JPH07189942A - Scroll compressor - Google Patents

Abstract

PURPOSE:To provide a scroll compressor of high efficiency and low noise by disposing a discharge valve in a scroll compressor, eliminating a back flow phenomenon of discharge fluid in the case of insufficient compression, reducing impact noise to be generated in closing the discharge valve, and restraining a discharge loss. CONSTITUTION:Two discharge valves 221 each made of an elastic plate fixed at one end thereof in the longitudinal direction to a fixed scroll 11 are laminated in a discharge unit, thus opening or closing a discharge port 112. A hole the same or larger in size as or than the discharge port 112 is formed on a portion in abutment against the discharge port 112 of the fixed scroll on one in contact with the fixed scroll 11 of the two discharge valves 221.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor.

[0002]

2. Description of the Related Art A scroll compressor includes a fixed scroll having spiral vanes and an orbiting scroll having spiral vanes substantially symmetrical with the spiral vanes of the fixed scroll.
By engaging in a state of being shifted by 80 degrees, a plurality of compression work spaces that are symmetrical in the radial direction are formed at the same time. Here, since the orbiting scroll has its rotation restrained by the rotation restraint component, when the orbiting scroll orbits with respect to the fixed scroll with the orbiting radius r, the fluid taken in at the outer peripheral portion in the radial direction of the spiral blade is compressed. As the volume of the working space decreases continuously, it is compressed towards the center. When the orbiting motion continues, the symmetrical work space compressed to the vicinity of the central portion communicates with each other, and the compressed fluid is discharged from the discharge port provided near the central portion of the fixed scroll.

A scroll compressor is a kind of positive displacement compressor that performs a compression work based on the above-mentioned principle. The pressure of the fluid discharged is the pressure of the fluid taken in at the outer peripheral portion in the radial direction of the spiral blade and the pressure of the spiral blade. It is determined by the number of turns and the specific heat ratio.

By the way, in the scroll compressor based on the principle as described above, the symmetric compression work space compressed to the vicinity of the central portion is discharged at the moment when it communicates with the discharge port provided near the central portion of the fixed scroll. The pressure in the compression work space may be lower than the pressure. That is, there may be a case of insufficient compression. Therefore, a phenomenon occurs in which the fluid flows back from the discharge space into the communicating compression work space through the discharge port. When such a phenomenon occurs, there is a problem that pressure loss and energy loss occur, and the fluctuation of the discharge pressure increases.

In particular, in a relatively small scroll compressor whose size in the radial direction is limited, it is generally difficult to increase the number of spiral blades, and the number of spiral blades is smaller than that of medium and large scroll compressors. It is necessary to design as few as possible. Therefore, depending on the pressure condition, the above-mentioned insufficient compression state is likely to occur, resulting in a decrease in efficiency.

In order to solve the above problems, there is a means for providing a discharge valve at the discharge port of the fixed scroll, as disclosed in Japanese Patent Laid-Open No. 55-35151. A sectional view of an example of this means is shown in FIG. As a result, even in the case of the above-described insufficient compressor, the discharge valve 221 is closed when the pressure in the bilaterally symmetrical compression work space after communicating with the discharge port 112 is equal to or lower than the discharge pressure, and is larger than the discharge pressure. When this happens, the discharge valve opens, so there is no phenomenon of backflow of fluid into the communicating compression work space, and problems such as pressure loss and energy loss do not occur.

[0007]

However, in the conventional discharge valve as described above, when the rigidity of the discharge valve is weak,
When the compressed fluid is discharged to the discharge space, the projection valve lifts up greatly, and at the moment of closing, the discharge valve collides strongly with the surface of the fixed scroll on the discharge space side, and at this moment a large impact sound is generated and the scroll The compressor has a problem of impairing the inherent quietness of the compressor.

On the contrary, when the discharge valve has a high rigidity,
Since the ejection valve is hardly lifted up, the discharge stroke is not smoothly performed, and the pressure in the compression work space rises to a level considerably higher than the pressure in the discharge space. As a result, extra compression power is required, which causes a problem that a large discharge loss occurs.

The present invention solves the above-mentioned conventional problems by providing a discharge valve in a scroll compressor to eliminate the insufficient compression phenomenon and at the same time reduce the impact noise that occurs when the discharge valve is closed and discharge it. It is an object of the present invention to provide a scroll compressor that suppresses loss, is highly efficient, and has low noise.

[0010]

In order to solve the above-mentioned problems, the present invention has a structure in which two discharge valves are arranged in a stacked manner, and among the two discharge valves, the discharge valve in contact with the fixed scroll is A hole that is the same as or larger than the ejection port is formed in the portion of the fixed scroll that corresponds to the ejection port.

Further, of the two discharge valves, the discharge valve in contact with the fixed scroll has a concave or convex shape with respect to the surface of the fixed scroll on which the discharge valve is fixed.
Alternatively, the discharge valve is shaped so that the vicinity of the tip on the side opposite to the side where it is fixed to the fixed scroll has a gap with the fixed scroll in advance.

Further, the portion of the discharge port in contact with the discharge valve is made wider than that on the compression work space side.

[0013]

In the present invention, since two discharge valves are arranged and the lower discharge valve is provided with a hole that is the same as the discharge port or larger than the discharge port, the apparent spring constant of the discharge valve is the discharge valve 1. It is the same as when it was a piece. Further, since the two discharge valves are arranged, the contact surfaces of the upper discharge valve and the lower discharge valve, and the contact surfaces of the lower discharge valve and the fixed scroll buffer each other, and they serve to soften the impact when the discharge valve is closed. . In addition, the compressed fluid or the lubricating oil enters between the respective contact surfaces and acts like a cushion to make the cushioning effect more effective.

Further, of the two discharge valves, the discharge valve in contact with the fixed scroll has a concave or convex shape with respect to the surface of the fixed scroll on which the discharge valve is fixed.
Alternatively, by making the discharge valve near the tip on the side opposite to the side fixed to the fixed scroll to have a gap with the fixed scroll in advance, when the upper discharge valve is closed, first hit a part of the lower discharge valve. , At this time, the momentum at which the upper discharge valve closes weakens. Next, the lower discharge valve has a warped shape,
Since the tip is floating, the spring constant of the lower discharge valve is effective when the discharge valve is closed thereafter, and the discharge valve is slowly closed. Further, since the discharge valve is warped or the tip is floated, compressed fluid or lubricating oil easily enters each contact surface.

Further, by making the portion of the discharge port in contact with the discharge valve wider than the side of the compression work space, the discharge process can be carried out smoothly, and by widening only the discharge valve side of the discharge port, dead It is possible to minimize the loss due to the increase in volume.

As a result, the discharge valve does not collide strongly with the fixed scroll when the valve is closed, and the discharge resistance due to the discharge valve does not occur.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A scroll compressor according to an embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, the compression mechanism includes a spiral blade 11
1 includes a fixed scroll 11, a swirl scroll 10 in which a spiral blade 101 is formed on a swirl end plate 102, and a rotation restraint component 12. The fixed scroll 11 is fixed to a hermetic container 17 together with a bearing member 13. . A shaft 103 is provided on the side of the orbiting end plate 102 of the orbiting scroll 10 opposite to the spiral blade 101, and the shaft 103 is rotatably supported by a bearing portion 131 of a bearing member 13 and a ball bearing bearing portion 15. 14
Is supported by an eccentric hole portion 141 formed at one end of the.
A sealed container 17 is provided between the bearings 131 and 15 of the main shaft 14.
Motor 16 including a stator 161 fixed to the main shaft 14 and a rotor 162 fixed to the main shaft 14 and rotatable with the main shaft
Are arranged.

Therefore, by driving the electric motor 16, the main shaft 14 rotates, and the eccentric hole portion 141 of the main shaft 14 performs eccentric rotary motion. As a result, the orbiting scroll 10 tries to perform a rotation motion, but since the rotation is restricted by the rotation constraint component 12, the main shaft 14 and the orbiting scroll 1 are rotated.
The turning motion is performed with the radius of the axis distance from the shaft portion 103 of 0. As a result, a plurality of bilaterally symmetrical compression working spaces 19 formed by meshing the spiral blades 111 of the fixed scroll 11 and the spiral blades 101 of the orbiting scroll 10 with each other by 180 ° are sucked from the suction pipe 18. The fluid is taken in through the suction port 113, and the compression work is continuously performed as the volume of the compression work space 19 decreases. Then, when compressed to near the center, the symmetric compression work space 19 communicates with the discharge port 112. When the pressure in the compression work space 19 at the moment of communication is higher than the pressure in the discharge space 20, the discharge valve 221 made of an elastic plate opens to the discharge space 20 side so that the discharge port 112 and the discharge space 20 communicate with each other. Then, the compressed fluid is discharged.
If the pressure of the compression work space 19 at the moment of communication is equal to or lower than the pressure of the discharge space 20, the discharge valve 221 has not yet opened, and the orbiting scroll 10 orbits to compress the fluid, The discharge valve 221 opens only when the pressure in 19 becomes higher than the pressure in the discharge space 20. The discharged compressed fluid flows into the closed container through the communication port 131 and is discharged from the discharge pipe 21 to the outside of the closed container 17.

The valve retainer 222 included in the valve device 22 regulates the valve opening height of the discharge valve 221. Further, when the pressure in the compression work space 19 becomes abnormally high during liquid compression, the axial compliance mechanism 23 operates and the orbiting scroll 10 moves to the bearing member 13 side, thereby the fixed scroll. An appropriate gap is formed at the tip of the spiral blade 111 of 11 and the liquid is allowed to escape from there to avoid an abnormal rise in pressure.

A back pressure divider band 24 is provided on the orbiting scroll 10 side of the bearing member, and a discharge pressure is provided on the center side of the back pressure divider band 24 of the orbiting end plate 102 and a suction pressure is provided on the outside. It works, and an appropriate thrust force works during normal operation.

Further, as another embodiment of the present invention, as shown in FIG. 3, the lower discharge valve of the discharge valve 221 has a concave or convex shape with respect to the surface of the fixed scroll on which the discharge valve is fixed. Alternatively, the discharge valve may be shaped so that the vicinity of the tip opposite to the side where the discharge valve is fixed to the fixed scroll has a gap with the fixed scroll in advance.

Further, as shown in FIG. 4, the shape of the discharge port 112 may be such that the portion in contact with the discharge valve 221 is wider than that on the compression work space 19 side. Figure 4 (a)
4B shows the case where the discharge port is tapered, and FIG. 4B shows the case where the spot facing is provided.

[0024]

As is apparent from the above description, the present invention prevents backflow by the discharge valve even if insufficient compression occurs, and energy loss does not occur. Also, due to the cushioning effect between the two discharge valves, and the contact surface between the lower discharge valve and the fixed scroll, and the influence of the compressed fluid and lubricating oil that entered into the respective contact surfaces, a discharge valve with relatively low rigidity is used. Even when the valve is closed, it does not strongly collide with the contact surface of the fixed scroll, and almost no impact noise is generated.
Furthermore, by enlarging the discharge port as compared with the discharge valve side, the discharge process can be performed smoothly while the increase in dead volume is minimized, and discharge loss can be suppressed.

Further, it is possible to provide a scroll compressor which prevents backflow of the discharge fluid, suppresses the noise generated in the discharge valve to be small, and has a small discharge resistance, high efficiency and low noise.

[Brief description of drawings]

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

FIG. 2 is an enlarged sectional view of the valve device section.

FIG. 3 is a sectional view of a valve device of a scroll compressor according to another embodiment of the present invention.

FIG. 4 is a sectional view of a discharge port shape of a scroll compressor according to another embodiment of the present invention.

5A is a cross-sectional view of a valve device in a conventional scroll compressor, and FIG. 5B is a plan view of the valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Orbiting scroll 101 Vortex blade of orbiting scroll 102 Orbiting end plate 11 Fixed scroll 111 Vortex blade of fixed scroll 112 Discharge port 113 Suction port 12 Rotation restraint part 13 Bearing member 14 Spindle 19 Compression work space 20 Discharge space 22 Valve device 221 Discharge valve 222 Valve retainer 223 Bolt for fixing valve device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Morimoto 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Teruyuki Akasawa, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. 72) Inventor Kiyoshi Sano 1006 Kadoma, Kadoma City, Osaka Prefecture, Matsushita Electric Industrial Co., Ltd. (72) Sadao Kawahara, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] 1. A compression mechanism comprising: a fixed scroll having spiral blades; and a orbiting scroll having spiral blades arranged on the orbiting end plate so as to mesh with the fixed scroll to form a plurality of compression work spaces. It is composed of a rotation restraint component for restraining the rotation of the orbiting scroll to cause a orbital motion, and continuously compresses the fluid taken in by the radially outer peripheral portion of the spiral vane in the compression work space toward the center, An elastic plate having one end in the discharge valve longitudinal direction fixed to the fixed scroll so that the compressed fluid is discharged from the discharge port provided near the center of the fixed scroll and the discharge port is opened and closed at the discharge portion. Two discharge valves consisting of are arranged in a stacked manner, and the discharge valve in contact with the fixed scroll of the two discharge valves is connected to the discharge port of the fixed scroll. A scroll compressor having a hole that is the same as or larger than the discharge port in the hitting portion. 2. The discharge valve in contact with the fixed scroll of the two discharge valves has a concave or convex shape or the discharge valve is fixed to the fixed scroll with respect to the surface of the fixed scroll fixing the discharge valve. The scroll compressor according to claim 1, wherein a portion near the tip on the side opposite to the side has a shape having a gap with the fixed scroll in advance. 3. The scroll compressor according to claim 1, wherein a portion of the discharge port in contact with the discharge valve is wider than that on the compression work space side.