JPH09296786A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll compressor, which is provided with higher performance and lowers noise and vibration, by means of a simple means by reducing discharge resistance of compressed refrigerant gas, reducing reexpansion of the refrigerant gas during overcompression, and matching discharge timing of paired compression chambers so as to reduce a compression loss. SOLUTION: The subject compressor is provided with a fixed scroll 3 and a rotary scroll 4, whose scroll laps 3b, 4b on end plates 3a, 4a are geared to each other so as to form a compression chamber 5, a crank shaft 6, a frame 7 provided with a bearing 8 rotating the crank shaft 6, and a rotation preventing means for the rotary scroll 4. A recessed part arranged in the vicinity of the scroll center of the rotary scroll 4 is formed into a cone type recess part 41, whose diameter is reduced toward the depth side, or a sphere type recess part 41. A discharge port 3c arranged in the fixed scroll 3 is provided with a diameter larger than that of the cone type recess part 41 arranged in the rotary scroll 4.

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 more particularly to a scroll compressor suitable for improving reliability and efficiency with simple means, such as an air conditioner and a refrigerator. Used for.

[0002]

2. Description of the Related Art The overall structure of a conventional scroll compressor and the structure of the digging of an orbiting scroll will be described with reference to FIGS. 9 is a vertical sectional view of a conventional scroll compressor, FIG. 10 is a sectional view of an orbiting scroll of a conventional scroll compressor, and FIG. 11 is a sectional view of another orbiting scroll of a conventional scroll compressor. is there.

The conventional scroll compressor shown in FIG. 9 has a compression mechanism 2 and an electric motor 10 housed in a hermetically sealed case 1, and a fixed scroll 3 has a spiral wrap 3b on an end plate 3a. Is upright, and the orbiting scroll 4
Is a spiral wrap 4b standing upright on the end plate 4a, and the compression chamber 5 is formed by meshing the wraps inward.

In the compression chamber 5, the refrigerant gas sucked from the suction pipe 20 is directed toward the center while gradually reducing its volume due to the oscillating rotation of the orbiting scroll 4, and the compressed refrigerant gas is transferred to the orbiting scroll 4. The central discharge port 3 is provided through a cylindrical recess 4d (see FIG. 10) provided near the center.
Discharge from c into the closed case 1. The compressed refrigerant gas is sent out from the discharge pipe 21 to the refrigeration cycle pipe outside the machine.

The electric motor 10 includes a stator 11 and a rotor 12.
It is composed of 6 is a crankshaft that transmits the rotational force of the electric motor 10 to revolve the orbiting scroll 4, and 7 is
A frame provided with a main bearing 8 for rotating the crankshaft 6, and a sub-bearing 9 provided in a fixed bearing housing 13. Crankshaft 6 coupled to rotor 12
Is a main bearing 8 and a sub bearing 9 provided on both sides of the electric motor 10.
The sub-bearing 9 is a spherical bearing capable of self-alignment.

As shown in FIG. 10, the end plate 4a near the center of the spiral of the orbiting scroll 4 is provided with a cylindrical recess 4d for the dug portion. Further, in another conventional example, there is one in which the cylindrical recess 4d is not formed. Furthermore, the hole diameter of the discharge port 3c for discharging the compressed refrigerant gas provided in the fixed scroll 3 is substantially the same as that of the cylindrical recess 4d provided in the orbiting scroll 4. Regarding the dug shape, in addition to the cylindrical shape as shown in FIG.
As described in Japanese Patent Publication No. 90, there is an example of a recess 4e having a trapezoidal cross section as shown in FIG.

[0007]

In the compressor structure of the prior art described above, since the cylindrical concave portion provided near the spiral center of the swirl scroll has a square, rectangular or trapezoidal cross-section, the compression is reduced. When the generated refrigerant gas is discharged from the discharge port 3c, the flow of the refrigerant is not smooth at the corners of the recess, and the flow path resistance increases, which is a factor that deteriorates the performance. Further, the cylindrical recess having a square or rectangular cross section becomes a dead volume that is not compressed during the gas compression process, which is a factor that deteriorates the performance.

Further, in consideration of workability, the cylindrical recess provided near the center of the spiral of the orbiting scroll has a problem that the recessed surface and the bottom surface of the orbiting scroll are at a right angle and burrs are likely to occur. Further, since the recess is provided in the vicinity of the center of the spiral, the upright spiral wrap obstructs the field of view, and it is difficult for the naked eye to see the burr, which makes the deburring work difficult.

Further, when there is no recess near the center of the orbiting scroll as in another conventional example, there is an advantage that the dead volume is small, but immediately after the two opposed compression chambers form the minimum closed space. , When discharging from the discharge port, the passage areas communicating with the two compression chambers and the opening chamber do not become the same, the discharge timing is shifted, the orbiting scroll is swung in the axial direction, and the wrap tip between the orbiting and fixed scrolls is There is a problem that the clearance of the sliding part between the tooth bottom and the tooth bottom is increased, and the compressed refrigerant gas leaks from that part, which deteriorates the performance and increases the vibration and noise.

Further, conventionally, the diameter of the discharge port provided in the fixed scroll and the inner diameter of the cylindrical recess provided in the orbiting scroll are substantially the same, but in view of improving the performance, the diameter of the discharge port is made as large as possible to make the orbiting scroll. The recess provided in
Since it becomes a dead volume that cannot be compressed, it is desirable to make it as small as possible and there is a problem that the performance is slightly inferior.

The present invention has been made to solve the above-mentioned problems of the prior art. The object of the present invention is to smooth the flow of compressed refrigerant gas, reduce discharge resistance, and prevent overcompression. Re-expansion of the refrigerant gas is reduced, the compression loss is reduced by adjusting the discharge timing of the paired compression chambers, performance is improved, noise and vibration are prevented, and a recess provided in the center of the orbiting scroll is used. It has a shape that does not easily generate burrs and has good workability.
It is to provide a scroll compressor with low vibration.

[0012]

In order to achieve the above object, the structure of a scroll compressor according to the present invention is such that an electric motor and a compression mechanism portion connected to the electric motor are housed in a closed container. Then, the compression mechanism portion has a spiral wrap on each end plate, fixed scroll and orbiting scroll that meshes each wrap to form a compression chamber, and rotation preventing means of the orbiting scroll, The fixed scroll includes a crank shaft that transmits the rotational force of the electric motor to give a turning motion to the orbiting scroll, and a frame that includes a bearing that rotates the crank shaft, and the fixed scroll has a discharge port for discharging compressed refrigerant gas. A scroll compressor provided with a dug leading to the compression chamber near the center of the spiral on the end plate of the orbiting scroll, wherein the orbiting scroll The cross-sectional shape of digging, in which the rear side of the dug the has a substantially conical or Ryakudama shape whose diameter. Further, the discharge port provided in the fixed scroll has a diameter larger than the diameter of the recess provided in the orbiting scroll.

[0013]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIG. First Embodiment FIG. 1 shows a first embodiment of the present invention.
This will be described with reference to 2, 3, 6, and 7. 1 is a vertical cross-sectional view of a scroll compressor in which a conical recess is provided near the center of a spiral of an orbiting scroll according to an embodiment of the present invention.
1 is a sectional view of an orbiting scroll of the scroll compressor of FIG. 1, FIG. 3 is a plan view of FIG. 2, FIG. 6 is a sectional perspective view of a compression mechanism portion of a scroll compressor to which the present invention is applied, and 7 is a book It is an explanatory view showing a compression principle of a scroll compressor to which the invention is applied. In the figure, the same reference numerals as those in FIG. 9 indicate the same or corresponding portions as those in the conventional technique.

In FIG. 1, 1 is a closed case, 2 is a compression mechanism portion housed in the upper part of the closed case 1, 3 is a fixed scroll in which a spiral wrap 3b is upright on an end plate 3a, and 4 is a fixed scroll. , A orbiting scroll in which a spiral wrap 4b stands upright on an end plate 4a, and the fixed scroll 3 and the orbiting scroll 4 form a compression chamber 5 by engaging the respective wraps 3b and 4b inward. ing.

In the compression chamber 5, the refrigerant gas sucked through the suction pipe 20 and the suction port 30 (see FIG. 6) is orbited to the orbiting scroll 4.
The volume of the refrigerant gas gradually decreases toward the center by oscillating rotation, and the compressed refrigerant gas is sealed from the central discharge port 3c through the conical recess 41 provided near the central part of the orbiting scroll 4. It is what is discharged into 1. The compressed refrigerant gas is sent out from the discharge pipe 21 to the refrigeration cycle pipe outside the machine.

Reference numeral 6 is a crankshaft, and its eccentric portion 6a (eccentricity ε) is fitted into the boss portion of the orbiting scroll 4, and the rotational force of the electric motor 10 is transmitted to revolve the orbiting scroll 4. The orbiting scroll 4 is the Oldham ring 15.
Rotation is prevented by the action (see FIG. 6). 7 is a fixed frame that houses the orbiting scroll 4 and fastens the fixed scroll 3 with bolts 16 at the periphery, 8 is a main bearing that is provided on the frame 7 and rotatably supports the crankshaft 6, and 9 is A sub-bearing, which is located on the side opposite to the electric motor with respect to the main bearing 8, is a bearing housing of the sub-bearing 9.

The electric motor 10 includes a stator 11 and a rotor 12
And the crankshaft 6 connected to the rotor 12 is
It is configured to be supported by a main bearing 8 and a sub bearing 9 provided on both sides of the electric motor 10. The main bearing 8 is a plain sliding bearing having a general inner diameter surface, and the sub bearing 9
Is a slide bearing whose inner diameter surface is self-aligning (generally spherical).

As described above, the general structure of the scroll compressor is that the electric motor 10 and the electric motor 10 are provided in the closed case 1.
And a compression mechanism portion 2 connected to
The compression mechanism portion 2 has spiral wraps 3b and 4b on the end plates 3a and 4a, respectively.
b and 4b mesh with each other to form a compression chamber 5, a fixed scroll 3 and an orbiting scroll 4, an Oldham ring 15 related to a rotation preventing means of the orbiting scroll 4, and a rotational force of an electric motor 10 are transmitted to the orbiting scroll 4. It is provided with a crankshaft 6 for giving a motion and a frame 7 having a main bearing 8 for rotating the crankshaft 6.

Next, the basic structure and principle of the scroll compressor will be described with reference to FIGS. FIG. 6 shows the basic structure of the compressor mechanism, and the refrigerant gas is the spiral wraps 3 b and 4 b of the fixed scroll 3 and the orbiting scroll 4.
And the end plates 3a holding the spiral wraps 3b, 4b,
It is compressed in the space formed between 4a.

The fixed scroll 3 has a suction port 3 on its outer peripheral portion.
0, the end plate 3a has a discharge port 3c at the center thereof, and the outer peripheral portion thereof is fixed to the frame 7 which is a stationary component. The orbiting scroll 4 performs an orbiting motion (revolution) with the amount of eccentricity as the orbiting radius as the crankshaft 6 rotates. This movement is a movement in which the orbiting scroll 4 is rotated around its center around the center of the fixed scroll while keeping its posture constant without rotating. The Oldham ring 15 is a component that prevents the orbiting scroll 4 from rotating, and the projection on the upper surface is incorporated in the key groove on the rear surface of the orbiting scroll, and the projection on the lower surface is incorporated in the key groove on the frame 7.

Next, the compression principle will be described with reference to FIG. The spiral wraps 3b and 4b of the fixed scroll 3 and the orbiting scroll 4 have basically the same mirror-symmetrical shape, and the phases are 180 ° out of phase, and the centers of the respective spirals are the orbiting radius (the amount of eccentricity). ) Combined in a separated state. As a result, the two wraps 3 shown in black and white in FIG.
b and 4b contact (approximate) at multiple points and both laps 3b and 4b
A plurality of compression chambers 5 are formed between them.

In FIG. 7, the upper left diagram (a) is the wraps 3b, 4
b shows the suction completion state in which the compression chamber 5 on the outer peripheral portion is closed,
The state when the center of the orbiting scroll 4 makes a circular orbital motion in the clockwise direction is rotated every 90 ° (b), (c), (d).
Is shown in As a result, the compression chamber 5 becomes the wrap 3b,
It is a compression mechanism that moves while reducing the volume toward the center of 4b.

Next, the features of the present invention will be described. As shown in FIG. 2, the orbiting scroll 4 includes a wrap 4
A conical recess 41, which is a dug-up, is formed on the end plate 4a near the center of b. The conical recess 41 is formed in a substantially conical shape having a small diameter on the deep side of the dug. It is desirable that the conical shape be a spherical shape having a large radius as much as possible in the apex angle portion and processed so as not to become a corner portion.

The refrigerant gas to be compressed is passed through the conical recess 4
By making it flow along the tapered portion of No. 1, the discharge resistance is reduced, the re-expansion of the refrigerant gas at the time of overcompression is reduced, and as shown in 5-1 and 5-2 in FIG. The discharge timing of the compression chamber 5 (collectively referred to as 5-1 and 5-2) can be adjusted to reduce compression loss, improve performance, and prevent noise and vibration. Further, the conical concave portion 41 provided near the central portion of the orbiting scroll 4 can be formed into a shape in which burrs are less likely to occur, and good workability can be achieved. A scroll compressor with low vibration can be provided.

[Second Embodiment] FIG. 4 is a sectional view of an orbiting scroll showing another embodiment of the present invention, and FIG. 5 is a plan view of FIG. The dug portion shown in FIG. 4 is a substantially spherical recess 42 having a small diameter on the inner side of the dug portion.
Even if the concave portion is not a conical shape but a spherical shape, the same effect as that of the previous embodiment can be obtained. This is because the concave portion having a conical shape or a spherical shape has a smaller number of corner portions and the occurrence of turbulence or the like can be suppressed as compared with a square, rectangular, or trapezoidal cross section, so that the flow path resistance can be reduced.

[Third Embodiment] FIG. 8 is a sectional view of a compression mechanism portion showing still another embodiment of the present invention. In the compression mechanism portion shown in FIG. 8, the discharge port 3c provided in the fixed scroll 3 is the end plate 4a of the orbiting scroll 4.
The diameter is larger than the diameter of the conical recess 41 provided near the center of the upper spiral. As a result, the discharge resistance when discharging gas can be reduced, the dead volume that cannot be compressed can be minimized, and the re-expansion at the time of overcompression can also be reduced.
It is possible to provide a scroll compressor with low noise and low vibration.

In the above-described embodiment, the orbital scroll has a cross-sectional shape of the digging that is a substantially conical shape or a substantially spherical shape in which the deep side of the digging has a small diameter. In addition to this example, The example in which the diameter of the discharge port provided in the fixed scroll is made larger than the diameter of the dug portion provided has been described. The diameter of the discharge port provided in the fixed scroll is larger than the diameter of the digging part provided in the orbiting scroll for the conventional cylindrical recess whose cross-sectional shape of the orbiting scroll is square, rectangular or trapezoidal. Even in this case, the discharge resistance at the time of discharging the gas can be reduced accordingly, and the effect is expected.

[0028]

As described in detail above, according to the present invention, the flow of the compressed refrigerant gas is made smooth, the discharge resistance is reduced, the re-expansion of the refrigerant gas at the time of over-compression is reduced, and The compression loss is reduced by adjusting the discharge timing of the compression chamber, which improves the performance, prevents the generation of noise and vibration, and makes the recess in the center of the orbiting scroll less prone to burrs to improve workability. It is possible to provide a scroll compressor which can be made favorable and which is inexpensive and has high performance, low noise and low vibration by a simple means.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a scroll compressor in which a conical recess is provided near the center of a spiral of an orbiting scroll according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of an orbiting scroll of the scroll compressor of FIG.

FIG. 3 is a plan view of FIG. 2;

FIG. 4 is a cross-sectional view of an orbiting scroll showing another embodiment of the present invention.

FIG. 5 is a plan view of FIG.

FIG. 6 is a sectional perspective view of a compression mechanism portion of a scroll compressor to which the present invention is applied.

FIG. 7 is an explanatory diagram showing a compression principle of a scroll compressor to which the present invention is applied.

FIG. 8 is a cross-sectional view of a compression mechanism portion showing still another embodiment of the present invention.

FIG. 9 is a vertical cross-sectional view of a conventional scroll compressor.

FIG. 10 is a cross-sectional view of an orbiting scroll of a conventional scroll compressor.

FIG. 11 is a cross-sectional view of another orbiting scroll of the conventional scroll compressor.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Sealed case, 2 ... Compression mechanism part, 3 ... Fixed scroll, 4 ... Orbiting scroll, 3a, 4a ... End plate, 3b, 4
b ... Wrap, 3c ... Discharge port, 5 ... Compression chamber, 6 ... Crank shaft, 7 ... Frame, 8 ... Main bearing, 9 ... Sub bearing, 10 ... Electric motor, 11 ... Stator, 12 ... Rotor, 41 ... Conical recess , 42 ... Spherical recess.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tatsuya Wakana 2 709 Tomita, Ohira-cho, Shimotsuga-gun, Tochigi Prefecture 2 Hitachi Tochigi Electronics Co., Ltd.

Claims (3)

[Claims] 1. A hermetically-sealed container for accommodating an electric motor and a compression mechanism portion connected to the electric motor, wherein the compression mechanism portion has a spiral wrap on each end plate, A fixed scroll and an orbiting scroll that form a compression chamber by meshing the wraps, a rotation preventing means of the orbiting scroll, a crankshaft that transmits the rotational force of the electric motor to give an orbiting motion to the orbiting scroll, and the crankshaft is rotated. And a frame having a bearing for allowing the fixed scroll to have a discharge port for discharging compressed refrigerant gas, and a digging leading to the compression chamber near the center of the spiral on the end plate of the orbiting scroll. In a scroll compressor provided, the cross-sectional shape of the digging of the orbiting scroll has a substantially conical shape or a substantially spherical shape in which the deep side of the digging has a small diameter. A scroll compressor characterized by the above. 2. A hermetically-sealed container for accommodating an electric motor and a compression mechanism portion connected to the electric motor, wherein the compression mechanism portion has a spiral wrap on each end plate, A fixed scroll and an orbiting scroll that form a compression chamber by meshing the wraps, a rotation preventing means of the orbiting scroll, a crankshaft that transmits the rotational force of the electric motor to give an orbiting motion to the orbiting scroll, and the crankshaft is rotated. And a frame having a bearing for allowing the fixed scroll to have a discharge port for discharging compressed refrigerant gas, and a digging leading to the compression chamber near the center of the spiral on the end plate of the orbiting scroll. In the scroll compressor provided, the diameter of the discharge port provided in the fixed scroll is made larger than the diameter of the dug portion provided in the orbiting scroll. Scroll compressor characterized by. 3. A hermetically-sealed container for accommodating an electric motor and a compression mechanism portion connected to the electric motor, wherein the compression mechanism portion has spiral wraps on respective end plates, A fixed scroll and an orbiting scroll that form a compression chamber by meshing the wraps, a rotation preventing means of the orbiting scroll, a crankshaft that transmits the rotational force of the electric motor to give an orbiting motion to the orbiting scroll, and the crankshaft is rotated. And a frame having a bearing for allowing the fixed scroll to have a discharge port for discharging compressed refrigerant gas, and a digging leading to the compression chamber near the center of the spiral on the end plate of the orbiting scroll. In a scroll compressor provided, the cross-sectional shape of the digging of the orbiting scroll has a substantially conical shape or a substantially spherical shape in which the deep side of the digging has a small diameter. In addition, the scroll compressor is characterized in that the diameter of the discharge port provided in the fixed scroll is made larger than the diameter of the dug portion provided in the orbiting scroll.