Pumps – Motor driven – Electric or magnetic motor
Reexamination Certificate
2001-02-08
2002-12-17
Freay, Charles G. (Department: 3746)
Pumps
Motor driven
Electric or magnetic motor
C417S312000, C417S902000, C181S403000, C181S200000
Reexamination Certificate
active
06494690
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a hermetic compressor, and more particularly to a hermetic compressor having an improved structure for reducing the noise generated during operation of the compressor.
2. Description of the Related Art
Generally, as shown in
FIG. 1
, a hermetic compressor includes a sealing case
1
, an electric drive portion
10
formed in the case
1
, and a compression portion
20
. The electric drive portion
10
generates a driving force that reciprocates linearly to compress a refrigerant in the compression portion
20
. The electric drive portion
10
includes a rotor
11
and a stator
12
.
The case
1
includes a lower shell
1
a
and an upper shell
1
b
. A rotary shaft
14
having an eccentric portion
13
is press fit on the rotor
11
. The compression portion
20
includes a cylinder
21
having a suction port
21
a
and a discharge port
21
b
, a piston
22
that linearly reciprocates within the cylinder
21
, and a connecting rod
23
disposed between the piston
22
and the eccentric portion
13
of the rotary shaft
14
. As the rotary shaft
14
rotates along with the rotor
11
, the piston
22
reciprocates within the cylinder
21
. The movement of the piston
22
causes the refrigerant to be repeatedly drawn in and discharged through the suction port
21
a
and the discharge port
21
b.
A compressor having the above structure is usually employed in household refrigerators, and its quality depends mainly on the following two factors: the compression efficiency; and how quiet the compressor is during operation. More specifically, as the compressor operates, various levels of cavity resonance are generated due to the temperature and pressure in the case
1
. When the cavity resonance equals the resonance frequency of the case
1
, it generates unpleasant sounds, and the compressor vibrates severely. It is evident that such vibration and noise from the compressor affect the quality of the refrigerator. More serious noise is produced from the upper portion of the upper shell
1
b
, which makes high-pitched, metallic, trembling sounds in the high frequency range of 3100 Hz to 3300 Hz. It is noise in this frequency range that has to be particularly controlled.
Because the resonance, which is the main source of the noise, is generated at various frequency ranges, it has been difficult to design a compressor that could prevent noise across a broad range, spanning from the cavity resonance range to resonance frequency range. Recently, the suggestion has been made to vary the thickness of the case
1
to vary the cavity resonance from the resonance frequency range. The suggestion, however, leads to problems, such as difficult and complex design of the compressor and a thicker case
1
.
SUMMARY OF THE INVENTION
The present invention has been made to overcome the above-mentioned problems of the related art. Accordingly, it is an object of the present invention to provide a hermetic compressor having an improved structure for reducing noise that is generated during operation of the compressor.
The above object is accomplished by providing a hermetic compressor including an electric drive portion, a compression portion and a casing. The electric drive portion has a rotor and a stator and generates a driving force to compress a refrigerant in the compression portion. The casing encloses the electric drive portion and the compression portion. The compressor further includes a unit process portion formed on an upper portion of the casing. The unit process portion is processed to have a circular or a polygonal shape from a front view. The unit process portion increases a rigidity of the casing, thereby reducing the amount of noise that is generated from the electric drive portion and the compression portion during an operation of the compressor.
REFERENCES:
patent: 2963113 (1960-12-01), Ayling
patent: 3008628 (1961-11-01), Gerteis et al.
patent: 3187996 (1965-06-01), Roelsgaard
patent: 5252038 (1993-10-01), Mangyo et al.
patent: 5538404 (1996-07-01), DiFlora et al.
patent: 5804775 (1998-09-01), Pinnington
patent: 6035963 (2000-03-01), Wollitz
Warren P. Mason, 1964, Academic Press, Physical Acoustics Principles and Methods, vol. 1—Part A, 1 page.
Belena John F
Samsung Gwangju Electronics Co. Ltd.
Westman Champlin & Kelly P.A.
LandOfFree
Hermetic 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 Hermetic compressor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hermetic compressor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2972810