Compressor

Patent metadata

Field	Value
Publication number	US-2022106950-A1
Application number	US-202017420755-A
Country	US
Kind code	A1
Filing date	Mar 10, 2020
Priority date	Oct 1, 2019
Publication date	Apr 7, 2022
Grant date	—

Abstract

There is provided a compressor including: a piston that reciprocates inside a cylinder; a valve plate that closes an end portion of the cylinder; a connecting rod that supports the piston; a crankshaft that applies a rotating force to an end portion of the connecting rod; and a crankcase that rotatably supports the crankshaft. The piston is an oscillating piston that reciprocates while oscillating inside the cylinder according to rotation of the crankshaft. An outer peripheral surface of the piston is a curved surface.

First claim

1 . A compressor comprising:
a piston that reciprocates inside a cylinder; a valve plate that closes an end portion of the cylinder; a connecting rod that supports the piston; a crankshaft that applies a rotating force to an end portion of the connecting rod; and a crankcase that rotatably supports the crankshaft, wherein the piston is an oscillating piston that reciprocates while oscillating inside the cylinder according to rotation of the crankshaft, and an outer peripheral surface of the piston is a curved surface.

2 . The compressor according to claim 1 ,
wherein the outer peripheral surface of the piston comes into contact with an inner peripheral surface of the cylinder during reciprocating motion and slides against the inner peripheral surface.

3 . The compressor according to claim 1 ,
wherein the piston is fixed to or integrated with the connecting rod.

4 . The compressor according to claim 1 ,
wherein the piston is made of a resin having wear resistance at a location where the outer peripheral surface comes into contact with an inner peripheral surface of the cylinder.

5 . The compressor according to claim 4 ,
wherein a coefficient of thermal expansion of the resin is smaller in a direction perpendicular to a reciprocating direction than in the reciprocating direction in a state where the piston is at a top dead center.

6 . The compressor according to claim 1 ,
wherein a diameter of a spherical outer peripheral surface of the piston is larger in a direction perpendicular to a reciprocating direction than in the reciprocating direction in a state where the piston is at a top dead center.

7 . The compressor according to claim 4 ,
wherein the resin is PTFE, PPS, PES, a phenolic resin, a polyimide resin, a copna resin, or a mixture of these resins.

8 . The compressor according to claim 1 ,
wherein the piston is fastened to the connecting rod with screws, and a plurality of the screws are disposed in an oscillation direction of the connecting rod.

9 . The compressor according to claim 1 ,
wherein the piston is fastened to the connecting rod with a screw, and an outermost diameter of the screw is a diameter of 1/10 or less of an inner diameter of the cylinder.

10 . The compressor according to claim 1 ,
wherein a part or an entirety of the piston is made of aluminum, and the outer peripheral surface is lubricated with an oil during operation.

11 . The compressor according to claim 1 ,
wherein the piston includes an annular groove in the outer peripheral surface, and includes a piston ring, which seals a compressed gas, in the annular groove.

12 . The compressor according to claim 11 ,
wherein the curved surface is a spherical surface, and a center point of the spherical surface is disposed between planes obtained by extending upper and lower end surfaces of the annular groove.

13 . The compressor according to claim 11 ,
wherein the curved surface is a spherical surface, and a center point of the spherical surface is disposed on a plane obtained by extending a crankcase side surface of the annular groove.

14 . The compressor according to claim 1 ,
wherein the curved surface is a surface of a substantially perfect sphere.

15 . The compressor according to claim 1 ,
wherein the curved surface has a surface shape of a sphere having a diameter smaller than a diameter of the cylinder.

16 . The compressor according to claim 1 ,
wherein a cross section of the curved surface is a substantially oval, the cross section passing through a central axis of an inner diameter of the cylinder and being orthogonal to a rotation axis of the crankshaft.

Assignees

• Hitachi Industry Equipment Systems Co Ltd

Inventors

• Narisawa Nobuyuki
• Umeda Ken
• Goto Sho
• Suzuki Tatsuya

Classifications

• F04B53/143 Primary

  Sealing provided on the piston · CPC title

• F04B39/14

  Provisions for readily assembling or disassembling · CPC title

• F04B39/0022

  piston rods · CPC title

• F04B39/0005

  adaptations of pistons · CPC title

• F04B35/06 Primary

  Mobile combinations · CPC title