US2094719A

US2094719A - Refrigerating apparatus

Info

Publication number: US2094719A
Application number: US700273A
Authority: US
Inventors: Lawrence A Philipp
Original assignee: Kelvinator Inc
Current assignee: Kelvinator Inc
Priority date: 1933-11-29
Filing date: 1933-11-29
Publication date: 1937-10-05
Anticipated expiration: 1954-10-05

Description

Oct. 5, @37 l.. A. PHILIPP 2,094,719

REFRIGERAT ING APPARATUS Filed NOV. 29, 1955 IVENTOR. ww/wz @L 1MP? Patented oct. s, 1937 UNITED STATES PATENT OFFICE REFRIGERATING APPARATUS poration of Michigan Application November 29, 1933, Serial No. 700,273

8 Claims.

The present invention relates to refrigerating systems and particularly a refrigerating system in which the cooling element is maintained normally at a predetermined temperature and in which the cooling element is rendered temporarily more effective for hastening refrigeration.

One of the objects of the present invention is to provide an improved refrigerating system in which the cooling element is rendered more effective automatically in response to a demand for quick refrigeration.

In furtherance of this object, it is another object of the present invention to restore the refrigerating system to its normal operation after 1thei demand for hastened refrigeration is satis- A further object of the invention is to provide a refrigerating system in which a controller 20 thereof operates to maintain the cooling element normally at a desired temperature and, in which a separate thermostat, which is responsive to a commodity to be cooled, operates to modify temporarily the characteristics of the controller so that the controller operates to cauce the cooling element to hasten its refrigerating eiect on the commodity.

Further objects and advantages will be apparent from the following description, reference being had to the accompanying drawing wherein a preferred form of embodiment of the present invention is clearly shown.

In the drawing:

Figfl is a diagrammatic View of my improved refrigerating system, and

Fig. 2- is a front view of a refrigerator to which my improved system is particularly applicable.

For the purpose of illustrating one use of the improved refrigerating system, there is shown, in 40 Fig. 2, an insulated refrigerator cabinet 20 of the household type having a storage compartment 2| below which there is disposed a machine compartment, the door of the latter compartment being indicated at 22. The door 23 of the storage or heat absorbing means, herein shown as comprising an evaporator 25, is disposed within the storage compartment and the heat dissipating element, herein shown as comprising a compressor 26, a condenser 21 and a motor 28, are disposed within the machine compartment.

The evaporator 25 is formed of a plurality of concentric sheets of metal joined at intervals and also a lower inlet header 30 and an upper outlet header 3|. Vaporized refrigerant which is compartment is shown open. A cooling element (Cl. (S2-4) withdrawn from the upper header 3| by the compressor through a suction pipe 32, is compressed and forced into the condenser 21 by the compressor. The refrigerant is condensed in the condenser 21 and passes ,'by way of pipe 35 to the 5 receivingchamber 36 of a high-side-float type expansion valve 31. The outlet valve 38 of eX- pansion valve 31 is controlled by a float` 39 which `rises to permit the escape of refrigerant when a certain quantity of liquid refrigerant collects in chamber 36. From chamber 36, the refrigerant flows through pipe 4| to the lower header 38 of evaporator 25.

'I'he motor 28 drives the compressor 26 through a belt 4S and the circuit to the motor is controlled by a switch 44. The circuit to the motor 28 includes a Wire 45, a stationary contact 46, a movable contact 41, a stationary contact 46, a wire 49, the motor 28 and a wire 50.

The temperature within the storage compartment 2l is of course responsive to the temperature of the evaporator 25 and for the purpose of maintaining a desired temperature, I have for illustrative purposes, disclosed a system in which the temperature of the evaporator is governed by controlling the duration of operation of the co1.;- pressor 26, and the switch 44 is utilized for starting and stopping the compressor motor 28.

Switch 44, which is diagrammatically shown for the sake of clearness, comprises a frame 52 having platforms 53 and 54 which support metallic bellows 55 and 56 respectively. Two main levers 51 and 58 are pivotally mounted at 59 and 60 and are arranged to be moved upwardly by bellows 55 and 56 respectively. A coil spring 62 is in.- terposed between the topy of lever 51 and a movable abutment 63. This abutment 63 is screw threaded into a top platform 64 of frame 52 and can be turned by hand for adjusting the tension of spring 62. Lever 51 includes an upright arm 66 which arm provides bearings for knife edge end portions on levers 61 and 68 of a snap acting mechanism. Stops 10 and 1| limit the upward movement of levers 61 and 68, and a stop 'I2 limits the downward movement of lever 61. Lever 45 68 carries the movable contact 41 and the en gagement of this contact with contacts 46 and 48 limits the downward movement of lever 68. A coil spring 14 is connected between levers 61 and 6B and normally tends to hold the levers in the 50 position shown in which contact 41 bridges contacts 46 and 48 or in 'a position in which the levers engage stops 10 and 1| in which latter position, the contacts are separated.

'I'he platform 53 of frame 52 provides an up- 55 tends to hold the levers against either the lowerv or upper stops. A coil spring 86 is connected with the end of lever 58 and a bolt 81 and the bolt can be adjustably set to govern the tension of spring 86. Bellows 55 is connected by a. tube 89 with a bulb 90 and this system contains a volatile fluid which expands and contracts with increase and decrease in temperature. Bellows 56 is connected by a tube 9| with a bulb 92 and this system also contains a volatile fluid.

'Ihe adjustment of the spring 86 is such that during normal operation, bellows 56 is retracted and the end of rod 16 is below the path of movement of lever 51 and is therefore ineffective. The compressor 26 being operative, it will cause a decreasing in temperature of the evaporator 25 and when the temperature is lowered to the desired minimum, pressure within the bulb 98, tube 89 and bellows 55 will be decreased sufficient to cause the knife edge bearings of upright 66 to be lowered to below its dead center position with respect to levers 61 and 68 and the spring 14 will snap the switch open to thereby separate contact 41 from 46 and 48 and thus break the motor circuit. The evaporator will then gradually increase in temperature and when the temperature attains a predetermined high value, the pressure in bellows 55 will cause the bellows to move the upright to snap the contacts closed.

The spring 62 is adjusted so that the system operates to maintain the desired mean temperature in the storage compartment 2| of cabinet 28. Under this condition, water or the like, will gradually freeze within the evaporator 25. For this purpose shelves 94 are disposed in the evaporator 25 for carrying ice trays or the like 95. At times it is desirable to hasten refrigeration for example when it is desirable to quickly freeze water or congeal a. dessert. In that event, the commodity to be refrigerated is placed on the shelf to which the bulb 92 is bonded. The heat from the commodity will cause an immediate rise in temperature and pressure of the uid within bulb 92 and consequently the bellows 56 will expand sufllciently to snap the rod 16 to the position shown in the drawing. If the electrical snap switch is not already closed, rod 16 will cause the closing of the same. Thus it will be understood that the rod 16 will resist the movement of the switch toward contact opening position and therefore cause a prolonged operation of the compressor and a lowering of the temperature of the evaporator below normal. The tension of the

springs

85 and 86 may be such that the pressure Within bellows 56 must recede to a pressure substantially equal to the congealng temperature of the commodity so that the resistance of rod 16 is not overcome and the compressor will continue to operate until the commodity is congealed. After the pressure in bellows 56 recedes to its predetermined minimum, the lever 51 will move the'rod 16 beyond its dead center position whereby said rod will no longer bel effective and the system is then automatically restored to the normal control of thermostat bulb 90.

It is apparent from the foregoing that I have the system to its normal operation after the demand for quick refrigeration has been satisfied.

While the form of embodiment of the present.

invention as herein described constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

I claim:

l. A refrigerating system comprising in combination a cooling unit, means for circulating a refrigerating medium through said unit, cyclical control apparatus including a thermo-bulb associated with said cooling unit for normally controlling the iiow of said medium, a thermostat arranged to be responsive primarily to the ytemperature of commodity placed in said cooling unit, and means actuated by said thermostat when the thermostat responds primarily to the temperature of-the commodity in said cooling unit for temporarily modifying ythe operation of said control apparatus.

2. A refrigerating system comprising in combination a cooling unit, means for circulating a refrigerating medium through said unit, cyclical control apparatus including a thermo-bulb associated with said cooling unit for normally controlling the ow of said medium, a thermostat arranged to be responsive primarily to the temperature of commodity placed vin said cooling unit, and means actuated by said thermostat when the thermostat responds primarily to the temperature of the commodity in said cooling unit for temporarily modifying the operation of said control apparatus, said last means including means operated automatically after a predetermined modiiied operation of said control apparatus for restoring the system to the normal control of said control apparatus.

3. A refrigerating system comprising in combination a cooling unit, having a tray supporting shelf therein, means for circulating a refrigerating medium through said unit, control apparatus including a thermo-bulb associated with said cooling unit for normally controlling the flow of said medium, and thermostatic means in immediate thermal association with said shelf for temporarily modifying the operation of said control apparatus in response to temperature of commodity placed on said shelf.

4. A refrigerating system comprising in combination a cooling unit, having a tray supporting shelf therein, means for circulating a refrigerating medium through said unit, control apparatus includinga thermo-bulb associated with said cooling unit for normally controlling the i'loW of said medium, and thermostatic means in immediate thermal association with said shelf for temporarily modifying the operation of said control apparatus in response to temperature of commodity placed on said shelf, said last means including means operated automatically after a predetermined modified operation of said control apparatus for restoring the system to the normal control of said control apparatus.

5. A refrigerating system comprising in combination a cooling unit, means for circulating a refrlgerating medium through said unit, motive means for driving said rst mentioned means, control apparatus including a thermo-bulb asamat/ie 3 sociated with said cooling unit to intermittently energize and deenergize said motive means for circulating said medium to maintain a normal temperature range, a thermostat arranged to be 5 responsive primarily to the temperature of material placed in said cooling unit, and means actuated by said thermostat for temporarily modifying the operation of said control apparatus.

6. A refrigerating system comprising in combination a cooling unit, means for circulating a refrigerating medium through said unit, motive means for driving said first mentioned means, control apparatus including a thermo-bulb associated With said cooling unit to intermittently energize and deenergize said motive means for circulating said medium to maintain a normal temperature range, a thermostat arranged to be responsive primarily to the temperature of material placed in said cooling unit, and means actuated by said thermostat for temporarily modifying the operation of said control apparatus, said last means including means operated automatically after a predetermined modified operation of said control apparatus for restoring the system to the normal control of said control apparatus. l

'7. A refrigerating system comprising in combination an evaporator having a tray supporting shelf therein, a compressor for withdrawing refrigerant vapor from said evaporator, condensing the same and returning liquefied refrigerant thereto, an electric motor for driving the refrigerant compressor, a switch for energizing or deenergizing said motor, a thermostatic switch actuating means including a thermo-bulb associated with said cooling unit for moving said switch to circuit making or breaking position to operate said compressor for maintaining a normal range of temperatures in said evaporator, modifying means associated with said thermostatic switch actuating means in normally disengaged relation thereto, and additional thermostatio means in immediate thermal association With said shelf for moving said modifying means to engaging position for temporarily modifying the normal operation of said switch in respense to the temperature of the commodity placed on said shelf, said last means including means operated automatically after a predetermined modied operation of said control apparatus for restoring the system to the normal controlof said control apparatus.

8. A refrigerating system comprising in combination, a cooling unit, means for circulating a refrigerating medium through said unit, a control element for said circulating means, a snap acting mechanism for moving said control element to either one of two extreme positions,

means for applying a varying pressure to actuate said snap acting mechanism in accordance with a predetermined condition, means for modifying the operation of said rst snap actingy mechanism comprising a second snap acting mechanism disposed in normally disengaged relation adjacent thereto, and thermal means for actuating said second snap acting mechanism to engaging position for causing one abnormal operation of said control element.

LAWRENCE A. PHILIPP.