JP2880780B2 - Scroll compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to, for example, a scroll type compressor constituting a refrigeration cycle of an air conditioner, and in particular, a stationary part constituting a scroll compression mechanism thereof. The present invention relates to an improvement in a wing shape of a scroll wing and an orbiting scroll wing.

(Prior Art) For example, scroll compressors having extremely low kinetic noise and high compression efficiency as compared with a normal rotary compressor used as a compressor constituting a refrigeration cycle of an air conditioner are frequently used. Tend to be.

This type of scroll compressor is configured, for example, as shown in FIG. That is, 1 is a closed case. A frame 3 is provided in the closed case 1 via a frame support plate 2 so as to partition the inside of the closed case 1 up and down. An electric motor unit 4 is provided on the upper part of the frame 3, and a scroll compression mechanism part 5 is provided on the lower part.

The motor unit 4 includes a stator 6 fitted to the closed case 1 and a rotor 7 provided in the stator 6 with a small gap.

A main shaft 8 is fitted to the rotor 7 along the axis thereof. The main shaft 8 is rotatably supported by the frame 3 and extends to the scroll compression mechanism 5. That is, the scroll compression mechanism 5 and the electric motor 4 are connected to each other via the main shaft 8.

The scroll compression mechanism 5 includes a fixed scroll blade 9 attached to and fixed to the frame 3, and a revolving scroll blade 10 that meshes with the fixed scroll blade 9 so as to be freely rotatable and forms a compression chamber S in a space between each other. It is composed of
The fixed scroll wing 9 includes a head plate portion 9a and the head plate portion 9a.
And a spiral wing 9b standing upright at one end of the wing. And, a flange portion provided integrally with the peripheral edge of the end plate portion 9a
9c is attached and fixed to the frame 3. The orbiting scroll blade 10 includes a mirror plate 10a and a spiral blade 10b provided upright at one end of the mirror plate 10a. The boss 10c integrally projecting from the end plate 10b is connected to the spindle 8
Is slidably engaged with a boss 8a provided integrally with the lower end of the boss 8 and eccentric to the axis.

A balancer 11 is fitted to the boss 8a at the lower end of the main shaft 8, and the frame plate of the frame 3 and the orbiting scroll wing 10
A thrust ring 12 is interposed between the thrust ring 12 and the base 10a. 13 in the figure
Is an Oldham ring for preventing the rotation of the orbiting scroll blade 10 from rotating.

A suction pipe 14 penetrates a lower portion of the closed case 1, and an opening end thereof is exposed from a flange portion 9 c of the fixed scroll blade 9 to an outer peripheral portion of the compression chamber S. Orbiting scroll wing above
A gas discharge passage 15 communicating with the axis of the boss portion 10c of the ten and the axis of the main shaft 8 is provided. The gas discharge passage 15 of the main shaft 8 opens at the upper end of the main shaft 8 into the closed casing 1, and a discharge pipe (not shown) is provided at the upper end of the closed case 1.

In the scroll compressor configured as described above, the electric motor unit 4 is energized to drive the scroll compression mechanism unit 5. That is, when the orbiting scroll blade 10 is caused to orbit with respect to the fixed scroll blade 9, a low-pressure refrigerant gas, for example, a fluid to be compressed, is sucked into the compression chamber S from the suction pipe 14 and compressed. When the compression chamber S gradually contracts and moves to the center, it rises to a predetermined pressure. The refrigerant gas is discharged into the discharge gas passage 15 and once discharged into the closed case 1, and then guided to a predetermined external device via a discharge pipe. The electric motor unit 4 is controlled to an optimal operation frequency according to the load, and air conditioning can be performed under optimal conditions.

(Problems to be Solved by the Invention) By the way, the wing portion 10 of the conventional orbiting scroll wing 10 is described.
FIG. 8 shows a cross-sectional shape of b, and FIG. 9 shows a cross-sectional shape of the wing portion 9b of the fixed scroll wing 9. The respective wings 10b and 9b are respectively wound from the winding start end O to the winding end end.
To O _b, with the thickness of all uniform, it is bent along the involute curve of the reference.

FIG. 10 shows a compression process in the scroll compression mechanism 5 including the orbiting scroll blade 10 and the fixed scroll blade 9. That is, the horizontal axis represents the rotation angle θ (DEG) of the main shaft 8, and the vertical axis represents the pressure P (kg / cm) of the compression chamber S.
² · G), and the compression ratio is taken along part of the vertical axis. The different change curves are the number of turns N of the wing portions 10b and 9b.

As is apparent from the figure, in any number of turns N, the compression process is performed only by the number of turns N of the blade portions 10b and 9b and the rotation angle θ of the main shaft 8 after the refrigerant is closed in the compression chamber S. It will be decided. Therefore, there is a disadvantage that the pressure of the fluid to be compressed in the compression chamber S rises more than necessary and a higher compression ratio cannot be obtained.

Further, each of the wings 10b, 9b are all from the winding start end portion O until the winding end portion O _b that is the thickness of the uniform is as previously described. On the other hand, in the compression chamber S, the pressure increases from the outer peripheral portions of the wing portions 10b and 9b toward the central portion, and the pressure is the highest in the central portion. That is, the wings
Despite the differences in the pressures received over the entire lengths of 10b and 9b, the plate thickness is uniform, so that the reliability of the strength particularly at the center of the wings 10b and 9b is low.

The present invention has been made in view of the above circumstances, and an object of the present invention is to change the thickness of each fixed wing and the orbiting scroll wing to an ideal state, and to obtain the compressed state in the compression chamber. An object of the present invention is to provide a scroll-type compressor that hastens the pressure rise of a fluid, improves compression efficiency with a higher compression ratio, and at the same time, increases strength and reliability at the center of the wing part. .

[Structure of the Invention] (Means and Action for Solving the Problems) That is, the present invention relates to a fixed scroll wing in which a spiral wing is erected at one end of a head plate, and one end of the head plate. Orbiting scroll wings, each of which has a swirling wing portion standing upright, are rotatably meshed with each other, and a compressed chamber formed therebetween compresses and discharges a fluid to be compressed. Each of the wings of the scroll wing and the orbiting scroll wing has a curved inner wall surface at which the winding end angle of the wing is φ.
_{From 0} to the angle (φ ₀ -2π), the outer wall curved surface is formed as a reference involute curve from the winding end angle φ ₀ to the angle (φ ₀ -3π) of the wing, and the angle of the inner wall curved surface (φ
₀ ) -2π) to the winding start angle 0, and from the angle of the outer wall curved surface (φ ₀ −3π) to the winding start angle 0, K (mm / mm) This is a scroll-type compressor characterized in that curves are shifted inward by 2π: reduction coefficient).

In such a scroll compressor, the central portion of the wing portion receives a stronger pressure than the outer peripheral portion during the compression action. However, the wing portion has a large thickness from the middle to the center, and both the inner wall curved surface and the outer wall curved surface have ideal shapes, so that the compression speed is increased, and a high compression ratio can be obtained.
The strength of the wing itself increases.

(Embodiment) Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Except for the orbiting scroll wing and the fixed scroll wing, each of which will be described later with reference to FIG. Since a type compressor can be applied, a new description is omitted here.

FIG. 1 shows the cross-sectional shape of the wing portion 10B of the orbiting scroll wing, and FIG. 2 shows the wing portion 9B of the fixed scroll wing.
The cross-sectional shape is shown. The cross-sectional shapes of these wing portions 10B and 9B are the same as the conventional one in that they are symmetrical in the left-right direction and have the same shape as each other.

As the actual cross-sectional shape, in the wing portion 10B of the orbiting scroll wing shown in FIG. 1, the inner wall curved surface m extends from the winding end angle φ ₀ which is the winding end end to the winding start angle 0 which is the winding start end. Both the outer surface curved surface n and the outer wall curved surface n do not change up to a predetermined intermediate portion, but change thereafter. That is, the winding end angle φ _{0 at} the inner wall curved surface m of the wing portion 10B.
To the angle (φ ₀ -2π) is a curved surface along the same reference involute curve as in the prior art. This angle (φ ₀ −
From 2π) to the winding start angle 0, K (mm) is larger than the reference involute curve in proportion to the winding angle φ of the wing 10B.
A modified involute curve, which is a curve shifted inward by / 2π: reduction coefficient). In addition, the outer wall curved surface n
Is a curved surface along the reference involute curve similar to the conventional one from the winding end angle φ ₀ to the angle (φ ₀ −3π) of the wing portion 10B. From this angle (φ ₀ -3π), the winding start angle 0
Up to this point, a modified involute curve is formed which is shifted inward by K (mm / 2π: reduction coefficient) from the reference involute curve in proportion to the winding angle φ of the wing portion 10B.

In the wing portion 9B of the fixed scroll wing shown in FIG.
From the winding end angle φ ₀ of the inner curved surface m to the angle (φ ₀ -2
up to π) is a curved surface along the same standard involute curve as in the past, and from this angle (φ ₀ -2π) to the winding start angle 0 is proportional to the winding angle φ of the wing 9B and is smaller than the standard involute curve. It is formed as a deformed involute curve, which is a curve shifted inward by K (mm / 2π: reduction coefficient). The outer wall curved surface n is a curved surface along the same standard involute curve as the conventional one from the winding end angle φ ₀ to the angle (φ ₀ −3π) of the wing portion 9B, and the winding start angle 0 from this angle (φ ₀ −3π). Up to the wing) in proportion to the winding angle φ of 9B,
It is formed as a modified involute curve, which is a curve shifted inward by K (mm / 2π: reduction coefficient) from the reference involute curve. Note that K (mm / 2π) is a proportional constant that determines the rate of involute curve reduction.
(K> 0) FIG. 3 is a solid line X showing the change of the plate thickness with respect to the involute winding angle φ in the wing portions 10B and 9B of the orbiting scroll wing and the fixed scroll wing thus formed. A dashed line Y indicates a plate thickness based on a conventional reference involute curve.

The thickness T 'based on the conventional involute curve is 2a
α (a is the base circle radius, α is the involute start angle) and does not change over its entire length.

On the other hand, the thickness change X of the new wing portion is φ ₀ −2
in the range of π ≦ φ ≦ φ _0, a plate thickness of T = T '= 2aα, is identical to that of the prior art.

T in the range of _{φ 0 -3π ≦ φ ≦ φ 0} -2π = T '+ K / 2π
{(Φ ₀ * 2π) −φ}.

In the range of φ ≦ φ ₀ −3π, the plate thickness is T = T ′ + 2K.

Thus, the orbiting scroll blades and the wing portions 10B and 9B of the fixed scroll blades mesh with each other to perform a compression operation. At the moment when the outermost compression chamber traps the non-compressed gas, that is, when the rotation angle θ of the main shaft 8 is 0, the compression chamber is formed only by the conventional involute curve. Excluded volume is obtained by the same volume as 10b and 9b.

Then, when the main shaft 8 rotates and the outermost compression chamber gradually moves inward to θ degrees, a compression state as shown in FIG. 5 is established. That is, at least a portion of the compression chamber S _1, though suffering from the deformation involute newly set, the displacement volume is smaller than the displacement volume of the compression chamber formed by an involute curve of a conventional reference .

FIG. 6 shows a compressed state at the same angle (θ degrees) at the wing portions 10b and 9b formed by a conventional reference involute curve. Its displacement volume is greater than the displacement volume of the compression chamber S ₁ formed with a new variant involute curve.

Position where the compression chamber S ₁ is opposed to the discharge gas passage 15,
That is, this state continues up to the position of the winding start angle 0. As a result, towards the compression chamber S ₁ is formed with a deformation involute curve shown in FIG. 5 is a pressure rise rate than the compression chamber S ₁ 'which is formed in an involute curve of a conventional reference increase. The rate of increase in pressure is the pressure speed, and the faster the pressure speed, the higher the compression ratio. The pressure of the compression chamber S _1, each wing portion 10b, but gradually high pressure over the central portion from the outer peripheral portion of 9b, towards the center than the outer peripheral portion wings 10b, and thickness of 9b , The strength is increased and the reliability is improved.

FIG. 4 shows, as an example, a calculation result of the pressure rise process of the compression chamber S with respect to the rotation angle θ of the main shaft 8 when the number of turns of the wing portions 10b and 9b is four. The parameter K in the figure is a dimensionless reduction coefficient obtained by dividing the reduction coefficient K by the turning pitch P, and K = 0 is the case of a conventional involute blade. Therefore, as the dimensionless reduction coefficient K is increased as in the present invention, the compression speed is increased and higher compression can be achieved.

[Effects of the Invention] As described above, according to the present invention, the wings of each of the fixed scroll wing and the orbiting scroll wing have their inner wall curved surfaces formed from the winding end angle φ ₀ of the wings by an angle (φ ₀ -2).
π), and the outer wall curved surface is wound at the winding end angle φ ₀
To an angle (φ ₀ −3π) from the angle of the inner wall curved surface (φ ₀ −2π) to the winding start angle, and an angle (φ ₀ −3π) of the outer wall curved surface.
From the winding start angle to the winding angle of the wing is proportional to the winding angle of the wing, and K (mm / 2π: reduction factor) from the standard involute curve
However, since the curves are shifted inward only, the compression speed can be increased without changing the outer diameter and the height of the wing portion, and the effect that the compression efficiency can be improved by the high compression ratio can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional plan view of a wing portion of an orbiting scroll wing showing one embodiment of the present invention, FIG. 2 is a cross-sectional plan view of a wing portion of a fixed scroll wing, and FIG. FIG. 4 is a characteristic change diagram of a dimensionless reduction coefficient, FIG. 5 is a diagram showing a compression chamber shape during compression, FIG. 6 is a diagram showing a compression chamber shape during compression in a conventional example of the present invention, FIG. FIG. 7 is a longitudinal sectional view of a scroll type compressor with a part omitted, FIG. 8 is a cross-sectional plan view of a wing portion of an orbiting scroll blade showing a conventional example of the present invention, and FIG. FIG. 10 is a plan view and FIG. 10 is a characteristic diagram of a compression process at different numbers of turns of the wing. 9a ... end plate part, 9B ... wing part, 9 ... fixed scroll wing, 10a ...
End plate, 10B: wing, 10: orbiting scroll wing, S: compression chamber, m: curved inner wall, n: curved outer wall.

Claims (1)

(57) [Claims] 1. A fixed scroll wing comprising a head plate portion and a spiral wing portion erected at one end of the head plate portion,
A revolving scroll blade composed of a head plate portion and a spiral wing portion provided upright at one end of the head plate portion is rotatably meshed with each other, and a fluid to be compressed is sucked into a compression chamber formed therebetween, and compressed. In the scroll-type compressor that discharges the fixed scroll blades and the orbiting scroll blades, the wings of the fixed scroll wings and the orbiting scroll wings have their inner wall curved surfaces extending from the winding end angle φ ₀ to the angle (φ ₀ -2π) and the outer wall curved surfaces. From the winding end angle φ ₀ to the angle (φ ₀ -3π) of the wing portion, is formed as a reference involute curve, and the angle (φ ₀ ) -2 of the inner wall curved surface is obtained.
π) to the winding start angle 0, and from the angle of the outer wall curved surface (φ ₀ -3π) to the winding start angle 0, K (mm) from the standard involute curve in proportion to the winding angle φ of the wing.
/ 2π: reduction coefficient).