US3290892A

US3290892A - Automatic ice making machine

Info

Publication number: US3290892A
Application number: US405358A
Authority: US
Inventors: Henry E Roedter
Original assignee: Individual
Current assignee: Individual
Priority date: 1964-10-21
Filing date: 1964-10-21
Publication date: 1966-12-13
Anticipated expiration: 1983-12-13

Description

Dec. 13, 1966 H, ROEDTER 3,290,892

AUTOMATIC ICE MAKING MACHINE Filed Oct. 21, 1964 2 Sheets-$heet 1 7| 70 N I 69 65 i: l8 Ii 5! 75 O 73 JNVEN TOR.

ll ig j HENRY, E. ROEDTER B ,2 W

ATTORNEY.

2 Sheets-Sheet 2 Filed Oct. 21, 1964 mm .m ON 9 INVENTOR. HENRY E. ROEDTER BY whfl vym ATTOIRNEY United States Patent Ofilice 3,290,802 Patented Dec. 13, 1966 3,290,892 AUTOMATIC ICE MAKING MACHINE Henry E. Roedter, 538 Clinton Springs Ave, Cincinnati, Ohio Filed Oct. 21, 1964, Ser. No. 405,358 Claims. (Cl. 62-137) The present invention relates to ice making machines of the general type shown in US. Patent 2,770,102 issued November 13, 1956. Reference is made to that patent for a complete description of an automatic ice maker of the type which includes a mold for freezing masses of ice (hereinafter referred to as ice cubes). These cubes are ejected from the mold which is subsequently filled with fresh water in preparation for a harvesting cycle during which ice is removed from the mold. The ejection of ice by a combination of heat and pressure is automatically controlled in accordance with the present invention. Further, in accordance with the present invention, there is provided a timer-programming system for controlling the cycle of operation of the automatic ice maker. Among other features the control system in accordance with the present invention includes switches or sensing devices which recognize that the ice has been ejected, all for a purpose hereinafter set forth.

The mold shown in my US. Patent 2,770,102 is secured to a cooled wall, such as the wall of an evaporator, to provide a refrigerated environment. The mold defines a plurality of cavities in which are disposed flexible liners. In FIG. 1 of the present specification the mold is indicated by the reference numeral 39. A typical one of the liners is shown at 47 in FIGS. 2 and 3. When in the FIG. 2 position the liners are filled with water which is frozen by heat transfer. After the ice has frozen a thermostat 36 (FIG. 4) closes a circuit and causes to be energized a heater 45 and a pump 43, 44 which forces working fluid under pressure beneath the liners, thereby ejecting the ice from the molds. The ice cubes are directed to a receptacle or tray 73 where they accumulate until a pivoted detector arm 74, associated with switch 51 (FIG. 4) detects that the tray is full, at which time switch 51 opens to prevent the ejection part of the cycle from occurring. The ice maker resumes operation as soon as the detector arm 74 senses that ice has been removed from the tray 73. After ejection of the ice the liners such as 47 are restored to their water receiving position (FIG. 2) and a supply of fresh Water is directed into the liners under the control of the timer-programmer 30.

The primary object of the invention is to provide, in an automatic ice maker, an improved system for ejecting ice, comprising both heating means and mechanical means working cooperatively.

Another object of the invention is to provide, in an automatic ice making machine, sensing means for determining that all of the ice cubes have been ejected.

Another fundamental object of the invention is to provide an improved timer-programmer and control system for an automatic ice making machine.

For a better understanding of the present invention, together with other and further objects, advantages and capabilities thereof, reference is made to the following description of the appended drawings in which:

FIG. 1 is a perspective view of an improved automatic ice making machine in accordance with the invention;

FIGS. 2 and 3 are end views of the mold 39 and associated elements, featuring liner 47, FIG. 2 showing the liner in water receiving position and FIG. 3 showing the liner in the position it assumes when its mass of frozen Water has been ejected;

FIG. 4 is a schematic diagram, partially in outline form, showing the timer-programmer and control system in accordance with the invention.

Now making reference to FIG. 1, it will be understood that the invention is of primary utility as installed in a domestic refrigerator but it may be used in a home freezer or other type of refrigerator.

The ice making machine includes a mold 39 which defines a plurality of cavities (as shown in detail in FIG. 2 of my U.S. Patent 2,770,102). It will be understood that when ice is to be frozen water is led into the mold cavities in a manner also shown in my US. Patent 2,770,102 (see water line 13, FIG. 2 of that patent). After the ice has been frozen, a working fluid is pumped underneath the liners (see elements 21, .22, 46, 64 and 65 in FIGS. 3, 4 and 9 of my US. Patent 2,770,102) in order to invert the liners (see FIGS. 2 and 3 of the present patent application) and eject the ice masses.

The FIG. 1 embodiment has seven mold freezing cavities or compartments, each provided with a liner such as liner 47. In order to guide the frozen ice cubes into the tray there are mounted on top of the mold a plurality of deflecting

members

65, 66, 67, 68, 69, 70, 71 and 72, each being formed with concave deflecting surfaces. One such member is located on each side of each cavity.

Attention is now invited to the heater 45 (FIGS. 2, 3 and 4) which is provided in accordance with the invention. This heater is utilized and controlled, in a manner described below, to facilitate and expedite the ejection of the ice cubes.

Attention is further invited to the swingably mounted vanes 11-17 (FIG. 1) each of which carries an individual one of the mercury switches 1824 in such manner that when a liner, such as 47, is in the inverted position (FIG. 3) the liner swings the vane counterclockwise and closes the switch. For example, in FIG. 3 ice has been ejected and the switch 18 senses that fact, vane 11 being forced to its counterclockwise position by the inverted liner 47. Vane 1.1 is representative of the seven vanes and it is swingably mounted on a suitable pivot 75. When each liner, such as 47, returns to its water receiving position, the vane then drops to its clockwise position, as shown in FIG. 2. The function of all of these switches in the aggregate is to sense when ice has been ejected from all of the liners.

The discussion below will deal not only with the mercury switches or sensing devices 1824, but it will also discuss the basket switch 51, which is a mercury switch like in structure and broad function to that shown at 55 in FIG. 2 of my US. Patent 2,770,102. Arm '74 is secured to vane 14 and is therefore in raised position when the tray 73 is full of ice cubes. When in that position arm 74 opens switch 51. The switch 51 is shown in FIGS. 1 and 4 and corresponds to that numbered 55 in my said U.S. Patent 2,770,102.

Referring now specifically to FIG. 4, there is illustrated a preferred form of control system in accordance with the invention. The system will be described in terms of elements performing the various functions involved, using as a starting point the conditions present when water in all of the ice cavities has frozen. In order to sense the fact of such freezing and then automatically to initiate a series of events which cause the ice cubes to be ejected, there is provided a thermostat switch 36 (FIG. 4). This thermostat switch is open until water in the ice molds is frozen, whereupon the switch 36 closes.

The initiation of ejection is desired only when the ice cube basket is not full and therefore there is placed in series circuit with thermostat 36 a mercury switch 51. p

This switch 51 is open when the basket is full of cubes and it closes to sense that the basket is not full and to permit ejection to occur when it is ordered by the thermostat 36. Now it will be observed that switches 51 and 36 are in series circuit with one side 60 of an alternating current 'supply line and they are also in series circuit with coil 40 of a relay 35. Included in relay 35 is a holding circuit comprising contacts 37 and 38, which holding circuit is closed when coil 40 is energized.

Now in accordance with the invention, the ejection of the ice cubes is accomplished by a combination of hydraulic pressure under the liners which contain the cubes and heat, which facilitates their severance from the liners. It will therefore be understood that the harvesting relay 35 should initiate the performance of two functions: energizing of heater 45 and motor 43. Accordingly there are provided in that relay contacts 41 and 42 in series circuit between the ungrounded power supply line 63 and forward-run motor 43 which is coupled, via speed reducer 76 and drive coupling 77 to a hydraulic pump 44, thereby driving the pump in the forward-run direction. When the pump drives in that direction it withdraws hydraulic fluid, via line 78, from reservoir 55 and forces fluid under pressure through line 64 for the purpose of forcing the ice cubes out of the liners.

The contacts 41 and 42 are also in series circuit between electrical supply line 60 and heater 45 so that when the relay 35 is actuated, heater 45 is energized whereby, as indicated above, both heat and pressure are utilized to sever the ice cubes from the molds.

The discussion of the system at this point has assumed that an order to prepare cubes has been given at some place in the system. This order is rendered by a timer and programming device 30, which includes a circuit closing device comprising a cam 33 and a pair of contacts 34 in series circuit between the holding circuit of relay 35 and line 60. When cam 33 is closing the contacts 34 this action is effectively an order to eject ice cubes when they are ready, provided the conditions sensed by the full basket switch 51 and thermostat 36 so indicate.

At this point there has been described the structure which functions to supply pressure and heat to the liners for the purpose of ejecting the ice cubes.

Collaterally the hydraulic pump 44 is provided with a relief by-pass valve 46 which by-passes hydraulic fluid until the heat generated by heater 45 has become effective to release the ice cubes. When each flexible liner 47 yields to the pressure of the pump, as limited by the relief bypass, each ice cube is ejected and each mold assumes an inverted position, as illustrated in FIG. 3. Now, as was explained in the description of FIGS. 2 and 3, there is associated with each liner a swingably mounted vane, the vanes being numbered 11-17. Each vane carries one of the mercury switches 18-24. The mercury switches 18-24 are closed when the several vanes are elevated by the inverted liners. When all of the ice cubes have been ejected and all the liners have been inverted, then the switches 18-24, being in series circuit with each other and also with motor 50 of the timer-programmer, cause the motor to begin to run. That is, the switches sense that all cubes have been ejected and by closing they collectively tell the timer-programmer 30 that a new cycle can be initiated. That is, they tell the timer-programmer that all of the liners are empty. The timer-programmer motor 50 includes a holding circuit which comprises full revolution cam 31 and contacts 32, the latter being closed by the cam 31 to cause motor 50 to run sufficiently long to go through a full cycle of the timer-programmer.

At this point the description proceeds to the structure which causes the hydraulic fluid to be withdrawn from underneath the molds and put back into the reservoir 55. It will be understood that the functions called for at this point (i.e. ice ejected) are the stopping of motor 43 and reversal of pump 44 and deenergization of heater 45, and

' the performance of these functions in turn calls for the opening of relay 35. Accordingly, the timer-programmer 30 is so arranged that at this point in the cycle the forward-run cam 33 opens the contacts 34, interrupting the holding circuit of relay 35, and allowing the relay to open, thereby breaking the circuit to the forward-run motor 43 and also the circuit to the heater 45.

Now in order to drive the pump 44 in the reverse direction there is provided a reverse motor 52 which drives through speed reducer 76 and coupling 77 so that pump 44 withdraws hydraulic fluid through line 64 and forces it into reservoir 55 via hydraulic line 78. The motor 52 receives an order from the timer-programmer, being in series circuit with reversing contacts 58 which are closed by reversing cam 48. Because of the action of the holding circuit comprising the

elements

31 and 32, the motor 50 continues to run even after the energizing circuit comprising the switches 1824 is opened as the vanes 1117 return to their down positions.

Now at this point in the cycle the timer-programmer 30 is running and the liners are empty and the discussion therefore proceeds to the structure which again furnishes water to the liners. This structure consists of a water supply line 25 and a controlling solenoid 56 and a water line 27 leading to the ice liners. The solenoid 56 is energized when the cam 53 closes contacts 54 (if contacts 58 are closed), this constituting an order to fill the molds with water.

Referring now to the timer-programmer, it will be understood that when all switches 18-24 become closed there is automatically given to motor 50 of timer-programmer 30 an order to start and that motor in turn actuates

elements

31 and 32 to give itself an order to hold, Whereupon, in sequence, the timer-programmer functions as follows:

elements

33 and 34 to deenergize relay 35 and therefore to break the circuits of forward motor 43 and heater 45, the

elements

48 and 58 to make the circuit of motor 52 and therefore to cause the hydraulic fluid to be withdrawn from under the liners; cam 53 and contacts 54 to energize solenoid 56 and cause the liners to be suitably filled with water.

Having described the arrangement and the control system I shall now describe a cycle of operation.

When water in the ice mold 39, FIG. 1, becomes frozen the thermostat switch 36 closes. The closing of the thermostat switch sends current through to the full basket detector arm mercury switch 51 to the relay coil 40 of the relay 35 which closes, making holding contact on itself through the circuit of its terminals 37 and 38, which circuit is in series with the forward-run contactor 34 of the timer-programmer 30.

At the time the relay 35 closes contacts 41 and 42 of the relay close the circuit on the forward-run motor 43 of the hydaulic pump 44 and on the heater circuit of heater 45, FIG. 4. Contacts 41 and 42 of the relay are ejectionordering means. The heater 45 is clamped to the ice mold 39, as shown in the description of FIG. 1.

The hydraulic pump 44 is provided with a relief bypass valve 46 and by-passes hydraulic fluid until the heat has become effective in releasing the ice pieces. When the flexible liners such as 47, FIGS. 2 and 3, yield tothe pressure of the pump as limited by the relief by-pass, the ice pieces are ejected and the flexible liners assume an inverted position, FIG. 3, holding the vanes 1117 carrying the mercury switches 18-24 in an up position. In the up position the mercury switches 18-24 are closed. The mercury switches are connected in series and when all the mercury switches are up and closed the circuit is, as a result, closed on the motor 50 of the timer-programmer 30.

The timer-programmer 30 upon starting makes contact upon itself through the full revolution cam 31 and contacts 32 and does not again stop until a full cycle of the timer-programmer 30 has been made.

As the timer-programmer 30 continues to run the forward-run cam 33 opens contacts 34 and the hold circuit of the relay 35 is interrupted, allowing the relay to open. The opening of the relay breaks the circuits to the forward-run motor 43 of the hydraulic pump 44 and to the heater 45. Still further running of the timer-programmer 30 closes contacts 58, completing a circuit to the reverse motor 52 of the hydraulic pump 44 and to the water fill contacts 54 of the timer-programmer 30. As the reverse motor 52 runs, hydraulic fluid is pumped from beneath the inverted flexible liners such as 47, FIG. 3, back to the reservoir 55, and the flexible liners are restored to the fill position, FIG. 2, by atmospheric pressure.

As the flexible liners resume the down or water fill position as shown in FIG. 2, the vanes 11-17 carrying the mercury switches 18-24 also return to a down position and the mercury switches open the circuit they have previously made on the timer-programmer motor 5t but this motor continues to run because there is another circuit still supplying it with current through the holding or complete-cycle cam 31 and contacts 32.

As the reverse motor 52 runs pumping hydraulic fluid back to the reservoir 55 the water fill cam 53 and contacts 54 of the timer-programmer make contact, causing the solenoid water valve 56 to open and admit water to the freezing molds 47. Since the reverse run contacts 58 of the timer-programmer 30 are used to bring current to the water fill contacts 54 and the water fill contacts 54 is thus in series with the reverse run contacts, the breaking of the circuit of the reverse run contacts also breaks the water fill circuit to the water fill solenoid valve 56. By the combined action of the two sets of cams 48 and 53 and contacts (the reverse run and the water fill) a brief time period of in the neighborhood of fifteen seconds can be obtained for the duration of the water fill even though the timer-programmer 30 is slow running, such as one revolution in five or six minutes. The slow speed of the timer would make it diflicult to obtain a close coupled on and o action from a single cam.

As described so far the liners are now back in the ice freezing position, are filled with water, and the timerprogrammer is running on to reach its automatically off position by the action of the one revolution or full cycle cam 31 and contacts 32.

In the operation described the thermostat switch 36 became reset to open it contacts at a point in time after heat was applied by the heater 45, both the heater and the thermostat 36 being clamped to the ice mold 39.

When the thermostat switch 36 opens due to heat application, the relay 35 which it has caused to close does not open because of the use of its self holding contacts 37 and 38, maintaining the circuit on the coil 40 of the relay in series with the forward run contacts 34 of the timer-programmer.

When the timer-progammer reaches its automatic stop position all current is off until the thermostat switch 36 again closes, indicating that ice pieces are again ready for harvest.

Thus it will be seen that the improvement in accordance with the invention comprises, in combination: a plurality of switching means 18-24 individual to the several cavities for sensing that all of the frozen ice cubes have been ejected from the cavities; and a timer-programmer 30 including a motor 50. The switches 1824 are included in circuit between the motor 50 and the energy source (i.e. supply line 60) in order to prevent the motor from starting unless all of the switches 1824 are closed to indicate that the cavities are empty. The timer-programmer further includes

means

31, 32 for assuring that the motor runs through a predetermined cycle. The timer-programmer 30 further includes means 53, 54 for controlling the water supply means 56, 27 so that water is delivered to the ice cavities. Additionally, the timerprogrammer 30 includes

means

48, 58 for controlling the element 52 of the reversible pumping means 43, 52, 76, 77, 44 to force the working fluid back into the reservoir 55. Finally there is included in the timer-programmer 30 a first circuit closing means 33, 34, which is provided simply to assure that the ejection-control relay or harvesting 35 will not become activated unless an order for programming has been made. The first circuit closing means 33, 34 is therefore a harvest-enabling means.

The thermostat 36 is the means for sensing that the water in the cavities has become frozen and the element 51 is the means for sensing that the tray is not full. The

combination further includes the relay means 35 which is controlled by the sensing means 36 and 51, on condition that the water has frozen and the tray is not full and the circuit closing means 33, 34 is closed, to initiate the ejection function. Accordingly the combination includes a heater 45 and second circuit closing means 41, 42 between the energy source and the heater 45, as well as the forward element 43 of the reversible pumping means, this second circuit closing means being actuated by the relay 35 to cause the reversible pumping means to pump working fluid under the cavities, so that the ejection function is performed by the application of both heat and pressure.

While there has been shown and described what is at present considered to be the preferred embodiment of the present invention, various modifications and changes will occur to those skilled in the art, and it is intended in the appended claims to secure the invention with a proper range of equivalents.

Having described my invention, 1 claim:

1. In an automatic ice maker of the type including a plurality of mold cavities, flexible liners secured within each of said cavities, means for supplying water to said liners when the liners are disposed within the mold cavities, means for supplying a refrigerated environment for freezing said water, a reservoir for working fluid, and reversible pumping means for withdrawing working fluid from the reservoir and forcing it beneath said liners whereby the liners are flexed to eject ice formed therein, and a tray for frozen ice, the improvement which comprises in combination: a plurality of switching means individual to the several cavities for sensing that all of the frozen masses of ice have been ejected from said cavities; a timer-programmer including a motor, said switches being included in circuit between said motor and an energy source in order to prevent. the motor from starting unless all of the switches are closed to indicate that said cavities are empty; said timer-programmer further including means for assuring that the motor runs through a predetermined cycle, means controlling the water supply means so that water is delivered to the ice cavities, means for controlling the reversible pumping means to force the working fluid back into the reservoir, and a first circuit closing means; means for sensing that the water in the cavities has become frozen, means for sensing that the tray is not full, relay means controlled by the last two sensing means, on condition that the water has frozen and that the tray is not full. and that the first circuit closing means is closed, to initiate the ejection function; a heater for melting ice, and a second circuit closing means between said energy source and the reversible pump means and actuated by said relay means to energize the heater and to cause the reversible pump means to pump working fluid under said cavities, whereby the ejection function is performed by the application of both heat and pressure.

2. In an automatic ice maker of the type including a mold including several cavities, means for supplying water to said cavities, and means for supplying a refrigerated environment for freezing said water, the improvement which comprises in combination: an ice heater, pressure means activated to eject ice from the mold and relieved to ready itself for reactivation, relay means for activating the pressure means and the heater, a timer-programmer comprising: first, a motor; second, first contact means for controlling the pressure means so that it is relieved; third,

second contact means dependent on the first contact means for controlling the water supply means to deliver water to the mold; and fourth, a third contact means, said relay means being responsive to the third contact means for initiating the ejection function, whereby the ejection function is performed by the application of both heat and pressure, and a plurality of switching means individual to the several cavities for sensing that all of the frozen masses of ice have been ejected from said cavities; said switching means being included in circuit between said motor and its energy source in order to prevent the motor from starting unless all of the switches are closed to indicate that said cavities are empty.

3. The combination in accordance with claim 2 in which the motor has fourth contact means for assuring that the motor will remain energized for a predetermined cycle and in which all the contact means are activated by ganged rotary cams.

4. In an automatic ice maker of the type including a plurality of mold cavities, individual flexible liners secured within said cavities, means for supplying water to said liners when the liners are non-inverted and disposed within the mold cavities, means for supplying a refrigerated environment for freezing said water, a reservoir for working fluid, reversible pumping means for withdrawing working fluid from or returning it to the reservoir, and a heater for melting the ice to aid in the ejection, the improvement which comprises in combination:

a thermostat having an open condition and a closed condition for indicating the presence of ice in the molds,

a harvesting relay in circuit with said thermostat and adapted to be energized when the thermostat is in closed condition, said relay including a relay holding circuit,

a programming device comprising a motor having a motor holding circuit and a plural-circuit cam switch driven by said motor, said cam switch including 8 harvest-enabling means in series with said relay holding circuit, said relay further including ejection-ordering means adapted to cause the reversible pumping means to withdraw fluid from the reservoir and force it beneath said liners, whereby the liners are inverted and eject the ice, and to energize the heater whereby the ejection is aided,

means sensitive to the absence of ice in the molds for starting said timer motor, said plural circuit cam- 10 switch further including the following contact means,

means for closing the motor holding circuit,

means for causing the reversible pumping means to return working fluid to the reservoir whereby the liners are restored to their normal positions,

and means for controlling the water supply means to supply water to said molds. 5. The combination in accordance with claim 4 in which the automatic ice maker includes a tray for frozen ice and in which the improvement includes an overfill switch adapted to be closed when the tray is not full, said switch being in series with said harvesting relay and said thermostat whereby the thermostat cannot be energized unless the tray is not full.

ROBERT A. OLEARY, Primary Examiner.

W. E. WAYNER, Assistant Examiner.

Claims

4. IN AN AUTOMATIC ICE MAKER OF THE TYPE INCLUDING A PLURALITY OF MOLD CAVITIES, INDIVIDUAL FLEXIBLE LINERS SECURED WITHIN SAID CAVITIES, MEANS FOR SUPPLYING WATER TO SAID LINERS WHEN THE LINERS ARE NON-INVERTED AND DISPOSED WITHIN THE MOLD CAVITIES, MEANS FOR SUPPLYING A REFRIGERATED ENVIROMENT FOR FREEZING SAID WATER, A RESERVOIR FOR WORKING FLUID, REVERSIBLE PUMPING MEANS FOR WITHDRAWING WORKING FLUID FROM OR RETURNING IT TO THE RESERVOIR, AND A HEATER FOR MELTING THE ICE TO AID IN THE EJECTION, THE IMPROVEMENT WHICH COMPRISES A COMBINATION: A THERMOSTAT HAVING AN OPEN CONDITION AND A CLOSED CONDITION FOR INDICATING THE PRESENCE OF ICE IN THE MOLDS, A HARVESTING RELAY IN CIRCUIT WITH SAID THERMOSTAT AND ADAPTED TO BE ENERGIZED WHEN THE THERMOSTAT IS IN CLOSED CONDITION, SAID RELAY INCLUDING A RELAY HOLDING CIRCUIT, A PROGRAMMING DEVICE COMPRISING A MOTOR HAVING A MOTOR HOLDING CIRCUIT AND A APLURAL-CIRCUIT CAM SWITCH DRIVEN BY SAID MOTOR, SAID CAM SWITCH INCLUDING HARVEST-ENABLING MEANS IN SERIES WITH SAID RELAY HOLDING CIRCUIT, SAID RELAY FURTHER INCLUDING EJECTION-ORDERING MEANS ADAPTED TO CAUSE THE REVERSIBLE PUMPING MEANS TO WITHDRAW FLUID FROM THE RESERVOIR FORCE IT BENEATH SAID LINERS, WHEREBY THE LINERS ARE INVERTED AND EJECT THE ICE, AND TO ENERGIZE THE HEATER WHEREBY THE EJECTION IS AIDED, MEANS SENSITIVE TO THE ABSCENCE OF ICE IN THE MOLDS FOR STARTING SAID TIMER MOTOR, SAID PLURAL CIRCUIT CAMSWITCH FURTHER INCLUDING THE FOLLOWING CONTACT MEANS, MEANS FOR CLOSING THE MOTOR HOLDING CIRCUIT, MEANS FOR CAUSING THE REVERSIBLE PUMPING MEANS TO RETURN WORKING FLUID TO THE RESERVOIR WHEREBY THE LINERS ARE RESTORED TO THEIR NORMAL POSITIONS AND MEANS FOR CONTROLLING THE WATER SUPPLY MEANS TO SUPPLY WATER TO SAID MOLDS.