CN108557648A - A kind of two-electron atom bridge crane panning angle measuring device and measurement method based on capacitance detecting - Google Patents

Abstract

The invention proposes a device and method for measuring the swing angle of a double-sling bridge based on capacitance detection, which includes lightweight pendulums installed perpendicular to each other, a variable capacitor, a signal processing device, and a swing angle synthesis computer. When the hanging rope swings, it drives the rotating shaft to rotate, causing the relative area of the capacitor to change. The obtained information is sent to the capacitance measuring circuit, converted into an electrical signal, sent to the signal processing device, and then sent to the swing angle synthesis computer to obtain the load of the two spreaders. swing angle information. The invention has the advantages of simple structure, high precision, convenience and the like.

Description

A device and method for measuring the swing angle of a double-slinger bridge based on capacitance detection

Technical field:

The invention relates to a measuring device, in particular to a measuring device and a measuring method for a double-slinger bridge suspension angle based on capacitance detection.

Background technique:

Double-slinger bridge crane is a kind of lifting equipment for port container yards. It has two lifting spreaders, which can lift two 40-foot or four 20-foot containers at a time, which is different from the traditional single-slinger bridge. Compared with cranes, the loading and unloading efficiency of containers has been greatly improved. However, due to the complex structure of this large-span double-lift double-sling bridge crane, various working methods and coupling, and the fact that there are wind loads in the real environment In addition, the movement of the trolley will cause the sling to sway, which brings great difficulty to the detection of the swing angle of the spreader.

One of the key problems in the anti-sway control of bridge cranes is the detection of the swing angle. Most of the existing detection devices for the swing angle of bridge cranes are designed for single-sling bridge cranes. Most of these detection devices can be divided into contact type and non-contact type. Measurement. An existing contact pendulum angle detection device uses a lightweight pendulum to drive a code disc to rotate. This measurement method is not accurate enough to affect the measurement effect, and the detection components are easy to wear and inconvenient to maintain; the non-contact pendulum Angle detection devices often use laser angle meters, which have high requirements on the working environment and are expensive. At the same time, the existing bridge crane operators often obtain the swing condition by visually observing the spreader and the load, which has low accuracy and potential safety hazards, which affects work efficiency and work quality.

Invention content:

The swing angle measuring device involved in the present invention utilizes the characteristic that the capacitance value changes with the capacitance facing area, and solves the problems of detection of swing angle direction and size, swing angle information processing and display of a double-lift double-slinger bridge crane .

In order to achieve the above object, technical scheme of the present invention is as follows:

A device for measuring the swing angle of a bridge crane with double spreaders based on capacitance detection, the device is arranged on the trolley structure, the trolley mechanism is arranged on the cart mechanism, the cart mechanism includes a bridge crane cab, the A pair of hoisting motors are provided on the trolley mechanism, each hoisting motor includes a rotating shaft, and the rotating shaft is connected to the spreader through a sling, and its characteristic is that a double-sling bridge suspension angle detection device based on capacitance detection is arranged; the described The swing angle detection device includes: a pair of signal processing devices, which are symmetrically arranged on the top of the trolley mechanism; a swing angle synthesis computer, which is arranged in the cab and connected to the pair of signal processing devices respectively;

The main body of the pendulum angle detection device described is a black box, which includes a semi-cylindrical side-type capacitor positive plate connected to one end of the lightweight swing frame, and two quarter-cylindrical side-type capacitor negative plates fixed on the black box. At the bottom of the box, the two ends of the capacitor are connected to the capacitance measuring circuit through wires.

The signal processing device includes a voltage amplifier, a rectification filter, and an A/D converter. The input end of the voltage amplifier is connected to the capacitance measurement circuit, and the output end of the voltage amplifier is connected to the rectification filter and the A/D converter in turn, and then output Give the pendulum a synthetic computer.

A method for measuring the swing angle of a double-slinger bridge based on capacitance detection, comprising the following steps:

Step 1: Set the initial position of each component, and use this as the initial reference position. The setting process is as follows: first let the two spreaders of the double-sling bridge crane hang down naturally, and at this time the suspension rope has no swing angle. The lightweight swing frame and the positive plate of the capacitor plate have no rotation; the signals obtained by the two sets of swing angle detection devices are used as the initial reference value for the calculation of the swing angle, and the capacitance value received at this time indicates that the swing angle in the current axial direction is 0 ;

Step 2: The driver's cab sends out the operation instructions of the bridge crane, and the bridge crane controls the operation of the corresponding spreader according to different operation commands, and the hanging ropes connected to each spreader swing;

Step 3: The swing of the sling will drive the rotation of the lightweight pendulum to cause the rotation of the positive plate of the capacitor, causing the change of the facing area, causing the change of the capacitance value of the first capacitor or the second capacitor, and the voltage obtained by the capacitance measurement circuit The signal is transmitted to the signal processing device;

Step 4: The signal processor receives the electrical signals from the x and y directions for processing, amplifies, filters, A/D converts and sends them to the swing angle synthesis computer through the computer serial port for swing angle synthesis processing; The capacitance value change The corresponding angle θ _x can be obtained, and the value of which capacitance changes, and then the direction of the pendulum rope can be judged; the same method can be used to obtain the angle θ _y in the other direction, and then the angles in the two directions can be combined to obtain pendulum angle value

Step 5: The work done by another set of spreaders is the same as above, and another set of swing angle values is obtained; the two sets of swing angle information are sent to the display screen of the cab for the driver's reference operation, and the swing angle information is sent to Synchronization/anti-sway control system to provide feedback information.

Compared with the prior art, the present invention has significant advantages:

The present invention is based on capacitance detection double-slinger bridge suspension swing angle measurement device, which utilizes the characteristic that the change of capacitance value is related to the facing area of capacitance. Angle value.

Next, the technical points are explained with accompanying drawings.

Description of drawings:

Figure 1 is a schematic diagram of the overall structure of a double-lift double-slinger bridge crane swing angle measurement device based on capacitance detection.

Fig. 2 is a structural diagram of the swing angle detection device of the swing angle measurement device for double-lift double-sling bridge cranes based on capacitance detection.

Fig. 3 is a partial view of the capacitive plate structure of the swing angle detection device of the swing angle measurement device of the bridge crane with double lifting and double spreaders based on capacitance detection.

Fig. 4 is a left view of the rotation of the capacitance plate of the swing angle measuring device of the swing angle detection device of the double hoist double spreader bridge crane based on capacitance detection.

Figure 5 is a schematic diagram of the composition of the x-axis and y-axis swing angle measurement device of the double-lift double-sling bridge crane swing angle measurement device based on capacitance detection.

Fig. 6 is a synthetic diagram of the bridge crane swing angle measurement device based on capacitance detection for double-lift double-spreader bridge crane.

Fig. 7 is a detection flow chart of the double-lift double-slinger bridge hanger swing angle measurement device based on capacitance detection.

Reference signs are as follows: 1-trolley mechanism; 2-driving mechanism of trolley; 3-cart, 4-driving mechanism of cart; 5-slinger hoisting motor; 7-first spreader of double spreader bridge, 8-the second spreader of the double spreader bridge; 9-swing angle synthesis computer; 10-bridge crane cockpit; 11-swing angle detection device; 12-sling of bridge crane; 13-signal processing device; 14- Conductor; 15-spreader lifting motor shaft; 16-light pendulum; 17-black box; 18-right capacitor negative plate; 19-capacitor positive plate; 20-left capacitor negative plate.

Detailed ways:

The preferred implementation examples of the present invention are given below in conjunction with the accompanying drawings to describe the technical solution of the present invention in detail.

In FIG. 1 , the trolley mechanism 1 is a mounting platform for the swing angle measuring device and the lifting motor. The hoisting motor 5 of the spreader is responsible for the lifting movement of the spreader and the load. The first spreader 7 of the double spreader bridge crane and the second spreader 8 of the double spreader bridge can work together and interlock, or they can work separately Work independently. The double-lift double-spreader bridge crane can simultaneously load and unload two 40-foot or four 20-foot containers.

In Fig. 2, when the suspension rope 12 swings, it will drive the light pendulum 16 to rotate and swing; the positive plate 19 of the capacitor plate is connected with the light pendulum 16, and rotates with the rotation of the light pendulum 16; The rotation of the positive plate 19 of the capacitance will cause the change of the facing area with the negative plate; the capacitance measurement circuit will be connected with the signal processing device 13 by the wire 14 and transmit the measurement data signal to the signal processing device 13, and the signal processing device 13 will signal After pre-amplification and A/D conversion, it is sent to the swing angle synthesis computer 9 for subsequent analysis and processing.

Fig. 3 is a partial view of the capacitive plate structure of the swing angle detection device of the swing angle measurement device of the bridge crane with double lifting and double spreaders based on capacitance detection. The capacitor positive plate 19 and the left capacitor negative plate 20 form a first capacitor, and the capacitor positive plate 19 and the right capacitor negative plate 18 form a second capacitor.

In Fig. 4, the swing of the lightweight pendulum 16 will drive the positive plate of the capacitor to rotate. At this time, the area can be changed according to the rotation, resulting in the change of the capacitance. Only the change value of the capacitance needs to be processed, and the signal processing device 13 can be used. The size and direction of the swing angle can be detected in real time.

Factors such as the operation of the cart or trolley and external wind disturbance will cause the load to swing, and at the same time, the lifting rope will swing with the load. The swing of the sling will drive the light pendulum 16 to swing, and then drive the capacitive positive plate 19 to rotate. Since the swing angle of the hanger generally does not exceed Therefore, the size of the capacitor plate only needs to be a semicircle to meet the requirements.

Assume that the swing angle of the first spreader 7 and the second spreader 8 is 0 when they are not working and have no disturbance, and the information measured at this time is the initial position information. When the trolley starts to move, it drives the sling to move, and the sling drives the movement of the lightweight pendulum 16, and then drives the rotation of the capacitor plate 19. Since the capacitance value is related to the area directly opposite, the change of the capacitance value obtained from Changes in size and rotation angle. The relationship between the change of the capacitance value and the angle is derived as follows:

Assuming that the effective coverage with the fixed plate is S, when the moving plate has an angular displacement θ.

C ₀ is the initial capacitance, ε ₀ is the permittivity of free space, _εr is the relative permittivity of the medium between the plates, and d is the distance between the two plates.

According to the above reasoning, it can be concluded that the capacitance variable ΔC and the angular displacement θ are in a linear relationship. Therefore, as long as the capacitance change is measured, the angular displacement, that is, the value of the rotation angle θ _x , can be obtained.

Similarly, the rotation angle θ _y in the y direction can be measured.

In Fig. 5, each group of spreader swing angle detection devices is composed of two sets of light weight pendulum frames, two sets of semicircular light weight swing frames are installed perpendicularly to each other along the x-axis and y-axis The swing frames are just tangent (the large lightweight swing frame surrounds the small lightweight swing frame), and there is a smooth slit in the middle of each swing frame, and the suspension rope 12 passes through the slits of the two swing frames successively. When 12 swings, it will drive the two lightweight swing frames 16 to rotate and swing together, and then transform and decompose the swing angle of the spreader and the load into the respective axial rotations of the x-axis and the y-axis.

Next, the working principle of the pendulum device group in the x-axis direction will be described in detail. When the sling 12 drives the rotation of the lightweight pendulum, it causes the positive plate of the capacitor to rotate, resulting in a change in the area facing the capacitor. When the sling swings in the direction of the positive x axis, the positive plate 19 of the capacitor and the negative plate 20 of the left capacitor will be caused. The facing area of the right capacitor changes, causing the capacitance value of the first capacitor to change, but the facing area of the right capacitor negative plate 18 and capacitor positive plate 19 does not change, so the capacitance value of the second capacitor does not change. The change in the capacitance of the negative plate 20 of the left capacitor will cause the change of the voltage value at both ends of the capacitor, and then the change information is sent to the signal processing device 13 and then sent to the swing angle synthesis computer to obtain the angle value of the direction and the swing direction. When the hanging rope swings towards the negative x-axis direction, the area of the right capacitor negative plate 18 and the positive capacitor plate 19 changes, causing the capacitance value of the second capacitor to change. The processing device 13 does not change the capacitance value of the second capacitor at this time. The same is true for the direction of the y-axis, and will not be repeated here.

In Fig. 6, θ _x and θ _y are the axial motion components of the pendulum angle obtained through measurement and calculation.

It can be obtained from the figure:

by the formula Calculate the pendulum angle value.

Figure 7 is a flow chart of the measurement of the swing angle of the bridge with double spreaders.

When the bridge crane with double spreaders is working, firstly, the driver’s cab 10 sends a work instruction signal, the trolley 1 moves, and when the first spreader 7 and the second spreader 8 of the bridge crane start to run, the suspension rope is caused to swing. When the suspension rope swings, It will drive the swing of the lightweight pendulum 16, which in turn will drive the positive plate 19 of the capacitor to rotate. Since the two negative plates 18 and 20 below are fixed, there will be a change in the area of the positive, which will lead to a change in the capacitance. The change value of this capacitance is transmitted to the signal processing device 13, 13 carries out pre-amplification, A/D conversion and other processing on the signal, and then transmits it into the swing angle synthesis computer 9 for synthesis calculation, and obtains the first spreader 7 and the second hanger 7 respectively. The respective swing angle values θ ₁ and θ ₂ of the spreader. The swing angle value of the spreader is transmitted to the bridge crane display in the cab 10 for reference by the bridge crane operator, and at the same time provided to the bridge crane anti-sway/synchronization controller as feedback information for bridge crane control.

The details of the above main components are as follows:

Signal processing device 13: is made up of components such as CPU, memory, signal processing circuit and I/O interface, and wherein CPU is connected with memory, signal processing circuit, and I/O interface circuit is connected with signal processing circuit, and signal processing circuit can simultaneously process from x, y two signals. It performs pre-amplification, shaping filtering and A/D conversion on the corresponding two signals of the x and y coordinate axes (as a group of signals) sent by the pendulum angle detection device 11, and then sends the converted digital signal to the pendulum. The angle synthesis computer 9 performs further analysis processing. In the patented invention, the signal processing device 13 can process two sets of signals simultaneously.

Swing angle synthesis computer 9: receives the digital signals transmitted from the respective signal processing devices 13 of the two spreaders, and performs corresponding processing and calculation on the signals according to the relationship between the variation of the capacitance value and the direct-facing area, and finally obtains swing angle information. The respective swing angle information of the two spreaders is connected to the swing angle synthesizing computer 9 by the signal processing device 13 through different serial communication interfaces, and 9 judges which hanger the calculated swing angle information comes from according to the serial port of the signal input signal. The obtained swing angle information is transmitted to the bridge crane display in the cab 10 to provide reference for the operation of the bridge crane driver, and can also be fed back to the bridge crane anti-sway/synchronization controller as control reference information.

The specific work of the bridge crane swing angle detection system involved in the present invention is as follows:

When the double spreader swing angle detection device 11 is installed, it is necessary to set the initial position information of each component as the initial reference position. The setting process is as follows: when the trolley has not moved, The two slings hang down naturally. At this time, the sling does not have any swing angle, and the light-weight pendulum 16 and the positive and negative plates of the capacitor do not rotate at all. At this time, the positive plate 19 of the capacitor is completely overlapped with the positively facing areas of the two negative plates. . The various information of the above-mentioned initial positions are recorded, and the signals obtained by the two sets of swing angle detection devices are used as initial references for calculation of the swing angle. The driver's cab 10 sends an operating command to the double-sling bridge crane, and the movement of the trolley drives the respective suspension ropes 12 to swing. The swing of the sling will simultaneously drive the light pendulum in the x-axis and y-axis directions to generate swings, and the swings in the x-axis and y-axis directions will be brought to the rotation of the positive plates of their respective capacitors to obtain the relative capacitance variable and signal The processing device 13 receives the two-way suspension rope swing signals sent by the respective swing angle detection devices 11 of the x-axis and the y-axis, and sends the signals to the swing angle synthesis computer 9 through the computer serial port for processing after amplification and A/D conversion. Calculating through 9 can detect the position and size of the swing angle in real time.

The work of the other group of spreaders is consistent with the above. After obtaining the information of the swing angle of this group, the spreader swing angle information of the two groups is sent to the display of the cab 10 for reference by the bridge crane driver, or sent as feedback information. into the anti-sway/synchronization control. In the actual working condition of the bridge crane with double lifts and double spreaders, the first spreader 7 and the second spreader can work independently of each other or can work interlocked and synchronously. In the independent working mode, the two spreaders do not affect each other, and two angle values are obtained respectively; in the interlocking working mode, the swing angle values of the two spreaders calculated and processed by 9 should be the same in theory, if they are different, they can be The similarity and difference signals are then processed correspondingly by the swing angle synthesis computer 9, so that the two swing angle values are compared with each other and corrected to ensure a better synchronization effect.

The swing angle detection of double slings detects the information of the two slings on the basis of the above. Each sling needs two sets of the same structure, and each set of structures includes (a rotatable positive plate, two negative plates, capacitance measurement circuit ) is used to detect the direction and magnitude of an angle in one of the directions. Then the situation of double spreader needs four sets of such structures, and the invention of this patent can detect three spreaders by analogy, and even the swing angle problem of many spreaders.

Claims (2)

1. A double-slinger bridge hanger swing angle measuring device based on capacitance detection, which is arranged on a trolley, the trolley mechanism is arranged on a cart mechanism, and a bridge crane cab is provided on the cart mechanism, and the trolley The mechanism is provided with a pair of lifting motors, and each lifting motor includes a rotating shaft, and the rotating shaft of each lifting motor is connected to a sling through a sling. It is characterized in that the swing angle measuring device includes: a pair of signal processing devices, Swing angle synthesis computer, a pair of swing angle detection devices; the signal processing device is symmetrically arranged on the top of the trolley mechanism, and the signal processing device includes a voltage amplifier, a rectifier filter, an A/D converter, and the input terminal of the voltage amplifier It is connected with the output terminal of the capacitance measurement circuit, and the output terminal of the voltage amplifier is connected with the rectification filter and the A/D converter in turn, and then output to the swing angle synthesis computer; the swing angle synthesis computer is arranged on the top of the trolley mechanism, located A pair of signal processing devices are respectively connected with a pair of signal processing devices; a pair of swing angle detection devices are symmetrically arranged at the bottom of the trolley, each of the swing angle detection devices is connected with a corresponding signal processing device, and each suspension rope Pass through the corresponding swing angle measurement device and connect with the corresponding spreader; one is used to display the swing angle information display module, which is installed in the cab of the bridge crane and connected with the swing angle synthesis computer; the swing angle detection device includes two Lightweight pendulum and black box; two lightweight pendulums are installed perpendicular to each other along the x-axis and y-axis respectively, and two semicircular light-weight pendulums are tangent; each light-weight pendulum is arranged along the circumferential direction There are smooth slits, and the slings pass through the slits of the two lightweight pendulums successively; there is a capacitance measurement circuit inside the black box, the positive plate of the capacitor on the side of the half cylinder, the negative plate of the capacitor on the side of two quarter cylinders, Two negative plates are set opposite to the positive plate of the capacitor; the positive plate of the capacitor and the negative plate of the left capacitor form the first capacitor; the positive plate of the capacitor and the negative plate of the right capacitor form the second capacitor; the two negative plates are fixed on the bottom of the black box, and the positive electrode of the capacitor The board is connected with the light pendulum and swings accordingly; the output terminal of the capacitance measuring circuit is electrically connected with the corresponding signal processing device. 2. A double-slinger bridge hanger swing angle measuring device based on capacitance detection, using the double-slinger bridge hanger swing angle measurer based on capacitance detection as claimed in claim 1, is characterized in that comprising the following steps: Step 1: Set the initial position of each component, and use this as the initial reference position. The setting process is as follows: first let the two spreaders of the double-sling bridge crane hang down naturally, and at this time the suspension rope has no swing angle. The lightweight swing frame and the positive plate of the capacitor plate do not rotate; the signals obtained by the two sets of swing angle detection devices are used as the initial reference value for the calculation of the swing angle. At this time, the capacitance value received by the signal processing device indicates that the swing in the current axial direction angle is 0; Step 2: The driver's cab sends out the operation instructions of the bridge crane, and the bridge crane controls the operation of the corresponding spreader according to different operation commands, and the hanging ropes connected to each spreader swing; Step 3: The swing of the sling will drive the rotation of the lightweight pendulum to cause the rotation of the positive plate of the capacitor, causing the change in the facing area between the negative plate and the positive plate of the capacitor, and the change of the value of the first capacitor or the second capacitor. The obtained signal is transmitted to the signal processing device; Step 4: The signal processing device receives the signals from the x and y directions for processing, amplifies, filters, A/D converts and sends them to the swing angle synthesis computer through the computer serial port for swing angle synthesis processing. The same method obtains another The angle in the direction, and then combine the angles in the two directions to get the swing angle value of the pendulum rope Step 5: The work done by another set of spreaders is the same as above, and another set of swing angle values is obtained; the two sets of swing angle information are sent to the display screen of the cab for the driver's reference operation, and the swing angle information is sent to Synchronization/anti-sway control system to provide feedback information.