JPS62100629A - Torsion meter and shaft horsepower meter using same - Google Patents

Abstract

PURPOSE:To increase the reliability and the measuring accuracy of an instrument by detecting the displacement of the position of a light source caused by the torsion of a shaft to be measured by a position detector. CONSTITUTION:First and second flanges 8 and 8', respectively, are fixedly mounted to a rotating shaft 3 to be measured, the latter being apart from the former by a predetermined length L. Light is transmitted in a long cylinder mounted to the second flange 8' in an overhung manner. The light emitter from a laser 13 is converged on the surface of a one-dimensional position detector (PSD) 16 fixedly mounted to the fixed end of the long cylinder via an objective lens 14. A light source position displacement detecting circuit 17 processes the output of the PSD 16 and detects the positional displacement delta of the laser 13 generated with the torsion of the shaft 3 to be measured. A torsional angle calculator 37, processing positional displacement signals transmitted from a detecting circuit 17, computes the torsional angle theta of the shaft 3. A data thetais fed to a shaft horsepower meter 11 wherein the product of theta and the rotating speed of the shaft 3 is computed and a shaft horsepower P is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement of a torsion meter and a shaft horsepower meter using the same.

[Technical Background of the Invention] Conventionally, as shown in FIG. 6(a), internal combustion engines, steam engines, fft! The power generated by a prime mover 1 such as a T+ machine and the power consumed by a passive machine 2 such as an advance machine, a generator, a pump, and a blower are measured by power cutting. The power is proportional to the product of the rotational power factor and the rotational speed of the intermediate transmission shaft 3 that transmits the power. Therefore, since the rotational speed is measured by the rotating cylinder, the dynamometer can be used as either a rotational power factor meter (torque meter) that simply measures the rotational force of the shaft 3 or a torsion O of the shaft 3 (the sixth
It is often referred to as a torsion meter that measures figure (b)).

Many types of torsion meters and shaft horsepower Jt (torsion dynamometers) using torsion meters have been devised, designed and manufactured according to the method, principle, purpose, etc. of measuring the torsion θ of the shaft 3 (Japanese Marine (Refer to Journal of the Society of Mechanical Engineers, Vol. 16, No. 10). The general method for measuring the torsion θ of shaft 3 is as follows:
There are cases in which a special elastic shaft for measurement is used, and there are cases in which a measuring device 4 (Fig. 6 (a)) is attached to the outside of the actual power transmission shaft 3. Change the angle change O due to the twist between the distances into the position change amount of a certain radius (CC' = R・θ, cc' = δ, since O is small, δ years R・θ) (Figure 6 (b) ), this is measured mechanically, optically, electrically, or directly by converting it into a physical quantity that changes with torque, such as magnetostriction. The measurements obtained are used to measure the shaft horsepower required for the ship's contracted speed, which is necessary for the official commissioning, the ratio of engine fuel consumption, and information on the rules of similarity between the actual ship and the model ship that will be necessary for future designs. data, the ratio of fuel consumption required for economical operation of the engine necessary for operation management, the maximum efficiency of ship operation and the life of the hull and propeller shaft performance, the rationalization of operation management by measuring shaft output, etc. An extremely large amount of data can be obtained, including data on the vibration characteristics of the shaft system and torsional vibration.

The shaft horsepower when the prime mover 1 is transmitting power via the intermediate shaft 3 can be obtained by measuring the rotational speed N and rotational power factor (torque) T of the rotating shaft of the passive machine 2. The rotation power factor T is the torsion 0 (or δ) of the rotating shaft 3 that occurs in proportion to it.
is determined by measuring with a torsion meter. The twist θ is always accompanied by more complicated fluctuations due to interference with the passive device 2. Therefore, in order to obtain accurate shaft horsepower for steady-state operation at a constant rotational speed, it is necessary to use a torsion meter that can calculate the average value of torsion. For the official trial run, the hull is at constant speed and on axis 3.
The rotational speed N and rotational power factor T are independent and approximately constant.

Therefore, measure the rotational speed N using a tachometer.

The average value of the screw ha, which is proportional to the rotational power factor T, is determined using a torsion meter, and the shaft horsepower P is calculated from the following formula (6th
(See figure (b)).

P=π2・D4・G−N・θ/7.2・shi・10''
...(1) D: Shaft diameter (cm) G: Rigidity of shaft material (kg/cn?) N: Number of rotations of shaft (rpm) L: Torsion base shaft length (cnl) θ: Between L However, during general ocean voyages with wind and waves, the ship's body is shaken, and the rotational speed N of the rotating shaft 3 and the rotational power factor T interfere with each other in relation to the ship's maneuvering method, and are not independent of each other. do not have. Therefore, a highly accurate, durable, and inexpensive torsion meter that can measure temporal changes in the rotating speed N, rotating power factor T, and shaft horsepower P, which is the product of both (TXN), which fluctuates from moment to moment, and a shaft using the same. A horsepower meter was required.

Many torsion gauges are broadly classified into disc type, sleeve type, ring type, and other types based on their basic structure, and even relatively new types can be classified into more than 10 types. They are classified into mechanical, optical, and electrical types depending on the method of detecting and measuring twist. For example, FIG. 6(c) shows a sleeve-type torsion meter, and FIG. 6(d) shows an annular-type torsion meter, which is the base of the rotating transmission shaft 3. A disk 6, a sleeve 7, (or an annular ring 8.8') is fixed to each of the lengths 5 (lengths), and a screw 90 of the rotating shaft 3, that is, the disk 6 and a sleeve 7 (or an annular ring 8.
8') and a minute displacement δ (δ=R・θ).

They are measured by mechanical, optical, and electrical methods, respectively. In addition, with the progress of optical devices in recent years, optical measurement methods have been developed to directly measure the displacement δ without using reflection means.
It is becoming possible to measure the following. As a conventional example, the annular optical torsion meter shown in FIG. 6(d) will be briefly explained.

A metal ring 8.8 is attached to each of the base lines 5 of the intermediate transmission shaft 3 of length ■-.
' is fixed perpendicularly to the rotation axis QR1, and a light source S and a concave mirror M with a radius of curvature are provided thereon to face each other, and lenses V,
A prism G and a film F are each provided at $*3, O is the center of curvature, C is the mirror center, and therefore ○C is the main axis, which is fixed so that it is parallel to the center line QR of the rotation axis of shaft 3. It is. Straight lines X1 and X2 that pass through ○ and are perpendicular to the main axis OC
If a slit-shaped light gS is placed at any point on the extension of
A mirror image P that is symmetrical with respect to the point and of the same size is obtained.

Now, if the shaft 3 is a propeller rotating clockwise, the screw J is turned in the opposite direction, so the concave mirror M is a straight line X1 passing through the light source S.
．． By displacing δ in parallel to X2, the position of M', that is, the main axis OC, moves to ○゛C'. Therefore, the image of the light source S is O'
This displacement 2δ, which is clearly PP' = 2δ (the length of the base line 5 is about 0.5 mm at 1 m), is magnified with a lens V and passed through a special prism G to the rotation axis. An image P of P' can be formed on the plane of the filter lzF, which rotates about axes x', x', which are orthogonal to the center line QR of 3. In this way, the twist θ appears on the surface of the film F entirely by an optical method, so the change in the rotational power factor T of the shaft 3 during rotation is due to the rotation of the film F in the direction of the arrow as the shaft 3 rotates. is obtained continuously by Then, a pair of identical optical systems is installed symmetrically on both sides of the outer peripheral surface of the shaft 3, and the correct zero point is always determined from the average value of both.
This excludes the influence of the deflection of I13; four considerations should be taken. Both ii made by rotating the rotating shaft 3 once left and right under zero load condition! The average value of B, that is, the static zero line is recorded on the surface of the film 17 as a reading Δ0 under no load. Next, the change in torsion due to load is recorded as a dynamic zero line, and the average value for one rotation is set as Δ'. From this, the difference between the two is Δ′−Δ. =Δ
is the twist corresponding to the average rotational power factor. Therefore, if the rotational speed of the rotating shaft 3 at this time is N, the shaft horsepower P can be obtained from the following equation.

P=k・Δ・N (2) k: Torsion meter constant Δ: Average displacement of image on film surface (-m) N: *t
Rotational speed of J (rpm) [Problems with the background art] By the way, in the above-mentioned toric torsion meter that magnifies the relative minute displacement δ using an optical method, the basic axis length is long and it is necessary to equip it with devices. The space required for this process was large, making it difficult to adjust and install the device. Furthermore, in the case of a device using a sleeve or the like, since the mechanical elements of the device are installed, the mass distribution thereof becomes uneven with respect to the rotation axis and is subjected to inertial force such as centrifugal force. Furthermore, since the light source section, the reflecting means, etc. have large masses, they are susceptible to vibrations from the outside world, which increases errors. Furthermore, due to the equipment, the width of the slit image of the light source became too wide, making it impossible to increase the optical magnification. Furthermore, since the rotation speed of the shaft was calculated as an average value between - and cruising, the error was large.

Moreover, depending on the torsion meter, there are many drawbacks such as the fact that shaft horsepower results cannot be obtained until after the test run is completed and the engine is stopped.9 [Object of the Invention] The present invention was made in view of the above-mentioned problems. The reliability of the device is high because the optical system is simple and easy to adjust, and the optical system has a large magnification ratio and high precision, making it possible to measure short measured axes, and the optical path is shielded. Therefore, it is an object of the present invention to provide a torsion gauge and a shaft horsepower meter using the torsion gauge, which can easily prevent light from entering from the outside, and which is less likely to be contaminated because it has a dust-proof structure.

[Summary of the invention] According to the torsion meter of the present invention to achieve this object,
a first flange fixed to the measured shaft; and a second flange fixed to the measured shaft at a predetermined distance from the first flange.
a flange, a long tube attached to the second flange in a cantilevered manner, a light source attached to the first flange and opposed to the non-fixed end of the long tube, and a light source from the light source. an objective lens fitted into the long tube so that the emitted light is converged on the fixed end of the long tube; a flexible pipe joining the light source and the non-fixed end of the long tube;
a position detector attached to the fixed end of the long tube so that the light receiving surface is at the focal position of the objective lens; and a position detector that processes the output signal of the position detector to detect the distortion caused by the torsion of the axis to be measured. a light source position displacement detection circuit that detects a position displacement of the light source; and a light source position displacement detection circuit that detects a position displacement of the light source;
and a torsion angle calculator that processes the generated positional displacement signal to calculate the torsion angle of the shaft to be measured.

According to the shaft horsepower meter of the present invention to achieve this purpose,
a first flange fixed to the measured shaft; and a second flange fixed to the measured shaft at a predetermined distance from the first flange.
a flange, a long tube attached to the second flange in a cantilevered manner, a light source attached to the first flange and opposed to the non-fixed end of the long tube, and a light source from the light source. an objective lens fitted into the long tube so that the emitted light is converged on the fixed end of the long tube; a flexible pipe joining the light source and the non-fixed end of the long tube;
A position detector is attached to the fixed end of the long tube so that the light receiving surface is at the focal position of the objective lens, and the output signal of the position detector is processed to detect wrinkles in the shaft to be measured. a light source position displacement detection circuit that detects a positional displacement of the light source caused by the light source; and a torsion angle calculator that processes a position displacement signal transmitted from the light source position displacement detection circuit to calculate a torsion angle of the measured axis. , a shaft rotation needle that measures the rotation speed of the shaft to be measured; and a shaft horsepower that calculates shaft horsepower based on the rotation speed measured by the shaft rotation needle and the torsion angle calculated by the torsion angle calculator. It is equipped with a calculator.

[Embodiments of the Invention] Preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 and 2. The torsion meter 10.10' of the present invention includes a first flange 8, a second flange 8', a long cylinder 15, and a point light source semiconductor laser (hereinafter referred to as laser) 13.13' as a light source.
(Here, 13' indicates the laser at the apparent position of laser 13).

Objective lens 14. Bellows as a flexible pipe (not shown), one-dimensional position detector as a position detector (
(hereinafter referred to as PSD) 16, light source position displacement detection circuit 17,
Torsion angle calculator 371 oscillator 18, modulator 19. It is formed by a demodulator 25 and antenna systems 2o and 20'.

The first flange 8 is fixed to a rotating shaft 3 to be measured, such as a power transmission shaft of a ship. The second flange 8' has a predetermined length from the first flange 8.

For example, it is fixed to the shaft 3 to be measured at a distance of about 300 a+m. The long tube 15 is attached to the second flange 8' in a cantilevered manner, and light propagates inside.

The laser 13 is attached to the first flange 8 and is opposed to the non-fixed end 38 of the long tube 15. The objective lens 14 is.

The emitted light from the laser 13 is transmitted to the fixed end 3 of the long tube 15.
P S D ], fixed at 9, is a convex lens fitted into the long tube 15 so as to converge on the surface of 6.

The bellows (not shown) includes the laser 13 and the long cylinder 15.
This is a light shielding member that joins the non-fixed end 38 of. PSD16
is attached to the fixed end 39 of the long tube so that the light receiving surface is located at the focal point of the objective lens 14. The light source position displacement detection circuit 17 processes the output signal from the PSD 16 and detects the position displacement δ of the laser 13 that occurs as the shaft 3 to be measured is screwed. The torsion angle calculator 37 processes the position displacement signal transmitted from the light source position displacement detection circuit 17 to calculate the torsion angle θ of the shaft 3 to be measured. The oscillator 18 is
It generates a carrier wave.

The modulator 19 modulates the carrier wave with the position displacement signal. The antenna system 20 is for transmitting modulated waves, and the antenna system 20' is for receiving the modulated waves. The demodulator 25 demodulates the modulated wave received by the antenna system 20' to obtain the position displacement signal.

As shown in FIG. 2, the shaft horsepower meter 11 of the present invention employs the torsion meter 10, 10' as is, and also includes a shaft rotation meter 26 and a shaft horsepower calculator 27.

The shaft tachometer 26 measures the rotational speed N@ of the shaft 3 to be measured. The shaft horsepower calculator 27 includes the shaft rotation meter 26.
The shaft horsepower P is calculated based on the rotational speed N measured by the rotation speed N and the torsion angle O calculated by the torsion angle calculator 37.

The operation of the torsion meter of the present invention constructed as described above and the shaft horsepower meter using the same will be explained based on FIGS. 1, 2, and 3. The principles of measuring torsion and shaft horsepower are as follows.

In other words, the displacement δ between the light receiving position on the receiving surface of the emitted light when the rotating measured shaft 3 is not loaded and the light receiving position on the receiving surface of the emitted light when the rotating measured shaft 3 is loaded is determined by the torsion of the rotating measured shaft 3, that is, the rotation. Power factor (torque) is proportional to T. Therefore, by detecting this displacement and extracting it as an electrical signal, the torsion angle O can be determined. By calculating the product of this and the rotation speed (rotation speed N) of the shaft 3 to be measured at that time, the shaft horsepower P can be determined.

First, in the torsion meter 10 shown in FIG.
The light is received by the PSD 16 located at a predetermined distance b, that is, the focal length of the lens 14, from the light receiving position IQ point. Then, while the shaft 3 to be measured is rotating in the direction of the arrow, the initial point P of the beam is displaced by δ to point P' according to the torsion θ of the shaft 3 to be measured, so that the light receiving position is δ・
The light is received at point Q', which is displaced by b/a. and P
Displacement X (of the light receiving position in SD16 from electrode 23
position displacement signal V o-1-K-x proportional to Fig. 3)
+ (K is a constant) is obtained by the light source position displacement detection circuit 17.

That is, as shown in FIG. 3, the PSD 16 consists of a one-dimensional light receiving section and three electrodes 22 to 24, and the incident light is applied to a position proportional to the screw 90 of the shaft 3 to be measured. If the distance between the electrodes 22 and 23 is α (resistance value R-α, R is the resistance value per unit length), and the distance from the electrode 23 to the receiving position of the incident light is X (resistance value R-x). , the incident energy of the light is expressed as a photocurrent proportional to this, and the light receiving position x
The voltage is divided in inverse proportion to the resistance value Rx from 22 to 23, and taken out from the electrodes 22 and 23. That is, the photocurrent generated by the incident light is I. , ffi pole 22.23
Assuming the currents taken out from Ia and Ib, Ta=(Q
-x)・Io/Q, It+=x−Ia/Q.

and) the sum of the calculated Ia and Ib (Ia + Ib),
Ratio of difference (Ia-Ib) (Ia-Chob)/(Ia+Chob)
is calculated, and the output VO is (Ia Ib)/(Ia+
Ib) = 1- to -x, (K = 2/Q). In this way, a positional displacement signal having linearity proportional to the incident position of the light is obtained regardless of the incident energy.

Therefore, as shown in FIG. 2, a carrier wave generated from an oscillator 18 is modulated by a modulator 19 using the position displacement signal. This modulated wave is transmitted from the antenna system 20 toward the torsion meter 10', and the antenna system 2 of the torsion meter 10'
0' and demodulated by demodulator 25. Further, a twist angle is calculated in a twist horn output circuit 37. This signal is a signal regarding the torsion O (torque T proportional to the torsion θ), and this signal is input to the analog display 28 and the digital recorder 29, and the respective data are displayed.

The signal of the torsion θ (torque T proportional to the torsion θ) is input to the shaft horsepower calculator 27 of the shaft horsepower meter 11, and the rotational speed N is measured by the shaft tachometer 26 installed separately on the shaft 3 to be measured.
The signal is input to the shaft horsepower calculator 27. Then, the shaft horsepower calculator 27 calculates the product TXN of the torque T and the rotational speed N, and outputs a temporal change in the shaft horsepower P. The data of the shaft horsepower P and rotation speed N regarding the shaft 3 to be measured thus obtained are continuously displayed on the analog display 30, 32. and are displayed and recorded on digital recorders 31 and 33, respectively.

In this case, power is supplied from the torsion meter 10' to the torsion meter 10, which rotates with the rotation of the shaft 3 to be measured.
This is done via a slip contact 35.

Another preferred embodiment of the present invention will be described in detail with reference to FIGS. 4 and 5. The torsion gauge 10.10' of the present invention includes a first flange 8, a second flange 8', a long cylinder 15, and a point light source semiconductor laser (hereinafter referred to as laser) 13 as a light source.
, a reflecting mirror 36 as a reflecting means, an objective lens 14, a bellows as a flexible pipe (not shown), and a one-dimensional position detector (hereinafter referred to as PSD) 1 as a position detector.
6. Light source position displacement detection circuit 17, twist angle calculator 37° oscillator 18. Modulator 19. Demodulator 25. Aerial system 20.
20', and is different from the previous embodiment in that a reflecting mirror 36 is provided and the shape of the long tube 15 is different.

The long tube 15 is attached to the second flange 8' in a cantilevered manner and is bent in an L-shape near the non-fixed end, allowing light to propagate inside and be reflected! I36 indicates that the emitted light from the laser 13 reaches the fixed end 39 of the long tube 15.
The bent portion 40 of the long tube 15 is bent so as to be reflected toward the
For example, it is arranged at an angle of 45 degrees with respect to the optical axis.

In this way, the vicinity of the non-fixed end of the long axis 15 is bent into an L-shape, and the reflecting mirror 36 is disposed at the bent portion 40 at an angle of 45 degrees, so that even if the shaft 3 to be measured is expanded or contracted in the axial direction, Even if this happens, the optical path length from the laser 13 to the objective lens 14 will not change.

As a result, there is no need to worry if an error due to the expansion and contraction of the J1g constant shaft 3 is added to the measured value of the torsion angle of the shaft 3 to be measured.

Furthermore, since the configuration is as described above, the positional displacement δy (fifth
(Fig. 5), the positional displacement δX (Fig. 5) of the laser 13 in the X direction due to the expansion and contraction of the measured axis 3 is also received on the PSD 16 as the light receiving position displacement δX-b/d from the optical axis. It has become so.

Therefore, by using a two-dimensional PSD in the X direction and the X direction, the amount of expansion and contraction of the shaft 3 to be measured can also be measured.

[Effects of the Invention] As is clear from the above embodiments, according to the torsion meter of the present invention and the shaft horsepower meter using the same, the light source is attached to the first flange fixed to the shaft to be measured, and the long A fixed end of the long tube is attached to a second flange fixed to the shaft to be measured so that the non-fixed end of the tube faces the light source,
An objective lens is fitted at a position separated by a focal length from a light receiving surface of a position detector attached to the fixed end of the long tube.

A flexible pipe connects the light source and the non-fixed end of the long tube, and the position detector captures the positional displacement of the light source that occurs as the shaft to be measured is torsion, and calculates the torsion angle and shaft horsepower. Because of this configuration, the optical system is simple and easy to adjust, making the device highly reliable.The optical system has a large magnification and high precision, making it possible to measure short measured axes, and the optical path is not blocked. Since it has a dust-proof structure, it can easily prevent light from entering from the outside, and it has the effect of being less likely to be contaminated.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the optical system of the torsion meter according to the present invention;
The figure is a block diagram of a torsion meter according to the present invention and a shaft horsepower meter using the same, FIG. 3 is an explanatory diagram of the position detector and light source position displacement detection circuit of the torsion meter according to the present invention, and FIG.
) is a side view of the optical system of the torsion meter shown as another embodiment of the present invention, FIG. 4(b) is a plan view of the optical system of the torsion meter shown as another embodiment of the present invention, and FIG. 6 is a perspective view of an optical system of a torsion meter shown as another embodiment of the present invention, and FIG. 6(a) is an explanatory diagram showing the relationship between a prime mover and a passive device connected via an intermediate transmission value. FIG. 6(b) is an explanatory diagram showing the screw 9 of the intermediate transmission shaft,
FIG. 6(c) is an explanatory diagram showing a conventional sleeve-type torsion meter, and FIG. 6(d) is an explanatory diagram showing a conventional optical ring-type torsion meter and a shaft horsepower meter using the same.

Claims (1)

[Claims] 1. A first flange fixed to the shaft to be measured;
a second flange fixed to the measured shaft at a predetermined distance from the flange; a long tube attached to the second flange in a cantilevered manner; a light source facing the non-fixed end of the tube; an objective lens fitted into the long tube so that emitted light from the light source is converged on the fixed end of the long tube; the light source and the long tube. a flexible pipe that joins the non-fixed ends of the tube, a position detector attached to the fixed end of the long tube so that the light-receiving surface is aligned with the focal position of the objective lens, and a position detector that processes the output signal of the position detector. a light source position displacement detection circuit that detects a positional displacement of the light source that occurs due to the torsion of the measured shaft; and a light source position displacement detection circuit that processes a position displacement signal transmitted from the light source position displacement detection circuit to determine the torsion angle of the measured shaft. A torsion meter characterized by comprising a torsion angle calculator for calculating. 2. A reflection means is provided at the bent portion of the long tube so that the vicinity of the non-fixed end of the long tube is bent in an L-shape, and the emitted light from the light source is reflected toward the fixed end of the long tube. A torsion gauge according to claim 1, wherein the torsion gauge is provided. 3. A first flange fixed to the shaft to be measured, and the first flange fixed to the shaft to be measured;
a second flange fixed to the measured shaft at a predetermined distance from the flange; a long tube attached to the second flange in a cantilevered manner; a light source facing the non-fixed end of the tube; an objective lens fitted into the long tube so that emitted light from the light source is converged on the fixed end of the long tube; the light source and the long tube. a flexible pipe that joins the non-fixed end of the tube, a position detector attached to the fixed end of the long tube so that the light receiving surface is aligned with the focal position of the objective lens, and a position detector that processes the output signal of the position detector. a light source position displacement detection circuit that detects a positional displacement of the light source that occurs due to the torsion of the measured shaft; and a light source position displacement detection circuit that processes a positional displacement signal transmitted from the light source position displacement detection circuit to detect the torsion of the measured shaft. a torsion angle calculator for calculating the angle; a shaft rotation meter for measuring the rotation speed of the shaft to be measured; and a rotation speed measured by the shaft rotation meter and the torsion angle calculated by the torsion angle calculator. A shaft horsepower meter comprising: and a shaft horsepower calculator for calculating shaft horsepower. 4. A reflection means is provided at the bent portion of the long tube so that the vicinity of the non-fixed end of the long tube is bent in an L-shape, and the emitted light from the light source is reflected toward the fixed end of the long tube. The shaft horsepower meter according to claim 3, which uses a torsion meter provided.