JP3408808B2 - Scroll compressor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressor for circulating a refrigerant provided in an air conditioner for a vehicle and the like, and is particularly suitable for use in a scroll type compressor.

[0002]

2. Description of the Related Art Generally, in a vehicle air conditioner, the lubricating oil discharged from the compressor together with the refrigerant deteriorates heat transfer in the heat exchanger and reduces the efficiency of the refrigeration cycle. It is necessary to prevent discharge to anything other than the compressor. Therefore, a structure is adopted in which an oil separation mechanism for separating the lubricating oil and the refrigerant is installed on the discharge side of the compressor.

As such a scroll type compressor, for example, there is one disclosed in Japanese Patent Application Laid-Open No. 11-82352. This scroll type compressor has a structure schematically shown in FIG. 4, and a rear cover 4 is attached to the outer surface of a fixed scroll 1 which cooperates with the orbiting scroll 2 to form a scroll compression portion. The rear cover 4 constitutes a discharge cavity 6 together with the fixed scroll 1, an oil separation chamber 7 is formed on the downstream side of the discharge cavity 6, and an oil separator 8 is provided on the upper side. Further, the fixed scroll and the rear cover 4 form an oil sump chamber 5 that communicates with the oil discharge port of the oil separator 8. And
High-pressure refrigerant gas is supplied from the fixed scroll 1 to the discharge cavity 6 through the discharge hole by the action of the scroll compressor, and the gas reaches the oil separator 8 in the oil separation chamber 7,
In the process of passing through the oil separator 8, it is separated into gas and oil,
The separated oil will be stored in the lower oil storage chamber 5.

[0004]

As described above, the conventional scroll type compressor utilizes the space on the discharge side to partition the discharge cavity 6 between the fixed scroll 1 and the rear housing 3 and the oil sump 5 chamber. Are formed. Here, if the volume of the oil sump chamber 5 is small, there is a problem that the oil is not sufficiently stored and the function of the oil separator deteriorates. Therefore, it is necessary to increase the volume of the oil sump chamber 5. As one means for this, it is conceivable to enlarge the oil sump chamber 5 in the axial direction or the radial direction of the outer shape of the compressor. However, doing so causes a problem in downsizing.

The present invention has been made in view of the above problems of the prior art.
An object of the present invention is to provide a scroll type compressor which has a large function as an oil separator while increasing the number of oil reservoirs without increasing the outer diameter, thereby achieving downsizing.

[0006]

In order to solve the above problems, the present invention employs the following means. That is, in the scroll compressor according to claim 1, a fixed scroll that constitutes a scroll compression portion in cooperation with an orbiting scroll is fixed to a housing, and a discharge port communicating with a discharge port is provided on an outer surface of a fixed side plate of the fixed scroll. A scroll-type compressor that forms a cavity, arranges an oil separation chamber in the downstream thereof, and defines an oil sump chamber that communicates with the oil separation chamber on the outer surface of the fixed side plate, wherein the oil sump chamber is one of the housings. Part of the fixed side plate is defined by a contact wall that abuts a rear housing that forms the discharge cavity in the upper part, and the fixed side plate is provided with a recess, and the recess is formed in the fixed side plate. the fixed side plate in the central portion around the discharge port provided through the, characterized in that provided outside than three times the radius of said discharge exit port.

Since the pressure of the carrier fluid is the highest in the center of the fixed scroll, it is necessary to have a higher strength than the peripheral portion. However, if a concave portion is formed in the fixed side plate, a decrease in strength cannot be avoided. Therefore, when the concave portion of the fixed side plate is provided outside three times the radius of the discharge port to form the oil sump chamber, it is possible to secure the strength required for the fixed side plate and thin the fixed side plate where the strength is unnecessary. Thus, the volume of the oil sump chamber can be increased, and as a result, the function as the oil separator is improved.

A scroll type compressor according to a second aspect is the scroll type compressor according to the first aspect, wherein the fixed side plate thickness of the portion corresponding to the recess is thinner than the fixed side plate thickness of the portion forming the discharge cavity. And the volume of the oil sump chamber is increased.

According to the present invention, since the oil reservoir can be increased by forming a recess in a part of the fixed side plate so as to have a thin wall, the scroll compressor does not need to have a large outer shape and the oil reservoir can be formed in a larger size. The volume can be expanded, and as a result, the function as an oil separator is improved.

A scroll type compressor according to a third aspect is the scroll type compressor according to the first or second aspect, wherein:
The fixed scroll is formed by casting.

Since the fixed scroll is formed by casting, even if a thin portion is partially formed by providing the fixed scroll with a concave portion, sufficient strength can be obtained regardless of the thin portion.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIG.
It will be described with reference to FIG. 1 and 2 show a scroll compressor according to an embodiment of the present invention. The scroll type compressor shown in FIGS. 1 and 2 is applied to a horizontal type, and has a cylindrical housing 1
1, a scroll compression unit 12 installed in the housing 11, a rotary shaft 14 rotatably supported by a frame 13 fixed in the housing 11, and one end of which is connected to the scroll compression unit 12, And a pulley 15 connected to the other end of the rotary shaft 14.

The housing 11 is closed by a frame 13 and a rear housing 16 which will be described later and is attached to the fixed scroll 9 of the scroll compression section 12. Further, inside the housing 11, there is provided a suction cavity 17 which communicates with a refrigerant gas suction port 17 a, and the suction cavity 17 is formed by the scroll compression portion 12 and the frame 13.

The scroll compression unit 12 includes a housing 11
And a fixed scroll 19 fixed to the frame 13 and the eccentric pin 14 formed at one end of the rotary shaft 14 while being supported by the frame 13 and the fixed scroll 19 so as to be able to revolve.
It has an orbiting scroll 20 that fits a and revolves revolvingly with the rotation of the rotating shaft 14, and a rotation blocking portion 21 that allows the revolving orbiting motion of the orbiting scroll 20 while preventing its rotation.

The fixed scroll 19 has a fixed side plate 19a.
And a fixed-side spiral body 19b, which is formed on the inner surface of the fixed-side spiral body 19b so as to extend in the axial direction, and the tip seal 22 is fitted to the tip end surface of the fixed-side spiral body 19b. Further, the fixed side plate 19a is formed with a discharge port 23 penetrating in the central portion thereof along the axial direction, and a discharge valve 24 for opening and closing the discharge port 23 is attached to the outer surface portion thereof.

A rear housing 16 is attached to the outside of the fixed scroll 19, and a discharge cavity 18 is formed by the rear housing 16 and the fixed scroll 19. Further, a rear cover 38 is attached to the outer sides of the fixed scroll 19 and the rear housing 16, and an oil separator 40 is installed in a separation chamber 39 formed by the rear cover 38 and the rear housing 16.

On the other hand, the orbiting scroll 20 includes the fixed side plate 1.
9a, a swirl side plate 20a, and a fixed side spiral body 1 formed to extend along the axial direction on the inner surface of the swivel side plate 20a.
9b, and a spiral side spiral body 20b that meshes with the spiral shape, and a tip seal 27 is fitted to the tip end surface of the spiral side spiral body 20b.

A cylindrical boss 28 is formed on the outer surface of the turning side plate 20a along the axial direction, and a bush 29 is rotatably fitted inside the boss 28 via a turning bearing 30. There is. A through hole is formed inside the bush 29 at a position eccentric from the axis, and an eccentric pin 14a of the rotary shaft 14 described later is fitted into this through hole. The fixed scroll 19 and the orbiting scroll 20 are
The fixed side spiral body 1 is eccentric to each other by a predetermined distance.
9b and the swirl side spiral body 20b are engaged with each other with a phase difference of 180 degrees so that the side surfaces of the swirl side spiral body 20b are in line contact with each other at a plurality of points, and in that state, both tip seals 27 have the swivel side plate 20a.
And the inner surface of the fixed side plate 19a, and the fixed side spiral body 19
The compression chamber P forming a hermetically sealed space is formed at a plurality of positions having a point-symmetrical positional relationship with respect to b and the center of the swirling body 20b.

The rotary shaft 14 is rotatably supported by a bearing 31 mounted on the inner peripheral portion of the frame 13. One end of the rotary shaft 14 is eccentrically provided with an eccentric pin 14a so as to project in the axial direction.
It is fitted with 9.

The pulley 15 is connected to the other end of the rotary shaft 14 via a magnet clutch 32. The magnet clutch 32 is for transmitting and disconnecting a driving force between an engine and a compressor of a vehicle (not shown).

In this compressor, when the rotating shaft 14 rotates via the pulley 15 by the driving force of the engine, the rotation is transmitted to the orbiting scroll 20 via the eccentric pin 14a, the bush 29, the orbiting bearing 31 and the boss 28, and At this time, the orbiting scroll 20 revolves around the fixed scroll 19 while being prevented from rotating by the rotation preventing portion 21.

In this case, the low-temperature low-pressure refrigerant gas is sucked through the suction port 17a as the orbiting scroll 20 revolves, and the sucked refrigerant gas is fixed.
By being compressed in the compression chamber P between the rotary shaft 9 and the orbiting scroll 20, the temperature and pressure become high, the discharge port 23 passes through the discharge valve 24 to reach the discharge cavity 18, and the discharge port 18a sends the discharge cavity 18 to the separation chamber 39. . And
The refrigerant gas flowing into the separation chamber 39 is separated into oil and gas in the process of passing through the oil separator 40, and the gas is discharged in a desired direction from above, while the oil drips inside the separation chamber 39 and the rear cover 38 Also, the oil is stored in the oil sump chamber 41 through the narrow path between the lower part of the rear housing 16.

The oil sump chamber 41 has a scroll compression section 12
It is provided at the bottom of. That is, the oil sump chamber 41 includes the fixed scroll 19, the rear housing 16, and the rear cover 3.
It is defined by 8.

In the present embodiment, the oil sump chamber 4
Fixed scroll 19 and rear housing 16 that define 1
The recess 19A is formed on the outer surface of the fixed side plate 19a of the fixed scroll 19 of the rear cover 38 and the rear cover 38.
The volume of 1 is increased along the axial direction. That is, as shown in FIGS. 1 and 2, a concave portion 19A is formed in the lower portion of the outer surface of the fixed side plate 19a so as to have a proper depth in the direction of the orbiting scroll 21 (leftward in FIG. 1) and its extension. The volume of the oil sump chamber 41 is increased by that amount. In addition, it is considered that an appropriate depth should normally be 1 mm or more.

At the center of the fixed scroll 19, the compression of the refrigerant gas progresses and the internal pressure of the compression chamber becomes the highest, so the fixed side plate 1
Higher strength than that of the peripheral portion is required for the joint portion between 9a and the fixed side spiral body 19b. Therefore, as shown in FIGS. 2 and 3, a recess 19A is formed between the contact wall 19c with the rear housing 16 and the contact wall 19d with the rear cover 38 so as to avoid that portion.

Therefore, as shown in FIG. 1, the thickness of the fixed side plate 19a is the same as that of the portion forming the discharge cavity 18 together with the rear housing 16, and the lower half portion excluding the portion, that is, the portion corresponding to the recess 19A. Is formed to be thinner than that.

The fixed side plate 19a and the fixed side spiral body 19b formed integrally with the fixed side plate 19a are formed by casting so as to obtain sufficient durability in terms of strength.

Thus, the fixed scroll 19, the rear housing 16 and the rear cover 3 which define the oil sump chamber 41 are formed.
8, the concave portion 19A is formed on the outer surface of the fixed side plate 19a of the fixed scroll 19, so that the volume of the oil sump chamber 41 can be increased without increasing the outer shape of the scroll compression portion 12. As a result, the function as an oil separator can be further enhanced.

Moreover, since the fixed scroll 19 is formed by casting, even if a thin portion is partially formed by providing the recess 19A in the fixed scroll 19, sufficient strength can be obtained regardless of the thin portion.

The recess in this embodiment is provided outside the circle having the same center as the discharge port and a radius three times larger than that of the discharge port.

[0031]

As described above, according to the scroll compressor of the first aspect of the present invention, the concave portion of the fixed side plate is provided outside the radius three times the radius of the discharge port to form the oil sump chamber. Then, while securing the necessary strength to the fixed side plate, since it was decided to thin the fixed side plate of the portion where the strength is unnecessary, it is possible to expand the volume of the oil sump chamber, as a result, as an oil separator. The function is improved.

According to the scroll type compressor of the second aspect, the volume of the oil sump chamber can be increased by forming a recess in a part of the fixed side plate so that the volume of the oil trap chamber can be increased. The volume of the oil sump chamber can be expanded without enlarging the outer shape, and as a result, the function as an oil separator is improved.

According to the scroll type compressor of the third aspect, since the fixed scroll is formed by casting, even if a thin portion is partially formed by providing the fixed scroll with a recessed portion, sufficient strength is ensured regardless of the thin portion. Can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view showing a compressor according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a fixed scroll showing an essential part of the present invention.

FIG. 3 is a right side view of FIG. 2.

FIG. 4 is an explanatory diagram showing a main part of a conventional scroll compressor.

[Explanation of symbols]

11 housing 12 Scroll compression unit 16 Rear housing 18 Discharge cavity 19 fixed scroll 19a Fixed side plate 19A recess 20 orbiting scroll 38 Rear cover 39 Oil separation chamber 41 oil sump chamber

   ─────────────────────────────────────────────────── ─── Continued front page       (56) Reference JP-A-11-82335 (JP, A)                 Japanese Patent Laid-Open No. 11-82326 (JP, A)                 JP-A-11-82352 (JP, A)                 Japanese Patent Laid-Open No. 11-82351 (JP, A)                 JP-A-11-82338 (JP, A)                 JP-A-11-93880 (JP, A)                 JP-A-4-125692 (JP, A)                 JP-A-4-124402 (JP, A)                 JP-A-3-33486 (JP, A)                 Japanese Patent Laid-Open No. 2-50193 (JP, A)                 JP 61-17490 (JP, A)                 JP 57-148086 (JP, A)                 JP 2001-329954 (JP, A)

Claims (3)

(57) [Claims] 1. A fixed scroll that constitutes a scroll compression portion in cooperation with an orbiting scroll is fixed to a housing, and a discharge cavity communicating with a discharge port is formed on an outer surface of a fixed side plate of the fixed scroll. A scroll type compressor having an oil separation chamber disposed downstream thereof and defining an oil sump chamber communicating with the oil separation chamber on the outer surface of the fixed side plate, wherein the oil sump chamber is a rear part of the housing. The lower wall of the fixed side plate is defined by an abutment wall that abuts the housing to form the discharge cavity in the upper part, and a recess is formed in the fixed side plate, and the recess is formed in the central portion of the fixed side plate. around the discharge port provided through said fixed plate, a scroll type compressor, characterized in that provided outside than three times the radius of said discharge exit port. 2. The volume of the oil sump chamber is increased by forming the fixed-side plate thickness of the portion corresponding to the concave portion to be thinner than the fixed-side plate thickness of the portion forming the discharge cavity. The scroll compressor described. 3. The scroll compressor according to claim 1, wherein the fixed scroll is formed by casting.