ES2361307T3 - REDUCED VOLUME ICE MAKING MACHINE. - Google Patents

Abstract

Ice machine comprising: (a) an evaporator (48) having a plurality of individual ice-forming cells (46), each cell (46) having a closed perimeter and an opening at a lower end; and (b) a water disperser (74) comprising a first tube section (100) and an inclined section (106) at an upper end of each of the plurality of individual ice-forming cells (46), and a baffle plate (108), characterized by a second tube section (104) downstream of the first tube section (100) and connected to the first tube section (100) by the inclined section (106), in which a The diameter of the second tube section (104) is greater than a diameter of the first tube section (100), and wherein the second tube section (104) is coupled to the upper end of the ice-forming cell (46 ), and wherein the baffle plate (108) is located within the water disperser (74) and aligned with a transition point (112) between the first tube section (100) and the inclined section (106) and attached to an internal wall of the first tube section (100) by L-shaped arms (114) that attach the baffle plate (108) to the inner wall of the first tube section (100), the baffle plate (108) having an upper surface and a lower surface (110), and wherein the lower surface (110) of the baffle plate (108) is aligned with the transition point (112) between the first tube section (100) and the inclined section (106), so that the flow of water that comes into contact with the baffle plate passes between the baffle plate and the shaped arms of L and is uniformly dispersed on an inner wall of the second tube section.

Description

The present invention relates generally to ice-making machines, and more particularly to low-volume ice-making machines suitable for residential or commercial use.

Ice making machines are widely used to supply cubed ice in commercial operations. Typically, ice making machines produce a large quantity of ice by flowing water over a large frozen surface. The frozen surface is thermally coupled to evaporator coils which are, in turn, coupled to a refrigeration system. The frozen plate, or evaporator, contains a large number of indentations on its surface where water flowing over the surface can collect. Typically, the notches are holes punched out in a metal plate that has high thermal conductivity. As the water flows over the indentations, it freezes to form ice.

To collect ice, the evaporator is heated by hot steam flowing through the evaporator coils. The evaporator plate is heated to a temperature sufficient to collect ice from the evaporator. Once released from the evaporator surface, a large number of ice cubes are produced, which fall into an ice storage bucket. The ice cubes produced by a typical ice making machine are square or rectangular in shape and have a somewhat thin profile. Rather than being a three-dimensional cube shape, ice cubes are tile-shaped and have small dimensions in height and width.

Unlike ice cubes produced by an ice machine, ice cubes produced in residential refrigerators are typically cube-shaped and larger than ice cubes produced by a commercial ice machine. Larger ice cubes are desirable for chilling beverages in commonly used home beverage glasses. Ice cubes that can be conveniently clamped are particularly desirable. Furthermore, ice made by conventional ice making machines freezes tap water to produce clear ice cubes, which are desirable. Most household ice machines found in refrigerators freeze standing water, resulting in cloudy ice that is less desirable.

In addition to producing small ice cubes, conventional ice making machines are typically large and bulky machines that require a large amount of space. An ice maker for home use, on the other hand, needs to have a small base area and a compact size that can fit under kitchen furniture countertops typically found in home kitchens. Home use ice machines must operate using electricity available at residential current and voltage.

Various ice machines have been developed and marketed for the residential market. Typically, these ice machines do not produce large clear ice cubes. One model produces large transparent cubes, but uses an evaporator which is quite difficult to produce. Furthermore, the evaporator is not totally reliable and uses jets of water under pressure that have a tendency to plug, especially when routine maintenance is not performed. Non-existent or, at best, infrequent maintenance is typical for residential ice machines. Accordingly, there is a need for a compact ice machine capable of producing large clear ice cubes, with the machine being reliable and compatible for both residential and commercial use, and which can be constructed at a reasonable cost using automated technology.

DE-C-936042 describes an ice machine with an evaporator, a plurality of individual ice-forming cells, a water dispenser and a baffle plate to direct water entering the upper end of the ice-forming cell to an inner surface of the cell.

The present invention provides an ice machine as set forth in claim 1.

The invention includes an ice machine having an evaporator with a plurality of individual ice-forming cells. Each ice-forming cell has a closed perimeter and an opening at a lower end. A water distributor is coupled to the evaporator and is configured to supply water at or near an upper end of each of the plurality of individual ice-forming cells so that the water flows downward within the perimeter of the ice-forming cells. individual ice. A water recirculation system including a sump, a water pump located within the sump, and a water recirculation pipe is coupled to the water pump and the water distributor. A cooling system is configured to cool each of the plurality of ice-forming cells from outside the perimeter, so that individual ice cubes are formed in the ice-forming cells.

An ice machine monitoring system may be provided that includes an electronic control unit and an evaporator configured to produce ice cubes and to discharge excess water. A water holding unit has a first chamber and a second chamber, where the first chamber is configured to receive excess water from the evaporator and to supply water to the second chamber. A water detection probe is located in the second chamber and is configured to detect the presence of water flowing into the second chamber from the first chamber and to transmit a signal to the electronic control unit.

two

The ice machine includes an evaporator having a plurality of individual ice-forming cells, each cell having a closed perimeter and an opening at a lower end. A water disperser is located at an upper end of each of the plurality of individual ice-forming cells. The water disperser includes a baffle plate located within the water disperser and attached to an internal wall thereof. The baffle plate directs a flow of water entering the upper end of the ice-forming cell outward onto an inner surface of the ice-forming cell.

A transparent ice cube produced by an ice making machine includes upper and lower ends and an opening in a central part extending from the upper end to the lower end. The opening has a relatively larger cross-section at the upper and lower ends and a relatively smaller cross-section at a mid-section of the ice cube.

The ice machine can include a multi-level evaporator that has at least two levels. Each level includes a plurality of individual ice-forming cells, each ice-forming cell having a closed perimeter and an opening at a lower end. The ice-forming cells are vertically aligned to form vertical cell stacks. A thermal insulator is located between the ice-forming cells in the vertical cell stacks. A water distributor is coupled to the evaporator and configured to supply water at or near an upper end of each of the plurality of individual ice-forming cells at a higher level. A water recirculation system includes a sump, a water pump located within the sump, and a water recirculation line coupled to the water pump and the water distributor. The water distributor is configured to supply water to the multi-level evaporator so that the water flows down from the uppermost level in each cell stack and out of the multi-level evaporator through a lower level and into the sink.

As also described below, one method of operating an ice machine includes circulating water through a plurality of hollow ice-forming cells while cooling the ice-forming cells with a coolant, and monitoring the flow of water through. through the ice-forming cells, and initiating a collection cycle to eject ice cubes from the ice-forming cells when a decrease in water flow rate through the ice-forming cells is detected.

As also described below, a method of handling an ice machine includes forming ice cubes into individual ice forming cells, and initiating a collection cycle to release the ice cubes from individual ice forming cells, and detecting the falling of ice cubes from the ice-forming cells, and monitoring a time interval between each ice cube detection event, and if no detection event occurs during a predetermined time interval, control returns to the formation of ice cubes and subsequently start a collection cycle.

The ice machine may include water distributing means coupled to the evaporating means for supplying water at or near an upper end of each of the plurality of individual ice-forming cells. The ice machine also includes water recirculation means for recirculating water passing through the ice-forming cells back to the water distribution means, and cooling means for cooling each of the plurality of ice-forming cells. ice from outside the perimeter so that individual ice cubes are formed in the ice-forming cells.

As also described below, one method of operating an ice machine includes using a water pump to pump water from a water sump through a water manifold and to an evaporator coupled to the water manifold, the evaporator having a plurality of individual ice-forming cells, each cell an opening at a lower end; and cooling each of the plurality of ice-forming cells so that individual ice cubes are formed in the ice-forming cells; stopping the water pump and collecting the ice cubes from the ice-forming cells, while monitoring the fall of ice cubes from the ice-forming cells and recording a sequential number of collection cycles. With each pre-programmed number of collection cycles, the water pump begins pumping water to the water manifold and evaporator, and a water inlet valve opens to circulate water to the water sump. The method further comprises continuing to drive the water pump and flowing water into the water sump until a level of water in the water sump contacts a sensor located in the water sump; stop the water pump so that the water flows to the water sump from the water distributor and evaporator and raise the water level enough to activate a drain siphon in the water sump; drain water from the water sump until the drain siphon stops; continue to flow water to the water sump through the water inlet until the water level rises and comes into contact with the sensor; turn the water pump back on to pump water to the water distributor and evaporator; continue to operate the water pump and flow water into the water sump until a water level in the water sump contacts a sensor located in the water sump again; and close the water inlet valve.

3

A preferred embodiment of the present invention will now be described, by way of example only, and with reference to the accompanying figures, in which:

Figure 1A is a perspective view of a cabinet for housing an ice-forming machine according to the invention

Figure 1B is an elevation view showing the rear panel of the cabinet illustrated in Figure 1A;

Figure 2 is a partial front view of an ice making machine configured in accordance with the invention;

Figure 3 is a perspective view of a double evaporator of the ice making machine illustrated in Figure 2;

Figure 4 is a bottom view of one of the evaporator plates in the ice making machine illustrated in Figure 2;

Figure 5 is a cross-sectional view of the evaporator and manifold illustrated in Figure 2 taken along section lines V-V of Figure 2;

Figure 6 is a top view of a water disperser illustrated in Figure 5;

Figure 7 is a perspective view of an ice cube produced by the ice making machine illustrated in Figure 2;

Figure 8 is a partial cross-sectional view of the evaporator, ice detection unit, water collection unit, and sump of the ice-making machine illustrated in Figure 2, taken along section lines VIII-VIII;

Figure 9 is a schematic diagram of the water system of the ice machine illustrated in Figure 2;

Figure 10 is a perspective view of the water collection unit of the ice making machine illustrated in Figure 2;

Figure 11 is a side view of the water collection unit illustrated in Figure 10;

Figure 12 is a schematic diagram of the refrigeration cycle of the ice-making machine illustrated in Figure 2,

Figure 13 is a table summarizing the operational characteristics of the ice machine of the present invention; Y

Figure 14 is a table summarizing the operational sequence of the ice machine of the present invention during a cleaning cycle.

It will be understood that, for clarity of illustration, not all elements shown in the figures have been drawn to scale, for example some elements are oversized relative to other elements.

In accordance with a preferred embodiment of the invention, an ice machine is provided that produces large individual clear ice cubes and is contained in a compact size cabinet suitable for use in a residential or commercial setting. An embodiment of a cabinet suitable to house the ice machine of the invention is illustrated in Figures 1A and 1B. A cabinet 20 is configured to remain upright on a horizontal surface and has a somewhat narrow profile to facilitate placement of cabinet 20 in small spaces found in a residential kitchen or small commercial kitchen. In one embodiment of the invention, cabinet 20 has a height of no more than about thirty inches, a depth of no more than about twenty-three inches, and a width of no more than about fifteen inches.

Ice cubes can be accessed from an ice storage bucket (not shown) through a door 22 on a front face 24. The front face 24 also includes a cooling vent 26 that allows air flow to the ice machine cooling system. Cabinet 20 is preferably constructed from a combination of durable materials including lightweight plastics and metal alloys. The electrical and water supply to the ice machine is provided through a rear panel shown in Figure 1B. The rear panel 28 has a water inlet connection 30, an electrical port 32, and a water drain connection 34. Although the service connections are illustrated in a particular location on the rear panel 28, the service connections may be located at various locations on the rear panel, or alternatively, on a side panel of cabinet 20.

4

A perspective view of various functional components of the ice machine is illustrated in Figure 2. The components shown in Figure 2 include a water recirculation means which, in one embodiment, includes a water sump 36, a water pump water 38, and a water recirculation pipe 40. The water recirculation pipe 40 is coupled to a water distributor 42. A water distributor means, which, in one embodiment, is constituted by the water distributor 42, includes collector lines 44 that feed water into individual ice-forming cells 46A and 46B of an evaporator 48. Evaporator 48 includes refrigerant lines 52 that transfer heat from individual ice-forming cells 46 to freeze flowing water into the cells from the manifold pipes 44.

The ice cubes produced in the ice-forming cells 46A and 46B fall into a transfer compartment 54. The transfer compartment 54 includes an inclined slotted surface 56 that directs the ice cubes toward a buffer element 58. The buffer element 58 it is mounted on hinges 60 and is equipped with a magnet 62 which operates in conjunction with an ice damping element switch (its silhouette is shown as element 63 in Figure 10). In one embodiment, the ice damping element switch 63 is a reed switch; alternatively, the ice damping element switch 63 may be a Hall effect sensor, or the like. Damper element 58 is configured to swing open on hinges 60 each time an ice cube strikes the internal surface of damper element 58.

Those skilled in the art will recognize that the arrangement of components illustrated in Figure 2 is only one of many possible arrangements. Accordingly, the position of the components relative to each other may be different from that shown in Figure 2. For example, the pump motor 38 may be located below the transfer compartment 54, or outside the transfer compartment. freezing and water. Also, the size of the transfer compartment 54 may vary, depending on the ice making capacity of the ice machine.

A sump drainage system 64 resides in a lower portion of the water sump 36. As will be described below, the sump drainage system 64 is configured to draw water from the water sump 36 during drainage operations of and of. filled with water. The water sump 36 is also equipped with a sump sensor 66 and a reference probe 68. As will be described below, the sump sensor 66 and the reference probe 68 operate to provide signals for the electronic control system during operation of the ice machine. Preferably, the sump sensor 66 and the reference probe 68 are capacitance probes, although other types of water detection probes can also be used.

Figure 3 is a perspective view of the evaporator 48. In the embodiment illustrated in figure 3, the evaporator means, which in one embodiment of the invention constitute the evaporator 48, are equipped with an upper thermally conductive plate 70 and a conductive plate thermally lower 72. The individual ice-forming cells 46A are located on the upper thermally conductive plate 70 and the ice-forming cells 46B are located on the lower thermally conductive plate 72. The lower thermally conductive plate 72 rests on an upper member 73 of the transfer compartment 54.

Each ice-forming cell 46A has a water disperser 74 located at an upper end of the cell. A thermally insulating coupler 76 connects ice-forming cells 46A to ice-forming cells 46B. An inlet 78 of the refrigerant pipe 52 enters the upper thermally conductive plate 70 and transversely traverses a lower surface of the upper thermally conductive plate 70 between adjacent rows of ice-forming cells 46A. A connector 80 connects an outlet portion 82 of the refrigerant pipe 52 to an inlet portion 84. The inlet portion 84 enters the lower thermally conductive plate 72 and longitudinally traverses a lower surface of the lower thermally conductive plate 72 between rows. adjacent ice-forming cells 46B. An outlet 86 returns refrigerant for recycling through the ice machine refrigeration system.

The serpentine configuration of the refrigerant pipe 52 is illustrated in the bottom view of the upper thermally conductive plate 70, illustrated in Figure 4. The refrigerant pipe 52 is attached to opposite elongated sides 92 and 94 and to the lower surface 90 of the Upper thermally conductive plate 70. Refrigerant pipe 52 is connected identically to lower thermally conductive plate 72. Refrigerant pipe 52 is arranged so that refrigerant flows through inlet portion 78 and transversely passes through a portion center of the upper thermally conductive plate 70 first, and then longitudinally the perimeter of the upper thermally conductive plate 70 before exiting through the outlet portion 82. In this way, the upper thermally conductive plate 70 is subjected to the lower temperature part of the refrigerant pipe 52 in the central part of the plate. The same coolant flow pattern is used for the lower thermally conductive plate 72. Those skilled in the art will understand that other flow patterns are possible. For example, the flow of coolant can be directed to the perimeter of the plate first, and then to the central part of the plate, or it can be divided and flow simultaneously in different parts of the plate.

As illustrated in FIG. 4, the ice-forming cells 46A are arranged in regular rows and columns on the upper thermally conductive plate 70. Each of the ice-forming cells 46A is welded into an opening in the thermally conductive plate. Ice-forming cells 46A extend through thermally conductive plate 70 such that a central axis passing through ice-forming cells 46A is oriented at approximately 90 ° with respect to the plane of thermally conductive plate 70. The serpentine path of the refrigerant pipe 52 is configured so that heat transfer takes place through the walls of the ice-forming cells 46A and to the thermally conductive plate 70.

5

Those skilled in the art will understand that the regular rows and columns of the ice-forming cells 46A illustrated in Figure 4 may vary, such that the number of rows and columns may be less or greater than that illustrated in Figure 4. Furthermore Although the ice-forming cells 46A are shown in a regular series of rows and columns, the relative position of the ice-forming cells with respect to one another can vary over a wide range of geometric patterns. For example, the ice-forming cells 46A can be arranged in concentric circles, rectangular or diamond patterns, and irregular arrays, and the like. Furthermore, although in the exemplary embodiment, the ice-forming cells 46A are located at right angles to the thermally conductive plate 70, in alternative embodiments of the invention, the ice-forming cells may be located at an angle other than 90 ° with relative to the thermally conductive plate 70. For example, the ice-forming cells 46A may be inclined at an acute or obtuse angle relative to the thermally conductive plate 70. Additionally, the ice-forming cells may have a non-cross-sectional profile. round, such as a square, triangular, hexagonal, or octagonal profile, or the like. In this way, the ice machine can be customized to supply a particular distinctive ice cube shape, which can convey a brand designation, or the like.

As illustrated in FIG. 4, the thermally conductive plate 70 is generally rectangular in shape. In addition to shortened opposite side walls 86 and 88, thermally conductive plate 70 has opposite elongated sides 92 and 94. In the embodiment illustrated in Figure 4, the regular series of ice-forming cells 46A includes three rows extending parallel to opposite elongated sides 92 and 94 and four columns extending parallel to opposite sides 86 and 88. In other embodiments of the invention, thermally conductive plate 70 may have a square geometry and house a series of ice-forming cells 46A that it has an equal number of rows and columns. Alternatively, when the ice-forming cells 46A are arranged in concentric circles, the thermally conductive plate 70 may have a circular geometry.

To facilitate heat transfer between ice-forming cells 46A and 46B and refrigerant tubing 52, thermally conductive plates 70 and 72, refrigerant tubing 52, and ice-forming cells 46A and 46B are constructed of metal. which has a high thermal conductivity. In a preferred embodiment, the metal parts of the evaporator 48 are constructed of copper. Alternatively, other thermally conductive metals and metal alloys can be used. Accordingly, the plastic parts of the evaporator 48 and the water trap 44 are preferably constructed of a plastic material capable of being formed by injection molding. In one embodiment of the invention, the plastic parts of the ice machine are composed of an acrylonitrile-butadiene-styrene (ABS) plastic material. Materials other than ABS plastic, however, have a lower water absorption rate and may be preferred in some circumstances.

A cross-sectional view through one of the ice-forming cells 46A and 46B of the evaporator 48 taken along section line VV of FIG. 2 is illustrated in FIG. 5. Water enters the ice-forming cells. ice 46A through a hole 96 in a bottom of the collector pipe 44. Preferably, the water in the collector pipe 44 is pressurized so that a jet of water flows rapidly out of the hole 96. A reinforcement The outlet outlet 98 of the manifold line 44 is sealed against a first tube section 100 of the water disperser 74 by an O-ring 102. A first tube section 100 is integrally formed with a second tube section 104 of the water disperser. 74. The second tube section 104 has a larger diameter than the first tube section 100. The first tube section 100 is connected to the second tube section 104 by an inclined section 106.

A baffle plate 108 is positioned within the water disperser 74 such that a bottom surface 110 of the baffle plate 108 is aligned with a transition point 112 between the first tube section 100 and the sloped section 106. The baffle plate 108 is connected to the inner wall of the first tube section 100 by L-shaped arms 114. The L-shaped arms 114 are attached to the inner surface of the first tube section 100, so that the baffle plate 108 is positioned water down from the location where the L-shaped arms 114 meet the inner surface of the first tube section 100. In addition, a terminal end 116 of the outlet tube 98 abuts against the L-shaped arms 114.

The particular configuration of the L-shaped arms 114 functions to provide space between the inner wall of the first tube section 100 and the baffle plate 108, and to avoid obstructing the flow of water from the baffle plate 108. The shaped configuration of L allows the baffle plate 108 to bond to the inner wall of the first tube section 100, while minimizing the obstruction to the flow of water on the upper surface of the baffle plate 108. By moving the baffle plate 108 downstream from the At the point of attachment, the water dispersed from the baffle plate 108 can travel directly to the inner surface first and to the second tube sections 100 and 104 and onto an inner surface 118 of the ice-forming cell 46A. Accordingly, the L-shaped arms 114 help to produce a uniform distribution of water over the surface of the inner wall 118 of the ice-forming cell 46A.

6

Refrigerant pipe 52 is positioned against upper thermally conductive plate 70 and ice-forming cell 46A; so that heat is sufficiently transferred from a surface of the inner wall 118 of the ice-forming cell 46A. The coupler 76 is made of a thermally insulating material, so that the refrigerant piping 52 does not transfer heat from the coupler 76. Consequently, during ice machine operation, no ice will form on the inner surface of the coupler 76. between ice-forming cell 46A and ice-forming cell 46B. Thermal insulator 120 is located around a lower end 122 of ice-forming cell 46B. Thermal insulator 120 prevents ice formation on the outer surface of lower end 122.

A top view of the water disperser 74 is illustrated in Figure 6. The baffle plate 108 is a circular disk suspended in the center of the first tube section 100. As the water flows from the hole 96 in the outlet stiffener 98 strikes the upper surface of baffle plate 108 and is directed uniformly to the inner wall of the first tube section 100. Referring again to Figure 5, water directed from baffle plate 108 flows along the inner surface of the inclined section 106 and the second tube section 104 and on the surface of the inner wall 118 of the ice-forming cell 46A. The heat transfer that occurs between the ice-forming cell 46A and the refrigerant line 52 causes ice to form on the inner surface 118 of the ice-forming cell 46A. Water that does not freeze on inner surface 118 flows downward along inner surface 118 past coupler 76 and onto inner surface 123 of ice-forming cell 46B. Water also flows over the ice previously formed on the inner surface 118. Consequently, the freezing action that takes place in the ice-forming cells 46A and 46B begins on the inner surface of the ice-forming cells and proceeds toward the axis center of the ice-forming cells. According to a preferred embodiment of the invention, ice cubes are formed in the ice machine by an "outside in" freezing process.

As shown in Figures 5 and 6, the water disperser 74 has a projecting portion 115. The projecting portion 115 lies on the upper edge of the ice-forming cell 46A. An insert portion 117 of the water disperser 74 is inserted into the ice-forming cell 46A. The protruding part 115 and the insert part 117 secure the water disperser 74 in position at the upper end of the ice-forming cell 46A.

In the embodiment illustrated herein, evaporator 48 includes two overlying sets of ice-forming cells with a total of twenty-four cells. This configuration is capable of producing approximately thirty-five to approximately forty pounds of ice per day. Although the configuration of evaporator 48 illustrated herein includes two overlying thermally conductive plates, each containing a plurality of ice-forming cells, other configurations are possible. For example, more than two thermally conductive plates can be stacked one on top of the other. In this way, the capacity of the ice machine can be increased without increasing the area of the base of the machine. Furthermore, a single thermally conductive plate can be used. Furthermore, the diameter of the ice-forming cells may be larger or smaller than that illustrated in this document.

An ice cube 200 produced by the ice-making machine has the general appearance illustrated in Figure 7. The "outside-in" freezing action that takes place in ice-forming cells 46A and 46B produces ice cubes that they have a cylindrical outer surface and an hourglass shaped opening 202 in the center of the ice cube. During ice formation, liquid water continues to flow through the central part of the ice-forming cells until such time as the central hole freezes and closes or the freeze cycle ends and a collection cycle begins. . As will be described below, a control unit continuously monitors the amount of water flowing through the evaporator and initiates a collection cycle when the flow of water through the evaporator becomes restricted enough to indicate that most of the water flows through the evaporator. the ice cubes have just frozen.

The dimensions of the ice cubes produced by the ice machine of the preferred embodiment of the invention generally have the same dimensions as the first and second ice-forming cells 46A and 46B. In one embodiment of the invention, the ice cubes produced are about 1.25 inches in length and have a diameter "D" of from about one inch to about 1.25 inches. Ice cubes produced by the preferred ice making machine of the invention range in weight from about 12 to about 20 grams.

A partial cross-sectional view of the assembly illustrated in Figure 2 taken along section line VIII-VIII is shown in Figure 8. As described above, ice cubes falling from evaporator 48 into the Transfer compartment 54 are directed by slotted surface 56 toward damping element 58. The ice damping element switch 63 (its silhouette is shown in Figure 10) opens in response to the movement of magnet 62 each time an ice cube is removed. Individual ice or a series of ice cubes hit the buffer element 58. Water that does not freeze to ice in the evaporator 48 falls through the grooves in the slotted surface 56 and into a water collection unit 124. The water collection unit 124 is located above the water sump 36 and supplies water flowing from the evaporator 48 to the water sump 36.

7

Figure 9 is a schematic diagram (not drawn to scale) of the flow of water through the ice machine of Figures 2-8. The water flowing from the evaporator 48 falls into a first chamber 126 of the water collection unit 124. A bottom surface 128 of the water collection unit 124 includes an inclined portion 130 and a flat portion 132. A second chamber 134 it is formed in the water collection unit 124 by an overflow 136 that rises from the flat 132 of the bottom surface 128. The second chamber 134 has an outer wall 138 opposite the overflow 136.

Water can exit the first chamber 126 through a drain hole 140 located in the flat 132 or on the top of the overflow 136 and into the second chamber 134. Consequently, the water flowing over the upper surface of the overflow 136 may exit the second chamber 134 by flowing through a drain hole 142 located in flat portion 132 or on top of outer wall 138.

Water can be expelled from the water sump 36 via a sump drainage system 64. A siphon cap 144 is located on a vertical pipe 146. The vertical pipe 146 is connected to a drain pipe 148. The fresh water is supplies the water sump 36 through the water inlet pipe 150 and the water valve 151.

Recirculation of water through the ice machine is controlled by a control unit 152. The control unit 152 receives input signals from sensors located in the water sump 36 and the water collection unit 124. As noted described above, a sump sensor 66 and a reference probe 68 reside in the water sump 36. The sump sensor 66 is positioned to monitor the water level within the water sump 36. A water detection probe 153 is located in the second chamber 134 of the water collection unit 124. The water detection probe 153 is preferably a capacitance probe.

A perspective view of the transfer compartment 54 and the water collection unit 124 with the slotted surface 56 and the damping element 58 removed is illustrated in Figure 10. The water detection probe 153 resides in a probe housing 154 The probe housing 154 is located above the second chamber 134 and is attached to a side wall 156 and a rear wall 158. An opening 159 is created between the bottom of the probe housing 154 and the overflow 136 Water can flow from the first chamber 126 through opening 159 over the overflow 136 and into the second chamber 134. As described above, the ice damper switch 63, shown in silhouette, is located above the transfer compartment 54 behind the front panel on the right side.

A side view of the water collection unit 124 is shown in Figure 11. The water detection probe 153 is supported by a platform 160. The detection end of the water detection probe 153 extends into the interior of the second chamber 134 a predetermined distance to detect the presence of water in the second chamber 134.

Referring to Figures 9, 10 and 11, in accordance with the preferred embodiment of the invention, the first and second chambers 126 and 134 are configured to transfer water from the evaporator 48 to the water sump 36 and to detect when they have formed. ice cubes in evaporator 48. During operation, water falls from evaporator 48 through slots in slotted surface 56, and is directed to drain hole 140 by inclined surface 130 in first chamber 126. Water it also flows over the top of the overflow 136 into the second chamber 134 and out of the second chamber 134 through a restricted opening, such as the drain hole 142, and onto the outer wall 138. When enough water flows from the evaporator 48, the water level in the first chamber 126 is high enough for the water to flow continuously over the overflow 136 and into the second chamber 134. Under unrestricted flow conditions ions, water also flows from the second chamber 134 onto the outer wall 138. Consequently, the water holding capacity of the second chamber 134 is determined by the dimensions of the second chamber 134, the height of the overflow 136, the height of the outer wall 138, and the diameter of the drain hole 142.

As ice cubes begin to form in evaporator 48, the flow of water from evaporator 48 becomes restricted by ice that forms in ice-forming cells 46A and 46B. As ice continues to form, progressively less water flows from evaporator 48. Depending on the volume of the first chamber 126, the diameter of the drain hole 140, and the height of the overflow 136, at some point the water stops flowing. over the top of the overflow 136. At this time, the water remaining in the second chamber 134 is drained rapidly through the drain hole 142, exposing the water detection probe 153.

Control unit 152 continuously monitors probe 153 and, when the water level in second chamber 134 drops below probe 153, control unit 152 initiates a collection cycle to collect ice cubes from the evaporator 48. In accordance with one embodiment of the invention, the water detection probe 153 is uncovered when the volume of water flowing through the evaporator 48 decreases by approximately 1/3 compared to the total unobstructed flow of water through. evaporator. Next, the operational control of the preferred ice machine will be described.

The refrigeration system for the ice machine shown in figure 2 is illustrated in the schematic diagram of figure 12. The refrigeration system is mainly composed of a compressor 162, a condenser 164, an expansion device 166, an evaporator 48 (also shown in Figure 2) and interconnecting pipes 52, 163 and 167 thereof. In addition, the refrigeration system also includes a refrigerant dryer 168, a hot gas solenoid valve 170 for recycling hot gases through evaporator 48 after ice has formed, thereby releasing ice from evaporator 48, and interconnection pipes 172 thereof.

8

In operation, the refrigeration system contains a suitable refrigerant, such as a hydrofluorocarbon known under the trademark HFC-R-134a. The flow of refrigerant through the supply lines is shown by arrows and the physical state of the refrigerant at various locations is indicated by the highlighted schematic identified in Figure 12. In the freeze cycle, the compressor 162 receives a vaporous refrigerant at lowers pressure and compresses it, thereby increasing the temperature and pressure of this refrigerant. Compressor 162 then supplies this high-temperature, high-pressure, vaporous refrigerant through discharge line 163 to condenser 164, where the refrigerant condenses, changing from vapor to liquid. In this process, the refrigerant releases heat to the surroundings of the condenser, which is expelled from the ice machine.

High pressure liquid refrigerant from condenser 164 flows through refrigerant supply line 167 to dryer 168 and through expansion device 166, which is preferably a thermal expansion valve, and which serves to depressurize the liquid refrigerant. . An optional receiver is also shown on supply line 167. On a small volume ice machine, a receiver may not be a necessary component of the refrigeration system. In a large-scale ice machine, however, the demand for heat transfer may be high enough to require the use of a receiver as illustrated in Figure 12.

After passing through the expansion device 166, the low pressure liquid refrigerant flows to the evaporator 48 through the refrigerant pipe 52 (also shown in Figure 2), where the liquid refrigerant changes state to a vapor and, In the process of evaporation, it absorbs latent heat from the surrounding environment. Vaporization of the refrigerant cools the ice-forming cells 46A and 46B in the evaporator 48. The refrigerant is converted from a liquid to a vaporous state at low pressure and is returned to the compressor 162 to begin the cycle again. During the freeze cycle, the thermally conductive plates 70 and 72, and the ice-forming cells 46A and 46B are cooled well below 0 ° C, the freezing point of water.

The refrigeration system described herein may also contain a control circuit that causes the refrigeration system to cool the ice-forming cells 46A and 46B well below freezing on initial start-up of the ice machine. to start the freeze cycle. This improvement is described in US Patent No. 4,550,572. As a result of this improvement, on initial start-up, evaporator 48 is cooled well below freezing before starting water pump 38 and supplying water to the ice-forming cells. If desired, the sub-freeze cooling process can also be performed during normal ice machine operation.

When the ice machine enters its take-up cycle, the hot gas solenoid 170 opens and the hot vaporous refrigerant is introduced through line 172 into evaporator 48. The take-up cycle continues until the cooler unit control 152 determines that all ice cubes have fallen from ice-forming cells 46A and 46B.

The operating characteristics of the preferred ice machine of the invention will now be described. The operational characteristics of the ice machine described below are summarized in the table shown in figure 13.

Start-up sequence and freeze cycle

During initial start-up, or during a new start-up of the unit, the damper switch is closed and the water inlet valve 151 is open. If the sump sensor 66 is not in contact with the water, the water valve 151 opens until the sump sensor 66 contacts the water. When the water level in the water sump 36 rises to a level sufficient to contact the sump sensor 66, the water valve 151 closes. After the water valve 151 closes, the hot gas solenoid 170 turns on for approximately 20 seconds and then the solenoid closes and the compressor 162 turns on. About 30 seconds after activating compressor 162, water pump 38 starts. The icemaker is now in a normal freeze cycle. During the first fifteen minutes of the freeze cycle, the water detection probe 153 may or may not be in contact with the water; therefore, the signals from the water detection probe 153 are ignored by the control unit 152 for the first ten to fifteen minutes of each freeze cycle. During the freeze cycle, the control unit 152 will continue to operate in the freeze cycle even if the ice damper switch 63 is open. Alternatively, the signal from probe 153 can be sampled to see if semi-molten ice has formed and pump 38 is cavitating. If this occurs, a brief opening of the water inlet solenoid 151 will introduce hotter fresh water, causing the semi-melted ice to melt.

9

If the master control switch is turned to the "OFF" position during the freeze cycle, the control unit 152 will turn off the ice machine immediately. If the master control switch is set to the "CLEAN" position during a freeze cycle, the control unit 152 will turn off the icemaker immediately, and initiate a cleaning cycle as described below.

Collection cycle

As ice cubes 200 are formed in evaporator 48, a hole 202 in the center of the cubes will begin to freeze shut and restrict the flow of water through ice-forming cells 46A and 46B of evaporator 48. When the water flow becomes sufficiently restricted, the water will overflow from the overflow 136 into the second chamber 134. At some point, the water level in the second chamber 134 drops to a level that leaves the sensing probe for exposed water 153, after which the control unit 152 triggers a harvest cycle. From the time point where the contact between the water and the water flow probe 153 is broken, the water pump 38 is turned off, and the hot gas valve 170 is opened.

As the ice cubes fall from the evaporator 48 and into the storage bucket, the ice damper switch 63 will open and close again several times. When a period of approximately twenty seconds passes without detecting an opening of the ice damper element switch 63, the control unit 152 assumes that all the ice has been collected from the evaporator 48. The hot gas solenoid 170 closes from twenty seconds after the last time the ice damper switch 63 opens. At that time, the water pump 38 starts and the water inlet valve 151 opens. The water inlet valve 151 remains open until the water level in the water sump 36 rises to a level sufficient to contact the sump sensor probe 66. The icemaker is now in another freeze cycle .

If the ice damper switch 63 remains open for approximately twenty seconds at a time, the control unit 152 interprets this condition as indicating that the ice bucket is full and the ice is holding the damper element open. Control unit 152 then places the ice maker in an automatic shutdown mode. In automatic shutdown, compressor 162 and water pump 38 are turned off and hot gas solenoid 166 and water inlet valve 151 are closed.

When the ice damping element switch 63 is closed again, if the ice machine has been off for three hundred seconds, the control unit 152 restarts the start-up sequence described above. Alternatively, if the icemaker has not been off for three hundred seconds and the damper switch 63 is closed again, the control unit 152 delays start-up again until the three hundred second time period has elapsed. This period of time can be canceled by moving the master control switch to the "OFF" position, and back to the "ON" position. After three hundred seconds in a harvest cycle, if the ice damper element switch 63 fails opened at least once, control unit 152 aborts the harvest cycle and returns the ice machine to a freeze cycle.

Collection cycle with water flush

A flush collection cycle is started every fourth collection cycle. As the water flow becomes restricted due to the formation of ice cubes in the ice forming cells 46A and 46B, the water flow probe 153 in the second chamber 134 will lose contact with the water. The control unit 152 turns off the water pump 38 and opens the hot gas solenoid 170. As the ice cubes fall from the evaporator 48 and into the storage bucket, the ice damper switch 63 will open and it will be closed again several times. Twenty seconds after the last time the ice damper switch 63 opens, the control unit 152 closes the hot gas solenoid 170, and starts a condenser fan motor (not shown), the water pump 38, and water inlet valve 151. Water pump 38 fills the water distributor, evaporator, and water collection unit with water from the sump. Water continues to flow into water sump 38 through inlet valve 151.

When water comes into contact with the sump sensor 66 for the first time, the water pump 38 is turned off. After turning off the water pump 38, the water from the distributor, the evaporator, and the water collection unit flows rapidly back to the water sump 36. During this operation, the water overflows the riser 146 and starts the effect. siphon, and the water is continuously siphoned from the water sump 36 by the sump 64 drainage system.

Water is siphoned from water sump 36 much faster than water is drawn into water sump 36 through inlet valve 151. In one embodiment of the invention, water is siphoned through the system sump drain 64 at about one to about two gallons per minute, and water flows through inlet 151 at a rate of about 0.25 gallons per minute. Consequently, the water is drained from the water sump 36 and exposes the sump sensor 66. When the water level drops below the bottom of the cap 144, the air enters the riser 146 and the siphon it stops. Water continues to flow into water sump 36 through inlet 151, thereby raising the water level in water sump 36 once again.

10

When the water contacts the sump sensor 66 a second time, the water pump 38 is started again. The water pump 38 pumps back into the water distributor, the evaporator, and the water collection unit, causing the water level in the water sump 36 to drop and exposing the sump sensor 66. Water continues to flow into the water sump 36 through the inlet valve 151 constantly raising the water level in the water sump 36. When the water in the sump contacts the sump sensor 66 a third Once, the water inlet valve 151 is closed. The icemaker is now in another freeze cycle.

If the ice damper switch 63 remains open for twenty consecutive seconds, the control unit 152 determines that the ice bucket is full and the ice is holding the damper 58 open. The control unit 152 then places the icemaker in the automatic shutdown mode described above.

If, after three hundred seconds into a harvest cycle, the ice damper switch 63 fails to open at least once, the control unit 152 will abort the harvest cycle and return the ice machine to a freeze cycle. .

When the ice damper switch 63 is closed again, if the ice machine has been off for three hundred seconds, the control unit 152 initiates the start-up sequence described above. If the ice machine has not been off for three hundred seconds, and the ice damper switch 63 is closed again, the control unit 152 delays start-up again until the three hundred second time period has elapsed. This period of time can be canceled by moving the master control switch to the "OFF 'position and back to the" ON "position.

When the machine is initially powered up, or the master control switch is moved from the "OFF 'or" CLEAN "position to the" ON "position, the count for the start of the pick cycle type starts at" 1 ". If the icemaker is turned off in an automatic shutdown mode, the control unit 152 stores the count sequence of the harvest cycle in memory and continues the count after restarting.

Those skilled in the art will understand that a flush cycle can be performed in various phases during operation of the ice machine. The need for a flush collection cycle will vary depending on the quality of the water fed into the ice machine. For example, instead of every fourth cycle, where there is a high concentration of minerals in the feed water, the flush cycle can be performed more frequently. Alternatively, when supplying high purity water to the ice machine, a water flush cycle can be performed less frequently than every fourth collection cycle. The icemaker will be more efficient if the flush pickup cycle is less frequent because a new batch of hot water will not have to be cooled as often. If the mineral content is too high, however, the quality of the ice will deteriorate.

Cleaning cycle

When the master control switch is set to the "CLEAN" position, the control unit 152 cycles through a programmed cleaning and rinsing cycle. A summary of the operational sequence is provided in the table shown in Figure 14.

When the master control switch is moved to the “CLEAN” position the cleaning sequence starts immediately. If the switch is returned to the “OFF” or “ON” position within the first thirty seconds, the cleaning cycle is canceled. After the first thirty seconds the cleaning cycle is closed, the ice machine should complete the cleaning cycle. The icemaker will shut down if the master control switch is moved to the "OFF" position, and will then continue with the remaining portion of the cleaning cycle when the master control switch is moved to the "ON" or "CLEAN" position. ”. After the sawing period has started, the master control switch can be moved to the “ON” position, and the ice machine will return to the ice-making mode after the cleaning cycle is complete. The close feature can be canceled by moving the master control switch from the “OFF” position to the “ON” position three times in a period of ten seconds or less.

Therefore, it is clear that a low volume ice making machine has been described in accordance with the invention which fully provides the advantages shown above. The preferred ice machine of the invention produces large, individual, clear ice cubes that can be handled by tongs and are therefore desirable for residential use. The ice machine can easily be manufactured from inexpensive injection molded plastic parts that can be formed to fit together. The metal parts of the evaporator can be easily manufactured using an automated metal forming and stamping process. The evaporator design offers high reliability and requires infrequent maintenance. Additionally, the stacking feature of the evaporator design allows ice capacity to be increased without increasing the area of the ice machine base.

eleven

Those skilled in the art will recognize that numerous modifications and variations can be made without departing from the scope of the invention. For example, the ice machine can include various types of electronic control devices, such as microprocessor devices, micro-controller devices, programmable logic devices, and the like. As described above, the collection cycle with flushing, rather than

5 if set to occur every quarter or other fixed number of cycles, it could be started after a variable number of cycles, which number can be set differently on each machine to take into account the conditions of the water supplied to a particular machine. Accordingly, all such variations and modifications are intended to be included within the scope of the appended claims.

10

12

Claims (1)

(to)

an evaporator (48) having a plurality of individual ice-forming cells (46), each cell (46) having a closed perimeter and an opening at a lower end; Y

(b)

a water disperser (74) comprising a first tube section (100) and an inclined section

(106) at an upper end of each of the plurality of individual ice-forming cells (46), and a baffle plate (108), characterized by a second tube section (104) downstream of the first tube section ( 100) and connected to the first tube section (100) by the inclined section (106), wherein a diameter of the second tube section (104) is greater than a diameter of the first tube section (100), and wherein the second tube section (104) is coupled to the upper end of the ice-forming cell (46), and wherein the baffle plate (108) is located within the water disperser (74) and aligned with a transition point (112) between the first tube section (100) and the inclined section (106) and attached to an internal wall of the first tube section (100) by L-shaped arms (114) that join the baffle plate (108) to the inner wall of the first tube section (100), the baffle plate (108) having a surface s upper surface and a lower surface (110), and wherein the lower surface (110) of the baffle plate (108) aligns with the transition point (112) between the first tube section (100) and the inclined section ( 106), so that the flow of water that comes into contact with the baffle plate passes between the baffle plate and the L-shaped arms and is evenly dispersed on an inner wall of the second tube section.

two.

Ice machine of claim 1, wherein the baffle plate (108) is connected to the first tube section (100) by the L-shaped arms (114), so that the baffle plate (108) is positioned downstream from a point of attachment of the L-shaped arms (114) on an internal wall of the first tube section (100).

3.

Ice maker of claim 1 or claim 2, wherein the evaporator (48) further comprises:

(a) a thermally conductive plate (70) extending in the foreground, wherein each of the plurality of ice-forming cells (46) is located within the thermally conductive plate (70), and wherein each cell (46) has a longitudinal axis extending in a direction substantially perpendicular to the first plane; Y (b) a heat transfer conduit (52) attached to the thermally conductive plate (70) in the vicinity of each of the plurality of individual ice-forming cells (46).

Four.

Ice machine of claim 3 wherein the thermally conductive plate (70), the ice-forming cells (46), and the heat transfer conduit (52) comprise copper metal.

5.

Ice maker of claim 1 or claim 2, wherein the evaporator (48) further comprises:

(to)

a first thermally conductive plate (70);

(b)

a second thermally conductive plate (72) below the first thermally conductive plate (70); Y

(c)

a heat transfer conduit (52) attached to the first and second thermally conductive plates (70, 72) in the vicinity of each of the plurality of individual ice-forming cells (46),

wherein each of the plurality of ice-forming cells (46) comprises a first cell (46A) located within the first thermally conductive plate (70) and a second cell (46B) located within the second thermally conductive plate ( 72), and wherein the first and second cells (46A, B) are connected together by a thermally insulating coupler (76).

6.

Ice machine of claim 5 wherein the thermally insulating coupler (76) comprises injection molded plastic having lower water absorption and a lateral dimension substantially equal to a lateral dimension of the first and second cells (46A, B).

7.

Ice machine of claim 3 or 5, wherein the ice-forming cells (46) and the heat transfer conduit (52) are welded to the thermally conductive plate (70).