US3664769A - Hermetically enclosed small refrigerating machine - Google Patents

Hermetically enclosed small refrigerating machine Download PDF

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US3664769A
US3664769A US32469*[A US3664769DA US3664769A US 3664769 A US3664769 A US 3664769A US 3664769D A US3664769D A US 3664769DA US 3664769 A US3664769 A US 3664769A
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gas
noise
chamber
reducing
metal
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US32469*[A
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Jorgen Dahlman Knudsen
Bendt Wegge Romer
Knud Vagn Valbjorn
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Danfoss AS
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Danfoss AS
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B39/00—Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00
    • F04B39/0027—Pulsation and noise damping means
    • F04B39/0055—Pulsation and noise damping means with a special shape of fluid passage, e.g. bends, throttles, diameter changes, pipes
    • F04B39/0072—Pulsation and noise damping means with a special shape of fluid passage, e.g. bends, throttles, diameter changes, pipes characterised by assembly or mounting
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B39/00—Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00
    • F04B39/12—Casings; Cylinders; Cylinder heads; Fluid connections
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S417/00—Pumps
    • Y10S417/902—Hermetically sealed motor pump unit

Definitions

  • the invention relates to a noise reducing assembly for a refrigeration unit of the hermetically sealed type.
  • the assembly includes walls forming a heat insulation chamber surrounding the noise reducing chamber with a substantially statically contained gas in said heat insulation chamber.
  • the invention relates to a hermetically enclosed small refrigerating machine, theinterior of which is under suction pressure and the sound reducing unit of which is provided with means for limiting the dissipation of heat.
  • the means for limiting the dissipation of heat consist of a coating comprised of a film of plastics material, or of a porous layer of plastics material.
  • This sheathing prevents the hot surface of the noise-reducing unit from being directly swept by the suction gas, so that, due to the low heat-conducting capacity of the filler material, the transfer of heat to the suction gas is reduced.
  • the surface of the noise-reducing unit is prevented from being wetted with oil, so that the transfer of heat to the oil is also prevented. This results in the hot pressure gas carrying a fairly large proportion of its thermal energy outwards and the case is kept at a lower temperature.
  • the sheathings of plastics material are difficult to apply, however.
  • a construction is also known wherein the noise-reducing unit, freely swept by the suction gas, is positioned beneath a protective plate or another component of the compressor in such a manner that it is largely protected against being wetted by sprayed oil.
  • direct heatexchange between the noise-reducing unit and the suction gas has to be accepted.
  • the object of the invention is to provide the noisereducing unit with means for limiting the dissipation of heat, which means can be readily applied in the normal production line handling small refrigerating machines, are largely immune from damage and nevertheless have a very good effect as regards the prevention of heat-transfer.
  • this object is achieved by forming the limiting means as a static gas-cushion, which is contained between the wall of the noise-reducing unit and a metal wall surrounding it ata distance therefrom.
  • the metal wall prevents the surface of the noise-reducing unit from being wetted by oil and prevents the suction gas from sweeping said surface.
  • the metal wall itself may be heat-conducting and also be supported on the Patented May 23, 1972 noise-reducing unit, since the area of contact is relatively small and the whole of the rest of the surface is sep arated from the noise-reducing unit by the thermally insulating gas-cushion. Since the metal Wall forms a rigid shaped part, the distance from the wall of the noisereducing unit, i.e. the size of the gas-cushion, and therefore the effect of the limitation of the heat-transfer can be predetermined quite accurately in terms of construction.
  • the metal wall is soldered directly on to the noise-reducing unit and the gas-cushion consists of the protective gas used in the soldering.
  • a subatmospheric pressure will have been set up in the enclosed gas-cushion compartment during cooling after soldering.
  • the smaller number of gas molecules in the gas-cushion results in a particularly poor heat-transfer.
  • noise-reducing chambers which are each provided with a metal wall on one side only and which lie against each other at their other sides. Despite using only two gas-cushions, both noise-reducing chambers are fully protected against excessive heat dissipation.
  • At least two sheet-metal walls, defining a noise-reducing chamber to have extensions which accommodate part of the pressure piping and form the cylinder head containing the pressure and suction valve chambers, at least the cylinder head projecting beyond the zone of the metal walls enclosing the gas-cushion.
  • FIG. 1 is a side elevation of a noise-reducing chamber according to the invention
  • FIgICi. 2 is a longitudinal section on the line AA of Attached to the valve plate 1 of a cylinder 2 of an enclosed small refrigerating machine, which is positioned in the interior of a case under suction pressure, is a component 3 which forms a cylinder head 4 and a noise-reducing unit 5.
  • the noise-reducing unit is composed of six sheet-metal shaped parts, which are all soldered together.
  • a channel plate 11 which, together with the middle plate 6, forms throttle passages 12 for the gas entering the chamber 7 and for the gas passing into the chamber 9 through an orifice, not illustrated, in the middle plate 6.
  • a limiting wall of the chamber 7 lies against a limiting wall of the chamber 9.
  • the free limiting walls are covered by a first sheet-metal wall 13 for forming a gas-cushion chamber 14 and by a second sheet-metal wall 17 for forming a second gas-cushion chamber 16.
  • These sheet-metal walls are connected to the sheet-metal parts 8 and 10 only 'by a narrow edge portion 17 and 18 respectively. Openings 19 at the lower end of the sheet-metal wall 13 and similar openings at the lower end of the sheet-metal wall permit the refrigerant to pass into the gas-cushion chambers 14 and 16 and there to form a static gas-cushion.
  • the middle plate 6, the channel plate 11 and the first dished sheet-metal part 8 project beyond the sheet-metal Walls 13 and 15 and form the cylinder head 3.
  • the middle plate 6 contains two suction-gas orifices and 21 and a pressure-gas orifice 22.
  • the latter is covered by a pressure-valve element 23.
  • the channel plate 11 incorporates protuberant portions, not visible in the drawing, which seal off from each other suction-valve chambers associated with the orifices 20 and 21 and a pressure valve chamber 24 associated With the orifice 22.
  • the pressure-valve chamber communicates with the noisereducing unit by way of the pressure passage 25 which is likewise formed between the channel plate 11 and the metal plate 6.
  • the orifices 20 and 21 serve both to supply suction gas through passages in the valve plate 1 and to introduce the suction gas into the cylinder 2 by way of the valve plate.
  • the pressure gas is discharged from the noise-reducing unit through a pipe 26.
  • the middle plate 6 has at its edge tabs 27, which are bent over to one side, alternating therewith, tabs 28 bent over to the other side.
  • the remaining sheet-metal parts 8, 10, 11, 13 and 15, contain slots 29 adapted to receive the tabs 27 and 28.
  • the prepared sheet-metal parts 8, 10, 11, 13 and 15 are simply pushed on to the middle plate 6 from both sides, their positions being accurately defined by the tabs 27 and 28 and the slots 29. The parts are then held together by the application of light pressure and passed through a solder ing furnace and soldered together, a very stable component 3 then resulting.
  • a noise reducing assembly for a refrigeration unit of the hermetically sealed type in which the interior thereof is under subatmospheric pressure during operation of the unit comprising, a compressor, first nnperforated wall means forming a noise reducing chamber for receiving a refrigerant gas exhausted by said compressor, second unperforated wall means in spaced relation to said first wall means forming an outer insulating chamber for said noise reducing chamber, a gas substantially statically contained in said outer chamber, said second wall means being soldered to said first wall means and said gas being a protective gas of the type used for soldering.
  • a noise reducing assembly for a refrigeration unit of the hermetically sealed type in which the interior there-, of is under subatrnospheric pressure during operation of the unit comprising, a compressor, first unperforated wall means forming a noise reducing chamber for receiving a refrigerant gas exhausted by said compressor, second wall means in spaced relation to said first wall means forming an outer insulating chamber for said noise reducing chamher, a refrigerant gas substantially statically contained in said outer chamber, said second wall means having an opening formed therein for admitting a refrigerant gas to said outer chamber.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Compressor (AREA)

Abstract

THE INVENTION RELATES TO A NOISE REDUCING ASSEMBLY FOR A REFRIGERATION UNIT OF THE HERMETICALLY SEALED TYPE. THE ASSEMBLY INCLUDES WALLS FORMING A HEAT INSULATING CHAMBER SURROUNDING THE NOISE REDUCING CHAMBER WITH A SUBSTANTIALLY STATICALLY CONTAINED GAS IN SAID HEAT INSULATION CHAMBER.

Description

y 23, 1972 J. 0. KNUDSEN ETAL 3,664,769
HERME'IICALLY ENCLOSED SMALL REFRIGERATING MACHINE Filed Aug. 4, 1969 FIGZ FIG]
KNUD VAGN VALBJORN United States Patent U.S. Cl. 417-312 2 Claims ABSTRACT OF THE DISCLOSURE The invention relates to a noise reducing assembly for a refrigeration unit of the hermetically sealed type. The assembly includes walls forming a heat insulation chamber surrounding the noise reducing chamber with a substantially statically contained gas in said heat insulation chamber.
' The invention relates to a hermetically enclosed small refrigerating machine, theinterior of which is under suction pressure and the sound reducing unit of which is provided with means for limiting the dissipation of heat.
In a known construction of this kind, the means for limiting the dissipation of heat consist of a coating comprised of a film of plastics material, or of a porous layer of plastics material. This sheathing prevents the hot surface of the noise-reducing unit from being directly swept by the suction gas, so that, due to the low heat-conducting capacity of the filler material, the transfer of heat to the suction gas is reduced. Moreover, the surface of the noise-reducing unit is prevented from being wetted with oil, so that the transfer of heat to the oil is also prevented. This results in the hot pressure gas carrying a fairly large proportion of its thermal energy outwards and the case is kept at a lower temperature. The sheathings of plastics material are difficult to apply, however. They require steps which cannot readily be incorporated in the assembly-line method that is usually employed in the manufacture of such refrigerating machines and that consist mainly of metal-working operations. Furthermore, the sheathings of plastics material can suffer damage. The further machining and assembly operations, including the unavoidable welding operations, must therefore be carried out with extra care.
A construction is also known wherein the noise-reducing unit, freely swept by the suction gas, is positioned beneath a protective plate or another component of the compressor in such a manner that it is largely protected against being wetted by sprayed oil. Here, direct heatexchange between the noise-reducing unit and the suction gas has to be accepted.
The object of the invention is to provide the noisereducing unit with means for limiting the dissipation of heat, which means can be readily applied in the normal production line handling small refrigerating machines, are largely immune from damage and nevertheless have a very good effect as regards the prevention of heat-transfer.
According to the invention, this object is achieved by forming the limiting means as a static gas-cushion, which is contained between the wall of the noise-reducing unit and a metal wall surrounding it ata distance therefrom. The metal wall prevents the surface of the noise-reducing unit from being wetted by oil and prevents the suction gas from sweeping said surface. Here, the metal wall itself may be heat-conducting and also be supported on the Patented May 23, 1972 noise-reducing unit, since the area of contact is relatively small and the whole of the rest of the surface is sep arated from the noise-reducing unit by the thermally insulating gas-cushion. Since the metal Wall forms a rigid shaped part, the distance from the wall of the noisereducing unit, i.e. the size of the gas-cushion, and therefore the effect of the limitation of the heat-transfer can be predetermined quite accurately in terms of construction. a
In a preferred construction, the metal wall is soldered directly on to the noise-reducing unit and the gas-cushion consists of the protective gas used in the soldering. A subatmospheric pressure will have been set up in the enclosed gas-cushion compartment during cooling after soldering. The smaller number of gas molecules in the gas-cushion results in a particularly poor heat-transfer.
In order to avoid having to deal with problems of soundness, however, it is also possible to provide an opening at the bottom of the metal wall and to use the refrigerant gas as the gas-cushion. Since the refrigerant gas does not move, this likewise results in low heat-transfer.
Furthermore, use can be made of two noise-reducing chambers which are each provided with a metal wall on one side only and which lie against each other at their other sides. Despite using only two gas-cushions, both noise-reducing chambers are fully protected against excessive heat dissipation.
It is also of advantage for at least two sheet-metal walls, defining a noise-reducing chamber, to have extensions which accommodate part of the pressure piping and form the cylinder head containing the pressure and suction valve chambers, at least the cylinder head projecting beyond the zone of the metal walls enclosing the gas-cushion. By uniting the cylinder head and the noise-reducing unit manufacture is simplified. Additionally, the noise-reducing unit is held in a safe and vibration-free manner. In order to enable the suction valve chambers of the noise-reducing unit to be properly cooled, however, this part of the component projects from the metal walls.
The invention will now be described in more detail by reference to an embodiment illustrated in the drawing, wherein:
FIG. 1 is a side elevation of a noise-reducing chamber according to the invention, and FIgICi. 2 is a longitudinal section on the line AA of Attached to the valve plate 1 of a cylinder 2 of an enclosed small refrigerating machine, which is positioned in the interior of a case under suction pressure, is a component 3 which forms a cylinder head 4 and a noise-reducing unit 5.
The noise-reducing unit is composed of six sheet-metal shaped parts, which are all soldered together. A middle plate 6, together with a dished sheet-metal part 8, forms a first noise-reducing chamber 7 on one side and, together with a second dished sheet-metal part 10, forms a second noise-reducing chamber 9 on the other side. Between the middle plate 6 and the sheet-metal part 8 is inserted a channel plate 11 which, together with the middle plate 6, forms throttle passages 12 for the gas entering the chamber 7 and for the gas passing into the chamber 9 through an orifice, not illustrated, in the middle plate 6.
A limiting wall of the chamber 7 lies against a limiting wall of the chamber 9. The free limiting walls are covered by a first sheet-metal wall 13 for forming a gas-cushion chamber 14 and by a second sheet-metal wall 17 for forming a second gas-cushion chamber 16. These sheet-metal walls are connected to the sheet- metal parts 8 and 10 only 'by a narrow edge portion 17 and 18 respectively. Openings 19 at the lower end of the sheet-metal wall 13 and similar openings at the lower end of the sheet-metal wall permit the refrigerant to pass into the gas- cushion chambers 14 and 16 and there to form a static gas-cushion.
The middle plate 6, the channel plate 11 and the first dished sheet-metal part 8 project beyond the sheet- metal Walls 13 and 15 and form the cylinder head 3. For this purpose the middle plate 6 contains two suction-gas orifices and 21 and a pressure-gas orifice 22. The latter is covered by a pressure-valve element 23. The channel plate 11 incorporates protuberant portions, not visible in the drawing, which seal off from each other suction-valve chambers associated with the orifices 20 and 21 and a pressure valve chamber 24 associated With the orifice 22. The pressure-valve chamber communicates with the noisereducing unit by way of the pressure passage 25 which is likewise formed between the channel plate 11 and the metal plate 6. The orifices 20 and 21 serve both to supply suction gas through passages in the valve plate 1 and to introduce the suction gas into the cylinder 2 by way of the valve plate. The pressure gas is discharged from the noise-reducing unit through a pipe 26.
The middle plate 6 has at its edge tabs 27, which are bent over to one side, alternating therewith, tabs 28 bent over to the other side. The remaining sheet- metal parts 8, 10, 11, 13 and 15, contain slots 29 adapted to receive the tabs 27 and 28. For assembling the component 3, the prepared sheet- metal parts 8, 10, 11, 13 and 15 are simply pushed on to the middle plate 6 from both sides, their positions being accurately defined by the tabs 27 and 28 and the slots 29. The parts are then held together by the application of light pressure and passed through a solder ing furnace and soldered together, a very stable component 3 then resulting.
We claim:
1. A noise reducing assembly for a refrigeration unit of the hermetically sealed type in which the interior thereof is under subatmospheric pressure during operation of the unit, comprising, a compressor, first nnperforated wall means forming a noise reducing chamber for receiving a refrigerant gas exhausted by said compressor, second unperforated wall means in spaced relation to said first wall means forming an outer insulating chamber for said noise reducing chamber, a gas substantially statically contained in said outer chamber, said second wall means being soldered to said first wall means and said gas being a protective gas of the type used for soldering.
2. A noise reducing assembly for a refrigeration unit of the hermetically sealed type in which the interior there-, of is under subatrnospheric pressure during operation of the unit, comprising, a compressor, first unperforated wall means forming a noise reducing chamber for receiving a refrigerant gas exhausted by said compressor, second wall means in spaced relation to said first wall means forming an outer insulating chamber for said noise reducing chamher, a refrigerant gas substantially statically contained in said outer chamber, said second wall means having an opening formed therein for admitting a refrigerant gas to said outer chamber.
References Cited MARTIN P. SCHWADRON, Primary Examiner I. C. COHEN, Assistant Examiner U.S. Cl. X.R. 62-296; 417-902
US32469*[A 1968-03-16 1969-08-04 Hermetically enclosed small refrigerating machine Expired - Lifetime US3664769A (en)

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DE1601860A DE1601860C3 (en) 1968-03-16 1968-03-16 Hermetically sealed small refrigeration machine

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BR (1) BR6907198D0 (en)
DE (1) DE1601860C3 (en)
ES (1) ES364853A1 (en)
FR (1) FR2004059A1 (en)
GB (1) GB1246038A (en)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4061444A (en) * 1976-07-30 1977-12-06 Lennox Industries, Inc. Compressor muffling arrangement
US4371319A (en) * 1979-07-13 1983-02-01 Hitachi, Ltd. Hermetic motor compressor
US4431383A (en) * 1978-06-08 1984-02-14 Robert Bosch Gmbh Motor compressor for refrigerators
US4573880A (en) * 1982-09-02 1986-03-04 Sanyo Electric Co., Ltd. Hermetically sealed motor compressor
US4782858A (en) * 1984-11-29 1988-11-08 Kabushiki Kaisha Toshiba Valve cover for a compressor
US6012908A (en) * 1996-01-23 2000-01-11 Matsushita Refrigeration Company Electrically operated seal compressor having a refrigerant flow branch tube with a chamber disposed in the vicinity of a suction port
SG105449A1 (en) * 1995-09-29 2004-08-27 Matsushita Refrigeration Electrically-operated sealed compressor
WO2006092771A1 (en) * 2005-03-03 2006-09-08 Arcelik Anonim Sirketi A compressor
US20070264137A1 (en) * 2006-05-10 2007-11-15 Samsung Gwangju Electronics Co., Ltd. Hermetic compressor

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR0143182B1 (en) * 1994-04-29 1998-08-01 김광호 Compressor
DK172128B1 (en) † 1995-07-06 1997-11-17 Danfoss As Compressor with control electronics
JPH10238463A (en) * 1997-02-25 1998-09-08 Toyota Autom Loom Works Ltd Compressor

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4061444A (en) * 1976-07-30 1977-12-06 Lennox Industries, Inc. Compressor muffling arrangement
US4431383A (en) * 1978-06-08 1984-02-14 Robert Bosch Gmbh Motor compressor for refrigerators
US4371319A (en) * 1979-07-13 1983-02-01 Hitachi, Ltd. Hermetic motor compressor
US4573880A (en) * 1982-09-02 1986-03-04 Sanyo Electric Co., Ltd. Hermetically sealed motor compressor
US4782858A (en) * 1984-11-29 1988-11-08 Kabushiki Kaisha Toshiba Valve cover for a compressor
US6206655B1 (en) 1995-09-29 2001-03-27 Matsushita Refrigeration Company Electrically-operated sealed compressor
SG105449A1 (en) * 1995-09-29 2004-08-27 Matsushita Refrigeration Electrically-operated sealed compressor
US6012908A (en) * 1996-01-23 2000-01-11 Matsushita Refrigeration Company Electrically operated seal compressor having a refrigerant flow branch tube with a chamber disposed in the vicinity of a suction port
WO2006092771A1 (en) * 2005-03-03 2006-09-08 Arcelik Anonim Sirketi A compressor
US20070264137A1 (en) * 2006-05-10 2007-11-15 Samsung Gwangju Electronics Co., Ltd. Hermetic compressor

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Publication number Publication date
ES364853A1 (en) 1971-01-01
DE1601860C3 (en) 1974-05-22
DE1601860B2 (en) 1973-10-25
GB1246038A (en) 1971-09-15
DE1601860A1 (en) 1971-12-23
FR2004059A1 (en) 1969-11-21
BR6907198D0 (en) 1973-02-08

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