JPS60228705A - Hollow blade - Google Patents

Abstract

PURPOSE:To suppress vibration, by welding one end of a reinforcing plate to one of opposed plate-like outer members of a hollow blade, and engaging the other end of the reinforcing plate with an engagement member provided on the inside surface of the other outer member. CONSTITUTION:One end of a reinforcing plate 6 is welded at 7 to one plate- like outer member 4 of a hollow blade 1d, and the other end of the reinforcing plate 6 is movably engaged with an engagement member 10 provided by welding at 7 on the inner surface of the other plate-like outer member 3 opposed to the outer member 4. With this arrangement, vibration energy may be absorbed by collision and friction to thereby suppress vibration.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to hollow blades used in various rotating machines such as blowers, compressors, superchargers, steam durbins, and gas turbines.

Rotor blades used in rotating machines have various structures. FIG. 1 is a plan view of a typical rotor blade, in which 1 shows the blade body and 2 shows the blade root. This blade root portion 2 is coupled to a rotating disk, rotating shaft, etc. (not shown).

Chord direction of the wing body 1 (i.e. direction of line A-A in Fig. 1)
Most of the cross sections are solid, as shown in FIG. 2, for example. Such a solid wing has X,
The drawback is that various vibrations in the Y and Z axis directions are large.

On the other hand, the blade 1 is not solid but has a hollow shape, in which plate-shaped outer surface materials 3.4 are stretched together and the joint parts 5 are welded, as shown in FIG.
a. A wing 1b in which a reinforcing member 6 is welded in the chord direction as shown in FIG. 5 inside the hollow wing 1a, and a wing IC shown in FIG. Are known.

However, since the mating part 5 of the blade 1a is welded, structural damping against vibration cannot be expected, and although the blade 1b has a higher rigidity than the blade 1a, it has a more complex structure and has less structural damping. It's not something you can expect much from. Furthermore, since the reinforcing member 6 of the wing IC is fixed with a rivet 9, it is expected that the wing 1b will have a friction structure damping generated from the rivet joint, but since the rivet joint is usually a tight joining means, The friction structure damping that occurs is not very large.

In view of the above circumstances, the present invention has been made with the object of providing a hollow blade that is highly effective in suppressing vibrations.

Examples of the hollow blade according to the present invention are shown in FIGS. 7 to 14 below.
This will be explained in detail with reference to the drawings. In these figures, the same parts as in FIGS. 1 to 6 are designated by the same reference numerals.

FIG. 7 is a cross-sectional view showing the first embodiment of the present invention, in which the hollow blade 1d is made by stretching plate-shaped outer members 3.4 and welding the joint 5 to form a rigid connection. are similar to those in FIGS. 5 and 6. However, the present invention is characterized in that the reinforcing member 6 provided in the chord direction is movably connected.

That is, one end of the reinforcing member 6 is fixed to the inner surface of one of the outer members 4 by welding. The other end edge of the reinforcing member 6 is mechanically connected with a slight gap to a fitting portion having a recess, for example, of a fitting member 10 welded to the inner surface of the other opposing outer surface plate 3. Fitted and held.

FIG. 8 shows another embodiment of the present invention. 8th
The hollow blade 1e of the embodiment shown in the figure has reinforcing members 6 installed in two places in the chord direction, and the other parts have reinforcing members 6 installed in two places.
This is similar to the embodiment shown in the figure.

In this way, the reinforcing members 6 may be provided at two or more locations. In the embodiment shown in FIG. 8, one reinforcing member 6 is welded to the outer plate 3, and the other reinforcing member 6 is welded to the outer plate 4. Therefore, the fitting members 10 are also fixed to the outer plates on opposite sides. Note that these reinforcing members 6 and fitting members 10
can be fixed to either outer plate.

FIG. 9 shows a third embodiment of the present invention. The hollow blade 1f of this embodiment differs from the embodiments shown in FIGS. 7 and 8 in the direction in which the reinforcing plate 6 is attached. That is,
In the embodiments shown in FIGS. 7 and 8, the reinforcing plate 6 is provided in the chord direction, but in this embodiment, the reinforcing plate 6 is arranged in the wing length direction and is welded to the inside of the outer surface plate. This embodiment is similar to the embodiments shown in FIGS. 7 and 8 in that the other end of the reinforcing plate is fitted into the fitting portion of the fitting member with a slight gap. The reinforcing plate 6 may be provided at one place or at two or more places.
As shown in the figure, there is one reinforcing plate 6 in one area of the hollow blade 1f when viewed in the chord direction, but there are two reinforcing plates 6 in other areas.

10 to 14 show various shapes of the fitting portion between the reinforcing plate 6 and the fitting member 10.

That is, in FIG. 10, a bulge 6a is formed at the tip of the reinforcing plate 6, and the fitting member 10 side is shaped to fit into the bulge 6a. FIG. 11 shows the bulging portion 6a in a triangular shape, and FIG. 12 shows the bulging portion 6a in a T-shape. Furthermore, FIGS. 13 and 14 show an embodiment in which the fitting member 10 is plate-shaped and a fitting portion is formed on the front end side of the reinforcing plate 6.

Although various embodiments have been shown above, the hollow blade of the present invention is one in which a reinforcing plate provided inside the outer surface material is multi-connected by fitting one edge of the reinforcing plate to the peripheral outer surface plate without welding it to the peripheral outer surface plate. It is. Therefore, energy loss due to collision and energy loss due to friction occur due to the fitting portion, and therefore the amplitude of vibration is suppressed. That is, a hollow blade capable of suppressing vibration is provided.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a general wing, Fig. 2 is a cross-sectional view of a conventional solid wing in the chord direction, Fig. 3 is an explanatory diagram of the solid wing shown in Fig. 2, and Figs. Fig. 6 is a chord-direction sectional view of different types of conventional hollow blades, Fig. 7 is a chord-direction sectional view showing one embodiment of the hollow blade according to the present invention, and Fig. 8 is a chord-direction sectional view showing another embodiment of the present invention. FIG. 9 is a chordwise sectional view of a hollow blade showing an example; FIG. 9 is a plan view of a blade shown for explaining still another embodiment of the present invention;
0 to 14 are sectional views showing different embodiments of the fitting portion between the reinforcing plate and the fitting member that can be employed in the present invention. 1, ld, le, If @ @ wing body, 2... wing root,
3゜4... External material, 6... Reinforcement plate, 10... Fitting member. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] In a hollow wing made of a plate-shaped outer material and formed into a hollow shape, one end edge of the reinforcing plate is welded to one of the opposing inner surfaces of the outer material, and the other end edge of the reinforcing plate is welded to the opposite inner surface of the outer material. A hollow wing, characterized in that it fits into a fitting member provided on the opposing inner surface of the hollow wing.