KR20000069162A - Fluid compressor - Google Patents

Abstract

The present invention relates to a fluid compressor, the fluid compressor comprising a spiral blade type compression mechanism, comprising: a cylinder; A roller disposed inside the cylinder; And a spiral blade sandwiched between the roller and the cylinder, wherein the blade, the roller, and the cylinder are formed of a material having a coefficient of thermal expansion that satisfies the relationship of blade > roller > It is easily executed in the case under low temperature conditions, and the compressive performance can be improved under high temperature conditions during operation.

Description

Fluid Compressor {FLUID COMPRESSOR}

Recently, a fluid compressor called a helical blade compressor has been proposed. In this type of compressor, the cylinder is arranged in a sealed case, and the roller serves as a rotating member disposed eccentrically inside the cylinder. Inside the cylinder the roller rotates or pivots around a given axis.

The blade is sandwiched between the circumferential surface of the roller and the inner circumferential surface of the cylinder, thereby forming a plurality of compression chambers. The refrigerant gas (ie, gas compressed in the refrigeration cycle) is sucked into one side of the compression chamber. The refrigerant gas is gradually compressed while moving to the other side.

Unlike conventional reciprocating or rotary compressors, this type of compressor can ensure sealing properties despite its simple structure. In addition, effective compression is possible and is easy to assemble with the use of easily manufactured parts.

Most of the parts constituting the compression mechanism are made of iron-based material. Wear resistance is required because the components of the compression mechanism slide in relation to each other. Therefore, it is usually made of cast iron or sintered metal.

Each part forms a compression chamber jointly and has a function of sealing the gas. If these parts are formed of the same iron-based material, they have the same coefficient of thermal expansion, and the clearance between them remains unchanged regardless of temperature change. Therefore, the use of the same iron-based material makes it possible to narrow the clearance as much as possible, contributing to the improvement of the compression performance.

However, if the clearance between the parts is very narrow, the gas cannot easily escape when the pressure in the compression chamber rises rapidly in the case of fluid backflow. Pressure relief mechanisms are provided to cope with this situation, but this complicates the structure.

In addition, in this type of compressor, the relative circumferential speed between the blade and the roller and the roller and the bearing is very slow. Since these parts of the compressor are easily set to boundary lubrication conditions when the compressor is driven, the roller is made of a wear resistant material such as cast iron having a relatively large weight. The use of these materials has enhanced reliability (improved wear resistance) even under boundary lubrication conditions.

However, cast iron rollers with a large weight have the drawback of having a large inertia gravity when the compressor is driven and a lack of vibration suppression force. Therefore, the roller is preferably as light as possible to suppress vibration and noise and improve performance.

The blade is made of a fluoroplastic material such as tetraethylene fluoride resin (hereinafter referred to as "PTFE resin") or perfluoroalkoxy resin (hereinafter referred to as "PFA resin"), and the use of such material is low in plasticity. This has improved sealing properties, sliding properties and environmental resistance (temperature, oil and refrigerant).

In order to improve the wear resistance, the blade is molded from a composite material. That is, inorganic fibers (ie, glass fibers and carbon fibers), solid lubricants, and organic additives are contained in the material of the blade.

Since the fluoroplastic material varies greatly in size upon thermal expansion, the clearances a and b between the blade D and the helical grooves H formed in the piston P disposed inside the cylinder C have the highest temperature. The minimum value is set in consideration of the compression efficiency and the size change of the blade D due to thermal expansion.

However, if the clearance is set or determined in this manner, the clearance may become too large when the compression operation is just beginning or in other low temperature situations. When this situation occurs, the sealing property between the components is degraded, so that the planned compression performance cannot be obtained.

The fluoroplastic blade D is soft and can be easily bent by pressure difference. In addition, as shown in FIG. 14, the blade D may be rubbed with the edge portion Z of the helical blade H on one side. In addition, the elastic modulus can also be reduced by thermal expansion, so that the blade can be permanently deformed under excessively high pressure conditions.

The present invention relates to a fluid compressor mounted on a refrigeration cycle apparatus for compressing refrigerant gas (ie, compressed gas) with a spiral blade type compression mechanism.

1 is a sectional view of a helical blade compressor according to a first embodiment of the present invention;

2A and 2B show the clearance of the first embodiment;

3A and 3B show a transceiver plating layer formed on the roller surface of the first embodiment;

4 shows the amount of wear of the helical groove of the roller according to the operating time of the first embodiment;

Fig. 5 is a diagram showing the amount of wear at the Oldhams mechanism sliding portion of the roller according to the operating time of the first embodiment;

6 shows a hollow structure of a blade of a compression mechanism part of the second embodiment;

7A-7C illustrate a blade structure of the present invention;

8A is a diagram showing an example of a gas assisted molding method;

8B is a view showing another example of the gas support molding method;

8C is a view showing another example of the gas support molding method;

9 is a view showing a comparison between the gas assisted molding efficiency according to the second embodiment and the gas assisted molding efficiency according to the comparative example;

10A and 10B are diagrams illustrating the generation of shrinkage marks on blades manufactured according to embodiments of the present invention;

11A and 11B show hollow portions of a blade cross section according to a comparative example;

12A and 12B are cross-sectional views showing hollow portions of a blade cross section according to an embodiment of the present invention;

13 illustrates clearance between components of the prior art; And

14 is a view showing a modified state of a blade of the prior art.

It is a first object of the present invention to provide a fluid compressor which can easily discharge pressure under low pressure conditions at the initial stage of backflow or compression operation of a fluid in a compressor, thereby enhancing compression performance under high temperature conditions during operation.

A second object of the present invention is to provide a fluid compressor that can form a roller of a pre-selected material, which is light in weight, greatly improving wear resistance, and suppresses vibration and noise to improve compression performance.

A third object of the present invention is to provide a fluid compressor which can improve the compression performance by suppressing the effects of thermal expansion and pressure conditions that can be imparted to the spiral blade by using a preselected material for forming the spiral blade.

The first invention of the invention relates to the above-mentioned first object and is described in claim 1. The fluid compressor according to claim 1 includes a spiral blade type compression mechanism comprising a cylinder, a rotating member disposed inside the cylinder, and a spiral blade sandwiched between the rotating member and the cylinder. A feature of the fluid compressor is that the cylinder, the rotating member, and the cylinder are formed of a material having a coefficient of thermal expansion satisfying the following relational expression.

Blade〉 Rotating Material〉 Cylinder

The second invention of the invention relates to the foregoing second object and is described in claim 3. The fluid compressor according to claim 3 is based on the fluid compressor described above, and the rotating member is formed of an aluminum alloy material. The third invention of the present invention relates to the above-mentioned third object and is disclosed in claim 12. The fluid compressor according to claim 12 is a PEEK (polyether ether ketone) resin material, PES (polyether sulfone) resin material, PEI (polyether imide) resin material, PAI (polyamide imide) resin material, TPI (thermoplastic polyimide) The blade is formed from a material selected from the group consisting of a mid) resin material, an LCP (liquid crystalline polymer such as all kinds of aromatic polyester) resin material, and a PPS (polyphenylene sulfide) resin material.

According to the first invention, the pressure relief can be easily carried out in the case under fluid backflow or low pressure conditions depending on the operating time. In addition, the compression performance can be improved under high pressure conditions during operation.

According to the second invention, the roller (i.e., the rotating member) is molded from a preselected material so that the weight is light and wear resistance can be greatly improved. Thus, vibration and noise are also reduced and compression performance is improved.

It is a third object of the present invention to provide a fluid compressor with improved compression performance by suppressing the effects of thermal expansion and pressure conditions that can be imparted to a spiral blade by using a preselected material for forming the spiral blade.

Embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Spiral blade compressors are used in refrigeration cycles of air conditioners. The fluid to be compressed is a refrigerant gas.

As shown in Fig. 1, the sealing case 1 has a shaft extending in the vertical direction and has a main opening main body 1a having two opening ends, and an upper part sealing the upper opening end of the main case main body 1a. The lid 1b and the lower lid 1c which seal the lower opening end part are comprised.

The spiral blade type compression mechanism 3 and the electric motor 4 are arranged inside the sealed case 1. In Fig. 1, the compression mechanism 3 and the electric motor 4 are located in the upper and lower regions of the sealed case 1, with the border located between the shaft center of the case 1 in between.

The compression mechanism part 3 is a hollow cylinder and comprises a cylinder 5 having a pair of flanges 5a and 5b on the outer circumferential wall at each end. The flanges 5a and 5b are forcibly inserted into the main case body 1a of the case 1 to position the cylinder 5.

The main bearing 6 is fixed to the upper end face of the cylinder 5 by fixing means 7 to seal the end of the upper opening of the cylinder. The sub-bearing 8 is fixed to the lower end face of the cylinder 5 by the fixing means 7 and seals the lower opening end of the cylinder.

The crankshaft 9 is inserted between the main bearing 6 and the sub bearing 8 and extends along the axes of the bearings 6, 8. The crankshaft 9 is rotatably supported. The crankshaft 9 not only penetrates the cylinder 5 between the main bearing 6 and the sub bearing 8 but also protrudes upwards from the main bearing as shown in FIG. 1. The crankshaft 9 part which protrudes from a main bearing comprises the rotating shaft 9z of the electric motor 4. As shown in FIG.

A crank 9a is integrally provided with respect to the crankshaft 9 between the main bearing 6 and the subbearing 8.

The first reverse balancer 9b and the second reverse balancer 9c are integrally provided with respect to the crankshaft 9 on the upper and lower sides of the crank 9a. The axes of these reverse balancers 9b and 9c are shifted in the opposite direction of the crank 9a.

The roller 11 (rotating member) formed of an aluminum alloy (i.e., an aluminum material) is sandwiched between the crankshaft 9 and the cylinder 5. The roller 11 which is a cylindrical body has both ends open. The shaft length of the roller 11 is the same as the cylinder 5.

In more detail, the inner circumferential wall portion of the roller 11 opposite the crank 9a of the crankshaft 9 forms an eccentric hole 11a. The eccentric hole 11a has the same width as the crank 9a and is rotatable or sliding contact with the outer circumferential wall of the crank 9a.

The thin sleeve 12 formed of the ferrous material is forcibly inserted into contact with the inner circumferential wall of the eccentric hole portion 11a. The sleeve 12 is supported in sliding contact with the crank 9a of the crankshaft 9.

With this structure, the roller 11 is coaxial with the crank 9a, and the axis of the roller 11 is shifted from the cylinder 5 at equal intervals with the axis of the crank 9a. The outer circumferential wall of the roller 11 contacts the inner circumferential wall of the cylinder 5 so that the contact portion extends in the axial direction.

The lower part of the roller 11 is supported by the sub bearing 8, and the lower end surface of the roller 11 serves as a thruster surface. The Oldhams mechanism 13 for limiting the axial rotation of the roller 11 is sandwiched between the sub-bearing 8 and the lower end of the roller.

When the crankshaft 9 rotates, the crank 9a rotates in an eccentric manner, and the roller 11 supported on the outer circumferential wall of the crank 9a pivots about the axis of the crankshaft 9 in an eccentric manner. do. As the roller 11 rotates, the rolling contact portion between the outer circumferential surface of the roller and the inner circumferential portion of the cylinder 5 gradually moves in the circumferential direction of the cylinder 5.

The helical groove 14 is formed in the outer circumferential wall of the roller 11 so that the pitch of the groove gradually decreases from the end fixed to the sub bearing 8 to the end fixed to the main bearing 6. The helical blade 15 can be disposed along the groove in this manner and moved into or away from the groove.

The blade 15 is formed of fluoroplastic material and has an inner diameter larger than the outer diameter of the roller 11. In particular, the blade 15 is forcibly reduced in diameter and inserted into the spiral groove 14. Thus, when the roller 11 is assembled in the cylinder 5, the blade 15 expands so that the outer circumferential surface of the blade 15 remains in contact with the inner circumferential surface of the cylinder.

As described above, the rolling contact positions of the cylinder 5 and the roller 11 move in accordance with the rotation of the roller 11. The blade 15 gradually enters the helical groove 14 when the rolling contact position is close to the blade 15. When the rolling contact position is on the blade 15, its outer circumferential surface is completely flush with the outer circumferential wall of the roller.

After the rolling contact position passes through the blade 15, the blade 15 protrudes from the helical groove 14 at an interval from which the blade 15 falls from the gut contact position. The protruding length of the blade 15 is maximum when the blade 15 is 180 ° away from the rolling contact position. Thereafter, the blade 15 moves again near the rolling contact position and the above operation is repeated.

The cylinder 5 and the roller 11 are eccentric with respect to the roller 11 when the cross section is seen in the radial direction, and the circumferential surface of the roller partially contacts the cylinder. This means that a crescent shaped space is formed between the cylinder and the roller.

Viewing this space from the axial direction, the area between the roller 11 and the cylinder 5 is such that the blade 15 is disposed along the helical groove 14 of the roller 11 and the outer circumferential surface of the blade 15 is the cylinder. Because of the rolling contact with the inner circumferential surface of (5), the blade 15 is divided into a plurality of spaces.

The divided space will be referred to as compression chamber 16. Since the helical groove is formed, the volume of the compression chamber is gradually reduced from the end fixed to the sub bearing 16 to the end fixed to the main bearing 6. In addition, since the pitch of the helical groove 14 is changed, the compression chamber 16 acts as the inlet A at the lower end and acts as the outlet B at the upper end.

The suction pipe 17 communicating with the accumulator Q penetrates through the lower lid 1c of the sealed case 1. Inside the sealed case, the suction pipe 17 is connected to a gas suction port 18 provided on the circumferential surface of the lower flange 5b of the cylinder 5. The accumulator Q communicates with an evaporator (not shown) which is a component of the refrigeration cycle.

The gas suction opening 18 is an opening extending to the inner circumferential surface of the cylinder 5, and is opened to face the outer circumferential surface of the roller 11. The gas suction port 18 sucks the refrigerant gas and guides the refrigerant gas into the compression chamber 16 formed between the roller 11 and the cylinder 5.

The gas inlet 18 is located at the lower end of the cylinder 5 and communicates with one end of the compression chamber 16. The main bearing 6 is provided with a discharge hole 20 extending in parallel in the axial direction so as to discharge and guide the high pressure gas compressed in the compression chamber 16 into the sealed case 1. The discharge pipe 21 is connected to the upper lid 1b of the sealing case 1, which communicates with a condenser (not shown) constituting a part of the refrigeration cycle.

The motor portion 4 is a stator 31 attached to the rotor 30 inserted into the rotating shaft 9z of the crankshaft 9 protruding from the main bearing 6 and the inner circumferential surface of the main case body 1a. And a predetermined gap is maintained between the stator and the outer circumferential surface of the rotor 30.

In the helical bladed fluid compressor described above, power is supplied to the electric motor unit 4 so that the crankshaft 9 rotates with the rotor 30. The torque of the crankshaft 9 is transmitted to the roller 11 through the crank 9a.

Since the crank 9a is eccentric and rotatably engages with the eccentric hole portion 11a of the roller 11, the roller is pushed by the crank 9a. In addition, the Oldhams mechanism 13 is sandwiched between the roller 11 and the sub-bearing 8 which suppresses the roller 11 from its rotation. As a result, the rollers pivot around a given axis.

The low pressure refrigerant gas is sucked into the suction pipe 17 through the accumulator Q. The sucked gas is guided from the gas suction port 18 to the compression chamber 16 serving as the suction port A. Since the roller 11 pivots around a given axis, the rolling contact position on the roller contacts the inner circumferential surface of the cylinder 5 which gradually moves circumferentially. The blade 15 enters and exits the spiral groove 14. In other words, the blade 15 is inserted into the groove 14 and then projects in the radial direction of the roller.

The refrigerant gas guided to the compression chamber 16 acting as the suction port gradually flows toward the compression chamber acting as the outlet as the roller 11 rotates.

The pitch of the blade 15 gradually decreases from the inlet A to the outlet B so that the volume of the compression chamber 16 divided by the blade 15 also decreases in the same direction. Therefore, the refrigerant gas is compressed while continuously flowing through the compression chamber. When the refrigerant gas reaches the compression chamber acting as the outlet 10, the pressure is brought to a predetermined large value.

The high pressure gas is discharged from the compression chamber 16 of the discharge port B through the discharge hole 20 of the main bearing 6 and guided to the electric motor section 4, that is, the upper region of the sealing case 1. Then, the high pressure gas is led to the condenser through the discharge pipe 21 provided at the upper end of the sealed case 1.

In the above embodiment, the cylinder 5 is formed of an iron-based material, the roller 11 is formed of an aluminum alloy, and the spiral blade 15 is formed of a fluoroplastic material. The coefficient of thermal expansion of these materials satisfies the following relationship.

Blade (15)〉 Roller (11)〉 Cylinder (5)

In other words, the materials of the blade 15, the roller 11 and the cylinder 5 should be chosen to satisfy the above relation.

The compression chamber 16 is formed by the cylinder 5, the roller 11 and the blade 15, the clearance between these components affects the compression performance and gas state.

2A and 2B show that clearance is formed.

Referring to FIG. 2A, the material of the helical blade 15 entering and exiting the helical groove of the roller 11 has a larger coefficient of thermal expansion than the material of the roller 11, with the clearance c formed therebetween under low temperature conditions. Large and small under high temperature conditions.

Referring to Fig. 2B, the material of the roller 11 has a larger coefficient of thermal expansion than the material of the cylinder 5, and the clearance d formed therebetween is large under low temperature conditions and small under high temperature conditions.

During the compression operation, the clearance should be as small as possible to enhance the compression performance. When the compressor is just activated or in a low temperature condition in which the fluid flows back, the pressure in the compression chamber 16 can increase dramatically due to the compression of the fluid. Despite the sudden increase in pressure, it is necessary to leak a predetermined amount of refrigerant from the compression chamber 16 in order to protect the blade 15 from damage.

As described above, the coefficient of thermal expansion of the blade 15 material is greater than the coefficient of thermal expansion of the roller 11 material. Thus, the clearance between the blade 15 and the spiral groove 14 of the roller is small at high temperatures and large at low temperatures. Thus, the above operating conditions are obtained.

In addition, the coefficient of thermal expansion of the roller 11 material is larger than that of the cylinder 5 material. Therefore, the clearance between the roller 11 and the cylinder 5 is small at high temperature, and large at low temperature. Thus, the above operating conditions are obtained. Moreover, since the roller 11 is formed of aluminum alloy, it has a lighter weight than the conventional roller formed of cast iron. Thus, vibration and noise can be suppressed during operation.

The sliding portion between the roller 11 and the crankshaft 9 has nothing to do with the compression performance of the compression chamber 16. Thus, the same clearance is maintained between the roller 11 and the crankshaft 9 regardless of the temperature. The clearance between them is particularly important because the roller 11 and the crankshaft 9 are components to which a large force is applied by the gas load.

However, the roller 11 is formed of aluminum alloy, and the crankshaft 9 is formed of iron-based material. Because they are made of completely different materials, there is a big difference in the coefficient of thermal expansion between them. Because of the large change in clearance, this can lead to flaking problems.

The present invention solves this problem by employing a sleeve 12 formed of the same material as the crankshaft and arranging the sleeve only in an area in which the roller and the crankshaft are in sliding contact.

The sleeve 12 is formed of an iron-based material which is the same material as the crankshaft 9, and is forcibly inserted into contact with the inner circumferential wall of the eccentric hole portion 11a. Thus, the clearance between the roller 11 and the crankshaft 9 is constant regardless of the temperature.

The roller 11 formed of an aluminum alloy may be coated with a radio plating layer formed of Ni in order to improve wear resistance characteristics.

In particular, the aluminum alloy of the roller 11 is an Al-Si alloy containing 3% by weight or more of Si (silicon), the precipitation rate of the initial crystallized Si is 20% or less, and the particle size of the initial crystallized Si particles is 30 micrometers or less (average particle diameter measured as the diameter of a corresponding circle), and the strength of a compound is HRB60 or more.

As shown in Fig. 3A, the transceiver plating layer M on the surface of the roller 11 made of aluminum alloy is formed on the substitution plating layer t. This layer has a film hardness of Hmv500 or more, and is located opposite to the Oldhams mechanism 13 in a manner formed at least inside the spiral groove 14 and having a layer thickness of 5 to 30 탆. The film thickness error is within ± 20% of the average thickness.

In particular, the transceiver plating layer is an alloy plating layer or dispersion (composite) plating layer 1 formed on the substitution plating layer t provided on the surface of the roller 11 and containing 80% by weight or more of Ni.

Optionally, as shown in FIG. 3B. A two-layer radio plating layer MA may be provided, which is a base plating layer and an upper plating layer. In this case, the base plating layer ma is formed in the substitution plating layer t provided on the surface of the aluminum alloy base material 11, and contains 80 wt% or more of Ni.

The dust-free plating layer may be formed of three kinds of alloy materials based on (Ni-P), (Ni-B) or (Ni-P-B).

Further, a plating layer of hard particles of SiN, SiC, and BN dispersed in 20 wt% or less with a matrix formed of three kinds of alloying materials of (Ni-P), (Ni-B) or (Ni-PB) or 20 wt% or less. It can be made into one of the plating layers of self-lubricating materials such as C, PTFE, mica and MoS ₂ dispersed at or below weight percent.

The above-mentioned two-layer radio plating layer MA includes a base plating layer formed of Ni-P and the following plating layers: a layer formed of an alloy material of Ni-B or Ni-PB; A hard particle layer of SiN, SiC, and BN dispersed at 20% by weight or less; And one of layers formed of self-lubricating materials such as C, PTFE, mica and MoS ₂ dispersed at 20 wt% or less.

With respect to the two-layered electroless plating layer MA, the thickness ratio of the upper layer mb and the lower layer ma is most preferably in the range of 9/1 to 2/1.

4 and 5 are diagrams showing the amount of wear of the helical groove 14 with respect to operating time. The data in the table were obtained from the durability test of the rollers of different materials. The properties of Example 1, Example 2 and Comparative Example 1 are shown in Table 1.

Example 1 Example 2 Comparative Example 1 Refrigerant R410A R410A R410A slush Ester oil Ester oil Ester oil roller Surface treatment Ni-P-B / Ni-P Ni-B Thickness 15/5 20 - Base material Al-10% Si-2Cu Al-10% Si-2Cu Al-10% Si-2Cu blade PTFE (10% GF) PTFE (10% GF) PTFE (10% GF) Oldham's Ring Al casting Small bond Small bond

In Table 1, "PTFE (10% GF)" refers to tetraethylene fluoride with 10% glass fiber added as reinforcing agent. "Al casting" corresponds to JIS ACSC, and "small alloy" corresponds to JIS SMF4.

In Examples 1 and 2, the surface of the roller 11 is covered with a plating layer formed by the radioless plating method, and the wear amount of the roller 11 and the Oldhams ring 13 is noticeable after the initial sliding wear occurs at the beginning of operation. It didn't increase. Thus, in this embodiment, stable operation could be performed for a long time.

On the contrary, in comparison 1, the surface of the roller 11 was not provided with the electroless plating layer and the amount of wear of the roller 11 and the Oldhams ring 13 continuously increased with the operation time. Stable operation was not possible in a short time.

The above structure can lead to the following points;

(1) Machining (cutting property = durability) can be improved by optimally determining the structure of aluminum alloy (ratio of initial crystallized Si and precipitated Si particle diameter) serving as the base material of the roller 11.

(2) Uniform film thickness dispersion is obtained by forming a radioless plating layer having a small coefficient of friction on the surface of the roller 11, which can bring about cost reduction by minimizing required processing.

(3) Even if the base material of the roller 11 is aluminum alloy, both the wear of the roller 11 itself and the wear of the member in sliding contact with the roller are minimized. This is because the radio plating layer formed on the surface of the roller 11 is very hard and has a small coefficient of friction.

Because of the rigidity, the raw material of the blade 15 and the additives added to the raw material to reinforce the blade 15 can be selected very freely. Because of the stiffness and small coefficient of friction, the Oldhams mechanism 13 for turning components such as the roller 11 can be formed of a light weight aluminum alloy. Thus, the performance of the compressor can be enhanced.

(4) The radio plating layer on the surface of the roller 11 has a two-layer structure, and the base plating layer of Ni-P has a high resistance to impact. Thus, the top layer of the transceiver plating layer is prevented from cracking.

(5) Because of the advantages of (3) and (4) above, not only the environment in which HCFC (typically R22) and mineral oil are used but also in the environment of HFC refrigerants (R410A, which typically does not contain chlorine atoms and does not reduce wear resistance) Reliability is obtained and synthetic fluids (ie ester oils and polyether oils) are used.

Hereinafter, the selection of the material of the blade 15 will be described.

The blade 15 is formed of a so-called super engineering plastic material (hereinafter referred to as "SEP material") of a thermoplastic resin having improved heat resistance, oil resistance, and cooling property, so that adverse effects caused by thermal expansion and pressure conditions are minimized. Can be suppressed, thus improving compression characteristics and reliability.

Described is a method according to the invention.

To confirm the advantage of manufacturing the blade 15 from SEP material. The blade was molded by injection molding using PEEK resin material (trade name Victrex 450G from Sumitomo Chemical Co., Ltd.) and the compression performance was measured according to the use of the blade. For comparison, another blade was molded using a PTFE resin material (7-J from Dupont-Mitsui Fluorochemicals Co., Ltd.) with a density of 2.1 g / cm 3, and the compressive performance was measured under the same conditions.

To explain the elastic modulus and thermal expansion effect of the material. The coefficient of performance (COP) of the compressor was measured immediately after assembly of the compressor and after 100 hours of operation under temperature conditions of 80 ° C, 100 ° C and 120 ° C. The clearance between the blade 15 and the helical groove 14 was determined in consideration of the thermal expansion generated when the temperature of the sealed case 1 was the highest (120 ° C.).

Table 2 shows the test results of the above embodiment, and the test results show that the performance coefficient is 100% after assembling the compressor of the embodiment and when the temperature is 80 ° C. The wear of the blade measured after 100 hours of operation is also shown in the table.

blade Example Comparative example Temperature 80 ℃ 100 ℃ 120 ℃ 80 ℃ 100 ℃ 120 ℃ Performance factor measured immediately after assembly 97 99 100 75 89 100 Performance factor measured after 100 hours of use 105 106 108 85 87 88 Abrasion after 100 hours of use 3 μm 3 μm 4㎛ 25 μm 40 μm 55 μm

As shown in Table 2, the blade 15 formed of the PEEK resin material according to the embodiment does not show any significant difference between the performance coefficient measured immediately after assembly and the performance coefficient measured after 100 hours of operation. The improvement in performance due to the fit between the sliding surfaces was observed after time. In addition, the temperature of the case did not make a big difference in performance.

For conventional blades formed of PTFE resin, it was observed that the temperature of the case caused a large difference in compression performance measured immediately after assembly. Performance improvements were observed in compression performance measured after 100 hours of operation, due to the fixing between sliding surfaces, such as the case where PEEK resin was used. In addition, the compressive performance was observed to decrease with increasing case temperature.

The above results indicate that the amount of wear is large in conventional PTFE resins and small in PEEK resins, as can be seen from the blade wear data. As the case temperature rises, the amount of wear on the blade increases, which reduces the compression performance.

In the case of the conventional PTFE resin material, the coefficient of thermal expansion is large. When the initial clearance is determined by the clearance given at the upper limit of the temperature zone in which the compressor is used, this clearance can be unnecessarily large when the temperature of the compressor is relatively low. As a result, compression performance begins to decrease. At high temperatures, not only the ductility of the PTFE resin material but also its elastic modulus decreases. In this case, deformation of the blade shown in Fig. 14 can easily occur, and the amount of wear is also increased.

If the blade is formed by PEEK resin material and manufactured by injection molding in a manner having an uneven pitch according to the spiral groove 14, the movement of the blade relative to the spiral groove is not prevented or contracted. Compared with PTFE resin, PEEK resin does not expand significantly by heat. Thus, although the initial clearance is determined by the clearance presented at the upper limit of the temperature zone in which the compressor is used, the clearance at low temperatures is adequate. Therefore, the compression performance does not decrease. Moreover, the compressive performance can be maintained in large temperature zones because the elastic modulus is high at high temperatures.

As described above, the use of the SEP material for the blade satisfies the environmental conditions (such as heat resistance, oil resistance and refrigerant resistance) in which the compressor can be used. In addition, the SEP material has an elastic modulus of 4 to 10 times larger than that of the fluoroplastic material and a coefficient of linear expansion of 1/3 or less than that of the fluoroplastic material. Thus, the use of these materials has the same advantages.

In order to smooth the movement of the blade 15 relative to the helical groove, a hollow zone is provided inside the blade 15. Even if SEP material is used, this structure has the advantage that it remains unchanged.

As shown in Figs. 6 and 7, in the spiral blade type compressor, the roller 11A is disposed at an eccentric position inside the cylinder 5A and rotates together with the cylinder 5A. The hollow section 15x in the blade 15A is formed to extend from the inlet port A (low pressure end) to the outlet port (high pressure end). The hollow section 15x is sealed at the outlet so that the compression chamber does not communicate.

PEEK resin material (trade name Victrex 450G from Sumitomo Chemical Co., Ltd.) is used as the material of the blade 15A. In the comparative example, the blade did not have a hollow zone made by the use of the same material, and the compressive performance was measured under the same conditions.

When the compression performance was measured, the temperature was kept low (room temperature), and the compressor was run at low speed so that the liquid refrigerant was sucked into the compressor. The measurement results are shown in Table 3, and as shown in the comparative example, the coefficient of performance (COP) of the blade formed of PEEK resin material and not having a hollow zone is represented as 100. The amount of blade wear after measurement is also shown in the table.

blade Example Comparative example PEEK resin PEEK resin Hollow Zone Exist No hollow zone Compressor Performance Factor 115 100 Wear 3 μm 25 μm

As shown in Table 3, the blade formed of the PEEK resin material according to the comparative example, without a hollow has a weak compression performance and a large blade wear (25㎛). This is due to the fact that an increased load is imposed on the blade by the fluid compression of the refrigerant.

The blade 15A according to the embodiment also has a hollow section formed of PEEK resin material and extending from the low pressure end to the high pressure end. However, despite the same material, the compression performance of the compressor employing this blade was as high as 115%. In addition, the wear amount of the blade was also small (3 µm). This is due to the hollow zone 15x acting as a liquid reservoir for temporarily storing the liquefied refrigerant to suppress fluid compression.

However, if the shape of the hollow zone 15x is applied to a blade made of soft fluoroplastic material with a size to overcome the fluid compression, a low pressure refrigerant is introduced into the hollow zone 15x and a high pressure difference is applied to the high pressure of the blade 15A. Is introduced at the end. Due to this pressure difference, the sealing property is lowered, and the compression performance is lowered under stable operating conditions.

As described above, the blade 15A is formed of SEP material having a small coefficient of thermal expansion and a large modulus of elasticity at high temperature, and a hollow section 15x is provided in the blade 15A. By using such a blade 15A, the compressor can maintain high reliability even under high compression performance, variable operating conditions, and a temporary situation in which a liquid refrigerant is sucked in. The hollow section 15x of the blade 15A is easily formed by gas support molding.

8A-8C show an example of a blade molded by a gas assisted molding method (Asahi Chemical Industry Co., Ltd .: AGI method).

8A shows a two-gate mold 35 in which gas is injected from the nozzle 36 of the injection molding apparatus. Reference numeral 37 denotes a core, reference numeral 38 denotes a cylinder, reference numeral 39 denotes a screw, reference numeral 40 denotes a gas injection portion, and reference numeral 15A denotes a blade.

FIG. 8B shows a molding method using the one-gate mold 35A injected from the end of the blade in a gas-fixed mold. The other part of the injection molding machine is similar to the injection machine.

8C shows a molding method using a one-gate mold 35A injected from the end of the blade in a gas-movable mold 40. The other part of the injection molding machine is similar to the injection machine.

As mentioned above, according to the gas support method, the unit is connected to the normal form of the injection molding machine. The high pressure nitrogen gas is injected into the shaping nozzle 38 and the molds 35-35B as shown in FIGS. 8A-8B under pressure.

In order to explain the dimensional accuracy influenced by the resin material used in the gas support method, the blade 15A is actively produced by the gas support method described in Fig. 8B and the resin is supplied from the end of the blade.

PEI resin material (Ultem 1000 from GE Plastics Co., Ltd.) was used as the material, and fluoroplastic (PFA340-J from Dupont-Mitsui Fluorochemicals Co., Ltd.) was used as a comparative example. In order to compare them, the blade dimensions were measured at nine places, and the gate portion of the blade is represented by No. 1, and the edge of the blade opposite to the gate portion is represented by No. 9. The blade shrink mark (ie, the dimensional difference at the center of the cross section of the blade) is shown in FIG. 9.

As shown in Fig. 9, the blade shrinkage mark is hardly shown for the case in which the PEI resin material is used, but is shown at the end of the blade for the case in which the PFA resin material is used.

10A shows the occurrence of blade shrinkage marks. As shown, the surface layer 41 of the blade 51 is cooled and cured for a predetermined time after the blade 15 is formed. However, at this time, the interior 42 of the blade 51 remains in a molten state.

After a predetermined time, the interior 42 of the blade 51 is cooled and cured. Thereafter, the volume of the blade is reduced so that the surface of the blade is attracted to the core portion to obtain a blade shrinkage mark y.

The blade shrinkage mark is marked in the case of fluoroplastic material because it has a large mold shrinkage factor. All surfaces of the blade 15A are sealing surfaces. The gate into which the resin is injected should not be provided at the intermediate position of the helical structure because the gate is provided at a position that adversely affects the smoothness of the surface. This means that the gate must be located at the end of the blade. However, this structure has a problem that the resin flows a long distance and the pressure for injecting the resin is not sufficiently transmitted to the end. Thus, the blade shrinkage mark is displayed at the position opposite the gate.

Conversely, the high pressure gas is injected into the blade 15A according to the gas support molding. Since the blade 15A is cooled and held by the pressurized gas inside the blade, the blade shrinkage mark is suppressed. In addition, the pressure supplied to the helical structure is uniform at any position to enable low pressure molding.

Since PFA resin has low fluidity (ie high viscosity), the flow resistance of gas is high. The hollow zone 15n (hollow zone shown in Fig. 11B) at the No. 9 measuring position located at the blade end is the hollow zone 15m at the No.1 measuring position located at the gas inlet (shown in Fig. 11A). Hollow zone).

As shown in the comparative example shown in FIG. 9, the shrinkage mark at the end of the blade 15 is larger. In addition, since the PFA resin material has a larger mold shrinkage mark than the PEI resin material, the shrinkage mark is very large at the blade end position where the hollow area is small.

Since the PEI resin has good flowability, as shown in Figs. 12A and 12B, the hollow zone 15x does not show a large dimensional difference even when measured at different positions. PEI resins are just examples, but some types of SEP materials have improved fluidity. Further, the mold shrinkage factor of the SEP material is less than 1/2 of the fluororesin material, so that the SEP material increases the dimensional accuracy when selected as the material of the blade 15A manufactured by the gas assisted molding method. Moreover, the use of the SEP material ensures the improvement of the sealing property and can realize high compression performance.

In addition, the hollow zone 15x may be formed in a manner extending from the low pressure suction end to the high pressure discharge end. In addition, the gas assisted molding method increases the cooling rate measured in the cross-sectional area and shortens the molding cycle. As a result, production yield is improved and productivity is increased.

Mixtures of PEEK and PES resins may be present, and SEP materials may be mixed with other types of SEP materials as long as their original properties are not adversely affected. Also known composite materials comprising additives can be added to improve the sliding properties. Examples of additives are inorganic fibers and solid lubricants.

More specifically, the inorganic fibers are glass fibers, carbon fibers (PAN, pitch), graphite fibers, aluminum fibers, wollastonite. Potassium titanite whiskers, carbon whiskers, silicon carbide whiskers and the like. Examples of solid lubricants include disulfide, graphite, carbon, boron, nitrogen, bronze, fluororesins and the like.

The tip seal employed in the scroll compressor and the tip seal used in the currently proposed 3D scroll compressor have a function similar to that of the blade of the spiral blade compressor described above.

Unlike the blades of a helical bladed compressor, these structures do not enter or exit a helical groove. However, they are sealing members and are manufactured to slide and require large lengths. Similar to the helical blades described above, high dimensional accuracy is required. Therefore, the same advantages will be obtained if they are formed of SEP material and manufactured by the gas support method.

Claims (14)

In the fluid compressor comprising a spiral blade type compression mechanism, cylinder; A rotating member disposed inside the cylinder; And a spiral blade sandwiched between the rotating member and the cylinder, The blade, the rotating member and the cylinder is a fluid compressor, characterized in that formed of a material having a coefficient of thermal expansion that satisfies the relationship of the blades> rotating member> cylinder. The method of claim 1, The blade is formed of a composite resin material, the rotating member is formed of an aluminum-based material, the cylinder is characterized in that the fluid compressor is formed of an iron-based material In the fluid compressor comprising a spiral blade type compression mechanism, cylinder; A rotating member disposed inside the cylinder; And a spiral blade sandwiched between the rotating member and the cylinder, And the rotating member is formed of an aluminum alloy material. The method of claim 3, wherein And the rotating member is a roller having an eccentric hole, and a sleeve formed of an iron-based material is provided on the inner circumferential wall of the eccentric hole. The method of claim 3, wherein The aluminum alloy material of the rotating member is an Al-Si alloy containing 3% by weight or more of Si (silicon), and the precipitation rate of the initial crystallized Si is 20% or less, and the average particle diameter of the initial crystallized Si (corresponding to And an average particle diameter measured as the diameter of the circle) is 30 µm or less, and the hardness of the compound is HRB60 or more. The method of claim 3, wherein And the rotating member is a roller having a surface coated with a radio plating layer formed of nickel. The method of claim 6, The transceiver plating layer has a film hardness of Hmv 500 or more, and is formed of a substitution plating layer having a thickness of 5 to 30 μm at least inside the spiral groove and having a sliding portion facing the Oldhams mechanism. The transceiver plating layer is a fluid compressor, characterized in that the film thickness error within ± 20% of the average thickness. The method of claim 6, The transceiver plating layer is formed of nickel and is located around the circumferential surface of the rotating member and is one of one or two layer structures, The transceiver plating layer is a fluid compressor, characterized in that formed of an alloying material of Ni-P, Ni-P-B containing Ni of 80% by weight. The method of claim 8, A radio plating coating is provided around the circumferential surface of the rotating member, The radio plating coating employs the radio plating layer as a matrix, and is a plating layer of hard particles of SiN, SiC, and BN dispersed at 20% by weight or less; And a plated layer of self-lubricating material such as C, PTFE, mica and MoS ₂ dispersed at 20% or less by weight. The method of claim 8, The two-layered electroless plating layer may include a base plating layer formed of Ni-P and an alloy material of either Ni-B or Ni-PB; A hard particle layer of SiN, SiC, and BN dispersed at 20% by weight or less; And an upper plating layer continuously formed on the base plating layer, including one of plating layers of self-lubricating material such as C, PTFE, mica, and MoS ₂ dispersed at 20% by weight or less. The method of claim 8, The radio plating layer of the two-layer structure is provided around the circumferential surface of the rotating member, wherein the thickness ratio of the upper plating layer and the base plating layer is in the range of 9/1 to 2/1. In the fluid compressor comprising a spiral blade type compression mechanism, cylinder; A rotating member disposed inside the cylinder; And a spiral blade sandwiched between the rotating member and the cylinder, The blade is a PEEK (polyether ether ketone) resin material, PES (polyether sulfone) resin material, PEI (polyether imide) resin material, PAI (polyamide imide) resin material, TPI (thermoplastic polyimide) resin material And a material selected from the group consisting of an LCP (liquid crystal polymer) resin material and a PPS (polyphenylene sulfide) resin material. The method of claim 12, And the blade has a hollow section on the inside. The method of claim 13, The blade having a hollow zone therein is molded by injection molding, and the injection molding is performed by a gas support method in which high pressure nitrogen gas is blown from a nozzle or a mold.