JP6618317B2 - Scroll type fluid machinery - Google Patents

Description

  The present invention relates to a scroll type fluid machine.

  A scroll type fluid machine is used as a compressor included in an air conditioner of a vehicle, for example. Such a scroll type fluid machine meshes a fixed scroll and a movable scroll in which a spiral body protrudes from a disk-shaped end plate, and causes the movable scroll to swing with respect to the fixed scroll. Thereby, the volume of the pressure chamber of the working fluid formed between both spiral bodies decreases as it goes toward the center, and the working fluid is compressed.

  In such a scroll type fluid machine, a tip seal is provided on the tip surface of the scroll of each scroll. The tip seal is in sliding contact with the opposing end plate to ensure the airtightness of the pressure chamber. The tip seal also has a lubrication function to prevent the scrolls made of metal from being touched and worn.

  The tip seal having such a function is ideally provided over the entire area of the spiral body, but in that case, there may be a range extending to the outside of the orbit of the movable scroll. The tip seal that extends to the outside of the orbit of the orbiting scroll does not come into contact with the opposing end plate, and thus may be detached from the tip surface of the spiral body.

  On the other hand, Patent Document 1 discloses that the tip seal on the fixed scroll side is attached so that the outer peripheral end portion thereof is positioned near the outer side of the turning locus formed by the outer peripheral end of the end plate of the movable scroll. .

JP 2001-221176 A

  In Patent Document 1, a range outside the turning trajectory of the movable scroll at the outer peripheral end portion of the tip seal on the fixed scroll side is defined. However, when the tip seal is provided over the entire area of the spiral body, Even within the turning trajectory, there is a range on the outer peripheral side of the tip seal that repeats contact and non-contact intermittently with the facing end plate in the process of turning the movable scroll. In such a range, every time the end plate is brought into contact with the end plate, the edge portion of the end plate collides and receives a large force in the shearing direction. There is a problem of doing.

  In general, the movable scroll has a boss at the center of the end plate supported via a bearing. There is also a problem that distortion occurs and the tip seal on the outer peripheral side of the fixed scroll is more easily worn.

  Such a problem can be dealt with by always limiting the area where the tip seal is provided to the area where it is in contact with the end plate, but doing so will increase the leakage of the working fluid and reduce the performance of the scroll type fluid machine. Will be invited. Alternatively, the range of contact between the tip seal and the end plate can be expanded by enlarging the diameter of the end plate of the movable scroll, but this increases the weight, which may reduce the performance.

  The present invention has been made in view of such problems, and the purpose of the present invention is to extend the tip seal to the entire area of the spiral body to improve the airtightness and improve the performance while improving the wear on the outer periphery of the tip seal. It is an object of the present invention to provide a scroll type fluid machine that can suppress the above.

In order to achieve the above object, a scroll type fluid machine of the present invention includes a fixed scroll and a movable scroll each having an end plate and a spiral body integral with the end plate, and the spiral body between the fixed and movable scrolls. And a scroll type fluid machine that divides a pressure chamber of a working fluid formed between the spiral bodies by sliding the end plates in contact with each other via a tip seal provided on a tip surface of the spiral body, and at least one of them The tip seal provided on the scroll is fitted and attached to a seal groove formed on the front end surface, and there is a range that intermittently deviates from the range of the opposed end plates as the movable scroll turns. The axial thickness protruding from the tip surface of the spiral body is formed as a thin part thinner than the other part, and the thin part is provided on the fixed scroll. Formed on the outer peripheral edge side of the Pushiru contactless der has the end plate and the gap facing is, the axial thickness of the thin portion is constant.

Preferably, the axial thickness of the front Symbol thin portion is inclined so as to become thinner toward the outer peripheral end. Alternatively, the tip seal is provided by being fitted into a seal groove formed on the front end surface of the spiral body, and the thin portion is formed so that the depth of the seal groove is deeper than other portions. It may be formed.

  Further, the chip seal may be provided by being fitted into a seal groove formed on the tip surface of the spiral body, and the seal groove may have a trapezoidal cross section with an opening side narrowed.

  According to the scroll type fluid machine of the present invention, it is possible to suppress wear on the outer periphery of the chip seal while extending the chip seal to the entire area of the spiral body to improve the airtightness and improve the performance.

It is a schematic structure figure of a scroll compressor concerning one embodiment of the present invention. (A) The top view of a fixed scroll when a movable end plate is spaced apart in the whole thin part, and (b) The top view of a fixed scroll when a movable end plate is approaching in the whole thin part. FIG. 2A is a cross-sectional view taken along line A1-A1, and FIG. 2B is a cross-sectional view taken along line A2-A2 in FIG. 2A is a cross-sectional view taken along line B1-B1 in FIG. 2A, and FIG. 2B is a cross-sectional view taken along line B2-B2 in FIG. It is sectional drawing which shows the 1st modification of the thin part in this embodiment. It is sectional drawing which shows the 2nd modification of the thin part in this embodiment. It is sectional drawing which shows the modification of the seal groove in this embodiment.

  FIG. 1 shows a scroll compressor (scroll type fluid machine) 1 according to the present invention. This compressor 1 is incorporated in a refrigeration circuit for air-conditioning a vehicle and compresses refrigerant (working fluid) circulating in the refrigeration circuit. used.

  The compressor 1 includes a rear housing 2 and a front housing 4, and a scroll unit 6 is accommodated 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. A series of processes from suction to compression through discharge are continuously performed.

  More specifically, a discharge chamber 12 is formed in the rear housing 2 between the end plate 2 a and the fixed scroll 8 of the scroll unit 6, and the discharge chamber 12 is formed in the fixed end plate 8 a of the fixed scroll 8. While being connectable to the discharge hole 14 via a reed valve type discharge valve 16, it is connected to the refrigerant circulation path of the refrigeration circuit via a discharge port (not shown) formed in the rear housing 2.

  The rear housing 2 is also provided with a refrigerant suction port (not shown). The suction port introduces the refrigerant into the rear housing 2 from the refrigerant circulation path, and the introduced refrigerant enters the scroll unit 6. Inhaled.

  On the other hand, a drive shaft 18 is disposed in the front housing 4, and the drive shaft 18 has a large-diameter end portion 20 and a small-diameter shaft portion 22. The large diameter end portion 20 is rotatably supported by the front housing 4 via a needle bearing 24, and the small diameter shaft portion 22 is rotatably supported by the front housing 4 via a ball bearing 26. Further, a lip seal 28 is disposed between the small diameter shaft portion 22 and the front housing 4, and the lip seal 28 partitions the inside of the front housing 4 in an airtight manner.

  A small-diameter shaft portion 22 of the drive shaft 18 protrudes from the front housing 4, and the protruding end is connected to a drive pulley 30 incorporating an electromagnetic clutch. The drive pulley 30 is rotatably supported by the front housing 4 via a bearing 32. ing. The driving pulley 30 is connected to an output pulley on the engine side of the vehicle via a belt, and is rotated by receiving power from the engine. Therefore, during driving of the engine, if the electromagnetic clutch in the drive pulley 30 is on, the drive shaft 18 rotates with the drive pulley 30.

  On the other hand, a crank pin 34 projects from the large-diameter end 20 of the drive shaft 18 toward the movable scroll 10, and the crank pin 34 supports the boss 40 of the movable scroll 10 via an eccentric bush 36 and a needle bearing 38. ing. Therefore, when the drive shaft 18 is rotated, the movable scroll 10 performs a turning motion via the crank pin 34 and the eccentric bush 36.

  Further, a rotation prevention coupling is disposed between the front housing 4 and the movable end plate 10 a of the movable scroll 10. In the case of this embodiment, the rotation prevention coupling comprises a so-called EM coupling 42, and the EM coupling 42 is configured by sandwiching a ball 48 between the annular race grooves of both the movable plate 44 and the fixed plate 46 each having a ring shape. ing.

  The fixed scroll 8 has a fixed spiral body 50 formed integrally with the fixed end plate 8a, and the movable scroll 10 also has a movable spiral body 52 formed integrally with the movable end plate 10a. Most of the inner and outer surfaces of the fixed and movable spiral bodies 50 and 52 are formed of involute curves, and are formed of, for example, an aluminum alloy.

  The discharge hole 14 described above is positioned in the vicinity of the central end 50b of the fixed spiral body 50, and a certain clearance is secured between the inner surface of the central end 50b.

  A fixed tip seal 54 is provided on the distal end surface 50 a of the fixed spiral body 50, and a movable tip seal 56 is provided on the distal end surface 52 a of the movable spiral body 52. Specifically, the fixed and movable tip seals 54 and 56 are attached so as to fit into seal grooves 60 and 62 formed in the front end surfaces 50a and 52a of the fixed and movable spiral bodies 50 and 52, respectively. The fixed and movable tip seals 54 and 56 have an elastic modulus of about 1/30 or less of the fixed and movable spiral bodies 50 and 52 formed from the above-described aluminum alloy, for example, engineering plastic such as polyphenylene sulfide (PPS). Molded from.

  The fixed spiral body 50 and the movable end plate 10 a are slidably contacted with each other via a fixed tip seal 54, while the movable spiral body 52 and the fixed end plate 8 a are slidably contacted with each other via a movable tip seal 56. By these sliding contacts between the fixed and movable scrolls 8 and 10, a refrigerant compression chamber (pressure chamber) 58 is defined between the fixed and movable spiral bodies 50 and 52, and the above-described series of processes continues. Executed.

  Here, the fixed chip seal 54 will be described in detail. 2A and 2B are plan views of the fixed scroll, and FIGS. 3A and 3B and FIGS. 4A and 4B are cross-sectional views showing the relationship between the fixed chip seal and the movable end plate, respectively. Will be described below with reference to these drawings.

  First, as shown in FIGS. 2A and 2B, the fixed chip seal 54 extends from the central end 50b of the fixed spiral body 50 to the outer peripheral end 50c. Here, in FIGS. 2A and 2B, the range of the movable end plate 10a is indicated by a dotted line, and in FIG. 2A, the fixed tip seal 54 has the smallest range that covers the movable end plate 10a. FIG. 2B shows a state in which the fixed chip seal 54 has the largest range with the movable end plate 10a.

  In the state shown in FIG. 2A, the fixed chip seal 54 is formed as a thin portion 54b in a range not covered with the movable end plate 10a with respect to the main portion 54a that is covered with the movable end plate 10a. Yes.

  As shown in FIGS. 3A and 3B, the thin-walled portion 54b has a thickness in the axial direction that protrudes from the distal end surface 50a of the fixed spiral body 50 as compared with the main portion 54a. Thinly formed. That is, the fixed chip seal 54 has a small axial thickness in a stepped manner within a predetermined range on the outer peripheral side. The axial thickness of the thin portion 54b is, for example, a thickness at which the outer peripheral end does not come into contact with the movable end plate 10a even when the movable end plate 10a is distorted to the maximum extent, as indicated by a dotted line in FIG. Is set.

  As described above, the fixed chip seal 54 is formed as a thin portion 54b whose axial thickness is thinner than other portions in the range where the movable scroll 10 is intermittently removed from the opposing movable end plate 10a as the movable scroll 10 turns. ing. Thus, as is apparent from FIGS. 3B and 4B, even when the movable end plate 10a is covered by the thin portion 54b, the thin portion 54b has a certain gap from the movable end plate 10a. There is no contact. Therefore, even if the movable end plate 10a intermittently passes through the range of the thin portion 54b by turning the movable scroll 10, the edge portion of the movable end plate 10a does not collide with the fixed chip seal 54. In particular, by setting the thickness of the thin portion 54b in consideration of the distortion of the movable end plate 10a, the fixed chip seal 54 is not reliably in contact with the movable end plate 10a.

  On the other hand, the fixed tip seal 54 extends to the outer peripheral end 50c of the fixed spiral body 50, and the thin portion 54b is formed on the compression upstream side even if the thin portion 54b is not in contact with the movable end plate 10a. Therefore, the compression chamber 58 has a low pressure and the lubricating oil in the scroll unit 6 fills the gap between the thin wall portion 54b and the movable end plate 10a. Can be suppressed. As a result, the compression efficiency of the compressor 1 is increased, and the performance can be improved.

  As described above, the scroll type fluid machine according to the present embodiment suppresses the wear on the outer periphery side of the fixed tip seal 54 while improving the performance by extending the fixed tip seal 54 to the entire area of the fixed spiral body 50 to improve the airtightness. Can do.

  This is the end of the description of the embodiment of the present invention. However, the present invention is not limited to this embodiment, and various modifications can be made without departing from the spirit of the present invention.

  In the above embodiment, the thickness of the thin portion 54b in the axial direction is constant, but the thickness of the thin portion in the axial direction may be any thickness that does not contact the opposing end plates. Thus, for example, FIG. 5 shows a first modification of the present embodiment.

  FIG. 5 is a cross-sectional view corresponding to FIG. 3 (b), and the axial thickness of the thin portion 54 b ′ of the fixed chip seal 54 ′ is inclined so as to become thinner toward the outer peripheral end. Also in the first modified example, the same effect as in the above embodiment can be obtained.

  Further, since the thin portion of the tip seal only needs to have a smaller axial thickness protruding from the tip surface of the spiral body than the other portions, the fixed tip seal 54, as in the above embodiment and the first modification, Instead of reducing the thickness of 54 'itself, the thickness of the fixed tip seal 54' 'is constant throughout the entire area as in the second modification shown in FIG. Even if the thin portion 54b '' is formed by making the depth of the portion deeper than that of the other portions, the same effect can be obtained.

  Further, the seal grooves 60, 60 ', 60' 'of the above-described embodiment and each modification have a rectangular cross section, but the cross sectional shape of the seal groove is not limited to this, for example, the seal groove shown in FIG. As in the modification of the groove, the sealing groove 60 ′ ″ may be a so-called dovetail having a trapezoidal cross section with a narrow opening side. Thereby, it is possible to make it difficult for the fixed chip seal 54 ′ ″ to come out of the seal groove 60 ″ ″ even in the thin portion 54b ′ ″ that does not contact the opposing end plate.

  Further, in the above-described embodiment and each modified example, since the movable scroll 10 turns within the range of the fixed end plate 8a, only the fixed chip seals 54, 54 ′, 54 ″, 54 ′ ″ of the fixed scroll 8 are used. In the case of a scroll type fluid machine in which the thin scroll portions 54b, 54b ′, 54b ″, 54b ′ ″ are formed but the movable scroll turns outside the range of the fixed end plate, the movable tip of the movable scroll is used. Similarly, a thin portion may be formed on the seal. In this case, in the movable tip seal, a range that is intermittently removed from the range of the opposed fixed end plates as the movable scroll turns is defined as a thin portion. Since the fixed end plate also has distortion due to the high-pressure discharge chamber on the back side on the center side, the thin portion of the movable tip seal also sets the distortion of the fixed end plate to an allowable axial thickness. Is preferred.

1 Compressor (scroll type fluid machine)
6 scroll unit 8 fixed scroll 8a fixed end plate 10 movable scroll 10a movable end plate 50 fixed spiral body 50a distal end surface 50b central end portion 50c outer peripheral end portion 52 movable spiral body 52a distal end surface 54 fixed tip seal 54a main portion 54b thin wall portion 56 Movable tip seal 58 Compression chamber (pressure chamber)
60, 62 Seal groove

Claims (4)

A tip seal provided with a fixed scroll and a movable scroll each having an end plate and a spiral body integral with the end plate, and the spiral body and the end plate provided on the front end surface of the spiral body between the fixed and movable scrolls A scroll type fluid machine that partitions a pressure chamber of a working fluid formed between the spiral bodies by sliding contact with each other,
A tip seal provided on at least one of the scrolls is fitted and attached to a seal groove formed on the tip surface, and intermittently disengages from the range of the opposed end plates as the movable scroll turns. The range is formed as a thin portion where the axial thickness protruding from the tip surface of the spiral body is thinner than the other portions,
The thin portion, the formed on the outer peripheral end of the tip seal provided in the fixed scroll, Ri contactless der has the end plate and the gap facing,
A scroll type fluid machine, wherein the thin portion has a constant axial thickness .   The scroll type fluid machine according to claim 1, wherein the thickness of the thin wall portion is inclined so as to become thinner toward the outer peripheral end. The tip seal is provided by being fitted in a seal groove formed on the tip surface of the spiral body,
The scroll type fluid machine according to claim 1, wherein the thin portion is formed by forming the seal groove deeper than other portions. The tip seal is provided by being fitted in a seal groove formed on the tip surface of the spiral body,
The scroll type fluid machine according to any one of claims 1 to 3 , wherein the seal groove has a trapezoidal cross-sectional shape with a narrow opening side.

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