Muffler for rotary compressor

Details Muffler for rotary compressor Muffler for rotary compressor

1999-09-07

2001-09-11

Denion, Thomas (Department: 3748)

Rotary expansible chamber devices

Working member has planetary or planetating movement

With relatively movable partition member

C418S181000

Reexamination Certificate

active

06287098

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a rotary compressor, and more particularly, to a muffler for attenuating a noise generated in operation of a rotary compressor.
2. Background of the Related Art
The compressor for compressing air or gas to a required pressure is used in an air conditioner or the like for compressing a refrigerant gas to a required pressure.
A related art rotary compressor will be explained with reference to
FIGS. 1 and 2
.
The related art rotary compressor is provided with a hermetic case
1
having a suction pipe
16
for drawing refrigerant and a discharge pipe
5
for discharging the compressed refrigerant, both connected thereto, a driving unit
6
in the case
1
for providing a rotating force, and a compression unit
10
for compressing gas. The driving unit
6
has a stator
2
and a rotor
3
of a motor mounted on an upper portion in the case
1
. The rotor
3
is coupled to a shaft
4
for transmission of a rotating power to the compression unit
10
. The rotor
3
has an eccentric portion
4
a
at a lower portion thereof. The compression unit
10
has a compression chamber ‘C’ enclosed by a cylinder
11
forming a wall of the compression chamber ‘C’, and a main bearing
14
and a supplementary bearing
15
mounted at an upper side and a lower side of the compression chamber ‘C’ respectively. The compression chamber ‘C’ has the suction pipe
16
connected thereto for receiving refrigerant from outside of the compression chamber ‘C’. The cylinder
11
and the main bearing
14
have a discharge opening
11
a
and a discharge passage
14
b
formed therein respectively for discharging refrigerant, which discharge passage
14
b
is opened/closed by a valve(not shown). In the meantime, the eccentric portion
4
a
of the shaft is mounted in the compression chamber ‘C’, i.e., inside of the cylinder
11
. There is a roller
12
fitted to an outside of the eccentric portion
4
a
for making a compression action as the eccentric portion
4
a
keeps making contact with an inside surface of the cylinder
11
following rotation of the eccentric portion
4
a
. And, there is a vane
13
mounted in the cylinder
11
to be always in contact with an outside of the roller
12
biased by a spring for dividing the compression chamber ‘C’ into a high pressure portion and a low pressure portion. There is a muffler
20
above the main bearing
14
for attenuation of noise, which has a muffler discharge opening
21
for discharging a compressed gas received from a cylinder discharge opening
11
a
to an inside of the case
1
.
The muffler will be explained with reference to
FIGS. 3A and 3B
.
The muffler
20
in a form of a cap has a boss hole
22
for passing a boss portion
14
a
of the main bearing
14
, and recessed bolt fixing parts
23
in an outer circumference thereof for fastening the muffler
20
to the main bearing
14
. The muffler
20
has a muffler discharge opening
21
for discharging the compressed gas flowed into the muffler
20
, formed in outer periphery spaced from the boss hole
22
.
The operation of the related art rotary compressor will be explained with reference to
FIGS. 1 and 2
.
Upon starting the rotary compressor, the rotor
3
of the motor is rotated, to rotate the eccentric portion
4
a
of the shaft, eccentrically rotating the roller
12
inside of the cylinder
11
in a state the roller
12
is in contact with the vane
13
. The eccentric rotation of the roller
12
reduces a volume of the compression chamber ‘C’, compressing low pressure refrigerant flowed into the compression chamber ‘C’ through the suction pipe
16
to a required pressure. The compressed high pressure refrigerant is discharged into the muffler
20
above the main bearing
14
through the cylinder discharge opening
11
a
and the discharge passage
14
b
of the main bearing, following operation of the valve. The high pressure refrigerant thus discharged into the muffler
20
is discharged into an inside of the case
1
through the muffler discharge opening
21
. And the high pressure refrigerant discharged into inside of the case
1
is discharged outside of the rotary compressor through the discharge pipe
5
on top of the case
1
through gaps between the rotor
3
and the stator
2
or the case
1
and the stator
2
.
FIG. 4
illustrates a pressure distribution in the muffler calculated according to a numerical analysis method, and
FIG. 5
illustrates a kinetic turbulent energy distribution calculated according to the numerical analysis method, referring to which a flow state of the compressed refrigerant inside of the muffler
20
will be explained.
As can be known from
FIGS. 4 and 5
, though there is a small pressure distribution variation in overall in the muffler
20
, a kinetic turbulent energy distribution exhibited has a great variation. Though the pressure affects a performance of the compressor, the kinetic turbulent energy affects to a noise of the compressor. This is because the kinetic turbulent energy is a velocity energy which is a square of a velocity, and, though a fluid noise is functions of pressure variation, speed variation, and density variation, the pressure variation and the density variation affects to the noise little, but the velocity variation is proportional to the noise generation, mostly.
That is, as shown in
FIG. 5
, it can be known that, though there is a slight variation of kinetic turbulent energy around the boss hole
22
in the related art muffler
20
, there is a great variation of kinetic turbulent energy as it goes to an outer circumference of the muffler where the muffler discharge opening is positioned, that increases the noise.
The reason why there is a great variation of the kinetic turbulent energy in the vicinity of the muffler discharge opening
21
will be explained.
The gas compressed in the compression chamber ‘C’ is discharged from the compression chamber ‘C’ to the muffler
20
in a turbulent state at a fixed average speed. Therefore, the gas discharged into the muffler
20
has a centrifugal force exerted thereon from the average speed and a discharge speed, to form a main flow at an outer circumference of the muffler
20
, with an increased gas speed. That is, as the compressed gas flows from an inner circumference to the outer circumference of the muffler
20
, a gas flow speed is increased by the inertia until the gas is discharged through the muffler discharge opening
21
formed in the vicinity of the outer circumference of the muffler
20
, that causes much noise.
Therefore, because the refrigerant flowed in the muffler has not an even kinetic turbulent energy distribution and is discharged outside of the muffler
20
through the muffler discharge opening
21
without consumption of much of the velocity energy, the refrigerant is involved in little amount of a pressure fluctuation and a speed reduced in the muffler
20
. Thus, the related art muffler has a poor noise reduction performance, and shows a directional noise generation pattern according to a position of the muffler discharge opening.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a muffler that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a muffler for a rotary compressor which can improve a noise attenuation function.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, the rotary compressor including a main bearing having a discharge passage for discharging compressed gas and a b

Affiliated with

Also associated with

Rating

Muffler for rotary compressor does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Muffler for rotary compressor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Muffler for rotary compressor will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2523211