JPH0291401A - Moving blade of oil free type air engine - Google Patents

Abstract

PURPOSE:To improving slidability and heat-resistance of an air engine while improving ability thereof by forming moving blades from aromatic polyester resin having specified value of thermal expansion coefficient. CONSTITUTION:Moving blades 1 of a rotor 5 are made from aromatic polyester resin having thermal. expansion coefficients of 2X10<-5> or lower. Slidability and heat-resistance are improved accordingly by adopting aromatic polyester resin. Since the thermal expansion coefficient is set to not more than 2X10<-5>, gaps between grooves 6 of a disc 7 and the moving blades 1 are minimized, so that ability of an air engine is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a movable blade for a non-lubricated air engine used, for example, in cement powder feeding equipment.

(Prior Art) Conventionally, an air engine using movable blades l shown in FIG. 1 is known.

This air engine is rotatable about a rotary shaft 4 provided eccentrically with respect to the center of the rotor chamber 3 in a rotor chamber 3 having a circular cross section and communicating with intake ports 1a, lb and exhaust port 2. It is formed by attaching the rotor 5. The rotor 5 also includes a disk 7 in which a large number of radial grooves 6, for example, six as shown in the figure, are drilled at regular angular intervals in the circumferential surface, and a disk 7 that is always directed outward in the WIIB. While encouraging
It consists of a movable blade that is slidably fitted. In the vicinity of the intake ports 1a and lb that make sliding contact with the wall surface of the rotor chamber 3, movable blades! While the whole is fitted into the groove 6, the movable blade l is made to protrude outward from the disk 7 as it approaches the part of the exhaust port 2 that is farthest from the wall surface of the rotor chamber 3, thereby forming a sealed space between the movable IT members. And it is gradually expanding.

In addition, as for the material of the movable blade 1, metal materials such as aluminum alloy are used when the air engine is lubricated using oil, etc., because the material properties such as impact and bending characteristics are sufficiently satisfied. In the non-lubricated rotor, there is a problem that if the metal material mentioned above is used, it will damage the wall surface of the rotor chamber. For this reason, in the non-lubricated type, the movable blade 1
The main material used is graphite, which does not damage the other side with which it slides.

Further, the intake ports 1 a and 1 b reach the intake passage 8 in a manner that can be switched as appropriate, and the compressed air guided to the intake passage 8 is supplied into the rotor chamber 3 .

Then, the rotor 5 is rotated in the direction of the arrow by the pressure of the compressed air supplied from the intake port 1a, or rotated in the opposite direction by the compressed air supplied from the intake port 1b, and the expanded air is exhausted from the exhaust port 2. There is.

(Problems to be Solved by the Invention) Although the graphite material used as the material for the movable blade 1 has excellent sliding properties and low heat generation due to friction, and has the characteristics required for the movable blade 1, it has poor impact characteristics. There are problems such as cracking and chipping are likely to occur, and the service life is short and cannot be predicted.

The present invention has been made to address the above-mentioned conventional problems, and aims to provide a movable blade for a non-lubricated air engine that has excellent sliding properties, heat resistance, and impact characteristics.

(Means for Solving the Problems) In order to solve the above problems, the first invention is made of an aromatic polyester resin having a coefficient of thermal expansion of 2XIO-''5 or less.

Further, a second invention provides the above-mentioned aromatic polyester resin;
It was formed from a reinforcing material that was filled into this and had a weight ratio of 50% or less of the total weight.

(Example) Next, the present invention will be explained.

The present invention is the same as shown in FIG. 1 in the drawings, and hereinafter, FIG. 1 will be used to illustrate the present invention, and the description of the apparatus will be omitted because it is as described above. That is, FIG. 1 shows an air engine to which the movable blade l according to the present invention is applied.

The movable blade 1 according to the first invention has a thermal expansion coefficient of 2X.
10-5 or less, preferably 1.5 x 10-5 or less, such as Vectra (trade name,
Celanese Co., Ltd. (USA)) and U Polymer (trade name, manufactured by Unitika Co., Ltd.).

Specifically, it is formed as follows.

Using Vectra, an aromatic polyester resin,
Create movable wings by injection molding. To create this movable wing, an injection mold having the same dimensions and shape as the movable wing is prepared in advance. The dimensions of this mold are determined in consideration of thermal shrinkage based on the unique properties of each material, molding shrinkage due to crystallization, elastic recovery, etc. However, since the molding shrinkage rate differs depending on the flow direction of the resin and the direction perpendicular to it, each direction should also be taken into account when studying.

Next, as for the molding conditions, the cylinder and nozzle temperatures are adjusted so that the resin temperature is about 290-300°C, and the mold temperature is set in the temperature range of 80-100°C. Further, the injection pressure is in the range of 150 to 450 kgr/cm''.

In this way, aromatic polyester resin was used because it has excellent sliding properties and heat resistance, with a heat resistance temperature of 150°C or higher, and it also has a thermal expansion coefficient of 2 x 10-5 or less. As a result of experiments, when is larger than this value, the clearance required for the sliding part of the movable blade l increases and the performance of the air engine decreases, whereas below this value, the above clearance reduces the performance of the air engine. This is because the performance degradation can be ignored.

Next, Table 1 shows the experiments and simulations conducted to compare the movable blade according to the first invention (indicated by A in the table) and the movable blade made of conventional graphite material (indicated by B in the table). Show the results.

(The following is a blank space) Table 1 As shown in the above results, the first invention exhibits superior characteristics in each test item compared to the insulator made of graphite material.

In addition, when an air engine uses movable blades made of graphite material, most of the movable blades break and become unusable within 2 months to 3 years after use. The one we used was able to start up and operate under load repeatedly for three years without any cracking or chipping.

Next, the movable blade 1 according to the second invention is formed from the above-mentioned aromatic polyester resin and a reinforcing material, for example, glass fiber, which is filled into the aromatic polyester resin in a weight ratio of 50% or less of the whole.

Specifically, it is formed as follows.

It is molded by injection molding using PEEK resin filled with 30% glass fiber.

Molding conditions Resin temperature: 370 to 380°C Mold temperature: 160 to 190°C Injection pressure: 700 to 1400 kgf/c+a''.

In this way, the filling amount of glass fiber is 50% by weight.
The reason for setting the value below is that if this value is exceeded, the amount of wear on the wall surface of the rotor chamber 3 that comes into sliding contact with the movable blade l will be large;
This is because the amount of wear can be ignored if it is less than this value.

Moreover, due to each formation in this way, the coefficient of thermal expansion is 1.
16xlo-', the impact strength was 50 kg-cm, the bending strength was 1300 kg-cm, the heat resistance temperature was 200°C, and it could be used for 3 years in actual machine tests.

In addition to the above, examples of the reinforcing material include carbon fiber and SiC fiber, and it does not matter whether it is a whisker or a powder.

Furthermore, the present invention is not limited to injection molding, but may also be compression molding, depending on the grade of the resin.

In addition to the materials in the first and second inventions, by filling graphite in an amount of 30% or less of the total weight ratio, the decrease in strength of the movable blade can be suppressed to a negligible level and the sliding characteristics can be improved. However, if it exceeds 30%, the strength against one impact bending becomes a problem.

(Effects of the Invention) As is clear from the above description, according to the first invention, it is formed from an aromatic polyester resin having a coefficient of thermal expansion of 2xlO-5 or less.

Therefore, even without lubrication, it has excellent sliding properties and heat resistance, and it is possible to reduce the gap between the movable blade sliding parts and improve the performance of the air engine.

Further, according to the second aspect of the invention, it is formed from the above-mentioned aromatic polyester resin and a reinforcing material filled therein with a weight ratio of 50% or less of the total weight.

Therefore, in addition to the effects of the first invention, it is possible to reduce the coefficient of thermal expansion, improve impact and bending strength, increase the allowable temperature limit, and improve durability.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an air engine using movable wings, and FIG. 2 is a schematic front view showing the means on which the simulation was based. l...Movable wings. Patent applicant: Kobe Steel, Ltd. Representative Patent attorney: Aoyama Aoyama and one other person

Claims (2)

[Claims] (1) A movable blade for a non-lubricated air engine, characterized in that it is formed of an aromatic polyester resin having a coefficient of thermal expansion of 2×10^-^5 or less. (2) A movable blade for a non-lubricated air engine, characterized in that it is formed from the above-mentioned aromatic polyester resin and a reinforcing material filled therein in a weight ratio of 50% or less of the total weight.