Technical Field
[0001] The present invention relates to a hermetic two-stage compressor.
Background Art
[0003] In the related art, for example, a hermetic two-stage compressor is known, which
is used for refrigeration air conditioning and includes a low stage-side compression
section and a high stage-side compression section which are sealed in a housing. In
addition, an example of the hermetic two-stage compressor is disclosed in PTL 1.
[0004] In the hermetic two-stage compressor of PTL 1, a rotary compressor is disposed as
a low stage-side compression section, a scroll compressor is disposed as a high stage-side
compression section, a gas supplied into a housing is compressed by the rotary compressor,
and thereafter, the gas is further compressed by the scroll compressor to be discharged
from the housing. The hermetic two-stage compressor is operated in a state where a
lubricating oil of the low stage-side compression section and the high stage-side
compression section is held in the housing.
[0005] Here, in the hermetic two-stage compressor disclosed in PTL 1, a bearing bracket
is provided in a divided portion of an upper and lower split type housing, and an
oil circulation amount (OC%) in a refrigerating cycle is reduced by allowing the gas
in a central region where an oil content is small to flow into the scroll compressor
while preventing the gas in an outer peripheral region inside the housing containing
a lot of oil from flowing into the scroll compressor.
Citation List
Patent Literature
[0006]
[PTL 1] Japanese Unexamined Patent Application Publication No. 2009-180107
[PTL 2] EP 2177768 discloses a multi-stage compressor.
[PTL 3] EP 1371852 discloses a hermetic compressor lubrication system.
[PTL 4] EP 2735742 discloses a fluid machine.
Summary of Invention
Technical Problem
[0007] However, in the bearing bracket of PTL 1, in a case where a member for decreasing
the oil circulation amount (OC%) in the refrigerating cycle is provided in the housing
by welding, there is a possibility that strain occurs in the housing. Accordingly,
it is difficult to accurately manufacture the hermetic two-stage compressor, and it
takes time and labor to manufacture. In addition, the bearing bracket of the hermetic
two-stage compressor of PTL 1 receives a load from a bearing case, and thus, it is
necessary to increase a thickness so as to secure strength. As a result, an internal
volume of the housing decreases, which is disadvantageous when oil is separated from
the gas.
[0008] Accordingly, the present invention is to provide a hermetic two-stage compressor
capable of being easily manufactured and effectively separating oil from a gas.
Solution to Problem
[0009] A first embodiment and a second embodiment of the present invention are defined in
appended claims 1 and 6 respectively.
[0010] In the hermetic two-stage compressor, the oil of the oil storage and the gas are
compressed in the low stage-side compression section. Accordingly, the oil is contained
in the gas which is discharged from the low stage-side compression section. A portion
of the gas containing the oil flows out toward the motor, and thereafter, flows to
the high stage-side compression section through the gap between the stator and the
rotor or a through-hole provided in the rotor. In addition, when the gas passes through
the motor, the oil in the gas comes into contact with the rotor or an oil separation
plate provided above the rotor, and thus, a content of the oil in the gas decreases.
Meanwhile, the gas which has passed through a portion between the stator and the housing
does not come into contact with the rotor and flows toward the high stage-side compression
section as it is. Accordingly, the gas flows toward the high stage-side compression
section in a state where the content of the oil in the gas is high. That is, the amount
of the oil in the gas discharged from the low stage-side compression section decreases
on the radially inner side of the housing and increases on the radially outer side
thereof.
[0011] Here, according to a simple method in which the restricting surface is provided in
the bearing casing, the flow of the gas to the suction opening on the radially outer
side can be restricted. Therefore, it is possible to prevent the gas having a high
content of oil on the radially outer side flows into the suction channel through suction
opening as it is, and the gas on the radially inner side having a low content of oil
can flow into the suction channel through the suction opening. As a result, it is
possible to supply the gas having a low content of oil to the high stage-side compression
section, and it is possible to decrease the amount of the oil in the gas which is
compressed by the high stage-side compression section and is discharged therefrom.
Therefore, it is possible to decrease an oil circulation amount (OC%) in a system
including the hermetic two-stage compressor.
[0012] In addition, if the gas on the radially outer side comes into contact with the restricting
surface, the oil in the gas is attached to the restricting surface, and the gas in
which the content of the oil has decreased is guided to the radially inner side by
the restricting surface and flows from the suction opening into the suction channel.
Accordingly, in a state where the amount of the oil in the gas is decreased by the
restricting surface, the gas is supplied from the suction channel to the high stage-side
compression section, and thus, it is possible to decrease the amount of the oil in
the gas which is compressed by the high stage-side compression section and is discharged
therefrom, and it is possible to decrease the oil circulation amount (OC%) in the
system.
[0013] Moreover, the hermetic two-stage compressor may further include an inflow restricting
plate which is fixed to the bearing casing, is formed in a plate shape, and includes
the restricting surface on the one side (first end side) of the axial direction.
[0014] In this way, the inflow restricting plate is provided in the bearing casing, and
thus, it is possible to provide the restricting surface in the bearing casing. Therefore,
compared to a case where a member corresponding to the inflow restricting plate is
attached to the housing so as to provide the restricting surface, it is possible to
very easily provide the restricting surface in the bearing casing. In addition, it
is possible to easily provide the restricting surface in the existing bearing casing.
[0015] Moreover, in the hermetic two-stage compressor according to the second embodiment
of the invention the restricting surface includes a flat surface which is provided
on an end portion on the radially outer side which is an inner surface side of the
housing and is perpendicular to the axis to be formed in an annular shape about the
axis and an inclined surface which is inclined toward the one side (first end side)
in the axial direction from the flat surface toward the radially inner side so as
to be formed in a truncated conical shape about the axis.
[0016] In this way, the inclined surface which is formed in a truncated conical shape is
provided as the restricting surface, and thus, it is possible to form the opening
portion which is formed in an annular shape about the axis so as to extend from the
suction opening to the one side (first end side) in the axial direction. Accordingly,
the opening portion extending from the suction opening can be formed in an annular
shape, and thus, an opening area can be secured, and it is possible to secure a flow
rate of the gas flowing from the inside of the housing into the suction channel. In
addition, the gas having a high content of oil in the radially outer side region flows
to the radially inner side along the flat surface of the restricting surface, and
thereafter, collides with the inclined surface, and thus, the oil can be attached
to the inclined surface. Accordingly, the gas flows into the suction channel in a
state where the content of the oil in the gas further decreases, and thus, it is possible
to decrease the amount of the oil in the gas supplied to the high stage-side compression
section, and it is possible to decrease the amount of the oil in the gas which is
compressed by the high stage-side compression section and is discharged therefrom.
Accordingly, it is possible to further decrease the oil circulation amount (OC%) in
the system.
[0017] Moreover, in the hermetic two-stage compressor an inner edge portion on the radially
inner side of the restricting surface may be disposed at a position on the radially
inner side of the stator, and the restricting surface may close a portion of the suction
opening so as to secure an intake amount of the gas required in the high stage-side
compression section.
[0018] In this way, the inner edge portion of the restricting surface is positioned on the
radially inner side from the stator, and thus, the restricting surface extends to
the position of the rotor. Accordingly, the gas which comes into contact with the
rotor so as to sufficiently decrease the amount of the oil can flow from the suction
opening into the suction channel. Therefore, it is possible to further decrease the
amount of the oil in the gas which is compressed by the high stage-side compression
section and is discharged therefrom, and it is possible to further decrease the oil
circulation amount (OC%) in the system. Moreover, at this case, it is possible to
secure an intake amount of the gas required in the high stage-side compression section,
and it is possible to prevent compression efficiency in the high stage-side compression
section from decreasing.
[0019] In addition, the hermetic two-stage compressor may further include a seal member
which is provided in a gap between an outer edge portion on the radially outer side
of the restricting surface and the inner surface of the housing.
[0020] The gas having a high content of oil which has passed through a portion between the
housing and the stator in the radially outer side region in the housing can be prevented
from flowing from the portion between the restricting surface and the housing into
the high stage-side compression section as it is, by the seal member. Accordingly,
it is possible to further decrease the amount of the oil in the gas which is compressed
by the high stage-side compression section and is discharged therefrom, and it is
possible to further decrease the oil circulation amount (OC%) in the system.
[0021] In addition, the hermetic two-stage compressor may further include an oil return
section which is provided at a position of an end portion on the radially outer side
in the bearing casing and causes the high stage-side compression section and the one
side (first end side) in the axial direction from the bearing casing in the housing
to communicate with each other such that oil from the high stage-side compression
section can flow through the oil return section.
[0022] The oil return section is provided, and thus, the oil used for lubricating in the
high stage-side compression section is returned into the housing through the oil return
section. Accordingly, it is possible to further decrease the amount of the oil in
the gas which is compressed by the high stage-side compression section and is discharged
therefrom, and it is possible to further decrease the oil circulation amount (OC%)
in the system.
[0023] In addition, the oil return section is provided on the end portion on the radially
outer side of the bearing casing, and thus, the oil return section is provided at
a position separated from the suction opening which is open to the radially inner
side. Therefore, the oil which is returned from the oil return section to the housing
can be prevented from flowing from the suction opening into the suction channel as
it is. Accordingly, it is possible to further decrease the amount of the oil in the
gas which is compressed by the high stage-side compression section and is discharged
therefrom, and it is possible to further decrease the oil circulation amount (OC%)
in the system.
[0024] Moreover, in the hermetic two-stage compressor an accommodation portion which extends
in the axial direction and through which a wire of the motor can be inserted may be
provided in the bearing casing, and the hermetic two-stage compressor may further
include a seal member which is provided in a gap between the restricting surface and
the wire of the motor.
[0025] Even when the accommodation portion into which the wire of the motor is inserted
is formed in the bearing casing, the gap between the restricting surface and the wire
of the motor can be sealed by the seal member. Accordingly, it is possible to prevent
the gas containing the oil from being supplied to the high stage-side compression
section through the gap as it is.
Advantageous Effects of Invention
[0026] According to the hermetic two-stage compressor, the method of providing the restricting
surface in the bearing casing is used, and thus, it is possible to easily manufacture
the hermetic two-stage compressor, and it is possible to effectively separate the
oil in the gas by the restricting surface.
Brief Description of Drawings
[0027]
Fig. 1 is a longitudinal sectional view showing a hermetic two-stage compressor according
to a first embodiment of the present invention.
Fig. 2 shows the hermetic two-stage compressor according to the first embodiment of
the present invention and is a longitudinal sectional view at a sectional position
from the sectional position of Fig. 1 in a circumferential direction.
Fig. 3 is a view showing a bearing casing and an inflow restricting plate of the hermetic
two-stage compressor according to the first embodiment of the present invention and
shows a cross section taken along line I-I of Fig. 1.
Fig. 4 is a longitudinal sectional view showing a hermetic two-stage compressor according
to a second embodiment of the present invention.
Fig. 5 is a view showing a bearing casing and an inflow restricting plate of the hermetic
two-stage compressor according to the second embodiment of the present invention and
shows a cross section taken along line IV-IV of Fig. 4.
Fig. 6 is a view showing a bearing casing and an inflow restricting plate of a hermetic
two-stage compressor according to a modification example of the embodiment of the
present invention.
Description of Embodiments
[First Embodiment]
[0028] Hereinafter, a hermetic two-stage compressor 1 (hereinafter, referred to as a two-stage
compressor 1) according to a first embodiment of the present invention will be described.
[0029] As shown in Figs. 1 and 2, for example, the two-stage compressor 1 compresses a refrigerant
R which is a gas such as carbon dioxide. The two-stage compressor 1 includes a housing
11, a rotary compressor (low stage-side compression section) 12, a scroll compressor
(high stage-side compression section) 13, an electric motor 14, a rotary shaft 15,
and a bearing device 30 which are provided inside the housing 11, and an inflow restricting
plate 61 which is fixed to the bearing device 30.
[0030] The housing 11 includes a main body portion 21 which is formed in a cylindrical shape,
and an upper cover portion 22 and a lower cover portion 23 which close an upper opening
and a lower opening of the main body portion 21. In addition, a space inside the housing
11 is sealed.
[0031] The rotary shaft 15 is disposed to extend vertically inside the housing 11.
[0032] The electric motor 14 is disposed on an outer peripheral side of the rotary shaft
15 and rotates the rotary shaft 15 around an axis X. That is, the electric motor 14
includes a rotor 38 which is fixed to an outer peripheral surface of the rotary shaft
15, and a stator 39 which radially faces the rotor 38 with a gap between the stator
39 and the outer peripheral surface of the rotor 38 and is fixed to an inner surface
of the main body portion 21 of the housing 11.
[0033] The electric motor 14 is connected to a power source (not shown) via a wire 14a and
rotates the rotary shaft 15 by power from the power source. A portion of the stator
39 in a circumferential direction is fixed to the inner surface of the housing 11,
and in portions other than the portion fixed to the inner surface of the housing 11,
the inner surface of the housing 11 and the stator 39 are disposed with a gap S in
a radial direction.
[0034] The rotary compressor 12 is disposed at a position adjacent to the lower cover portion
23 at a lower portion which is one in a direction of the axis X of the electric motor
14 inside the housing 11. The rotary compressor 12 includes an eccentric shaft portion
41 which is provided on the rotary shaft 15, a piston rotor 42 which is fixed to the
eccentric shaft portion 41 and is eccentrically rotated about the axis X according
to a rotation of the rotary shaft 15, and a cylinder 44 which includes a compression
chamber C1 accommodating the piston rotor 42 is formed inside the cylinder 44.
[0035] A suction hole 44a through which the refrigerant R can flow into the cylinder 44
is formed in the cylinder 44. A suction pipe 33 which is provided to penetrate the
main body portion 21 of the housing 11 is connected to the suction hole 44a and the
refrigerant R is supplied through the suction pipe 33 from the outside of the housing
11. In addition, a discharge hole (not shown) is formed in the cylinder 44, and the
refrigerant R compressed by the rotary compressor 12 is discharged from the discharge
hole to a region in the housing 11 in which the electric motor 14 is provided.
[0036] In addition, oil A is stored in the bottom portion of the housing 11 and an oil storage
O1 is provided in the bottom portion. When the oil A is initially sealed, a liquid
surface of the oil storage O1 is positioned above the rotary compressor 12. Accordingly,
the rotary compressor 12 is driven in the oil storage O1.
[0037] The scroll compressor 13 is disposed above the electric motor 14 inside the housing
11. The scroll compressor 13 includes a fixed scroll 51 which is fixed to an upper
bearing 31 and an orbiting scroll 57 which is disposed to face the fixed scroll 51
below the fixed scroll 51.
[0038] The fixed scroll 51 includes an end plate 52 which is fixed to an upper surface
of the upper bearing 31 and a fixed lap 53 which protrudes downward from the end plate
52. A discharge hole 52a which vertically penetrates the end plate 52 is formed at
a center portion (in the vicinity of the axis X) of the end plate 52.
[0039] The orbiting scroll 57 includes an end plate 58 which is disposed to be interposed
between the bearing device 30 (upper bearing 31 described below) and the end plate
52 of the fixed scroll 51 in the direction of the axis X and is fixed to the rotary
shaft 15, and an orbiting lap 59 which protrudes upward from the end plate 58.
[0040] The end plate 58 is fixed to an eccentric shaft portion 56 provided on an upper end
of the rotary shaft 15 and is eccentrically rotated about the axis X according to
the rotation of the rotary shaft 15.
[0041] The orbiting lap 59 meshes with the fixed lap 53, and thus, a compression chamber
C2 in which the refrigerant R is compressed is formed between the orbiting lap 59
and the fixed lap 53.
[0042] Here, a suction hole (not shown) is formed in the fixed scroll 51, and the refrigerant
R which is compressed by the rotary compressor 12 and is discharged into the housing
11 can be sucked into the compression chamber C2 via the bearing device 30 through
the suction hole. The refrigerant R compressed in the compression chamber C2 is discharged
to the outside of the housing 11 from a discharge pipe 34 through the discharge hole
52a of the fixed scroll 51, and the discharge pipe 34 is open to a space surrounded
by the fixed scroll 51 fixed to the upper portion of the fixed scroll 51 in the housing
11 and the discharge cover 50 and is provided to penetrate the housing 11 so as to
extend the outside of the housing 11.
[0043] The bearing device 30 includes the upper bearing 31 which is provided on the upper
portion of the housing 11 inside the housing 11, and lower bearings 32A and 32B which
are provided on the lower portion of the housing 11 inside the housing 11.
[0044] The lower bearings 32A and 32B rotatably support the rotary shaft 15 with respect
to the housing 11 at the lower portion of the housing 11. Specifically, the rotary
compressor 12 is vertically disposed in the direction of the axis X between the lower
bearings 32A and 32B, and the lower bearings 32A and 32B are fixed to the cylinder
44 by a bolt 48.
[0045] The upper bearing 31 includes a bearing 31a which rotatably supports the rotary shaft
15 around the axis X of the rotary shaft 15 with respect to the housing 11 and a bearing
casing 31b which supports the bearing 31a on the housing 11 integrally with the bearing
31a.
[0046] As shown in Figs. 1 to 3, a plurality of suction channels FC are provided in the
bearing casing 31b, and the suction channels FC extend to be parallel to the axis
X over the entire region of the bearing casing 31b in the direction of the axis X
with intervals to each other in the circumferential direction. In the present embodiment,
each of the suction channels FC is a recessed groove having a rectangular cross section
which is recessed from the outer peripheral surface of the bearing casing 31b toward
the radially inner side.
[0047] In addition, a suction opening FCa is provided in the bearing casing 31b, and the
suction opening FCa extends from a lower end of the suction channel FC toward the
radially inner side so as to be continued to the lower side which is one side (first
end side) of the axis X and is open in a fan shape downward when the bearing casing
31b is viewed.
[0048] In addition, a recessed portion (accommodation portion) 31c is provided in the bearing
casing 31b, and the recessed portion 31c is recessed over the entire region in the
direction of the axis X from the outer peripheral surface toward the radially inner
side at a position at which the recessed portion does not interfere with the suction
opening FCa. The wire 14a of the electric motor 14 is disposed inside the recessed
portion. A seal member 65 is provided in a gap among the recessed portion 31c, the
wire 14a, and the inner surface of the housing 11. For example, as the seal member
65, a seal material such as a resin can be used.
[0049] In addition, a bearing channel 31d (refer to Fig. 2) is formed in the bearing casing
31b, and the bearing channel 31d radially penetrates the bearing casing 31b and is
open to the inside of the housing 11 at a position in the direction of the axis X
at which the orbiting scroll 57 is fixed to the eccentric shaft portion 56.
[0050] In addition, an oil return pipe (oil return section) 72 is provided in the bearing
casing 31b, and, at a position at which the oil return pipe 72 does not interfere
with the suction opening FCa and the recessed portion 31c and a position of an end
portion on the radially outer side, the oil return pipe 72 communicates with the bearing
channel 31d, penetrates the bearing casing 31b toward the electric motor 14 to extend
along the inner surface of the housing 11, and protrudes downward from the bearing
casing 31b.
[0051] As shown in Fig. 3, the inflow restricting plate 61 is fixed to the bearing casing
31b by bolts 60 from below. The inflow restricting plate 61 is formed in an annular
shape about the axis X. The inflow restricting plate 61 includes a plurality of notches
63, which are cut out from the end portion on the radially inner side toward the radially
inner side, at positions corresponding to the suction openings FCa. A lower surface
of the inflow restricting plate 61 becomes a restricting surface 62, and a bottom
portion of each notch 63 forms an inner edge portion 62a of the restricting surface
62. The inner edge portion 62a has a curved shape formed along the circumferential
direction. The inner edge portion 62a is positioned at a radially intermediate position
of the suction opening FCa, and as a result, only the radially inner position of the
suction opening FCa is open toward the electric motor 14 by the inflow restricting
plate 61. Accordingly, a flow of the refrigerant R to the suction opening FCa on the
radially outer side is restricted by the restricting surface 62.
[0052] In addition, a notch 61a is provided in the inflow restricting plate 61, and the
notch 61a is recessed from the outer edge portion 62b toward the radially inner side
at a position corresponding to the position of the wire 14a so as not to interfere
with the wire 14a.
[0053] As shown in Fig. 1, when viewed from a cross section including the axis X, the restricting
surface 62 is provided to protrude from the inner surface of the housing 11 toward
the radially inner side.
[0054] In addition, in the present embodiment, a seal member 66 is provided in a gap between
the inner surface of the housing 11 and an outer edge portion 62b (an end edge on
the radially outer side along the inner surface of the housing 11) of the restricting
surface 62. As the seal member 66, a seal member formed of a resin, an O ring, or
the like can be used.
[0055] In the two-stage compressor 1 of the above-described present embodiment, the oil
A of the oil storage O1 and the refrigerant R are compressed by the rotary compressor
12. Accordingly, the oil A is included in the refrigerant R discharged from the rotary
compressor 12. A portion of the refrigerant R including the oil A flows out toward
the electric motor 14, and thereafter, flows toward the scroll compressor 13 through
the gap between the stator 39 and the rotor 38 or the through-hole 37 provided in
the rotor 38. In addition, when the refrigerant R passes through the electric motor
14, the oil A in the refrigerant R comes into contact with the rotor 38 or an oil
separation plate 38a which is provided on the rotor 38 and extends in the radial direction,
and thus, a content of the oil A in the refrigerant R decreases.
[0056] Meanwhile, the refrigerant R which has passed through the gap S between the stator
39 and the housing 11 does not come into contact with the rotor 38 and flows toward
the scroll compressor 13 as it is. Accordingly, the refrigerant R flows toward the
scroll compressor 13 in a state where the content of the oil A in the refrigerant
R is high. That is, the amount of the oil A in the refrigerant R discharged from the
rotary compressor 12 decreases on the radially inner side of the housing 11 and increases
on the radially outer side thereof.
[0057] Here, in the present embodiment, the inflow restricting plate 61 having the restricting
surface 62 is provided in the bearing casing 31b, and thus, the flow of the refrigerant
R to the suction opening FCa on the radially outer side can be restricted. Accordingly,
it is possible to prevent the refrigerant R having a high content of oil A on the
radially outer side flows into the suction channel FC through the suction opening
FCa as it is. In addition, the refrigerant R on the radially inner side having a low
content of oil A can flow into the suction channel FC through the suction opening
FCa.
[0058] As a result, it is possible to supply the refrigerant R having a low content of oil
A to the scroll compressor 13, and it is possible to decrease the amount of the oil
A in the refrigerant R which is compressed by the scroll compressor 13 and is discharged
therefrom. It is possible to decrease an oil circulation amount (OC%) in a system
including the two-stage compressor 1.
[0059] In addition, if the refrigerant R on the radially outer side comes into contact with
the restricting surface 62, the oil A in the refrigerant R is attached to the restricting
surface 62, and the refrigerant R in which the content of the oil A has decreased
is guided to the radially inner side by the restricting surface 62 and flows from
suction opening FCa into suction channel FC. Accordingly, in a state where the amount
of the oil A in the refrigerant R is decreased by the restricting surface 62, the
refrigerant R is supplied from the suction channel FC to the scroll compressor 13.
In this way, it is possible to decrease the amount of the oil A in the refrigerant
R which is compressed by the scroll compressor 13 and is discharged from the discharge
pipe 34 to the outside of the housing 11, and it is possible to decrease the oil circulation
amount (OC%) in the system.
[0060] In addition, the inflow restricting plate 61 is provided in the bearing casing 31b,
and thus, the restricting surface 62 can be provided in the bearing casing 31b. Accordingly,
compared to a case where a member corresponding to the inflow restricting plate 61
is attached to the housing 11, a welding work or the like with respect to the housing
11 is not required, and it is possible to very easily provide the restricting surface
62 in the bearing casing 31b. Accordingly, it is possible to effectively separate
the oil A in the refrigerant R from the refrigerant R while easily manufacturing the
two-stage compressor 1 having the restricting surface 62.
[0061] In addition, the oil return pipe 72 is provided, and thus, the oil which is used
to lubricate the high stage-side compression section is returned into the housing
11 through the oil return pipe 72. Accordingly, it is possible to further decrease
the amount of the oil A in the refrigerant R which is compressed by the scroll compressor
13 and is discharged therefrom. In addition, the oil return pipe 72 is provided on
the end portion on the radially outer side of the bearing casing 31b, and thus, the
oil return pipe 72 is provided at a position separated from the opening portion on
the radially inner side in the suction opening FCa on the radially inner side. Therefore,
the oil A which is returned from the oil return pipe 72 to the housing 11 can be prevented
from flowing from the suction opening FCa into the suction channel FC as it is. Accordingly,
it is possible to further decrease the amount of the oil A in the refrigerant R which
is compressed by the scroll compressor 13 and is discharged therefrom.
[0062] In addition, the refrigerant R having a high content of oil A which has passed through
the gap S between the housing 11 and the stator 39 in the region on the radially outer
side inside the housing 11 can be prevented from flowing from the portion between
the restricting surface 62 and the inner surface of the housing 11 into the scroll
compressor 13 as it is by the seal member 66. Therefore, it is possible to further
decrease the amount of the oil A in the refrigerant R which is compressed by the scroll
compressor 13 and is discharged therefrom.
[0063] In addition, even when the recessed portion 31c into which the wire 14a of the electric
motor 14 is inserted is formed in the bearing casing 31b, it is possible to seal the
gap among the recessed portion 31c, the wire 14a, and the inner surface of the housing
11 by the seal member 65. Accordingly, it is possible to prevent the refrigerant R
including the oil A from being supplied to the scroll compressor 13 through the gap
as it is.
[Second Embodiment]
[0064] Next, a two-stage compressor 80 according to a second embodiment of the present invention
will be described with reference to Figs. 4 and 5. In Fig. 4, for convenience of descriptions,
the wire 14a of the electric motor 14 and the oil return pipe 72 are not shown.
[0065] The same reference numerals are assigned to the components similar to those of the
second embodiment, and detail descriptions.
[0066] In the two-stage compressor 80 of the present embodiment, an inflow restricting plate
81 having a restricting surface 82 is different from the inflow restricting plate
61 of the first embodiment.
[0067] The inflow restricting plate 81 includes an annular portion 83 which is disposed
on the radially outer side along the inner surface of the housing 11 and is formed
in an annular shape about the axis X, and a conical portion 84 which is continuous
to the radially inner side of the annular portion 83 so as to be provided integrally
with the annular portion 83.
[0068] A lower surface of the annular portion 83 is a flat surface 86 which is formed in
an annular shape about the axis X. In addition, an outer surface of the conical portion
84 is an inclined surface 87 which is formed in a truncated conical shape about the
axis X. The inclined surface 87 is inclined downward from the flat surface 86 toward
the radially inner side.
[0069] In this way, the restricting surface 82 of the present embodiment includes the flat
surface 86 and the inclined surface 87. An inner edge portion 87a which is an end
edge on the radially inner side of the inclined surface 87 is positioned on the radially
inner side from the stator 39 and on the radially outer side from the bearing casing
31b and the rotary shaft 15.
[0070] In addition, in the present embodiment, the inner edge portion 87a of the inflow
restricting plate 81 is disposed at a position at which an intake amount of the refrigerant
R required in the scroll compressor 13 can be secured, that is, an opening area of
the suction opening FCa can be secured.
[0071] In the two-stage compressor 80 of the above-described present embodiment, the restricting
surface 82 has the inclined surface 87, and thus, it is possible to form an opening
portion OP which is formed in an annular shape about the axis X so as to extend downward
in the direction of the axis X from the suction opening FCa. Accordingly, compared
to the first embodiment, the area of the suction opening FCa which is open toward
the electric motor 14 can increase. Therefore, it is possible to secure a flow rate
of the refrigerant R flowing from the inside of the housing 11 into the suction channel
FC.
[0072] In addition, the refrigerant R having a high content of the oil A in the radially
outer side region in the housing 11 flows to the radially inner side along the flat
surface 86, and thereafter, collides with the inclined surface 87, and thus, the oil
A can be attached to the inclined surface 87. Accordingly, the refrigerant R can flow
into the suction channel FC in a state where the content of the oil A in the refrigerant
R further decreases so as to be supplied to the scroll compressor 13. As a result,
it is possible to further decrease the amount of the oil A in the refrigerant R which
is compressed by the scroll compressor 13 and is discharged to the outside of the
housing 11 and it is possible to further decrease the oil circulation amount (OC%)
in the system including the two-stage compressor 80.
[0073] In addition, in the present embodiment, the inner edge portion 87a on the radially
inner side of the inclined surface 87 is positioned on the radially inner side from
the stator 39, and thus, the restricting surface 82 extends to the position of the
rotor 38. Accordingly, the refrigerant R flowing through the radially inner side in
the housing 11 and the oil A in the refrigerant R come into contact with the rotor
38, and the refrigerant R in which the amount of the oil A is sufficiently decreased
by the rotor 38 can flow from the suction opening FCa into the suction channel FC.
[0074] In addition, the inner edge portion 87a of the inflow restricting plate 81 is disposed
at the position at which the intake amount of the refrigerant R required in the scroll
compressor 13 can be secured, and thus, it is possible to prevent compression efficiency
in the scroll compressor 13 from decreasing.
[0075] Hereinbefore, the embodiments of the present invention are described in detail with
reference to the drawings. However, the respective configurations and combinations
thereof in the respective embodiments are merely examples, and additions, omissions,
substations, and other modifications of configurations are possible within the scope
which does not depart from the present invention. In addition, the present invention
is not limited to the embodiments and are limited by only claims.
[0076] For example, the bearing casing 31b and each of the inflow restricting plates 61
and 81 may be integrated with each other. That is, each of the restricting surfaces
62 and 82 may be directly provided in the bearing casing 31b.
[0077] In addition, similarly to the second embodiment, in the first embodiment, the inner
edge portion 62a of the restricting surface 62 may be disposed on the radially inner
side from the stator 39. In addition, in this case, the position of the inner edge
portion 62a may be determined such that the intake amount of the refrigerant R required
in the scroll compressor 13 can be secured.
[0078] In addition, in the bearing casing 31b, instead of the recessed portion 31c, a through-hole
penetrating the bearing casing 31b in the direction of the axis X may be formed such
that the wire 14a is inserted into the through-hole so as to be disposed.
[0079] In addition, as shown in Fig. 6, an annular recessed portion 90 which is recessed
upward and is formed in an annular shape about the axis X may be provided in the restricting
surface 62A. According to the annular recessed portion, the refrigerant R on the radially
outer side comes into contact with the restricting surface 62A, and thus, the oil
A attached to the restricting surface 62A flows toward the radially inner side, and
it is possible to prevent the oil A from being sucked into the suction opening FCa.
The annular recessed portion 90 can be provided in any one of the restricting surface
62 of the first embodiment and the restricting surface 82 of the second embodiment.
[0080] In addition, in the housing 11, the rotary compressor 12 is provided as the low stage-side
compressor and the scroll compressor 13 is provided as the high stage-side compressor.
However, the present invention is not limited to this. For example, the scroll compressor
13 may be provided as the low stage-side compressor and the rotary compressor 12 may
be used as the high stage-side compressor. In addition, the scroll compressor 13 may
be provided on both the low stage side and the high stage side, or the rotary compressor
12 may be provided on both the low stage side and the high stage side. In addition,
a compressor other than the scroll compressor 13 and the rotary compressor 12 may
be provided.
[0081] Moreover, the restricting surfaces 62 and 82 may be provided in a two-stage compressor
which is used in a horizontal position so that the axis of the rotary shaft extends
in a horizontal direction.
Industrial Applicability
[0082] According to the hermetic two-stage compressor, the hermetic two-stage compressor
can be easily manufactured, and the oil in the gas can be effectively separated. Reference
Signs List
[0083]
1, 80: hermetic two-stage compressor
11: housing
12: rotary compressor (low stage-side compression section)
13: scroll compressor (high stage-side compression section)
14: electric motor
14a: wire
15: rotary shaft
21: main body portion
22: upper cover portion
23: lower cover portion
30: bearing device
31: upper bearing
31a: bearing
31b: bearing casing
31c: recessed portion (accommodation portion)
31d: bearing channel
32A, 32B: lower bearing
33: suction pipe
34: discharge pipe
37: through-hole
38: rotor
38a: oil separation plate
39: stator
41: eccentric shaft portion
42: piston rotor
44: cylinder
44a: suction hole
48: bolt
50: discharge cover
51: fixed scroll
52: end plate
52a: discharge hole
53: fixed lap
56: eccentric shaft portion
57: orbiting scroll
58: end plate
59: orbiting lap
60: bolt
61: inflow restricting plate
61a: notch
62, 62A: restricting surface
62a: inner edge portion
62b: outer edge portion
63: notch
65: seal member
66: seal member
72: oil return pipe (oil return section)
81: inflow restricting plate
82: restricting surface
83: annular portion
84: conical portion
86: flat surface
87: inclined surface
87a: inner edge portion
90: annular recessed portion
C1: compression chamber
C2: compression chamber
O1: oil storage
R: refrigerant
X: axis
A: oil
S: gap
FC: suction channel
FCa: suction opening
OP: opening portion
1. A hermetic two-stage compressor (1, 80) comprising:
a housing (11) which includes an oil storage (O1) inside the housing (11);
a rotary shaft (15) which is disposed in the housing (11) ;
a motor (14) which is disposed in the housing (11) so as to rotate the rotary shaft
(15) and includes a stator (39) which is provided on a radially outer side and a rotor
(39) which is provided on a radially inner side;
a low stage-side compression section (12) which is disposed on one side in an axial
direction of the rotary shaft (15) with respect to the motor (14) in the housing (11)
and is connected to the rotary shaft (15) so as to compress a gas;
a bearing device (30) which is disposed on the other side in the axial direction with
respect to the motor (14) in the housing (11) and includes a bearing (31a) which supports
the rotary shaft (15) and a bearing casing (31b) which supports the bearing (31a)
to the housing (11); and
a high stage-side compression section (13) which is disposed furhter on the other
side in the axial direction with respect to the bearing device (30) and further compresses
the gas discharged from the low stage-side compression section (12),
characterised in that the bearing casing (31b) includes
a plurality of suction channels (FC) which are provided to suck the gas into the high
stage-side compression section (13) and each of the plurality of the suction channels
(FC) include a suction opening (FCa) which is open to the one side in the axial direction,
and
a restricting surface (62) which is disposed between the suction opening (FCa) and
the motor (14) and is provided toward the radially inner side from an inner surface
of the housing (11) so as to restrict a flow of the gas to the suction opening (FCa)
on the radially outer side, wherein
the plurality of suction channels (FC) extend to be parallel to the axis (X) over
the entire region of the bearing casing (31b) in the direction of the axis (X) with
intervals to each other in the circumferential direction (X), and
wherein the restricting surface (62) includes a plurality of notches (63) which are
cut out from an end portion on the radially inner side toward the radially inner side
at a position corresponding to the suction opening (FCa) and only a position on the
radially inner side of the suction opening (FCa) is open toward the motor (14) .
2. The hermetic two-stage compressor (1) according to claim 1, further comprising:
an inflow restricting plate (61) which is fixed to the bearing casing (31b), is formed
in a plate shape, and includes the restricting surface (62) on the one side of the
axial direction.
3. A hermetic two-stage compressor (80) according to any one of claims 1 or 2,
wherein an inner edge portion (87a) on the radially inner side of the restricting
surface (82) is disposed at a position on the radially inner side of the stator (39),
and
wherein the restricting surface (82) closes a portion of the suction opening (FCa)
so as to secure an intake amount of the gas required in the high stage-side compression
section (13).
4. The hermetic two-stage compressor (1, 80) according to any one of claims 1 to 3, further
comprising:
a seal member (66) which is provided in a gap between an outer edge portion (62b)
on the radially outer side of the restricting surface and the inner surface of the
housing (11).
5. The hermetic two-stage compressor (1, 80) according to any one of claims 1 to 4, further
comprising:
an oil return section (72) which is provided at a position of an end portion on the
radially outer side in the bearing casing (31b), and causes the high stage-side compression
section (13) and the one side in the axial direction from the bearing casing (31b)
in the housing (11) to communicate with each other such that oil from the high stage-side
compression section (13) can flow through the oil return section (72).
6. A hermetic two-stage compressor (80) comprising:
a housing (11) which includes an oil storage (O1) inside the housing (11);
a rotary shaft (15) which is disposed in the housing (11) ;
a motor (14) which is disposed in the housing (11) so as to rotate the rotary shaft
(15) and includes a stator (39) which is provided on a radially outer side and a rotor
(39) which is provided on a radially inner side;
a low stage-side compression section (12) which is disposed on one side in an axial
direction of the rotary shaft (15) with respect to the motor (14) in the housing (11)
and is connected to the rotary shaft (15) so as to compress a gas;
a bearing device (30) which is disposed on the other side in the axial direction with
respect to the motor (14) in the housing (11) and includes a bearing (31a) which supports
the rotary shaft (15) and a bearing casing (31b) which supports the bearing (31a)
to the housing (11); and
a high stage-side compression section (13) which is disposed further on the other
side in the axial direction with respect to the bearing device (30) and further compresses
the gas discharged from the low stage-side compression section (12),
characterised in that the bearing casing (31b) includes
a plurality of suction channels (FC) which are provided to suck the gas into the high
stage-side compression section (13) and each of the plurality of suction channels
(FC) include a suction opening (FCa) which is open to the one side in the axial direction,
and
a restricting surface (82) which is disposed between the suction opening (FCa) and
the motor (14) and is provided toward the radially inner side from an inner surface
of the housing (11) so as to restrict a flow of the gas to the suction opening (FCa)
on the radially outer side,
wherein the plurality of suction channels (FC) extend to be parallel to the axis (X)
over the entire region of the bearing casing (31b) in the direction of the axis (X)
with intervals to each other in the circumferential direction (X), and
wherein the restricting surface (82) includes
a flat surface (86) which is provided on an end portion on the radially outer side
which is an inner surface side of the housing and is perpendicular to the axis to
be formed in an annular shape about the axis, and
an inclined surface (87) which is inclined toward the one side in the axial direction
from the flat surface (86) toward the radially inner side so as to be formed in a
truncated conical shape about the axis.
1. Hermetischer zweistufiger Kompressor (1, 80) umfassend:
ein Gehäuse (11), welches einen Ölspeicher (O1) innerhalb des Gehäuses (11) umfasst;
eine Drehwelle (15), die in dem Gehäuse (11) angeordnet ist;
einen Motor (14), der derart in dem Gehäuse (11) angeordnet ist, dass er die Drehwelle
(15) dreht, und einen Stator (39) umfasst, welcher auf einer radial äußeren Seite
vorgesehen ist, und einen Rotor (39) umfasst, welcher auf einer radial inneren Seite
vorgesehen ist;
einen niederdruckstufenseitigen Kompressionsabschnitt (12), welcher auf einer Seite
in einer axialen Richtung der Drehwelle (15) in Bezug auf den Motor (14) in dem Gehäuse
(11) angeordnet und mit der Drehwelle (15) verbunden ist, um ein Gas zu komprimieren;
eine Lagervorrichtung (30), welche auf der anderen Seite in der axialen Richtung in
Bezug auf den Motor (14) in dem Gehäuse (11) angeordnet ist und ein Lager (31a), welches
die Drehwelle (15) abstützt, und ein Lagergehäuse (31b) umfasst, welches das Lager
(31a) am Gehäuse (11) abstützt; und
einen hochdruckstufenseitigen Kompressionsabschnitt (13), welcher weiter auf der anderen
Seite in der axialen Richtung in Bezug auf die Lagervorrichtung (30) angeordnet ist
und das aus dem niederdruckstufenseitigen Kompressionsabschnitt (12) entladene Gas
weiter komprimiert,
dadurch gekennzeichnet, dass
das Lagergehäuse (31b) umfasst:
eine Vielzahl von Saugkanälen (FC), welche dafür vorgesehen sind, das Gas in den hochdruckstufenseitigen
Kompressionsabschnitt (13) zu saugen, wobei jeder der Vielzahl von Saugkanälen (FC)
eine Ansaugöffnung (FCa) aufweist, welche zu der einen Seite in der axialen Richtung
offen ist, und
eine Begrenzungsfläche (62), welche zwischen der Ansaugöffnung (FCa) und dem Motor
(14) angeordnet und von einer Innenfläche des Gehäuses (11) in Richtung der radial
inneren Seite vorgesehen ist, um eine Strömung des Gases zu der Ansaugöffnung (FCa)
auf der radial äußeren Seite zu begrenzen,
wobei sich die Vielzahl von Saugkanälen (FC) parallel zur Achse (X) über den gesamten
Bereich des Lagergehäuses (31b) in der Richtung der Achse (X) mit Abständen zueinander
in der Umfangsrichtung (X) erstreckt, und
wobei die Begrenzungsfläche (62) eine Vielzahl von Kerben (63) umfasst, welche von
einem Endabschnitt auf der radial inneren Seite in Richtung der radial inneren Seite
an einer Position ausgeschnitten sind, die der Ansaugöffnung (FCa) entspricht, und
nur eine Position auf der radial inneren Seite der Ansaugöffnung (FCa) in Richtung
des Motors (14) offen ist.
2. Hermetischer zweistufiger Kompressor (1) nach Anspruch 1, der weiter umfasst:
eine Zuflussbegrenzungsplatte (61), welche an dem Lagergehäuse (31b) befestigt ist,
in Plattenform ausgebildet ist und die Begrenzungsfläche (62) auf der einen Seite
der axialen Richtung umfasst.
3. Hermetischer zweistufiger Kompressor (80) nach einem der Ansprüche 1 oder 2,
wobei ein innerer Randabschnitt (87a) auf der radial inneren Seite der Begrenzungsfläche
(82) an einer Position an der radial inneren Seite des Stators (39) angeordnet ist,
und
wobei die Begrenzungsfläche (82) einen Teil der Ansaugöffnung (FCa) verschließt, um
eine in dem hochdruckstufenseitigen Kompressionsabschnitt (13) erforderliche Eintrittsmenge
des Gases sicherzustellen.
4. Hermetischer zweistufiger Kompressor (1, 80) nach einem der Ansprüche 1 bis 3, der
weiter umfasst:
ein Dichtungselement (66), welches in einem Spalt zwischen einem äußeren Randabschnitt
(62b) auf der radial äußeren Seite der Begrenzungsfläche und der Innenfläche des Gehäuses
(11) vorgesehen ist.
5. Hermetischer zweistufiger Kompressor (1, 80) nach einem der Ansprüche 1 bis 4, der
weiter umfasst:
einen Ölrücklaufabschnitt (72), welcher an einer Position eines Endabschnitts auf
der radial äußeren Seite in dem Lagergehäuse (31b) vorgesehen ist und bewirkt, dass
der hochdruckstufenseitige Kompressionsabschnitt (13) und die eine Seite in der axialen
Richtung von dem Lagergehäuse (31b) in das Gehäuse (11) derart miteinander kommunizieren,
dass das Öl aus dem hochdruckstufenseitigen Kompressionsabschnitt (13) durch den Ölrücklaufabschnitt
(72) fließen kann.
6. Hermetischer zweistufiger Kompressor (80) umfassend:
ein Gehäuse (11), welches einen Ölspeicher (O1) innerhalb des Gehäuses (11) umfasst;
eine Drehwelle (15), die in dem Gehäuse (11) angeordnet ist;
einen Motor (14), der derart in dem Gehäuse (11) angeordnet ist, dass er die Drehwelle
(15) dreht, und einen Stator (39) umfasst, welcher auf einer radial äußeren Seite
vorgesehen ist, und einen Rotor (39) umfasst, welcher auf einer radial inneren Seite
vorgesehen ist;
einen niederdruckstufenseitigen Kompressionsabschnitt (12), welcher auf einer Seite
in einer axialen Richtung der Drehwelle (15) in Bezug auf den Motor (14) in dem Gehäuse
(11) angeordnet und mit der Drehwelle (15) verbunden ist, um ein Gas zu komprimieren;
eine Lagervorrichtung (30), welche auf der anderen Seite in der axialen Richtung in
Bezug auf den Motor (14) in dem Gehäuse (11) angeordnet ist und ein Lager (31a), welches
die Drehwelle (15) abstützt, und ein Lagergehäuse (31b) umfasst, welches das Lager
(31a) am Gehäuse (11) abstützt; und
einen hochdruckstufenseitigen Kompressionsabschnitt (13), welcher weiter auf der anderen
Seite in der axialen Richtung in Bezug auf die Lagervorrichtung (30) angeordnet ist
und das aus dem niederdruckstufenseitigen Kompressionsabschnitt (12) entladene Gas
weiter komprimiert,
dadurch gekennzeichnet, dass
das Lagergehäuse (31b) umfasst:
eine Vielzahl von Saugkanälen (FC), welche dafür vorgesehen sind, das Gas in den hochdruckstufenseitigen
Kompressionsabschnitt (13) zu saugen, wobei jeder der Vielzahl von Saugkanälen (FC)
eine Ansaugöffnung (FCa) aufweist, welche zu der einen Seite in der axialen Richtung
offen ist, und
eine Begrenzungsfläche (82), welche zwischen der Ansaugöffnung (FCa) und dem Motor
(14) angeordnet und von einer Innenfläche des Gehäuses (11) in Richtung der radial
inneren Seite vorgesehen ist, um eine Strömung des Gases zu der Ansaugöffnung (FCa)
auf der radial äußeren Seite zu begrenzen,
wobei sich die Vielzahl von Saugkanälen (FC) parallel zur Achse (X) über den gesamten
Bereich des Lagergehäuses (31b) in der Richtung der Achse (X) mit Abständen zueinander
in der Umfangsrichtung (X) erstreckt, und
wobei die Begrenzungsfläche (82) umfasst:
eine flache Oberfläche (86), welche an einem Endabschnitt auf der radial äußeren Seite
vorgesehen ist, welche eine Innenflächenseite des Gehäuses ist und senkrecht zu der
Achse steht, die in einer Ringform um die Achse gebildet wird, und
eine geneigte Fläche (87), welche zu der einen Seite in der axialen Richtung von der
flachen Oberfläche (86) in Richtung der radial inneren Seite geneigt ist, um in einer
Kegelstumpfform um die Achse ausgebildet zu sein.
1. Compresseur hermétique à deux étages (1, 80) comprenant :
un boîtier (11) qui comprend un stockage d'huile (O1) à l'intérieur du boîtier (11)
;
un arbre rotatif (15) qui est disposé dans le boîtier (11) ;
un moteur (14) qui est disposé dans le boîtier (11) afin de faire tourner l'arbre
rotatif (15) et comprend un stator (39) qui est prévu sur le côté radialement externe
et un rotor (39) qui est prévu sur un côté radialement interne ;
une section de compression du côté de l'étage inférieur (12) qui est disposée d'un
côté dans une direction axiale de l'arbre rotatif (15) par rapport au moteur (14)
dans le boîtier (11) et est raccordée à l'arbre rotatif (15) afin de comprimer un
gaz ;
un dispositif de palier (30) qui est disposé de l'autre côté dans la direction axiale
par rapport au moteur (14) dans le boîtier (11) et comprend un palier (31a) qui supporte
l'arbre rotatif (15) et un carter de palier (31b) qui supporte le palier (31a) sur
le boîtier (11) ; et
une section de compression du côté de l'étage supérieur (13) qui est disposée plus
loin de l'autre côté dans la direction axiale par rapport au dispositif de palier
(30) et comprime en outre le gaz déchargé de la section de compression du côté de
l'étage inférieur (12),
caractérisé en ce que :
le carter de palier (31b) comprend :
une pluralité de canaux d'aspiration (FC) qui sont prévus pour aspirer le gaz dans
la section de compression du côté de l'étage supérieur (13) et chacun de la pluralité
de canaux d'aspiration (FC) comprend une ouverture d'aspiration (FCa) qui est ouverte
sur le premier côté dans la direction axiale, et
une surface de restriction (62) qui est disposée entre l'ouverture d'aspiration (FCa)
et le moteur (14) et est prévue vers le côté radialement interne à partir d'une surface
interne du boîtier (11) afin de limiter un écoulement du gaz vers l'ouverture d'aspiration
(FCa) sur le côté radialement externe,
dans lequel :
la pluralité de canaux d'aspiration (FC) s'étendent pour être parallèles à l'axe (X)
sur toute la région du carter de palier (31b) dans la direction de l'axe (X) avec
des intervalles entre eux dans la direction circonférentielle (X), et
dans lequel la surface de restriction (62) comprend une pluralité d'encoches (63)
qui sont découpées dans une partie d'extrémité sur le côté radialement interne vers
le côté radialement interne dans une position correspondant à l'ouverture d'aspiration
(FCa) et uniquement une position sur le côté radialement interne de l'ouverture d'aspiration
(FCa) est ouverte vers le moteur (14).
2. Compresseur hermétique à deux étages (1) selon la revendication 1, comprenant en outre
:
une plaque de restriction d'entrée (61) qui est fixée sur le carter de palier (31b),
est formée selon une forme de plaque, et comprend la surface de restriction (62) sur
le premier côté de la direction axiale.
3. Compresseur hermétique à deux étages (80) selon l'une quelconque des revendications
1 ou 2,
dans lequel une partie de bord interne (87a) sur le côté radialement interne de la
surface de restriction (82) est disposée dans une position sur le côté radialement
interne du stator (39), et
dans lequel la surface de restriction (82) ferme une partie de l'ouverture d'aspiration
(FCa) afin de fixer une quantité d'admission du gaz requise dans la section de compression
du côté de l'étage supérieur (13).
4. Compresseur hermétique à deux étages (1, 80) selon l'une quelconque des revendications
1 à 3, comprenant en outre :
un élément de joint d'étanchéité (66) qui est prévu dans un espace entre une partie
de bord externe (62b) sur le côté radialement externe de la surface de restriction
et la surface interne du boîtier (11).
5. Compresseur hermétique à deux étages (1, 80) selon l'une quelconque des revendications
1 à 4, comprenant en outre :
Une section de retour d'huile (72) qui est prévue dans une position d'une partie d'extrémité
sur le côté radialement externe dans le carter de palier (31b) et amène la section
de compression du côté de l'étage supérieur (13) et le premier côté dans la direction
axiale à partir du carter de palier (31b) dans le boîtier (11) à communiquer entre
eux de sorte que l'huile provenant de la section de compression du côté de l'étage
supérieur (13) peut s'écouler à travers la section de retour d'huile (72).
6. Compresseur hermétique à deux étages (80) comprenant :
un boîtier (11) qui comprend un stockage d'huile (O1) à l'intérieur du boîtier (11)
;
un arbre rotatif (15) qui est disposé dans le boîtier (11) ;
un moteur (14) qui est disposé dans le boîtier (11) afin de faire tourner l'arbre
rotatif (15) et comprend un stator (39) qui est prévu sur un côté radialement externe
et un rotor (39) qui est prévu sur un côté radialement interne ;
une section de compression du côté de l'étage inférieur (12) qui est disposée sur
un côté dans la direction axiale de l'arbre rotatif (15) par rapport au moteur (14)
dans le boîtier (11) et est raccordée à l'arbre rotatif (15) afin de comprimer un
gaz ;
un dispositif de palier (30) qui est disposé de l'autre côté dans la direction axiale
par rapport au moteur (14) dans le boîtier (11) et comprend un palier (31a) qui supporte
l'arbre rotatif (15) et un carter de palier (31b) qui supporte le palier (31a) sur
le boîtier (11) ; et
une section de compression du côté de l'étage supérieur (13) qui est disposée plus
loin de l'autre côté dans la direction axiale par rapport au dispositif de palier
(30) et comprime en outre le gaz déchargé par la section de compression du côté de
l'étage inférieur (12),
caractérisé en ce que :
le carter de palier (31b) comprend :
une pluralité de canaux d'aspiration (FC) qui sont prévus pour aspirer le gaz dans
la section de compression du côté de l'étage supérieur (13) et chacun de la pluralité
de canaux d'aspiration (FC) comprend une ouverture d'aspiration (FCa) qui est ouverte
vers le premier côté dans la direction axiale, et
une surface de restriction (82) qui est disposée entre l'ouverture d'aspiration (FCa)
et le moteur (14) et est prévue vers le côté radialement interne à partir d'une surface
interne du boîtier (11) afin de limiter un écoulement du gaz vers l'ouverture d'aspiration
(FCa) sur le côté radialement externe,
dans lequel la pluralité de canaux d'aspiration (FC) s'étendent pour être parallèles
à l'axe (X) sur toute la région du carter de palier (31b) dans la direction de l'axe
(X) avec des intervalles entre eux dans la direction circonférentielle (X), et
dans lequel la surface de restriction (82) comprend :
une surface plate (86) qui est prévue sur une partie d'extrémité sur le côté radialement
externe qui est un côté de surface interne du boîtier et est perpendiculaire à l'axe
à former selon une forme annulaire autour de l'axe, et
une surface inclinée (87) qui est inclinée vers le premier côté dans la direction
axiale de la surface plate (86) vers le côté radialement interne afin d'être formé
selon une forme tronconique autour de l'axe.