JPH03213681A - Enclosed type compressor - Google Patents

Abstract

PURPOSE:To reduce noise by providing a volume for preventing resonance on the way of a gas passage, in a compressor in which compressed gas is discharged from a first expansion chamber defined under a motor to the outside through a gas passage and a second expansion chamber defined over the motor. CONSTITUTION:When a motor 2 is driven, a rolling piston 6 is eccentrically rotationally moved in the cylinder chamber 12 of a cylinder block 7 through a crankshaft 4, and gas sucked from a suction pipe 20 is compressed and entered into a first expansion chamber 28 under the motor 2 through the discharge port 22 provided on an upper bearing 8 and a discharge muffler chamber 27. Nextly, the gas is discharged outside through the gas passage formed in the stator of the motor 2, a second expansion chamber 15 over the motor 2, and a discharge pipe 16. In this case, volume 31 for preventing resonance is formed on the way of a gas passage 30. Hereby, exciting force in the up and down direction applied on the rotating body consisting of the crankshaft 4 snd the rotor 2b of the motor 2 is decreased, and noise is reduced.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a hermetic compressor.

(Prior Art) An example of a conventional hermetic compressor is shown in FIGS. 4 and 5.

A motor 2 consisting of a stake 2a and a rotor 2b, and a rotary compression mechanism 3 rotationally driven by the motor 2 are disposed within the sealed casing 1.

A stator 2a of the motor 2 is fixed to the casing 1, and a rotor 2b is fixed to the upper part of the crankshaft 4.

The rolling compression mechanism 3 includes a rolling piston 6 fitted to a crank pin 5 of a crankshaft 4, a cylinder block 7 fixed to the casing 1, an upper bearing 8 that closes the upper end opening of the cylinder block 7, and a cylinder block. a lower bearing 9 that closes the lower end opening of the cylinder block 7; a blade 10 that is supported by the cylinder block 7 so as to be freely retractable;
It consists of a spring 11 and the like disposed behind the blade 10 to push it forward.

A rolling piston 6 is placed in a cylinder chamber 12 bounded by a cylinder block 7, an upper bearing 8 and a lower bearing 9.
The tip of the blade 10 is brought into contact with the outer peripheral surface of the rolling piston 6, thereby defining a suction chamber 13 on one side of the blade 10 and a compression chamber 14 on the other side.

The crankshaft 4 is supported by an upper bearing 8 and a lower bearing 9, respectively.

When the crankshaft 4 is rotationally driven by the motor 2, a rolling piston 6 fitted to the crank pin 5
rotates eccentrically in the direction of the arrow within the cylinder chamber 12 while slidingly contacting the inner circumferential surface of the cylinder block 7 . At the same time, gas is sucked into the suction chamber 13 from the suction pipe 20, and the gas in the compression chamber 14 is compressed.

The compressed gas is discharged through a discharge boat 2 bored in the upper bearing 8.
2 and pushes up a discharge valve (not shown) to enter the discharge muffler chamber 27 bounded by the upper bearing 8 and the cover 26 covering the upper surface thereof, and its pulsating components are removed.

Next, the pulsating component is further removed by entering a second expansion chamber 28 limited below the motor 2 through a hole (not shown) formed in the cover 26 and expanding. It then enters the second expansion chamber 15 bounded by the upper part of the motor 2 through the air gear between the stator 2a and the rotor 2b and the gas passage 29 formed between the stator 2a and the casing 1, where it again enters. By expanding, the pulsating component is further removed, and then it is discharged to the outside through the discharge pipe 16.

Lubricating oil 17 is stored in the inner bottom of the casing 1, and this lubricating oil 17 is pumped up by a centrifugal oil pump 18 built into the crankshaft 4 and sent to the crankshaft via an oil supply passage 19 bored in the crankshaft 4. 4
The sliding surfaces between the upper bearing 8 and the lower bearing 9, the sliding surfaces between the crank pin 5 and the rolling piston 6, the sliding surfaces between the rolling piston 6 and the cylinder block 7, and the like are supplied with oil.

(Problems to be Solved by the Invention) In the conventional hermetic compressor described above, the first expansion chamber 28
Since a phase difference occurs between the pulsation of gas in the second expansion chamber 15 and the pulsation of gas in the second expansion chamber 15, the rotating body consisting of the crankshaft 4 and the rotor 2b of the motor 2 There was a problem in that the crankshaft 4 intermittently collided with the upper bearing 8 and the lower bearing 9 due to the vibration caused by the vertical vibration, which generated noise.

(Means for Solving the Problems) The present invention was invented to solve the above problems, and its gist is that a compression mechanism and a motor for driving this compression mechanism are installed in a cloth-closed casing. is built in, and the gas discharged from the compression mechanism is passed through a first expansion chamber limited below the motor, a gas passage formed in the stator of the motor, and a second expansion chamber limited above the motor.
The hermetic compressor discharges gas to the outside through an expansion chamber, characterized in that a resonance prevention volume is formed in the middle of the gas passage.

Small diameter holes forming the gas passage and large diameter holes forming the resonance prevention volume are alternately bored at a predetermined pitch in a large number of plates constituting the stator of the motor, and a predetermined number of these plates are formed. The formation of the resonance prevention volume can be avoided by stacking the layers one after the other by shifting them by the predetermined pitch.

(Function) Since the present invention has the above configuration, the differential pressure between the compartments due to the phase difference between the pulsation of gas in the first expansion chamber and the pulsation of gas in the second expansion chamber is The pressure is equalized by the gas passage, and resonance between the first expansion chamber and the second expansion chamber is prevented by a resonance prevention volume formed in the middle of the gas passage. The vertical excitation force that acts on the is reduced.

(Example) One embodiment of the invention is shown in FIGS. 1 and 2.

A gas passage 30 that communicates the first expansion chamber 28 and the second expansion chamber 15 is formed in the stator 2a of the motor 2, and a resonance prevention volume 31 is formed in the middle of the gas passage 30. The volume of the resonance prevention volume 31 is determined according to the resonance frequencies of the first expansion chamber 28 and the second expansion chamber 15.

As shown in FIG.
Small diameter holes 32 forming a resonance prevention volume 31 and large diameter holes 33 forming a resonance prevention volume 31 are alternately bored at a predetermined pitch p in the circumferential direction, and these plates 2al are formed as shown in FIG. The gas passage 30 and the anti-resonance volume 31 can be formed by stacking a predetermined number of sheets, that is, the number of sheets constituting the vertical height h required for the volume 31, shifted by a predetermined pitch p. The capacity of the volume 31 can be easily changed by adjusting the number of layers stacked at the same pitch.

The rest of the structure is similar to the conventional one shown in FIGS. 4 and 5, and corresponding members are given the same reference numerals.

During operation of the hermetic compressor, the gas discharged into the first expansion chamber 28 passes through the gas passage 30 formed in the stator 2a of the motor 2 and the resonance prevention volume 31, and then passes through the second expansion chamber 28.
flows into the expansion chamber 15 , and the differential pressure between the two chambers based on the phase difference between the pulsation in the first expansion chamber 28 and the pulsation in the second expansion chamber 15 is equalized by the gas passage 30 At the same time, resonance between the first expansion chamber 28 and the second expansion chamber 15 is prevented by the resonance preventing polynym 31.

(Effects of the Invention) In the present invention, since resonance between the first expansion chamber and the second expansion chamber is prevented by the resonance prevention volume formed in the middle of the gas passage, the crankshaft and the rotor of the motor The vertical excitation force acting on the rotating body is reduced. As a result, noise generated by the crankshaft colliding with the upper bearing and the lower bearing can be prevented or suppressed.

Small diameter holes forming gas passages and large diameter holes forming resonance prevention volumes are alternately bored at a predetermined pitch in a large number of plates constituting the stator of the motor, and a predetermined number of these plates are drilled at the predetermined pitch. If they are stacked with a shift of only a certain amount, the gas passage and the anti-resonance volume can be easily formed, and the volume of the anti-resonance volume can be easily changed.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a longitudinal cross-sectional view showing one embodiment of the present invention, FIGS. 2 and 3 show other embodiments of the present invention, and FIG. 2 shows a structure of a stator of a motor. FIG. 3 is a sectional view taken along line mm in FIG. 2 showing the stator of the motor. 4 and 5 show an example of a conventional hermetic compressor, with FIG. 4 being a longitudinal cross-sectional view and FIG. 5 being a cross-sectional view taken along line V-V in FIG. 4. Sealed casing-1, compression mechanism 3, motor 2, stator 28, first expansion chamber-28, second expansion chamber 15
, gas passage-30, resonance prevention volume-31■2

Claims (2)

[Claims] (1) A compression mechanism and a motor for driving the compression mechanism are built into a sealed casing, and gas discharged from the compression mechanism is passed from a first expansion chamber limited below the motor to the stator of the motor. The hermetic compressor discharges the gas to the outside through a gas passage and a second expansion chamber limited above the motor, characterized in that a resonance prevention volume is formed in the middle of the gas passage. Hermetic compressor. (2) Small-diameter holes forming the gas passage and large-diameter holes forming the resonance prevention volume are alternately bored at a predetermined pitch in a large number of plates constituting the stator of the motor, and these plates 2. The hermetic compressor according to claim 1, wherein the resonance prevention volume is formed by stacking a predetermined number of sheets shifted by the predetermined pitch.