CN111994797B - Safety control method and system for aerial work platform - Google Patents

Safety control method and system for aerial work platform Download PDF

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Publication number
CN111994797B
CN111994797B CN202010947741.6A CN202010947741A CN111994797B CN 111994797 B CN111994797 B CN 111994797B CN 202010947741 A CN202010947741 A CN 202010947741A CN 111994797 B CN111994797 B CN 111994797B
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China
Prior art keywords
current signal
amplitude variation
aerial work
work platform
angle
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CN111994797A (en
Inventor
姚江淮
王晓飞
汤家升
刘振远
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XCMG Fire Fighting Safety Equipment Co Ltd
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XCMG Fire Fighting Safety Equipment Co Ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C13/00—Other constructional features or details
    • B66C13/18—Control systems or devices
    • B66C13/48—Automatic control of crane drives for producing a single or repeated working cycle; Programme control
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C13/00—Other constructional features or details
    • B66C13/16—Applications of indicating, registering, or weighing devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C15/00—Safety gear
    • B66C15/06—Arrangements or use of warning devices
    • B66C15/065—Arrangements or use of warning devices electrical
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F11/00—Lifting devices specially adapted for particular uses not otherwise provided for
    • B66F11/04—Lifting devices specially adapted for particular uses not otherwise provided for for movable platforms or cabins, e.g. on vehicles, permitting workmen to place themselves in any desired position for carrying out required operations
    • B66F11/044—Working platforms suspended from booms
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F17/00—Safety devices, e.g. for limiting or indicating lifting force
    • B66F17/006—Safety devices, e.g. for limiting or indicating lifting force for working platforms
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B19/00—Programme-control systems
    • G05B19/02—Programme-control systems electric
    • G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
    • G05B19/048—Monitoring; Safety

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Structural Engineering (AREA)
  • Automation & Control Theory (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Forklifts And Lifting Vehicles (AREA)

Abstract

The invention discloses a safety control method and a safety control system for an aerial work platform, relates to the field of engineering machinery, and aims to optimize the performance of the aerial work platform. The method comprises the following steps: acquiring a current signal output by an output port of the controller, wherein the current signal corresponds to the amplitude-variable length and the amplitude-variable angle of an operating arm of the aerial work platform; acquiring the amplitude variation angle and the amplitude variation length of the operating arm in real time by adopting a long angle sensor arranged on the operating arm; judging whether the operation of the operation arm is abnormal or not according to a preset corresponding relation between the first current signal and the amplitude variation angle and a preset corresponding relation between the second current signal and the amplitude variation length; and if the abnormality occurs, controlling the aerial work platform to send alarm information and/or stop the aerial work platform. The technical scheme effectively reduces or even avoids the occurrence of excessive amplitude and other dangerous actions.

Description

Safety control method and system for aerial work platform
Technical Field
The invention relates to the field of engineering machinery, in particular to a safety control method and system for an aerial work platform.
Background
In recent years, with the vigorous development of high-altitude industry, no matter building construction, shipbuilding or cleaning, the high-altitude operation platform is increasingly an indispensable auxiliary tool. The scaffold has obvious economic boundary points and application defects in the building engineering, particularly obvious safety, economy and efficiency defects compared with an aerial work platform in an aerial work building with the height of more than 10 meters. Data research shows that the development of domestic high-altitude operation platforms is far behind that of other developed countries in Europe and America, the number of high-altitude operation platforms in Europe and other developed countries is 8.2 per ten thousand at present, and only 0.3 per ten thousand at home, for the developed countries in Europe and America, the development space of the current high-altitude operation platforms in Europe and America is huge, and the high-altitude market space value in 2017 and 2020 is estimated to be as high as 305 billion.
The arm support action of the aerial work platform is realized through a hydraulic system. The hydraulic system can have abnormal phenomena in the working process. In this case, in order to ensure the safety of operation and equipment, the emergency situation is usually solved by powering off the whole vehicle by opening an emergency stop switch.
The inventor finds that at least the following problems exist in the prior art: the emergency stop switch of the existing aerial work platform needs manual operation, and when an abnormal condition occurs, workers often forget to turn off the emergency stop switch due to excessive tension, so that safety accidents are caused. Therefore, there is a need for an aerial work platform capable of reducing accidents caused by abnormal situations.
Disclosure of Invention
The invention provides a safety control method and a safety control system for an aerial work platform, which are used for optimizing the performance of the aerial work platform.
The embodiment of the invention provides a safety control method for an aerial work platform, which is characterized by comprising the following steps of:
acquiring a current signal output by an output port of the controller, wherein the current signal corresponds to the amplitude-variable length and the amplitude-variable angle of an operating arm of the aerial work platform;
acquiring the amplitude variation angle and the amplitude variation length of the operating arm in real time by adopting a long angle sensor arranged on the operating arm;
judging whether the operation of the operation arm is abnormal or not according to a preset corresponding relation between the first current signal and the amplitude variation angle and a preset corresponding relation between the second current signal and the amplitude variation length;
and if the abnormality occurs, controlling the aerial work platform to send alarm information and/or stop the aerial work platform.
In some embodiments, the operation of the operating arm is determined to be abnormal if at least one of:
the output port of the controller does not output a first current signal, and the amplitude variation angle detected by the long-angle sensor exceeds a first preset range;
the output port of the controller does not output a second current signal, and the amplitude variation length detected by the long-angle sensor exceeds a second preset range;
the controller outputs a first current signal at an output port, and the amplitude variation angle detected by the long-angle sensor exceeds a range matched with the first current signal;
and the output port of the controller outputs a second current signal, and the amplitude variation length detected by the long-angle sensor exceeds a range matched with the second current signal.
In some embodiments, the operation of the operating arm is determined to be abnormal if one of the following occurs: the first current signal does not correspond to the amplitude variation angle, and the second current signal does not correspond to the amplitude variation length.
The embodiment of the invention also provides a safety control system of the aerial work platform, which comprises:
an operating arm;
a long angle sensor mounted to the operating arm and configured to detect a luffing angle of the operating arm; and
and the controller is connected with the amplitude variation valve of the operating arm in a control mode and is configured to acquire the first current signal and the second current signal output by the amplitude variation valve.
According to the technical scheme provided by the embodiment of the invention, in the working process of the aerial work platform: the controller compares the amplitude variation length information and the amplitude variation angle information fed back by the long angle sensor with the current signal output by the corresponding port of the valve. When no output current exists at the port of the valve and the change value of the long-angle sensor exceeds the safe fluctuation range, the abnormal condition is shown at the moment, the controller controls the engine to flameout the output port, so that the engine is flameout, the hydraulic power is cut off actively, the action is forced to stop, and the personnel safety is ensured. The first current signal is output at the valve output port, the amplitude variation angle is not detected by the long angle sensor, or the second current signal is output at the control valve output port, the amplitude variation length is not detected by the long angle sensor, the controller cuts off the continuous action (the arm support stretches and the amplitude rises) in the dangerous direction, and meanwhile, the system alarms the fault of the long angle sensor, so that the occurrence of the super amplitude and other dangerous actions is effectively reduced and even avoided.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:
fig. 1 is a schematic flow chart of a safety control method for an aerial work platform according to an embodiment of the present invention;
FIG. 2 is a schematic control logic diagram of a safety control method for an aerial work platform according to an embodiment of the present invention;
fig. 3 is a schematic diagram of a signal connection part at a controller of the aerial work platform safety control system according to the embodiment of the invention.
Detailed Description
The technical solution provided by the present invention is explained in more detail with reference to fig. 1 to 3.
Referring to fig. 1, some embodiments of the present invention provide a safety control method for an aerial work platform, including the following steps:
and S10, acquiring a current signal output by an output port of the controller, wherein the current signal corresponds to the amplitude-variable length and the amplitude-variable angle of an operating arm of the aerial work platform.
The controller of the aerial work platform has four ports, PWM1, PWM2, PWM3, and PWM 4. The controller PWM1 acquires the current acquired by the amplitude changing valve when the operating arm retracts, the PWM2 port acquires the current acquired by the amplitude changing valve when the amplitude changing valve extends, the PWM3 port acquires the current acquired by the amplitude changing valve when the operating arm falls, and the PWM4 port acquires the current acquired by the amplitude changing valve when the operating arm rises.
And step S20, acquiring the amplitude variation angle and amplitude variation length of the operating arm in real time by adopting a long angle sensor installed on the operating arm.
The long angle sensor may employ the amplitude angle and amplitude length of the operating arm. The amplitude variation angle refers to the rotation angle of the operating arm relative to the aerial work platform. The variable-amplitude length refers to the length of the operation arm which extends out and retracts along the length direction of the operation arm.
And step S30, judging whether the operation of the operation arm is abnormal or not according to the preset corresponding relation between the first current signal and the amplitude variation angle and the preset corresponding relation between the second current signal and the amplitude variation length.
The following correspondence exists between the first current signal and the amplitude variation angle: when the first current signal is a fixed value, the amplitude variation angle is an angle interval. The specific size of the angle interval can be set according to actual working conditions.
The following correspondence exists between the second current signal and the amplitude variation length: when the second current signal is a fixed value, the amplitude variation length is a length interval. The specific size of the length interval can be set according to actual working conditions.
And when any one of the following conditions occurs, judging that the operation of the operation arm is abnormal: the first current signal does not correspond to the amplitude variation angle, and the second current signal does not correspond to the amplitude variation length.
And step S40, if the abnormality occurs, controlling the aerial work platform to send alarm information and/or stop.
The safety control method for the aerial work platform, which is provided by the technical scheme, can coexist with the original emergency stop switch of the safety control system for the aerial work platform. When an abnormal condition occurs, an operator adopts the emergency stop switch to stop the aerial work platform. When the operator neglects to turn off the emergency stop switch under various conditions, the safety control method of the aerial work platform provided by the technical scheme can be adopted for control.
In the working process of the aerial work platform: the controller compares the amplitude variation length information and the amplitude variation angle information fed back by the long angle sensor with the current signal output by the corresponding port of the valve. When no output current exists at the port of the valve and the change value of the long-angle sensor exceeds the safe fluctuation range, the abnormal condition is shown at the moment, the controller controls the engine to flameout the output port, so that the engine is flameout, the hydraulic power is cut off actively, the action is forced to stop, and the personnel safety is ensured. The first current signal is output at the valve output port, the amplitude variation angle is not detected by the long angle sensor, or the second current signal is output at the control valve output port, the amplitude variation length is not detected by the long angle sensor, the controller cuts off the continuous action (the arm support stretches and the amplitude rises) in the dangerous direction, and meanwhile, the system alarms the fault of the long angle sensor, so that the occurrence of the super amplitude and other dangerous actions is effectively reduced and even avoided.
In some embodiments, the operation of the operating arm is determined to be abnormal if one of the following occurs:
the first condition is as follows: the output port of the controller does not output a first current signal, and the amplitude variation angle detected by the long-angle sensor exceeds a first preset range.
Case two: and the output port of the controller does not output a second current signal, and the amplitude variation length detected by the long-angle sensor exceeds a second preset range.
Case three: the output port of the controller outputs a first current signal, and the amplitude variation angle detected by the long-angle sensor exceeds the range matched with the first current signal.
Case four: and the output port of the controller outputs a second current signal, and the amplitude variation length detected by the long-angle sensor exceeds a range matched with the second current signal.
Any one of the four conditions indicates that an abnormal condition occurs, and the aerial work platform needs to be controlled to send alarm information and/or stop.
Referring to fig. 2 and 3, a specific embodiment is described.
The length and angle change values of the long angle sensor are monitored in real time through a controller CAN1 port, and the current magnitude of the amplitude and the current magnitude of the telescopic valve are respectively controlled through the controller PWM1, PWM2, PWM3 and PWM4 ports, and feedback current detection is carried out. The port of the controller OUT2 is connected with an engine flameout control port; when the controller issues a shutdown command, the OUT2 port is de-energized and the engine shuts down, as shown in fig. 3. When no output exists at the amplitude-variable and telescopic PWM ports, and the valve is blocked due to the fault of the hydraulic valve, the long angle sensor detects that the length angle value of the arm support changes, and the controller compares the change value of the long angle sensor with the current of the valve port in real time. Under the condition that no feedback current exists in the valve port, when the variable quantity of the long-angle sensor exceeds the set range, the controller defaults to be a dangerous working condition at the moment, the OUT2 output current is cut off, the engine is flamed OUT, the hydraulic pressure is enabled to lose pressure, and then the dangerous condition is avoided.
When the amplitude and expansion valve PWM port has current feedback and the long angle sensor value does not change, the controller defaults to the failure of the long angle sensor, the controller cuts off the continuous action (the arm support stretches and the amplitude rises) in the dangerous direction, and the system gives an alarm. The whole control logic diagram is shown in fig. 2.
According to the technical scheme, the phenomenon of hydraulic valve control failure can be solved, safety accidents caused by hydraulic valve control failure of the diesel straight crank arm aerial work platform in the work process are eliminated, and the safety of aerial work is greatly improved.
The method comprises the following steps that a long angle sensor of an aerial work platform arm support is utilized to carry out real-time arm support state detection, a controller monitors current of a valve port in real time, when no output current exists at the controller port and the length angle of the arm support is obviously changed, a system is defaulted to be in a state that a hydraulic valve is out of control (valve clamping) and is in a rotating state, an engine flameout port is controlled, an engine is flameout, hydraulic power is cut off, and dangerous actions are stopped; when the output port of the controller valve has output current but the long angle sensor does not change, the system defaults to the fault of the long angle sensor, and the system gives an alarm to prohibit the action in the dangerous direction.
The embodiment of the invention provides a safety control system of an aerial work platform, which comprises an operating arm, a long-angle sensor and a controller.
The long angle sensor is mounted to the operating arm and configured to detect a luffing angle of the operating arm. The controller is connected with a variable amplitude valve of the operating arm in a control mode, and the controller is configured to collect a first current signal and a second current signal output by the variable amplitude valve.
In the description of the present invention, it is to be understood that the terms "central", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be considered as limiting the scope of the present invention.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: it is to be understood that modifications may be made to the technical solutions described in the foregoing embodiments, or equivalents may be substituted for some of the technical features thereof, but such modifications or substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (2)

1. A safety control method for an aerial work platform is characterized by comprising the following steps:
acquiring a first current signal and a second current signal output by an output port of a controller, wherein the first current signal and the second current signal respectively correspond to the amplitude variation angle and the amplitude variation length of an operating arm of the aerial work platform;
acquiring the amplitude variation angle and the amplitude variation length of the operating arm in real time by adopting a long angle sensor arranged on the operating arm;
judging whether the operation of the operation arm is abnormal or not according to the corresponding relation between the preset first current signal and the amplitude variation angle and the corresponding relation between the preset second current signal and the amplitude variation length;
if the high-altitude operation platform is abnormal, controlling the high-altitude operation platform to send alarm information and/or stop the high-altitude operation platform; wherein it is determined that the operation of the operation arm is abnormal if at least one of the following occurs:
the output port of the controller does not output a first current signal, and the amplitude variation angle detected by the long-angle sensor exceeds a first preset range;
the output port of the controller does not output a second current signal, and the amplitude variation length detected by the long-angle sensor exceeds a second preset range;
the output port of the controller outputs a first current signal, and the amplitude variation angle detected by the long-angle sensor exceeds the range matched with the first current signal;
the output port of the controller outputs a second current signal, and the amplitude variation length detected by the long-angle sensor exceeds the range matched with the second current signal.
2. An aerial work platform safety control system configured to perform the aerial work platform safety control method of claim 1, the aerial work platform safety control system comprising:
an operating arm;
a long angle sensor mounted to the operating arm and configured to detect a luffing angle and a luffing length of the operating arm; and
and the controller is connected with the amplitude variation valve of the operating arm in a control mode and is configured to acquire the first current signal and the second current signal output by the amplitude variation valve.
CN202010947741.6A 2020-09-10 2020-09-10 Safety control method and system for aerial work platform Active CN111994797B (en)

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Publication number Priority date Publication date Assignee Title
CN112859932A (en) * 2020-12-29 2021-05-28 江苏徐工工程机械研究院有限公司 Electric control system and method for aerial work platform
CN112850593B (en) * 2021-02-09 2022-08-12 江苏徐工工程机械研究院有限公司 Leveling control system and method for aerial work platform
CN118550234A (en) * 2024-05-22 2024-08-27 美通重工有限公司 Aerial work platform safety control method and system based on luffing angle

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CN102060245A (en) * 2009-11-12 2011-05-18 上海派芬自动控制技术有限公司 Moment limiter human-computer interface system
CN102145857B (en) * 2011-01-31 2013-10-23 徐州重型机械有限公司 Crane, and revolution controlling system and method thereof
CN105460809B (en) * 2014-12-17 2018-01-16 徐州重型机械有限公司 A kind of telescopic arm telescopic control system, method and crane
CN105417448A (en) * 2015-11-06 2016-03-23 湖北省专用汽车研究院 Luffing control system and luffing control method for fire-fighting aerial ladder truck
CN105480899A (en) * 2015-11-30 2016-04-13 徐州重型机械有限公司 Closed-loop self-adaptive control system of aerial working platform and method thereof
CN108408613A (en) * 2018-03-12 2018-08-17 徐州徐工随车起重机有限公司 A kind of protection of lorry-mounted crane transport vehicle all-position safety and remote diagnosis repair system
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CN111350935B (en) * 2020-04-17 2021-06-25 上海外高桥造船有限公司 Protection system for luffing mechanism of portal crane

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