US2198508A - Refrigerator - Google Patents

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US2198508A
US2198508A US86689A US8668936A US2198508A US 2198508 A US2198508 A US 2198508A US 86689 A US86689 A US 86689A US 8668936 A US8668936 A US 8668936A US 2198508 A US2198508 A US 2198508A
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evaporator
pump
electromotor
condenser
refrigerator
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US86689A
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Thomas Gustav
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00Arrangement or mounting of control or safety devices
    • F25B49/02Arrangement or mounting of control or safety devices for compression type machines, plants or systems

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  • the present invention relates to a refrigerator, the cooling system of which comprises a piston pump, an electromotor, a condenser, a heat exchange vessel and an evaporator.
  • the individual parts of the cooling system were mounted independent of each other in the casing, and when the arrangement is to be repaired or controlled the entire refrigerator must be taken apart. This is a serious drawback, since this disassembling of the parts requires much time and consequently involves high costs of repair. On the other hand the costs of manufacture are also high, since the individual mountingof the parts is a complicated task. The evaporator must be mounted subsequently to the other parts and that is another drawback.
  • the main object of -this invention is to remove these disadvantages. All parts of the cooling system are mounted together on a suitable formed and removable bottom of the piston pump casing. This bottom serves at the same time as an insulated cover plate for the cooling chamber.
  • bottom of the pump casing is preferably cast or stamped from a corrosion-proof and acid-proof light metal alloy or from other metals.
  • This construction of the refrigerator renders it possible to assemble all parts of the cooling system outside of the refrigerator casing and to insert the assembled structure into the casing by means of simple manipulations. When the cooling system is to be repaired or adjusted it may be removed from thecasing by reversing the simple operation just described.
  • This arrangement also involves the advantage, that the cooling system can be moved, e. g., transported to a testing room without the bulky casing. The cooling system is not mounted in the refrigerator casing until it has been tested.
  • the bottom of the pump casing is preferably arranged to serve as a heat insulating plate.
  • the bottom member is preferably cast or stamped with clearances or raised portions, for instance right below the pump casing, thus providing an additional insulation, consisting of a layer of air.
  • the refrigerator is also equipped with. an automatic switch, which opens the motor circuit, when the transmission of power from the motor to the compressor is disturbed.
  • an automatic switch which opens the motor circuit, when the transmission of power from the motor to the compressor is disturbed.
  • the motor is preferably tiltably arranged on the bottom or base plate of the pump casing in such a manner, that under the influence of a spring or its own weight or by some other expedient it will tilt out of its normal position and 5 actuate the switch, when the tension of the belt is reduced. It is also possible to arrange a belt stretcher in such a manner, that it will actuate the switch when the driving belt slides off the pulleys.
  • the evaporator consists of a tubular or cylindrical body with end walls, which may be soldered or welded to the main body.
  • a float In the interior of the evaporator a float is arranged, which in a manner known per se controls the inlet valve (not shown).
  • the evaporator also contains the lubricant for the pump or other parts of the system. Special measures may be taken for supplying intermittently a lubricant to the parts to be lubricated.
  • the part of the suction tube located in the evaporator is U-shaped and contacts with the bottom of the evaporator. The end of this part of the tube is located above the level of the lubricant.
  • the lower edge of the bevelled end opening, through which the cooling fluid is sucked off, is substantially in level with the lubricant.
  • Fig. 1 shows the upper part of a refrigerator of this invention.
  • Fig. 2 is a perspective view, showing an evaporator
  • Fig. 3 is a sectional view, showing part of an evaporator.
  • i denotes the side walls of the refrigerator casing and 2 denotes the cooling chamber.
  • the upper end of the casing is tightly closed. by a cover 3.
  • the side walls I are formed with shoulders 4 adapted to serve as seats for the bottom of the pump casing, which in this embodiment of the invention consists of two metal plates 1 with an intermediate layer 5 of a heat insulating material. This structure is detachably mounted upon the shoulders 4, e. g., by means of screws 4
  • the evaporator l9 which together with the ice container 2
  • the pump casing 9 proper is shown to be mounted on a raised portion 8 of the plate I.
  • I0 is the cover of the pump casing and II is an inlet tube.
  • the plate 1 also carriesthe condenser l2. In front of the condenser the motor I4 is fulcrumed upon plate 1 in a tip bearing I6.
  • a fan I3 is keyed to the motor shaft.
  • a helical spring or other pressure means I5 is engaged at one end on the motor casing and at the other end on the pump casing, so that the driving belt I8 is permanently tightened.
  • the cooling fluid is supplied from the evaporator I9 to the pump through a supply tube 20, which passes through the base plate structure 5, 1, I and communicates with the pump inlet ll. 2
  • the condenser l2 and the evaporator "3 are connected by way of a return tube (not shown), through which the condensed cooling fluid flows back into the evaporator.
  • the pump and the condenser communicate through a tube 22.
  • Adjacent the motor I4 is arranged a switch 23. This switch controls the motor circuit and when the motor tilts over to the left as shown in Fig. 1 and actuates the switch, the mo tor circuit is opened.
  • the vaporizer I9 is filled with a cooling fluid which is vaporized and consumes heat. This heat is withdrawn from the cooling chamber 2, and ice is formed in said chamber onthe carrier 2
  • the vaporized cooling fluid is sucked off by the pump 9, l0 through the tube 20 and the inlet II and is then forced through the tube 22 into the condenser l2.
  • the cooling fluid In the condenser the cooling fluid is condensed and it flows back in liquid form into the evaporator l9 through the return tube and an accumulator; This completes the cooling cycle.
  • the evaporator shown in Fig. 2 comprises a casing 24 with end members 25 and 26, an ice carrier and a sleeve 21 adapted to be connected to the suction tube. All these parts form an integral body shaped or cast in a corrosionproof and acid-proof metal, preferably a light metal alloy.
  • the suck-off and oil supply tube 28 communicating with the interior of the evaporator may also be made integral with the evaporator proper or may be formed or cast independently.
  • the carrier 30 is shown to be formed integral with the evaporator and it preferably has communicating hollow spaces 3
  • the ice carrier forms a U-shaped pocket which is open on three sides. This is of advantage because the cold air will readily flow off over this U-shaped body.
  • the cooling of the cooling chamber is also accelerated and a greater efliciency is achieved than before.
  • Fig. 3 shows part of a simple cylindrical evaporator l9a; the bottom or end members may be welded to the main evaporator body.
  • 280 denotes a suction tube whichleads from the evaporator to the pump and which may be welded or soldered to the evaporator.
  • the end of the tube projecting into the evaporator is U-shaped and projects to the bottom of the evaporator and then up again, above the level'32 of the cooling fluid.
  • the opening 29a at the end of the tube is bevelled. The lower end of this opening extends into the neighborhood of the oil level 32a.
  • the cooling fluid in the evaporator will be intermittently drawn 01f; through the same opening the gasifled cooling fluid is sucked off.
  • a cooling system comprising in combination, a pump, an electromotor, a belt and pulley drive between said pump and said electromotor, a tip bearing for said motor, a motor circuit, a switch in saidv circuit adapted to be automatically operated by said motor and to open said circuit when the belt slides off the pulleys, and a common mounting plate for all said elements.
  • a cooling system comprising in combination, a cooling-chamber, a pump, an electromotor, a condenser, an evaporator pro- J'ecting into the cooling chamber, an icecarrier, and a common removable mounting plate for the pump, the electromotor, the condenser, the evaporator and the ice carrier, said mounting plate having a heat insulating layer on its underside, being raised in part away from said layer where it extends underneath said pump in order to provide additional insulation in the form of a layer of air, and extending over andserving as a covering and separating partition for said cooling chamber.
  • a cooling system comprising in combination, a pump casing, an electromotor, a motor circuit, a condenser, an evaporator, a belt and pulley drive between said electromotor and said pump casing, automatically operating switching means for opening said motor circuit when the tension on said belt is reduced, and a removable pump casing bottom member serving as a common mounting plate for said electromotor, said condenser, said evaporator and said switching means.
  • a cooling system comprising in combination, a pump casing, an electromotor, a motor circuit, a condenser, an evaporator, a belt and pulley drive between said electromotor and said pump casing, automatically operating switching means for opening said motor circuit when the. tension on said belt is reduced, a conduit between the evaporator and the pump casing, another conduit between the pump casing and the condenser, a return conduit leading from the condenser to the evaporator, and a removable pump casing bottom member serving as a common mounting plate for said electromotor, said condenser, said evaporator and said switching means.
  • a cooling system comprising in combination, a pump, an electromotor, a motor circuit, a condenser, an evaporator, a belt and pulley drive between said electromotor and said pump, automatically operating switching means for opening said motor circuit when the the condenser, the evaporator, the switching means and the ice. container.
  • a motor circuit for opening said motor circuit when the tension on said belt is reduced a conduit between the evaporator and the pump, another conduit between the pump and the condenser, a return conduit leading from the consider to the evaporator, a cooling chamber, a hollow ice carrier in said cooling chamber, and a removable pump casing bottom member serving as a common mounting plate for the electromotor, the condenser, the evaporator, the switching means and the ice container, and also serving as a heat insulating cover for said cooling chamber.
  • a cooling system comprising a pump casins, an electromotor, a motor circuit, a cut-out in said motor circuit, a tip bearing for said electromotor, a condenser, an evap-d orator, ,a belt and pulley drive for transmitting power from said electromotor to said pump casing, means adapted to become automatically operative and to cause said electromotor to actuate said cut-out when the transmission of force from the motor is disturbed, and a removable pump casing bottom member, serving as a comm n mounting plate for the tip bearing, the cut-o t, k
  • casing bottom bottom member serving as a common mounting plate for the tip bearing, the cut-- out, the condenser and the evaporator, said automatically operating means, consisting of a pressure spring the one end of which is seated on the electromotor and the other end of which is seated on the pump casing.
  • a cooling system comprising a pump, an electromotor, a motor circuit, a'
  • said automatically operating means consisting of a beitstretcher.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Devices That Are Associated With Refrigeration Equipment (AREA)

Description

G. THOMAS REFRIGERATOR Filed June 22, 1936 Inventor Patented Apr. 23, 1940' UNITED STATES REFRIGERATOR Gustav Thomas, Dresden, Germany Application June 22, 1936, Serial No. 86,689 In Germany June 21, 1935 9 Claims.
(Granted The present invention relates to a refrigerator, the cooling system of which comprises a piston pump, an electromotor, a condenser, a heat exchange vessel and an evaporator. In the hitherto known refrigerators the individual parts of the cooling system were mounted independent of each other in the casing, and when the arrangement is to be repaired or controlled the entire refrigerator must be taken apart. This is a serious drawback, since this disassembling of the parts requires much time and consequently involves high costs of repair. On the other hand the costs of manufacture are also high, since the individual mountingof the parts is a complicated task. The evaporator must be mounted subsequently to the other parts and that is another drawback. The main object of -this invention is to remove these disadvantages. All parts of the cooling system are mounted together on a suitable formed and removable bottom of the piston pump casing. This bottom serves at the same time as an insulated cover plate for the cooling chamber. The
bottom of the pump casing is preferably cast or stamped from a corrosion-proof and acid-proof light metal alloy or from other metals. This construction of the refrigerator renders it possible to assemble all parts of the cooling system outside of the refrigerator casing and to insert the assembled structure into the casing by means of simple manipulations. When the cooling system is to be repaired or adjusted it may be removed from thecasing by reversing the simple operation just described. This arrangement also involves the advantage, that the cooling system can be moved, e. g., transported to a testing room without the bulky casing. The cooling system is not mounted in the refrigerator casing until it has been tested. The bottom of the pump casing is preferably arranged to serve as a heat insulating plate.
The bottom member is preferably cast or stamped with clearances or raised portions, for instance right below the pump casing, thus providing an additional insulation, consisting of a layer of air.
According to the invention the refrigerator is also equipped with. an automatic switch, which opens the motor circuit, when the transmission of power from the motor to the compressor is disturbed. When in similar arrangements of the old art the driving belt slid oif one of the pulleys, the motor often ran away and finally attained so high a speed that it broke apart endangering the surrounding; or the motor ran without a load fora long time and current Was wasted.
under the provisions of sec. 14, act of March 2, 1927; 357 0. G. 5)
The motor is preferably tiltably arranged on the bottom or base plate of the pump casing in such a manner, that under the influence of a spring or its own weight or by some other expedient it will tilt out of its normal position and 5 actuate the switch, when the tension of the belt is reduced. It is also possible to arrange a belt stretcher in such a manner, that it will actuate the switch when the driving belt slides off the pulleys.
According to the invention the evaporator consists of a tubular or cylindrical body with end walls, which may be soldered or welded to the main body. In the interior of the evaporator a float is arranged, which in a manner known per se controls the inlet valve (not shown). The evaporator also contains the lubricant for the pump or other parts of the system. Special measures may be taken for supplying intermittently a lubricant to the parts to be lubricated. The part of the suction tube located in the evaporator is U-shaped and contacts with the bottom of the evaporator. The end of this part of the tube is located above the level of the lubricant. The lower edge of the bevelled end opening, through which the cooling fluid is sucked off, is substantially in level with the lubricant.
The invention is illustrated schematically by way of example in the accompanying drawing, in which Fig. 1 shows the upper part of a refrigerator of this invention.
Fig. 2 is a perspective view, showing an evaporator,
Fig. 3 is a sectional view, showing part of an evaporator.
i denotes the side walls of the refrigerator casing and 2 denotes the cooling chamber. The upper end of the casing is tightly closed. by a cover 3. The side walls I are formed with shoulders 4 adapted to serve as seats for the bottom of the pump casing, which in this embodiment of the invention consists of two metal plates 1 with an intermediate layer 5 of a heat insulating material. This structure is detachably mounted upon the shoulders 4, e. g., by means of screws 4 The evaporator l9, which together with the ice container 2| is arranged below the insulated metal plate, may for instance operate with sulfurdioxide.
The pump casing 9 proper is shown to be mounted on a raised portion 8 of the plate I. I0 is the cover of the pump casing and II is an inlet tube. The plate 1 also carriesthe condenser l2. In front of the condenser the motor I4 is fulcrumed upon plate 1 in a tip bearing I6.
A fan I3 is keyed to the motor shaft. A helical spring or other pressure means I5 is engaged at one end on the motor casing and at the other end on the pump casing, so that the driving belt I8 is permanently tightened.
The cooling fluid is supplied from the evaporator I9 to the pump through a supply tube 20, which passes through the base plate structure 5, 1, I and communicates with the pump inlet ll. 2| is an ice carrier, which is suspended from the evaporator IS. The condenser l2 and the evaporator "3 are connected by way of a return tube (not shown), through which the condensed cooling fluid flows back into the evaporator. The pump and the condenser communicate through a tube 22. Adjacent the motor I4 is arranged a switch 23. This switch controls the motor circuit and when the motor tilts over to the left as shown in Fig. 1 and actuates the switch, the mo tor circuit is opened.
The described arrangement operates in the following manner:
The vaporizer I9 is filled with a cooling fluid which is vaporized and consumes heat. This heat is withdrawn from the cooling chamber 2, and ice is formed in said chamber onthe carrier 2|. The vaporized cooling fluid is sucked off by the pump 9, l0 through the tube 20 and the inlet II and is then forced through the tube 22 into the condenser l2. In the condenser the cooling fluid is condensed and it flows back in liquid form into the evaporator l9 through the return tube and an accumulator; This completes the cooling cycle.
When the driving belt l8 slides off a pulley th spring 15 at once swings the motor to the left, away from the pump, and the switch 23 is actuated and interrupts the-motor circuit, so that the motor is stopped instantaneously and no damage will be caused.
If it is desired to repair or adjust the apparatus it is only necessary to loosen the screws 4 retaining the plate structure 5, I on shoulders 4 and to remove this structure from the refrigerator casing together with the whole apparatus mounted thereon. The electro-motor, the drive, the pump, the evaporator and the condenser are now accessible from all sides and can easily be repaired or adjusted.
The evaporator shown in Fig. 2 comprises a casing 24 with end members 25 and 26, an ice carrier and a sleeve 21 adapted to be connected to the suction tube. All these parts form an integral body shaped or cast in a corrosionproof and acid-proof metal, preferably a light metal alloy. The suck-off and oil supply tube 28 communicating with the interior of the evaporator may also be made integral with the evaporator proper or may be formed or cast independently. The carrier 30 is shown to be formed integral with the evaporator and it preferably has communicating hollow spaces 3|, which in turn communicate directly with the float chamber 24. Through this arrangement a thorough utilization of the cooling fluid is rendered possible.
The ice carrier forms a U-shaped pocket which is open on three sides. This is of advantage because the cold air will readily flow off over this U-shaped body. The cooling of the cooling chamber is also accelerated and a greater efliciency is achieved than before.
Fig. 3 shows part of a simple cylindrical evaporator l9a; the bottom or end members may be welded to the main evaporator body. 280 denotes a suction tube whichleads from the evaporator to the pump and which may be welded or soldered to the evaporator. The end of the tube projecting into the evaporator is U-shaped and projects to the bottom of the evaporator and then up again, above the level'32 of the cooling fluid. The opening 29a at the end of the tube is bevelled. The lower end of this opening extends into the neighborhood of the oil level 32a.
Through this bevelled opening oil floating on.
the cooling fluid in the evaporator will be intermittently drawn 01f; through the same opening the gasifled cooling fluid is sucked off.
Some of the subject matter herein disclosed is dealt with and claimed in detail in a continuation-in-part of the application of the inventor herein, entitled Refrigerant evaporator, and filed under date of July 27, 1938, under Serial Number 221,493. 7
I claim:
1. In a refrigerator, a cooling system comprising in combination, a pump, an electromotor, a belt and pulley drive between said pump and said electromotor, a tip bearing for said motor, a motor circuit, a switch in saidv circuit adapted to be automatically operated by said motor and to open said circuit when the belt slides off the pulleys, and a common mounting plate for all said elements.
2. In a refrigerator, a cooling system comprising in combination, a cooling-chamber, a pump, an electromotor, a condenser, an evaporator pro- J'ecting into the cooling chamber, an icecarrier, and a common removable mounting plate for the pump, the electromotor, the condenser, the evaporator and the ice carrier, said mounting plate having a heat insulating layer on its underside, being raised in part away from said layer where it extends underneath said pump in order to provide additional insulation in the form of a layer of air, and extending over andserving as a covering and separating partition for said cooling chamber.
3. In a refrigerator, a cooling system comprising in combination, a pump casing, an electromotor, a motor circuit, a condenser, an evaporator, a belt and pulley drive between said electromotor and said pump casing, automatically operating switching means for opening said motor circuit when the tension on said belt is reduced, and a removable pump casing bottom member serving as a common mounting plate for said electromotor, said condenser, said evaporator and said switching means.
4. In a refrigerator, a cooling system comprising in combination, a pump casing, an electromotor, a motor circuit, a condenser, an evaporator, a belt and pulley drive between said electromotor and said pump casing, automatically operating switching means for opening said motor circuit when the. tension on said belt is reduced, a conduit between the evaporator and the pump casing, another conduit between the pump casing and the condenser, a return conduit leading from the condenser to the evaporator, and a removable pump casing bottom member serving as a common mounting plate for said electromotor, said condenser, said evaporator and said switching means.
5. In a refrigerator, a cooling system comprising in combination, a pump, an electromotor, a motor circuit, a condenser, an evaporator, a belt and pulley drive between said electromotor and said pump, automatically operating switching means for opening said motor circuit when the the condenser, the evaporator, the switching means and the ice. container.
6. In a refrigerator, a cooling ,sy'stem'co prising in combination, a pump, an electromotor,
a motor circuit, a condenser, an evaporator, a belt and pulley drive between said electromotor and said pump, automatically operating switchin means for opening said motor circuit when the tension on said belt is reduced a conduit between the evaporator and the pump, another conduit between the pump and the condenser, a return conduit leading from the consider to the evaporator, a cooling chamber, a hollow ice carrier in said cooling chamber, and a removable pump casing bottom member serving as a common mounting plate for the electromotor, the condenser, the evaporator, the switching means and the ice container, and also serving as a heat insulating cover for said cooling chamber.
7. In a refrigerator, a cooling system comprising a pump casins, an electromotor, a motor circuit, a cut-out in said motor circuit, a tip bearing for said electromotor, a condenser, an evap-d orator, ,a belt and pulley drive for transmitting power from said electromotor to said pump casing, means adapted to become automatically operative and to cause said electromotor to actuate said cut-out when the transmission of force from the motor is disturbed, and a removable pump casing bottom member, serving as a comm n mounting plate for the tip bearing, the cut-o t, k
, casing bottom bottom member serving as a common mounting plate for the tip bearing, the cut-- out, the condenser and the evaporator, said automatically operating means, consisting of a pressure spring the one end of which is seated on the electromotor and the other end of which is seated on the pump casing.
9. In a refrigerator, a cooling system comprising a pump, an electromotor, a motor circuit, a'
cut-out in said motor circuit, a tip bearing for said electromotor, a condenser, an evaporator, a
belt and pulley drive for transmitting power from said electromotor to said pump, means adapted to become automatically operative and to cause said electromotor to actuate said cut-out when the transmission of force from the motor is disturbed, and a removablebottom member, serving as a common moimting plate for the pump,
the tip bearing, the cut-out, the condenser. and the evaporator, said automatically operating means consisting of a beitstretcher.
GUBTAVYI'HOMAS.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2429934A (en) * 1944-08-17 1947-10-28 Melvin S Groh Removable refrigerating unit

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2429934A (en) * 1944-08-17 1947-10-28 Melvin S Groh Removable refrigerating unit

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