JPH08143272A - Crane hook with optical fiber gyro - Google Patents

Abstract

PURPOSE: To measure a swing angle stably and with high precision by realizing high precision measurement by fitting to a hook an optical fiber gyro that acts as a swing angle sensor for measuring the swing angle of a suspended load. CONSTITUTION: An optical fiber gyro 11 that acts as a swing angle sensor is fitted to the hook 1 of a crane 6, and the hook 1 is made to be a hook with an optical fiber gyro, and the swing angle of the hook 1 is measured, and swing angle data are measured on the crane 6 through the medium of the cable 12 of the optical fiber gyro, and connection to a manufacturing device is realized. This swing stop controller measures the swing angle of the hook 1 by means of the swing angle sensor (the optical fiber gyro 11) to detect a swing angle and conducts feedback control to restrain the swing angle of the hook 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hook for a crane equipped with an optical fiber gyro. The present invention relates to a technique for detecting a deflection angle with high accuracy.

[0002]

2. Description of the Related Art A velocity pattern at the time of acceleration / deceleration of a crane or a trolley is obtained from a motion equation relating to a deflection angle of a suspended load,
In the steady rest control device for a crane that controls the steady rest of a suspended load based on the speed pattern, conventionally, means for measuring the swing angle of the suspended load has been disclosed in JP-A-58-026792 and Japanese Utility Model Laid-Open No. 4-138083. As disclosed in the publications and the like, the main technique is to measure the displacement of the wire rope on the trolley side (hereinafter referred to as "prior art 1"). As shown in FIG. 8, in Prior Art 1, there is a problem that the displacement of the wire rope is small compared to the measurement on the suspended side of the wire rope, and the resolution cannot be large when converted to the deflection angle, and the deflection angle with high accuracy is obtained. Was difficult to detect. FIG.
In, 2 is a suspended load, 3 is a potentiometer, and 10 is a wire rope.

A method of recognizing an image from a trolley by attaching a light emitting body to a hanging tool for holding a suspended load, a suspended load, or the like, which is hooked to the lower portion by a hook, is disclosed in Japanese Utility Model Publication No. 1-176680. It is disclosed in Japanese Patent Application Laid-Open No. 4-201988 and Japanese Patent Application Laid-Open No. 62-244893 (hereinafter referred to as "Prior Art 2"). In the prior art 2, in a crane traveling in a long range, image processing is affected by ambient light, and it is difficult to perform stable and highly reliable measurement. In FIG. 9, 1 is a hook, 13 is a hanging tool for holding a hanging load (not shown), 10 is a wire rope,
Reference numeral 4 is an image processing device, and 5 is a light emitting diode.

[0004]

Since the conventional deflection angle detecting device is constructed as described above, it is possible to measure disturbance in a region where the displacement of the rope length is small and the deflection angle resolution is poor, or to use the image processing for disturbance. There was a problem in terms of accuracy and reliability due to optical interference.

An object of the present invention is to improve the steady rest control of a crane equipped with a steady rest control device for the purpose of controlling the steady rest of a suspended load, and enables extremely sensitive measurement.
An object of the present invention is to provide a hook for a crane with an optical fiber gyro, which can measure the deflection angle with high accuracy and stability without being affected by the surrounding environment.

[0006]

[Means for Solving the Problems] We have conducted extensive studies to solve the above problems. As a result, in a crane in which the hook is suspended by the wire rope, a double pendulum having a pendulum shaft is provided at two points, the upper end of the wire rope and the hanging point of the suspended load hooked on the hook. However, the deflection angle is measured at the hanging point θ _{2 of the} suspended load.
Instead, the deflection angle θ ₁ should be measured with the upper end of the wire rope as the axis, the deflection angle sensor should be attached to the hook to measure the deflection angle θ ₁ , and the deflection angle measurement should be performed using an optical fiber gyroscope. We have found that a formula sensor is suitable. The present invention was made based on the above findings.

The present invention is a hook suspended from a crane having a steady rest control device for controlling steady rest of a suspended load via a wire rope, wherein the hook has a swing angle of the suspended load. It is characterized in that an optical fiber gyro is attached as a deflection angle sensor for measurement.

[0008]

[Operation] An optical fiber gyro (rate gyro etc.) is attached to the hook as a deflection angle sensor. The mass of this hook for crane with optical fiber gyro is m ₁ ,
The weight of the hanging device under the hook and the suspended load (suspended device + suspended load) is m ₂
Then, the wire rope, the hook, the suspending tool, and the suspending load (the suspending tool and the suspending load are fixed) form a double pendulum as shown in FIG. Considering the model of the double pendulum shown in FIG. 10, the equations of motion of θ ₁ and θ _{2 in} this case are the following equations (1) and (2). However, m ₁ : mass of the hook m ₂ : mass of the hanger and load under the hook g: gravitational acceleration α: crane thrust

[0009] Can be

[0010] This is the case of feedback, and it becomes possible to suppress both θ ₁ and θ ₂ .

On the other hand, an optical fiber gyro (a deflection angle sensor) is provided on the secondary pendulum side, that is, on a suspending tool or a suspended load under the hook.
FIG. 11 shows an example in which is provided and θ ₂ is detected and feedback control is performed. In FIG. 11, the vertical axis represents shake and the horizontal axis represents time. As indicated by the solid line in FIG. 11, it can be seen that the shake does not easily settle by diverging without following the model indicated by the dotted line. In FIG. 11, FB: θ ₂ , gain: −2, θ ₁ : trajectory. Therefore, the fiber optic gyro should be attached to the hook.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a front view showing a hook to which an optical fiber gyro according to an embodiment of the present invention is attached, and FIG.
FIG. 4 is a front view of the crane, FIG. 3 is a front view showing a mounting position of equipment constituting a steady rest control device of the crane including the hook of the present invention, and FIG. 4 is a plan view.

For example, when a coil is hoisted by a crane, the lifter serves as a hoisting tool and the coil serves as a hoisting load. An optical fiber gyro 11 as a deflection angle sensor is attached to the hook 1 of the crane 6 to form a hook with an optical fiber gyro of the present invention, and the deflection angle θ ₁ of the hook ₁ (see FIG. 10) is measured. In FIG. 1, 14 is a stopper. No special design is required for the hook to attach the fiber optic gyro. It suffices that a general crane hook be provided with a stand so that the optical fiber gyro can be fixed. The cable 12 of the optical fiber gyro 11 is the wire rope 1
Like 0, it is rolled up on trolley 7. Therefore, it is necessary to install the cable reel on the trolley 7.

The deflection angle data can be measured on the crane 6 through the cable 12 of the optical fiber gyro and can be connected to the control device. The control device has a configuration as shown in FIG. This steady stop control device measures the swing angle of the hook by a swing angle sensor (optical fiber gyro) that detects the swing angle, and performs feedback control for suppressing the swing angle of the hook. As a deflection angle sensor, there is a mechanical vertical gyro from the past, but in the optical fiber gyro, the mechanical vertical gyro has a coordinate reference when the suspended load rotates,
There is no defect such as an error in the motor control of traverse and travel, and the deflection angle can be measured extremely accurately.

FIG. 6 is a block diagram showing the control system of the present invention. The deflection angle sensor consisting of an optical fiber gyro is connected to a deflection angle control controller via a cable reel, and inputs the deflection angle of a crane hook. At this time, the deflection angle is measured with high accuracy without being affected by fluctuations due to the environment (such as ambient light and water vapor). At the same time, if the deflection angle feedback control as described below is performed, the primary deflection can be stably controlled without being affected by the secondary deflection, and the secondary deflection can be controlled.

When the crane model is a runout angle model with only primary runout and the crane process is a model considering up to secondary runout, the characteristic equation of the transfer function of the input μ with respect to the primary runout θ _{1 is the} following equation (3). Indicated by.

The requirement for a stable root is K <0.
(Negative feedback). The necessary and sufficient condition for being a stable root is that all the coefficients of (−K) ² · m ₂ (m ₁ + m ₂ )> 0 S ⁿ are positive. Therefore, stability is guaranteed at any value of -K> 0.

FIG. 7 is an example of performing feedback control according to this embodiment, and is a graph showing a trajectory of steady rest control in a system in which a secondary shake exists, in which the vertical axis represents shake and the horizontal axis represents time. As shown by the solid line in FIG. 7, it can be seen that the shake is prevented by following the model of the dotted line. In FIG. 7, F
_{B 1: θ 1, K 2} : -5, θ 1: trajectory.

On the other hand, an optical fiber gyro is provided on the secondary pendulum side outside the scope of the present invention, that is, on the hanging tool or the suspended load under the hook, and the secondary shake θ ₂ component is measured by the shake angle sensor,
The characteristic equation when θ ₂ is controlled is as shown by the following equation (4).

As shown in the equation (4), the coefficient of S ³ becomes 0, and the stability condition is not satisfied. Therefore, when performing crane steady rest control, it is necessary to attach an optical fiber gyro (sway angle sensor) to the hook and feed back only the primary runout θ ₁ , which is a lifting device (hanging load) under the hook.
There is no physical meaning to attach the deflection angle sensor to.

[0022]

As described above, according to the present invention, the optical fiber gyro is used as the deflection angle sensor, and the optical fiber gyro is attached to the hook so that the optical fiber gyro attached to the hook measures the primary deflection component of the crane. Therefore, the primary deflection angle can be measured with high accuracy without being affected by the environment, and if the feedback control as shown in FIG. 6 is performed, a stable deflection angle control system can be provided, and an extremely high precision and stable crane can be provided. A steady rest control is obtained, thus providing an industrially useful effect.

[Brief description of drawings]

FIG. 1 is a front view showing a hook with an optical fiber gyro according to one embodiment of the present invention.

FIG. 2 is a front view of a crane to which the hook with an optical fiber gyro of the present invention is applied.

FIG. 3 is a front view showing a mounting position of equipment constituting the steady rest control device of the crane including the hook with the optical fiber gyro of the present invention.

FIG. 4 is a plan view showing a mounting position of equipment constituting the steady rest control device of the crane including the hook with the optical fiber gyro of the present invention.

FIG. 5 is a block diagram showing the system configuration of a steady rest control device for a crane including an optical fiber gyro hook according to the present invention.

FIG. 6 is a block diagram showing a control system of a steady rest control device for a crane including a hook with an optical fiber gyro according to the present invention.

FIG. 7 is an example of performing feedback control according to the present embodiment, and is a graph showing a trajectory of steady rest control in a system in which secondary shake exists.

FIG. 8 is a schematic front view for explaining deflection angle detection by conventional wire displacement measurement.

FIG. 9 is a schematic front view illustrating a shake angle detection by performing image processing on a light emitting body of a conventional hanging tool.

FIG. 10 is a schematic front view illustrating the principle of a double pendulum.

FIG. 11 is an example of performing feedback control for comparison, and is a graph showing a trajectory of steady rest control in a system in which secondary shake exists.

[Explanation of symbols]

 1: Hook 2: Suspended load 3: Potentiometer 4: Image processing device 5: Light emitting diode 6: Crane 7: Trolley 8: South side wheel 9: North side wheel 10: Wire rope 11: Optical fiber gyro (deflection angle sensor) 12: Cable 13 : Lifting tool 14: Retainer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Osamu Yamaguchi 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nihon Steel Pipe Co., Ltd. (72) Inventor Koichi Abe 1 Ono-cho, Tsurumi-ku, Yokohama-shi Kanagawa Industrial Co., Ltd. (72) Inventor Hiromi Makita 1 Ono-cho, Tsurumi-ku, Yokohama-shi, Kanagawa Steel tube electrical equipment Industrial Co., Ltd. (72) Inventor Kimio Shiozawa 1879 Okyu Iida, Nagano Prefecture Tamagawa Seiki Co.

Claims (1)

[Claims] 1. A hook suspended from a crane equipped with a steady rest control device for controlling steady rest of a suspended load via a wire rope, wherein the swing angle of the suspended load is measured on the hook. A crane hook with an optical fiber gyro, which is equipped with an optical fiber gyro as a deflection angle sensor.