US2982111A - Ice level sensing mechanism - Google Patents

Description

y 1961 R. R. DAHL 2,982,111

ICE LEVEL SENSING MECHANISM Filed Oct. 28. 1959 3 Sheets-Sheet 1 Ezzazztczr Faber? R. Dab/ y 1961 R. DAHL 2,982,111

ICE LEVEL SENSING MECHANISM Filed Oct. 28, 1959 s Sheets-Sheet 2 E2227 far Robert R. Dah/ R. R. DAHL ICE LEVEL SENSING MECHANISM May 2, 1961 3 Sheets-Sheet 3 Filed Oct. 28, 1959 g? g r Erin far Rebel-f R. Dab/ United States Pate t.

2,982,111 ICE LEVEL SENSING MECHANISM Robert R. Dahl, Lincolnwood,lll., assignor to The Dole Valve Company, Morton Grove, IlL, a corporation of Illinois Filed Oct. 28, 1959, Ser. No. 849,201 4 Claims. (CL 62-137) This invention relates to automatic ice making devices of the type which are adapted to be installed within the freezing compartments of usual household refrigerators and more particularly relates to a mechanism for controlling the cyclic operation of such an ice making device as a function of the level of frozen ice blocks disposed within a collection tray.

This invention is directed to an improvement in a pivotal or rotatable type of ice tray such as the type wherein the ice tray is constructed with a plurality of ice molds formed therein facing in different directions and having common walls which are so arranged that upon filling of an upwardly facing mold with relatively warm water, heat will be transferred from the water filling the up wardly facing mold to the surfaces of a downwardly facing mold through the heat conducting wallsof the ice tray to effect gravitational ejection of the ice blocks from the downwardly facing molds.

The ice block sensing mechanism, to which this invention is especially directed, comprises generally a sensing lever which is pivotally mounted on the shaft upon which the ice tray itself is rotated, which is adapted to have relative movement on the shaft with respect to the ice tray. Connected to the ice sensing lever for corotatable movement therewith is a cam which, in turn, is cooperable with the depressible plunger of an electrical switch to actuate the switch upon rotation of the cam.

A spring serves to interconnect the ice tray with the ice sensing lever so that the two members normally move corotatably with one another. The sensing lever is, however, so arranged that when the ice blocks within the collection tray reach a predetermined level, the ice sensing lever will be prevented from rotating even though urged to do so through the spring means interconnecting the lever with the rotating ice tray. Such relative movement between the sensing lever and the ice tray is operable to position the cam to move the plunger of the electrical switch to a depressed position thereby preventing subsequent energization of the motor for rotating the ice tray and energization of the electrically controlled valve means for filling the upwardly facing molds within the ice tray. The switch which is actuated upon relative movement of the sensing arm relative to the ice tray does, in fact, constitute a line switch; the actuation of i which controls the energization of the entire ice making apparatus.

It is therefore a principal object of the present invention to provide an improved means of controlling the cyclic operation of an automatic ice making apparatus as a function of the level of ice blocks within an ice block collection tray.

Another object of the invention resides in the provision of an ice level sensing arm which is normally corotatable with a rotatable or pivotal type of ice tray and in which relative movement of the ice tray and the sensing arm caused by abutment of the sensing arm with ice blocks at a predetermined level is operable to actuate an electrical switch to deenergize the entire ice making assembly.

Yet another object of the invention is the provision of adevice which is operable to control the operation of an ice making apparatus as a function of the level of ice blocks within an ice block collection tray wherein the 2,982,l l l Patented May 2, 1961 sensing member is disposed out of the path of movement of ice blocks being ejected from the ice tray.

These and other objects of the invention will become apparent from time to time as the following specification proceeds and with reference to the accompanying drawings, wherein:

Figure l is a side elevational view of an ice making apparatus constructed in accordance with the principles of the present invention which, for clarity, shows some of the parts in vertical section;

Figure 2 is a vertical sectional view through the ice tray and the associated ice level sensing member in a first position; 1

Figure 3 is a vertical sectional view through the ice tray and its associated ice level sensing member which illustrates the position of the associated components when the ice blocks within the collection tray have reached the level at which it is desired to discontinue operation of the ice making assembly;

Figure 4 is a view taken in the direction of lines lV-IV of Figure 2 which -illustrates the cam surface operable to control the operation of the switch means for energizing and deenergizing the entire ice maker assembly; and

Figure 5 is a schematic circuit diagram of an electrical circuit such as might be employed in controlling the operation of such an ice making apparatus.

Referring initially to Figures 1 and 2, a pivotal ice tray 10 is mounted on a shaft 11 for corotatable movement therewith, which shaft is in turn journalled for pivotal movement in an insulated sidewall 12 of a freezing compartment of the usual household refrigerator or the like. A motor or power means 13 is diagrammatically illustrated as being connected to the input end of the shaft 11 and may be of any suitable type which can effect a preselected angular movement of the shaft 11 and tray 10 at preselected intervals of time.

The ice tray 10 comprises generally a confining wall 15 which has outwardly turned ends 16 and 17 formed integrally therewith and at opposite ends thereof and which is bent along its longitudinal axis as at 18 to form two elongated oppositely facing legs 19 and 20.

A common wall 21 (so called because it is common to ice molds formed on opposite sides thereof as will hereinafter be more clearly described) constitutes an obtuse bisectrix of the elongated legs 19 and 20 and extends from the vertex 1% of those legs and is secured at opposite ends thereof to the upstanding end walls 16 and 17.

The common wall 21 has elongated slots formed therein (not shown) which fit within grooves (not shown) formed in a plurality of equally spaced upstanding partitioning walls or fins 24, which, in turn, seat upon the legs 19 and 20 and which serve to divide the ice tray 10 into 0 a plurality of separate ice molds.

It will be understood that in the class of ice trays to which this invention is directed, it is desirable to form each of the components of the icetray of a good heat conducting material inasmuch as ejection of ice blocks from a plurality of downwardly facing molds is effected by breaking the bond between those ice blocks and the walls of their respective molds by heat transmitted thereto through the walls of the ice tray from the relatively warm water filling an upwardly facing mold.

Elongated retaining walls 27 and 28 are formed along the outer longitudinal edges of the legs 19 and 20 and lie substantially in planes parallel to the plane of the common wall 21. cooperation with the legs 19 and 20 constitute drip retainers for containing drops of water running off the ice blocks subsequent to the melting of the surfaces of those blocks for preventing this water from flowing to the ice These elongated retaining walls in block collection tray and to thereby prevent sticking of the ice blocks subsequent to their ejection into the collection tray. The collection tray is fragmentarily illustrated in Figure 2 at 29 and may comprise any suitable storage basket which may be positioned beneath the ice tray to collect the ice blocks ejected therefrom.

The edge portions of the partitioning walls 24 lie substantially along planes parallel to but spaced from the planes of the edge portions of the ends 16 and 17 of the pivotal ice tray but are inturned and meet at a vertex spaced a substantial distance from the outer longitudinal edge of the common wall 21. Also, the edges of the partitioning walls are cut back adjacent the drip retainers so that water dripping off each of several ice blocks in a downwardly facing mold will be comingled with water dripping from each of the other blocks. Furthermore, in order to facilitate gravitational ejection of the frozen ice blocks from their respective molds the side walls of the fins 24 taper outwardly on each side of the ice molds.

Thus, when water is directed to a single ice mold, water will flow around the partitioning walls 24 in the trough 33 formed intermediate the inturned edge portions of the partitioning walls 24 and the outer longitudinal edge of the common wall 21 to thereby fill each of the upwardly facing molds communicable with the mold initially filled, through the troughs.

Assuming that the ice tray 10 is initially disposed in the position illustrated in Figure 2 with the leg 19 disposed at approximately 40 with respect to the horizontal, the ice tray 10 can be rotated in a clockwise direction through the power source 13 until the ice tray is disposed in the position illustrated in Figure 3 wherein the leg 20 is disposed at an angle of approximately 40 with respect to the horizontal. At such time filling of the upwardly facing bank of ice molds might be effected by directing relatively warm water to those molds in a manner which will hereinafter be described. Heat will then be transmitted from the water in the upwardly facing molds through the common wall 21 to melt the surfaces of the ice blocks bonded thereto and will also be conducted through the partitioning walls 24 and the end walls 16 and 17 and further through the leg 19 of the confining wall 15 so that the bond between the ice blocks and the walls of the individual downwardly facing molds will be broken to permit their gravitational ejection.

Upon melting of the ice blocks within the respective downwardly facing molds, the ice blocks will cease to adhere to the walls of the ice tray and will fall by the force of gravity from the ice tray into the collection tray 29. Drops of water flowing from the surfaces of the ice block's, subsequent to the melting thereof, will flow to the drip retainer 27 where they will be retained and prevented from dripping to the ice block collection tray 29.

Upon freezing of the water in the upwardly facing molds 25 into ice blocks the cycle can then be repeated and the ice can then similarly be rotated in a counterclockwise direction until the leg 19 is again disposed at an angle of approximately 40 with respect to the horizontal. Subsequent to rotation of the ice tray in this manner the water disposed within the drip retainer 27 will freeze and will then flow back into the bottom of the individual upwardly facing ice molds upon meltingthereof by the water filling those molds where it will again be refrozen along with the water used to fill the upwardly facing bank of ice molds.

The device used for filling the upwardly facing bank of ice molds comprises a slug valve having an inlet 36 and an outlet 37. The slug valve is mounted on the side wall 12 of the freezing compartment by means of a bracket 38 which is connected to that wall and which is similarly secured to the slug valve 35. A pair of solenoids 39 and 40 are mounted on the slug valve 35 and are operable to control fluid flow through the inlet 36 and outlet 37, respectively. Upon energization of the inlet solenoid 39 pressurized fluid is permitted to enter a measuring chamber of desired volumetric capacity within the slug valve body through the inlet 36. Thereafter, by deenergizing the solenoid 39 to close the inlet port and by energizing the solenoid 40 to open the outlet 37 and thereafter decreasing the volumetric capacity of the fluid chamber within the slug valve body fluid will be forced through the outlet 37. Since the particular manner in which the slug valve functions constitutes no part of the present invention the slug valve is neither shown nor dcscribed in detail. It will be noted, however, that a filler spout 41 is communicable with the outlet 37 from the slug valve 35 and extends through the side wall 12 and terminates at a point above the ice tray 10 to provide a means for filling the tray with a measured quantity of liquid.

For the sake of clarity, Figure 1 illustrates the ice tray 10 and its associated components in a position wherein the common wall 21 is disposed in a vertical position.

In that view the ice tray 10 is shown as having a shaft 45 affixed thereto for corotatable movement therewith which is disposed at the outer end of the tray 10 and which is coaxially aligned with the drive shaft 11.

An ice sensing arm or lever 50 depends from the ice tray 10 and has a pair of outwardly extending legs 51 and 52 which are rotatably mounted on the shafts 45 and 11, respectively. It will be noted that the sensing arm 50 is so disposed with respect to the collection tray 29 that the lowermost'edge of the sensing arm is movable through the upper portion of the collection tray. The sensing arm 5%} may, however, be positioned closer to or farther away from the surface of the collection tray 29 as desired; the relative position of the arm with respect to the tray being determinative of the level of ice blocks to be dumped into the tray as will hereinafter become more fully apparent.

As shown most clearly in the wiring diagram illustrated in Figure 5, energization of the motor 13, solenoids 39 and 40, and the water heater coil 40a (disposed within the slug valve) is effected through a master switch 70. The heater coil, not heretofore mentioned, is utilized to heat the water prior to its delivery to the ice tray and is additionally energized through a selector switch 69. The switch 69 is also operable to control energization of the slug valve solenoids 39 and 40 to control the delivery of water to the ice tray 10.

The switch 70 has a movable contact 71 which is normally biased into engagement with a pair of stationary contacts 72 by means of one or more compression springs 73. The switch 70 is contained within a casing 74 and has a plunger 75 slidably mounted within the casing and extending exteriorly thereof which is connected to the movable contact 71 and which is operable, upon depressional movement thereof, to move the contact 71 out of engagement with stationary contacts 72 to break the circuit through the switch.

An arcuately shaped cam support 60 is rotatably mounted on the shaft 11 and is keyed to the sensing arm 50 for corotatable movement with the sensing arm. A cam 61, arcuately shaped in side elevation, is afiixed to the cam support 60 by means of a pair of screws 62 and, as shown in Figure 4, has high plateaus 63 and 64 disposed on opposite sides of a recess 65.

The casing 74 of the electrical switch 79 is mounted by means of a bracket 77 to the output shaft 11 of the power source 13 for corotatable movement therewith so that the switch will rotate with the ice tray 10. The switch 70 is so disposed that the outermost end of the plunger 75 is disposed in juxtaposition to the cam 61 so that pivotal movement of the cam relative to the switch will be effective to longitudinally move the plunger 75 to operate the switch.

It will be understood that during the normal cyclic operation of the ice making apparatus, the ice tray 10 will pivotally move from the position illustrated in'Figure 2 to the position illustratedin Figure 3 and thence back again to the position illustrated in Figure 2. Such in a coplanar position with respect to the common wall 21 and similarly is effective to maintain the cam 61 in a position such that the plunger 75 is disposed within the recess 65. Thus, due to the bias of the tension spring 59 the sensing arm 50, ice tray 10, and switch 70 will normally remain in the relative positions illustrated in Figures 1, 2 and 4.

However, when the ice blocks within the collection tray 29 have reached the level illustrated in Figure 3, rotatable movement of the sensing arm 50 from one extreme position to the other will be prevented inasmuch as ice blocks lie in the path of its rotary movement.

Upon energization of the motor 13, pivotal movement of the ice tray and the sensing arm 50 through their prescribed arc will be initiated. When the sensing arm 50 moves into engagement with ice blocks disposed Within the collection tray 29, further pivotal movement thereof will be prevented although the ice tray 10 will continue to rotate. Such relative movement between the ice tray 10 and the sensing arm 50 will act to move the plunger 75 of the switch 70 out of the recess 65 in the cam 61 and onto one of the high plateaus of the cam to depressionally move the plunger 75 with respect to the switch casing 74. Such depressional movement of plunger 75 will act to move the movable contact 71 out of engagement with stationary contacts 72 to break or open the energizing circuit through the switch. When the circuit through the switch 70 is broken the motor 13 will be deenergized and further rotation of the ice tray 10 will be prevented.

It will, however, beunderstood that if the motor used for effecting rotatable movement of the ice tray 10 and its associated components comprises a heat motor or any other similar power source which is hysteretically operable subsequent to the deenergization of its control means, the tray 10 and the associated switch 70 might continue to rotate to an extreme rotated position as is illustrated in Figure 3. If, on the other hand, a simple synchronous motor is used for effecting rotatable movement of the tray 10 and its associated components, pivotal movement of the tray 10 will cease almost at the movement that the circuit through the switch 70 is broken. It will be understood, however, that neither the particular means for effecting rotatable movement of the ice tray or the means for filling the tray with relatively warm fluid constitute elements of the present invention and so they are not herein shown or described in detail.

It will further be understood that this embodiment of the invention has been used for illustrative purposes only andthat various modifications and variations in the present invention may be effected without departing from the spirit and scope of the novel concepts thereof.

I claim as my invention:

1. In combination with an ice making assembly including a support having an ice tray pivotally mounted thereon and disposed within a freezing compartment, control means for rotating the ice tray and ejecting ice blocks therefrom, a collection tray for collecting ice blocks ejected from the ice tray, the improvement of means for operating the control means as a function of the level of ice blocks within the collection tray comprising a sensing element, means mounting said sensing element for pivotal movement with respect to said support for sweeping the surface of the collection tray, resilient means interconnecting said element with the ice tray to urge said element to pivot with the tray but operable to permit relative movement between said element and said tray when pivotal movement of said element is blocked 15 by its engagement with ice blocks during a pivoting cycle of the ice tray, and switch means for controlling energization of the control means operable as a function of the relative position between said element and tray.

2. In combination with an ice making assembly including a support having an ice tray pivotally mounted thereon and disposed within a freezing compartment, control means for rotating the ice tray and ejecting ice blocks therefrom, a collection tray for collecting ice blocks ejected from the ice tray, the improvement of means for operating the control means as a function of the level of ice blocks Within the collection tray comprising a sensing element, means mounting said sensing element for pivotal movement with respect to, said support about the same axis as the ice tray for sweeping the surface of the collection tray, resilient means interconnecting said element with the ice tray to urge said element to pivot with the tray but operable to permit relative movement between said element and tray when pivotal movement of said element is blocked by its engagement with ice blocks during a pivoting cycle of the ice tray, and means for controlling the energization of the control means and operable to deenergize same upon relative movemen-t'between said element and tray.

3. In combination with an ice making assembly ineluding a support having an ice tray pivotally mounted thereon and disposed within a freezing compartment, control means for rotating the ice tray and ejecting ice blocks therefrom, a collection tray for collecting ice blocks ejected from the ice tray, the improvement of means for operating the control means as a function of the level of ice blocks within the collection tray comprising a sensing element pivotally mounted on the ice tray at the pivotal axis of the ice tray for sweeping the surface of the collection tray, a resilient drive connection between the ice tray and said sensing element operable to resiliently maintain said element and the ice tray in a fixed position relative to one another but operable to prevent relative movement between said element and tray when pivotal movement of said element is blocked by its engagement with ice blocks during a pivoting cycle of the ice tray, and switch means for controlling energization of the control means actuatable to a deenergizing position upon relative movement between said element and tray.

4. In combination with an ice making assembly including a support having an ice tray pivotally mounted thereon and disposed within a freezing compartment, control means for rotating the ice tray and ejecting ice blocks therefrom, a collection tray for collecting ice blocks ejected from the ice tray, the improvement of means for operating the control means as a function of the level of ice blocks within the collection tray comprising a sensing element pivotally mounted on the ice tray for sweeping the surface of the collection tray, resilient means interconnecting said element with the ice tray to urge said element to pivot with the tray but operable to permit relative movement between said element and tray when pivotal movement of said element is blocked by its engagement with ice blocks during a pivoting cycle of the ice tray, switch means connected to the ice tray and corotatable therewith having a plunger extending therefrom which is reciprocably movable to actuate the switch means, and abutment means forming an extension from said sensing element engageable with said plunger and cooperable therewith to effect reciprocable movement thereof as a function of the relative position of said element and tray.

References Cited in the file of this patent ,808,707 Chase Oct. 8, 1957

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