JPH05180177A - Scroll compressor - Google Patents

Abstract

PURPOSE:To provide a highly reliable scroll compressor by forming a cross-section of a recessed groove so that it gradually decreases toward the bottom of the groove and also engaging a chip seal formed according to its cross-section. CONSTITUTION:A chip seal 26 is moved in Y-direction and pressed against a base plate by a pressure produced in normal compressive operation and, when a liquid refrigerant is filled into a compressive chamber, it receives a pressure of several to several ten times a pressure produced in normal operation from X-direction and an excessive stress is produced at a corner 25c of a groove side face 25a and a groove bottom face 25b. To avoid excessive stress concentration, the corner 25c is connected with a smooth curve of a specified radius of curvature. A chip seal 22 is also made in a form along the cross-section of a recessed groove 25 to reduce a clearance 27 produced when the chip seal 26 is moved in a direction as low as possible. Thus a leaking area is reduced as compared with the conventional clearance to suppress leakage from high- pressure side to low-pressure side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor in which a seal portion inside a compression chamber is improved.

[0002]

2. Description of the Related Art FIG. 3 shows a conventional scroll compressor proposed in Japanese Patent Application No. 61-283406.
In the figure, reference numeral 1 denotes a fixed scroll, which is a base plate portion 1a.
A spiral projection 1b is formed on the lower surface of the
The tip seal 3 is inserted in the groove 2 formed in the end face of b.

Reference numeral 4 denotes an orbiting scroll, which is a base plate portion 4a.
The spiral projection 4b is formed on the upper surface of the
A tip seal 6 is inserted into the groove 5 formed on the end surface of b. Further, a swing shaft portion 4c projects below the central portion of the base plate portion 4a. 9 is a compression chamber formed by combining the spiral projections 1b and 4b, and 10 is each scroll 1, 4
1, an intake port formed on the outer periphery of the main scroll 12, a protrusion port provided in the center of the base plate portion 1a of the fixed scroll 1, a main shaft 12, and an eccentric hole in the large diameter portion 12a at the upper end of the main shaft 12. 12b is formed. A rocking bearing 13 is fitted in the eccentric hole 12b and supports the rocking shaft portion 4c in the radial direction.
Reference numerals 4 and 15 denote a motor rotor and a motor stator that drive the main shaft 12, 16 an Oldham coupling that regulates the orbiting scroll 4 so that the orbiting scroll 4 does not rotate when the main shaft 12 is driven, and 17 an airtight container that houses each component. , 18
Is a suction pipe fixed to the closed container 17, and 19 is a discharge pipe fixed to the fixed scroll, and delivers the compressed gas from the discharge port 11 to the outside of the closed container 17.

Reference numeral 20 denotes a bracket, which supports the fixed scroll 1 and the orbiting scroll 4 in the recess 20a so that the orbiting scroll 4 can swing, and an Oldham coupling 16 is provided.
Further, the large diameter portion 12a of the main shaft 12 is rotatably supported via a bearing 21. Further, this bracket 20 has an oil return hole 20.
b and the gas passage 20c. Reference numeral 22 supports the bracket 20, the motor stator 15 and the main shaft 12
Is a bracket that rotatably supports the oil return hole 22a and the gas passages 22b and 22c. Reference numeral 12c is an eccentric oil supply hole provided eccentrically through the main shaft 12, 23 is an oil cap attached to the lower end of the main shaft 12, and 24 is lubricating oil.

Next, the operation will be described. In the conventional scroll compressor described above, the main shaft 12 rotates when the motor rotor 15 rotates, and the orbiting scroll 4 revolves while being prevented from rotating by the Oldham coupling 16. This allows the gas passages 22c, 22b, 2
The suction gas is taken into the compression chamber 9 through the suction port 0c and the suction hole 10, gradually compressed and discharged from the discharge port 11 to the discharge pipe 19.

In the scroll compressor which performs the compression action from the compression chamber 9 on the outer peripheral side toward the discharge port 11 on the inner peripheral side, the end face of the scroll side plate and the end face of the scroll side plate are considered in view of providing good compression efficiency. Sealing means is provided between the end face of the scroll and the scroll end plate facing the end face. A tip seal has been widely used as a sealing means of this type.

Such sealing means will be described with reference to FIGS. 4 and 5. In the figure, the orbiting scroll 4 is composed of a spiral protrusion 4b having a concave groove 5 extending in the spiral direction and a scroll base plate portion 4a provided on the lower end surface of the spiral protrusion 4b.

Reference numeral 6 denotes a tip seal which partially faces the recessed groove 5, and its width is formed slightly smaller than the width of the recessed groove 5. The spiral projection 4b and the base plate portion of the fixed scroll 1 facing the spiral projection 4b ( (Not shown). Reference numeral 7 is a communication port that communicates with the inside of the concave groove 5 and the high pressure region of the center of the spiral. In the tip seal configured as described above, as shown in FIG. 5, the high-pressure fluid that has flowed in from the lower end surface of the tip seal 6 and the concave groove 5 and the gap (not shown) between the tip seals 6 flows into the gap. 8 can be formed and the chip seal 6 can be pressed axially from below to obtain a seal.

[0009]

The conventional groove and tip seal are generally formed in a rectangular shape in cross section, and the normal operation is as described above. However, in scroll compressors for refrigeration and air conditioning that use CFC gas or the like, there are many cases where CFC gas is liquefied and accumulated in a closed container when the compressor is stopped.
This is often the case in winter mornings when the outside air temperature has dropped, and a compressor with a relatively large heat capacity has little temperature fluctuation when stopped, so it collects refrigerant gas in other refrigeration cycles,
This is a phenomenon that occurs due to liquefaction.

When the compressor is started in this state, the compressor tries to compress the refrigerant in the liquid state in the compression chamber. Then, a pressure several times to several tens of times the pressure normally generated is generated in the compression chamber, and due to the increase in the starting torque, the motor starting failure and the protection circuit by the abnormal pressure prevention device are activated, and the compressor is stopped. It is supposed to do. On the other hand, the above-mentioned ultra-high pressure is applied to the spiral protrusion in the compression chamber to try to deform the protrusion. Further, since the groove is naturally thinner than the spiral protrusion, the recess groove may be damaged due to a larger stress than that of the spiral protrusion. If the groove is damaged, compression becomes impossible and the tip seal also pops out of the groove, resulting in a compressor failure.

Further, during the normal operation, as described above, the high pressure fluid flows through the gap between the lower end surface of the tip seal 3 and the groove 2 in order to press the tip seal 3 in the axial direction from below. That is, the high-pressure fluid, which has been compressed, flows into the low-pressure fluid region, resulting in reduced capacity and increased compression power.

The present invention has been made for the purpose of solving the above-mentioned problems, and prevents the concave groove from being damaged even when a liquid state refrigerant enters the compression chamber, and prevents the concave groove from being damaged during normal operation. It is an object of the present invention to obtain a scroll compressor whose performance can be minimized.

[0013]

In order to achieve the above object, the following constitution is adopted. That is, a fixed scroll and an orbiting scroll that have a concave groove provided between the end surface of each spiral projection and the end surface of each base plate facing the spiral projection and are combined so as to form a discharge chamber and a compression chamber with each other. In a scroll compressor provided with a scroll assembly consisting of and a tip seal mounted in a groove of the scroll assembly through a gap, the cross-sectional shape of the groove is gradually increased toward the groove bottom of the groove. Forming to decrease,
The tip seal formed according to the cross-sectional shape of the groove is engaged with the groove.

A fixed scroll having end faces of the spiral side plates and concave grooves provided between the end faces of the base plates facing the spiral side plates, which are combined so as to form a discharge chamber and a compression chamber with each other. In a scroll compressor including a scroll assembly including a scroll scroll and an orbiting scroll, and a tip seal mounted in a groove of the scroll assembly with a groove bottom and a gap, a cross-sectional shape of the groove is a semicircle. The tip seal may have a semicircular shape that is substantially the same as the groove.

[0015]

With the above-described structure, in the scroll compressor of the present invention, even when the liquid refrigerant is compressed, the rigidity of the concave groove is high and stress is not concentrated on the side and bottom corners of the groove. Therefore, it is not damaged. Further, by making the cross section of the groove and the tip seal semi-circular, the gap between the groove and the bottom surface of the tip seal is made as small as possible.

[0016]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. The description of the same parts as those of the conventional scroll compressor will be omitted. Further, the reference numerals in the figure are the same as those of the conventional scroll compressor. In FIG. 1, reference numeral 25 denotes a concave groove, which is provided at the tip of the spiral protrusions 1 a and 4 a of the fixed scroll 1 and the orbiting scroll 4. 26 is fitted in the groove,
It is a tip seal that can be moved vertically and horizontally.

In the figure, the tip seal 26 moves in the Y direction and is pressed against the base plates 1b and 4b by the high pressure generated during the normal compression operation. Excessive stress is generated in the corner portions 25c of the groove side surface 25a and the groove bottom surface 25b by receiving a pressure several times to several tens of times that during operation. Therefore, it is possible to avoid excessive stress concentration by connecting the corners 25c, which are conventionally angled, with a smooth curve having a certain curvature.

Further, the tip seal 26 is also formed in a shape that follows the cross-sectional shape of the concave groove 25 as shown in the figure, and the gap 27 generated when the tip seal 26 moves in the Y direction is made as small as possible. .. This was further advanced in Figure 2
The cross-sectional shape is a semi-circular shape as shown in Fig. 3, and the leakage area is smaller than the conventional gap, and the leakage from high pressure to low pressure can be suppressed.

[0019]

As described above, according to the present invention, the cross sectional shape of the concave groove provided at the tip of the spiral protrusion of the scroll compressor is gradually reduced toward the groove bottom of the concave groove. Since the side surface and the bottom surface are connected by a smooth curve, stress is not concentrated at the corners of the groove, and a highly reliable scroll compressor without damage to the groove can be obtained.

By making the cross section of the groove and the tip seal semi-circular, it is possible to minimize leakage of high pressure fluid during compression operation to the low pressure side through the gap between the groove and the tip seal. Therefore, performance degradation can be avoided.

[Brief description of drawings]

FIG. 1 is a sectional view of a groove portion provided at an end portion of a spiral protrusion according to an embodiment of the present invention.

FIG. 2 is a sectional view of a groove portion provided at an end portion of a spiral protrusion according to another embodiment of the present invention.

FIG. 3 is a vertical cross-sectional view showing a conventional scroll compressor.

FIG. 4 is a plan view of a conventional rocking scroll.

5 is a vertical cross-sectional view of FIG.

[Explanation of symbols] 1 fixed scroll 2 orbiting scroll 25 concave groove 26 tip seal

Claims (2)

[Claims] 1. A fixed scroll having a groove formed between the end surface of each spiral projection and the end surface of each base plate opposed to the spiral projection, and each of which is combined so as to form a discharge chamber and a compression chamber. In a scroll compressor provided with a scroll assembly including an orbiting scroll and a tip seal mounted in a groove of the scroll assembly through a gap, a cross-sectional shape of the groove is formed in a groove bottom of the groove. A scroll compressor characterized in that the tip seal is formed so as to gradually decrease toward the bottom, and a tip seal formed in accordance with the cross-sectional shape of the groove is engaged with the groove. 2. A fixed scroll having an end face of each spiral side plate and a concave groove provided between the end faces of the respective base plates facing the spiral side plate, each of which is combined so as to form a discharge chamber and a compression chamber. In a scroll compressor including a scroll assembly including a scroll scroll and an orbiting scroll, and a tip seal mounted in a groove of the scroll assembly with a groove bottom and a gap, a cross-sectional shape of the groove is a semicircle. And a cross section of the tip seal has a semicircular shape that is substantially the same as the groove.