RU2246441C2 - Method of and device for automatic coordinate protection of tower crane operating in confined spaces - Google Patents

Abstract

FIELD: materials handling facilities; tower cranes.

SUBSTANCE: according to production plan, zones with different types of crane movement limits related to concrete objects are defined. Said zones are introduced into personal computer, not included into instrument complex of coordinate protection, under laboratory conditions. Using special software, array of data is formed in computer, each element of which corresponds to building site member and contains information of prohibited movement of crane in corresponding point. Said array is recorded in reprogrammable read-only memory of coordinate protection system which, basing on signals from transmitters, defining position of crane and its members and by signals from reprogrammable read-only memory forms drive locking signals if crane or its working members get into restricted zone.

EFFECT: provision of crane coordinate protection of high efficiency using simple devices.

3 cl, 1 dwg

Description

1 Field of the invention.

The invention relates to crane safety devices, namely, to limit the movement of tower cranes when working in cramped conditions created by stationary objects.

2 Prior art.

Known methods and devices for restricting crane movements, including preliminary setting of permitted zones using cams and limit switches, which are used to block the movement of cranes and its elements (“Device for programmed control of the mechanism of rotation and departure of the boom.” AS USSR No. 464099, B 66 C 13/48, 1966).

The disadvantage of these methods and devices are significant restrictions on setting restriction zones, the complexity of the changeover when changing the position of obstacles, and the need to use cable connections placed on a crane platform.

The invention is known “Indicator of the position of obstacles for a jib crane" (AS USSR No. 1104095, B 66 C 23/88, 1984), which provides increased safety of the crane in cramped conditions by indicating obstacles on the display. The device contains sensors of the angle of inclination, rotation of the boom, the height of the load, the angle sensor of the boom, as well as signal converters and a display.

The disadvantage of this device is the lack of automatic control of the crane mechanisms and the need for the crane operator to simultaneously monitor the display and the actual position of the load on the crane hook.

Known coordinate protection systems, for example, the company Liebherr (according to the catalogs of the company), and given in the application of the Russian Federation No. 2093452, B 66 C 13/18, 15/00, 23/88, 1997, which use microcomputers installed directly on a crane. The contour of the zones where work is prohibited is entered into the memory of the microcomputer using the keyboard, and the microcomputer, using sensors to determine the position of the crane elements, generates blocking signals for its mechanisms to prevent the boom or load from entering the forbidden zones.

These systems, which are closest to the one proposed, require the use of sophisticated equipment with a display and an input device that can withstand severe climatic and mechanical operating conditions, as well as highly professional personnel to enter parameters for restricting crane movements and servicing equipment, which leads to the limited use of such systems on most tower cranes.

3 The invention.

The technical problem is to build a system of automatic coordinate protection of the crane in cramped conditions, taking into account the position of the crane elements relative to objects located on the construction site, without the use of complex electronic devices and branched cable connections.

The present invention solves the problem of creating an automatic coordinate protection system for tower cranes operating in cramped conditions.

Distinctive features of the proposed coordinate protection system are:

- separation of restriction zones by type of restriction;

- assignment of restriction zones in accordance with the work plan;

- separation of tasks for entering restriction zones and calculations for the formation of signs of restriction and tasks for determining the location of a crane at a construction site, making decisions and issuing control signals for crane drives.

In the proposed system, the following types of restriction zones are adopted when the crane is operating in cramped conditions:

- zone without restrictions;

- a zone with a restriction on any element of the boom;

- area with a restriction on the departure of the goods;

- zones with a restriction on the height of the load;

- restricted area for any element of the boom;

- restricted area for restrictions on the departure of the goods;

- hazardous area in which an audible signal is issued.

The types of restriction zones in accordance with the requirements of regulatory documents on the safety of construction work are determined by objects located on a construction site in the zone of reaching the working bodies of the crane. Differentiation of zones of restriction by type allows optimizing the operation of the crane in compliance with the required standards. The configuration and location of the restriction zones correspond to the configuration and location of objects at the construction site.

Forbidden zones are formed around restriction zones (objects), their width is set taking into account the requirements of regulatory documents (overall dimensions of lifted loads, lifting height, etc.).

The restriction zones, forbidden and dangerous zones are set on a PC such as IBM PC, into which specialized software is loaded. For a given crane track length and maximum reach (boom length), a construction site is drawn on the PC monitor screen, divided into discrete elements, the size and quantity of which is determined by the accuracy of the measurements of the corresponding parameters. Using the mouse and keyboard, each element of the construction site is assigned the type of zone (in different colors on the PC monitor) in accordance with the presented work plan. After setting all the zones on the PC, a calculation is performed, as a result of which a numerical array is formed, each element of which is associated with an element of the construction site and is an eight-bit binary number, each bit of which is intended to control the corresponding crane mechanism.

The generated data array is written to the reprogrammable read-only memory (EPROM) of the construction site parameters block, which is installed in the control unit of the coordinate protection system.

In the control unit located in the crane cabin, the spatial position of the crane and its working bodies at the construction site is determined by signals from the sensors of the crane position on the crane path, the azimuthal position of the boom, the reach and the height of the load. Based on the totality of these parameters, the corresponding array element is read from the EPROM, which contains information about the allowed and prohibited movements of the crane and its organs.

Separation of the functions of inputting information and preliminary calculation on a PC makes it possible to dramatically simplify the equipment installed on the crane, since there is no need for a complex and unreliable input device (keyboard), a complex solver and a universal device for displaying information. In addition, the requirements for the qualifications of workers servicing equipment on the crane are reduced.

The drawing shows a structural diagram of a coordinate protection system for a tower crane.

The system contains analog sensors for the position of the crane on the crane path 1, the azimuthal position of the boom 2, the departure of the load 3 and the height of the load 4. The signals of the sensors 1-3 are switched by an analog multiplexer 5 to the input of an analog-to-digital converter (ADC) 7, which converts the analog signals of the sensors into binary code. From the ADC output, a digital code is supplied to the inputs of the registers 9, 10, while in the register 9 the code of the position of the crane on the crane path is recorded, and in the register 10 is the code of the angular position of the crane's jib. The combination of these parameters uniquely determines the spatial position of the crane and its boom at the construction site and is used as address signals for the EPROM 11, which stores information about the signals for controlling the crane drives, as well as warning signals about the crane entering the danger zone. This information from the EPROM 11 is copied to the output register 13. In addition, the EPROM 11 contains information on the allowable departure of the cargo for all possible crane positions on the crane platform, which is compared with the current departure value in the comparison scheme 12. If the current departure of the cargo is more than the permissible, then in the corresponding category of the output register 13 is recorded the signal blocking the operation of the drive departure. The signals from the output register are supplied to the crane drive control unit 14. If the end of the crane boom or load falls into the danger zone, the system generates a general warning signal for the crane operator, and in cases where the crane boom or cargo falls into the forbidden zone, blocking signals of the crane drives are generated. At the same time, the system does not prohibit turning on the drives, allowing to remove the crane from the forbidden zone.

The channel for processing the height of the load lifting provides the operational setting of the required value of the height in the zone of its restriction. This is achieved by the fact that, in accordance with the values of the departure of the cargo and the azimuthal position of the boom, the control code of the analog switch 6 is selected from the EPROM, which corresponds to the number of the height limit zone. This control code connects one of the resistors to the analog comparator 8, with the help of which the height level h1-h3 is set. The second input of the comparator receives a signal from the output of the load height sensor 4. If the height of the load exceeds a predetermined level (h1-h3), a control signal is generated at the output of the comparator 8, which is recorded in the output register 13 and then transmitted to the crane drive control unit 14.

4 List of figures of drawings and other materials.

The drawing shows a structural diagram of the coordinate protection system of a tower crane, where (1) is the crane position sensor on the crane path, (2) is the boom azimuth sensor, (3) is the departure sensor, (4) is the load height sensor, ( 6) - input device for the level of permissible height of the cargo position (h1, h2, h3), (5) - analog multiplexer, (7) - analog-to-digital converter, (9) - crane position register on the crane runway, (10) - register the angular position of the crane jib, (11) - EPROM of the block of parameters of the construction site, (12) - the circuit is compared ia, (6) - analog switch for setting the height level, (8) - analog comparator, (13) - output register, (14) - crane drive control unit.

5 Information confirming the possibility of carrying out the invention.

The device in accordance with the above description can be implemented using digital microcircuits of both small and medium degree of integration, and large, in particular microcontrollers. As an EPROM, you can use flash memory or RAM chips that store information when the power is turned off and have the volume necessary to solve the problem.

As sensors of the position of the crane and its working bodies can be used resistive (or other type) sensors, widely used at present, for example, in the limiters of the lifting capacity of cranes.

Special software can be developed using one of the widely used programming systems.

The automatic coordinate protection system was implemented and tested under operating conditions on tower cranes of the KBM-401P and KB-473 type. The control unit was made on chips of the K561, KR1554 series, and flash memory chips of the type AD29С010А (128К × 8) were used as EPROM chips. Tests have shown that the system is fully operational in accordance with the requirements. Information was entered into the PC in accordance with the description for specialized software, and this work can be performed by a specialist with a secondary technical education familiar with working on a PC.

Claims (2)

1. A method of automatic coordinate protection of a tower crane operating in cramped conditions, in which sensors are located on crane mechanisms to determine the position of the crane and its elements, characterized in that zones with different types of restrictions on the movement of the crane and its elements are assigned, and functions for entering information about these zones and calculations for the formation of signs of blocking of crane drives and functions for determining the location of the crane and its elements at the construction site and issuing signals drive controls to prevent dangerous movements of the crane are performed separately, while entering information about the location of objects on the construction site in accordance with the work plan is performed using a personal computer that is not included in the instrument complex of the tower crane coordinate protection system and is equipped with appropriate software using a personal computer in accordance with the zones of restrictions of different types, having a configuration and location corresponding to the configuration and location of objects on the construction site dash and subdivided into a zone without restrictions, a zone with a restriction on any element of the boom, a zone with a restriction on the height of the load, a zone with a restriction on the height of the load, a prohibited zone of restriction on any element of the boom, a prohibited zone of restriction on the departure of the cargo, a dangerous zone with the issuance warning sound signal, calculate and form a numerical array with elements mapped to elements of the construction site and representing eight-bit binary numbers in which each bit is designed to control using the appropriate mechanism of the crane, after which the resulting array of numbers is written into the reprogrammable memory (EPROM) of the block of parameters of the construction site, which is installed in the control unit of the coordinate protection system, which, according to the signals from the sensors of the crane position on the crane path, azimuthal position of the boom, reach and lift height load determine the spatial position of the crane and its working bodies and the combination of these parameters form the control signals of the crane drives. 2. The system of automatic coordinate protection of a tower crane operating in cramped conditions, comprising a set of position sensors of the crane and its working bodies and a control unit for generating control signals for the crane drives, characterized in that the sensors of the position of the crane on the crane runway are introduced into it, azimuthal position of the boom, departure and lifting heights of the load, device for entering levels of permissible height, position sensors of the crane on the crane runway, azimuthal position of the boom, departure for dix, analog load a multiplexer for alternately reading sensor signals, an analog-to-digital converter for converting analog sensor signals to a digital binary code, crane position registers on the crane path and the crane boom angular position to uniquely determine the position of the crane and its boom at the construction site, EPROM of the construction site parameters block for storage of crane drive control signals, output register, scheme for comparing the current value of the departure of the cargo with a permissible value read from the EPROM, an an analogue switch for setting elevation levels, an analog comparator for generating a signal that the load exceeds the permissible height and a crane actuator control unit that provides the position of the crane and its boom on the crane platform, the height of the load and the reading of these parameters from the EPROM about the permitted movements used to block crane drives and ensuring its safe operation.