JPH08105391A - Tip seal and scroll compressor - Google Patents

Abstract

PURPOSE: To give the wear resistance by mixing the linear type polyphenylene sulfide resin, he carbon fiber and the poly tetra fluoro ethylene at the prescribed ratio to form a tip seal. CONSTITUTION: Tip seals 21, 31 provided on the tip of spiral blades 22,32 of fixed and movable scroll members 2, 3 of a scroll compressor are formed by appropriately using the composition consisting of 20-90% linear type polyphenylene sulfide resin (linear type PPS), 5-40% carbon fiber (CF) and 5-40% poly tetra fluoro ethylene (PTFE). The linear type PPS includes poly phenylene sulfide resin having the straight chain molecular structure and the pitch type graphite CF which is obtained through the heat treatment of the carbon fiber manufactured of petroleum or coal pitch at high temperature around 2100 deg.C is preferably used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor tip seal and a scroll compressor used in an air conditioner such as an air conditioner.

[0002]

2. Description of the Related Art A scroll compressor is composed of two scroll members each having an end plate and spiral blades.
Both scroll members are in a state in which their respective spiral blades are engaged with each other. Then, the scroll compressor maintains the meshing of both scroll members,
When one revolves around the other, gas is sucked, compressed, and discharged using the space formed by the spiral blades of both as the working chamber (see FIG. 1 described later).

And, the scroll compressor is
A seal member for maintaining the sealing property of the working chamber is provided at the tip of the spiral blade. Conventionally, engineering plastic or the like has been used as the material of the seal member. Examples of the above engineering plastics include PEEK (polyether ether ketone),
A resin obtained by adding CF (carbon fiber), PTFE (polytetrafluoroethylene) or the like to PPS (polyphenylene sulfide resin) can be mentioned.

In addition to the above resins, Japanese Patent Laid-Open No. 62-2
In Japanese Patent No. 23488, a resin obtained by adding a tetrafluoroethylene resin or the like to an aromatic polyether ketone resin or the like, and in Japanese Patent Application Laid-Open No. 3-273083 is a resin obtained by mixing a fluorocarbon or the like with a polyphenylene sulfide resin,
Each has been proposed as a material for the above sealing material.

[0005]

However, the sealing material made of the above-mentioned conventional material may not be suitable for use in a scroll compressor having a high load and a high rotation, which is used, for example, in a vehicle air conditioner. That is, in the scroll compressor, the load on the seal material is large, and the seal material made of the above resin may be worn in a short time. As the seal material wears, the sealability at the contact surface between the seal material and each scroll member and the like deteriorates, and the sealability of the working chamber deteriorates. As a result, the gas compression efficiency of the scroll compressor may decrease in a short time.

In view of the above problems, the present invention is intended to provide a scroll compressor tip seal and a scroll compressor having excellent wear resistance.

[0007]

The present invention relates to a linear polyphenylene sulfide resin (linear PPS, hereinafter the same) 20 to
90%, carbon fiber (CF, same below) 5
The tip seal for a scroll compressor is characterized by being formed by mixing 40% and 5 to 40% of polytetrafluoroethylene (PTFE, the same applies hereinafter) and molding.

The linear PPS is a polyphenylene sulfide resin having a linear molecular structure. The tip seal is made of the linear PPS 20
˜90% is preferable. The above content is 2
If it is less than 0%, the flowability of the molten resin may deteriorate. On the other hand, when it is more than 90%, C
The amount of F and PTFE added becomes small, and the effect of abrasion resistance may not be sufficiently obtained. The lower limit of the content range is more preferably 50%.

The tip seal preferably contains 5 to 40% CF. If the content is less than 5%, the wear resistance of the tip seal may not be expected to improve. On the other hand, when the content is more than 40%, the flowability of the molten resin deteriorates. For this reason, when molding the tip seal, there is a possibility that only a brittle molded product can be obtained. It is more preferable that the lower limit of the content is 5% and the upper limit is 25%.

It is particularly desirable to use pitch-based graphite CF among various CFs such as PAN-based CF and carbon-based CF. The pitch-based graphite CF is carbon fiber produced from petroleum or coal pitch,
It can be obtained by heat treatment at a high temperature of about 2100 ° C. Further, the pitch-based graphite CF has a crystal structure similar to a diamond structure in which bonds between carbon atoms are covalent bonds.

The pitch-based graphite CF is another CF
The wear resistance of the tip seal is further improved as compared with carbonaceous CF (see FIG. 5 described later). Further, the pitch-based graphite CF has an advantage that the price is lower than that of the PAN-based CF.

The tip seal is made of PTFE of 5 to 40
% Content is preferable. If the content is less than 5%, it may not be possible to expect improvement in wear resistance. On the other hand, when the content is more than 40%, the flowability of the resin deteriorates. For this reason, when molding the chip seal, there is a risk that only extremely brittle molded products may be selected. The lower limit of the above range is 5
%, And the upper limit is more preferably 25%.

When the pitch-based graphite CF is used, it is not limited to the above-mentioned linear PPS but other types of PP.
S can be used. As other types of PPS, cross-linked PPS, semi-cross-linked PPS, etc. described later can be used. The pitch-based graphite CF can greatly improve the wear resistance of the tip seal as compared with other types of CF, as shown in Examples described later. Therefore,
For tip seals made of PPS other than linear type,
Sufficient wear resistance can be imparted.

Next, the scroll compressor of the present invention will be described. That is, the present invention has a fixed scroll member having a spiral blade and an end plate for supporting the spiral blade, and a spiral scroll and an end plate for supporting the spiral blade, facing the fixed scroll member. Is arranged,
In addition, it is formed between a movable scroll member configured to perform an orbital motion while preventing rotation and a fixed scroll member and a movable scroll member, and the orbital motion of the movable scroll member causes the spiral blade to move. A plurality of working chambers configured so that the volume gradually decreases from the outer peripheral side toward the central axis, a discharge pressure chamber into which the high-pressure fluid discharged from the center side of the plurality of working chambers flows, and a plurality of the working chambers In a scroll compressor having a suction pressure chamber for introducing low-pressure fluid to the outer peripheral side of the chamber and having tip seals arranged at the tips of the respective spiral blades, the tip seals include linear polyphenylene sulfide resin 20 to 90%, carbon fiber 5-40%,
A scroll compressor is characterized by comprising polytetrafluoroethylene in an amount of 5 to 40%.

A seal groove is provided at the tip of the spiral blade, and a preformed chip seal is arranged in the seal groove. The tip seal has a spiral shape, and its molding is performed by injection molding.

Further, in the above tip seal, when the fixed scroll member and the movable scroll member are engaged with each other, the tip seal provided on the movable scroll member is the fixed scroll member, while the tip seal provided on the fixed scroll member is It abuts against the movable scroll member. The working chamber is a space formed by the spiral blade and the tip seal in the movable scroll member and the fixed scroll member. The tip seal retains the sealing property of the working chamber. Further, since the tip seal has excellent wear resistance as described above, it also has an excellent sealing property in the working chamber of the scroll compressor.

Further, the tip seal described above can be used in the scroll compressor described above. That is, a predetermined amount of linear PPS and pitch-based graphite CF and P
To improve the sealability of the working chamber of a scroll compressor by using a tip seal formed by mixing TFE and a tip seal formed by mixing PPS, pitch graphite CF and PTFE. You can

[0018]

FUNCTION AND EFFECT The tip seal of the present invention is formed by mixing linear PPS, CF and PTFE in specific amounts. Here, PPS can be classified into three types depending on the cross-linking state of the molecule. That is, crosslinked PPS, semi-crosslinked PPS, and linear PPS. In addition, linear type P
The tip seal containing PS has a much smaller amount of wear than the case of using other PPS. Further, by adding the above-mentioned specific amounts of CF and PTFE, it is possible to impart more excellent wear resistance to the chip seal.

Further, the scroll compressor of the present invention uses the tip seal excellent in wear resistance as described above. In the scroll compressor, when the movable scroll member revolves with respect to the fixed scroll member, the working chamber formed between the two sucks, compresses and discharges air and the like. Therefore, the tip seal receives a frictional force as the scroll compressor operates.

The working chamber is formed between the movable scroll member and the fixed scroll member, and the tip seal secures the sealing property required for the working chamber. Since the working chamber is a part that sucks, compresses, and discharges air and the like in the scroll compressor, the sealing property of the working chamber greatly affects the quality of the performance of the scroll compressor.

In the scroll compressor according to the present invention, since the tip seal has high wear resistance, the sealability of the working chamber is hardly deteriorated. Therefore, the gas compression efficiency of the scroll compressor can be kept high for a long period of time.

As described above, according to the present invention, it is possible to provide a scroll seal tip seal and a scroll compressor having excellent wear resistance.

[0023]

【Example】

Embodiment 1 A tip seal and a scroll compressor according to an embodiment of the present invention will be described with reference to FIGS. In this example, linear PPS 80%, CF 15%, PTFE
5% and 5% are mixed to form a chip seal. It should be noted that pitch-based graphite CF is used as the CF.

In the above-mentioned molding, first, the above-mentioned predetermined amount of linear PPS is melted. Next, CF is mixed with the molten linear PPS. After that, PTFE is added and kneaded to obtain a mixed material. After pelletizing the mixed material, the pellet is put into an injection molding machine, and a chip seal having a desired shape is obtained by injection molding. In addition,
The tip seal has a spiral shape (see FIG. 2).

Next, a scroll compressor using the above tip seal will be described. The scroll compressor of this example is applied to an automobile air conditioner. As shown in FIGS. 1 to 3, the scroll compressor 1 according to the present embodiment includes a spiral blade 22 and the spiral blade 22.
It has the fixed scroll member 2 which has the end plate 20 which supports. Further, it has a spiral blade 32 and an end plate 30 for supporting the spiral blade 32, is arranged so as to face the fixed scroll member 2, and is configured to perform an orbital motion while preventing rotation. It has a movable scroll member 3.

Further, the volume formed between the fixed scroll member 2 and the movable scroll member 3 is gradually reduced from the outer peripheral side of the spiral blade 32 toward the central axis by the revolving motion of the movable scroll member 3. A plurality of working chambers 40 configured to operate. Further, it has a discharge pressure chamber 42 into which the high pressure fluid discharged from the center side of the plurality of working chambers 40 flows, and a suction pressure chamber 41 into which the low pressure fluid is introduced to the outer peripheral side of the plurality of working chambers 40. The tip seals 21 and 31 are provided at the tips of the spiral blades 22 and 32 (FIGS. 2 to 4).

Further, the above will be described in detail. FIG.
In the above, reference numeral 10 is a rotary shaft. The rotary shaft 10 is connected to the rotation system of the automobile engine via an electromagnetic clutch (not shown) at the left end of the same figure, and is rotated by receiving the driving force of the automobile engine.

Reference numeral 11 is a crank portion. The crank portion 11 is a bearing support portion 101 of the rotary shaft 10.
Is integrally provided on the rotary shaft 10 and
It is provided so as to be eccentric from the shaft center of. The shape is a pin shape.

In FIG. 1, reference numeral 12 is a front housing, which is provided with bearings 13 and 14 to rotate the rotary shaft 1.
0 is rotatably supported. Reference numeral 16 is a counterweight that is rotatably fitted to the crank portion 11.

The movable scroll member 3 is composed of an involute-shaped spiral blade 32 and an end plate 30 having substantially 2.4 turns. Shaft 3 of the end plate 30
9 is arranged so as to be eccentric by a predetermined amount with respect to the axis of the rotary shaft 10. The shaft portion 39 is rotatably supported by the needle bearing 162 of the counterweight 16. The needle bearing 162 is press-fitted and fixed to the inner peripheral surface of the circular hole 161 of the counterweight 16.

Further, the end plate 3 of the movable scroll member 3 is
0 and the opening end surface 121 of the front housing 12 are provided with a rotation preventing mechanism including a combination of a plurality of spherical bodies 17 and circular grooves, and this mechanism prevents the movable scroll member 3 from rotating. It is like this.

The fixed scroll member 2 is integrally formed with a spiral blade 22 and an end plate 20 which are formed in an involute shape having substantially 2.4 turns. Besides, the fixed scroll member 2 integrally has a casing portion 27 having a suction port 28 and a discharge port 29. A suction pressure chamber 41 that is in constant communication with the suction port 28 is formed on the inner peripheral side of the casing portion 27. In FIG. 1, reference numeral 19 is a rear housing,
The front housing 12 and the fixed scroll member 2 are integrally tightened and fixed by bolts (not shown).

As shown in FIGS. 2 and 3, in the movable scroll member 3, a seal groove 320 is provided at the tip of the spiral blade 32, and the shape of the movable scroll member 3 with respect to the seal groove 320. A chip seal 31 formed according to the above is provided. Although illustration is omitted, the fixed scroll member 2 is also fixed with the tip seal 21 similarly to the movable scroll member 3 described above.

As shown in FIGS. 1 and 4, the fixed scroll member 2 and the movable scroll member 3 are assembled so that their spiral blades 22 and 32 are meshed with each other. The tip seals 21 and 31 of both are in contact with the surface of the other side. The scroll compressor 1
Relies on the movable scroll member 3 to revolve with respect to the fixed scroll member 2, thereby sucking, compressing, and discharging air. In the series of these operations, the tip seals 21, 31 seal the working chamber 40 and the like. Has a role to hold. The fixed scroll member 2 is made of aluminum, and the movable scroll member 3 is made of nickel-phosphorus-plated aluminum.

The operational effects of the tip seals 21 and 31 and the scroll compressor 1 of this embodiment will be described below.
The tip seals 21 and 31 of this example contain a predetermined amount of linear PPS, pitch-based graphite CF, and PTFE. Therefore, it has excellent wear resistance as shown in Examples described later. The scroll compressor 1 of this example uses the tip seals 21 and 31 having excellent wear resistance as described above.

Therefore, the scroll compressor 1 of this example
Since the chip seals 21 and 31 are less likely to wear, the sealability of the working chamber 40 hardly deteriorates during use. Therefore, the gas compression efficiency of the scroll compressor 1 can be kept high for a long period of time.

Therefore, according to this example, it is possible to provide a scroll compressor tip seal having excellent wear resistance and a scroll compressor having excellent working chamber sealability.

Example 2 In this example, the wear resistance of Samples 1 to 6 according to the tip seal of the present invention will be described together with Comparative Examples C1 and C2. First, the components of Samples 1 to 6, C1 and C2 according to the present invention will be described. As shown in Table 1, samples 1 to 6, C1,
C2 is a linear PPS or semi-crosslinked PP of a predetermined amount.
It contains S, crosslinked PPS, pitch-based graphite CF, pitch-based carbon CF, and powdered PTFE. For example, as shown in Table 1, samples 1 to 3 have a predetermined amount of linear PPS.
And pitch-based graphite CF and PTFE.

Next, each component shown in Table 1 will be described. First, the semi-crosslinked and crosslinked PPS represent PPS resins having a crosslinked structure. In addition, semi-crosslinked PPS
Has a crosslinked structure in about 50% of the total molecular structure, and has a linear structure in the other.

The pitch-based carbonaceous CF is a CF having a crystal structure similar to graphite in which the bond between carbon atoms is an intermolecular force and produced from petroleum and coal pitch. Samples 1 to 1 made of these materials
In molding 6, C1 and C2, the same molding method as in Example 1 is used.

Next, a method for measuring the wear resistance of the above samples 1 to 6, C1 and C2 will be described. In the above measurement, first, the height dimension of the test piece before the test is measured with a micrometer with an accuracy of 0.001 mm. After that, a friction test is conducted using a Suzuki type friction tester. After the test is completed, the height dimension of the test piece is measured again, and the difference in the height dimension is taken as the wear amount.

In the above measurement, the surface pressure is 30 k
gf / cm ² , speed is 2 m / s, counterpart material is aluminum (AC8C-T6), and each sample 1 to 6, C1, C2 and its counterpart material are left in oil for 2 hours. After that,
The wear amounts of the samples 1 to 6, C1 and C2 are measured twice.
In the above measurement, the test piece is left in the oil in order to perform the test in a state close to the environment actually used as the tip seal.

As shown in Table 1, according to the above measurement results, the samples 1 to 6 according to the present invention are all comparative examples C.
It can be seen that the amount of wear is smaller than that of C1 and C2 and the wear resistance is excellent. Further, all of Samples 3, 4, and 5 contain pitch-based graphite CF, but the types of PPS are different.
Among these samples, since the sample 3 containing the linear PPS has the smallest wear amount, it can be seen that the chip seal containing the linear PPS has excellent wear resistance.

Samples 3 and 6 are all linear PPS.
It contains. Samples 4 and C1 are semi-crosslinked PP
S, Sample 5, and C2 each contain crosslinked PPS. From a comparison between these samples, it can be seen that the tip seal containing the pitch-based graphite CF has excellent wear resistance.

[0045]

[Table 1]

Example 3 In this example, samples 3 to 5, C1 and C2 of Example 2 are
The relationship between the types of PPS and CF contained and the amount of wear will be described with reference to FIG. The horizontal axis of FIG. 5 represents the type of PPS. “Crosslinking” is the measurement result of a sample containing 80% of crosslinked PPS. Similarly, "semi-crosslinked" means 80% of semi-crosslinked PPS, and "linear type" means linear type PPS.
It is a measurement result of the sample containing 80%. The vertical axis represents the amount of wear measured above.

The solid line shows the wear amount of the sample containing 15% of pitch-based graphite CF, and the dotted line shows the wear amount of the sample containing 15% of pitch-based carbonaceous CF. The curve in FIG. 5 is a line segment connecting the average values of the two measurement results.

As is known from the figure, the sample containing pitch-based graphite has excellent wear resistance.
In addition, the wear amount decreases in the order of crosslinked PPS, semi-crosslinked PPS, and linear PPS regardless of whether pitch-based graphite CF or pitch-based carbon CF is used. Therefore, it is understood that the sample containing the linear PPS has the best wear resistance. Therefore, it can be seen that the sample containing both the linear PPS and the pitch-based graphite CF has excellent wear resistance.

[Brief description of drawings]

FIG. 1 is a sectional view of a scroll compressor according to a first embodiment.

FIG. 2 is a perspective view of a movable scroll member according to the first embodiment.

FIG. 3 is a cross-sectional view of a main part of a movable scroll member according to the first embodiment.

FIG. 4 is a cross-sectional view of a movable scroll member and a fixed scroll member according to the first embodiment.

FIG. 5 is a diagram showing the relationship between the type of PPS and the type of CF and the amount of wear in the third embodiment.

[Explanation of symbols]

 1. . . Scroll compressor, 2. . . Fixed scroll member, 20, 30. . . Short edition, 21, 31. . . Tip seal, 22, 32. . . Spiral blade, 3. . . Movable scroll member, 40. . . Working chamber, 41. . . Suction pressure chamber, 42. . . Discharge pressure chamber,

Claims (6)

[Claims] 1. A linear polyphenylene sulfide resin 20 to 90% (weight%, the same hereinafter), carbon fiber 5 to 40%, and polytetrafluoroethylene 5 to 5.
A tip seal for a scroll compressor, characterized by being mixed with 40% and molded. 2. The tip seal for a scroll compressor according to claim 1, wherein the carbon fiber is a pitch-based graphitic carbon fiber. 3. A polyphenylene sulfide resin 20 to
90%, pitch-based graphitic carbon fiber 5-40
% And polytetrafluoroethylene 5 to 40% are mixed and molded, and a tip seal for a scroll compressor. 4. A fixed scroll member having a spiral blade and an end plate supporting the spiral blade, and a fixed scroll member having a spiral blade and an end plate supporting the spiral blade and arranged to face the fixed scroll member. Is installed and prevents rotation,
The movable scroll member is configured to perform an orbital motion, and is formed between the fixed scroll member and the movable scroll member. The orbital motion of the movable scroll member causes the spiral blade to move toward the central axis from the outer peripheral side. A plurality of working chambers configured to gradually decrease in volume,
A discharge pressure chamber into which high-pressure fluid discharged from the center side of the plurality of working chambers flows, and a suction pressure chamber that introduces low-pressure fluid to the outer peripheral side of the plurality of working chambers, each of which has a tip end of each spiral blade. In a scroll compressor in which tip seals are respectively arranged in the above, the tip seals are made of linear polyphenylene sulfide resin 20 to 90%, carbon fiber 5 to 40%, and polytetrafluoroethylene 5 to 40%. Scroll compressor characterized by. 5. The scroll compressor according to claim 4, wherein the carbon fiber is a pitch-based graphitic carbon fiber. 6. A fixed scroll member having a spiral blade and an end plate for supporting the spiral blade, and a spiral scroll and an end plate for supporting the spiral blade, the fixed scroll member being arranged to face the fixed scroll member. Is installed and prevents rotation,
The movable scroll member is configured to perform an orbital motion, and is formed between the fixed scroll member and the movable scroll member. The orbital motion of the movable scroll member causes the spiral blade to move toward the central axis from the outer peripheral side. A plurality of working chambers configured to gradually decrease in volume,
A discharge pressure chamber into which high-pressure fluid discharged from the center side of the plurality of working chambers flows, and a suction pressure chamber that introduces low-pressure fluid to the outer peripheral side of the plurality of working chambers, each of which has a tip end of each spiral blade. In a scroll compressor in which tip seals are respectively arranged in the above, the tip seals are composed of 20 to 90% of polyphenylene sulfide resin, 5 to 40% of pitch-based graphitic carbon fiber, and 5 to 40% of polytetrafluoroethylene. A scroll compressor characterized by: