JP6633305B2 - Scroll compressor - Google Patents

Description

  The present invention relates to a scroll compressor, and more particularly to a scroll compressor used in a refrigeration circuit of a vehicle air conditioner.

  Patent Literature 1 discloses a shaft seal that accommodates a fixed scroll and a movable scroll in a housing, supports a rotation shaft via a bearing in the housing, and has a shaft seal mechanism fitted between the rotation shaft and the housing. As a lubricating means of the mechanism, there is disclosed a scroll compressor having a communication passage communicating between a seal chamber and a refrigerant suction chamber.

Japanese Patent No. 2868998

  When the compressor has a structure in which the suction port is provided on the outer peripheral side of the scroll unit on the outer peripheral wall of the housing, the refrigerant introduced from the suction port can be immediately sucked into the scroll unit, thereby improving the compression efficiency of the refrigerant. Can be expected. On the other hand, in the compressor having such a structure, the flow rate of the refrigerant flowing into a portion of the housing distant from the suction port is reduced, and there has been a concern about deterioration of lubrication particularly of a lip seal as a shaft seal mechanism or a sealing device.

As described in Patent Document 1, simply forming a communication path that communicates between the seal chamber and the suction chamber side of the refrigerant increases the communication path when the lip seal is separated from the suction port. Is difficult to supply.
The present invention has been made in view of such a problem, and an object of the present invention is to positively guide lubricating oil to a sealing device, thereby increasing the compression efficiency of the compressor and reducing the wear of the sealing device. The present invention is to provide a scroll compressor that can greatly reduce the pressure, and further ensure the residual interference of the sealing device with respect to the rotating shaft, and maintain the sealing performance of the compressor for a long period of time.

In order to achieve the above object, a scroll compressor of the present invention includes a scroll unit that compresses a refrigerant by orbiting a movable scroll with respect to a fixed scroll, and converts a rotational motion of a rotating shaft into a revolving orbiting motion of a movable scroll. A housing that includes a crank mechanism that transmits and transmits the scroll unit, a housing that houses the scroll unit, and has a refrigerant suction port on an outer peripheral wall located on the outer peripheral side of the scroll unit, and a sealing device that seals between the housing and the rotating shaft. A first chamber extending from an opening of the communication hole in the seal chamber to a vicinity of the seal device; a crank chamber in which the crank mechanism is positioned, a seal chamber in which the seal device is positioned, a communication hole communicating the crank chamber with the seal chamber; possess a guide groove, the crank mechanism includes a counterweight attached to the rotary shaft, the communication hole They are formed at positions that are intermittently covered with the counterweight with the swiveling of the counterweight.

Preferably, the housing further has a second guide groove in which the opening of the communication hole in the crankcase is located .

Preferably, the communication hole is inclined along the turning direction of the counterweight with respect to the radial direction of the rotating shaft.
Preferably, the counterweight has an inclined surface inclined with respect to the axis of the rotation axis.
Preferably, the counterweight has a step surface protruding in the radial direction of the rotation shaft.

  ADVANTAGE OF THE INVENTION According to the scroll compressor of this invention, the lubricating oil is actively guide | induced to a sealing device, and while increasing the compression efficiency of a compressor, the abrasion of a sealing device is reduced sharply and the sealing device with respect to a rotating shaft is further reduced. It is possible to secure the residual interference and maintain the sealing performance of the compressor for a long period of time.

It is a longitudinal section of a scroll compressor concerning a 1st embodiment of the present invention. FIG. 2 is a longitudinal sectional view of a scroll compressor in which a part of a crank chamber and a seal chamber of FIG. 1 is enlarged. FIG. 2 is a plan view of the front housing of FIG. 1 as viewed from an opening end side. FIG. 4 is a plan view showing another embodiment of FIG. 3. FIG. 4 is a plan view showing still another embodiment of FIG. 3. It is the longitudinal section of the scroll compressor which expanded a part of crankcase and seal room concerning a 2nd embodiment of the present invention. FIG. 7 is a plan view of the front housing of FIG. 6 as viewed from the opening end side. It is the top view which looked at the front housing concerning a 3rd embodiment of the present invention from the opening end side. FIG. 14 is a side view showing a state where a counterweight according to a fourth embodiment of the present invention is mounted on a rotating shaft. FIG. 10 is a side view showing another embodiment of FIG. 9. FIG. 10 is a side view showing still another form of FIG. 9.

Hereinafter, each embodiment of the present invention will be described with reference to the drawings.
<First embodiment>
FIG. 1 is a longitudinal sectional view of a scroll compressor 1 according to a first embodiment of the present invention. The compressor 1 is incorporated in, for example, a refrigeration circuit of a vehicle air conditioner mounted on a vehicle, and is used for compressing a refrigerant circulating in the refrigeration circuit.

  The compressor 1 includes a rear housing (housing) 2 and a front housing (housing) 4, and a scroll unit 6 is disposed in the rear housing 2. The scroll unit 6 includes a fixed scroll 8 fixed to the rear housing 2 and a movable scroll 10 assembled so as to mesh with the fixed scroll 8. The fixed scroll 8 includes an end plate 8a and a fixed scroll 8b formed integrally with the end plate 8a. The movable scroll 10 includes an end plate 10a and a movable scroll 10b formed integrally with the end plate 10a. The fixed scroll 8b and the movable scroll 10b are engaged with each other.

  A discharge chamber 12 is formed in the rear housing 2 between the end wall 2 a of the rear housing 2 and the fixed scroll 8. The discharge chamber 12 is provided in a compression chamber 18 formed between the fixed scroll 8 and the movable scroll 10 through a discharge valve 14 of a reed valve type in a discharge hole 14 formed in an end plate 8 a of the fixed scroll 8. Communication is possible. A discharge port 20 is formed on the outer peripheral wall 2b of the rear housing 2 at a position close to the end wall 2a, and the discharge chamber 12 communicates with the refrigerant circulation path of the refrigeration circuit via the discharge port 20.

Further, on the outer peripheral wall 2b of the rear housing 2, a refrigerant suction port 22 is provided on the outer peripheral side of the scroll unit 6, and the refrigerant introduced from the refrigerant circulation path via the suction port 22 is quickly sucked into the scroll unit 6. Is done.
On the other hand, a rotary shaft 24 is disposed in the front housing 4, and the rotary shaft 24 has a large-diameter shaft portion 24a and a small-diameter shaft portion 24b. The front housing 4 has a large-diameter inner peripheral surface 4b, a medium-diameter internal peripheral surface 4c, and a small-diameter inner diameter that are sequentially reduced from the opening end 4a located on the rear housing 2 side by gradually reducing the inner circumference. An inner peripheral surface 4d is formed.

  The large-diameter shaft portion 24a is rotatably supported on a medium-diameter inner peripheral surface 4c of the front housing 4 via a bearing 26 which is a needle bearing, and the small-diameter shaft portion 24b is front-mounted via a bearing 28 which is a ball bearing. The small diameter inner peripheral surface 4d of the housing 4 is rotatably supported. A lip seal (sealing device) 30 is arranged between the small-diameter shaft portion 24b and the small-diameter inner peripheral surface 4d of the front housing 4. The outer peripheral side of the lip seal 30 is mounted on the small-diameter inner peripheral surface 4d, and the lip portion located on the inner peripheral side contacts the rotating small-diameter shaft portion 24b to function as a sealing device, so that the inside of the front housing 4 is airtight. Partition.

  The small-diameter shaft portion 24b of the rotating shaft 24 protrudes from the front housing 4, and this protruding end is connected to a drive pulley 32 having a built-in electromagnetic clutch. The drive pulley 32 is rotatably supported by the front housing 4 via a bearing 34 that is a ball bearing. The drive pulley 32 is connected to an output pulley on the engine side of the vehicle via a belt, and is rotated by receiving the power of the engine.

  On the other hand, a crank pin 24 c projects from the large-diameter shaft portion 24 a of the rotating shaft 24 toward the orbiting scroll 10. The crank pin 24c is provided at a position eccentric from the axis of the rotating shaft 24, and is inserted and fitted into a crank pin hole 38 formed in the eccentric bush 36. The crank pin 24c supports the eccentric bush 36 by its base end 24c1. The eccentric bush 36 supports the boss 41 of the movable scroll 10 via a bearing 40 which is a needle bearing.

  A counter weight 42 is attached to the crank pin 24c so as to be sandwiched between the eccentric bush 36 and the large-diameter shaft portion 24a. The counterweight 42 is formed by stacking a plurality of large and small arc-shaped plates 42 a in the axial direction of the rotary shaft 24, cancels the centrifugal force acting on the rotary shaft 24 with the orbital rotation of the movable scroll 10, and The balance of orbital rotation is taken.

Thus, the crank mechanism 44 that converts the rotational motion of the rotary shaft 24 into the revolving orbiting motion of the orbiting scroll 10 and transmits the same is configured from the above-described crank pin 24c, the eccentric bush 36, the boss 41, and the counterweight 42. I have.
A ball-coupling type rotation preventing mechanism 46 is arranged between the end plate 10 a of the orbiting scroll 10 and the opening end 4 a of the front housing 4. The anti-rotation mechanism 46 prevents the orbiting scroll 10 from rotating without hindering the orbital movement of the orbiting scroll 10 with respect to the fixed scroll 8.

  In the compressor 1 configured as described above, when the electromagnetic clutch in the drive pulley 32 is turned on during the operation of the engine and the rotating shaft 24 rotates together with the drive pulley 32, the crankpin 24c is fitted. The eccentric bush 36 rotates. Accordingly, the orbiting scroll 10 is given a revolving motion through the boss 41 in a state where the rotation is prevented by the rotation preventing mechanism 46.

  When the orbiting scroll 10 revolves around the fixed scroll 8, the refrigerant drawn from the refrigerant circulation path via the suction port 22 is introduced into the scroll unit 6, and the fixed scroll 8 and the movable scroll 10 cooperate. Thereby, the compression chamber 18 for the refrigerant containing the lubricating oil is formed between the fixed scroll 8b and the movable scroll 10b. In the compression chamber 18, the volume of the movable scroll 10b is reduced while moving toward the center of the fixed scroll 8b due to the revolving orbiting motion of the movable scroll 10 with respect to the fixed scroll 8, so that the refrigerant is compressed. The compressed refrigerant is discharged to the discharge chamber 12 through the discharge holes 14 and is discharged from the discharge port 20 to the refrigerant circulation path.

  Here, in the front housing 4, a crank chamber 48 is defined inside the large-diameter inner peripheral surface 4b. The crank chamber 48 is a space in the front housing 4 in which the crank mechanism 44 is positioned, and allows the counter weight 42 to smoothly revolve around the rotation of the rotating shaft 24. In the crank chamber 48, a ring-shaped pedestal surface 48a substantially perpendicular to the axis of the rotating shaft 24 is formed as a step surface between the large-diameter inner peripheral surface 4b and the medium-diameter inner peripheral surface 4c of the front housing 4. The arc-shaped plate 42a of the counterweight 42 is positioned close to the pedestal surface 48a.

  On the other hand, in the front housing 4, a seal chamber 50 is defined from the inside of the middle diameter inner peripheral surface 4c to the inside of the small diameter inner peripheral surface 4d. The seal chamber 50 is a space in which the lip portion of the lip seal 30 is positioned, and is a step surface between the middle diameter inner peripheral surface 4c and the small diameter inner peripheral surface 4d of the front housing 4, and is substantially orthogonal to the axis of the rotating shaft 24. A ring-shaped pedestal surface 50a is formed, and the bearing 26 mounted on the medium-diameter inner peripheral surface 4c is positioned close to the pedestal surface 50a.

  FIG. 2 is an enlarged sectional view of a part of the crank chamber 48 and the seal chamber 50, and FIG. 3 is a plan view of the front housing 4 as viewed from its open end 4a. As shown in FIGS. 2 and 3, in the present embodiment, two communication holes 52 communicating the crank chamber 48 and the seal chamber 50 are provided in the front housing 4 at symmetrical positions sandwiching one diagonal rotation shaft 24. Penetrated. Each communication hole 52 is inclined with respect to the axis of the rotating shaft 24, extends linearly along the radial direction of the rotating shaft 24, opens in the pedestal surface 48 a in the crank chamber 48, and rotates with the rotation of the counterweight 42. It is formed at a position intermittently covered by the arc-shaped plate 42a.

  On the other hand, in the seal chamber 50, each communication hole 52 is opened near the pedestal surface 50a of the middle diameter inner peripheral surface 4c. The openings of the communication holes 52 on the side of the crank chamber 48 and the side of the seal chamber 50 are substantially positioned on the diameter line of the rotating shaft 24. A guide groove (first guide groove) 54 extends from the communication hole 52 opened in the medium-diameter inner peripheral surface 4 c to the vicinity of the lip portion of the lip seal 30 on the pedestal surface 50 a which is the inner wall of the seal chamber 50. Is recessed. The guide groove 54 is formed with a bottom that is inclined in an arc shape with respect to the axis of the rotating shaft 24, and extends from the communication hole 52 opened in the middle diameter inner peripheral surface 4 c to the vicinity of the lip portion of the lip seal 30. It extends linearly along the radial direction of the rotating shaft 24.

  Here, when the refrigerant flows from the suction port 22 toward the compression chamber 18 with the orbital movement of the orbiting scroll 10, the refrigerant containing the lubricating oil also flows on the back surface 10c side of the end plate 10a of the orbiting scroll 10. When the refrigerant flows into the crank chamber 48, the orbiting scroll 10 is suitably pressed and urged toward the fixed scroll 8. The lubricating oil flowing into the crank chamber 48 together with the refrigerant lubricates the anti-rotation mechanism 46, the bearing 40, the bearing 26, and the lip seal 30.

  More specifically, as shown by solid arrows in FIGS. 2 and 3, the refrigerant flowing into the crank chamber 48 includes an arc-shaped plate 42 a of the counterweight 42 when the counterweight 42 swirls in a two-dot chain line arrow direction, It is temporarily compressed in a minute gap formed between the arc-shaped plate 42a and the adjacent pedestal surface 48a. The refrigerant compressed in the crank chamber 48 is extruded from the communication hole 52 to a lower pressure seal chamber 50 by a differential pressure.

  The refrigerant that has flowed from the crank chamber 48 into the seal chamber 50 through the communication hole 52 in this way flows through the guide groove 54 and is guided to the lip seal 30, and at this time, the lip seal 30 is lubricated by the coolant. Is suitably lubricated. On the other hand, as indicated by broken lines in FIGS. 2 and 3, the refrigerant flowing into the seal chamber 50 passes through the bearing 26 and returns to the crank chamber 48. At this time, the bearing 26 is favorably moved by the lubricating oil contained in the refrigerant. Lubricated. Thus, a lubricating oil circulation path is formed between the crank chamber 48 and the seal chamber 50.

  As described above, according to the present embodiment, when the suction port 22 is provided on the outer peripheral wall 2b of the rear housing 2 on the outer peripheral side of the scroll unit 6 as in the compressor 1, the air is introduced from the inlet port 22. Since the drawn refrigerant can be immediately sucked into the scroll unit 6, an improvement in refrigerant compression efficiency can be expected. On the other hand, in the compressor 1 having such a structure, the flow rate of the refrigerant flowing into a portion of the front housing 4 distant from the suction port 22 is reduced, and particularly, deterioration of lubrication of the lip seal 30 has conventionally been concerned.

  Even in such a case, since the communication hole 52 and the guide groove 54 are formed in the front housing 4 and the lubricating oil circulation path is formed between the crank chamber 48 and the seal chamber 50, the lubricating oil is lip sealed. 30 can be positively guided. Therefore, the wear of the lip seal 30 can be significantly reduced while increasing the compression efficiency of the compressor 1, and the residual interference of the lip seal 30 with respect to the small-diameter shaft portion 24b can be secured. The sealing performance of the compressor 1 can be maintained. The numbers of the communication holes 52 and the guide grooves 54 are not particularly limited. For example, as illustrated in FIG. 4, two sets of the communication holes 52 and the guide grooves 54 are formed at symmetrical positions sandwiching the two diagonal rotation shafts 24. Alternatively, as shown in FIG. 5, only one set of the communication hole 52 and the guide groove 54 may be formed.

<Second embodiment>
FIG. 6 is an enlarged sectional view of a part of a crank chamber 48 and a seal chamber 50 according to a second embodiment of the present invention, and FIG. 7 is a plan view of the front housing 4 of FIG. It is. In addition, about the structure similar to 1st Embodiment, the same name and the same code | symbol are attached in a specification or drawing, and description may be abbreviate | omitted.

  As shown in FIGS. 6 and 7, two guide grooves (the second guide grooves) are provided on the pedestal surface 48 a of the front housing 4 of the present embodiment at positions sandwiching the rotary shaft 24 on the same diagonal line as the guide grooves 54 of the pedestal surface 50 a. Guide groove) 56 is recessed. Each guide groove 56 extends linearly along the radial direction of the rotating shaft 24 from the vicinity of the large-diameter inner peripheral surface 4b to the vicinity of the middle-diameter inner peripheral surface 4c, and the communication hole 52 is formed at the bottom of the guide groove 56. ing.

  As described above, in the present embodiment, since the guide groove 56 similar to the guide groove 54 of the pedestal surface 50a is formed at the opening position of the communication hole 52 on the pedestal surface 48a, as shown by solid arrows in FIGS. In addition, the lubricating oil attached to the pedestal surface 48a can be efficiently guided from the guide groove 56 to the communication hole 52, and the lubricating oil can be more positively guided to the lip seal 30. Accordingly, while increasing the compression efficiency of the compressor 1, the wear of the lip seal 30 is further significantly reduced, the residual interference of the lip seal 30 is secured, and the sealing performance of the compressor 1 is maintained for a long period of time. Can be.

<Third embodiment>
FIG. 8 is a plan view of the front housing 4 according to the third embodiment of the present invention as viewed from the opening end 4a side. Note that this embodiment will be described as another embodiment of FIG. 5 shown in the first embodiment, and the same configurations as those in the first embodiment will be described with the same names and the same reference numerals in the specification or the drawings. May be omitted.

  As shown in FIG. 8, one communication hole 58 that connects the crank chamber 48 and the seal chamber 50 to each other is formed in the front housing 4. The communication hole 58 extends linearly inclining with respect to both the axis and the radial direction of the rotating shaft 24 as shown by a broken line. The inclination of the rotating shaft 24 with respect to the radial direction is a direction along the turning direction of the counterweight 42. That is, the openings of the communication hole 58 on the side of the crank chamber 48 and the side of the seal chamber 50 are positioned obliquely with the diameter line of the rotating shaft 24.

  As described above, in the present embodiment, since the communication hole 58 having a shape different from the communication hole 52 of the first and second embodiments is formed, the communication hole 58 flows into the communication hole 58 as indicated by a solid arrow in FIG. The lubricating oil can be guided to the lip seal 30 more efficiently and quickly by utilizing the force in the turning direction of the counterweight 42 acting on the refrigerant and the lubricating oil. Accordingly, while increasing the compression efficiency of the compressor 1, the wear of the lip seal 30 is further significantly reduced, the residual interference of the lip seal 30 is secured, and the sealing performance of the compressor 1 is maintained for a long period of time. Can be.

<Fourth embodiment>
FIG. 9 is a side view showing a state where the counterweight 60 according to the fourth embodiment of the present invention is mounted on the rotating shaft 24. In addition, about the structure similar to any of 1st-3rd embodiment, the same name and the same code | symbol are attached in a specification or drawing, and description may be abbreviate | omitted.

  As shown in FIG. 9, in the counterweight 60 of the present embodiment, the radial end face 60 a 1 of each arc-shaped plate 60 a is inclined with respect to the axis of the rotating shaft 24, and a flat inclined surface 62 is formed. The inclined surface 62 is inclined in a direction approaching the axis from the crank pin 24c toward the large-diameter shaft portion 24a, and adheres to the radial end surface 60a1 of each arc-shaped plate 60a as the counterweight 60 turns. The lubricating oil is guided toward the communication hole 52 or the communication hole 58 as indicated by a solid line arrow.

  As described above, in the present embodiment, since the counterweight 60 has the inclined surface 62, the lubricating oil attached to the radial end surface 60a1 of each arc-shaped plate 60a can be efficiently guided to the communication hole 52 or the communication hole 58. Therefore, the lubricating oil can be more positively guided to the lip seal 30. Accordingly, while increasing the compression efficiency of the compressor 1, the wear of the lip seal 30 is further significantly reduced, the residual interference of the lip seal 30 is secured, and the sealing performance of the compressor 1 is maintained for a long period of time. Can be.

  The present invention is not limited to the above-described embodiment. For example, as shown in FIG. 10, an inclined surface 64 may be formed by inclining only the radial end surface 60a1 of one arc-shaped plate 60a closest to the large-diameter shaft portion 24a. Further, as shown in FIG. 11, one of the arc-shaped plates 60a may be projected in the radial direction of the rotating shaft 24 to form a step surface 66 from the radial end face 60a1 of each arc-shaped plate 60a. In these cases, as shown by the solid arrows in FIGS. 10 and 11, the lubricating oil attached to the counterweight 60 can be efficiently flowed or dripped into the communication hole 52 or the communication hole 58 to be guided.

The present invention is not limited to the above embodiments, and various modifications are possible.
For example, in each of the above embodiments, the engine-driven scroll compressor 1 incorporated in the vehicle air conditioner has been described. However, the present invention is applicable to an integrated electric motor-driven scroll compressor and scroll compressors in various fields using various working fluids.

1 scroll compressor 2 rear housing (housing)
2b Outer wall 4 Front housing (housing)
Reference Signs List 6 scroll unit 8 fixed scroll 10 movable scroll 22 suction port 24 rotation axis 30 lip seal (sealing device)
42, 60 Counterweight 44 Crank mechanism 48 Crank chamber 50 Seal chamber 52 Communication hole 54 Guide groove (first guide groove)
56 Guide groove (second guide groove)
62, 64 Inclined surface 66 Step surface

Claims (5)

A scroll unit that compresses refrigerant by orbiting of a movable scroll with respect to a fixed scroll,
A crank mechanism that converts the rotational motion of the rotating shaft into a revolving orbiting motion of the orbiting scroll and transmits the same;
A housing in which the scroll unit is accommodated, and a housing having a refrigerant suction port on an outer peripheral wall located on an outer peripheral side of the scroll unit; and a sealing device for sealing between the housing and the rotating shaft;
With
The housing is
A crank chamber in which the crank mechanism is located;
A seal chamber in which the sealing device is located, and a communication hole communicating the crank chamber and the seal chamber;
Possess a first guide groove extending from the opening of the communication hole in the seal chamber in the vicinity of the sealing device,
The crank mechanism includes a counterweight attached to the rotating shaft,
The scroll compressor, wherein the communication hole is formed at a position where the communication hole is intermittently covered with the counterweight as the counterweight rotates .   The scroll compressor according to claim 1, wherein the housing further has a second guide groove in which an opening of the communication hole in the crank chamber is located. The communication hole, the relative radial direction of the rotating shaft is inclined along the turning direction of the counterweight, the scroll compressor according to claim 1 or 2. The scroll compressor according to any one of claims 1 to 3 , wherein the counterweight has an inclined surface inclined with respect to an axis of the rotation shaft. The scroll compressor according to any one of claims 1 to 4 , wherein the counterweight has a step surface protruding in a radial direction of the rotation shaft.

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