JP2000226184A - Signal transmitting method accompanying automation of crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively perform automation of a crane in a short period by constituting a signal on a crane to a ground side by wireless after the signal is converted into serial data in accordance with an automation remodeling performing an operation of an existing remote manual operation type overhead traveling crane by an instruction of a host computer. SOLUTION: In a crane 3 installed so as to travel along a pit 1, a crab 4 is disposed and a winding drum 41, a decelerator 42 and a motor 43 are arranged. When the crane 3 is automated, signals of various kinds of additional sensors of a load cell for detecting load and signals of an existing limit switch are aggregated, this mixed aggregated signal is transmitted to a receiver 13 installed on a driver's cab 6 on a ground side by signal transmitting devices 11, 12 mounted on the crab 4 and the crane 3 by wireless and is transmitted to a crane control device 8 of an electric room 5 from this receiver 13 by wire. Reserved space for additional wiring and a noise measure are not required, automation can be easily performed and a highly accurate driving operation as an automatic crane can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for transmitting a signal accompanying the automatic remodeling of a crane, and more particularly to a method for easily controlling an existing remote manually operated overhead traveling crane installed in a cleaning plant or the like so as to be compatible with automatic operation. The present invention relates to a signal transmission method accompanying an automatic remodeling of a crane that can be remodeled.

[0002]

2. Description of the Related Art Conventionally, when retrofitting an existing remote manually operated overhead traveling crane installed in a waste cleaning plant so that it can be automatically operated, an encoder for measuring the position of the crane and an operating range are specified. In order to transmit these signals from the club to the girder, or from the girder to the ground operator side, add various sensors such as various limit switches, load cells for load measurement, etc.
Multiple cabtire cables were added and installed as curtain cables.

[0003]

As described above, in order to modify a conventional remote manually operated crane so that it can be automatically operated, a cable for transmitting signals from various sensors and the like to a control panel on the ground is provided. When adding cables, whether the existing cable is a curtain cable system or a cable carrier system, there is usually no spare space for additional wiring, so it is necessary to rebuild the entire carrier for additional wiring. Yes, remodeling costs are high. Since signal lines having different signal levels and signal bands pass in the vicinity of the power line for driving the motor, noise due to the induced current is likely to enter the signal line, and the cost of remodeling for measures against this noise increases. The cabtire cable has a finite flex life, requires periodic replacement, and increases maintenance costs. Normally, multiple cranes in a garbage plant are installed in the garbage plant, so remodeling work on the crane can be performed relatively easily. There are many restrictions such as the construction period, and it cannot be easily remodeled. And so on.

The present invention has been made in view of the above-mentioned problems of the conventional method for automatically remodeling a crane, and has as its object to provide a signal transmission method accompanying the automated remodeling of a crane, which can be automated and remodeled in a short period of time and at low cost. I do.

[0005]

In order to achieve the above object, a signal transmission method according to the automated remodeling of a crane according to the present invention is directed to an automated method for operating an existing remote manually operated overhead traveling crane according to an instruction of a host computer. According to the modification, the signal on the crane is converted to serial data and then transmitted wirelessly to the ground.

In the signal transmission method accompanying the automatic remodeling of the crane, the signal on the crane is transmitted to the ground side by radio, so that the existing remote manually operated overhead traveling crane requires additional wiring. There is no need for extra space or noise countermeasures, it can be easily remodeled, and can be operated with high precision as an automatic crane.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a signal transmission method according to the automatic remodeling of a crane according to the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic plan view of a cleaning plant, showing an example of a configuration in which a crane 3 is installed so as to run along a pit 1. The garbage collected from each household by the garbage truck and carried into the waste cleaning plant is first put into the pit 1 and temporarily stored, and then re-transferred to another place in the pit by the crane 3. In addition, the garbage is homogenized, and the garbage after reloading by the crane 3 is put into the hopper 2 of the incinerator.

The crane 3 is provided with a club 4 which can be traversed. On the club 4, a hoist drum 41, a hoist reducer 42, a hoist motor 43, a hoist upper limit switch (not shown), a traverse motor (Not shown), a traverse speed reducer (not shown), a traverse limit switch (not shown), and the like are arranged, and a grab bucket that grasps dust by a wire rope W wound on a hoist drum 41 can be opened and closed. To support it.

The power supply to the hoisting motor 43 and the traversing motor and the signals from the limit switch and the like are carried out by supporting the cabtire cable on a curtain rail or a tension wire with a hanging bracket, and moving the cable in accordance with the movement of the club 4. It is laid as a curtain cable 9 to be expanded and contracted. Similarly, the curtain cable 10 is laid along the traveling rail R between the crane 3 and the ground.

The curtain cables 9 and 10 are connected to a crane control device 8 in an electric room 5 provided on the ground. The crane 3 is operated using an operating device 7 such as a joystick or a notch type commander provided in the operating cab 6 so as to be remotely controlled from the cab 6 facing the pit. Can be Although the electric room 5 is a room independent of the cab 6 in the embodiment shown in FIG. 1, the electric room 5 may be used also as the cab 6.

Next, a signal transmission method according to the automatic remodeling of the crane of the present invention will be described. When the crane 3 is automated, an encoder for detecting the position of the hoist on the club, a load cell for detecting the load applied to the hoist drum, a signal amplifier for the load cell, and an ID for detecting the traverse position are provided.
A sensor, a device for detecting a turbulent winding of a hoisting wire rope, and the like are added, and a fall detection sensor is added to the grab bucket, and an ID sensor and the like for detecting a traveling position are provided on the girder or the saddle. ). In order to transmit these signals and the signals of the limit switches such as the existing hoisting upper limit, traverse limit, traveling limit, etc. from the crane 3 to the ground side, the signals are once aggregated on the club and the girder,
This mixed and aggregated signal is wirelessly transmitted to signal receiving devices 13 and 12 mounted on the club 1 and the crane 3 to the receiving device 13 installed in the cab on the ground side, and the receiving device 13 sends the signal to the crane control device 8 by wire. Try to transmit. In this case, since a wiring duct or the like is generally provided between the operation room 6 and the electric room 5 of the crane, it is possible to easily add signal lines.

FIG. 2 shows the configuration of the signal transmission device 12 and the reception device 13. Signals of a plurality of load measurement load cells installed on the crane side do not require individual load values but require an overall added value. Therefore, the signals from each load cell are aggregated by an addition circuit 101, and a low-pass filter 102 The band is limited, and the A / D converter 104 converts the analog signal into numerical data.

The encoder for detecting the winding position has 9 encoders.
Interface circuit 10
The signal is matched by 3 and converted into numerical data by the counter 105. The counter value is reset by a signal of a hoisting limit switch indicating a known position such as an upper limit of hoisting or a hopper input position.

The traversing position is detected without contacting the traversing rail.
Using an ID reader (transponder reader) for reading information written on the D tag (transponder), the ID tag is laid along the traversing rail. When the club passes over the ID tag, the tag information is read out without contact. Normally, information of an ID tag can be transmitted in the order of several tens of bytes. However, one byte of data is sufficient because the horizontal position corresponds only to the data where the tag is laid.
The parallel signal obtained by expanding the byte data into a bit pattern is subjected to noise removal or the like by the signal matching circuit 106 and matched.
The data is input by the input gate circuit 107 and converted into numerical data. Traverse limit switch signal, turbulence detection signal,
Similarly, the bucket falling signal is also applied to the signal matching circuits 108 and 11.
0, 112, the input gate circuits 109, 11
At 1,113, the data is converted into numerical data.

Similarly, the signal of the winding limit switch is matched by the signal matching circuit 114, and is converted into numerical data by the input gate circuit 115.

Since each signal has a different band required for automatic operation and a different time delay of the signal, there is no need to transmit all the signals in the same cycle. For the band of the load signal, a band of about 5 Hz is sufficient for the purpose of detecting the landing of the grab bucket on the dust and measuring the load value of the grabbed dust. For the signal from the hoist encoder, the two-phase signal generated by the encoder has already been counted by the counter, so the crane control may have a position detection resolution of about 50 mm, and the transmission cycle determined from the moving speed at the maximum unwind speed. Is about 70 ms. The delay of the signal of the ID sensor for detecting the traversing position and the traveling position is set to 50 times in consideration of the ID reading time 70 to 80 ms.
ms. The limit switch delay needs to be processed at the highest speed in crane control, and the transmission delay is about 20 ms. These signals do not always need to be transmitted periodically, but are transmitted only when the state or the count value has changed.

In transmission, as shown in FIG. 3, there is an idle time for a transmission frame 300 that is effective in terms of time.

FIG. 4 shows the details of the transmission frame. The frame includes a frame identification unit 301, a valid data unit 302,
It comprises an invalid data section 303 and a frame check section 304. The types of frames to be transmitted are six types of frames: load data (two types), encoder count value, position detection ID, limit signal, and all data. The frame identification 301 only needs to identify six types of frames, and has a fixed length of 3 bits. The invalid data section 303 inserts an invalid bit string such that the sum of the number of bits of the frame identification section 301 and the valid data section 302 and the sum of all the bits of the invalid data section 303 become an integral multiple of 7 or 8. This is because the start-stop synchronous serial data transmission is performed with 7 or 8 bits as a basic unit. The frame check unit 304 includes a cyclic code unit 304a and a checksum unit 304b. The cyclic code unit 304a stores a code that repeats synchronously in order to check for a loss of the entire communication data frame.
For example, an integer value that can be represented by 1 byte of 0 to 255 is set to 1 every time a frame is transmitted from the transmitting side.
Make sure to send them in increments. The receiving side checks the continuity of the cyclic code, and if discontinuity occurs, it can detect that a frame has been lost, and outputs a signal transmission error signal. The checksum unit 304b sends the lower byte of the sum of the data in the frame. The receiving side compares the lower 1 byte data of the total sum of the data up to 301, 302, 303 and 304a of the frame with the content of 304b, and can detect that the frame is damaged during the transmission due to the mismatch. Outputs a transmission error signal. Also,
If the receiving side stops receiving frames for a certain period of time,
It regards the failure on the transmission side or the reception side and outputs a signal transmission error signal.

The load value can be reduced by transmitting the load value standardized by the rated load of the crane, and the data amount can be reduced.
The data is 8-bit data, and it is possible to detect landing of the grab bucket, grasping, or insufficient grasping load. The load value is transmitted as 16-bit data when 8-bit data is insufficient in accuracy when the result of managing the input amount to the hopper is performed. Therefore, two types of frame identification are provided for the load value.

As the count value of the encoder, a value standardized by the lift of the crane may be transmitted, and can be controlled by 10-bit data.

The limit switch has the number of bits corresponding to the number of the signals.

Transmission connects to the wireless unit 118 via the serial data interface 117. The wireless unit 118 transmits and receives wireless data via the antenna 119. A series of processing is performed by software of the arithmetic processing unit 116 including a CPU, a RAM, a ROM, and the like.

The radio is less susceptible to inverter noise and the like in the operating environment of the crane, and is capable of high-speed signal transmission.
A radio system in the 2.4 GHz band, that is, a radio system in which the frequency spectrum of a signal is spread over a wide area using a high-speed pseudo-noise code, transmitted, and demodulated on the receiving side without data error is preferable. is there. The receiving unit 13 receives a signal with the wireless unit 202 and the antenna 201 and sends the signal via the serial interface 203 to the CPU, RAM, R
The signal is reconstructed from the frame received by the processing device 204 constituted by the OM. Load register signal is output to register 205
And output as parallel numerical data via the output interface 206. The method of converting to an analog signal by D / A conversion requires an analog input in the crane control device, noise measures in the transmission process to the crane control device are required more than digital transmission, resulting in a cost increase. It is not suitable for automated remodeling of cranes because it leads.

Similarly, the winding encoder signal holds the count value in the output register 207 and outputs it via the output interface 208. The ID signal for position detection is held in the output register 209 and output to the output interface 21.
Output via 0. The transverse limit switch is held in the output register 211 and output via the output interface 212. The turbulence detection signal is held in the output register 213 and output through the output interface 214. The bucket falling signal is held in the output register 215 and output via the output interface 216. The winding limit switch is held in the output register 217 and output via the output interface 218. The signal transmission error signal is held in the output register 219 and output via the output interface 220. The traveling signal transmission device arranged on the girder or the saddle includes only the traveling position detection ID sensor signal and the traveling limit switch.

The hardware of the device can be common to the signal transmission device 12 of the club. If the unused analog signals are short-circuited and the other signals are short-circuited or opened, the signal state does not change. Since no signal transmission is performed, processing can be performed with the same software. In order to reduce the cost of hardware, it is possible to use another device in which unnecessary parts are deleted.

As described above, the crane control device in which the signal necessary for the automatic operation is wirelessly provided on the ground from the crane without laying a new curtain cable on the power line of the motor and the signal line used in the manual operation. Can be transmitted.

Although the present embodiment has been described with respect to a crane in a cleaning plant, the present invention is applied to signal transmission between a club and a girder of an overhead traveling crane having a crane control device mounted on a girder used in steel or general factories. In addition, automated remodeling can be performed at low cost and in a short time. The number of analog signals, the number of encoders, and the number of various limit switches and sensors vary depending on the target crane, and the use of a signal transmission device suitable for the target crane makes it easy to automatically remodel a manually operated crane. It can be carried out.

[0029]

According to the signal transmission method according to the automatic remodeling of the crane of the present invention, the signal on the crane is transmitted to the ground side by radio, so that the existing remote manually operated overhead traveling crane is used. In addition, there is no need for extra space for additional wiring or noise countermeasures, and it can be easily and inexpensively remodeled, and high-precision operation can be performed as an automatic crane.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing an embodiment of a signal transmission method according to the automatic remodeling of a crane of the present invention applied to a crane in a cleaning plant.

FIG. 2 is a configuration diagram of a signal transmission device and a reception device.

FIG. 3 is an explanatory diagram of a transmission signal.

FIG. 4 is an explanatory diagram of a transmission frame.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pit 2 Incinerator hopper 3 Crane 4 Club 5 Electric room 6 Operation room 7 Operating device 8 Crane control device 9 Curtain cable 10 Curtain cable

Claims (1)

[Claims] 1. With the automatic remodeling to operate an existing remote manually operated overhead traveling crane according to an instruction of a host computer, a signal on the crane is converted into serial data and then transmitted to the ground side by radio. A signal transmission method according to the automated remodeling of a crane, characterized in that: