JP3531290B2 - Blade shape measurement device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving blade shape measuring device for measuring a moving blade shape during operation.

[0002]

2. Description of the Related Art In rotary machines having a row of blades such as turbines and axial compressors, the moving blades constituting the row of blades are deformed by centrifugal force during operation, and this aerodynamic performance is changed. . Therefore, it is extremely important to measure the shape of the moving blade during acceleration / deceleration or during high speed operation in order to improve the performance of the device.

[0003]

Conventionally, in order to measure the shape of a moving blade during operation, for example, a pair of sensors are provided axially at intervals in a casing facing the tip (tip) of the moving blade, A means for measuring the twist of the tip portion with this sensor has been used. However, with such means, it was not possible to measure other than the tip portion, that is, the shape of the entire moving blade changing in the radial direction and its change. In addition, some people have predicted the rotating blade shape by computer simulation, but since the blade deformation is affected not only by centrifugal force but also by aerodynamic force, Accurate prediction was difficult.

The present invention was created to solve such problems. That is, an object of the present invention is to provide a moving blade shape measuring device capable of measuring the moving blade shape during acceleration / deceleration or during high speed operation in real time over the entire radial change.

[0005]

According to the present invention, a single reference position provided on a disk on which a plurality of moving blades are mounted, and a reference sensor for detecting the circumferential position of the reference position, A leading edge sensor that detects the circumferential position of each blade leading edge,
And a trailing edge sensor that detects a circumferential position of each trailing edge of the moving blade, and calculates the positions of the leading edge and the trailing edge of the moving blade from the detection signal of each sensor. Will be provided.

According to a preferred embodiment of the present invention, an arithmetic processing unit for calculating the inclination and the twist of the moving blade from the detection signals of the respective sensors is provided. Further, a traverse device for moving the leading edge sensor and the trailing edge sensor in the radial direction is provided. Also,
It is preferable that a plurality of leading edge sensors and a plurality of trailing edge sensors are provided at intervals in the radial direction.

[0007]

According to the structure of the present invention, a single reference position provided on the disk can be detected by the reference sensor, and the leading edge and the trailing edge of each rotor blade can be detected by the leading edge sensor and the trailing edge sensor. The circumferential position (angle) from the reference position of the edge can be detected. That is, the output signal of the reference sensor (referred to as the reference signal) is detected only once per one rotation of the disk, and the output signals of the leading edge sensor and the trailing edge sensor (referred to as the leading edge signal and the trailing edge signal) are the reference signals. During the signal, a number of times corresponding to the number of blades is detected. Therefore, each blade can be specified by the order of the leading edge signal and the trailing edge signal from the reference signal, and the leading edge and trailing edge due to centrifugal force or the like can be determined from the time difference between the leading edge signal and the trailing edge signal. The edge deformation can be calculated.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. In addition, in each figure, the same parts are denoted by the same reference numerals. FIG. 1 is an overall configuration diagram of a moving blade shape measuring device according to the present invention. In this figure, a moving blade shape measuring apparatus 10 of the present invention has a single reference position 12 provided on a disk 2 to which a plurality of moving blades 1 are mounted.
And a reference sensor 1 for detecting the circumferential position of the reference position 12.
3, a leading edge sensor 14 that detects the circumferential position of the leading edge 1a (leading edge) of each moving blade 1, and a trailing edge that detects the circumferential position of the trailing edge 1b (trailing edge) of each moving blade 1. The sensor 15 is provided. Further, the moving blade shape measuring apparatus 10 of FIG. 1 further includes an arithmetic processing unit 16 for calculating the inclination and twist of the moving blade 1 from the detection signals of the sensors 13, 14, 15; a display unit 17 and a storage unit 18. I have it.

In FIG. 1, the reference position 12 is, for example,
It is a front edge (or a rear edge) in the circumferential direction of a protrusion provided in the vicinity of the outer periphery of the disk 2 so as to project in the axial direction, and this position is detected by the reference sensor 13. The reference sensor 13 is a non-contact type position sensor attached to a fixed portion (not shown), and is preferably a reflection type optical sensor or a vortex sensor. With this configuration, the reference sensor 13
Output signal (reference signal) is 1 for each rotation of the disk 2.
Detected twice.

FIG. 2A is a partial plan view of FIG. 1 showing the positional relationship of each sensor. As shown in the figure, the leading edge sensor 14 and the trailing edge sensor 15 are arranged at a fixed angle Δθ1, Δθ2 from the reference position 12 in the circumferential direction. These angles Δθ1 and Δθ2 are not indispensable, and may be set at the same position, and either or both of Δθ1 and Δθ2 may be set to 0 (zero) as long as interference between sensors can be avoided. Further, the leading edge sensor 14 and the trailing edge sensor 15 are transmissive laser sensors in this embodiment, and detect the laser light 3 parallel to the axis line by the laser light source 19 in FIG.

The sensors 14 and 15 may be reflection type optical sensors or vortex sensors as long as they are non-contact type position sensors. With this configuration, as is apparent from FIG. 2A, the position (ON position) at which the leading edge sensor 14 starts to receive the laser light 3 coincides with the moving blade leading edge 1 a, and the trailing edge sensor 15 emits the laser light 3 The position (OFF position) at which the light reception ends is coincident with the moving blade trailing edge 1b, and the positions of the leading edge 1a and the trailing edge 1b can be accurately detected.

FIG. 2B shows the traverse mechanism shown in FIG.
FIG. As shown in this figure, the embodiment of FIG. 1 further includes a traverse device 20 for moving the leading edge sensor 14 and the trailing edge sensor 15 in the radial direction. In the traverse device 20, for example, a ball screw may be rotated by rotation of a pulse motor, and the sensors 14 and 15 may be attached to a ball nut screwed with the ball screw, or the sensor may be directly moved by a direct-acting cylinder.
The radial positions of the sensors 14 and 15 can be accurately detected from the input signal of the pulse motor, the rotation speed of the ball screw, the moving amount of the cylinder, and the like. In addition,
In this figure, 4 is a fixed portion such as an engine casing. With this configuration, the sensors 14 and 15 can be moved in the radial direction while maintaining the circumferential angles Δθ1 and Δθ2 from the reference position 12, and the radial positions can be accurately detected.

FIG. 3 is a partial side view similar to FIG. 2B according to another embodiment. In this embodiment, a plurality of leading edge sensors 14 and trailing edge sensors 15 are provided at radial intervals. Each sensor 14, 15 has a reference position 12
Are mounted at appropriate positions (for example, 10 mm) at positions where the circumferential angles Δθ1 and Δθ2 are held, and the respective detection signals are transmitted to the arithmetic processing unit 16 through the fixed portion 4. With this configuration, the sensor 14,
With 15 fixed, the positions of the leading edge 1a and the trailing edge 1b at different radial positions can be detected simultaneously.

FIG. 4 is a timing chart diagram schematically showing the output signals of the sensors 13, 14, 15 according to the embodiment shown in FIG. In this figure, the leading edge sensor 1
4 and the circumferential angle Δ of the trailing edge sensor 15 from the reference position 12
Although the case where θ1 and Δθ2 are zero is shown, the output signals of the respective sensors can be processed by the arithmetic processing unit 16 to make them zero.

In FIG. 4, the output signal (reference signal) from the reference sensor 13 is detected once for each rotation of the disk, and its time interval is T1. This time T1 is
It corresponds to one rotation of the disc (360 °), and shortens in inverse proportion to the rotation speed. Further, the output signals (leading edge signal and trailing edge signal) of the leading edge sensor 14 and the trailing edge sensor 15 are detected between the reference signals a number of times corresponding to the number of moving blades. Each blade can be identified by the order of the edge signal and the trailing edge signal. Further, the time intervals from the reference signal of the particular moving blade of interest are T2 and T3, respectively.
The ratio of the time intervals T2 and T3 to the time T1 indicates the angles of the leading edge 1a and the trailing edge 1b from the reference position.
Although the leading edge signal is based on the ON position and the trailing edge signal is based on the OFF position in this drawing, the present invention is not limited to this, and the leading edge and the trailing edge may be changed depending on the arrangement of each sensor. It is preferable to use a signal that is accurately detected as a reference.

That is, the reference position signal for one rotation once serves as a reference for the blade shape measurement, and the positions of the leading edge (leading edge) and the trailing edge (trailing edge) are angles based on this position. Shown. The leading edge and trailing edge detection sensors 14 and 15 detect the passage timing of the moving blade 1. Further, these sensors can detect the shape of each step surface of the blade by traversing in the radial direction.

The arithmetic processing unit 16 performs the following arithmetic processing, outputs the result to the display unit 17 and the storage unit 18, and displays and stores the result. In the timing chart of the signals obtained from the sensors 13 to 15 shown in FIG. 4, paying attention to a certain wing, the time interval of the reference position signal is set to T1.
, The time interval from the reference position to the leading edge detection is T2, and the time interval to the trailing edge detection is T
Then, the angle θL from the reference position to the leading edge and the angle θT from the trailing edge can be expressed by the following equations.

ΘL = (T2 / T1) × 360 ° θT = (T3 / T1) × 360 ° By continuously collecting this angle data during the acceleration of the rotating machine, the change of the blade shape can be detected. Further, by traversing the sensors 14 and 15 in the radial direction as shown by the dotted line in FIG. 2B, it is possible to detect the shape change of the entire cross section of the blade.

Therefore, each blade can be identified by the order of the leading edge signal and the trailing edge signal from the reference signal, and the time difference between the leading edge signal and the trailing edge signal leads to the centrifugal force or the like. Edge and trailing edge deformations can be calculated. The present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[0020]

According to the present invention described above, it is possible to measure the deformation of a moving blade during the operation of a rotary machine, which has been difficult to predict and actually measure, over almost all cross sections of the blade, and the measured value can be obtained. By feeding back to the design, it is possible to further contribute to improving the performance of the rotating machine.

Therefore, the blade shape measuring device of the present invention has an excellent effect that the blade shape during acceleration / deceleration or during high speed operation can be measured in real time over the entire radial change. .

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a moving blade shape measuring device according to the present invention.

FIG. 2 is a partial plan view (A) and a partial side view (B) of FIG.

FIG. 3 is a partial side view similar to FIG. 2B according to another embodiment.

FIG. 4 is a diagram schematically showing an output signal of each sensor according to the embodiment shown in FIG.

[Explanation of symbols]

1 moving blade 1a Leading edge 1b Trailing edge (trailing edge) 2 discs 3 laser light 4 fixed part 10 Moving blade shape measuring device 12 reference position 13 Reference sensor 14 Leading edge sensor 15 Trailing edge sensor 16 arithmetic processing unit 17 Display 18 storage 19 Laser light source 20 Traverse device

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Claims (4)

(57) [Claims] 1. A single reference position provided on a disk to which a plurality of moving blades are attached, a reference sensor for detecting a circumferential position of the reference position, and a circumferential position of each leading edge of each moving blade. A leading edge sensor for detecting and a trailing edge sensor for detecting a circumferential position of each moving blade trailing edge are provided, and the positions of the leading edge and the trailing edge of the moving blade are calculated from a detection signal of each sensor. And a blade shape measuring device. 2. The blade shape measuring device according to claim 1, further comprising an arithmetic processing unit that calculates the inclination and twist of the blade from the detection signals of the respective sensors. 3. The moving blade shape measuring device according to claim 1, further comprising a traverse device that moves the leading edge sensor and the trailing edge sensor in a radial direction. 4. The blade shape measuring device according to claim 1, wherein a plurality of leading edge sensors and trailing edge sensors are provided at intervals in a radial direction.