US1984321A - Regulator for refrigerative systems - Google Patents

Regulator for refrigerative systems Download PDF

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Publication number
US1984321A
US1984321A US511118A US51111831A US1984321A US 1984321 A US1984321 A US 1984321A US 511118 A US511118 A US 511118A US 51111831 A US51111831 A US 51111831A US 1984321 A US1984321 A US 1984321A
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air
refrigerant
refrigerative
current
connection
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US511118A
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Schwitzer Louis
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General Fire Extinguisher Co
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General Fire Extinguisher Co
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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
    • F25DREFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D21/00Defrosting; Preventing frosting; Removing condensed or defrost water
    • F25D21/02Detecting the presence of frost or condensate
    • F25D21/025Detecting the presence of frost or condensate using air pressure differential detectors

Definitions

  • REGULATOR FOR REFRIGERATIVE SYSTEMS Filed Jan. 26, 1931 s sheets-sheet 1 'I N VEN TOR. n l oz//J Sc//W/ rz EA.
  • This invention relates to the control for a re frigerative system and particularly for defrosting the same. reference beinghad to the copending application of ThomasW. Carraway,
  • the principal object ofjthe linvention is to provide a control for a refrigerating system wherein the control member is of relatively large area so as to extend over substantially all of the surface of the refrigerative unit.
  • said member is affected by the fiow of air through all parts of the unit and isl not confined to the flow through a comparatively small portion thereof. This permits the proper control beinghad irrespective of certain portions of the refrigerating unit being defrosted more rapidly than other portions thereof.
  • Another feature ⁇ of the invention resides in the housing of the member within the radiator housing so thatit will not be exposed in such manner as to be damaged or affected by han dling of the unit and external mediums.
  • Another feature of the invention resides in the provision of a drainage pan immediately below the member for receiving and draining oil? drippings from the moisture accumulating thereon.
  • the air striking the member Lis of high relative humidity.
  • the screen of which themember is formed permits the air to pass therethrough while the mesh attracts the moisture and removes a large portion thereof from the air causing it to drop into the drain pan and be carried away. 'I'his permits of the unit being located above portions a of the plant where it is undesirable to have' an moisture drip therefrom.
  • Another feature of the invention resides in the provision of deflecting vblades mounted in front of the radiator for directing'the cold air blown therethrough upwardly, while catching a portion of the remaining moisture in the air and permitting it to drain rearwardly into the drain pan.
  • Fig. 1 is'a central vertical section through the radiator showing the control member in free hanging position with the mercury tube switch broken for shutting off the refrigeratingmedium .when the radiatorV is frosted.
  • Fig...2 is the same as Fig. 1 'showing a portion thereof with the member extended, the switch being closed andv the valve opened for the refrigerative medium 55 to pass through the radiator when in defrosted 19:1. sum No. 511.118 (ci. sz-yz) condition.
  • Fig. 3 is a diagrammatic view of the refrigerating system.
  • Fig. 4 is the same as Fig. 2, showing a modied form.
  • Fig. 5 is a front elevation of the screened or perforated deflector.
  • Fig. 6 shows a front elevation of the heat absorbing element.
  • a refrigerating unit comprising the radiator sections 10, headers 11 and tie rods 12.
  • a bracket 13 supporting the motor 14 for driving the fan 15 whereby air will be forced through the radiator and over the surfaces thereof.
  • a refrigerant suction line 16 Connected to the top header 11, there is a refrigerant suction line 16 and connected with the lower header there is a refrigerant supply line 17.
  • an electrically controlled valve 18 of the solenoid type Mounted in the suction line there is an electrically controlled valve 18 of the solenoid type.
  • a source of power 19 is provided which is connected to the' motor 14 for driving the same, and also to the electric valve 18 for controlling the action thereof.
  • a mercury switch 20 In the circuit to the valve there is a mercury switch 20 which is controlled by the control member or defrosting vane 21.
  • the valve circuit is so arranged that when the vane 21 which is pivotally supported upon the top header 11 directly in front of and slightly spaced from the radiator, hangs in its normal vertical position, the mercury switch is open so that the circuit is broken, whereby the valve 18 will be deenergized for closing the suction line 16. This occurs when the radiator is frosted so that very little air from the fan 15 can pass therethrough. Thus, the cooling medium ceases to flow through the radiator, which thereupon becomes gradually warmed through the warmer air impacting thereon, whereby the frost is melted and carried away by the air current passing over the surfaces of the radiator.
  • the mercury switch When sufficient frost has been removed in this manner so that the air current striking the member 21 forces it forwardly through a. slight arc to a position shown in Fig. 2, the mercury switch will be moved to a. circuit closing position for energizing the valve and permitting the fiow of refrigerating medium to be renewed. Thereupon, there will be a cooling action until such time as frost again accumulatesl on the radiator surface to such a ⁇ degree as to retard the passage of air over the surfaces thereof.
  • the member or vane 21 extends over the greater portion of the face of the radiator and is formed of asuitable frame supporting a screen or apertured surface. This permits of the member extending over a much greater area than is possible with a solid screen, and, therefore, affords a control which is affected by substantially the entire area of the radiator rather than only a portion thereof. Furthermore, the screen acts as an eliminator to remove from the passing air an appreciable portion of the moisture entrained in it. This moisture collects on the screen and drains downward to finally drip from the lower edge thereof.
  • a housing 22 having a drain pan 23 at the bottom thereof and a drainage outlet 24.
  • the forward portion of the ⁇ housing is open and provided with a plurality of laterally extending deiiectors 25 having upwardly curved surfaces 26 which act to direct the air forced therethrough upwardly and cause any moisture deposited thereon to drain rearwardly into the drainage pan 23.
  • the casing 123 is made with one upward sweep in pla'ce of the provision of a plurality of deflectors. This is for the purpose of providing a single defiector 122 for directing the air upwardly and draining the moisture in the same manner as is proposed by the several defiectors shown in Figs. 1 and 2.
  • the greater portion of the moisture precipitated by the air in its defrosting action will be drained away so as to avoid the otherwise objectionable drippage from the apparatus.
  • the protection of the control member by the enclosing housing will eliminate unnecessary damage and permit of more perfect control unaffected by outside influence.
  • the defiectors 25 for directing the cold air upwardly will add to the efficiency of the apparatus by discharging the ⁇ cold air over a greater area, all of which greatly aids the commercial value and efficiency thereof.
  • a refrigerative system comprising a heat exchanger having connection with a supply of refrigerant; means in said connection for controlling the flow of refrigerant through the exchanger; means for moving air past the exchanger; and a displaceable member for actuating said control means in accordance with the air ow past said exchanger; and a housing extending from said exchanger and adapted to protect the displaceable member while permitting operative movements thereof.
  • a refrigerative system comprising a heatl exchanger having connection with a supply of refrigerant; means in said connection for controlling the fiow of refrigerant through the exchanger; means for moving air past the exchanger; and a movable perforated member arranged in the path of air flow from the exchanger adapted to permit air to pass through the member and to be moved by said air for,actuating said control means.
  • a refrigerative system comprising a heat exchanger having connection with a supply of refrigerant; means in said connection for controlling the flow of refrigerant through the exchanger; means for moving air past the exchanger; means actuated by said air movement for operating said flow controlling means; and meansarranged in the path of air flow beyond said air actuated means for entrapping moisture carried from the exchanger by the air.
  • a refrigerative system including a heat absorbing element having connection with a supply of refrigerant, means in said connection for controlling the flow of refrigerant through the element, means for forcing a current of air over the surfaces of said element to remove the free moisture therefrom, a movable member associated with said element and actuated by the current of moisture laden air for effecting the operation of said control means, and a drain pan having a drainage conduit positioned under said member for receiving precipitated moisture therefrom and causing the same to be carried away.
  • a refrigerative system including a heat absorbing element having connection with a supply -of refrigerant, means in said connection for controlling the flow of refrigerant through the element, means for forcing a current of air over the'surfaces of said element, a displaceable member associated with said element and actuated by the current of air for effecting the operation of said control means, a casing surrounding said element, and a defiector mounted on said casing for directing the current of air passing said member.
  • a refrigerative system including a heat absorbing element having connection with a supply of refrigerant, means in said connection for controlling the flow of refrigerant through the element, means for forcing a current of air over the surfaces of said element, a casing surrounding said element, and a displaceable member, associated with said element and actuated by the current of air for effecting the operation of said control means mounted within said casing.
  • a refrigerative system including a heat absorbing element having connection with a supply of refrigerant, means in said connection for controlling the flow of refrigerant through the element, means for forcing a current of air over the surfaces of said element, a casing surrounding said element, a dei'lector formed on the front of said casing, and a displaceable member, associated with said element and actuated by the current of air for effecting the operation of said control means, mounted between said element and the defiector of said casing.
  • a refrigerative system including a heat absorbing element having connection with a supply of refrigerant, means in said connection for controlling the flow of refrigerant through the element, means for forcing a current of air over the surfaces of said element, a deiiector for the air current positioned in front of said element, and a displaceable member, associated with said element and actuated by the current of air for eecting the operation of said control means, mounted to extend between said element and defiector.
  • a refrigerative system including a heat absorbing element having connection with a supply of refrigerant, means in said connection for controlling the iiow of refrigerant through the element, means for forcing a current of air over the surfaces of said element, a displaceable member associated with said element and actuated by the current of air for effecting the operation of said control means, a casing surrounding said element, a deiiector mounted on said casing for directing the current of air passing said member, said deflector having an upwardly curved surface for deiecting the ⁇ air upwardly while causing moisture precipitation to drain rearwardly, and a drainage pan positioned on the underside of said casing for receiving the moisture drained from said deiiector and said member.
  • a refrigerative system including a heat absorbing element having connection with a supply of refrigerant, means in said connection for controlling the flow of refrigerant through the element, means for forcing a current of air over the surfaces of said element, a screen member associated with saidelement and actuated by the current of air for veiiecting the operation ot said control means, a casing surrounding said element, a deiiector ⁇ mounted on said casing tor directing the current. of air passing said member, said deiiector having an upwardly curved surface for defiecting the air upwardly while causing moisture precipitation to drain rearwardly, and. a drainage pan positioned on the underside of said casing for receiving the moisture drained from said deector and said member.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Devices For Blowing Cold Air, Devices For Blowing Warm Air, And Means For Preventing Water Condensation In Air Conditioning Units (AREA)

Description

Dec. ll, 1934. sCHwn-ZAER 1,984,321
REGULATOR FOR REFRIGERATIVE SYSTEMS Filed Jan. 26, 1931 s sheets-sheet 1 'I N VEN TOR. n l oz//J Sc//W/ rz EA.
A TTORNEYJ.
D.11,1934. LSCHWWZER. 1,984,321
REGULATOR` FOR REFRIGERATIVE SYSTEMS Filed Jan. 26, 1931 5 Sheets-Sheet 2 IN VEN TOR. L au/.s .5 cf/ w/ rze-A.
- fyi/WM A TTORNEYS.
D- 11, 1,934 L. scHwrrzER y. 1,984,321
REGULATOR FOR REFRIGERATIVB SYSTEMS Filed Jan. 26, 1931 5 Sheets-Sheet 3 [C EL l INVENTOR.
L aufs ch'w/ rzff?.
ZMYMMf/@ ATTORNEYS,
Patented Dec. 11, 1934 REGULATOR FOR l REFBIGEBATIVE STEMS Louis Schwimm-Indianapolis, Ina.. mmm, by
meme assignments, to General Fire Extingnisher Company, Providence, B. I., a corpo- T ration of Delaware Application January 26,
` Y .1l Claims. This invention relates to the control for a re frigerative system and particularly for defrosting the same. reference beinghad to the copending application of ThomasW. Carraway,
`Serial N0. 480,594, filed September 8, 1930.
The principal object ofjthe linvention is to provide a control for a refrigerating system wherein the control member is of relatively large area so as to extend over substantially all of the surface of the refrigerative unit. By means thereof, said member is affected by the fiow of air through all parts of the unit and isl not confined to the flow through a comparatively small portion thereof. This permits the proper control beinghad irrespective of certain portions of the refrigerating unit being defrosted more rapidly than other portions thereof. l
Another feature `of the invention resides in the housing of the member within the radiator housing so thatit will not be exposed in such manner as to be damaged or affected by han dling of the unit and external mediums.
Another feature of the invention resides in the provision of a drainage pan immediately below the member for receiving and draining oil? drippings from the moisture accumulating thereon. In the defrosting action the air striking the member Lis of high relative humidity. lThe screen of which themember is formed permits the air to pass therethrough while the mesh attracts the moisture and removes a large portion thereof from the air causing it to drop into the drain pan and be carried away. 'I'his permits of the unit being located above portions a of the plant where it is undesirable to have' an moisture drip therefrom.
Another feature of the invention resides in the provision of deflecting vblades mounted in front of the radiator for directing'the cold air blown therethrough upwardly, while catching a portion of the remaining moisture in the air and permitting it to drain rearwardly into the drain pan.
The full nature of the invention will be more clearly understood from the accompanying drawings and the following description and claims:
Fig. 1 is'a central vertical section through the radiator showing the control member in free hanging position with the mercury tube switch broken for shutting off the refrigeratingmedium .when the radiatorV is frosted. Fig..2 is the same as Fig. 1 'showing a portion thereof with the member extended, the switch being closed andv the valve opened for the refrigerative medium 55 to pass through the radiator when in defrosted 19:1. sum No. 511.118 (ci. sz-yz) condition. Fig. 3 is a diagrammatic view of the refrigerating system. Fig. 4 is the same as Fig. 2, showing a modied form. Fig. 5 is a front elevation of the screened or perforated deflector. Fig. 6 shows a front elevation of the heat absorbing element.
In the drawings there is shown a refrigerating unit comprising the radiator sections 10, headers 11 and tie rods 12.
Mounted at the rear of the radiator there is a bracket 13 supporting the motor 14 for driving the fan 15 whereby air will be forced through the radiator and over the surfaces thereof. Connected to the top header 11, there is a refrigerant suction line 16 and connected with the lower header there isa refrigerant supply line 17. Mounted in the suction line there is an electrically controlled valve 18 of the solenoid type. A source of power 19 is provided which is connected to the' motor 14 for driving the same, and also to the electric valve 18 for controlling the action thereof. In the circuit to the valve there is a mercury switch 20 which is controlled by the control member or defrosting vane 21.
The valve circuit is so arranged that when the vane 21 which is pivotally supported upon the top header 11 directly in front of and slightly spaced from the radiator, hangs in its normal vertical position, the mercury switch is open so that the circuit is broken, whereby the valve 18 will be deenergized for closing the suction line 16. This occurs when the radiator is frosted so that very little air from the fan 15 can pass therethrough. Thus, the cooling medium ceases to flow through the radiator, which thereupon becomes gradually warmed through the warmer air impacting thereon, whereby the frost is melted and carried away by the air current passing over the surfaces of the radiator.
When sufficient frost has been removed in this manner so that the air current striking the member 21 forces it forwardly through a. slight arc to a position shown in Fig. 2, the mercury switch will be moved to a. circuit closing position for energizing the valve and permitting the fiow of refrigerating medium to be renewed. Thereupon, there will be a cooling action until such time as frost again accumulatesl on the radiator surface to such a `degree as to retard the passage of air over the surfaces thereof.
The member or vane 21 extends over the greater portion of the face of the radiator and is formed of asuitable frame supporting a screen or apertured surface. This permits of the member extending over a much greater area than is possible with a solid screen, and, therefore, affords a control which is affected by substantially the entire area of the radiator rather than only a portion thereof. Furthermore, the screen acts as an eliminator to remove from the passing air an appreciable portion of the moisture entrained in it. This moisture collects on the screen and drains downward to finally drip from the lower edge thereof.
In order to protect the vane 21 there is a housing 22 having a drain pan 23 at the bottom thereof and a drainage outlet 24. The forward portion of the` housing is open and provided with a plurality of laterally extending deiiectors 25 having upwardly curved surfaces 26 which act to direct the air forced therethrough upwardly and cause any moisture deposited thereon to drain rearwardly into the drainage pan 23.
In the modified form shown in Fig. 4, the casing 123 is made with one upward sweep in pla'ce of the provision of a plurality of deflectors. This is for the purpose of providing a single defiector 122 for directing the air upwardly and draining the moisture in the same manner as is proposed by the several defiectors shown in Figs. 1 and 2.
In view of the above, it will be noted that the greater portion of the moisture precipitated by the air in its defrosting action will be drained away so as to avoid the otherwise objectionable drippage from the apparatus. Furthermore, the protection of the control member by the enclosing housing will eliminate unnecessary damage and permit of more perfect control unaffected by outside influence. The defiectors 25 for directing the cold air upwardly will add to the efficiency of the apparatus by discharging the \cold air over a greater area, all of which greatly aids the commercial value and efficiency thereof.
The invention claimed is:
1. A refrigerative system comprising a heat exchanger having connection with a supply of refrigerant; means in said connection for controlling the flow of refrigerant through the exchanger; means for moving air past the exchanger; and a displaceable member for actuating said control means in accordance with the air ow past said exchanger; and a housing extending from said exchanger and adapted to protect the displaceable member while permitting operative movements thereof.
2. A refrigerative system comprising a heatl exchanger having connection with a supply of refrigerant; means in said connection for controlling the fiow of refrigerant through the exchanger; means for moving air past the exchanger; and a movable perforated member arranged in the path of air flow from the exchanger adapted to permit air to pass through the member and to be moved by said air for,actuating said control means.
3. A refrigerative system comprising a heat exchanger having connection with a supply of refrigerant; means in said connection for controlling the flow of refrigerant through the exchanger; means for moving air past the exchanger; means actuated by said air movement for operating said flow controlling means; and meansarranged in the path of air flow beyond said air actuated means for entrapping moisture carried from the exchanger by the air.
4. A refrigerative system including a heat absorbing element having connection with a supply of refrigerant, means in said connection for controlling the flow of refrigerant through the element, means for forcing a current of air over the surfaces of said element to remove the free moisture therefrom, a movable member associated with said element and actuated by the current of moisture laden air for effecting the operation of said control means, and a drain pan having a drainage conduit positioned under said member for receiving precipitated moisture therefrom and causing the same to be carried away.
5. A refrigerative system including a heat absorbing element having connection with a supply -of refrigerant, means in said connection for controlling the flow of refrigerant through the element, means for forcing a current of air over the'surfaces of said element, a displaceable member associated with said element and actuated by the current of air for effecting the operation of said control means, a casing surrounding said element, and a defiector mounted on said casing for directing the current of air passing said member.
6. A refrigerative system including a heat absorbing element having connection with a supply of refrigerant, means in said connection for controlling the flow of refrigerant through the element, means for forcing a current of air over the surfaces of said element, a casing surrounding said element, and a displaceable member, associated with said element and actuated by the current of air for effecting the operation of said control means mounted within said casing.
'7. A refrigerative system including a heat absorbing element having connection with a supply of refrigerant, means in said connection for controlling the flow of refrigerant through the element, means for forcing a current of air over the surfaces of said element, a casing surrounding said element, a dei'lector formed on the front of said casing, and a displaceable member, associated with said element and actuated by the current of air for effecting the operation of said control means, mounted between said element and the defiector of said casing.
8. A refrigerative system including a heat absorbing element having connection with a supply of refrigerant, means in said connection for controlling the flow of refrigerant through the element, means for forcing a current of air over the surfaces of said element, a deiiector for the air current positioned in front of said element, and a displaceable member, associated with said element and actuated by the current of air for eecting the operation of said control means, mounted to extend between said element and defiector.
9. A refrigerative system including a heat absorbing element having connection with a supply of refrigerant, means in said connection for controlling the iiow of refrigerant through the element, means for forcing a current of air over the surfaces of said element, a displaceable member associated with said element and actuated by the current of air for effecting the operation of said control means, a casing surrounding said element, a deiiector mounted on said casing for directing the current of air passing said member, said deflector having an upwardly curved surface for deiecting the `air upwardly while causing moisture precipitation to drain rearwardly, and a drainage pan positioned on the underside of said casing for receiving the moisture drained from said deiiector and said member.
10. A refrigerative system including a heat absorbing element having connection with a supply of refrigerant, means in said connection for controlling the flow of refrigerant through the element, means for forcing a current of air over the surfaces of said element, a screen member associated with saidelement and actuated by the current of air for veiiecting the operation ot said control means, a casing surrounding said element, a deiiector `mounted on said casing tor directing the current. of air passing said member, said deiiector having an upwardly curved surface for defiecting the air upwardly while causing moisture precipitation to drain rearwardly, and. a drainage pan positioned on the underside of said casing for receiving the moisture drained from said deector and said member.
LOUIS SCHWI'I'ZER.
US511118A 1931-01-26 1931-01-26 Regulator for refrigerative systems Expired - Lifetime US1984321A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3004399A (en) * 1958-12-01 1961-10-17 Gen Controls Co Automatic defrost control for refrigerators or heat pump systems
US20090100858A1 (en) * 2007-10-22 2009-04-23 Lg Electronics Inc. Air conditioner

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3004399A (en) * 1958-12-01 1961-10-17 Gen Controls Co Automatic defrost control for refrigerators or heat pump systems
US20090100858A1 (en) * 2007-10-22 2009-04-23 Lg Electronics Inc. Air conditioner

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