JPH0719187A - Scroll fluid machine - Google Patents

Abstract

PURPOSE:To aim at high performance even in the case of the thermal expansion coefficients of two scroll laps being different in a turning or rotating type scroll fluid machine. CONSTITUTION:A gap between the tooth bottom of a scroll lap 2b and the tooth tip of a scroll lap 3b, and a gap between the tooth tip of the scroll lap 2b and the tooth bottom of the scroll lap 3b at the time of scroll members 2, 3 being meshed with each other during the stop of operation is placed in such dimensional relation that the latter is made larger than the former in the case of the thermal expansion coefficient of the scroll lap 2b being larger than that of the scroll lap 3b, that the latter is made smaller than the former in the case of the thermal expansion coefficient of the scroll lap 2b being smaller than that of the scroll lap 3b and that the former and the latter are made the same in the case of the thermal expansion coefficients of both scroll laps being the same.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a revolving scroll fluid machine in which one scroll member is fixed and the other one does not rotate, and two scroll members have a geometric center of a scroll wrap. The present invention relates to a rotary scroll fluid machine that is displaced from each other and both rotate about the respective geometric centers in the same direction and at the same speed.

[0002]

2. Description of the Related Art Conventionally, a scroll fluid machine has been designed to avoid contact between scroll tip and root of a scroll wrap and increase in clearance caused by thermal deformation caused by gas pressure and temperature change during operation. As described in Japanese Patent No. 67902, a gap having a larger central portion than the outer peripheral portion was previously provided between the tooth tip and the tooth bottom. Further, when the two scroll members are different, it is necessary to set the gap between the tip and the root of the scroll wrap in consideration of the difference in material, as described in JP-A-2-16385. Was shown.

[0003]

In the above-mentioned prior art, when the thermal expansion coefficients of the two scroll wraps are different from each other, the gaps set at the tooth tops and the tooth bottoms of the two scroll wraps have the first scroll. It was not taken into consideration that the gap between the root of the tooth and the tip of the second scroll differs from the gap between the tip of the first scroll and the root of the second scroll. As a result, during operation, there is a problem that the gap between the tooth top and the tooth bottom of one scroll wrap increases, internal leakage increases, and friction loss due to contact between the tooth tip and tooth root causes the compressor performance to deteriorate. It was

An object of the present invention is to solve these problems.

[0005]

In order to achieve the above object, a first reference point which defines a distance between both scroll members in a wrap upright direction during operation by a part of the first scroll member or a member which moves integrally with the first scroll member. And a part of the second scroll member or a member that moves integrally with the second scroll member, and has a second reference point that regulates the distance between both scroll members in the wrap upright direction during operation, and both scrolls according to the first and second reference points during assembly. When the inter-member distance is in the specified state, gaps are provided between the tooth tops of the first scroll wrap and the tooth tops of the second scroll wrap, and between the tooth tops of the first scroll wrap and the tooth bottoms of the second scroll wrap, and the magnitude relation between them is provided. The coefficient of thermal expansion of the first scroll wrap at a temperature near the scroll wrap during compressor operation is the thermal expansion at the temperature of the second scroll wrap. If the ratio is larger than the ratio, the latter gap is made larger than the former gap at the position of approximately the same distance in the radial direction from the center of the spiral of each scroll wrap, and the first scroll wrap at the temperature near the scroll wrap during compressor operation is set. When the coefficient of thermal expansion is smaller than the coefficient of thermal expansion at the temperature of the second scroll wrap, the latter gap is made smaller than the former gap at the position at the same distance in the radial direction from the center of the spiral of each scroll wrap, and the compressor operation is performed. When the coefficient of thermal expansion of the first scroll wrap at the temperature near the scroll wrap and the coefficient of thermal expansion of the second scroll wrap at this temperature are approximately the same, the position of approximately the same distance in the radial direction from the center of the spiral of each scroll wrap. In the above, the former gap and the latter gap are substantially the same.

[0006]

During operation of the scroll fluid machine, the first and second scroll members are subject to pressure deformation due to the pressure of the compressible fluid targeted by the scroll fluid machine, and heat generation of the compressible fluid and heat of the motor or the like. Undergoes thermal deformation.
Therefore, when assembling the fluid machine, the gap between the tooth bottom of the first scroll wrap and the tip of the second scroll wrap and the If the gap between the addendum of one scroll wrap and the addendum of the second scroll wrap is made small, the scroll member will be deformed during operation, and the gap between the addendum of the first scroll wrap and the addendum of the second scroll wrap will be reduced. Or the gap between the tip of the first scroll wrap and the bottom of the second scroll wrap causes friction loss, and depending on the structure of the fluid machine, the contact causes the scroll member to move in the upright direction of the wrap. As a result, the distance between the two scroll members increases and the gap expands over a wide range between the tooth tops and bottoms, increasing internal leakage of the target compressible fluid. Performance decreases. For this reason, the difference between the tooth bottom displacement of the first scroll wrap and the tooth tip displacement of the second scroll wrap during the fluid machine operation is previously calculated between the tooth bottom of the first scroll wrap and the tooth tip of the second scroll wrap during assembly. Similarly, the difference between the tooth tip displacement of the first scroll wrap and the tooth root displacement of the second scroll wrap is set in advance as a gap between the tooth tips of the first scroll wrap and the tooth bottom of the second scroll wrap. By setting as above, both gaps during operation become almost 0 over the entire area, almost no contact occurs, friction loss is reduced, and internal leakage of the target compressible fluid can be suppressed. As a result, the performance of the fluid machine is improved. Can be improved. This measure for improving the performance of the scroll fluid machine has little effect unless the two types of gaps are properly set. Therefore, the difference between the tooth tip displacement of the second scroll wrap during operation and the tooth bottom displacement of the first scroll wrap (hereinafter referred to as the A displacement difference), and the tooth bottom displacement of the second scroll lap during operation and the first It is necessary to know the relationship with the difference between the tooth top displacement of the scroll wrap (hereinafter referred to as the B displacement difference).

To know the difference between the A and B displacements, it is necessary to know the displacements of the tip and the bottom of the scroll wrap during operation. These displacements will be considered separately for pressure deformation and thermal deformation with reference to FIGS. The broken line schematically shows the shape before deformation, and the solid line shows the shape after deformation. The symbols in the figure indicate the amount of displacement with the positive direction of the Z axis as the positive direction, D indicates the displacement of the tooth tip, and d indicates the displacement of the tooth bottom. Also, D
(R) added after and d indicates that the displacement amount is a function of the distance r from the scroll center. The subscripts indicate the first subscript: 1 ... first scroll, 2 ... second scroll, second subscript: a ... pressure displacement, b ... displacement due to thermal deformation of end plate, c ... displacement due to thermal deformation of scroll wrap. Here, FIGS. 2 to 4 show the deformed state of the first scroll member and FIGS. 5 to 7 show the deformed state of the second scroll member. The first scroll member will be examined with reference to FIGS.

First, FIG. 2 shows an outline of pressure deformation. Since the scroll member has a shape in which the scroll wrap stands on the end plate, the displacement of the end plate, that is, the displacement of the scroll wrap root and the scroll wrap. The tooth tip displacements are substantially the same. Therefore, it is considered the same here,

[0009]

## EQU1 ## d _1a (r) = D _1a (r) (Equation 1) holds. Next, in order to investigate the thermal deformation, the displacement due to the thermal deformation of the end plate and the displacement due to the thermal deformation of the scroll wrap were divided into two. First, the former is shown in FIG. This is the displacement that occurs when there is a temperature difference between the two surfaces of the end plate, as shown in FIG.
Shows the case where the upper surface of the end plate has a higher temperature than the lower surface.
The same can be said here as in FIG.

[0010]

## EQU00002 ## d _1b (r) = D _1b (r) (Equation 2) is established. Next, FIG. 4 shows the displacement of the latter scroll wrap due to thermal deformation. FIG. 4 shows a case where the temperature of the center of the scroll wrap is higher than that of the surroundings.

The same applies to the second scroll member, and the respective displacement amounts are shown in FIGS. 5 to 7.
Further, a relational expression similar to the relational expression described above is established as follows.

[0012]

D _2a (r) = D _2a (r) (Equation 3)

[0013]

## _EQU00004 ## d _2b (r) = D _2b (r) (Equation 4) From these, the displacements of the tooth bottom and tooth tip of the scroll member are obtained as follows.

[0014]

[Equation 5] Root displacement of the first scroll wrap = d _1a (r) + d _1b (r) (Equation 5)

[0015]

[Equation 6] Tooth tip displacement of the first scroll wrap = D _1a (r) + D _1b (r) + D _1c (r) ... (Equation 6)

[0016]

## EQU00007 ## The bottom displacement of the second scroll wrap = _d.sub.2a (r) + _d.sub.2b (r) (Equation 7)

[0017]

[Equation 8] Displacement of the tip of the second scroll wrap = D _2a (r) + D _2b (r) + D _2c (r) (Equation 8) Therefore,

[0018]

## EQU00009 ## A displacement difference at r = tooth tip displacement at r of the second scroll lap-root displacement at r of the first scroll lap = D _2a (r) + D _2b (r) + D _2c (r) -D _1a (r) -d _1b (r) (∵number 8, number 5) ... (number 9)

[0019]

## EQU10 ## B displacement difference at r = root displacement at r of the second scroll lap-tip displacement at r of the first scroll lap = d _2a (r) + d _2b (r) -D _1a (r ) -D _1b (r) -D _1c (r) = D _2a (r) + D _2b (r) -d _1a (r) -d _1b (r) -D _1c (r) (∵ number 7, number 5, Formula 1, Formula 2, Formula 3, Formula 4) ... (Formula 10) From this, it can be seen that both the A displacement difference at r and the B displacement difference at r depend on both the pressure deformation and thermal deformation of the first scroll member and the pressure deformation and thermal deformation of the second scroll member. It shows that both the A displacement difference and the B displacement difference depend not only on the thermal expansion coefficient of the two scroll members but also on the temperature distribution, as well as the Young's modulus and the pressure distribution. However, focusing on the difference between the A displacement difference and the B displacement difference at the same r, many terms cancel each other out, and the following extremely simple relationship is found.

[0020]

[Equation 11] A displacement difference at r−B displacement difference at r = D _2c (r) + D _1c (r) (∵Equations 9 and 10) (Equation 11) Here, this result is easy to understand. In order to do so, the following two quantities are introduced.

Δ _1c (r): Elongation (expansion) of the wrap at r due to thermal deformation of the first scroll lap δ _2c (r): Elongation (expansion) of r at the r due to thermal deformation of the second scroll lap From this,

[0022]

[Equation 12] δ _1c (r) = − D _1c (r) (Equation 12)

[0023]

Since δ _2c (r) = D _2c (r) (Equation 13), Equation 11 becomes

[0024]

[Expression 14] A displacement difference at r−B displacement difference at r = δ _2c (r) −δ _1c (r) (Expression 14) By the way, the amount of elongation of the lap is the amount of temperature increase (denoted as ΔT) from the time of assembling the wrap, the coefficient of thermal expansion of the lap (denoted as K), and the height of the lap during the assembling (denoted as h).
If you ask, it will come out, so

[0025]

## _EQU15 ## δ _1c (r) = ΔT ₁ (r) × h ₁ (r) × K ₁ (Equation 15)

[0026]

## _EQU16 ## δ _2c (r) = ΔT ₂ (r) × h ₂ (r) × K ₂ (Equation 16) Here, the subscripts of ΔT (r), h (r), and K represent that 1 is an amount related to the first scroll member and 2 is an amount related to the second scroll member. By the way, since the amount of temperature increase of the wrap roughly depends on the temperature of the compressible fluid targeted by this fluid machine, even if the scroll wraps of different scroll members have the same degree of compression of the compressible fluid at the same position. The temperatures can be considered the same. Further, at the positions where the distance from the center of the scroll wrap is the same in the first scroll member and the second scroll member, the degree of compression of the compressive fluid is similar, and therefore it is considered that the following relationship is established.

[0027]

ΔT ₂ (r) = ΔT ₁ (r) (Equation 17) Further, the wrap height at the time of assembly strictly depends on the scroll member and r, but the dependent amount does not depend on it. Since the sizes are different from each other in comparison, it may be considered as a constant (represented as H) irrelevant to the difference of scroll members and r as follows.

[0028]

[Equation 18] h ₁ (r) = h ₂ (r) = H (Equation 18) Using Equations 17 and 18, Equations 15 and 16 are

[0029]

[Formula 19] δ _1c (r) = ΔT ₁ (r) × K ₁ × H (Formula 19)

[0030]

[Equation 20] δ _2c (r) = ΔT ₁ (r) × K ₂ × H (Equation 20) From this, the number 14 is

[0031]

[Equation 21] A displacement difference at r−B displacement difference at r = ΔT ₁ (r) × (K ₂ −K ₁ ) × H (∵ Equation 14, Equation 19, Equation 20) (Equation 21) You can see that it is represented.

From this equation 21, since both H and ΔT ₁ (r) are positive values, the magnitude relationship between the A displacement difference and the B displacement difference at the same r depends on the thermal expansion coefficient of the first scroll lap and the second scroll lap. K ₁ > K ₂ ⇒ A displacement difference <B displacement difference K ₁ <K ₂ ⇒ all r, A displacement difference> B displacement difference K ₂ = K ₁ ⇒ all At r, a relationship such as A displacement difference = B displacement difference is derived. Since these relationships were derived after making some assumptions, they are considered to be roughly established. Therefore, K ₁ > K ₂ ⇒ In most r, A displacement difference <B displacement difference K ₁ <K ₂ ⇒ In most r, A displacement difference> B displacement difference K ₂ = K ₁ ⇒ In most r, A It is considered that a relationship such as displacement difference = B displacement difference is established.

From the above, during operation, the gap between the roots of the first scroll wrap and the tops of the second scroll wrap and the gap between the tops of the first scroll wrap and the bottoms of the second scroll wraps are substantially eliminated over the entire area. Since there is almost no contact between them, the internal leakage of the compressible fluid of interest can be suppressed and the friction loss can be reduced. As a result, the performance of the fluid machine can be improved.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. 1, 8, 9 and 10.

FIG. 1 is a vertical sectional view of a hermetic type air-conditioning scroll compressor according to a first embodiment of the present invention at the time of assembly, FIG. 8 is a bottom view of a fixed scroll in its compression mechanism portion, and FIG. FIG. 10 is a vertical cross-sectional view of the fixed scroll and the orbiting scroll in the compression mechanism section, and FIG. 10 is a distribution diagram of the gap between the tip and the root of the fixed scroll and the orbiting scroll in the compression mechanism section. First, the overall configuration will be described.

In the scroll compressor shown in FIG. 1, a compression mechanism part is housed in the upper part of the closed container 1, and an electric motor part is housed in the lower part.
A reservoir for storing lubricating oil is provided at the bottom.

The compression mechanism section mainly includes a fixed scroll member 2 made of cast iron, an orbiting scroll member 3 made of aluminum having a thermal expansion coefficient larger than that of cast iron 3, a frame 4, and an Oldham ring 5. The fixed scroll member 2 is an end plate 2a.
And a scroll wrap 2b having an involute curve of a circle which is almost upright on its inner and outer surfaces and an end plate 2c for supporting the end plate 2a. The lower surface of the end plate 2c is the first reference surface 2d, and this surface 2d and the tooth top surface 2e of the scroll wrap 2b are the same surface. The tooth bottom surface 2f is the first reference surface 2d.
It is a plane almost parallel to. The orbiting scroll 3 is an end plate 3
a and a scroll wrap 3b having an involute curve of a circle substantially upright on its inner and outer surfaces, a boss portion 3g, and a swivel bearing 3h press-fitted into the boss portion 3g. The upper surface of the outer peripheral portion of the end plate 3a is the second reference surface 3d, which directly contacts the first reference surface 2d of the fixed scroll 2 during operation to define the gap between the fixed scroll 2 and the orbiting scroll 3 in the scroll wrap standing direction. , The scroll wraps 2b, 3b are inwardly meshed with each other to form a compression chamber 6. Here, when the first reference surface 2d of the fixed scroll 2 and the second reference surface 3d of the orbiting scroll 3 are in contact with each other when the operation is stopped, the tip 3e of the orbiting scroll 3 and the fixed scroll 2 are in contact with each other.
The gap 7 that is the gap between the bottom of the scroll wrap and the bottom of the scroll wrap is larger than the gap 8 that is the gap between the bottom 3f of the orbiting scroll 3 and the tip 2e of the fixed scroll. The tooth tip 3e and the tooth bottom 3
Set f. The gap and the difference between the gaps can be set by using the equation 21 described in the operation. As in this example,
In the case of a hermetic compressor, the upper limit of the discharge temperature of the refrigerant gas is determined by the heat resistance of the stator of the electric motor. In the case of a room air conditioner compressor, when an ordinary heat-resistant stator is used, the temperature is about 100 ° C. Therefore, if the temperature at the time of assembly is 20 ° C., the value of ΔT ₁ in Equation 21 is 8 near the center of the scroll wrap, which is the discharge portion of the refrigerant gas.
It becomes 0 ° C. The coefficient of thermal expansion of cast iron is 0.000012.
/ ° C, and the coefficient of thermal expansion of aluminum is 0.000018 / ° C, so the value of K ₂ -K ₁ is 0.000006 / ° C. Therefore, when H is 0.02 m, the difference between the gap 7 and the gap 8 near the center of the scroll lap is 0.0000096 m, that is, about 10 μ
It turns out that it is m. In addition, the difference between the gap 7 and the gap 8 near the outer circumference of the scroll wrap, which is the suction port for the refrigerant gas, is about 3 μm when the temperature difference ΔT ₁ there is considered to be 20 ° C.
Becomes By giving a difference between the gap 7 and the gap 8 in this way, the fixed scroll 2 and the orbiting scroll 3 are orbited without making contact between the tips and bottoms of the fixed scroll 2 and the orbiting scroll 3 when both the gap 7 and the gap 8 are small during operation. Since the scroll 3 can be operated while stably contacting between the first reference surface 2d and the second reference surface 3d, internal leakage of the refrigerant gas is suppressed and friction loss is reduced, and the stable contact allows the scroll wrap between the scroll wraps to be reduced. Since the oil film that seals the gap is stably formed, internal leakage of the refrigerant gas is further suppressed, and the compressor has high performance. Even when the fixed scroll 2 and the orbiting scroll 3 come into contact with the tooth tips and the bottoms of the orbiting scroll 3 and the orbiting scroll 3 moves downward, and the gap on the non-contacting side expands, when the gap setting contrary to the present invention is made. On the other hand, since the non-contact gap is small, the internal leakage of the refrigerant gas is small, and the compressor can maintain high performance. In the present embodiment, the gap 7 and the gap 8 are set in a stepwise manner so that the gap 7 and the gap 8 both increase from the outer periphery toward the center. Here, the step is provided along an ideal curve such that the reduction rate of the gap with respect to the involute winding angle increases toward the center as shown by the broken line in FIG. As for the method of forming the steps, the stepped portions may be provided at positions of winding angles that are substantially evenly spaced as shown in FIG. 11, or may be provided at a substantially equal distance along the involute. Further, the step amounts may be set to be substantially constant and the step positions may be arranged at unequal intervals. Further, the amount of step difference may be indefinite, and the step positions may of course be arranged at unequal intervals. Further, the gap 8 near the center of the winding end portion of the scroll wrap 2b, which is in contact with the fixed suction groove 2n, is locally enlarged. In addition, in both gaps 7 and 8, a gap is provided over the entire region from the beginning of winding to the end of winding, and both reference surfaces 2d and 3d and tooth top surfaces and tooth bottom surfaces 2e, 3e,
Let 2f and 3f be different surfaces. A suction pipe 9 connected to an external refrigeration cycle is provided in the suction chamber 2i of the fixed scroll 2, and a check valve 10 and a valve spring 11 supporting the check valve 10 are inserted in the suction chamber 2i. Further, the suction groove 2n is provided between the winding end portion of the scroll wrap 2b and the reference surface 2d. The eccentric portion 12a of the crankshaft 12 inserted into the main bearing 4a at the center of the frame 4 is rotatably inserted into the orbiting bearing 3h at the boss portion 3g of the orbiting scroll 3, and is formed into a groove (not shown) on the rear surface of the end plate 3a. Oldham groove 4 of frame 4
An Oldham ring 5 is slidably arranged in b.
Further, an intermediate pressure hole 3j is provided which connects the compression chamber 6 in the middle of the compression process and the back surface of the end plate 3a, and the pressure of the intermediate pressure chamber 13 formed by the frame 4 and the end plate 3a of the orbiting scroll 3 is sucked in during operation. Lower pressure than chamber 2i. In this way, by making the resultant force of the pressure on the rear surface side of the end plate 3a larger than the resultant force of the pressure on the front surface, the orbiting scroll 3 is pressed against the fixed scroll 2 during operation, and the first reference surface 2d and the second reference surface 2d The reference surface 3d is made to contact. The fixed scroll 2 is fastened to the frame 4 by bolts 14 at the outer peripheral portion thereof, and the outer peripheral side surface portion of the frame 4 is fixed to the closed container 1 by welding or the like.

The electric motor section includes the crankshaft 12 and the rotor 1.
5, The stator 16 is a main component. A rotor 15 forming an electric motor is fitted to the crankshaft 12 by shrink fitting, and a stator 16 forming the electric motor is fixed in the sealed container 1 by shrink fitting. An upper balance weight 15a is fixed to the upper surface of the rotor 15 and a lower balance weight 15b is fixed to the lower surface thereof, so that the rotating portion is rotationally balanced.

The reservoir portion has a sub-bearing 17 for supporting the lower portion of the crankshaft 5 and a holding plate 18 for holding the auxiliary bearing 17, and lubricating oil 19 is stored therein. The holding plate 18 is fixed to the closed container 1 by welding or the like. The lower end of the crankshaft 12 is immersed in the lubricating oil 19, and the crankshaft 12 is provided with an oil supply passage 12b penetrating in the axial direction and a lubricating oil supply hole 12c provided in the middle thereof and communicating with the main bearing 4a.

Next, the operation of the scroll compressor will be described. The rotor 15 receives a rotational force from the stator 16, the crankshaft 12 rotates, and the orbiting scroll 3 revolves by the action of the Oldham ring 5 without rotating. The refrigerant gas sucked through the suction pipe 9 by the revolution of the orbiting scroll 3 is supplied to the entire suction chamber 2i through the suction groove 2n and the like, and is gradually compressed in the compression chamber 6 to the discharge port 2k.
And is discharged to the discharge chamber 20 above the end plate 2a. The discharged refrigerant gas enters the electric motor chamber 21, where the oil in the gas is separated and the electric motor is cooled, and then supplied from the discharge pipe 22 to the external refrigeration cycle. The lower end of the crankshaft 12 is immersed in the lubricating oil 19, and the oil supply passage 12b penetrating the crankshaft 12 in the axial direction and the main bearing 4 provided in the middle thereof are provided.
The lubricating oil 19 is supplied to the orbiting bearing 3h and the main bearing 4a by a pressure difference through the lubricating oil supply hole 12c communicating with a.
The sub bearing 17 is immersed in the lubricating oil 19 or lubricated by the oil in the refrigerant gas.

According to this embodiment, the end plate 2 based on the gas pressure is used.
The displacement of "a" is such that the central portion is dented as shown in FIG. 2 because the high pressure discharge gas is present in the upper portion of the fixed scroll 2. Further, the displacement of the end plate 2a due to heat is such that the entire upper part is shifted upward and the central part is bulged as shown in FIG. 3 because the hot gas is present in the upper part of the fixed scroll 2 and the outer periphery of the end plate base 2c. It becomes a situation. Further, the displacement of the end plate 2a due to heat is caused by the upper portion of the fixed scroll 2 and the end plate 2c.
Since there is a high-temperature discharge gas on the outer periphery of the above, the whole state shifts upward and the central part bulges as shown in FIG. However, this bulge is so small that it can be ignored. Furthermore, the tooth top 2e of the scroll wrap 2b due to heat
The temperature of the scroll wrap 2b is much higher than that of the center of the scroll wrap 2b because the temperature rises due to adiabatic compression as the refrigerant gas goes from the outer periphery to the center. Similar displacements also occur in the orbiting scroll 3, which results in the situation shown in FIGS. From the above, it can be seen that the displacement amount during operation is larger in the central portion than in the surroundings. In the present embodiment, the gap 7 and the gap 8 during assembly are set to increase from the outer circumference toward the center, so that the gap 7 and the gap 8 during operation can be kept small over the entire area.
The internal leakage of the refrigerant gas can be further suppressed.

In addition, in the gaps 7 and 8, a gap is provided over the entire area from the start of winding to the end of winding, and both reference surfaces 2
Since d and 3d are different from the tooth top surfaces and the tooth bottom surfaces 2e, 3e, 2f, and 3f, the reference surface processing can be performed by a highly accurate method such as optimal polishing, and the movement of the orbiting scroll 3 can be stabilized. . Therefore, the oil film in the gap between the scroll wraps can be stably formed, so that the internal leakage of the refrigerant gas can be suppressed.

Further, since the gap 8 near the center of the winding end of the scroll wrap 2b which is in contact with the fixed suction groove 2n is locally enlarged, the heat from the outer periphery of the fixed scroll member at high temperature at the bottom of the fixed suction groove 2n is increased. It is possible to avoid contact between both scroll members due to local expansion of the scroll wrap due to inflow.

In the present embodiment, the intermediate pressure chamber is provided and the orbiting scroll member 3 is directly pressed against the fixed scroll member 2 to define the distance between both scrolls, but the pressure inside the closed container 1 is low. End plate 3 of the orbiting scroll member 3
The same effect can be obtained even when the present invention is carried out in a compressor of the type in which the fixed scroll member 2 is pressed against the fixed frame 4 with the lower surface of a as the reference surface 3d. Furthermore, the fixed suction groove 2n
Is deepened to the same extent as the tooth bottom 2f to suppress heat inflow from the outer periphery of the fixed scroll member at high temperature.
It is also possible to suppress the local extension of the scroll wrap near the center of the winding end part and to eliminate the local expansion of the outer peripheral part of the gap 8.

Next, a second embodiment of the present invention will be described with reference to FIG.

FIG. 11 is a vertical sectional view of the fixed scroll 2 and the orbiting scroll 3 in the compression mechanism portion of the air conditioning scroll compressor according to the second embodiment of the present invention when the operation is stopped. The material of the orbiting scroll 3 is the same cast iron as that of the fixed scroll 2, and accordingly, when the first reference surface 2d of the fixed scroll 2 and the second reference surface 3d of the orbiting scroll 3 are in contact with each other when operation is stopped, a gap is formed. 7 and gap 8
Is the same as that of the first embodiment except that the tooth top 3e and the tooth bottom 3f are set to be substantially the same at a position where the distance from the center of the scroll wrap is substantially the same, and therefore, other configurations and operations are The description is omitted.

According to this embodiment, the rigidity of the scroll wrap 3b of the orbiting scroll 3 is high, so that the teeth can be made high, whereby the outer diameter of the compressor can be made small without reducing the stroke volume.

Next, a third embodiment of the present invention will be described with reference to FIG.

FIG. 12 is a vertical cross-sectional view of the fixed scroll 2 and the orbiting scroll 3 in the compression mechanism portion of the air-conditioning scroll compressor according to the third embodiment of the present invention when the operation is stopped. The first reference surface 2d of the fixed scroll 2 when the operation is stopped
When the orbiting scroll 3 and the second reference surface 3d of the orbiting scroll 3 are in contact with each other, the gap 7 is set such that the tooth tip 3e of the orbiting scroll 3 is one plane and the root 2f of the fixed scroll 2 is tapered or stepwise. Except for this point, the configuration is the same as that of the first embodiment, and the description of other configurations and operations is omitted.

According to this embodiment, since the tooth tip 3e of the orbiting scroll 3 can be processed by highly accurate lapping, the gap 7 can be set with high accuracy, and the internal leakage of the refrigerant gas can be further suppressed.

Next, a fourth embodiment of the present invention will be described with reference to FIG.

FIG. 13 is a vertical sectional view of the fixed scroll 2 and the orbiting scroll 3 in the compression mechanism portion of the air conditioning scroll compressor according to the fourth embodiment of the present invention when the operation is stopped. The first reference surface 2d of the fixed scroll 2 when the operation is stopped
When the orbiting scroll 3 and the second reference surface 3d of the orbiting scroll 3 are in contact with each other, the gap 8 is set such that the tooth bottom 3f of the orbiting scroll 3 is one plane and the tip 2e of the fixed scroll 2 is tapered or stepwise. Except for this point, the configuration is the same as that of the first embodiment, and the description of other configurations and operations is omitted.

According to the present embodiment, both the gap 7 and the gap 8 are set by machining the tooth tips 2e, 3e in a taper or step shape, but the machining resistance applied to the end mill at this time is usually small. , The gap 7 and the gap 8 can be set with high accuracy, and the internal leakage of the refrigerant gas can be further suppressed.

Next, a fifth embodiment of the present invention will be described with reference to FIG.

FIG. 14 is a vertical sectional view of the fixed scroll 2 and the orbiting scroll 3 in the compression mechanism portion of the air conditioning scroll compressor according to the fifth embodiment of the present invention when the operation is stopped. The first reference surface 2d of the fixed scroll 2 when the operation is stopped
And the second reference surface 3d of the orbiting scroll 3 are in contact with each other, the tooth tops 3e and the tooth bottoms 3f of the orbiting scroll 3 are both in a single plane, and the gaps 7 and 8 are of substantially uniform size regardless of the location. Other than that, the configuration is the same as that of the first embodiment, and therefore the description of other configurations and operations will be omitted.

According to this embodiment, since the tooth tips 2e, 3e and the tooth bottoms 2f, 3f are all machined on one side, the orbiting scroll 3 and the fixed scroll 2 can be easily machined and the machining cost can be reduced.

Next, a sixth embodiment of the present invention will be described with reference to FIG.

FIG. 15 is a vertical sectional view of the fixed scroll 2 and the orbiting scroll 3 in the compression mechanism portion of the air conditioning scroll compressor according to the sixth embodiment of the present invention when the operation is stopped. The first reference surface 2d of the fixed scroll 2 when the operation is stopped
And the second reference surface 3d of the orbiting scroll 3 are in contact with each other, the tooth tip 3e of the orbiting scroll 3 is tapered or stepped, and only the gap 7 is enlarged toward the center. Since it is the same, description of other configurations and operations will be omitted.

According to the present embodiment, the machining cost can be reduced and the size of the gap 7 can be suppressed during the operation, so that the internal leakage of the refrigerant gas can be suppressed.

Next, a seventh embodiment of the present invention will be described with reference to FIG.

FIG. 16 is a vertical sectional view of the fixed scroll 2 and the orbiting scroll 3 in the compression mechanism portion of the air-conditioning scroll compressor according to the seventh embodiment of the present invention when the operation is stopped. Tip 2e of fixed scroll 2 and orbiting scroll 3
Since the third embodiment is the same as the first embodiment except that the tip seals 2L, 3L and the seal leaf springs 2m, 3m are set on each of the tooth tips 3e, the description of other configurations and operations will be omitted.

According to this embodiment, both the gap 7 and the gap 8 during operation are closed by the tip seals 2L and 3L, so that the internal leakage of the refrigerant gas can be further suppressed.

Next, an eighth embodiment of the present invention will be described with reference to FIG.

FIG. 17 is a vertical sectional view of the fixed scroll 2 and the orbiting scroll 3 in the compression mechanism portion of the air-conditioning scroll compressor according to the eighth embodiment of the present invention when the operation is stopped. Tip 2e of fixed scroll 2 and orbiting scroll 3
The fifth embodiment is the same as the fifth embodiment except that the tip seals 2L, 3L and the seal leaf springs 2m, 3m are set on each of the tooth tops 3e, so that the description of other configurations and operations will be omitted.

According to this embodiment, the machining cost is reduced, and the gap 7 and the gap 8 during operation are both chip seals 2.
Since it is blocked by L and 3L, internal leakage of the refrigerant gas can be suppressed.

Next, a ninth embodiment of the present invention will be described with reference to FIG.

FIG. 18 is a longitudinal sectional view of the fixed scroll 2 and the orbiting scroll 3 in the compression mechanism portion of the air-conditioning scroll compressor according to the ninth embodiment of the present invention when the operation is stopped. Tip seal 3L on tip 3e of orbiting scroll 3
Since the third embodiment is the same as the eighth embodiment except that the seal leaf spring 3m is set, the description of other configurations and operations will be omitted.

According to the present embodiment, the tip seal 3L can suppress the leakage of the refrigerant gas only in the gap 7 in which a large gap is likely to be formed during the operation.

[0069]

According to the present invention, even when the materials of the orbiting scroll and the fixed scroll are different from each other, the gap between the addendum and the addendum of the scroll wrap during operation can be made small in the entire area, and therefore the present invention is intended. Leakage between the tip and the bottom of the scroll wrap of the compressible fluid can be suppressed.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a first embodiment.

FIG. 2 is an explanatory view of pressure deformation of a first scroll member.

FIG. 3 is an explanatory view of thermal deformation of an end plate portion of the first scroll member.

FIG. 4 is an explanatory diagram of thermal deformation of a scroll wrap portion of the first scroll member.

FIG. 5 is an explanatory diagram of pressure deformation of a second scroll member.

FIG. 6 is an explanatory diagram of thermal deformation of an end plate portion of the second scroll member.

FIG. 7 is an explanatory diagram of thermal deformation of the scroll wrap portion of the second scroll member.

FIG. 8 is a bottom view of the fixed scroll member of the first embodiment.

FIG. 9 is a vertical cross-sectional view of the main part of the compression mechanism of the first embodiment.

FIG. 10 is a gap distribution diagram of the first embodiment.

FIG. 11 is a vertical cross-sectional view of the main part of the compression mechanism of the second embodiment.

FIG. 12 is a vertical cross-sectional view of the main part of the compression mechanism of the third embodiment.

FIG. 13 is a vertical cross-sectional view of the main part of the compression mechanism of the fourth embodiment.

FIG. 14 is a vertical cross-sectional view of the main part of the compression mechanism of the fifth embodiment.

FIG. 15 is a vertical cross-sectional view of the main part of the compression mechanism of the sixth embodiment.

FIG. 16 is a vertical cross-sectional view of the main part of the compression mechanism of the seventh embodiment.

FIG. 17 is a vertical cross-sectional view of the main part of the compression mechanism of the eighth embodiment.

FIG. 18 is a vertical cross-sectional view of the main part of the compression mechanism of the ninth embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Airtight container, 2 ... Fixed scroll member, 3 ... Orbiting scroll member, 2a, 3a ... End plate, 2b, 3b ... Scroll wrap, 2d ... 1st reference surface, 2L, 3L ... Chip seal, 3d ... 2nd reference surface 5 ... Oldham ring, 6 ... Compression chamber, 7 ... Gap, 8 ... Gap, 12 ... Crank shaft, 13 ... Intermediate pressure chamber, 15 ... Rotor, 16 ... Stator.

Claims (1)

[Claims] 1. A first scroll member composed of a first end plate and a first scroll wrap having an involute curve or a curved shape similar to the first end plate, which is erected upright, and a second end plate and upright. A second scroll member consisting of a second scroll wrap having an involute curve or a curved shape similar to that to be set, the upright directions of the scroll wraps are substantially coincident with each other, and the scroll wraps are engaged with each other by facing each other,
The second scroll member viewed from the first scroll member has a rotation center about an axis substantially parallel to the upright direction of each scroll wrap without rotation about an axis substantially parallel to the upright direction of each wrap. In the scroll fluid machine configured to perform the orbiting motion described above, a part of the first scroll member or a member that moves integrally with the first scroll member and a first reference surface that defines the distance between the scroll members in the wrap upright direction during operation. A part of the second scroll member or a member that moves integrally with the second scroll member is provided with a second reference surface that defines the distance between the scroll members in the wrap upright direction during operation, and both are defined by the first and second reference surfaces during assembly. In a prescribed state of the distance between the scroll members, the tooth gap between the tooth bottom of the first scroll wrap and the tooth tips of the second scroll wrap and the first scroll. A gap is provided between the tip of the roll wrap and the bottom of the second scroll wrap, and the magnitude relationship between them is determined by the coefficient of thermal expansion of the first scroll wrap at the temperature near the scroll wrap during compressor operation to be the second. When the coefficient of thermal expansion of the scroll wrap is higher than that at the temperature, the latter gap is made larger than the former gap at positions at substantially the same distance in the radial direction from the center of the scroll of each scroll wrap, and the scroll wrap during compressor operation When the coefficient of thermal expansion of the first scroll wrap at a temperature in the vicinity is smaller than the coefficient of thermal expansion of the second scroll wrap at the temperature, the latter at a position substantially the same distance from the center of the spiral of each scroll wrap in the radial direction. The gap is made smaller than the former gap, and the first screw at the temperature near the scroll wrap during compressor operation is used. When the coefficient of thermal expansion of the roll wrap and the coefficient of thermal expansion of the second scroll wrap at the temperature are substantially the same, the former gap and the latter gap are located at substantially the same distance in the radial direction from the center of the spiral of each scroll wrap. A scroll fluid machine characterized in that