Heat pump compressor including liquid crystal polymer insulating material

Patent metadata

Field	Value
Publication number	US-9915465-B2
Application number	US-201515300306-A
Country	US
Kind code	B2
Filing date	Mar 6, 2015
Priority date	Apr 10, 2014
Publication date	Mar 13, 2018
Grant date	Mar 13, 2018

Abstract

An insulating material that tends not to hydrolyze is used to thereby provide a heat pump apparatus having long-term reliability. An electric motor of a compressor is fixed to a sealed container and includes a stator around which a winding wire is wound through intermediation of an insulating material, and a rotor surrounded by the stator. The insulating material is a wholly aromatic liquid crystal polyester (LCP) having a molecular main chain constituted by a monomer including p-hydroxybenzoic acid (PHB) as an essential monomer and a monomer solely including benzene-ring as another monomer via an ester bond. The refrigerating machine oil has a saturated water content of 2% or less at 40 degrees C., a relative humidity of 80%, for 24 Hr. To suppress the explosive decomposition reaction of ethylene-based fluorohydrocarbon, a flame retardant is used to generate chemical species that complement active radicals that cause the decomposition reaction.

First claim

The invention claimed is:

1. A heat pump apparatus comprising:
a compressor;
a condenser;
an expansion mechanism; and
an evaporator,
the compressor, the condenser, the expansion mechanism, and the evaporator being configured to perform a refrigeration cycle,

the heat pump apparatus being configured to perform heat transfer in the condenser or the evaporator,
the compressor including
a sealed container,
a compression mechanism mounted inside the sealed container, and
an electric motor configured to rotatively drive the compression mechanism,
the compression mechanism being configured to compress a refrigerant, and to be lubricated by a refrigerating machine oil,

the electric motor including
a stator fixed to the sealed container, with a winding wire being wound around the stator through intermediation of an insulating material, and
a rotor surrounded by the stator,

wherein the insulating material comprises
a wholly aromatic liquid crystal polyester (LCP) having a molecular main chain constituted by a monomer including p-hydroxybenzoic acid (PHB) as an essential monomer and a monomer solely including benzene-ring as another monomer via an ester bond,

and
wherein the refrigerant comprises
any one of a single-component substance composed of difluoromethane (HFC-32), propylene-based fluorohydrocarbon (HFO-1234yf), or ethylene-based hydrogen fluoride; a multi-component substance composed of two or more of difluoromethane (HFC-32), propylene-based fluorohydrocarbon (HFO-1234yf), and ethylene-based hydrogen fluoride; and a multi-component substance containing a mixture of difluoromethane (HFC-32) and ethylene-based hydrogen fluoride, and

a ratio of the ethylene-based hydrogen fluoride to the difluoromethane (HFC-32) is less than 60 wt %.

2. The heat pump apparatus of claim 1 , wherein the wholly aromatic liquid crystal polyester (LCP) as the insulating material has
a latent heat of crystallization of 10 J/g or less measured by a differential scanning calorimeter (DSC).

3. The heat pump apparatus of claim 1 , wherein the insulating material comprises
a wholly aromatic liquid crystal polyester (LCP) synthesized by polycondensation of two or more monomers in total that are p-hydroxybenzoic acid (PHB) as an essential monomer component having an ester bond, and at least one additive component selected from five components of 4,4′-biphenol (BP), hydroquinone (HQ), terephthalic acid (TPA), isophthalic acid (IPA), and 6-hydroxy-2-naphthoic acid (BONG).

4. The heat pump apparatus of claim 1 , wherein the refrigerating machine oil comprises
a single-component substance or a multi-component substance composed of at least one of an ester-based oil, an ether-based oil, a glycol-based oil, an alkylbenzene-based oil, a poly-α-olefin-based oil, a polyvinyl ether-based oil, a fluorine-based oil, a naphthene-based mineral oil, and a paraffin-based mineral oil.

5. The heat pump apparatus of claim 1 , wherein the ethylene-based hydrogen fluoride comprises
a single-component substance or a multi-component substance composed of at least one of trans-1,2-difluoroethylene (R1132(E)), fluoroethylene (R1141), cis-1,2-difluoroethylene (R1132(Z)), 1,1-difluoroethylene (R1132a), and 1,1,2-trifluoroethylene (R1123).

6. The heat pump apparatus of claim 1 , wherein a flame retardant that inhibits a decomposition reaction of the refrigerant is contained in at least one of the refrigerating machine oil, a slidable part of the compressor, the insulating material, a surface-coating oil of the winding wire, a coating of a lead wire connected to the winding wire, and a cluster connected to the lead wire.

7. The heat pump apparatus of claim 6 , wherein the flame retardant comprises
at least one of a halogen-based flame retardant, a phosphorus-based flame retardant, and an antimony compound.

8. The heat pump apparatus of claim 1 , wherein the refrigerating machine oil has a saturated water content of 0.2% or less.

9. A heat pump apparatus comprising:
a compressor;
a condenser;
an expansion mechanism; and
an evaporator,
the compressor, the condenser, the expansion mechanism, and the evaporator being configured to perform a refrigeration cycle,

the heat pump apparatus being configured to perform heat transfer in the condenser or the evaporator,
the compressor including
a sealed container,
a compression mechanism mounted inside the sealed container, and
an electric motor configured to rotatively drive the compression mechanism,
the compression mechanism being configured to compress a refrigerant, and to be lubricated by a refrigerating machine oil,

the electric motor including
a stator fixed to the sealed container, with a winding wire being wound around the stator through intermediation of an insulating material, and
a rotor surrounded by the stator,

wherein the insulating material comprises
a wholly aromatic liquid crystal polyester (LCP) synthesized by polycondensation of two or more monomers in total that are p-hydroxybenzoic acid (PHB) as an essential monomer, and at least two additive components selected from five components of 4,4′-biphenol (BP), hydroquinone (HQ), terephthalic acid (TPA), isophthalic acid (IPA), and 6-hydroxy-2-naphthoic acid (BONG) or at least one additive component selected from three components of hydroquinone (HQ), terephthalic acid (TPA), isophthalic acid (IPA), and

wherein the refrigerating machine oil has a saturated water content of 2% or less at 40 degrees C. and a relative humidity of 80%, for 24 Hr.

10. The heat pump apparatus of claim 9 , wherein the refrigerating machine oil comprises
a single-component substance or a multi-component substance composed of at least one of an ester-based oil, an ether-based oil, a glycol-based oil, an alkylbenzene-based oil, a poly-α-olefin-based oil, a polyvinyl ether-based oil, a fluorine-based oil, a naphthene-based mineral oil, and a paraffin-based mineral oil.

11. The heat pump apparatus of claim 9 , wherein the refrigerant comprises
any one of a single-component substance composed of difluoromethane (HFC-32), propylene-based fluorohydrocarbon (HFO-1234yf), or ethylene-based hydrogen fluoride; a multi-component substance composed of two or more of difluoromethane (HFC-32), propylene-based fluorohydrocarbon (HFO-1234yf), and ethylene-based hydrogen fluoride; and a multi-component substance containing a mixture of difluoromethane (HFC-32) and ethylene-based hydrogen fluoride, and
a ratio of the ethylene-based hydrogen fluoride to the difluoromethane (HFC-32) is less than 60 wt %.

12. The heat pump apparatus of claim 9 , wherein the ethylene-based hydrogen fluoride comprises
a single-component substance or a multi-component substance composed of at least one of trans-1,2-difluoroethylene (R1132(E)), fluoroethylene (R1141), cis-1,2-difluoroethylene (R1132(Z)), 1,1-difluoroethylene (R1132a), and 1,1,2-trifluoroethylene (R1123).

13. The heat pump apparatus of claim 1 , wherein a flame retardant that inhibits a decomposition reaction of the refrigerant is contained in at least one of the refrigerating machine oil, a slidable part of the compressor, the insulating material, a surface-coating oil of the winding wire, a coating of a lead wire connected to the winding wire, and a cluster connected to the lead wire.

14. The heat pump apparatus of claim 13 , wherein the flame retardant comprises
at least one of a halogen-based flame retardant, a phosphorus-based flame retardant, and an antimony compound.

15. The heat pump apparatus of claim 9 , wherein the refrigerating machine oil has a saturated water content of 0.2% or le

Assignees

• Mitsubishi Electric Corp

Inventors

• Matsunaga Noriaki
• Ogasawara Shinobu
• Kageyama Takeharu
• Toyama Satoru
• Mizuno Kota
• Hirakawa Yutaka

Classifications

• F04C29/0085

  Prime movers · CPC title

• 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 · CPC title

• F04C18/356

  with vanes reciprocating with respect to the outer member · CPC title

• F04C2210/263

  HFO1234YF · CPC title

• F25D23/065 Primary

  Details · CPC title