The present disclosure provides an ice-making machine comprising an evaporator, and a method for operating the machine. More particularly, the present disclosure provides an ice-making machine that uses both pan and partition evaporators, as well as pin evaporators. The method comprises independently controlling the evaporators, so that they can be running together, or individually one at a time.
The shape of ice particles (e.g., cubes) is largely consumer driven, and can depend greatly on the visual appeal to the customer. Currently available evaporators produce ice that has at least one aspect that is undesirable to a consumer. The current evaporators may produce ice that doesn't form evenly, leading for example to ice cubes that have an empty center or “dimple” in the middle of the cube. Other evaporators that try to form the ice cube more evenly produce ice particles or cubes that are not visually appealing to the consumer.
Accordingly, there is a need for an ice-making machine and evaporator that forms ice particles efficiently and in such a way that the resulting particle is visually appealing to a consumer.
The ice making machine of the present disclosure comprises an evaporator having both a pan- or box-shaped evaporator as well as a pin-shaped evaporator. The pan-shaped evaporator has bent up edges or side walls that define a center portion, and there are a plurality of partitions in the center portion that form at least one cell. The pins of the pin-shaped evaporator project into the cell(s). Water is sprayed on or otherwise applied to the cell, where it is frozen. This provides a generally cube-shaped ice particle that has the cube appearance that many consumers prefer. The pan-shaped evaporator cools the water and the forming cube from the exterior sides inward. The pin-shaped evaporator cools the water and the forming cube from the inside out, ensuring a quicker and more efficient cooling, while also preventing the dimples or divots on the ice particles that many currently available evaporators provide.
The two evaporators of the present disclosure can be independently operated. They may both be in operation at the same time, or one may be in operation while the other is shut off. The method of the present disclosure comprises controlling the evaporators in this way.
Accordingly, in one embodiment the present disclosure provides an ice-making machine comprising a compressor, a refrigerant, a first evaporator, and a second evaporator connected to the first evaporator. A first fluid line is connected to the compressor at one end and the first evaporator at a second end, for carrying a first portion of the refrigerant to the first evaporator. A second fluid line is connected to the compressor at one end and the second evaporator at a second end, for carrying a second portion of the refrigerant to the second evaporator. A solenoid valve is connected to the first fluid line, for selectively opening and closing the first fluid line to the flow of refrigerant therethrough.
The present disclosure also provides a method of making ice with the ice-making machine, comprising the steps of:
Referring to the Figures, and in particular
In this way, evaporator 1 can provide several advantages not found in prior art ice-making machines. The ice particles 40 produced by evaporator 1 can have a generally cubic shape, which is commonly preferred by customers. Unlike currently available cubic-shaped ice, however, the particles 40 produced by evaporator 1 are frozen through to or at a center portion, except in the area where pin evaporator 20 projects into cell 30. There are no significant dimples or crevices in ice particle 40.
Referring specifically to
A plurality of grid elements 16 are connected to one another, and placed into center 15, forming a plurality of cells 30. A plurality of refrigerant coils 18 are connected to plate 12 on an opposite of plate 12 from cells 30 (
Referring to
Referring to
As seen in
One benefit of the machine of this disclosure is to provide a shorter path for pulling the heat out of the water to form ice in evaporator 1. In currently available devices, as an ice layer builds up on the surface of a pan-style evaporator, the evaporating temperature of the refrigerant inside the serpentine tubing on the back of the pan evaporator must get colder to continue pulling heat from the water through the layer of ice that has already formed. That is, once ice starts to form a layer on the surface of an evaporator, the refrigerant passing by on the other side of that surface must get colder and colder, since it is pulling heat from the unfrozen water through a layer of ice. The efficiency of the compressor in such a system goes down as the evaporating temperature of the refrigerant gets colder. With evaporator 1 of the present disclosure, by cooling each cube from the outside (via the walls of cells 30, and pan evaporator 10) and the inside (via pins 24 in pin evaporator 20), the present disclosure reduces the average thickness of ice that a refrigerant has to work through, and allows for the refrigeration system to run at a warmer (and thus more efficient) evaporating temperature.
As noted in
After exiting the expansion valves 107 and/or 108, the refrigerant is cooled significantly, to the point where it can freeze water in contact with either of evaporators 10 or 20. The refrigerant that leaves evaporator 1 is returned to compressor 101 to restart the compression cycle. During a heating or ice-release cycle, solenoid 105 (and optionally 106) can be closed, and one or both of harvest valves 111 and 112 can be opened so that warm refrigerant passes through pan evaporator 10 and/or pin evaporator 20, respectively. An optional harvest strainer 110 can prevent any particulate matters from passing through harvest valves 111 and 112.
The ability to route refrigerant through pan evaporator 10 and pin evaporator 20 separately and independently of one another provides several advantages in machine 100. It provides significant control over the cooling rate and shape of the cubes formed with in the evaporators. For example, at the beginning of a cooling cycle, refrigerant can pass through each of evaporators 10 and 20. Near the end of the cooling cycle, as the cube is taking its final shape, solenoid valve 105 can be closed, so that refrigerant only runs to pin evaporator 20. This allows for pin evaporator 20 to finish forming the cube by filling in the center of the cube, without any additional cooling from the outer sides of the cube.
One method of making ice that can be performed with machine 100 is described as follows. During a first part of a freeze cycle, liquid line solenoid 105 is open, to allow the refrigerant to flow into pan evaporator 10. During this part of the freeze cycle, refrigerant will also flow to pin evaporator 20, whether optional solenoid 106 is present or not. This provides maximum cooling for machine 100 and will form ice on the walls of cells 30 and on pins 24. During a second part of the freeze cycle, liquid line solenoid 105 is closed, preventing refrigerant from flowing into pan evaporator 10, while refrigerant continues to run to pin evaporator 20. (If used, liquid line solenoid 106 is open at this point.) This will concentrate the cooling on pins 24, to help fill out the center of the cubes. During a harvest cycle one or both of harvest solenoids 111 and 112 are open, allowing warm refrigerant vapor to heat up evaporator 1 and detach ice from evaporator 1.
It does not matter if liquid line solenoid 105 (and optionally 106) is open or closed during the harvest portion of the ice making cycle. Harvest valves 111 and 112 will have a pressure drop across them during the harvest cycle, so the pressure will still be higher on the inlet side of expansion valves 107 and 108 than the outlet sides. If any refrigerant were to flow through valves 107 and 108 it would still flow from inlet to outlet, not backwards. This is why it does not matter if solenoids 105 and 106 are open or closed during the harvest cycle.
Referring to
The perforations in shield 201b are such that formed ice particles 40 cannot pass through. Rather, shield 201b is at an incline to horizontal, so that the harvested ice particles 40 hit shield 201b and slide sideways toward curtain 207 and into a bin (not shown) on the other side of curtain 207. As described in greater detail below, when the ice level in the bin reaches a certain height, curtain 207 will not be able to drop back into its vertical position. This indicates that the bin is full, and ice making should be suspended until the bin is emptied.
Pump mechanism 200 is advantageously designed so that it provides water to evaporator 1 in such a way that water is not exposed to any plastic in machine 100 that is cold enough to freeze the water. When part of the ice slab formed during a freeze process is frozen to a low thermal conductivity material like plastic during a long cycle, it is difficult during a short harvest cycle to push heat into that plastic fast enough to get the ice to release from the plastic. In the present disclosure, water is sprayed onto evaporator 1, and allowed to drain back into sump 202, without letting the water touch any cold plastic. This shortens the time period required to get the ice to release from evaporator 1 and fall away.
High water level float switch 203 and low water level float switch 204 are shown, located in sump 202. Switches 203 and 204 determine when the water level in sump 202 reaches a set high point and a set low point, respectively. A thermistor 208 can measure the temperature of evaporator 1. Thermistor 208 can be attached to pan evaporator 10 directly, for example to plate 12, or to one or more of coils 18. If thermistor 208 is attached to coils 18, it can be at a point either before or after coils 18 contact plate 12.
Referring to
After a set period of time (shown as five minutes), or when high water level float switch 203 detects that the water lever in sump 202 has reached a desired height, machine 100 enters state 2, a first freezing stage. At this point, there is enough water in sump 202 to create a desired amount of ice. Pump 201 is activated, so that water is sprayed onto the surface of evaporator 1. The refrigerant was flowing to evaporator 1 in state 1, so that the evaporator is ready to freeze water in stage 2. The refrigerant continues to flow during state 2. Since there is enough water for the time being, water inlet valve 105 is closed.
After either a second period of time (here shown as forty minutes), or when thermistor 208 determines that the surface of evaporator 1 has reached a first set temperature or lower, machine 100 enters state 3, a second freezing stage. In one embodiment, the first set temperature is zero degrees Fahrenheit or lower. At this point, most of the ice has been formed, so solenoid 105 is closed, cutting off refrigerant flow to pan evaporator 10. Pump 201 continues to run. Solenoid 106, if used, is left open. In either embodiment, the flow of refrigerant to pin evaporator 20 continues to flow during this stage.
After a third period of time (shown as twenty minutes), or when low water level float switch 204 detects that the water lever in sump 202 has reached a desired low, machine 100 enters state 4, a harvest state. During state 3, the pump continues to apply water to evaporator 1 for freezing. Since there is no new supply of water through water inlet valve 205, there will eventually not be enough water in sump 202 to apply to evaporator 1. This is determined either by switch 204 or by the passing of the third period of time.
State 4 is a harvest phase, and at this point, pump 201 is shut off, so that no more water is applied to evaporator 1. Rather, compressor 101 continues to operate, passing hot refrigerant through harvest solenoids 111 and 112, which are now open. Warm refrigerant passing through pan evaporator 10 and pin evaporator 20 releases the cubes 40 from cells 30, where they fall into the bin. As previously discussed, it does not matter whether solenoid 105 and optional solenoid 106 are open or closed at this point. After a fourth period of time (here shown as five minutes), machine 100 can return to state 0.
Alternatively, during stage 4 the system may determine that curtain 207 has been open for more than a fifth period of time (here shown as thirty seconds). As previously described, this is an indication that the bin is full of harvested ice, and curtain 207 is not able to close. This condition will also cause the system to return to state 0. If curtain 207 continues to open and close without being open longer than the fifth period of time, this is an indication that the bin is not yet full. In this situation, the system will return to state 1 to start the ice-making cycle again.
While the present disclosure has been described with reference to one or more particular embodiments, it will be understood by those skilled in the art that various changes may be made, and equivalents may be substituted for elements thereof without departing from the scope thereof. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure without departing from the scope thereof. Therefore, it is intended that the disclosure is not limited to the particular embodiment(s) disclosed as the best mode contemplated for carrying out this disclosure.
The present application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/975,444, filed on Feb. 12, 2020, which is herein incorporated by reference.
Number | Name | Date | Kind |
---|---|---|---|
2949019 | Roberts | Aug 1960 | A |
3380261 | Hendrix et al. | Apr 1968 | A |
4774815 | Schlosser | Oct 1988 | A |
5182925 | Alvarez et al. | Feb 1993 | A |
20020043073 | Park et al. | Apr 2002 | A1 |
20090120122 | Gradl | May 2009 | A1 |
20170003062 | Olson, Jr. | Jan 2017 | A1 |
20180017304 | Knatt | Jan 2018 | A1 |
20200400363 | Junge | Dec 2020 | A1 |
Entry |
---|
International Search Report dated Apr. 28, 2021 for PCT Appl. No. PCT/US2021/017521. |
Written Opinion dated Apr. 28, 2021 for PCT Appl. No. PCT/US2021/017521. |
International Preliminary Report on Patentability (IPRP) dated Dec. 24, 2021 for PCT Appl. No. PCT/US2021/017521. |
Number | Date | Country | |
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20210247121 A1 | Aug 2021 | US |
Number | Date | Country | |
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62975444 | Feb 2020 | US |