US1824774A - Circuit control mechanism for mechanical refrigerating apparatus - Google Patents

Description

Sept. 29, 1931. F. R. ERBACH 1,824,774

CIRCUIT CONTROL MECHANISM FOR MECHANICAL REFRIGERATING APPARATUS Filed Dec. 19, 1927 1:: \fvw v INVENTOR. Eedez'ickEErbdch A TTORNE Y5.

Patented $6 ,029, 1931- UNITED STATES (PATENT OFFICE.

FREDERICK R. war or DETROIT, MICHIGAN, ASSIGNOR To KEtvINAToR conno- RATION, OF DETROIT, MICHIGAN,

A CORPORATION OF MICHIGAN CIRCUIT CONTROL MECHANISM FOR MECHANICAL REFRIGEBATING APPARATUS Application filed December 19, 1927. Serial No. 241,072.

Mechanical refrigerating apparatus now associated with refrigerators operate periodically to automatically "maintain a predeter- -mined range of temperature by means of a 5 temperature responsive mechanism which makes and breaks the electrical circuit leading from a source of electrical supply tothe motor for driving a compressor. A cooling unit is arranged in communication with the chamber to becooled and compartments for receiving trays containing liquids to be frozenare usually arranged interiorly of the cooling unit. With such intermittently operating apparatus, a considerable time is re- 1 quired to freeze the liquids in the trays when thetemper ature range maintained in the refrigerator is above freezing, and under some circumstances it is desirable to procure quicker freezing than that resulting from apparas tus set to automatically maintain a temperature range above freezing.

An object of my invention is to procure continuous operation of automatically actuated mechanical refrigerating apparatus, normally operating intermittently, in order to decrease the time for freezing liquidswithin a refrigerator.

Afurther object of my invention is to asso-- ciate mechanism with automatic mechanical 3o. refrigerating apparatus, normally operating intermittently, which can be manually moved into a position to cause continuousoperation of the refrigerating apparatus,-and which is automatically returned to its original position when a predetermined temperature is effected in therefrigerator by the continuous operationof the apparatus.

Another object of my invention is to utilize an air circulation control damper in a refrigerator for effecting operation of a switch mechanism associated in the electri'calcircuit extending from a source of electrical supply to a driving motor. T I

' Other objects of my invention moraor less incidental orancillary to the foregoing will appear in the followingdescription which" sets forth, in connection with the drawings I accompanying and forming a. part of this specification, a preferred embodiment of the. invention. s D

I R-EISSUED n the accompanying rawings Figure 1 is a front elevation of a refrigerator cabinet having a mechanical cooling unit in-one compartment and my control device associated with a flue therein through which the air circulates, the doors of the cabinet being removed; and

Figure 2 is an elevational view of my inve'nt1on, partially diagrammatic, associated with the adjacent portion of the refrigerator cabinet, which is shown in section.

Referring now to the drawings by characters of reference, 10 illustrates a refrigerator cabinethaving an interior chamber .divided by vertical partition 11 anda horizon.- tal partition-l2 providing food storage chambers 13' and 14 and a chamber 15 for the reception of the heat transfer unit 16 of mechanical refrigerating apparatus. The mechanical refrigerating apparatus can be of the compressor-condenser-evaporator type having an electrical circuit 17 extending through a motor 18 which operates the compressor (not shown), the circuit being automatically broken and established by a thermostatically actuated switch mechanism 18. The partition 12 is provided with a flue 19 and the partition 11 is provided with upper and lower flues 20 and 21. the flues allowing a circula- I tion of air through the chambers. The structure so far described is so generally known and, understood that a more complete disclosure and further description of the details is not thought to be necessary to understand my invention which is associated therewith, and which Iiwill now describe.

The automatic control of refrigerating apparatus, in maintaining a redetermined temperature range above freezing in the food storage compartments, will start and stop several times before water or fluids will be frozen after insertion into the open chambers in the cooling unit, and therefore an objectionable length of time is required for the freezing operation. In order to decrease the freezing time normally required by automatically operated mechanical refrigerating apparatus, I have provided mechanism for causing the refrigeratingi'apparatus to operate continuously until a predetermined low temperature V a bracket 2&rvlhi m s ttachl illql depending.

is obtained in the cooling chamber which mechanism is arranged to be associated with an air circulation control damper 22. This mechanism is arranged in a circuit parallel to that of the thermostat 18 and consequently is not affected by the operation of that element. A reinforcing collar 23 is secured to the partition 12 adjacent the flue opening 19 therein, and such member is provided with a bearing portion 24 and a surrounding opening which permits air to circulate from the chamber 15 to the chamber 14., The damper 22 is preferably arranged within the chamber 15 and is of such size that it can close the open ing in the member 23 to shut off air circulation between the chambers 15 and 14. The damper is provided with a stem portion 25 which extends through the bearing 24 and into the chamber 14, the stem terminating in a hand-leportion 26. A coil spring 27 surrounds the stem portion of the'damper structure intermediate the closure member 22 and the bearing member 24. Such spring normally maintains the closure member in open position with respect to the fiue19.

A motor control device is arranged to be.

actuated byv the movement of the damper, and the mechanical portion thereof is carried by portion 29 of the member 23. A switch base i 30, formed of insulating material, is secured from in spaced and parallel relation toward the stem portion 25 of the damper. The damper stem is provided with a projecting portion 33 which is arranged to engage and actuate the upper contact arm and move it into engagement with the lower contact'arm When the damper is pulled downwardly to close the flue opening 19. It will thus be seen that when the damper is moved to closed position, the top switch arm 32 will be forced thereby into engagement with the other switch arm, thus establishing an electrical circuit through the motor 18 which will cause continuousoperation ofv the refrigerating apparatus until such time as the damper is L movedto open position.

i the upper end of the lever 36 when the damper ismoved to closed position. The lever is The damper stem is provided with a notch 34 which is engaged by a pawl35 formed at pivoted adjacent its lower end between the bracket extensions 37, and coil springs 38 and 39 extend betweenand are secured to the ends of the lever 36 and the bracket 28, the ends of the springs extending through the bracket 28 and being threaded to receive securing nuts 40. The relative tension of the springs 38 and 39 and the mounting of the lever 36 is such that the pawl 35 will automatically move into the notch 34 when the notch is moved to a position opposite the pawl, in which position the damper Will be in a position to close the flue opening 19. It will be seen that the stem portion of the damper extends into the chamber 14, so that the handle portion 26 can bereadily grasped when the refrigerator door is open in order to move the damper downwardly into a position in which it will close the flue opening in the partition 12. When the damper is manually moved to closed position, the pawl 35 engages the notch 34 in the damper stem and automatically maintains the damper in closed position until released. A thermostat device is associated with the lever 36 f0r releasing the pawl from the notch in the damper arm when a predetermined low temperature has been reached within the chamber-15.- This device consists of a bellows member 41 which is closed at one end and engages with an extension of the lever 36. The bellows is secured to'the bracket 28 and a condu it 42 communicating leads from the bellows ll dth housing 43. T Itwillb e understood tha a suitable expansible fluid is placed Within the bellows-and the communicating conduit 42 and housing 43 which will be affected by the temperature in the chamber 15 causing the bellows 41 to contract and expand, so that when a predetermined freezing temperature hasbeen reached in the chamber 15, the movement ofthe bellows toward the bracket 28 moving the lever 36 therewith releases the pawl 35 from the notch 34 in the damper stem allowing the switch arms to separate as the damperstem is moved by the spring 27 to open position.

It will be understood that when a freezing temperature is produced in the chamber 15 and the air is permitted to circulate, then food stored within the chambers 13 and 14 will befrozen and spoiled. By arranging the damper so that it cooperates with the circuitcontrol mechanism, it will be seen that the damper will be closed when the circuit is established to produce a lower temperature in the compartment than is permitted when under the control of thermostat 18, and in this manner circulation of'air when the lower temperature for freezing is'desired will be prevented. Under such circumstances there will be very little likelihood of the air within the, food storage chambers becoming cold enough to freeze and spoil the food stored therein. -The thermostat bellows can be adjusted to release the pawl so that the desired temperature in the chamber 15 can be obtained by the relative adjustment of the tension of the springs 39.

Although I have illustrated but one form of my invention and have described in detail but a single application thereof, it will be apparent to those skilled in the art that it is not so limited but that various modifications and changes may be made therein without departing from the spirit of my invention or the scope of the appended claims.

What I claim is:

1. In combination with refrigerating apparatus having electrical connections for establishing a circuit between a driving motor and a source of electrical supply, an automatically operated switch mechanism for establishing and breaking said circuit upon predetermined temperature conditions, and a second switch mechanism for controlling said circuit independently of said automatically operated switch mechanism, said last mentioned switch mechanism being manually operable -to establish said circuit and including means for automatically breaking said circuit under a predetermined temperature condition.

2. In combination with refrigerating apparatus having electrical connections for establishing a circuit between a driving motor and a source of electrical supply, an automatically operated switch mechanism for establishing and breaking said circuit upon predetermined temperature conditions, a manually operable mechanism for establishing said circuit independently of said switch mechanism, and automatic means for breaking the circuit established by said manually operable means. Y

3. In combination with refrigerating apparatus having electrical connections for establishing a circuit between a driving motor and a source. of electrical supply, automatically operated switch mechanism responsive to close and break said circuit upon predetermined temperature conditions, and a second switch mechanism adapted to close and break said circuit independently of said first switch mechanism, said secondswitch being manually operable to close the circuit and automatically operated to break the circuit upon a lower temperature than eflected by said first mentioned switch mechanism.

4. Control mechanism for an electrical circuit associated with refrigerating apparatus, comprising in combination a switch mechanism in said circuit, an air circulation control damper for causing actuation of said switch mechanism to make and break said comprising the combination of a switch, an air clrculation damper arranged to actuate said switch, said damper being manually op between the compartments, of means for preventing such circulation of air and for initiating the operation of the condensing unit simultaneously, and means for rendering the last mentioned means inoperative when the temperature of the freezing compartment reaches a predetermined sub-normal value.

In testimony whereofI hereunto aflix my signature.

FREDERICK R. ERBACH.

circuit, said damper being manually actuated to prevent air circulation and to move said switch to close said circuit, said damper being-automatically moved to permit air circulationand to permit said switch to move position, and a thermostat connected to allow automatic movement of said damper.

5. Control mechanism for an electrical circuit associated with refrigerating apparatus

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