JP2676960B2 - Quality assurance test method for ceramic turbocharger rotor with resin compressor impeller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the invention]

(Field of Industrial Application) The present invention relates to a ceramic turbocharger rotor with a resin compressor impeller used to perform a quality assurance test of a ceramic turbocharger rotor with a resin compressor impeller used in a turbocharger of an automobile. It relates to a quality assurance test method. (Prior Art) It was in 1979 that turbochargers were fully installed in passenger car engines in Japan, and since then, improvements in engine dynamic performance have been favored, and the number has continued to steadily increase. However, in order to further improve performance,
It was desired to improve the acceleration performance in the low speed range and reduce the so-called turbo lag peculiar to turbo cars. Although various methods can be considered to reduce this turbo lag, it is effective to reduce the weight of the turbocharger rotor to reduce the moment of inertia, and it is possible to achieve a significant weight reduction compared to conventional nickel-based metal materials. In October 1985, the world's first passenger car equipped with a ceramic turbocharger rotor (“Service Weekly Report No. 542 NISSAN Fairlady Z” issued by Nissan Motor Co., Ltd. in October 1985) was considered. It came to be sold. Therefore, as a quality assurance test method to be performed after manufacturing such a ceramic turbocharger rotor, see "Ceramics" Vol. 23, No. 7 (1988), pages 638 to 641 issued by the Japan Ceramic Society. As described in the document entitled "Reliability of ceramics turbocharger rotors", all ceramic turbocharger rotors are overloaded in advance and only those that have passed this guarantee test are used. Was there. (Problems to be Solved by the Invention) However, in the quality assurance test method after manufacturing such a conventional ceramic turbocharger rotor, the compressor impeller is applied to a material made of an aluminum alloy. When a resin (polymer base composite material) compressor impeller is used instead of the alloy compressor impeller, the overload is applied as described above during the quality assurance test, so the rotation speed is much higher than the rated speed. Therefore, the outlet temperature of the compressor impeller becomes much higher than when it is used below the rated speed, and in the case of the polymer-based composite material used for this compressor impeller, the matrix phase is a polymer material. For this reason, this matrix is used in a high-temperature atmosphere regardless of the thermoplastic resin and thermosetting resin. There is a problem in that the strength is reduced under ambient conditions. On the other hand, the stresses acting on the compressor impeller are mainly thermal stress and centrifugal stress. Especially, the latter centrifugal stress increases in proportion to the square of the number of rotations. More than double stress is applied. Therefore, in the quality assurance test method of applying such an overload, there is a problem that the resin compressor impeller, rather than the ceramic turbocharger rotor, is likely to be destroyed in a high temperature atmosphere. (Object of the Invention) The present invention has been made in view of such a conventional problem, and when performing a quality assurance test of a ceramic turbocharger rotor equipped with a resin compressor impeller, particularly, a rated speed during use. Even if the ceramic turbocharger rotor may be damaged when a quality assurance test is performed due to overloading by rotating at a rotational speed higher than that, the resin compressor impeller should not be damaged prior to this. In addition, it is an object of the present invention to be able to more reliably perform a quality assurance test of a ceramic turbocharger rotor.

Configuration of the Invention

(Means for Solving the Problems) A quality assurance test method for a ceramic turbocharger rotor with a resin compressor impeller according to the present invention is performed when performing a quality assurance test on a ceramic turbocharger rotor having a resin compressor impeller, A compressor outlet temperature reducing means is provided to reduce the temperature of the compressor outlet at high rotation of the resin compressor impeller and prevent destruction of the resin compressor impeller during quality assurance test of the ceramic turbocharger rotor. In one embodiment, the compressor outlet temperature reducing means is configured by a mechanism such as a vacuum pump that decompresses an intake system including a compressor, and in another embodiment, the compressor outlet temperature reducing means is configured. The outlet temperature reducing means is configured by a mechanism such as a compressor cap that blocks the flow of air to the compressor inlet portion. In yet another embodiment, the compressor outlet temperature reducing means is a compressor impeller. It is characterized in that it is configured by a mechanism that uses itself as a depressurizing means of the intake system, and has the above-mentioned conventional problems regarding the configuration of the quality assurance test method for the ceramic turbocharger rotor with a resin compressor impeller as described above. It is a means to solve it. (Operation of the Invention) Since the quality assurance test method for the ceramic turbocharger rotor with a resin compressor impeller according to the present invention has the above-mentioned configuration, a ceramic turbocharger having a resin compressor impeller is provided. Especially when conducting a quality assurance test of the rotor by applying an overload, the temperature at the compressor outlet is reduced by the compressor outlet temperature reducing means.Therefore, even if a resin compressor impeller is used, the above-mentioned resin Deterioration of the strength of the manufactured compressor blade is suppressed, and even if the ceramic turbocharger rotor may be broken during the quality assurance test, the resin compressor impeller will not be broken earlier than this. To become Therefore, the quality assurance test of the ceramic turbocharger rotor in the ceramic turbocharger rotor with the resin compressor impeller can be performed more reliably. (Embodiment) Embodiment 1 FIG. 1 shows a first embodiment of the present invention.
In the turbocharger 1 shown in FIG. 1, a resin compressor impeller 3 is connected to one end side of a shaft 2 and a ceramic turbocharger rotor 4 is connected to the other end side thereof, respectively, a compressor housing 5 and a turbine. The housing 6 is adapted to rotate at a high speed. Further, the compressor housing 5 is provided with a compressor inlet 7 and a compressor outlet 8, and the former compressor inlet 7 is provided with a rotation speed detecting coil 9 and a vacuum pump via a pipe 11.
The vacuum pump 12 acts as a mechanism for reducing the pressure of the intake system such as the compressor inlet 7 and the compressor outlet 8, and a pipe 13 is connected to the latter compressor outlet 8. On the other hand, the turbine housing 6 is provided with a turbine inlet 15 and a turbine outlet 16, and the former turbine inlet 15 is provided with a gas supply control valve 18 via a pipe 17.
And a gas supply source 19 is connected to this gas supply control valve 18, and a pipe 20 is connected to the latter turbine outlet 16 and the high temperature exhausted from this pipe 20 The gas is recycled by returning it to the gas supply source 19. Further, there is provided a spin tester controller 21 for controlling the opening of the gas supply control valve 18 based on the information on the number of revolutions sent from the revolution number detecting coil 9. The turbocharger rotor 4 made of ceramics is manufactured by using the quality assurance test apparatus for the turbocharger 1 having the above-mentioned configuration.
During the quality assurance test by applying overload to
When the temperature at the compressor inlet 7 is T ₇ , the temperature at the compressor outlet 8 is T ₈ , the pressure at the compressor inlet 7 is P ₇ , the pressure at the compressor outlet 8 is P ₈ , and the compressor efficiency is ηc, the following relationship holds. To do. _{T 8 = T 7 + {T} 7 × [(P 8 / P 7) 0.86 -1]} / ηc ...... (1) where, the intake system including the resin compressor impeller 3 of the turbocharger 1 (i.e., compressor inlet 7
And the compressor outlet 8 and the entire components of the intake system including the pipes 11 and 13 connected to them) are decompressed by the operation of the vacuum pump 12, the pressure P at the compressor inlet 7 is particularly high in a vacuum state. ₇ = pressure P _{8 at the} compressor outlet 8 becomes, and [(P ₈
Since / P ₇ ) ^0.86 −1] = 0, the temperature T ₈ of the compressor outlet ₈ = the temperature T ₇ of the compressor inlet 7 theoretically, and the temperature of the compressor outlet 8 theoretically does not rise. Therefore, the temperature rise of the compressor outlet 8 can be prevented or suppressed by this, and even when the quality assurance test due to the overload on the ceramic turbocharger rotor 4 is carried out, the resin caused by the temperature rise of the compressor outlet 8 is caused. It is possible to prevent the compulsory lowering of the compressor impeller 3 made of resin, and it is possible to prevent the resin compressor impeller 3 from being destroyed before the turbocharger rotor 4 made of ceramics during the quality assurance test. Therefore, the quality assurance test of the ceramic turbocharger rotor 4 can be performed more reliably and accurately. Embodiment 2 FIG. 2 shows a second embodiment of the present invention,
In the turbocharger 1 shown in FIG. 2, a resin compressor impeller 3 is connected to one end side of a shaft 2 and a ceramic turbocharger rotor 4 is connected to the other end side thereof, respectively, a compressor housing 5 and a turbine. The housing 6 is adapted to rotate at a high speed. The compressor housing 5 is provided with a compressor inlet 7 and a compressor outlet 8, and the former compressor inlet 7 is provided with a rotation speed detecting coil 9 and is located closer to the compressor than the pipe 11 is. A compressor cap 22 is provided to prevent air from flowing into the compressor inlet 7, and a pipe 13 is connected to the latter compressor outlet 8. On the other hand, the turbine housing 6 is provided with a turbine inlet 15 and a turbine outlet 16, and the former turbine inlet 15 is provided with a gas supply control valve 18 via a pipe 17.
And a gas supply source 19 is connected to this gas supply control valve 18, and a pipe 20 is connected to the latter turbine outlet 16 and the high temperature exhausted from this pipe 20 The gas is recycled by returning it to the gas supply source 19. Further, there is provided a spin tester controller 21 for controlling the opening of the gas supply control valve 18 based on the information on the rotation speed sent from the rotation speed detection coil 9. The turbocharger rotor 4 made of ceramics is manufactured by using the quality assurance test apparatus for the turbocharger 1 having the above-mentioned configuration.
When the quality assurance test is performed by applying an overload to the above, since the resin compressor impeller 3 itself is used as the vacuum pump in the first embodiment, it is not necessary to use a vacuum pump. ing. That is, during the quality assurance test, the ceramic turbocharger rotor 4 is rotated by the high temperature gas supplied from the gas supply source 19, and the compressor impeller 3 is rotated together with this rotation, whereby the compressor impeller 3 is rotated. Performs compression work, but during this quality assurance test, the compression work is wasted because the compressor is not connected to the internal combustion engine. Therefore, in the second embodiment, a compressor cap 22 is provided at the compressor inlet 7, and the compression work of the compressor impeller 3 is utilized to discharge the air between the compressor impeller 3 and the compressor cap 22. The pressure is reduced. Then, when the operation of the turbocharger 1 is stopped, the pressure between the compressor cap 22 and the compressor impeller 3 becomes equal to the atmospheric pressure, but the supply of high-temperature gas causes the turbocharger rotor 4 to rotate. When the compressor impeller 3 rotates together with this, the air between the compressor cap 22 and the compressor impeller 3 is immediately discharged, so that the compressor inlet 7
The side is decompressed. At this time, since air remains between the compressor cap 22 and the compressor impeller 3, the temperature may rise slightly immediately after the start of the test,
Since the compressor inlet 7 side is depressurized as the rotation speed increases, the influence of residual air between the compressor cap 22 and the compressor impeller 3 decreases. In the second embodiment, the compressor impeller 3
Since it uses itself as a vacuum pump, it is remarkably inexpensive as compared with the case of the first embodiment because it does not require a vacuum pump, and since it does not use a vacuum pump, electricity and oil associated therewith are saved. It has excellent advantages such as that it is not necessary, no modification of conventional equipment is required, and decompression time is hardly required. Evaluation Experimental Example In this evaluation experimental example, a comparative evaluation test with a conventional example was performed for the case where the vacuum pump 12 was used in the first example and the case where the compressor cap 22 was used in the second example. The compressor cap 22 used in the second embodiment
Is made of S40C (carbon steel for machine structure), and the inner diameter of the compressor cap 22 is a turbocharger using a ceramic turbocharger rotor 4 (ceramic turbocharger manufactured by Nissan Motor Co .; commonly known as CNR). -1 type) 60mm to fit 1 and high-vacuum grease on the inner wall of compressor inlet 7 (Shin-Etsu Chemical Co., Ltd. high-vacuum grease; HIVAC-G)
Was applied. Further, the test condition by the spin tester controller 21 is that the temperature of the high temperature gas from the high temperature gas supply source 19 is about 600 ° C.
The temperature of the turbine inlet 15 was 341 to 348 ° C, the temperature of the compressor inlet 7 (= atmosphere temperature at the start of the test) was 47 ° C.
The result is shown in FIG. As shown in FIG. 3, in the quality assurance test, when the number of rotations of the shaft 2 is 170,000 times, the compressor outlet temperature is about 165 ° C. in the case of the conventional example, and the compressor cap 22 of the second embodiment is used. The temperature is about 120 ° C. when the vacuum pump 12 of the first embodiment is used, and about 90 ° C. when the vacuum pump 12 of the first embodiment is used, and about 45 ° C. when the compressor cap 22 of the second embodiment is used. A temperature reduction effect of ℃ is recognized. Further, in the first embodiment, about 30 more than in the second embodiment.
Although a temperature reduction effect of about ℃ was recognized, the temperature at the compressor outlet 8 was about 150 ℃ when actually installed in a car.
Since the temperature reduction effect of the first embodiment is excessive, the temperature reduction effect of the first embodiment is excessive. In addition, as described above, the vacuum pump of the first embodiment is not separately used in the second embodiment. Since it has a remarkably excellent effect by the above, it can be said that even the temperature reducing effect in the second embodiment is more than sufficient in the practical quality assurance test. In addition, since the pressure between the compressor cap 22 and the compressor inlet 7 is reduced when the rotational speed is reduced after the initial target rotational speed is reached in order to perform the quality assurance test due to the overload, the compressor outlet 8 side From the above, it was found that the air compressed toward the compressor inlet 7 side may flow back and the temperature may rise, but the stress is low because the rotational speed is decreasing, and the stress on the compressor impeller 3 is reduced. It was found that the above results are practically acceptable since there is little possibility of destruction. Further, according to the present invention, it was also found that there is an advantage that the difficulty of the rotational speed control, which has been a problem in the conventional quality assurance test, can be eliminated. That is, according to the conventional method, even if the gas supply is stopped due to the rotation speeds of the compressor impeller 3 and the turbocharger rotor 4 reaching the target set values, as shown in FIG. Therefore, in this test, the person in charge sets the number of revolutions set based on the experience so far by subtracting from the original target number of revolutions by the excessive number of revolutions due to experience. In the embodiment, since the pressure on the compressor inlet 7 side is reduced, the compressed air flows back from the compressor outlet 8 to the compressor inlet 7 when the gas supply from the gas supply source 19 is stopped, so that the compressor impeller 3 is prevented from over-rotating. Rotation speed detection coil 9 attached to the inlet 7 side
By detecting the number of revolutions with and controlling the supply of gas when this number of revolutions reaches a set value, as shown in FIG. 4, the set number of revolutions and the target number of revolutions become the same value. It can be easily set. In the above embodiment, the compressor cap 22
Although S40C was used as the material of, the material is not particularly limited to this. Further, when the turbocharger 1 is shipped after the quality assurance test of the ceramic turbocharger rotor 4 is performed using the compressor cap 22 as described above, the protective cover of the compressor cap 22 is provided to protect the inside of the turbocharger. It is also desirable to keep it attached as necessary, and in this case it is cheap and reasonably soft resin compressor cap
It is also desirable to use 22 if necessary.

【The invention's effect】

According to the quality assurance test method for a ceramic turbocharger rotor with a resin compressor impeller according to the present invention, when performing a quality assurance test for a ceramic turbocharger rotor equipped with a resin compressor impeller, the quality of the resin compressor impeller is increased. Since the compressor outlet temperature reducing means for preventing the destruction of the resin compressor impeller during the quality assurance test of the ceramic turbocharger rotor by reducing the temperature of the compressor outlet during rotation is provided,
When conducting a quality assurance test on a ceramic turbocharger rotor equipped with a resin compressor impeller,
In particular, even when performing quality assurance tests due to overload that rotates at a rotational speed that is even higher than the rated rotational speed during use, it is possible to prevent an excessive temperature rise at the compressor outlet. However, even if the ceramic turbocharger rotor is destroyed, the resin compressor impeller will not be destroyed before the ceramic turbocharger rotor is destroyed. Therefore, it is possible to set the target rotation speed due to overload remarkably easily, which is a very excellent effect.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a schematic structure of a quality assurance test device used in a first embodiment of the present invention, and FIG. 2 is an explanatory view showing a schematic structure of a quality assurance test device used in a second embodiment of the present invention. FIG. 3 and FIG. 3 are graphs illustrating the results of evaluating the effect of reducing the temperature at the compressor outlet according to the present invention, and FIG. 4 is a graph illustrating the relationship between the spin tester set rotational speed and the compressor impeller actual measured rotational speed. 1 ... Turbocharger, 3 ... Resin compressor impeller (means for reducing compressor outlet temperature; mechanism for decompressing intake system including compressor), 4 ... Ceramic turbocharger rotor, 7 ... Compressor inlet,
8 ... Compressor outlet, 12 ... Vacuum pump (compressor outlet temperature reduction means; mechanism for decompressing intake system including compressor), 15 ... turbine inlet, 16 ... turbine outlet, 22 ... compressor cap (compressor outlet temperature) Reduction means; a mechanism that blocks the flow of air to the compressor inlet).

Claims (4)

(57) [Claims] 1. When performing a quality assurance test on a ceramic turbocharger rotor equipped with a resin compressor impeller, the temperature at the compressor outlet is reduced when the resin compressor impeller is rotating at high speed, and the temperature of the ceramic turbocharger rotor is reduced. A quality assurance test method for a ceramic turbocharger rotor with a resin compressor impeller, characterized in that compressor outlet temperature reduction means for preventing the destruction of the resin compressor impeller during a quality assurance test is provided. 2. The quality assurance test method for a ceramic turbocharger rotor with a resin compressor impeller according to claim 1, wherein the compressor outlet temperature reducing means comprises a mechanism for reducing the pressure of an intake system including the compressor. 3. A quality assurance test method for a ceramic turbocharger rotor with a resin compressor impeller according to claim 1, wherein the compressor outlet temperature reducing means comprises a mechanism for blocking the flow of air to the compressor inlet portion. 4. The quality assurance test method for a ceramic turbocharger rotor with a resin compressor impeller according to claim 1, wherein the compressor outlet temperature reducing means comprises a mechanism that uses the compressor impeller itself as a pressure reducing means for the intake system.