JPH04128580A - Scroll compressor - Google Patents

Abstract

PURPOSE:To highly seal both scrolls by arranging a fixed scroll so that the inner pressure of a discharge chamber is applied as the back pressure toward a rotary scroll side with respect to the fixed scroll, and supporting the fixed scroll displaceably in the axial direction. CONSTITUTION:The gas sucked through an intake port 7 is compressed by a scroll section 1 then discharged to a discharge chamber 4 and sent to the outside from a delivery pipe 6 in a scroll compressor, a fixed scroll 8 is coupled with an upper circular member 10 fixed to a container 3, rotation is prevented by the coupling between a pair of recesses 14 formed on the outer periphery of the fixed scroll 8 and projections 15 formed on the inner periphery of the upper circular member 10, and the displacement in the axis Qa direction is allowed within the margin range of a gap 22 with a pressing ring 21. The fixed scroll 8 functions as part of the forming wall of the discharge chamber 4, the inner pressure (p) of the discharge chamber 4 is applied to the back face of the fixed scroll 8 as the back pressure applied to a rotary scroll 9 side, and the seal between both scrolls 8, 9 is highly attained.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a scroll compressor.

[Conventional technology]

Conventionally, as a technology to prevent damage due to liquid compression in scroll compressors, intermediate pressure during compression in the scroll section is guided to the back side of the orbiting scroll through pores, and this intermediate pressure is used to move the orbiting scroll toward the scroll shaft. By pressing the fixed scroll side in the core direction, it seals between both scrolls, and also fixes the orbiting scroll in the scroll axis direction against the above intermediate pressure against abnormal pressure generated in the scroll part during liquid compression. There is a method in which damage is avoided by causing the escape movement to move away from the scroll (Conventional Example 1).

In addition, even if the orbiting radius of the orbiting scroll is made variable and the orbiting radius is not normally maintained at a radius that provides a sufficient seal between both scrolls, if abnormal pressure is generated in the scroll section due to liquid compression, the orbiting radius of the orbiting scroll will be adjusted accordingly. There is also a device in which damage is avoided by changing the value to the decreasing side (Conventional Example 2).

[Invention or problem to be solved]

However, in the technology of Conventional Example 1, in addition to an airtight structure against high pressure such as the internal pressure of the discharge chamber into which compressed gas flows into the scroll part, an airtight structure against intermediate pressure acting on the back surface of the orbiting scroll is also required. Moreover, the airtight structure as a whole is extremely complicated, which makes it difficult to manufacture and increases the cost of the device.

On the other hand, in the technology of Conventional Example 2, the drive structure (especially the crank structure) of the orbiting scroll is complicated in order to make the orbiting radius of the orbiting scroll variable, which makes it difficult to manufacture and increases the equipment cost. There was a growing problem.

An object of the present invention is to use a rational and simple structure to achieve sufficient sealing between both scrolls and to reliably prevent damage due to liquid compression.

[Means to solve the problem]

The first characteristic configuration of the scroll compressor according to the present invention is that the compressed gas in the scroll section is in a state where the internal pressure of the discharge chamber into which it flows acts as a back pressure against the fixed scroll toward the orbiting scroll. The scroll is disposed and the fixed scroll is supported so as to be freely displaceable in the direction of the scroll axis, and its functions and effects are as follows.

[For production]

In other words, in the above-mentioned first characteristic configuration, the fixed scroll is normally rotated by causing the internal pressure of the discharge chamber to act on the fixed scroll supported so as to be freely displaceable in the direction of the scroll axis as back pressure directed toward the orbiting scroll. It can be pressed against the scroll to create a high degree of sealing between both scrolls.

During liquid compression, the fixed scroll is moved against the internal pressure of the discharge chamber to the side away from the orbiting scroll in the direction of the scroll axis, thereby creating a gap between the two scrolls. By making the seal incomplete, it is possible to reliably avoid equipment damage due to abnormal pressure during liquid compression.

〔Effect of the invention〕

That is, according to the first characteristic configuration of the present invention, it is a rational configuration that utilizes the originally generated discharge chamber pressure, and a simple structure that supports the fixed scroll so as to be freely displaceable in the direction of the scroll axis. With the improvement, damage to the device during liquid compression can be reliably avoided because there is usually no sufficient seal between both scrolls, and as a comparison with the conventional technology, the conventional example 1 mentioned above, which requires an airtight structure against intermediate pressure, Compared to conventional example 2, which requires a special drive structure to make the turning radius variable, the device structure is simplified and manufacturing is facilitated.
In addition, in order to reduce production costs, both normal screen
It has now been possible to reliably achieve both sealing between the tubes and prevention of damage during liquid compression.

Further, in contrast to the conventional example 1 described above, in which the orbiting scroll is pressed against the mechanically fixed fixed scroll by intermediate pressure to seal between both scrolls, according to the first characteristic configuration of the present invention, intermediate pressure is applied. Since the fixed scroll is pressed against the orbiting scroll by the internal pressure of the discharge chamber which is higher than the pressure in the discharge chamber, and the sealing between both scrolls is performed, there is an advantage that a higher degree of sealing between both scrolls can be achieved in normal times.

[Second characteristic configuration of the present invention] A second characteristic configuration of the scroll compressor according to the present invention is that, apart from the internal pressure of the discharge chamber, a biasing means for biasing the fixed scroll toward the orbiting scroll is provided. This second characteristic configuration is used to ensure that the space between both scrolls is sealed by the biasing means described above even before the internal pressure of the discharge chamber starts increasing at the start of compression operation. By doing so, it is possible to maintain high start-up performance at the start of compression operation.

〔Example〕

Next, an example will be described.

Figures 1 and 2 show the device structure of a scroll compressor that compresses refrigerant gas in a heat pump.The main components include a scroll part (1) and a motor (2) installed inside a container (3), and a scroll compressor that compresses refrigerant gas in a heat pump. A discharge chamber (4) having an airtight structure is formed at the upper end of the portion (1) and inside the container (3).

(5) is a return pipe for gas, (6) is a delivery pipe for compressed gas, gas is sucked into the scroll part (1) from the suction port (7) and compressed in the scroll part (1), and It is discharged from the scroll portion (1) to the discharge chamber (4), and from the discharge chamber (4) to the delivery pipe (6).

The scroll part (1) has a scroll wall (8a) on the lower surface side.
The fixed scroll (8) is arranged at the upper part and the orbiting scroll (9) is arranged at the lower part and the scroll wall (9a) is formed on the upper surface side.The fixed scroll (8) and the orbiting scroll (9) are The phases of both scroll walls (8a) and (9a) in the spiral direction are shifted by 180 degrees from each other, and the other scroll wall (9a) is inserted between one adjacent scroll wall (8a), so that they can be combined vertically. be.

The fixed scroll (8) is fitted into the upper annular member (10) fixed to the container (3) and fixed so as not to be displaceable in the radial direction, while the orbiting scroll (9) is attached to the intermediate annular member (10). In the support that is sandwiched between the member (lla) and the lower annular member (llb) to prevent displacement in the direction of the scroll axis (Qb), the motor (2) can be displaced in the radial direction within a predetermined range. The rotation of the crank mechanism (12)
by transmitting the information to the orbiting scroll (9) via the
With the orbiting scroll (9) eccentric from the scroll axis (Qa) of the fixed scroll (8) by a predetermined dimension (e), the scroll I [[l core (
Qa) It has a configuration in which it rotates around Qa).

That is, by the above-mentioned orbiting operation of the orbiting scroll (9), the steps shown in FIG. 2 (a), (0), (c), and (d) are repeated in that order. ), a crescent-shaped compression chamber (S) is sequentially formed between both scroll walls (8a), (9a) from the large diameter end of scroll wall (8a), (9a).
, while continuously shifting to the small diameter side of (9a),
In the transition process, the volume of the compression chamber (S) is gradually reduced,
It is configured to compress the gas within the compression chamber (S).

The compressed gas finally passes through the discharge hole (13) formed in the scroll axis (Qa) of the fixed scroll (8).
It is discharged from the discharge chamber (4).

Note that the suction port (7) faces near the large-diameter end of the scroll wall (8a) of the fixed scroll (8),
The discharge chamber (4) also includes a container (3) and an upper annular member (1).
0) over the entire circumference (in this example, by welding), the container (3) is airtight with respect to itself and other parts.

The fixed scroll (8) has a pair of recesses (14) formed on its outer periphery and a protrusion (15) formed on the inner periphery of the upper annular member (10), which engages with each other to control the rotating operation of the orbiting scroll (9). The orbiting scroll (9) has a pair of grooves (16) extending in the radial direction formed on its lower surface and a convex portion ( Rotation is prevented by engagement with 18).

To explain the anti-rotation ring (17) in more detail, the lower surface of the anti-rotation ring (17) has a convex portion (18) on the upper surface side.
) is a pair of lower surface protrusions (19) with a 90° phase shift.
The lower annular member (1b) is formed by engaging the lower surface side protrusion (19) with a pair of radially extending grooves (20) formed in the lower annular member (llb).
The displacement movement of the anti-rotation ring (17) relative to 1) is performed only in the groove direction of its groove (20) (the direction perpendicular to the groove direction of the groove (16) formed on the lower surface of the orbiting scroll (9)). There is a configuration that allows this.

In other words, the convex part (18) on the upper surface side and the orbiting scroll (9)
The orbiting scroll (
9) and the anti-rotation ring (17) only in the groove direction of the concave groove (16) on the lower surface of the orbiting scroll (9), and as mentioned above, the lower annular displacement movement is allowed only in the direction perpendicular to the groove direction. By allowing the rotation prevention ring (17) to displace with respect to the member (llb), the orbiting scroll (9) is rotated while preventing its rotation in response to power transmission from the crank mechanism (12). There is.

Regarding the support of the fixed scroll (8), as mentioned above, the fixed scroll (8) is fitted inside the upper annular member (10), while the presser ring (2I ) to prevent the fixed scroll (8) from being pulled out upwards, and when installing this retaining ring (21), it is necessary to prevent displacement in the direction of the scroll axis (Qb). The stationary scroll (8) is in proper contact with the orbiting scroll (9) which is supported in a state in which both scrolls (8), (
9) Seal between the scroll wall (8a), (
9a) In a state where the airtightness of the compression chamber (S) formed between them is sufficiently maintained due to the compression function), the fixed scroll (
A gap (2) with a predetermined dimension (d,
2) The mounting position of the holding ring (21) is set so that displacement of the fixed scroll (8) in the direction of the scroll axis (Qa) is permitted by the flexibility of this gap (22). It has been done.

In other words, since the fixed scroll (8) fitted inside the upper annular member (10) also functions as part of the wall forming the discharge chamber (4), the back surface (top surface) of the fixed scroll (8) is Either the internal pressure (p) of the chamber (4) acts as a back pressure toward the orbiting scroll (9), or the fixed scroll (8) is supported so as to be freely displaceable in the direction of the scroll axis (Qa) as described above. During normal compression function, the discharge chamber (
By pressing the fixed scroll (8) against the orbiting scroll (9) using the internal pressure (p) of 4), both scrolls (
8) and (9), and during liquid compression caused by suction of liquid phase refrigerant, the abnormal pressure generated in the scroll part (1) (specifically, the compression chamber for liquid compression) is achieved. The fixed scroll (8) is moved between the fixed scroll (8) and the discharge chamber (4).
against the internal pressure (p) of the scroll axis (Qa) to move away from the orbiting scroll (9) (upwards), thereby sealing between the scrolls (8) and (9). By making it incomplete, it is possible to avoid damage to the device due to abnormal pressure during liquid compression.

In addition, the scroll axes (Qa) and (Qb) are arranged vertically, and the fixed scroll (8) is replaced by the orbiting scroll (9).
By locating it on the upper side, the fixed scroll (8) is gravity-biased toward the orbiting scroll (9) by its own weight, in addition to the internal pressure (p) of the discharge chamber (4). As a result, even before the internal pressure (p) of the discharge chamber (4) starts to increase at the start of compression operation, the above-mentioned gravitational force causes pressure to rise between the scrolls (8) and (9). The seal is maintained properly to maintain high startup performance at the start of compression operation.

The lower end of the container (3) serves as a reservoir for refrigeration oil (L) used for lubricating and cooling various parts.
) is operated by the crank mechanism (1) by an appropriate circulation means (not shown).
2), the bearing part (23), and other necessary parts.

[Another example]

Next, another example will be listed.

(11 In addition to the internal pressure (p) of the discharge chamber (4), gravity biasing was employed in the above embodiment as a biasing means for biasing the fixed scroll (8) toward the orbiting scroll (9). Or, instead of this, a biasing means for biasing the fixed scroll (8) toward the orbiting scroll (9) separately from the internal pressure (p) of the discharge chamber (4) using a spring, an elastic member, etc. Alternatively, this type of urging means may be omitted and the fixed scroll (8) may be urged toward the orbiting scroll (9) only by the internal pressure (p) of the discharge chamber (4). may be adopted.

(2) A specific fixed scroll (8) so that the internal pressure ([]) of the discharge chamber (4) or the fixed scroll (8) acts as a back pressure toward the orbiting scroll (9). Various configuration changes are possible for the arrangement configuration.

In addition, the fixed scroll (8) is aligned with the scroll axis (Qa).
Various improvements and configuration changes can be made to the specific support structure for supporting the device so that it can be freely displaced in the directions.

(3) The orientation of the scroll axes (Qa) and (Qb) is not limited to vertical orientation, but may be horizontal or diagonal.

Alternatively, a configuration may be adopted in which the fixed scroll (8) is arranged below the orbiting scroll (9).

(4) The gas to be compressed is not limited to the refrigerant gas of a heat pump, and the present invention can be applied to Schrono L compressors used for various compression purposes in various fields.

It should be noted that the present invention is not limited to the structure of the attached drawings by adding numerals in the claims for convenient comparison with the drawings.

[Brief explanation of drawings]

1 and 2 show an embodiment of the present invention, FIG. 1 is a cutaway sectional view, and FIG. 2 (0, (o), (c). (1)...scroll part, (4)...discharge chamber, (8)...fixed scroll, (9)...
Rotating flow/l, (Qa)...scroll shaft core,
(p)...-Internal pressure.

Claims (2)

[Claims] 1. The internal pressure (p) of the discharge chamber (4) into which gas compressed in the scroll part (1) flows, or the fixed scroll (8
), the fixed scroll (8) is arranged in a state where it acts as a back pressure toward the orbiting scroll (9), and the fixed scroll (8) is supported so as to be freely displaceable in the direction of the scroll axis (Qa). A scroll compressor. 2. A scroll compressor provided with a biasing means for biasing the fixed scroll (8) toward the orbiting scroll (9) in addition to the internal pressure (p) of the discharge chamber (4).