# US 12,601,350 B2 · Compressor and refrigeration cycle apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,601,350 B2 - Document ID: US12601350B2 - Status: Granted - Kind: B2 - Application number: 18/863,383 - Filed: 2022-08-04 - Published: 2025-10-09 - Granted: 2026-04-14 - Earliest claimed: 2022-08-04 - Assignees: Mitsubishi Electric Corporation - Applicants: Mitsubishi Electric Corporation - Inventors: Akikazu Izumi; Naohisa Gomae - Web page: https://patentgrep.com/patent/US12601350B2 ## CPC - F04C 23/008: {Hermetic pumps} - F04C 18/356: with vanes reciprocating with respect to the outer member - F04C 23/00: Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids (F04C25/00 takes precedence) - F04C 23/001: {of similar working principle} - F04C 29/00: Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00 - F04C: ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS (engines F03C); ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS ## Abstract A compressor includes: a hermetically sealed container; an electric motor; a low-stage compression mechanism unit; a high-stage compression mechanism unit; and an intermediate partition plate. The high-stage compression mechanism unit includes a high-stage cylinder block, a high-stage rolling piston, a high-stage vane configured to partition, along with the high-stage rolling piston, an internal space of the high-stage cylinder block into a high-stage suction chamber and a high-stage compression chamber, and a high-stage refrigerant supply passage through which compressed refrigerant is discharged, the high-stage refrigerant supply being surrounded by a high-stage bearing and a high-stage discharge muffler. A high-stage back pressure chamber is separate from an internal space of the hermetically sealed container, and communicates with the high-stage refrigerant supply passage, the high-stage back pressure chamber being surrounded by the high-stage cylinder block, the high-stage bearing, the intermediate partition plate, and the high-stage vane. ## Claims ### Claim 1 A compressor comprising: a hermetically sealed container; an electric motor; a low-stage compression mechanism unit driven by a crankshaft fitted into the electric motor and configured to compress low-pressure refrigerant to intermediate pressure; a high-stage compression mechanism unit driven by the crankshaft and configured to compress intermediate-pressure refrigerant discharged by the low-stage compression mechanism unit to high pressure; and an intermediate partition plate provided between the low-stage compression mechanism unit and the high-stage compression mechanism unit, the electric motor, the low-stage compression mechanism unit, the high-stage compression mechanism unit, and the intermediate partition plate being accommodated in an internal space of the hermetically sealed container, the high-stage compression mechanism unit including a high-stage cylinder block with a cylindrical shape, a high-stage rolling piston located in an internal space of the high-stage cylinder block, a high-stage vane located in the high-stage cylinder block such that the high-stage vane is slidable in a radial direction of the high-stage cylinder block, the high-stage vane being configured to partition, along with the high-stage rolling piston, the internal space of the high-stage cylinder block into a high-stage suction chamber into which refrigerant is sucked and a high-stage compression chamber in which refrigerant is compressed, and a high-stage refrigerant supply passage serving as a path through which refrigerant compressed in the high-stage compression chamber is discharged to a space external to the hermetically sealed container, the high-stage refrigerant supply passage being a space surrounded by a high-stage bearing and a high-stage discharge muffler, the high-stage bearing supporting the crankshaft and being adjacent to the high-stage cylinder block in an axial direction of the high-stage cylinder block, the high-stage discharge muffler being adjacent to the high-stage bearing in an axial direction of the high-stage cylinder block, the high-stage cylinder block including a high-stage back pressure chamber, the high-stage back pressure chamber being a space surrounded by an outer circumferential surface of the high-stage cylinder block, the high-stage bearing, the intermediate partition plate, and the high-stage vane, the high-stage back pressure chamber being a space separate from the internal space of the hermetically sealed container, and communicating with the high-stage refrigerant supply passage, in the high-stage bearing, a high-stage through hole being formed through which the high-stage back pressure chamber and the high-stage refrigerant supply passage communicate with each other, and in the high-stage bearing, a high-stage suction hole being formed and a tip end of a refrigerant suction pipe being inserted into the high-stage suction hole, wherein the low-stage compression mechanism unit, the high-stage compression mechanism unit, and the intermediate partition plate are layered from the bottom of the compressor in the order of the high-stage compression mechanism unit, the intermediate partition plate, and the low-stage compression mechanism unit. ### Claim 2 (depends on 1) The compressor of claim 1, wherein in the high-stage bearing, a high-stage through hole is formed through which the high-stage back pressure chamber and the high-stage refrigerant supply passage communicate with each other. ### Claim 3 (depends on 1) The compressor of claim 1, comprising: a high-stage spring hole formed in the high-stage cylinder block such that an outer circumferential surface of the high-stage cylinder block and the high-stage back pressure chamber communicate with each other; and a high-stage plug provided at a portion of the high-stage spring hole, the portion being in contact with an outer circumferential surface of the high-stage cylinder block, such that the high-stage plug closes the high-stage spring hole. ### Claim 4 (depends on 3) The compressor of claim 3, wherein a high-stage female screw portion is formed in the high-stage spring hole, a high-stage male screw portion is formed in the high-stage plug, and the high-stage plug is screwed into the high-stage spring hole. ### Claim 5 (depends on 1) A refrigeration cycle apparatus comprising: the compressor of claim 1; a condenser liquefying refrigerant discharged from the compressor; a pressure-reducing device configured to reduce a pressure of refrigerant delivered from the condenser; and an evaporator gasifying refrigerant delivered from the pressure-reducing device. ### Claim 6 A compressor comprising: a hermetically sealed container; an electric motor; a low-stage compression mechanism unit driven by a crankshaft fitted into the electric motor and configured to compress low-pressure refrigerant to intermediate pressure; a high-stage compression mechanism unit driven by the crankshaft and configured to compress intermediate-pressure refrigerant discharged by the low-stage compression mechanism unit to high pressure; and an intermediate partition plate provided between the low-stage compression mechanism unit and the high-stage compression mechanism unit, the electric motor, the low-stage compression mechanism unit, the high-stage compression mechanism unit, and the intermediate partition plate being accommodated in an internal space of the hermetically sealed container, wherein the high-stage compression mechanism unit includes a high-stage cylinder block with a cylindrical shape, a high-stage rolling piston located in an internal space of the high-stage cylinder block, a high-stage vane located in the high-stage cylinder block such that the high-stage vane is slidable in a radial direction of the high-stage cylinder block, the high-stage vane being configured to partition, along with the high-stage rolling piston, the internal space of the high-stage cylinder block into a high-stage suction chamber into which refrigerant is sucked and a high-stage compression chamber in which refrigerant is compressed, and a high-stage refrigerant supply passage serving as a path through which refrigerant compressed in the high-stage compression chamber is discharged to a space external to the hermetically sealed container, the high-stage refrigerant supply passage being a space surrounded by a high-stage bearing and a high-stage discharge muffler, the high-stage bearing supporting the crankshaft and being adjacent to the high-stage cylinder block in an axial direction of the high-stage cylinder block, the high-stage discharge muffler being adjacent to the high-stage bearing in an axial direction of the high-stage cylinder block, the high-stage cylinder block includes a high-stage back pressure chamber, the high-stage back pressure chamber being a space surrounded by an outer circumferential surface of the high-stage cylinder block, the high-stage bearing, the intermediate partition plate, and the high-stage vane, the high-stage back pressure chamber is a space separate from the internal space of the hermetically sealed container, and communicates with the high-stage refrigerant supply passage, in the high-stage bearing, a high-stage suction hole is formed and a tip end of a refrigerant suction pipe is inserted into the high-stage suction hole, the low-stage compression mechanism unit includes a low-stage cylinder block with a cylindrical shape, a low-stage rolling piston located in an internal space of the low-stage cylinder block, and a low-stage vane located in the low-stage cylinder block such that the low-stage vane is slidable in a radial direction of the low-stage cylinder block, the low-stage vane being configured to partition, along with the low-stage rolling piston, the internal space of the low-stage cylinder block into a low-stage suction chamber into which refrigerant is sucked by increasing a volume of the low-stage suction chamber and a low-stage compression chamber in which refrigerant is compressed by decreasing a volume of the low-stage compression chamber, the low-stage cylinder block includes a low-stage back pressure chamber, the low-stage back pressure chamber being a space surrounded by an outer circumferential surface of the low-stage cylinder block, a low-stage bearing, the intermediate partition plate, and the low-stage vane, the low-stage bearing supporting the crankshaft and being adjacent to the low-stage cylinder block in an axial direction of the low-stage cylinder block, and the low-stage back pressure chamber is a space separate from the internal space of the hermetically sealed container, and communicates with the high-stage refrigerant supply passage-not via the internal space of the hermetically sealed container, wherein the low-stage compression mechanism unit, the high-stage compression mechanism unit, and the intermediate partition plate are layered from the bottom of the compressor in the order of the high-stage compression mechanism unit, the intermediate partition plate, and the low-stage compression mechanism unit. ### Claim 7 (depends on 6) The compressor of claim 6, wherein in the intermediate partition plate, a low-stage through hole is formed through which the low-stage back pressure chamber and the high-stage refrigerant supply passage communicate with each other. ### Claim 8 (depends on 6) The compressor of claim 6, comprising: a low-stage spring hole formed in the low-stage cylinder block such that an outer circumferential surface of the low-stage cylinder block and the low-stage back pressure chamber communicate with each other; and a low-stage plug provided at a portion of the low-stage spring hole, the portion being in contact with an outer circumferential surface of the low-stage cylinder block, such that the low-stage plug closes the low-stage spring hole. ### Claim 9 (depends on 8) The compressor of claim 8, wherein a low-stage female screw portion is formed in the low-stage spring hole, a low-stage male screw portion is formed in the low-stage plug, and the low-stage plug is screwed into the low-stage spring hole. ### Claim 10 (depends on 6) The compressor of claim 6, wherein a refrigerant discharge pipe discharges refrigerant from the low-stage compression mechanism unit, and the refrigerant suction pipe receives refrigerant from the refrigerant discharge pipe. ### Claim 11 (depends on 6) The compressor of claim 6, wherein the bottom of the compressor is a side of the compressor adjacent to a base to which the compressor is fixed.