RU2391285C1 - Jib crane load limiter - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: invention relates to jib crane load limiter incorporated with crane control and protection systems on cranes with detachable or movable counterweight. Said limiter comprises transducers mounted on the carne to measure load describing parametres, spatial position of crane jib and/or grippe and spatial position of counterweight. Said limiter comprises actuator and digital computer connected thereto. Said computer allows receipt and processing transducer output signals and determining crane current load, comparing current load and maximum tolerable load loaded into limiter memory device, and generating preventive signal and/or transmitting to crane motion interlocking signal to actuator to prevent crane overload. Said limiter comprises transducer of counterweight spatial position representing a transducer of availability and/or spatial position of several weights of detachable or movable counterweight on counterweight cantilever or on crane rotary platform. Limiter digital computer allows receipt and processing transducer output signals and determining crane current load, comparing current load and maximum tolerable load loaded into limiter memory device, and generating preventive signal and/or transmitting to crane motion interlocking signal to actuator to prevent crane overload.

EFFECT: higher safety and reliability of crane operation.

14 cl, 1 dwg

Description

The invention relates to hoisting-and-transport mechanical engineering and can be used in control systems and overload protection of hoisting cranes with removable or mobile counterweights, including pipe-laying cranes with reclining counterweights.

Known load limiter of a crane containing a digital computer, the information inputs of which are connected to the crane parameters sensors, including load sensors, the tilt angles of the fixed part of the crane and the position of the counterweight with a variable reach, the computer being configured to change the maximum allowable values of the longitudinal and transverse angles tilt of the crane depending on the position of the counterweight [1].

The disadvantage of this technical solution is the insufficiently complete consideration of the influence of the position of the counterweight on the safety of the crane, since this position is taken into account only when determining the maximum values of the longitudinal and transverse inclination of the crane when it moves without load.

The load limiter of a jib crane is also known, which contains a digital computer, the sensors of the crane parameters are connected to its inputs, including load sensors and counterweight masses, and the outputs are equipped with a visual display unit, an audible alarm unit and an actuator, and the digital computer is adapted to change the program their work in accordance with the measured mass of the counterweight [2].

The disadvantage of this limiter is the increased complexity of its implementation, since the design of the counterweight of the counterweight mass is much more complicated than the sensor of its spatial position and requires intervention in the power structures of the counterweight on the crane.

Closest to the proposed one is a load limiter of a crane with a graphic display, comprising an actuator and a digital computer connected to it, to the information inputs of which are connected load sensors and the spatial position of the boom and counterweight of the crane. In this limiter, the digital calculator provides information on the crane working area on the display screen from the condition of preventing the crane from overloading and collisions with obstacles taking into account the position of the counterweight, as well as transmitting to the actuator signals blocking crane movements when implementing its protection against overload taking into account the position of the counterweight [3].

The disadvantage of this limiter is the low functionality when implementing crane protection, due to the lack of control and indication of the positions of individual loads of the stacked counterweight, the lack of functions to control the position of the counterweight, etc.

The technical result to which the invention is directed is to increase the safety of the jib crane and its efficiency by expanding the functionality of the load limiter, including by:

- implementation of the control of the spatial position of not only the set-up counterweight as a whole, but also its individual cargoes, as well as taking into account the weight and position of each cargo in the program of work of the digital computer

- the formation of an additional warning signal for the crane operator about a decrease in the cargo stability of the crane due to the absence of any counterweight cargo or its inappropriate spatial position on the counterweight console or on the turntable of the crane;

- forming recommendations to the crane operator about the need or feasibility of changing the spatial position of the load or counterweight;

- generation of signals for automatic control of the drive for moving cargo or counterweight cargo from the condition of ensuring the safety of the crane;

- the formation of a signal to limit the transport speed of the crane in case the mobile or additional removable counterweight is not transferred to the transport position.

In the load limiter of the jib crane, containing sensors mounted on the crane and configured to measure parameters characterizing the load, the spatial position of its boom and / or load-bearing body and the spatial position of the counterweight, an actuator and a digital computer connected to it, configured to receive and processing the output signals of the sensors and determining the current value of the crane load, comparing the current value of the load with the maximum allowable load, p pre-recorded in its storage device, as well as with the possibility of generating a warning signal and / or transmitting to the actuator a signal blocking the movements of the crane aimed at preventing its overload, these technical results are achieved due to the fact that the spatial position sensor of the counterweight is made in the form of a presence sensor and / or the spatial position of one or more loads of a removable or movable counterweight on the counterweight console or on the turntable th tap platform, and digital computer is further configured to implement one or more functions:

- the formation of an additional warning signal about the absence and / or spatial position of the load or cargo counterweight, reducing the cargo stability of the crane;

- forming recommendations to the crane operator about the need or feasibility of changing the spatial position of the load or counterweight;

- generation of signals for automatic control of the drive for moving cargo or counterweight cargo from the condition of ensuring the safety of the crane.

To achieve these technical results, the limiter can be equipped with at least one discrete light, sound, symbolic and / or graphic indicator or display connected to or included in a digital computer.

In addition, to achieve these results, in various embodiments of the proposed technical solution:

- the digital computer is configured to automatically control the counterweight drive depending on the current value of the mass of the load on the load-gripping body (hook) or load moment, or upon detection of an operator’s command to put the crane into a state of lower cargo stability, for example, a command to lower the boom or turn the crane into side of less stability, or from the condition of simultaneously achieving own and / or cargo stability of the crane against tipping and preventing collisions of the counterweight with obstacle in accordance with the parameters or the coordinates of the obstacles previously stored in digital computer memory;

- the limiter is additionally equipped with a sensor for speed and / or direction of the wind, and the digital computer is configured to take into account the output signals of this sensor when generating an alarm signal, and / or when transmitting to the actuator a signal for blocking crane movements or moving the counterweight, and / or when transmitting to an actuator of the signal for automatic control of the counterbalance displacement drive from the condition of increasing the crane stability;

- the values of the mass of the load or each load of the counterweight are previously recorded in the memory of the digital computer and taken into account in the program of its work;

- the sensor of the presence or spatial position of each counterweight cargo is made using non-contact identification technology in the form of a transponder attached to the cargo or an identifier and a device for reading information from it, and the transponder or cargo identifier is made, in particular, with the ability to store and transmit information about the mass of this cargo and / or its installation location, and the information reading device is configured to transmit this information to a digital computer, which is adapted to changing the program of work in accordance with the received information;

- the sensor of the presence or spatial position of one or more counterweight loads is made in the form of a non-contact ultrasonic, or capacitive, or inductive, or optical, or radar range finder without a reflector, with a passive signal reflector or with an active transponder;

- the sensor of the presence or spatial position of one or more counterweight loads is made electromechanical - in the form of a limit switch, a set of limit switches, a potentiometer with a transmission device, a linear encoder or other device made with the possibility of mechanical interaction with the load of the counterweight;

- the digital computer is configured to detect the movement of the mobile or additional removable counterweight to the transport position and the corresponding formation and transmission to the actuator signal of limiting the transport speed of the crane.

This embodiment of the load limiter of the jib crane allows during its operation with manual or automated control to take into account the influence of the counterweight both on its own and on the load stability of the crane. This ensures increased safety and efficiency of the crane due to the optimization of the shoulder (departure) and the mass of the counterweight for the most efficient balancing of the moment from the mass of mechanisms and metal structures of the crane and part of the moment from the lifted and transported cargo.

The drawing shows a simplified block diagram of a limiter.

The load limiter of the jib crane, which can also be called a device, controller, device or security or safety system, contains a digital computer 1, to the information inputs of which sensors 2 of the crane parameters are connected, and to the outputs - an actuator 3.

The digital computer 1, which can also be called a data processing unit, an indication unit, a controller, an operator panel, etc., is implemented on the basis of a microcontroller 4 to which an information display device 5, non-volatile storage device 6, controls 7 and an input device are connected / output information 8. The digital computer 1 may additionally include a sound alarm device, a real-time clock and other limiter functional units connected directly to the micro controller 4 or to the input / output device information 8.

The controls 7 are made in the form of a set of buttons / keys, switches, a touch screen display - information display device 5, etc.

The information display device 5 may be located in or outside the digital computer 1 and may contain both symbolic and graphic, for example, liquid crystal TFT, an indicator (display) and / or a set of LED indicators.

The input / output device information 8 provides coordination of the logical levels of the input and output signals of the microcontroller 4 with other functional devices of the limiter. Data transfer in the limiter, depending on the version of the information input / output device 8 and the interface circuits of the sensors 2 connected to it, is carried out on a radial circuit using separate wires, on a multiplex data exchange channel (CAN, LIN, RS-485, etc. etc.) and / or over the air (ZigBee, Bluetooth, Wi-Fi, etc.).

Actuator 3, which may also be called an output or power unit, an expansion unit, an output controller, etc., is made in the form of a set of power relays or electronic keys connected to electro-hydraulic or electromechanical actuators of the crane drives. If necessary, it may contain a microcontroller and an interface circuit for wired or wireless communication with a digital computer 1.

The set of sensors 2 depends on the implementation of the proposed limiter and on the type of crane - tower or self-propelled, with a telescopic or trellised boom, with a hydraulic or cable drive of the boom lifting mechanism, etc. Sensors 2 include a crane load sensor 9 (a force sensor in a boom or cargo cable or pressure sensors in a boom lifting hydraulic cylinder), sensors for the spatial position of the boom and load-gripping body 10 (tilt angle and length of the boom, angle of rotation of the turntable of the crane, maximum lifting) load-gripping body, etc.) and the sensor (s) for the presence and / or position of the counterweight as a whole or its individual loads 11. The limiter may also include a wind sensor 12, a proximity sensor to the power line, yes Chiki provisions of the manual control of executive bodies of the crane mechanisms, sensors provisions crane outriggers and other sensors.

Sensors 2 can be grouped according to their location on a crane, for example, on the head of a telescoping boom, on a fixed part of a crane, etc. In this case, each group of sensors is equipped with a controller that performs amplification, normalization, filtering, thermal compensation and lanerization of the sensor signals before transmitting them to the digital computer 1.

The sensor 11 of the presence or spatial position of the load of the counterweight on the counterweight console or on the rotary platform of the crane can be performed using contactless identification technology (RFID). In this case, a transponder or identifier is attached to each load of the counterweight - an active or passive RFID tag, and on the counterweight console or on the rotary platform of the crane, in the immediate vicinity of the standard location of the load of the counterweight, a tag reader is connected to the information input / output device 8.

If the individual counterweight loads in the transport and operating states of the crane are in different positions, then the limiter may contain two or more RFID tag readers, which allows you to determine the spatial position of these loads, in particular, their translation into the working or transport position.

The transponder or identifier of each cargo of the counterweight (RFID tag of each cargo) can contain and transmit to the reader, upon request, information recorded in this tag about the mass of the cargo and / or its regular place of installation on the counterweight console or on the rotary platform of the crane. This allows the digital computer 1 to identify the correct assembly of the set-up counterweight (a set of cast-iron or concrete beams or counterweight plates). The obtained information about the presence in the regular place and weight of each load of the counterweight is used by the microcontroller 4 of the digital computer 1 to adjust the information, warning and blocking signals generated by it and the control of the crane drives.

The sensor 11 for the presence or spatial position of one or more counterweight loads can be made in the form of a non-contact ultrasonic, capacitive, inductive, optical or radar range finder with signal reflection directly from the load, using a passive signal reflector or an active transponder attached to the load of the counterweight. This sensor (or a set of sensors) 11 can also be electromechanical - in the form of a limit switch, a set of limit switches, a potentiometer with a transmission device, a linear encoder or other device made with the possibility of mechanical interaction with the load of the counterweight. In this case, the measurement of the angular position of any element of the crane or of the counterweight itself can be used if this angular position affects the counterweight arm or is interconnected with its linear position.

The load limiter jib crane operates as follows.

Before starting the operation of the crane in memory 6 or in the memory of the microcontroller 4 of the digital calculator 1, preliminary in the form of formulas - subprograms of the microcontroller developed using the mathematical model of the crane, or in the form of tables the permissible loads of the crane for various spatial positions of its boom and load-bearing are recorded body and for different spatial positions of the counterweight or its individual loads in various modes of operation of the crane (with full or full support contour, with various boom equipment, etc.). Permissible loads of the crane are also established taking into account the wind load acting on the crane.

The operator (crane operator) using controls 7 enters into the memory of the microcontroller 4 parameters of the coordinate protection constraints (parameters of the zone of permissible positions of the boom equipment, load gripping body and counterweight) of the crane, as well as parameters of the crane itself, which characterize its geometry, conditions and operating mode . These include the type of boom equipment used (presence, length and angle of inclination of the jib), characteristics of the support contour, etc.

The microcontroller 4 operates according to the program recorded in its built-in program memory or in the storage device 6, and through the input / output device information 8 exchanges information with the sensors 2 of the parameters of the crane. After receiving information from the sensors 2, the microcontroller 4 determines the actual value of the current load of the crane, the actual position of the lifting (boom) equipment of the crane and the stock of its cargo stability. To determine them, if necessary, the necessary transformations of the output signals of sensors 2 are carried out. This takes place when the current load of the crane and / or the position of the lifting (boom) equipment are measured indirectly, for example, when determining the load of a hydraulic crane using pressure in the rod and the piston cavities of the boom lift hydraulic cylinder.

Next, the microcontroller 4 of the digital computer 1 compares the actual crane loading with the maximum permissible, as well as compares the actual position of the lifting (boom) equipment with its permissible positions, and, depending on the results of these comparisons, gives a signal to the actuator 3 to allow or prohibit individual types of crane movements.

In addition, the digital computer 1 controls the presence and position in a regular place on the counterweight console or on the rotary platform of the counterweight crane (or individual weights of the stacked counterweight) and, if necessary, generates and transmits to the actuator 3 signals for automatic control of the movement drive (moving or folding) counterweight or its individual cargoes. In this case, an increase / decrease in the shoulder (departure) of the counterweight is carried out if at the current moment the increase / decrease in the mass of the load on the load-gripping body (hook) or the load moment is detected. Additionally, pre-emptive generation of automatic control signals of the counterbalance drive can be performed, aimed at increasing its shoulder when the operator's command to translate the crane into a state of lower load stability is detected, for example, a command to lower the boom or turn the crane to lower stability.

The automatic control of the position of the counterweight or its individual loads is carried out, in the General case, taking into account the simultaneous achievement of both the necessary margin of own and / or cargo stability of the crane against tipping, and preventing collision of the counterweight with obstacles when the crane is operating in cramped conditions (in accordance with the parameters or the coordinates of these obstacles, previously recorded by the operator from the controls 7 in the memory of the digital computer 1).

This ensures that the crane is protected from overload and from collisions with various obstacles (coordinate protection), taking into account the presence of counterweight loads on the counterweight console or on the rotary platform of the crane, as provided for by the construction of the crane, the position of the counterweight loads (shoulder or counterweight departure), as well as the magnitude and wind speed.

If the design of the lifting crane provides for the movement of a mobile or additional removable counterweight to the transport position (for example, on automobile cranes KS-55721, KS-55729-1B, etc.), then digital computer 1 additionally generates a signal to limit the transport speed of the crane, if after the end of its work, this counterweight is not moved to the transport position. The level of limiting the transport speed of the crane is previously recorded in the memory of the digital computer 1 or is determined by it based on the safety requirements for the movement of the crane.

Simultaneously with the generation of signals to the actuator 3, the digital computer 1 gives signals to the information display device 5, informing the operator about the parameters of the crane, warning the operator about the occurrence of potentially dangerous situations, and also containing information of a recommendatory nature about the need or feasibility of performing any operations crane control, in particular changes in the spatial position of the counterweight.

To document the operation of the crane, the limiter may include an external or built-in parameter recorder, implemented on the basis of a storage device 6, in which the microcontroller 4 records the values of the main operating parameters of the crane (value of the load moment, tilt angle and length of the boom, etc.), warning signals and crane control signals for the purpose of their subsequent reading to analyze the efficiency of the crane and to investigate the causes of possible failures and accidents.

In this description, only partial embodiments of the proposed jib crane load limiter are schematically shown. The invention covers other possible variants of its execution and their equivalents without deviating from the essence of the invention set forth in its formula.

Claims (14)

1. The load limiter of the jib crane, containing sensors mounted on the crane and made with the possibility of measuring parameters characterizing the load, the spatial position of its boom and / or load-lifting body and the spatial position of the counterweight, an actuator and a digital computer connected to it, configured to receive and processing the output signals of the sensors and determining the current value of the load of the crane, comparing the current value of the load with the maximum allowable load, p pre-recorded in its storage device, as well as with the possibility of generating a warning signal and / or transmitting to the actuator a signal blocking the movements of the crane aimed at preventing its overload, characterized in that the sensor of the spatial position of the counterweight is made in the form of a sensor of presence and / or spatial position one or more loads of a removable or movable counterweight on the counterweight console or on the rotary platform of the crane, and a digital computer configured to generate an additional warning signal about the absence and / or spatial position of the load or cargo of the counterweight, reducing the crane's load stability, and / or to formulate recommendations to the crane operator about the need or feasibility of changing the spatial position of the cargo or cargo of the counterweight, and / or generate automatic control signals a drive for moving cargo or counterbalanced cargo from the condition of ensuring the safety of the crane. 2. The limiter according to claim 1, characterized in that it further comprises at least one discrete light and / or sound and / or symbolic and / or graphic indicator or display connected to or included in a digital computer structure. 3. The limiter according to claim 1, characterized in that the digital computer is configured to generate and transmit to the output device signals of automatic control of the counterbalance drive, aimed at increasing / decreasing its shoulder when it is detected at the current time that the load weight is increasing / decreasing on the load gripping body or cargo moment. 4. The limiter according to claim 1, characterized in that the digital computer is configured to generate and transmit to the output device signals of automatic control of the counterbalance drive, aimed at increasing its shoulder when the operator's command to translate the crane into a state of lower cargo stability, for example, a command to lower the boom or turn the crane in the direction of less stability. 5. The limiter according to claim 1, characterized in that the digital calculator is configured to generate and transmit to the output device automatic control signals of the counterweight movement drive from the condition of simultaneously achieving the crane’s own and / or load stability against tipping and preventing counterweight collisions with an obstacle in accordance with the parameters or coordinates of this obstacle, previously recorded in the memory of the digital computer. 6. The limiter according to one of claims 1 to 5, characterized in that it further comprises a speed and / or wind direction sensor connected to a digital computer, which is configured to take into account the direction and / or magnitude of the wind load on the crane at the specified warning the signal, and / or when the signal for blocking the movements of the crane or the movement of the counterweight is transmitted to the actuator, and / or when the signal for the automatic control of the counterbalance drive is transmitted to the actuator, and conditions increase the stability of the crane. 7. The limiter according to claim 1, characterized in that the values of the mass of the load or each load of the counterweight are pre-recorded in the memory of the digital computer and taken into account in its program of work. 8. The limiter according to claim 1, characterized in that the sensor for the presence or spatial position of at least one load of the counterweight is made using contactless identification technology in the form of a transponder attached to the cargo or identifier and a device for reading information from it. 9. The limiter of claim 8, characterized in that the transponder or identifier of the cargo is configured to store and transmit information about the mass of the cargo and / or its installation location, and the information reader is configured to transmit this information to a digital computer, which is adapted to change the program of their work in accordance with the information received. 10. The limiter according to claim 1, characterized in that the sensor of the presence or spatial position of one or more counterweight loads is made in the form of a non-contact ultrasonic, or capacitive, or inductive, or optical, or radar range finder. 11. The limiter of claim 10, wherein the range finder is made with a passive signal reflector or with an active transponder. 12. The limiter according to claim 1, characterized in that the sensor for the presence or spatial position of one or more counterweight cargoes is electromechanical. 13. The limiter according to claim 12, characterized in that the presence or spatial position sensor is made in the form of a limit switch, or a set of limit switches, or a potentiometer with a transmission device, or a linear encoder, or other device made with the possibility of mechanical interaction with the load of the counterweight . 14. The limiter according to any one of claims 1 to 5 or 7-13, characterized in that the digital computer is configured to detect the movement of the mobile or additional removable counterweight to the transport position and the corresponding generation and transmission to the actuator of a signal to limit the transport speed of the crane. .