FIELD OF THE INVENTION
[0001] The invention in question relates to a hermetic compressor, and, more particularly,
a hermetic compressor provided with at least one fluid expansion chamber, that is,
a pulsation attenuating chamber that can be used in the discharge line (discharge
muffler) or in the suction line (suction muffler).
[0002] In accordance with the invention in question, the hermetic compressor disclosed herein
is distinguished in that it comprises an airtight housing and at least an additional
wall section, wherein the volume defined between the airtight housing and the additional
wall section ends up defining said fluid expansion chamber.
BACKGROUND OF THE INVENTION
[0003] As is well known to those skilled in the art, hermetic compressors, especially those
comprised of positive displacement compression mechanisms, include, among other components,
discharge expansion chambers (also referred to as "discharge mufflers") and suction
expansion chambers (also referred to as "suction muffler"). In general lines, the
fluid expansion chambers have the general function of attenuating the pulsations of
the useful fluid, being that the functional principles which governs the passive operation
of the fluid expansion chambers are widely known to professionals and theoreticians
in the area of acoustics, besides being particularly detailed in specialized technical
literature.
[0004] The current state of the art comprises an infinity of models and constructions of
fluid expansion chambers used in hermetic compressors.
[0005] There are, for example, constructions in which the volume of the discharge expansion
chamber is defined by a hollow modular body arranged, in a non-anchored manner, within
the airtight housing of the hermetic compressor. The fluid communication between the
compression mechanism head, the hollow modular body and the discharge duct is performed
by a rigid metal tubing.
[0006] There are, for example, constructions in which the volume of the discharge expansion
chamber is integrally or partially defined in the compressor block itself. The fluid
communication, between the compression mechanism head, the compressor block and the
discharge duct, is performed by a rigid metal tubing.
[0007] There are, for example, as described in the patent document
US 4,782,858, constructions in which the volume of the discharge expansion chamber is integrally
defined in the cap of the compression mechanism head. The fluid communication between
the compression mechanism head and the discharge duct is performed by a rigid metal
tubing.
[0008] There are, for example, as described in the patent document
US 2009/162215, constructions in which the volume of the discharge expansion chamber is segmented
in two, the first "sub volume" being defined integrally in the cap of the head and
the second "sub volume" being defined between the cap of the head and the outer face
of a segment of the compression cylinder block, the fluid communication between the
two "sub-volumes" being defined in the arrangement itself, without the overall structure
of the cylinder block being altered. The fluid communication between the compression
mechanism head and the discharge duct is performed by a rigid metal tubing.
[0009] It is noted, however, that regardless of the model or construction of the known expansion
chambers, they are always arranged within the airtight housing of the compressor,
that is, they are arranged in the internal environment whose useful volume is shared
with the compression mechanism, such as the electric motor, with the compressor block,
among other components and systems.
[0010] In a general manner, the fact that an expansion chamber is arranged within the airtight
housing generates at least three drawbacks, one from the thermal point of view, the
other from the dimensional point of view, and the third relating to aspects of reliability.
[0011] With regard to the thermal point of view, it is noted that the discharge expansion
chamber is arranged in an environment (within the airtight housing), whose temperature
is lower than the temperature of the discharge fluid, that is, the temperature outside
the discharge expansion chamber is less than its within temperature. Consequently,
the internal environment of the housing of the compressor (suction fluid) suffers
severe thermal exchange, after all, its temperature is pejoratively influenced by
the temperature of the circulating discharge fluid through the discharge expansion
chamber. As a consequence, there is an increase in the suction temperature of the
compressor and, in this way, reducing the volumetric efficiency and, hence, the energy
efficiency thereof.
[0012] As far as the dimensional point of view is concerned, it is noted that the discharge
expansion chamber occupies a useful volume which could otherwise be suppressed in
order to enable the miniaturization of the hermetic compressor housing, which currently
is unlikely. Another benefit of reducing internal compressor volume is related to
the application of high pressure useful refrigerants, such as CO
2, as well as flammable, wherein the compressors fall into the category of pressure
vessel safety, and the internal volume defines the criticality of the damage. Thus,
compressors with smaller internal volumes are advantageous for this type of application.
[0013] With regard to the reliability, it is noted that the reduction of the masses mounted
in the discharge tube, which has a relative movement between the housing and the internal
assembly of the compressor, especially the compressor block, when transporting the
compressor, and also in the moments of on and off of the compressor. The elimination
of these masses reduces the loads on the pipes, as well as avoids shocks of these
volumes with the internal components and the housing of the compressor.
[0014] It is, therefore, based on the above-described scenario that the invention in question
arises.
GOALS OF THE INVENTION
[0015] Thus, it is the primary goal of the invention in question to disclose a hermetic
compressor, provided with at least one fluid expansion chamber, whose useful volume
is narrowly defined between a section of one of the faces (inner or outer) of the
airtight housing of the compressor and at least one wall section adjacently attached
to one of the faces of the airtight housing of the compressor.
[0016] Accordingly, it is also a goal of the invention in question to provide a fluid expansion
chamber less susceptible to thermal exchanges and which occupies less or no useful
space within the airtight housing of the hermetic compressor.
[0017] It is also a goal of the invention in question that the fluid expansion chamber of
the hermetic compressor now treated be less susceptible to problems and failures of
transport and application of the compressor at the times of turning the compressor
on and off.
[0018] Thus, it is one of the goals of the invention in question that the general concept
of a fluid expansion chamber, whose useful volume is narrowly defined between a section
of one of the faces (inner or outer) of the airtight housing of the compressor and
at least a wall section adjacently attached to one of the faces of the airtight housing
of the compressor can be used both as a discharge muffler and a suction muffler.
BRIEF DESCRIPTION OF THE INVENTION
[0019] The goals summarized above are fully achieved by the hermetic compressor disclosed
herein, which comprises an airtight housing, at least one reciprocating compression
mechanism arranged within the airtight housing and at least one fluid expansion chamber.
Said fluid expansion chamber is formed between one of the faces of the airtight housing
and the inner face of a first modular body, hermetically attached to one of the faces
of the airtight housing and comprises at least one inlet path and at least one outlet
path.
[0020] In accordance with the invention in question, the fluid expansion chamber may comprise
a discharge fluid expansion chamber (discharge muffler) or a suction fluid expansion
chamber (suction muffler).
[0021] Also in accordance with the invention in question, the fluid expansion chamber may
be external (formed between the outer face of the airtight housing and the inner face
of a first modular body hermetically attached to the outer face of the airtight housing)
and/ or internal (formed between the inner face of the airtight housing and the inner
face of a first modular body hermetically attached to the inner face of the airtight
housing).
[0022] Further, still in accordance with the invention in question, the inlet path and the
outlet path of the fluid expansion chamber can be fluidly aligned or misaligned.
[0023] Optionally, the hermetic compressor disclosed herein further comprises at least one
second fluid expansion chamber fluidly connected, in series, to the "main" fluid expansion
chamber.
[0024] In one of the possible embodiments of such optional embodiment, the second fluid
expansion chamber is internal, being arranged within the airtight housing and may
be formed, at least partially, between the inner face of the airtight housing and
the inner face of a second modular body or be formed, at least partially, between
the outer face of the first modular body and the inner face of a second modular body.
[0025] In another of the possible embodiments of such optional embodiment, the second fluid
expansion chamber is external, being arranged on the exterior of the airtight housing
and may be formed, at least partially, between the outer face of the airtight housing
and the inner face of a second modular body or be formed, at least partially, between
the outer face of the first modular body and the inner face of a second modular body.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The invention in question will be particularly detailed on the basis of the illustrative
Figures listed below, which:
Figures 1A and 1B illustrate, in a schematic form, the most basic and simplified embodiments
of the invention in question;
Figures 2A, 2B, 2C and 2D illustrate, in a schematic form, possible embodiments of
the optional embodiment of the invention in question; and
Figure 3 illustrates, in a schematic form, another possible embodiment of the optional
embodiment of the invention in question.
DETAILED DESCRIPTION OF THE INVENTION
[0027] In accordance with the central goals of the invention in question, it is desired
to "shift" the volume of a traditional fluid expansion chamber (discharge or suction),
normally displaced within the airtight housing of a hermetic compressor, to the vicinity
of said airtight housing, so that such volume becomes an integral part of the housing
of the compressor.
[0028] Of course, such invention has the potential to optimize the internal volume of the
compressor, in addition to reducing the emission of heat within the housing, promoting
greater energy efficiency. In addition, such invention simplifies the overall manufacturing
process of the compressor, after all, traditional brazing processes are replaced by
faster and less expensive welding processes.
[0029] In a general manner, the hermetic compressor treated herein is a traditional hermetic
compressor, and, of course, certain details not relevant for the understanding of
the invention in question have been omitted and/ or deleted. It is again emphasized
that omission or deletion of these details (components that integrate the compression
or the damping mechanisms, for example) does not prejudice the full understanding
of the invention in question.
[0030] The invention in question, in its inventive core, is illustrated in Figures 1A and
1B.
[0031] As illustrated in these Figures, the hermetic compressor disclosed herein comprises
an airtight housing and a fluid expansion chamber, being that the great inventive
merit of the invention in question consists in the fact that said fluid expansion
chamber - rather than being detached and conformed in itself, as it happens in the
current state of the art - is formed between one of the faces of the airtight housing
and the inner face of a first modular body hermetically attached to one of the faces
of the airtight housing.
[0032] Specifically, as illustrated in Figure 1A, said fluid expansion chamber (2) is external
to the airtight housing (1), being formed between the outer face (12) of the airtight
housing (1) and the inner face (31) of the first modular body (3), which is, in turn,
hermetically attached to the same outer face (12) of the airtight housing (1). It
is further noted that, such as illustrated, said fluid expansion chamber (2) is a
discharge fluid expansion chamber.
[0033] Specifically, as illustrated in Figure 1B, said fluid expansion chamber (2) is internal
to the airtight housing (1), being formed between the inner face (11) of the airtight
housing (1) and the inner face (31) of the first modular body (3), which is, in turn,
hermetically attached to the same inner face (11) of the airtight housing (1). It
is further noted that, such as illustrated, said fluid expansion chamber (2) is a
suction fluid expansion chamber.
[0034] In both embodiments illustrated in Figures 1A and 1B, it is noted that the fluid
expansion chamber (2) comprises at least one inlet path (21) and at least one outlet
path (22).
[0035] In the embodiment illustrated in Figure 1A, the inlet path (21) is related to a fluidic
communication means (tube or mere through-hole, to give only two examples) which,
bypassing the airtight housing (1), connects its internal environment to the volume
of the fluid expansion chamber (2). The outlet path (22) is related to a fluid communication
means (discharge duct tube, to give only one example) able to allow the connection
between the hermetic compressor and the discharge line of an external system (not
illustrated), such as, for example, a cooling system.
[0036] In the embodiment illustrated in Figure 1B, the inlet path (21) is related to a fluidic
communication means (suction duct tube, to give only one example) which, bypassing
the airtight housing (1), is able to allow the connection between the suction line
of an external system (not illustrated), such as, for example, a cooling system and
the hermetic compressor. The outlet path (22) is related to a fluidic communication
means (tube or mere through-hole, to give only two examples) capable of connecting
the volume of the fluid expansion chamber (2) to the internal environment of the compressor
or to the cylinder of the compression mechanism (not illustrated).
[0037] In both embodiments illustrated in Figures 1A and 1B, in addition to the remaining
embodiments described in the invention in question, the first modular body (3) is
preferably made of metal alloy and attached to one of the faces (11 and 12) of the
airtight housing (1), preferably by means of welding. Nothing prevents the modular
body from being manufactured with other types of materials, such as polymeric, that
the fixing is of alternative forms, such as, for example, glue.
[0038] Although the invention in question does not intentionally address thermal and acoustic
issues, it is worth emphasizing that the general, dimensional and structural format
of the first modular body (3), as well as the general features of the fastening medium,
must respect the features of acoustics of each project. In this regard, it is most
important to note that in any of the embodiments illustrated in Figures 1A and 1B,
the inlet path (21) and the outlet path (22) of the fluid expansion chamber (2) can
be arranged in a fluidly aligned manner or in a fluidly misaligned manner.
[0039] Optional embodiments of the invention in question, in accordance with the inventive
core described above, are illustrated in Figures 2A, 2B, 2C and 2D.
[0040] In all these optional embodiments it is noted the existence of said fluid expansion
chamber (2) (internal or external to the airtight housing (1), formed between one
of the faces (11 and 12) of the airtight housing (1) and the inner face (31) of a
first modular body (3) hermetically attached to one of the faces (11 and 12) of the
airtight housing (1)) and the existence of at least one second fluid expansion chamber
(4) fluidly connected, in series, to the fluid expansion chamber (2). The fluid expansion
chambers (2 and 4) can conform a volume-in-series for discharge fluid or a volume-in-series
for suction fluid.
[0041] In general lines, the formation of the second fluid expansion chamber (4) always
has a second modular body (5), which, also in general lines, is substantially analogous
to the first modular body (3).
[0042] The formatting of the second fluid expansion chamber (4), always employing the second
modular body (5), can be varied, some examples being illustrated in cited Figures
2A, 2B, 2C and 2D.
[0043] As illustrated in Figure 2A, the fluid expansion chamber (2) and the second fluid
expansion chamber (4) are both external and, preferably, dedicated to the discharge
fluid. In this embodiment, the second fluid expansion chamber (4) is formed only between
the outer face (32) of the first modular body (3) and the inner face (51) of a second
modular body (5).
[0044] As illustrated in Figure 2B, the fluid expansion chamber (2) and the second fluid
expansion chamber (4) are both internal and, preferably, dedicated to the suction
fluid. In this embodiment, the second fluid expansion chamber (4) is formed between
the outer face (32) of the first modular body (3), the inner face (11) of the airtight
housing (1) and the inner face (51) of a second modular body (5).
[0045] As illustrated in Figure 2C, the fluid expansion chamber (2) and the second fluid
expansion chamber (4) are both external and, preferably, dedicated to the discharge
fluid. In this embodiment, the second fluid expansion chamber (4) is formed between
the outer face (32) of the first modular body (3), the outer face (12) of the airtight
housing (1) and the inner face (51) of a second modular body (5).
[0046] As illustrated in Figure 2D, the fluid expansion chamber (2) and the second fluid
expansion chamber (4) are both internal and, preferably, dedicated to the suction
fluid. In this embodiment, the second fluid expansion chamber (4) is formed only between
the inner face (11) of the airtight housing (1) and the inner face (51) of a second
modular body (5).
[0047] In these four embodiments, it is further noted that the fluid expansion chamber (4)
comprises an outlet path (6), which is directed to a fluidic communication means (traditional
tube, mere through-hole or through-tube, to give only three examples). In this sense,
it is noted that the "inlet path" of said fluid expansion chamber (4) always ends
up being defined by the outlet path (22) of the fluid expansion chamber (2).
[0048] The constructive details described (and omitted) with respect to the fluid expansion
chamber (2) (possibility of structural and dimensional variation, and preferred form
of fixation by welding, for example) are similarly observed in the fluid expansion
chamber (4).
[0049] In contrast to the optional embodiments illustrated in Figures 2A, 2B, 2C and 2D,
the optional embodiment illustrated in Figure 3 provides for the use of two fluid
expansion chambers, fluidly connected, in series, one of these chambers being internally
arranged (in relation to the housing of the compressor) and the other of these chambers
externally arranged (in relation to the housing of the compressor).
[0050] Thus, as arbitrarily defined in Figure 3, there is provided a hermetic compressor
comprising an airtight housing (1), a first fluid expansion chamber (2) and a second
fluid expansion chamber (4), such chambers being fluidly connected, in series, defining
a volume-in-series for discharge fluid (it may of course also define a volume-in-series
for suction fluid).
[0051] In particular, the first fluid expansion chamber (2) is specially formed only between
the inner face (11) of the airtight housing (1) and the inner face (31) of a first
modular body (3) hermetically attached to the inner face (11) of the airtight housing
(1), while the second fluid expansion chamber (4) is specially formed only between
the outer face (12) of the airtight housing (1) and the inner face (31) of a first
modular body (3) hermetically attached to the outer face (12) of the airtight housing
(1). The fluid connection between the volumes occurs in an analogous manner to the
constructions and options illustrated in Figures 2A, 2B, 2C and 2D.
[0052] It is important to emphasize that the above description has the sole purpose of describing
by way of example the particular embodiment of the utility model in question. Therefore,
it is clear that modifications, variations and constructive combinations of the elements
performing the same function, in substantially the same manner, to achieve the same
results, remaining within the scope of protection delimited by the appended claims.
1. Hermetic compressor, comprising:
- an airtight housing (1);
- at least one reciprocating compression mechanism (not illustrated) arranged within
the airtight housing (1); and
- at least one fluid expansion chamber (2);
said hermetic compressor being especially characterized in that said fluid expansion chamber (2) is formed between one of the faces (11, 12) of the
airtight housing (1) and the inner face (31) of a first modular body (3) is hermetically
attached to one of the faces (11, 12) of the airtight housing (1); and
said fluid expansion chamber (2) comprises at least one inlet path (21) and at least
one outlet path (22).
2. Hermetic compressor, according to claim 1, characterized in that the fluid expansion chamber (2) comprises a discharge fluid expansion chamber.
3. Hermetic compressor, according to claim 1, characterized in that the fluid expansion chamber (2) comprises a suction fluid expansion chamber.
4. Hermetic compressor, according to claim 1, characterized in that the fluid expansion chamber (2) is external, being formed between the outer face
(12) of the airtight housing (1) and the inner face (31) of a first modular body (3)
hermetically attached to the outer face (12) of the airtight housing (1).
5. Hermetic compressor, according to claim 1, characterized in that the fluid expansion chamber (2) is internal, being formed between the inner face
(11) of the airtight housing (1) and the inner face (31) of a first modular body (3)
hermetically attached to the inner face (11) of the airtight housing (1).
6. Hermetic compressor, according to claim 1, characterized in that the inlet path (21) and the outlet path (22) of the fluid expansion chamber (2) are
fluidly aligned.
7. Hermetic compressor, according to claim 1, characterized in that the inlet path (21) and the outlet path (22) of the fluid expansion chamber (2) are
fluidly misaligned.
8. Hermetic compressor, according to claim 1, characterized in that it further comprises at least one second fluid expansion chamber (4) fluidly connected,
in series, to the fluid expansion chamber (2).
9. Hermetic compressor, according to claim 8, characterized in that said second fluid expansion chamber (4) is internal, being arranged within the airtight
housing (1).
10. Hermetic compressor, according to claim 9, characterized in that said second fluid expansion chamber (4) is formed, at least partially, between the
inner face (11) of the airtight housing (1) and the inner face (51) of a second modular
body (5).
11. Hermetic compressor, according to claim 9, characterized in that said second fluid expansion chamber (4) is formed, at least partially, between the
outer face (32) of the first modular body (3) and the inner face (51) of a second
modular body (5).
12. Hermetic compressor, according to claim 8, characterized in that said second fluid expansion chamber (4) is external, being arranged on the outside
of the airtight housing (1).
13. Hermetic compressor, according to claim 12, characterized in that said second fluid expansion chamber (4) is formed, at least partially, between the
outer face (12) of the airtight housing (1) and the inner face (51) of a second modular
body (5).
14. Hermetic compressor, according to claim 12, characterized in that said second fluid expansion chamber (4) is formed, at least partially, between the
outer face (32) of the first modular body (3) and the inner face (51) of a second
modular body (5).