Pumps – With muffler acting on pump fluid
Reexamination Certificate
1999-09-14
2001-03-27
Freay, Charles G. (Department: 3746)
Pumps
With muffler acting on pump fluid
C417S057000, C137S855000
Reexamination Certificate
active
06206655
ABSTRACT:
TECHNICAL FIELD
The present invention relates generally to a relatively compact compressor such as utilized in a refrigerator for home use or a freezer and, more particularly, to a valve mechanism or a suction system of such a compressor.
BACKGROUND ART
In recent years, valve mechanisms in compressors have been improved in numerous ways to increase the efficiency of the compressors. However, demands have also been made from the market not only to increase the efficiency of the compressor, but also to suppress noise emission from the compressor.
The prior art compressor valve mechanism is disclosed in, for example, the Japanese Laid-open Patent Publication (unexamined) No. 3-175174.
Hereinafter, with reference to
FIGS. 24
,
25
and
26
, the prior art compressor valve mechanism disclosed in the above mentioned Japanese Laid-open Patent Publication No. 3-175174 will be discussed.
FIG. 24
is a sectional view of the prior art valve mechanism in an assembled condition taken along the horizontal diction,
FIG. 25
is a longitudinal sectional view of
FIG. 24
, and
FIG. 26
is an exploded view of the prior art valve mechanism. In
FIGS. 24
to
26
, reference numeral
1
represents the valve mechanism, and reference numeral
4
represents a valve plate having two suction ports
2
and two discharge ports
3
both defined therein. A discharge reed valve
22
for selectively opening and closing the discharge ports
3
is retained within a recess
21
defined in the valve plate
4
. Reference numeral
23
represents a stopper rivetted at
24
to the valve plate for regulating the lift of the reed valve
22
. A suction reed valve
11
, a plate-like gasket
12
, the valve plate
4
, a head gasket
13
and a cylinder head
14
are all bolted to a cylinder
10
.
The cylinder
10
accommodates therein a piston drivingly coupled with an electric motor (not shown) for axial reciprocating movement within the cylinder
10
. The cylinder head
14
has a suction chamber
25
and a discharge chamber
26
defined therein in cooperation with the valve plate
4
.
The operation of the prior art compressor valve mechanism of the structure described above will now be described.
As a result of reciprocating movement of a piston
15
, a refrigerant gas within the suction chamber
25
is sucked into the cylinder
10
through the suction ports
2
in the valve plate
4
during opening of the suction reed valve
11
. The refrigerant gas is subsequently compressed within the cylinder
10
before it is discharged into the discharge chamber
26
in the cylinder head
14
through the discharge ports
3
during opening of the discharge reed valve
22
.
In the prior art valve mechanism discussed above, however, because the refrigerant gas is simultaneously discharged into the discharge chamber
26
through the two discharge ports
3
, refrigerant gas flows interfere with each other to hinder smooth streams of the refrigerant gas, thus lowering the discharge efficiency and the performance of the compressor. Furthermore, because simultaneous discharge of the refrigerant gas from the two discharge ports
3
into the discharge chamber
26
is intermittently performed, very large pressure pulsations and noises are undesirably generated.
Also, the discharge reed valve merely has only one resonant mode as streams of the refrigerant gas discharged respectively from the two discharge ports
3
push the discharge reed valve
22
simultaneously. Therefore, it has been difficult to make resonance of the reed valve
22
proper and also to optimize the discharge efficiency at about 3,000 revolutions per minute at 50 Hz and also at about 3,600 revolutions per minute at 60 Hz. Also, even in the case of a compressor such as an inverter in which the number of revolutions per minute is varied, there has been a problem in that changes in the number of revolutions per minute tend to be accompanied by considerable lowering of the efficiency.
In addition, since the discharge reed valve
22
merely has the single resonant mode, there has been another problem in that hissing sounds generated by the respective streams of the refrigerant gas discharged from the two discharge ports tend to be enhanced by interference to thereby result in considerable generation of noise.
Also, the discharge reed valve
22
is fixed in position within the recess
21
by the stopper
23
and the rivets
24
, requiring a complicated mounting and an inefficient assemblage.
Japanese Patent Publication (examined) No. 6-74786 discloses a suction system for an electrically-operated sealed compressor in which a muffler having a plurality of chambers partitioned from each other is employed for muffling. However, there has been a problem in that if the muffling feature is given priority, the suction efficiency tends to be lowered accompanied by reduction in performance.
Also, since a sucked gas represents an intermittent flow as a result of selective opening and closing of a reed valve, a flow inertia of a refrigerant gas cannot be sufficiently utilized and the charge on a cylinder tends to be lowered This tendency is enhanced when the muffling performance of the muffler is increased.
This sealed compressor requires the muffling performance of the muffler and the suction efficiency to be improved.
The present invention has been developed to overcome the above-described disadvantages.
It is accordingly an objective of the present invention to provide an improved electrically-operated sealed compressor which has a high discharge efficiency and in which sounds generated as a result of interference between discharged refrigerant gases are of a low level so as to accomplish noise suppression, and in which pulsation of the refrigerant gas is very small.
Another objective of the present invention is to provide an electrically-operated sealed compressor capable of accommodating changes in the number of revolutions.
A still further objective of the present invention is to provide an electrically-operated sealed compressor in which the discharge valve can easily be mounted to facilitate assemblage.
Another objective of the present invention is to provide an electrically-operated sealed compressor in which the stopper and the discharge valve can easily be fixed in position.
Still another objective of the present invention is to provide an electrically-operated sealed compressor capable of improving and maintaining the compressing performance of the compressor in a muffler without lowering the flow inertia of the refrigerant even if the charge on the cylinder is improved. and, Hence, the muffling performance is increased.
DISCLOSURE OF THE INVENTION
In accomplishing the above and other objectives, an electrically-operated sealed compressor according to the present invention comprises a cylinder, a cylinder head mounted on the cylinder and having a suction chamber defined therein and first and second discharge chambers defined therein, a piston accommodated in the cylinder, and a valve mechanism. The valve mechanism comprises a suction muffler and a valve plate having at least one suction port defined therein, first and second discharge ports defined therein, and first and second pass holes defined therein. The first discharge port and the first pass hole communicate with the first discharge chamber, while the second discharge port and the second pass hole communicate with the second discharge chamber. The valve mechanism also comprises first and second discharge valves mounted on the valve plate and accommodated in the first and second discharge chambers, respectively, a suction reed having a reed valve for selectively opening and closing the suction port, a discharge gasket for sealing the valve plate and the cylinder head, and a discharge muffler. The first and second discharge chambers are separated from each other by the discharge gasket to form respective independent spaces, while the first and second pass holes communicate with the discharge muffler.
This construction eliminates interference of refrigerant gas flows which has been hitherto caused by simultaneous introduc
Kita Ichiro
Tanaka Yasuhiko
Umeoka Ikutomo
Evora Robert Z.
Freay Charles G.
Matsushita Refrigeration Company
Wenderoth, Lind & Ponack L.L.P
LandOfFree
Electrically-operated sealed 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 Electrically-operated sealed compressor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electrically-operated sealed compressor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2478114