JPS5920503A - Fitting structure of ceramic turbine - Google Patents

Abstract

PURPOSE:To easily perform right centering and realize excellent tightening of the captioned structure, in which a turbine rotor and a metal shaft are connected and tightened to each other with a bolt, by providing on the periphery of the bolt a metal sleeve which separates the bolt from the rotor. CONSTITUTION:A turbine rotor 2 and a metal shaft 3 are connected together by means of a coupling part 1, while a bolt 4 is inserted through a fitting hole 2A of the rotor 2 and tightened. In this case, metal sleeves 10 are inserted into the metal shaft 3 through respective insertion holes 3B, 10A. The sleeve 10 is provided with not only a flange part 10B on the rotor 2 side but also a seat face 10C to be contacted by a tapered face 4A of the bolt 4. Thus, right centering of an axis and also excellent tightening can be performed by means of a screw hole 3A and the seat face 10C through only fitting the sleeve 10 to the rotor 2 and the metal shaft 3.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a structure for mounting a ceramic turbine, and in particular to a structure in which a turbine rotor formed of ceramic is coupled to a metal shaft by a curvic coupling.

In recent years, with the shift to ceramics for gas turbine engines,
Molding the turbine rotor with ceramics, and making the ceramic turbine rotor and compressor impeller? A structure in which the ceramic turbine rotor is connected via a metal shaft has been developed, and in such a case, it is possible to use a curvic coupling (registered trademark of Gleason Co., Ltd.) to connect the ceramic turbine rotor to the metal shaft.

When a ceramic turbine rotor and a metal shaft are coupled using such a curvic coupling, a structure as shown in FIG. 1 may be considered, for example. here,
/ is the carbinta cutting part. A curvic coupling is known as a coupling joint that transmits high loads, and this coupling part of the turbine rotor tacho and metal shaft 3 has curved tooth surfaces that form an arc when viewed in cross section perpendicular to the shaft 3. and both sides are carved with convex-shaped and hun-cape-shaped teeth, and by interlocking these toothed rocks, a combined body is constructed. The rotor 2 and shaft 3 connected in this way are connected to the upper shaft 3. It is tightened by screwing into the screw hole 3A of
Ro facing A! There is a mounting hole on the octopus side, and a surface 2B is formed around the two people, and when tightening, the taper surface tA of the Poldog is pressed against the surface λB of the ischia J: Rerotaco and metal shaft 3 Centering is performed.

However, when installing such a ceramic turbine, a metal fastener is generally used, so its expansion coefficient is different from that of a ceramic rotor.
Metals elongate much more than ceramics due to heat. Therefore, in the turbine rotor tacho and metal shaft 3, which are placed in an atmosphere of high-temperature gas ranging from 9oooc to /θ0θ0c, there is a risk that the curvic coupling portion l may loosen due to the extension of the pole dog due to the structure of the installation. There is.

For this reason, it is necessary to set a short pole) + in consideration of the extension allowance in advance, and by fastening it using a loose pole, excessive stress will be generated on the ischial surface of the ceramic rotor λ, 2B. . In addition, the countersunk head of the pole + expands in the radial direction due to the high temperature, and the ischial bone presses against the surface jB, causing stress. Furthermore, the centering accuracy of the screw hole 3A of the metal shaft 3 is incorrect. , causing a tilt in the pole dog, and the tapered surface yh of the countersunk head places an unbalanced load on the ischial surface, 2B, which tends to cause cracks on the ischial surface, 2B, due to the causes of KofL et al.

The object of the present invention is to eliminate the above-mentioned drawbacks, and to prevent the sit bones made of ceramic from bending in a W-contact manner with the surface by fastening bolts. Our goal is to provide the following.

In order to achieve this object, in the present invention, the ceramic rotor and the metal shaft are fastened together by metal fastening bolts via a metal sleeve in which the centering seat bone is provided with a surface.

The present invention will be described in detail below based on the drawings.

Figure 1 shows an embodiment of the invention, where /.

is a metal sleeve, and the end of the metal sleeve 10 has a fitting part / which fits into the fitting hole JB drilled in the metal shaft 3.
θA is provided. 10B is a flange portion provided on the rotor octopus side of the metal sleeve 10, and /θC is a seat bone surface of the sleeve 10 against which the tapered face A of the fastening pole dog is brought into contact when the fastening pole dog is fastened. Thus, the metal sleeve 10 is connected to the rotor λ and the gold 8
When fitted together with the combined body with @3, v, that is, the flange T'KI10B of the sleeve 10 is brought into contact with the side surface of the rotor tacho, and the fitting part IOA is inserted into the fitting hole 3 of the shaft 3.
B and ID (in the combined and U-shaped state, this ischial bone should be centered through the plane loC so that the correct axis position can be centered.

Note that the other configurations are the same as the example shown in FIG.

The structure of installing the ceramic turbine constructed in this way is to connect the ceramic rotor a and the metal shaft 3 by meshing with each other at the curvic coupling part l, and then punch a somewhat larger hole into the IJ rotor tacho mounting hole 2A. Fitting the metal sleeve 10 and fitting the fitting part /θA of the sleeve 10 into the fitting hole 3B of the shaft 3, and attaching the Poldog to the metal sleeve 10.
and screw into the screw hole 3A to fasten. According to the configuration of this example, by simply fitting the metal sleeve 10 to the rotor tacho and the metal shaft 3, the screw hole 3A and the ischial bone can be correctly centered with respect to the plane IOC. ) 9, even if there is a tendency to tilt when fastening, the ischial bones with high rigidity are corrected by the surface IOC side by sliding contact with the bolts. In this way, the fastening bolt q is screwed into the screw hole 3A while being guided by the metal sleeve 10,
In the meantime, the sleeve 10 is fitted into the fitting hole 7B of the metal shaft 3, and in the fastened state, the flange portion 10B of the sleeve 10 is fitted into the fitting hole 7B of the metal shaft 3.
comes into contact with the surface of the rotor tacho, thereby allowing the rotor tacho and the metal shaft 3 to be concentrically connected to the correct axial center position.

As described above, according to the present invention, a metal sleeve is provided between the fastening bolt that connects the rotor and the metal shaft by penetrating the ceramic rotor and screwing it onto the metal shaft, and the rotor and the metal shaft. By interposing this metal sleeve between both sides, the seat bone for the bolt head provided on the metal sleeve is able to center the axis on the plane, so the metal bolt can be tightened. It is possible to prevent the occurrence of cracks caused by the unbalanced load caused by the fastening force and tilting of the bolts being applied directly to the surface of the ceramic rotor's seat bones, as in the case of conventional methods, and it is easy to achieve correct centering. It is possible to maintain the connection between the meter and the metal shaft using the curvic coupling in the correct fastening position without strain.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an example of a possible structure for installing a ceramic turbine using a curvic coupling, and Fig. 2 is a sectional view showing an example of a structure for installing a ceramic turbine according to the present invention. . l...Curvic coupling part, Co...Turbine rotor, UA...Mounting hole 1, IB...Ischial bone is surface, 3...Metal shaft, 3A...Threaded hole, l ...Fastening bolt, +A...Taber surface, 10...Metal sleeve, IOA...Fitting part, 1033...Flange part, IOC...Ichial bone is a surface. Special fraud applicant Nissan Motor Co., Ltd.

Claims (1)

[Claims] /) Joints provided on each of a ceramic turbine rotor and a metal shaft are joined, and the ceramic turbine rotor is attached by screwing a fastening bolt passed through a hole to the metal shaft. Additionally, the ceramic turbine rotor and the metal shaft can be mounted by interposing a metal sleeve around the fastening bolts to isolate the ceramic turbine rotor from the ceramic turbine rotor. The metal sleeve is extended toward the metal shaft, the extending portion of the metal sleeve is fitted onto the metal shaft, and the fastening bolt is screwed onto the metal shaft. A ceramic turbine mounting structure is characterized in that the metal sleeve is in pressure contact with the ceramic turbine rotor. 2. The mounting of the ceramic turbine according to claim 1 is structured such that the head bearing surface of the fastening bolt is in pressure contact with the ceramic turbine rotor through a bearing provided on the metal sleeve. The installation of the ceramic turbine is characterized by its structure.