Ice Preparation Device

Abstract

An ice maker comprises a frame (15) and a tray (1) pivotable in the frame (15) about an axis. The tray (1) has a plurality of compartments (4) which are arranged in a number of rows and separated from one another by partition walls (3) and is pivotable between an upright setting in which the upper edges of the partition walls (3) extend horizontally, an emptying setting in which the openings of the compartments (4) face downwardly and a tilted setting in which a predetermined water quantity filled into a row of the tray (1, 1′, 1″) in part floods over the upper edges of the partition walls (3) between the compartments (4) of the row whilst after pivotation back into the upright setting the partition walls (3) separate the part quantities, which are distributed to the compartments (4), of the water quantity from one another.

Description

The present invention relates to an ice maker comprising a frame and a tray which is pivotable in the frame about an axis and which has a plurality of compartments arranged in a number of rows and separated from one another by partition walls. Such an ice maker is known from, for example, U.S. Pat. No. 6,571,567 B2.This conventional ice maker is pivotable from an upright setting in which the upper edges of the partition walls between the compartments extend horizontally into an emptying setting in which the openings of the compartments face downwardly, so that the finished pieces of ice can drop out of them.

A stationary feed pipe which is arranged above the tray serves for filling the compartments with water. Water from this feed pipe initially fills one of the compartments of the tray and the other compartments of the tray fill with water only in sequence when the respective compartments lying close to the directly filled compartment begin to overflow. Inaccuracies in the metering of the water quantity therefore do not lead to uniformly distributed fluctuations in the size of all pieces of ice, but have an influence only on the filling state of the compartments most remote from the point of pouring in, whilst the poured-in quantity in the directly filled compartment and compartments adjoining thereto remains unchanged. In order to ensure a complete filling also of the compartments furthest away from the point of pouring in it is necessary to pour in so much water that the partition walls between all compartments are flooded over. However, this has the consequence that there are obtained not pieces of ice cleanly separated from one another, but a cohesive block similar to a cake of chocolate, which before use has to be broken up into individual pieces.

In order to avoid this disadvantage it would be desirable to be able to produce a uniform distribution of the water between the compartments without the partition walls having to be flooded over. With respect thereto there have already been proposed ice-maker trays in which there are formed in the upper edges of the partition walls respective notches which facilitate overflowing of water from a full compartment to an adjacent compartment still capable of receiving. However, here too the problem results that a uniform distribution of water to the compartments is not achieved as long as the water-filled cross-section of the notches is so small that the surface tension influences the throughflow of water and that if the cross-section of the notches is increased in order to reduce the influence of the surface tension cohering pieces of ice are obtained.

The object of the present invention is to indicate an ice maker which makes it possible by simple means to achieve individual pieces of ice of uniform dimensions reliably separated from one another or which makes it possible to produce pieces of ice of uniform dimensions even when the water quantity admetered in each working cycle of the ice maker is not exactly matched to the receiving capacity of the ice-maker tray.

The object is fulfilled by an ice maker comprising a frame and a tray pivotable in the frame about an axis, wherein the tray has a plurality of compartments arranged in a number of rows and separated from one another by partition walls and is pivotable between an upright setting in which the upper edges of the partition walls extend horizontally and an emptying setting in which the openings of the compartments face downwardly, and in which the tray is further pivotable into a tilted setting in which a predetermined water quantity filled into compartments of a row of the tray in part floods over the upper edges, which have an inclination in this setting, of the partition walls between the compartments of the row and thus ensure an identical water level in all compartments, whilst after pivotation back into the upright setting the partition walls separate the part quantities, which are distributed to the compartments, of the water quantities from one another.

The water quantity with which this effect is achievable is predetermined by the dimensions of the tray and its compartments and is thus a characteristic of the tray.

The above-described possibility of producing uniform distribution of the water between the compartments is absent in the case of U.S. Pat. No. 6,571,567 B2 stated in the introduction. Here, too, the tray does indeed pass, between its upright setting and the emptying setting, through an intermediate setting in which, presupposing a suitable profile of the longitudinal walls of the tray, a partial flooding over of partition walls into a lower disposed one of the two rows of the tray could take place, but in this setting water would at the same time flow out of the higher disposed one of the two rows into the lower disposed one so that equalisation between the compartments of the higher disposed row is not possible and instead thereof there is the risk of overflowing of the lower disposed row.

The simplest possibility of creating such a volume equalisation for all compartments of the ice-maker tray is to form this with a single row of compartments.

However, it is also possible to provide several rows of compartments adjacent to one another, wherein in this case a separating wall between the rows, which is higher than the partition walls between the cells of the row, prevents overflowing of water from one which is disposed higher in the tilted setting to one which is disposed lower.

Preferably, the tilted setting and the emptying setting can be reached from the upright setting by pivotation in opposite directions. Such a construction leads to a simple course of movement during operation of the ice maker, since during an ice-producing cycle the tray does not have to change its pivot direction when it is transferred from the tilted setting in which the volume equalisation is produced, to the upright setting in which the water is frozen in the cells and finally to the emptying setting.

It is possible to let the tray further rotate from the emptying setting, which maintenance of the sense of rotation, until it reaches the tilted setting again and can be refilled in this setting. Such a course of movement can be realised by a particularly simple drive mechanism.

However, according to preference the tray is driven to oscillate, since this enables realisation of the course of movement in a smaller space.

In that case the tilted setting and/or the emptying setting each time preferably represent a point of reversal of the oscillatory movement.

The use of a transmission which converts a drive movement of like sense into an oscillatory movement of the tray makes it possible to use as drive unit for the movement of the tray an economic motor, which is simple to control, with a single sense of rotation.

Due to the fact that a wall extending above the upper edge of the partition walls is preferably formed at a longitudinal side of each row of compartments as well as at at least a part of the transverse sides thereof the possibility is created, by an inclined setting of the tray, of enabling crossing of water from one compartment to another over a large cross-sectional area substantially uninfluenced by surface tension effects, so that the same water states result in each compartment, and, by subsequent placing of the tray upright, of cleanly separating the water bodies in the individual compartments from one another so that non-cohering pieces of ice are obtained when freezing.

In order to achieve, in the inclined state, a sufficient cross-section for the passage of water between the compartments the wall should protrude at least 5 millimetres above the upper edge of the partition walls.

In order to facilitate removal of the finished pieces of ice from the mould the compartments preferably have the shape of a segment of a circle in cross-section. A piece of ice can be removed from these compartments in particularly simple manner in that it slides in circumferential direction of the circle segment without—as in the case of a conventional block-shaped piece of ice of the kind under consideration in, for example, U.S. Pat. No. 6,571,567 B2—formation, during removal from the mould, between the base of the compartment and the ice body of a cavity which prevents removal from the mould as long as there is no equalisation of an underpressure prevailing in the cavity.

An electric heating device can be provided at the ice-maker tray in order to accelerate and facilitate mould removal of finished pieces of ice through thawing at the surface.

In order to achieve an intensive heat exchange with the environment the tray can be provided with protruding exchange heat exchange ribs. These ribs can at the same time serve for mounting a rod-shaped heating device inserted therebetween.

In order to make the ice maker compact, the centre axis of a notional smallest cylinder enclosing the tray is preferably selected as pivot axis.

The upper edges of the partition walls preferably lie above the pivot axis in the upright and the tilted setting. A large cross-sectional area of the compartments with, at the same time, compact external dimensions of the ice maker can thereby be realised.

Further features and advantages of the invention are evident from the following description of examples of embodiment with reference to the accompanying figures, in which:

FIG. 1 shows an exploded illustration of an automatic ice maker according to a preferred embodiment of the invention;

FIG. 2 shows a perspective view of the ice maker according to FIG. 1 in assembled state with ice-maker tray in tilted setting;

FIG. 3 shows a front view of the ice maker of FIG. 1 or 2 in the direction of the pivot axis;

FIG. 4 shows the view of FIG. 3 with partly cut-away sensor housing;

FIG. 5 shows a view, which is analogous to FIG. 2, with ice-maker tray in upright setting;

FIG. 6 shows a view, which is analogous to FIG. 4, with the ice-maker tray in upright setting;

FIG. 7 shows a perspective view analogous to FIGS. 2 and 5 with the ice-maker tray in emptying setting;

FIG. 8 shows a view analogous to FIG. 4 or 6;

FIG. 9 shows a perspective exploded view from below of the ice-maker tray;

FIG. 10 shows a schematic section through an ice maker according to a second embodiment, in upright setting;

FIG. 11 shows a sectional through the ice maker of FIG. 10 in tilted setting; and

FIG. 12 shows a perspective view of a modified tray for an ice maker.

FIG. 1 shows an automatic ice cube maker according to the present invention in an exploded perspective view. It comprises a tray 1 in the form of a channel with a semi-cylindrical base, which is closed at its ends by respective transverse walls 2 and is divided by partition walls 3, which are arranged at uniform spacings, into a plurality of identically shaped compartments 4, here seven units, with a semi-cylindrical base. Whereas the partition walls 3 at the longitudinal wall 5 remote from the viewer adjoin flushly, the longitudinal wall 6 facing the viewer is prolonged above the upper edges of the partition walls 3. Whilst the partition walls 3 are exactly semicircular, the transverse walls 2 each have a sector 7, which goes out above the semicircular shape, in correspondence with the protrusion of the front longitudinal wall 6.

The tray 1 is shown in a tilted setting in which the upper edges of the segments 7 extend substantially horizontally, whilst those of the partition walls 3 are inclined towards the longitudinal wall 6.

The tray 1 can be a plastics material moulded part, but preferably, due to the good capability of thermal conductance, it is constructed as a cast part of aluminium.

A hollow cylinder 11 is mounted at one of the transverse walls 2 of the tray 1; it serves for protected accommodation of a coiled power supply cable 12 serving for supply of current to a heating device 13, which is not visible in the figure, accommodated at the underside of the tray 1 (see FIG. 9). The tray 1 lies completely within a notional prolongation of the circumferential surface of the hollow cylinder 11, which at the same time represents the smallest possible cylinder into which the tray fits. An axial spigot 14, which protrudes from the transverse wall 2 facing the viewer, extends on the longitudinal centre axis of the hollow cylinder 11.

A frame moulded from plastics material is denoted by 15. It has an upwardly and downwardly open cavity 16 which is provided for mounting of the tray 1 therein. Bearing bushes 19, 20 for the pivotable mounting of the tray 1 are formed at the end walls 17, 18 of the cavity 16. A longitudinal wall of the cavity 16 is formed by a box 21, which is provided for reception of a drive motor 22 as well as various electronic components for control of operation of the ice maker. Mounted on the shaft of the drive motor 22 is a pinion 23 which can be seen better in each of FIGS. 3, 4, 6 and 8 than in FIG. 2. When the ice maker is in fully mounted state the pinion 23 finds space in a cavity 24 of the end wall 17. It forms there, together with a gearwheel 25, a speed step-down transmission.

The gearwheel 25 carries a pin 26 which protrudes in axial direction and which is provided for engaging in a vertical slot 27 of an oscillatory body 28. The oscillatory body 28 is guided to be horizontally displaceable with the help of pins 29 which protrude from the end wall 17 into the cavity 24 and which engage in a horizontal slot 30 of the oscillatory body. A toothing 31 formed at a lower edge of the oscillatory body 28 meshes with a gearwheel 32, which is provided for the purpose of being plugged onto the axial spigot 14 of the tray 1 to be secure against rotation relative thereto.

A cover plate 33 screw-connected to the open side of the end wall 17 closes the cavity 24. A fastening flange 34 with straps 35 protruding laterally beyond the end wall 17 serves for mounting the ice maker in a refrigerating appliance. A base plate 36 closes the box 21 at the bottom.

FIG. 2 shows, as seen from the side of the end wall 18 and the box 21, the ice maker with the tray 1 in tilted setting in perspective view. The upper edges of the sectors 7 at the transverse walls 2 of the tray 1 extend horizontally.

FIG. 3 shows a front view of the ice maker from the side of the end wall 17, wherein cover plate 33 and fastening flange 34 have been omitted in order to give free view into the cavity 24 of the end wall 17. The configuration shown here is that in which the ice maker is mounted together. Various markings indicate a correct positioning of individual parts relative to one another. A first pair of markings 37, 38 is disposed at the end wall 17 itself, or at the gearwheel 25 carrying the pin 26. When these markings 37, 38 are, as shown in the figure, aligned exactly with one another the pin 26 is disposed in a 3 o'clock setting, i.e. on the point, which lies furthest to the right in the perspective view of the figure, of its path which it can reach. The oscillatory body 28 plugged onto the pin 26 as well as onto the stationary pin 29 is disposed at the righthand reversal point of its path.

Markings 39, 40, which are aligned with one another, at a flange 41 of the gearwheel 32 protruding beyond the tooth rim and at the end wall 17 indicate a correct orientation of the gearwheel 32 and as a consequence thereof also of the tray 1 engaging by its axial spigot 14 in a cut-out, which is T-shaped in cross-section, of the gearwheel 32. A pair, which is redundant per se, of markings 42, 43 at the toothing 31 of the pivot body 28 and at the gearwheel 32 show the correct positioning of gearwheel 32 and oscillatory body 31 with respect to one another.

A sensor 44 for detecting the rotational setting of the gearwheel 32 is mounted near this. It co-operates with a rib 45, which protrudes in axial direction from the edge of the flange 41 on a part of the circumference thereof so that it can enter into a slot at the rear side of the sensor housing. In the tilted setting of FIG. 3 the rib 45 is for the greatest part covered by the sensor 44 and the oscillatory body 28. FIG. 4 differs from FIG. 3 in that the housing of the sensor 44 is shown in part cut away so that two light barriers 46, 47 bridging over the slot can be recognised in its interior. The rib 45 is disposed closely above the two light barriers 46, 47 so that a control electronic system, which is not illustrated, can recognise, on the basis of the fact that the two light barriers are open, that the tray 1 is disposed in the tilted setting and can stop the drive motor 22 in order to be able to keep the tray 1 in the tilted setting and fill it.

After a predetermined water quantity has been admetered to the tray 1 under the control of the control circuit the drive motor 22 is set in operation by the control unit in order to bring the tray 1 into the upright setting in which the water quantities in the compartments 4 of the tray 1 are cleanly separated from one another. This setting is shown in FIG. 5 in a perspective view corresponding with FIG. 2 and in FIG. 6 in a front view corresponding with FIG. 4. The gearwheel 25 is further rotated in clockwise sense relative to the setting of FIG. 4, although the same setting of the tray 1 can also be reached by rotation of the gearwheel 25 in counter-clockwise sense. Attainment of the upright setting is recognised when the rib 45 begins to block the lower light barrier 47.

The tray 1 remains in the upright setting for such a length of time until the water in the compartments 4 is frozen. The dwell time in the upright setting can be fixedly predetermined; alternatively, the control circuit can also be connected with a temperature sensor in order to be able to establish, on the basis of a measured temperature in the environment of the tray 1 and a characteristic curve stored in the control circuit, a respective time period sufficient in the case of the measured temperature for freezing the water.

After expiry of this time period the drive motor 22 is set back into operation in order to rotate the gearwheel 25 into the setting shown in FIG. 8, with the pin 26 in the 9 o'clock position. The control circuit recognises that this position is reached when the two light barriers 46, 47 are again open. The rib 45 is now able to be clearly seen in the figure for a major part of its length.

In this setting the compartments 4 of the tray 1 are downwardly open so that the pieces of ice contained therein can drop out. The already mentioned electric heating device 13 is provided in order to facilitate release of the pieces of ice. As can be recognised in FIG. 9, this heating device 13 is an electric heating rod, which is bent into a loop and which extends in close contact with the tray 1 between heat exchange ribs 49 protruding at the underside thereof and is in part received in a groove 48 formed at the underside of the tray 1.

Through brief heating of the tray 1 with the help of the heating device 13 the pieces of ice in the compartments 4 are thawed at the surface. The water layer thus produced between the tray 1 and the pieces of ice acts as a slide film on which the pieces of ice are movable with very low friction. By virtue of the cross-sectional shape of the compartments 4 in the form of a segment of a cylinder the pieces of ice easily slide out of the compartments 4 and drop into a collecting container (not illustrated) arranged below the ice maker.

After emptying of the compartments 4, the drive motor is set back into operation and the gearwheel 25 further rotated in clockwise sense until it again reaches the setting shown in FIGS. 2 to 4 and a new operating cycle of the ice maker begins.

FIGS. 10 and 11 show schematic sections through a second embodiment of the ice maker with a section plane oriented perpendicularly to the pivot axis of the tray 1′. The tray 1′ is here constructed in the manner known per se with—in the upright setting illustrated in FIG. 10—upper edges, which are overall of the same height, of the partition walls 3. A longitudinal wall 6′ of the tray 1′ bears closely against a stationary wall member 8.

In the tilted setting of FIG. 11 water 10 floods over, only in part, the upper edges of the partition wall 3 between the individual compartments of the tray 1′, so that the water state between the compartments equalises, but also the upper edge of the longitudinal wall 6′. Flowing away is prevented by the wall member 8 bearing closely against the longitudinal wall 6′.

FIG. 12 shows a perspective view of a tray 1″ with two rows of compartments 4. The row remote from the viewer has a longitudinal wall elevated above the partition walls 3, as already described for the example of embodiment of FIG. 1. A longitudinal separating wall 9 between the rows is here too correspondingly elevated and in a tilted setting of the tray 1″ prevents overflowing of water from one row to the other.

Claims

1-13. (canceled)

14. An ice maker comprising: a frame;a tray pivotable in the frame about an axis and having a plurality of compartments with openings and arranged in a number of rows and separated from one another by partition walls, the tray being pivotable between an upright setting, in which the upper edges of the partition walls extend horizontally, and an emptying setting, in which the openings of the compartments face downwardly; andwherein the tray is additionally pivotable into a tilted setting in which a predetermined water quantity filled into a row of the tray in part floods over the upper edges of the partition walls between the compartments of the row whilst after pivoting back into the upright setting the partition walls separate the part quantities of the water quantity from one another, which are distributed to the compartments.

15. The ice maker according to claim 14, wherein the number of rows is one.

16. The ice maker according to claim 14, wherein the tilted setting and the emptying setting can be reached from the upright setting by pivoting in opposite directions.

17. The ice maker according to claim 14, wherein the tray is oscillated.

18. The ice maker according to claim 16, wherein at least one of the tilted setting and the emptying setting is a reversal point of the oscillatory movement.

19. The ice maker according to claim 16, further comprising a transmission associated with the tray for conversion of a drive motion in the same sense into an oscillatory motion of the tray.

20. The ice maker according to claim 14, further comprising a wall extending above the upper edge of the partition walls formed at a longitudinal side of each row of compartments and at least a part of the transverse sides thereof.

21. The ice maker according to claim 20, wherein the wall protrudes at least 5 millimeters above the upper edges of the partition walls.

22. The ice maker according to claim 14, wherein the compartments have the shape of a segment of a circle in cross-section.

23. The ice maker according to claim 14, further comprising an electric heating device.

24. The ice maker according to claim 23, wherein the electric heating device includes a heating rod inserted between heat exchange ribs protruding from the tray.

25. The ice maker according to claim 14, wherein the pivot axis of the tray is the center axis of a smallest cylinder enclosing the tray.

26. The ice maker according to claim 14, wherein the upper edges of the partition walls lie above the pivot axis in the upright and the tilted setting.