JP6071681B2 - Scroll compressor - Google Patents

Description

  The present invention relates to a scroll compressor.

A high-pressure shell-type vertical scroll compression containing a compression mechanism for compressing refrigerant, a drive unit for driving the compression mechanism and a refrigerating machine oil for lubricating the compression mechanism in a sealed container. The machine is generally known. In such a configuration, the compression mechanism section includes a fixed scroll having fixed plate-like spiral teeth and an orbiting scroll having swing plate-like spiral teeth that form a compression chamber facing the fixed plate-like spiral teeth. ing. The orbiting scroll can move in the axial direction, receives the pressure of the intermediate-pressure refrigerant introduced into the space on the back side, and is pressed against the fixed scroll to reduce the leakage loss of the refrigerant from the tooth tip during the compression operation. doing. In other words, a compliant frame is disposed on the back side of the orbiting scroll so that the thrust surface is in contact with the guide frame, and a guide frame is further disposed on the back surface of the compliant frame, and between the back surface of the compliant frame and the guide frame. A first intermediate pressure chamber is formed in the first. An intermediate pressure refrigerant is introduced into the first intermediate pressure chamber, the compliant frame is pushed up by the pressure of the refrigerant, and the swing scroll is pushed up through the thrust surface. The extraction method to the first intermediate pressure chamber is performed by extracting a part of the refrigerant that is being compressed by the compression mechanism through the communication hole provided in the compliant frame, and the position where the communication hole is formed. The pressure of the first intermediate pressure chamber can be changed depending on the extraction range, the pressure of the first intermediate pressure chamber is Pm1, the suction pressure is Ps, and the coefficient according to the position of the communication hole and the extraction range is β.
Pm1 = Ps × β (Formula 1)
It is a relationship.

Furthermore, a second intermediate pressure chamber is formed between the back surface of the orbiting scroll and the compliant frame, the inside is set to an intermediate pressure higher than the suction pressure, and a reaction force is obtained to obtain a thrust surface of the orbiting scroll and the compliant frame. Sliding loss at is reduced. That is, the intermediate pressure higher than the suction pressure in the second intermediate pressure chamber partially cancels the pressure contact force between the thrust surface of the orbiting scroll and the thrust bearing of the compliant frame, and the sliding loss of the orbiting scroll is reduced. To be reduced. The second intermediate pressure chamber and the suction space communicate with each other via a pressure reducing mechanism having a spring.
Pm2 = Ps + α (Formula 2)
(Pm2: pressure in the second intermediate pressure chamber, Ps: suction pressure, α: coefficient determined by spring force). Thus, the conventional scroll compressor implement | achieves the highly efficient compressor which can reduce a sliding loss, reducing the leakage loss of a compression mechanism part (for example, refer patent document 1, 2).

Japanese Unexamined Patent Publication No. 2000-161254 (FIG. 2) Japanese Unexamined Patent Publication No. 2000-329075 (FIGS. 1 to 3)

However, both of the scroll compressors described in Patent Documents 1 and 2 use a compliant frame as a method for extracting the first intermediate pressure chamber, by using a part of the intermediate pressure refrigerant that is being compressed by the compression mechanism. Since the air was extracted through, there were the following problems.
(A) When the compliant frame becomes unstable due to pressure fluctuation in the compression chamber during operation, the compliant frame is separated from the orbiting scroll, and the bleed into the first intermediate pressure chamber is It becomes unstable, the pressure does not increase, and the floating stability of the compliant frame cannot be obtained.
(B) When the compliant frame is unstable, the refrigerant compressed in the compression chamber escapes to the suction space, resulting in leakage loss.
(C) During steady operation, a pressure difference with the first intermediate pressure chamber is generated due to pressure fluctuation in the compression chamber, and so-called respiratory loss occurs in which the refrigerant moves back and forth between the compression chamber and the first intermediate pressure chamber.
(D) During steady operation, under low compression ratio conditions where the discharge pressure is low and the suction pressure is high, the first intermediate pressure becomes an intermediate pressure that is larger than necessary, and the force that pushes up the compliant frame increases and sliding loss increases.

  The problems (a) to (d) are that the second intermediate pressure chamber is formed by the back surface of the orbiting scroll and the compliant frame, and the second intermediate pressure chamber has a different route from the first intermediate pressure chamber. Even those with pressure refrigerant introduced still existed. In particular, when the compliant frame becomes unstable as in (a) and (b) and the compliant frame is separated from the swing scroll, not only the first intermediate pressure chamber but also the second intermediate pressure chamber. The pressure chamber was opened to the suction pressure space, the bleed into the first intermediate pressure chamber became unstable, the pressure did not increase, and the floating stability of the orbiting scroll could not be obtained.

  The present invention has been made in order to solve the above-described problems, and suppresses the compliant frame from being in an unstable state and ensures the extraction of air into the first intermediate pressure chamber. An object of the present invention is to obtain a scroll compressor capable of eliminating leakage loss and respiratory loss from the section.

  A scroll compressor according to the present invention stores a compression mechanism unit that compresses a refrigerant, a drive unit that drives the compression mechanism unit, and refrigeration oil that lubricates the compression mechanism unit in a sealed container. In the scroll compressor in which the compressed refrigerant is discharged into the sealed container and then discharged to the outside, the compression mechanism unit includes a fixed base plate and a fixed spiral tooth formed on one surface of the fixed base plate. Fixed scroll, the swinging spiral tooth that forms the compression chamber facing the fixed scroll tooth of the fixed scroll, the swinging base plate provided with the swinging spiral tooth, and the swinging spiral tooth of the swinging base plate are not installed Oscillating scroll provided with a boss part formed on the rear surface which is a surface, an oscillating bearing on the inner surface of the boss part, an Oldham mechanism for preventing the oscillating scroll from rotating, and an oscillating scroll which can move in the axial direction. Support the swing scroll back A compliant frame that forms a second intermediate pressure chamber on the side, a guide frame that supports the compliant frame and forms a first intermediate pressure chamber on the back side of the compliant frame, and a refrigerant discharged into the sealed container In addition, an oil supply hole through which the refrigeration oil passes is formed in the shaft center portion, and a crank portion that is slidably fitted to a rocking bearing of a boss portion of the rocking scroll is provided at one end portion of the main shaft portion, and driven. The shaft fixed to the motor rotor constituting the portion, the internal space of the boss portion and the first intermediate pressure chamber communicate with each other, and the pressure in the first intermediate pressure chamber is lower than the pressure in the internal space of the boss portion, The first pressure reducing mechanism for reducing the pressure so that the first intermediate pressure is higher than the suction pressure, the first intermediate pressure chamber and the second intermediate pressure chamber communicate with each other, and the pressure in the second intermediate pressure chamber is the first intermediate pressure chamber. Lower than the first intermediate pressure of inhalation And a second pressure reducing mechanism for reducing the pressure so that the second intermediate pressure becomes higher. The compliant frame receives the first intermediate pressure in the first intermediate pressure chamber and presses the orbiting scroll against the fixed scroll. The pressing force on the thrust receiving surface of the compliant frame is reduced by receiving the second intermediate pressure in the intermediate pressure chamber.

  According to the scroll compressor of the present invention, the internal space of the boss portion and the first intermediate pressure chamber communicate with each other, and the pressure in the first intermediate pressure chamber is lower than the pressure in the internal space of the boss portion and is higher than the suction pressure. The first pressure reducing mechanism for reducing the pressure to a high first intermediate pressure communicates with the first intermediate pressure chamber and the second intermediate pressure chamber, and the pressure in the second intermediate pressure chamber is the first intermediate pressure chamber in the first intermediate pressure chamber. And a second pressure reducing mechanism for reducing the pressure to a second intermediate pressure lower than the suction pressure and higher than the suction pressure, and the compliant frame receives the first intermediate pressure in the first intermediate pressure chamber and fixes the orbiting scroll. Since the pressing force on the thrust receiving surface of the compliant frame is reduced by being pressed against the scroll and receiving the second intermediate pressure in the second intermediate pressure chamber, the compliant frame is subject to pressure fluctuations in the compression mechanism section. Accompanying instability Can be suppressed from becoming a state, stable flying can be obtained. For this reason, a sliding loss can be reduced, reducing the leakage loss from the crevice tooth gap of a spiral tooth. Moreover, since it is not extraction from a compression mechanism part, the respiratory loss accompanying the pressure fluctuation of a compression mechanism part can be reduced, and compression efficiency can be improved.

It is a longitudinal section showing the whole scroll compressor composition concerning an embodiment of the present invention. It is principal part sectional drawing which shows the Oldham key and Oldham keyway by the side of the fixed scroll of the scroll compressor which concerns on embodiment of this invention. It is principal part sectional drawing which shows the Oldham key and Oldham keyway by the side of the rocking scroll of the scroll compressor which concerns on embodiment of this invention. It is principal part sectional drawing which shows the flow of the refrigerating machine oil supplied to the compression mechanism part of the scroll compressor which concerns on embodiment of this invention. It is principal part sectional drawing which shows the 1st intermediate pressure chamber of the scroll compressor which concerns on embodiment of this invention, and the external space (2nd intermediate pressure chamber) of a boss | hub part. It is principal part sectional drawing which shows the slider provided in the crank part of the axis | shaft of the scroll compressor which concerns on embodiment of this invention, and the bearing of an orbiting scroll. It is a schematic diagram which shows operation | movement of the slider provided in the crank part of the axis | shaft of the scroll compressor which concerns on embodiment of this invention, and the bearing part of an orbiting scroll. It is a schematic diagram which shows operation | movement of the slider provided in the crank part of the axis | shaft of the scroll compressor which concerns on embodiment of this invention, and the bearing part of an orbiting scroll.

  FIG. 1 is a longitudinal sectional view showing the overall configuration of a scroll compressor according to an embodiment of the present invention. Note that the drawings (including other drawings) are schematically drawn, and the present invention is not limited to the illustrated forms.

In FIG. 1, a scroll compressor 100 is formed at a hermetic container 10, a compression mechanism unit disposed at the top of the hermetic container 10, a drive unit disposed at the center of the hermetic container 10, and the bottom of the hermetic container 10. An oil reservoir.
The compression mechanism is formed of a fixed scroll 1 and a swing scroll 2 fixed to the hermetic container 10. The drive unit includes an electric motor stator 7 fixed to the hermetic container 10 and an electric motor rotor 8 that is rotatably disposed inside the electric motor stator 7.

[Configuration of fixed scroll]
FIG. 2 is a cross-sectional view of the main part showing the Oldham key and Oldham key groove on the fixed scroll side of the scroll compressor according to the embodiment of the present invention.
1 and 2, the fixed scroll 1 has a disk-shaped fixed base plate 1a whose outer periphery is fastened to a guide frame 5 by bolts (not shown). A plate-like spiral tooth (hereinafter referred to as “fixed spiral tooth”) 1b is formed on one surface (lower side in FIG. 1) of the fixed base plate 1a. A refrigerant gas suction pipe 10a is press-fitted through the sealed container 10 into the side surface of the fixed spiral tooth 1b. A discharge port 1e for discharging the compressed gas is provided at the center of the fixed base plate 1a. The discharge gas is discharged from the discharge port 1e into the sealed container 10 and supplied to the external refrigeration cycle via the discharge pipe 10b. Two pairs of Oldham key grooves 1c are formed substantially in a straight line on the outer peripheral portion of the fixed spiral tooth 1b. A pair of fixed-side Oldham keys 9c of an Oldham mechanism 9 described later is fitted into the Oldham key groove 1c so as to be freely slidable.

[Configuration of rocking scroll]
The oscillating scroll 2 has a plate-like spiral tooth (hereinafter referred to as an “oscillating spiral tooth”) substantially the same shape as the fixed spiral tooth 1b on one surface (upper side in FIG. 1) of the disk-like rocking base plate 2a. 2b is formed. A compression chamber having a relatively variable volume is formed between the fixed spiral tooth 1b and the swing spiral tooth 2b. A hollow cylindrical boss 2d is formed at the center of the surface opposite to the swing spiral tooth 2b of the swing base plate 2a (lower side in FIG. 1), and on the inner surface of the boss 2d, A rocking bearing 2h is formed.

  A thrust surface 2f is formed on the outer peripheral portion of the same surface (lower side in FIG. 1) as the boss portion 2d of the swing base plate 2a. The thrust surface 2 f can be slidably pressed against the thrust receiving surface 3 a of the compliant frame 3.

FIG. 3 is a cross-sectional view of the main part showing the Oldham key and Oldham key groove on the swing scroll side of the scroll compressor according to the embodiment of the present invention.
1 and 3, a pair of Oldham key grooves 2 c having a phase difference of approximately 90 degrees with the Oldham key groove 1 c of the fixed scroll 1 are formed in a substantially straight line on the outer peripheral portion of the swing base plate 2 a of the swing scroll 2. Has been. A pair of swing-side Oldham keys 9b of an Oldham mechanism 9 described later is engaged with the Oldham key groove 2c so as to be slidable in a reciprocating manner.

[Configuration of guide frame and compliant frame]
FIG. 4 is a cross-sectional view of the main part showing the flow of refrigerating machine oil supplied to the compression mechanism of the scroll compressor according to the embodiment of the present invention. FIG. 5 is a cross-sectional view of the main part showing the first intermediate pressure chamber and the external space (second intermediate pressure chamber) of the boss portion of the scroll compressor according to the embodiment of the present invention.
The guide frame 5 forms an intermediate pressure chamber on the back side of the orbiting scroll 2. The intermediate pressure chamber is divided by the compliant frame 3 into two upper and lower intermediate pressure chambers, that is, a second intermediate pressure chamber (the external space 2i of the boss portion) and a first intermediate pressure chamber 5e. A compliant frame 3 that is an axially moving frame is a combination of a large-diameter cylindrical portion and a small-diameter cylindrical portion as shown in FIG. A surface 3a is formed. Further, on the outside of the thrust receiving surface 3a, that is, on the outer periphery of the large-diameter cylindrical portion, a flange-like surface (hereinafter referred to as “projection surface”) 3h is formed, and the Oldham of the Oldham mechanism 9 is formed on the projection surface 3h. The mechanism annular portion 9a is placed and reciprocates.

  Further, as shown in FIG. 4, the projecting surface 3h has a communication hole (functioning as a post-regulator valve flow passage) 3i that communicates the base plate outer peripheral space 2k and the compliant frame outer space 5f, as shown in FIG. And the compliant frame outer space 5f are communicated with each other.

  Further, as shown in FIG. 4, in the compliant frame 3, the first pressure reducing mechanism 3r is housed in a refrigerant flow path provided between the internal space 2g of the boss portion 2d and the first intermediate pressure chamber 5e. The first decompression mechanism 3r may be decompressed by a capillary effect as in the spiral structure shown in FIG. 5, or may be decompressed by a multistage orifice. When providing a spiral structure, a spiral groove may be formed on the compliant frame 3 side.

  Further, as shown in FIGS. 4 and 5, the compliant frame 3 houses a second intermediate pressure adjusting valve 3o, a valve presser 3q, and a second intermediate pressure adjusting spring 3p, which are on-off valves of the first intermediate pressure chamber 5e. A second decompression mechanism 3n is provided. The second intermediate pressure adjusting spring 3p is housed in a compressed state.

  Further, as shown in FIGS. 4 and 5, the compliant frame 3 includes a third intermediate pressure adjusting valve 3k, a valve presser 3m, A third pressure reducing mechanism 3j that houses the intermediate pressure adjusting spring 3l is provided. The third intermediate pressure adjustment spring 31 is housed in a compressed state in the same manner as the second intermediate pressure adjustment spring 3p.

  An upper fitting cylindrical surface 5a is formed on the fixed scroll 1 side (upper side in FIG. 1) of the inner side surface of the guide frame 5, and an upper fitting cylindrical surface 3b formed on the outer peripheral surface of the compliant frame 3 is fitted. doing.

  A lower fitting cylindrical surface 5b is formed on the inner side of the guide frame 5 on the electric motor side (lower side in FIG. 1), and a lower fitting cylindrical surface 3c formed on the outer peripheral surface of the compliant frame 3 is fitted. Match.

  The first intermediate pressure chamber 5e formed by the inner side surface of the guide frame 5 and the outer side surface of the compliant frame 3 is partitioned by a ring-shaped upper seal material 11a and lower seal material 11b. Here, two ring-shaped seal grooves for accommodating the upper seal material 11 a and the lower seal material 11 b are formed on the outer peripheral surface of the compliant frame 3. The seal grooves are formed on the inner peripheral surface of the guide frame 5. It may be formed.

  Also, the space on the outer peripheral side of the thrust receiving surface 3a surrounded by the swing base plate 2a of the swing scroll 2 and the compliant frame 3, that is, the base plate outer peripheral space 2k shown in FIG. It is a suction pressure space.

  On the other hand, the internal space 2g of the boss portion 2d of the orbiting scroll 2 shown in FIGS. 4 and 5 is connected to an oil supply hole 4g which is a through hole formed in the shaft center portion of the shaft 4, and serves as a discharge pressure. The compliant frame 3 accommodates an end face seal material 13 which is a partition between the internal space 2g of the boss portion 2d under discharge pressure and the external space 2i of the boss portion 2d reduced to the second intermediate pressure as described later. An end face seal groove 3s is provided, and the end face seal material 13 is accommodated in the end face seal groove 3s. The end surface sealing material 13 can slide in pressure contact with the lower end surface of the boss portion 2d during steady operation. In addition, the groove | channel which accommodates the end surface sealing material 13 may be provided in the lower end surface side of the boss | hub part 2d.

[Axis configuration]
A crank portion 4a is formed at the end of the shaft 4 on the side of the orbiting scroll 2 (lower side in FIG. 1), and is slidably fitted to the inner peripheral surface of the orbiting bearing 2h of the orbiting scroll 2. Yes.

  A main shaft portion 4c that is rotatably fitted to the main bearing 3d and the auxiliary main bearing 3e of the compliant frame 3 is formed below the crank portion 4a. The main shaft portion 4c is formed with a horizontal hole 4h that communicates from the oil supply hole 4g of the shaft center portion to the lower end surface side of the main bearing 3d so that the refrigerating machine oil 10d that is lubricating oil can be supplied to the main bearing 3d through the horizontal hole 4h. It has become.

  Further, the other end portion of the shaft 4 is formed with a sub-shaft portion 4d that is rotatably fitted to the sub-bearing 6a of the sub-frame 6, and an electric motor rotor 8 is provided between the sub-shaft portion 4d and the main shaft portion 4c. It is shrink-fitted.

  Further, an oil pipe 4 i is press-fitted into the lower end surface of the shaft 4 and is surrounded by a cylindrical vortex ripple prevention wall 14. The oil pipe 4 i sucks up the refrigerating machine oil 10 d accumulated at the bottom of the sealed container 10 using a differential pressure generated by the pressure of the refrigerant discharged into the sealed container 10. The vortex ripple prevention wall 14 prevents the vortex generated with the rotation of the oil pipe 4i from spreading to the periphery and affecting the suction of the refrigerating machine oil 10d.

  The crank portion 4a, together with the motor rotor 8, provides a revolving motion to the orbiting scroll 2 by rotating together with the shaft 4 when the shaft 4 rotates.

[Slider configuration]
FIG. 6 is a cross-sectional view of the main part showing the slider and the bearing of the orbiting scroll provided in the crank part of the shaft of the scroll compressor according to the embodiment of the present invention. 7 and 8 are schematic views showing the operation of the slider provided on the crank portion of the shaft of the scroll compressor and the bearing portion of the orbiting scroll according to the embodiment of the present invention. As described above, when the shaft 4 rotates together with the motor rotor 8, the crank portion 4a rotates integrally with the shaft 4 to give the orbiting scroll a revolving motion. At this time, as shown in FIG. 6, the slider 12 is disposed so as to be slidably fitted between the crank portion 4a of the shaft 4 and the rocking bearing 2h of the rocking scroll 2, as shown in FIG. Alternatively, a gap g may be provided between the crank portion 4 a and the slider 12. The rotational motion of the crank portion 4a is transmitted to the slider 12 via the inner peripheral portion 12b of the slider 12, and a revolving motion is given to the orbiting scroll 2 by the rotational motion.

  FIG. 7 shows the slider 12 with a gap g formed between the end of the crank portion 4a in the eccentric direction and the crank portion 4a. By arranging the gap g in this way, the slider 12 slides by an amount corresponding to the gap g in the eccentric direction of the orbiting scroll 2 in a plane perpendicular to the axis of the main shaft portion 4c with respect to the crank portion 4a. Can do. Since the rocking bearing 2h is engaged with the outer peripheral portion 12a of the slider 12, the rocking scroll 2 slides in the eccentric direction due to the centrifugal force of the rocking scroll 2 itself. Then, the side surface of the oscillating spiral tooth 2b of the oscillating scroll 2 is brought into contact with the side surface of the fixed spiral tooth 1b of the fixed scroll 1, and the radial gap of the compression chamber is sealed, thereby reducing leakage loss.

  Further, as shown in FIG. 8, the eccentric direction of the orbiting scroll 2 (= the eccentric direction of the crank portion 4a) and the direction in which the slider 12 slides may be different. That is, a gap g is formed between the end of the slider 12 that is inclined at a certain angle from the eccentric direction of the crank portion 4a (= the eccentric direction of the orbiting scroll 2) in the counter-rotating direction and the crank portion 4a. Also good. By arranging the gap g in this way, the slider 12 can slide in a direction inclined by a certain angle in the eccentric direction of the crank portion 4 a, that is, in a direction inclined by a certain angle in the anti-revolution direction of the orbiting scroll 2. A part (component force) of the reaction force of the force for compressing the refrigerant gas can be applied as a force for moving the slider 12 forward in the centrifugal direction. For this reason, even in the operating condition in which the centrifugal force of the orbiting scroll 2 itself is small at the time of low speed operation and a gap is generated between the side surfaces of the swirl teeth of the fixed scroll 1 and the orbiting scroll 2, The 2b side surface can be pressed against the fixed spiral tooth 1b side surface, the gap in the radial direction of the compression chamber can be sealed, and the leakage loss can be reduced.

[Operation of scroll compressor]
Next, the operation of the scroll compressor 100 according to this embodiment will be described.
As described above, the compression mechanism unit has the fixed scroll 1 and the swing scroll 2, and the compression chamber is formed by the fixed spiral tooth 1b and the swing spiral tooth 2b. The compression chamber moves while reducing its volume from the outer peripheral side to the inner peripheral side by the swing of the swing scroll 2.

  Therefore, during steady operation, the refrigerant sucked from the suction pipe 10a is compressed in the compression chamber, becomes refrigerant gas, is discharged into the sealed container 10 from the discharge port 1e, and enters the external refrigeration cycle via the discharge pipe 10b. Supplied. At this time, since the sealed container space 10 c becomes a discharge pressure space of the discharge gas atmosphere, a differential pressure is generated between the discharge pressure space and the oil supply hole 4 g of the shaft 4, and this differential pressure causes the bottom of the sealed container 10. The refrigerating machine oil 10d is sucked up by the oil pipe 4i, and flows upward in the oil supply hole 4g of the shaft 4 in FIG.

  Then, as indicated by an arrow in FIG. 4, the refrigerating machine oil 10d, which is the lubricating oil guided to the internal space 2g of the boss portion 2d, is supplied to the gap between the swing bearing 2h and the crank portion 4a, and then the first The pressure is reduced by the pressure reducing mechanism 3r, becomes a “first intermediate pressure” that is lower than the discharge pressure in the sealed container 10 and higher than the suction pressure, and flows into the first intermediate pressure chamber 5e.

  As another path, the refrigerating machine oil 10d in the oil supply hole 4g is guided from the horizontal hole 4h of the shaft 4 to the lower end surface of the main bearing 3d as shown in FIG. The pressure is reduced through the first pressure reducing mechanism 3r and flows into the first intermediate pressure chamber 5e.

  The refrigerating machine oil 10d that has become the first intermediate pressure in the first intermediate pressure chamber 5e (generally a two-phase flow of gas refrigerant and refrigerating machine oil due to the foaming of the refrigerant dissolved in the refrigerating machine oil) 10d 2 The pressure is reduced by the pressure reducing mechanism 3n and flows into the external space 2i of the boss portion 2d which is the second intermediate pressure chamber. That is, the refrigerating machine oil 10d having reached the first intermediate pressure overcomes the force applied by the second intermediate pressure adjusting spring 3p when passing through the second pressure reducing mechanism 3n, and is a second intermediate pressure adjusting valve that is an on-off valve. 3o is pushed up to become a “second intermediate pressure” which is lower than the first intermediate pressure and higher than the suction pressure, and flows into the external space 2i of the boss portion 2d.

  The refrigerating machine oil 10d that has become the second intermediate pressure in the external space 2i of the boss portion 2d is further depressurized by the third decompression mechanism 3j, becomes suction pressure, flows into the compliant frame external space 5f, and then passes through the communication hole 3i. And discharged to the inside of the Oldham mechanism annular portion 9a. That is, when the refrigerating machine oil 10d having reached the second intermediate pressure passes through the third pressure reducing mechanism 3j, the refrigeration oil 10d overcomes the force applied by the third intermediate pressure adjusting spring 3l and becomes a third intermediate pressure adjusting valve that is an on-off valve. 3k is pushed up and discharged from the compliant frame outer space 5f to the inside of the Oldham mechanism annular portion 9a through the communication hole 3i.

  The refrigerating machine oil 10d that has become the second intermediate pressure in the external space 2i of the boss portion 2d slides between the thrust surface 2f of the orbiting scroll 2 and the thrust receiving surface 3a of the compliant frame 3 as another path. After the oil is supplied to the part, that is, after the oil is supplied to the oil supply passage formed by the thrust surface 2f of the orbiting scroll 2 and the surface of the thrust receiving surface 3a of the compliant frame 3, the oil is discharged inside the Oldham mechanism annular part 9a. The

  The refrigerating machine oil 10d discharged from these oils is supplied to the sliding surfaces of the Oldham mechanism annular portion 9a of the Oldham mechanism 9 and the sliding surfaces of the swinging Oldham key 9b and the fixed Oldham key 9c. The outer space 2k is opened.

The second intermediate pressure (Pm2) in the external space 2i of the boss portion 2d is equal to the pressure (Ps) in the compliant frame external space 5f, the spring force of the third intermediate pressure adjusting spring 3l of the third pressure reducing mechanism 3j, and the third intermediate pressure. It is controlled by the following (Equation 3) as the sum of the pressure (α2) determined by the intermediate pressure exposure area of the pressure regulating valve 3k.
Pm2 = Ps + α2 (Formula 3)
Note that the pressure (Ps) in the outer space of the compliant frame is the suction atmosphere pressure.

Similarly, the first intermediate pressure (Pm1) in the first intermediate pressure chamber 5e is the second intermediate pressure (Pm2) in the external space 2i of the boss portion 2d, the spring force of the second pressure reducing mechanism 3n, and the second intermediate pressure adjustment. It is controlled by the following (Equation 4) as the sum of the pressure (α1) determined by the intermediate pressure exposure area of the valve 3o.
Pm1 = Pm2 + α1 (Formula 4)

The compliant frame 3 has a force (F1) caused by the second intermediate pressure Pm2 in the external space 2i of the boss 2d and a pressing force (F2) received from the orbiting scroll 2 via the thrust receiving surface 3a. A force (F1 + F2) obtained by adding the two acts as a downward force.
On the other hand, the compliant frame 3 is exposed to the force (F3) caused by the first intermediate pressure (Pm1) of the first intermediate pressure chamber 5e and the discharge pressure atmosphere of the sealed container space 10c in the lower fitting cylindrical surface 3c. The force (F3 + F4), which is the sum of the force (F4) caused by the discharge pressure acting on the lower end surface portion, acts as an upward force.
In the steady operation, the upward force is set to be larger than the downward force ((F1 + F2) <(F3 + F4)).

  As described above, the compliant frame 3 guides the upper fitting cylindrical surface 3b to the upper fitting cylindrical surface 5a of the guide frame 5 and the lower fitting cylindrical surface 3c to the lower fitting cylindrical surface 5b of the guide frame 5. It can slide in the axial direction. Therefore, during a steady operation in which the upward force is greater than the downward force, the compliant frame 3 is lifted from the guide frame 5 to the fixed scroll 1 side (upward in FIG. 1).

  The orbiting scroll 2 that receives the pressing force from the compliant frame 3 via the thrust receiving surface 3a is also lifted upward. As a result, the tooth tip and the tooth bottom of the orbiting scroll 2 come into contact with and slide on the tooth bottom and the tooth tip of the fixed scroll 1, respectively. 4 and 5 show the state of the orbiting scroll 2 and the compliant frame 3 during the steady operation.

  Further, when the scroll compressor 100 is in an excessive period such as when the compressor is started or when the internal pressure of the compression chamber rises abnormally, the internal pressure of the compression chamber causes the fixed spiral tooth 1b and the swinging spiral tooth 2b to be separated from each other in the axial direction. A gap is formed between the tooth tip and the tooth bottom that are in contact with each other and are in a relief state.

[Function of end face seal material]
As described above, the end surface sealing material 13 is accommodated in the end surface sealing groove 3s of the compliant frame 3, and the boss portion in which the discharge pressure in the internal space 2g of the boss portion 2d is the second intermediate pressure during the steady operation. Inflow to the external space 2i of 2d is prevented.

  At the time of startup, a gap 13b may be generated between the end surface sealing material 13 and the lower end surface of the boss portion 2d of the orbiting scroll 2 as shown in FIG. However, since the speed of the refrigerant flowing through the lower space 13a of the end face seal material 13 is slower than the speed of the refrigerant flowing through the gap 13b, the end face seal material 13 has negative pressure on the upper side to obtain buoyancy. Therefore, the end surface sealing material 13 is pressed against the lower end surface of the boss portion 2d, and functions as an original sealing material.

  Note that a backup ring or the like may be disposed in the lower space 13a of the end surface sealing material 13 in order to improve the sealing performance at the time of activation.

  Thus, the compliant frame 3 can move in the axial direction, and the resultant force applied in the axial direction acts upward and rises upward during steady operation. Furthermore, since the orbiting scroll 2 also floats upward via the thrust receiving surface 3a, the tooth tip and the tooth bottom of the orbiting spiral tooth 2b are in contact with the tooth bottom and the tooth tip of the fixed spiral tooth 1b of the fixed scroll 1, respectively. Compressive motion in the state. Therefore, leakage of the refrigerant in the compression chamber in the middle of compression or the discharge pressure refrigerant at the center of the compression chamber from the axial clearance of the fixed spiral tooth 1b of the fixed scroll 1 and the swing spiral tooth 2b of the swing scroll 2 is prevented. Compression efficiency is improved.

  In order to float the compliant frame 3 in the axial direction, the first intermediate pressure (Pm1) is introduced into the first intermediate pressure chamber 5e, but the refrigerant gas flow path for introducing the first intermediate pressure has a discharge gas atmosphere. Since it is connected in series from the space through the first pressure reducing mechanism 3r, there is no portion where leakage occurs in the refrigerant gas path, and the compressor efficiency is improved.

  In addition, since the discharge pressure is used as a method for introducing the first intermediate pressure into the first intermediate pressure chamber 5e, there is no need to extract the refrigerant gas during the compression of the compression mechanism portion as in the conventional case, and the refrigerant in the compression chamber Gas leakage loss is reduced. Further, there is no need to form bleed holes for introducing the first intermediate pressure from the compression chamber of the compression mechanism portion to the first intermediate pressure chamber 5e as in the prior art, and the oscillating scroll 2 and compliant frame 3 do not have to be formed. Leakage of the refrigerant gas into the gap between the thrust surface 2f of the dynamic scroll 2 and the thrust receiving surface 3a of the compliant frame 3 can be eliminated. For this reason, there is no respiratory loss in the first intermediate pressure chamber 5e due to pressure fluctuation in the compression chamber, and the compressor efficiency is improved.

  Conventionally, as described above, the intermediate pressure is introduced into the first intermediate pressure chamber 5e directly from the compression chamber of the compression mechanism section through the communication holes formed in the orbiting scroll 2 and the compliant frame 3. Since the compliant frame 3 is unstable at the time of start-up, the thrust surface 2f of the orbiting scroll 2 is separated from the thrust receiving surface 3a, and the bleed cannot be performed. In some cases, a stable levitation of 3 could not be obtained.

  However, in the scroll compressor 100 of the present embodiment, since the first intermediate pressure is introduced into the first intermediate pressure chamber 5e through the internal space 2g of the boss portion 2d, stable bleed can be performed, The flying stability of the compliant frame 3 can be obtained.

  Further, in the related art, the control of Pm1, which is the pressure (first intermediate pressure) in the first intermediate pressure chamber 5e, is controlled by a predetermined position that is substantially determined by the position of the compression chamber that is in communication as described in the above-described equation 1. Depends on the magnification β. In such a control, the first intermediate pressure Pm1 rises more than necessary under conditions where the discharge pressure is low and the suction pressure is high (a condition that greatly affects the APF (year-round energy consumption efficiency) performance). The previous pressing force increases and sliding loss increases.

  However, in the scroll compressor 100 of the present embodiment, the control of the first intermediate pressure Pm1 is performed by the spring force (Pm2) of the second pressure reducing mechanism 3n and the second intermediate pressure adjusting valve as described in the above-described equation 4. Since the control is based on the sum of the predetermined pressure (α1) determined by the intermediate pressure exposure area of 3o, the first intermediate pressure does not increase more than necessary even if the suction pressure increases, and the spiral The pressing force of the tooth tip can be maintained in an appropriate state, and the compressor efficiency is improved as the sliding loss is reduced. That is, it is possible to suppress the compliant frame 3 from becoming unstable due to pressure fluctuations in the compression mechanism portion, to obtain a stable levitation property, and to reduce the leakage loss from the tooth tip gap of the spiral tooth while sliding. Dynamic loss can be reduced.

  1 fixed scroll, 1a fixed base plate, 1b fixed spiral tooth, 1c Oldham keyway, 1e discharge port, 2 swinging scroll plate, 2a swinging base plate, 2b swinging spiral tooth, 2c Oldham keyway, 2d boss part, 2f thrust surface 2g Internal space, 2h Rocking bearing, 2i External space (second intermediate pressure chamber), 2k Base plate outer space, 3 Compliant frame, 3a Thrust receiving surface, 3b Upper fitting cylindrical surface, 3c Lower fitting cylinder Surface, 3d main bearing, 3e auxiliary main bearing, 3h projecting surface, 3i communication hole, 3j third pressure reducing mechanism, 3k third intermediate pressure adjusting valve, 3l third intermediate pressure adjusting spring, 3m valve presser, 3n second pressure reducing mechanism 3o 2nd intermediate pressure adjusting valve, 3p 2nd intermediate pressure adjusting spring, 3q valve retainer, 3r first pressure reducing mechanism, 3s end face seal groove, 4 shaft, 4a crank portion, 4c main shaft portion, 4 Secondary shaft part, 4g Oil supply hole, 4h Side hole, 4i Oil pipe, 5 Guide frame, 5a Upper fitting cylindrical surface, 5b Lower fitting cylindrical surface, 5e First intermediate pressure chamber, 5f Compliant frame outer space, 6 Subframe , 6a Sub bearing, 7 Motor stator, 8 Motor rotor, 9 Oldham mechanism, 9a Oldham mechanism annular part, 9b Oscillating side Oldham key, 9c Fixed side Oldham key, 10 Sealed container, 10a Suction pipe, 10b Discharge pipe, 10c Sealed Container space, 10d Refrigerating machine oil, 11a Upper seal material, 11b Lower seal material, 12 Slider, 12a Outer peripheral portion, 12b Inner peripheral portion, 13 End face seal material (seal material), 13a, Lower space of end face seal material, 13b Gap, 14 Swelling prevention wall, 100 Scroll compressor, Pm1 first intermediate pressure, Pm2 second intermediate pressure, g Gaps.

Claims (6)

In the closed container, a compression mechanism portion that compresses the refrigerant, a drive portion that drives the compression mechanism portion, and refrigeration oil that lubricates the compression mechanism portion, and the refrigerant compressed by the compression mechanism portion is In the scroll compressor discharged into the sealed container and then discharged to the outside,
The compression mechanism is
A fixed scroll having a fixed base plate and a fixed spiral tooth formed on one surface of the fixed base plate;
An oscillating spiral tooth that forms a compression chamber facing the fixed spiral tooth of the fixed scroll, an oscillating base plate on which the oscillating spiral tooth is installed, and the oscillating spiral tooth on the oscillating base plate is not installed A boss part formed on the back surface, which is a surface, and an orbiting scroll having an orbiting bearing on the inner surface of the boss part;
An Oldham mechanism for preventing rotation of the swing scroll;
A compliant frame that can move in the axial direction, supports the orbiting scroll, and forms a second intermediate pressure chamber on the back side of the orbiting scroll;
A guide frame that supports the compliant frame and forms a first intermediate pressure chamber on the back side of the compliant frame;
An oil supply hole through which the refrigerating machine oil passes with the refrigerant discharged into the sealed container is formed in the shaft center portion, and slides on the rocking bearing of the boss portion of the rocking scroll at one end portion of the main shaft portion. A crank portion that is freely fitted, and a shaft fixed to an electric motor rotor that constitutes the drive portion;
A first intermediate pressure that communicates the internal space of the boss portion with the first intermediate pressure chamber, and the pressure in the first intermediate pressure chamber is lower than the pressure in the internal space of the boss portion and higher than the suction pressure; A first pressure reducing mechanism for reducing the pressure so that
The first intermediate pressure chamber communicates with the second intermediate pressure chamber, and the pressure in the second intermediate pressure chamber is lower than the first intermediate pressure in the first intermediate pressure chamber and higher than the suction pressure. A second pressure reducing mechanism for reducing the pressure to become the second intermediate pressure,
The compliant frame receives the first intermediate pressure in the first intermediate pressure chamber and presses the orbiting scroll against the fixed scroll, and receives the second intermediate pressure in the second intermediate pressure chamber and the compressor. A scroll compressor characterized in that pressing force on a thrust receiving surface of a client frame is reduced.   2. The scroll compressor according to claim 1, further comprising a sealing material that seals a space between the internal space of the boss portion of the swing scroll and the second intermediate pressure chamber. The second intermediate pressure is determined by the pressure in the outer space of the compliant frame, the spring force of the third intermediate pressure adjusting spring of the third pressure reducing mechanism and the intermediate pressure exposure area of the third intermediate pressure adjusting valve; Is the sum of
3. The scroll compressor according to claim 1, further comprising the third pressure reducing mechanism that communicates with the suction pressure space side when the pressure in the second intermediate pressure chamber reaches the second intermediate pressure. 4.   The slider is disposed between the crank portion of the shaft and the rocking bearing of the rocking scroll, and a gap is formed between the slider and the crank portion. 4. The scroll compressor according to any one of 3. There is the gap between an end portion of the slider in the eccentric direction of the crank portion and the crank portion,
The scroll compressor according to claim 4, wherein the slider can slide in an eccentric direction of the crank portion by the gap. There is the gap between the crank portion and an end portion in a direction inclined by a certain angle from the eccentric direction of the crank portion in the slider to the counter-rotating direction,
5. The scroll compressor according to claim 4, wherein the slider is slidable in a direction inclined by a predetermined angle from the eccentric direction of the crank portion in the counter-rotating direction by an amount corresponding to the gap.

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