JP3074970B2 - 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 scroll compressor, and is particularly effective when used in a refrigerant compressor of an air conditioner for an automobile.

[0002]

2. Description of the Related Art Conventionally, a refrigerant compressor of a vehicle air conditioner is driven by a belt directly connected to an engine, so that a circulating flow rate of the refrigerant changes according to an engine speed. Therefore, it is set so as to secure an appropriate cooling capacity when the engine speed is low. Also,
In the case of a scroll-type compressor, the efficiency does not decrease even at high revolutions, and a constant amount of compression can be secured. There is a problem that the circulation flow rate increases and the temperature is too cold.

[0003]

As a method for solving the above problems, a method of opening and closing a suction port using a suction valve,
A method using a fluid clutch, a method in which a bypass mechanism is provided inside and a capacity is changed, and the like have been proposed, but all have had a problem that the structure is complicated.

[0004] Therefore, an object of the present invention is to provide a scroll-type compressor which has a simple structure, maintains a high capacity at a low rotation speed, and suppresses an excess capacity only at a high rotation speed.

[0005]

In order to achieve the above object, the present invention provides a housing, a suction space provided in the housing, and a spiral body formed on an end plate in the suction space. A fixed scroll member and a movable scroll member, the fixed scroll member and the movable scroll member are engaged with each other, and the movable scroll member revolves to compress the gas. A technical means is provided in which the housing is provided with a suction port closed by the end plate of the movable scroll member for a predetermined angle at the time.

[0006]

According to the above construction, the opening time of the suction port is shortened when the movable scroll member is rotated at a high speed by closing the suction port for a predetermined angle by the movable scroll member.
The amount of gas compression is limited.

[0007]

An embodiment will be described with reference to FIGS. The crankshaft 5 is instructed rotatably by bearings 11 and 12 held by the front housing 1. The crankshaft 5 is provided with a crank portion 6 disposed eccentrically from the rotation shaft by a predetermined amount. The movable scroll member 3 is rotatably supported on the crank portion 6 via a bearing 10. Accordingly, the movable scroll member 3 revolves by receiving the rotational driving force from the engine or the like to the crankshaft 5. Further, annular grooves 33 and 34 are provided on the end plate 8 of the movable scroll member 3 and the end face 9 of the front housing 1, respectively, and a plurality of spherical bodies 14 are provided between the two grooves. A prevention mechanism is provided to prevent the movable scroll member 3 from rotating.

A balance weight 7 is provided on the crankshaft 5 to compensate for a weight imbalance at the time of revolution of the movable scroll member 3 and the crank portion 6 in an eccentric state.
Has been fixed. Further, a shaft seal 13 is provided between the front housing 1 and the crankshaft 5 to prevent the refrigerant and the lubricating oil inside the compressor from leaking to the outside.

A fixed scroll member 4 is fixed to the rear housing 2 by bolts 18, and a discharge valve 15 is fixed to the fixed scroll member 4 together with a valve stop plate 16 by bolts 17. The rear housing 2 is fixed to the front housing 1 by bolts (not shown).

An inlet 20 is opened in the front housing 1, and an outlet 23 is opened in the rear housing 2. The suction port 20 is opened in the end face 9 of the front housing 1, and the opening 21 is provided in the movable scroll member for a predetermined rotation angle (about 90 degrees in this embodiment) during one revolution of the movable scroll member 3. 3 (FIG. 2, (a)), and the opening 21
The clearance between the movable scroll member 3 and the end plate 8 in the direction of the rotation axis is about 20 μm, which is small enough to prevent contact.

The space in the housing between the suction port 20 and the discharge port 23 is defined by an end plate 32 of the fixed scroll member 4. The left space of the end plate 32 is the suction space 22, and the right space of the end plate 32 is It becomes the discharge space 24.

[0012]

Since the compressor according to the present invention has the above-described configuration, the operation will be described below. FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1, and shows a state in which one revolution of the movable scroll member 3 revolves at about 90 ° intervals.
(C) and (d). 2 and 2C, the working chamber 25 is closed by the movable scroll member 3 and the fixed scroll member 4, the suction is completed, and the revolution of the movable scroll member 3 ((c) → (d) → (a) →
With (b)), the volume of the working chamber 25 decreases from the outer periphery toward the center, and the refrigerant inside is compressed. The compressed refrigerant pushes open the discharge valve 15 and is discharged from the discharge port 23 via the discharge space 24. At the same time, suction starts outside the working chamber 25, and when the state again becomes (c), the working chamber 25 is closed by both scroll members, so that suction is completed. However, in the state where the opening 21 of the suction port 20 is covered by the end plate 8 of the movable scroll member 3 (before and after FIG. 2A), between FIGS. And the suction amount of the refrigerant is suppressed. Therefore, in a state where the suction passage area is maintained to some extent (for example, from (b)) to when the suction is completed (time until (c)), the refrigerant is almost sucked. In such a configuration, when the rotation of the compressor is low, the end plate 8 is separated from the opening 21 of the suction port 20,
Since the opening 21 is open to the suction space 22 for a relatively long time, the refrigerant can be sufficiently sucked in. However, when the rotation of the compressor is high, the end 8 is frequently opened with the rotation. And the suction time is not short, so that the refrigerant cannot be sufficiently sucked into the working chamber 25. Therefore, the discharge amount of the compressed refrigerant at the time of high rotation is limited.

That is, in the compressor of the present embodiment, the refrigerant can be sufficiently sucked into the working chamber 25 at the time of low rotation, so that a high refrigerating capacity can be maintained. Is limited, supply of the refrigerant to the condenser in the refrigeration cycle is suppressed, and excess refrigeration capacity can be suppressed.

FIG. 3 shows a second embodiment. In the compressor shown in FIG. 3, a suction port 20 is provided in the rear housing 2, and a crescent-shaped groove 30 is formed in an opening 21 of the suction port 20. The end plate 8 of the movable scroll member 3 is formed with a crescent-shaped convex portion 31 that forms a pair with the crescent-shaped groove 30. It protrudes and retreats into the groove 30 (FIG. 4). The crescent-shaped groove 30 and the clearance in the rotation axis direction of the crescent-shaped convex portion 31 are so small that they do not contact each other.

With the above structure, the opening area of the opening 21 of the suction passage can be changed in accordance with the revolving motion of the movable scroll member 3, so that the time from when the suction passage area is sufficiently secured to when the suction is completed is optimal. By forming the crescent-shaped groove 30 and the crescent-shaped protrusion 31 as described above, the same effect as in the first embodiment can be obtained.

The structure of the opening of the suction port is shown in FIG.
The configuration is not limited to the configuration shown in FIG. 3 and may be any configuration as long as the opening is intermittently closed by the revolution of the movable scroll member.

Further, in the embodiment of the present invention, the case of compressing the refrigerant has been described. However, the medium is not limited to the refrigerant, but may be any medium having a compressibility such as air. Absent.

[0018]

According to the present invention having the above-described structure, the inflow of gas into the working space at the time of high rotation can be limited without adding a complicated structure, and the excess capacity can be limited. Becomes

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing the internal configuration of a scroll compressor according to an embodiment of the present invention.

FIGS. 2A, 2B, 2C, and 2D are cross-sectional views taken along the line AA in FIG. 1, illustrating a revolving position of a scroll member and a closed state of a suction port;

FIG. 3 is a longitudinal sectional view showing the internal configuration of a scroll compressor according to another embodiment of the present invention.

4 (a), (b), (c), and (d) are cross-sectional views taken along the line BB in FIG. 3 showing a revolving position of a scroll member and a closed state of a suction port.

[Explanation of symbols]

 Reference Signs List 3 movable scroll member 4 fixed scroll member 8 end plate 32 end plate 20 suction port 21 opening 22 suction space

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-261694 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F04C 18/02 311 F04C 29/00

Claims (1)

(57) [Claims] 1. A fixed scroll member comprising: a housing; a suction space provided in the housing; and a fixed scroll member and a movable scroll member each comprising a spiral body formed on an end plate in the suction space. And a movable scroll member is meshed with each other, and the movable scroll member revolves to compress the gas. In the scroll compressor, the end plate of the movable scroll member is used for a predetermined angle when the movable scroll member revolves. A scroll type compressor, wherein a closed suction port is provided in the housing.