tube 120. The top tube 140 includes a cylindrical tube with a lower portion open. A bottom surface of the cylindrical tube is in contact with the top surface of the outer tube 120, and a through hole of a predetermined size is formed in the side of the top tub 140. Further, the top tub 140 has a rounded top surface in which a through hole is formed such that the vertical rod 101 can pass therethrough. The vertical rod 101 is inserted into the through hole of the top tube 140, and an exhaust tube 134 and the capillary tube 133 connected

to the upper end of the coil portion 132 of the evaporator 130 are taken out of the top tube 140 through an outlet 141 formed at a side of the top tube 140. After the exhaust tube 134 and the capillary tube 133 are taken out, the vertical rod 101 is coupled to and fixed by a washer 142 and a nut 143. The exhaust tube 134 is connected to a connection pipe and taken out of the housing 1 through the guide tube 144. The guide tube 144 is inserted into the outlet 141 of the top tube 140. The upper end of the vertical rod 101 protrudes upwards through the through hole of the top tube 140 and the nut 143 is exposed to the outside. The upper surface of the top tube 140 is coved by a cap 145 such that the exposed nut 143 can be hidden. The cap 145 may be adhered to the top tube 140 by an adhesive.

[30] FIG. 4 is a block diagram illustrating a process of operating the refrigerator according to an embodiment of the present invention.

[31] Referring to FIG. 4, a control unit 40 is a microprocessor with a data storage. A set temperature and a set time are stored in the data storage. An analog-to-digital conversion (ADC) unit 42, a heater driving unit 43, a control valve driving unit 45, and an input unit 47 are connected to the control unit 40. The ADC unit 42 is configured to convert an analog signal received from the temperature sensor 170 into a digital signal. The heater driving unit 43 is configured to drive the heater 171. The control valve driver 45 is configured to drive a control valve 46 for controlling an amount of fluid flowing into the evaporator 130. The input unit 47 is configured to input the set temperature and the set time to the control unit 40.

[32] An internal temperature of the container 100 is detected by the temperature sensor

170 during operation of the grain refrigerator and is converted into a digital signal by the ADC unit 42. The digital signal is inputted to the control unit 40. When the temperature value inputted from the ADC unit 42 is identical to a lower limit temperature stored in the data storage, the control unit 40 operates the control valve driving unit 45 to drive the control valve 46 to block a fluid passage, such that fluid does not flow into the evaporator 130. In this case, the control unit 40 also controls the heater driving unit 43 to heat the heater 171.

[33] When the temperature value inputted from the temperature sensor 170 during the heating of the heater 171 reaches an upper limit temperature, the control unit 40 operates the control valve driving unit 45 to drive the control valve 46 to make the fluid flow into the evaporator 130, and controls the heater driving unit 43 to stop heating the heater 171.

[34] Although the temperature sensor 170 is used in the above-described embodiments to expect the freezing or dew condensation, a variety of sensors (e.g., a humidity sensor) can also be used herein.

[35] In addition, when the temperature detected by the temperature sensor 170 is the

lower limit temperature, the control unit can control the heater driving unit 43 to heat the heater 171 for the set time. Further, the control unit 40 can control the heater driving unit 43 to heat the heater 171 periodically, instead of measuring the temperature. Furthermore, a variety of methods for eliminating moisture from the container 100 can also be carried out. [36] The grain refrigerator can be used as a heating cabinet as well as a refrigerator according to the setting of the upper limit temperature and the lower limit temperature. In using the grain refrigerator as the heating cabinet, only the heater 171 is operated while the evaporator 130 is not operated.