JPH0133763Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a turbomachine, and particularly to a structure around its movable blade.

An example of a conventional structure of a variable stator vane is shown in FIG. FIG. 1 illustrates one of the variable static walls 10 disposed radially between a cylindrical shroud 20 and a similarly cylindrical hub 30, together with its supporting structure. The variable stator vane 10 has its outer end rotatably supported by a sleeve 21 that fits into a hole provided in the shroud 20 and a bearing 22. Further, its inner end is rotatably supported by a bearing 32 that fits into a hole provided in the hub 30. The shaft at the outer end of the variable stator vane 10 extends through the shroud 20 and is connected to the drive lever 40 outside the shroud 20 . By moving this drive lever 40, the variable stator vane 10 rotates around the rotation axis 50, thereby making it possible to change the flow rate of the turbine.

FIG. 2 shows the trajectory of the shroud-side end surface 11 and the hub-side end surface 12 when the variable static concentration 10 rotates in relation to the shroud inner wall 23 and the hub outer wall 33. As is clear from this figure, since the trajectories 71 and 72 due to the rotation of the shroud side end surface 11 and the hub side end surface 12 are on a plane perpendicular to the rotation axis 50, the shroud side end surface 11 changes depending on the angle of rotation. It bites into the shroud inner wall 23 (indicated by amount A), and the gap between the hub side end surface 12 and the hub outer wall 33 changes widely (indicated by amount B). An increase in gap loss occurs due to contact between the end face 12 and the hub outer wall 33 or an enlargement of the gap.

The purpose of the present invention is to solve this problem.According to the present invention, when the variable blade rotates, the tip gap is kept constant, and contact and clearance between the variable blade and the inner surface of the shroud or the outer surface of the hub are increased. Provides an inexpensive structure that prevents increased losses due to

That is, the present invention provides a turbomachine including a flow path having a guide wall on at least one of the inner circumferential side and the outer circumferential side of movable blades disposed radially, the guide wall having a surface facing the end surface of the movable blade. The turbomachine is characterized in that the movable blade has a counterbore that is a plane perpendicular to the rotation axis of the movable blade.

Hereinafter, the present invention will be described in detail with reference to preferred embodiments of the present invention illustrated in FIGS. 3 to 5 of the accompanying drawings.

Although this embodiment is an example in which the present invention is applied to a variable stator vane of a turbomachine, the present invention is not limited to this and can be applied to a variable vane or even a variable guide vane provided in a flow path. Needless to say.

In the illustrated embodiment, the rotation axis 5 of the variable stator vane 100 is
00 is located midway between the leading edge 150 and the trailing edge 160. The movable stator blade 100 is connected to the drive lever 400
The shaft rotates via a shroud-side shaft 170 that passes through the shroud 200.

The shroud side end surface 110 and the hub side end surface 120 of the variable stator vane 100, and the shroud side bottom surface 81 of the counterbore 800 provided in the shroud inner wall 230.
0, the hub side bottom surface 910 of the counterbore 900 provided in the outer wall 330 of the hub 300 is aligned with the rotation axis 5
It is composed of a plane perpendicular to 00. Counterbore 8
00 and the outer periphery 820, 920 of the counterbore 900,
The variable stator vane 100 is slightly farther from the rotation axis than the locus drawn by the leading edge 150 and the trailing edge 160 when the variable stator vane 100 is rotated about the rotation axis 500.

Shroud side bottom surface 810 and shroud side end surface 1
10 gap, hub side bottom surface 910 and hub side end surface 12
The zero gap is always kept at the initial setting value even when the variable stator vane 100 rotates, and no contact occurs due to a decrease in the gap or loss due to an increase in the gap.

Additionally, the trailing edge 160 has counterbores 800 and 900.
If the gap is inside the gap, the flow that flows through the gap becomes difficult to flow to the downstream side, so the gap loss decreases.

The embodiment shown in FIGS. 3 to 5 is for the case where the rotation axis 500 is located at the center of the leading edge 150 and the rear edge 160, but the above-mentioned rotation axis 500 can be located anywhere. It is clear that the description remains valid.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing one variable stator vane and its support structure in a conventional turbomachine, Figure 2 is a diagram illustrating the locus when rotating this variable stator vane, and Figure 3 is a diagram illustrating the trajectory of the variable stator blade according to the present invention. FIG. 4 is a sectional view taken along line - in FIG. 3, and FIG. 5 is a sectional view taken along line - in FIG. 3. 100... variable stator blade, 110... shroud side end surface, 120... hub side end surface, 150... leading edge,
160... Trailing edge, 170... Shroud side shaft, 1
80...Hub side shaft, 200...Shroud, 23
0... Shroud inner wall, 300... Hub, 330
...Hub outer wall, 400...Drive lever, 500...
...Rotation axis center, 800...Spot face, 810...Shroud side bottom surface, 820...Spot face outer circumference, 900
...Counterbore, 910...Bottom surface, 920...Outer circumference of counterbore.

Claims (1)

[Scope of utility model registration request] In a turbomachine including a flow path having a guide wall on at least one of an inner circumferential side and an outer circumferential side of movable blades disposed radially, the guide wall has a surface opposite to an end surface of the movable blade. A turbomachine characterized by having a counterbore that is a plane perpendicular to the rotation axis.