CN110526119B - Crane supporting leg extension length measuring device and method and crane - Google Patents
Crane supporting leg extension length measuring device and method and crane Download PDFInfo
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- CN110526119B CN110526119B CN201910695801.7A CN201910695801A CN110526119B CN 110526119 B CN110526119 B CN 110526119B CN 201910695801 A CN201910695801 A CN 201910695801A CN 110526119 B CN110526119 B CN 110526119B
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- leg
- crane
- supporting leg
- length
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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
- B66C13/16—Applications of indicating, registering, or weighing devices
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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
- B66C15/00—Safety gear
Abstract
The invention relates to the technical field of industry, and discloses a device and a method for measuring the extension length of a crane supporting leg and a crane, which can solve the problem that a worker cannot accurately know the extension length of the supporting leg after the crane supporting leg is subjected to electrodeless extension and contraction.
Description
Technical Field
The invention relates to the technical field of industry, in particular to a device and a method for measuring the extension length of a crane supporting leg and a crane.
Background
At present, the movable supporting legs of the automobile crane mainly have two states of half-stretching and full-stretching, namely the length of the movable supporting legs extending out of the fixed supporting legs is half of the total stretching length or the whole total stretching length of the movable supporting legs, as shown in figure 1, the movable supporting legs possibly face the jiong environment with insufficient full-stretching space and insufficient half-stretching lifting capacity in some narrow construction sites, at the moment, the movable supporting legs need to be controlled to perform stepless stretching, and a scheme for efficiently and accurately detecting the stretching length of the supporting legs is absent at present.
Disclosure of Invention
The invention aims to provide a device and a method for measuring the extension length of a crane supporting leg and a crane.
In order to achieve the above object, the present invention provides a crane leg extension length measuring device, the leg including a movable leg and a fixed leg, the device including: the two-dimensional codes are arranged on one side of the movable supporting leg, wherein each two-dimensional code in the two-dimensional codes corresponds to one telescopic length parameter of the supporting leg; the decoder is arranged at the opening of the fixed supporting leg and used for scanning and decoding the two-dimensional code positioned at the opening to obtain the expansion length parameter of the two-dimensional code at the opening when the expansion or contraction of the movable supporting leg is finished; or
The two-dimensional codes are arranged inside the fixed supporting leg, wherein each two-dimensional code in the two-dimensional codes corresponds to one telescopic length parameter of the supporting leg;
the decoder is arranged at the tail part of the movable supporting leg and used for scanning and decoding the two-dimensional code corresponding to the decoder to obtain the expansion length parameter of the two-dimensional code when the movable supporting leg is completely expanded or contracted; and the calculation unit is used for obtaining the current extending length of the supporting leg according to the telescopic length parameter.
Optionally, the plurality of two-dimensional codes arranged on one side of the movable supporting leg are pasted on the telescopic areas on the movable supporting leg.
Optionally, the two-dimensional codes arranged inside the fixed support leg are pasted on the fixed support leg corresponding to the maximum length range in which the telescopic area of the movable support leg can be stretched.
Optionally, the apparatus further comprises: the signal transmission module is used for transmitting the telescopic length parameter decoded by the decoder to the computing unit; and transmitting the current extending length of the supporting leg obtained by the calculating unit to a display of the crane, so that the display displays the current extending length of the supporting leg.
Optionally, the signal transmission module transmits the telescopic length parameter and the current extension length of the supporting leg in at least one of the following manners: wire harness transmission, WIFI wireless transmission, Bluetooth transmission and radio frequency transmission.
Correspondingly, the invention also provides a crane, which comprises the crane supporting leg extension length measuring device. The crane further comprises: the device comprises a measuring unit, an alarm unit and an actuating mechanism, wherein the measuring unit is used for measuring the lifting moment of a lifting arm when the crane lifts and carries an object; the computing unit is further configured to: calculating the current rated lifting moment of a lifting arm of the crane according to the current extending length of the supporting leg; calculating a moment threshold value M; the alarm unit is used for sending out an alarm signal when the hoisting moment exceeds the rated hoisting moment and does not exceed the moment threshold value M; and the actuating mechanism is used for executing the cutting action on the crane when the hoisting moment exceeds the moment threshold value M.
Optionally, the expression of the torque threshold M is:
m is rated load moment x (1+ Δ),
where Δ is the fault limit.
Correspondingly, the invention also provides a method for measuring the extension length of the crane support leg, which is implemented based on the device for measuring the extension length of the crane support leg, and comprises the following steps: scanning and decoding the two-dimensional code corresponding to the decoder when the extension or contraction of the movable support leg is completed to obtain a telescopic length parameter of the two-dimensional code; and obtaining the current extension length of the supporting leg according to the telescopic length parameter.
According to the technical scheme, after the movable supporting leg of the crane is expanded or contracted, the two-dimensional codes at the opening of the fixed supporting leg in the plurality of two-dimensional codes arranged on one side of the movable supporting leg are scanned to obtain the expansion length parameters of the two-dimensional codes at the opening, and then the current extension length of the supporting leg is obtained through calculation.
Additional features and advantages of the invention will be set forth in the detailed description which follows.
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 specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:
fig. 1 is a schematic diagram of a crane leg in a half-extended state and a full-extended state.
Fig. 2 is a block diagram of a crane leg extension length measuring device according to an embodiment of the present invention.
Fig. 3 is a schematic diagram of a decoder according to an embodiment of the present invention.
Fig. 4 is a schematic view of measuring leg extension length using a terminal block.
Fig. 5 is a block diagram of a crane leg extension length measuring device according to another embodiment of the present invention.
Fig. 6 is a crane according to an embodiment of the present invention.
Fig. 7 is a flowchart of a method for measuring the extending length of a crane leg according to an embodiment of the present invention.
Description of the reference numerals
1 fixed supporting leg, 2 movable supporting leg, 3 horizontal oil cylinder and 4 vertical oil cylinder
5-support-pin 6 two-dimensional code 7 decoder
Detailed Description
The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.
Fig. 2 is a block diagram of a crane leg extension length measuring device provided by an embodiment of the invention, wherein a leg comprises a movable leg and a fixed leg, the device comprises: the system comprises a plurality of two-dimensional codes arranged on one side of a movable supporting leg, wherein each two-dimensional code in the plurality of two-dimensional codes corresponds to one telescopic length parameter of the supporting leg; the decoder is arranged at the opening of the fixed supporting leg and used for scanning and decoding the two-dimensional code positioned at the opening to obtain the expansion length parameter of the two-dimensional code at the opening when the expansion or contraction of the movable supporting leg is finished; and the calculation unit is used for obtaining the current extension length of the supporting leg according to the telescopic length parameter.
A plurality of two-dimensional codes can be pasted in the telescopic area on the movable supporting leg and are parallel to the telescopic direction of the telescopic area of the movable supporting leg. The telescopic area on the movable supporting leg is the maximum length of the movable supporting leg which can be drawn out of the fixed supporting leg or can be retracted into the fixed supporting leg. When the crane works, the movable supporting leg is extended out by the manipulator-operated supporting leg operating mechanism, specifically, as shown in fig. 3, the horizontal oil cylinder 3 provides power for extension or contraction of the movable supporting leg 2, the vertical oil cylinder 4 provides power for height adjustment of the supporting leg, and the ground provides support for the supporting leg by contacting with the supporting leg plate 5 of the supporting leg, so that the extension or contraction state of the crane supporting leg is achieved. Every two-dimensional code in a plurality of two-dimensional codes 6 corresponds a flexible length parameter of landing leg, and activity landing leg extends or contracts after accomplishing, and decoder 7 scans and decodes the flexible length parameter of the two-dimensional code that lies in the opening part in a plurality of two-dimensional codes 6 in order to obtain the two-dimensional code of opening part, and this flexible length parameter can be the distance of flexible regional head end of activity landing leg and opening part, then the calculating unit calculates the current extension length of landing leg according to this distance and combination landing leg each parts's structure parameter.
Another embodiment of a crane leg extension measuring device is provided below. A plurality of two-dimensional codes can set up in the inside of the fixed leg that the maximum length scope that can stretch out and draw back with the scalable region of activity landing leg corresponds, the decoder sets up in the activity landing leg afterbody, the rightmost end of activity landing leg in figure 3 promptly, after the activity landing leg extension or shrink is accomplished, the decoder that is located the activity landing leg afterbody scans and decodes the inside two-dimensional code of fixed leg relative with this decoder position, in order to obtain the flexible length parameter of two-dimensional code, this flexible length parameter can be for the fixed leg position that activity landing leg afterbody was located when the activity landing leg totally shrinks into fixed leg and the distance between the fixed leg position that current two-dimensional code was located, then the calculating unit can calculate the current length of stretching out of landing leg according to this distance and the structural parameter that combines.
The plurality of two-dimensional codes may be designed to have a minimum size that can be scanned and recognized by the decoder, and each two-dimensional codes are closely arranged to reduce an error in the measured current extension length of the leg.
As an alternative embodiment, the leg extension may also be measured using a pull box. As shown in fig. 4, the pull line box is arranged at the opening of the fixed supporting leg, the line head of the pull line box is fixed at the head end of the movable supporting leg, and the extension length of the supporting leg can be obtained according to the length of a pull line of the pull line box after the movable supporting leg is stretched.
According to the embodiment of the invention, aiming at the problem that a worker cannot accurately know the extension length of the supporting leg after the crane supporting leg is subjected to electrodeless extension or contraction, the two-dimensional code corresponding to the extension length parameter of the supporting leg is scanned and decoded to obtain the corresponding extension length parameter of the supporting leg after the crane movable supporting leg is extended or contracted, and then the current extension length of the supporting leg is obtained through calculation.
Fig. 5 is a device for measuring the extending length of a crane leg according to another embodiment of the present invention, which has a similar structure and function to the device for measuring the extending length of a crane leg described above, except that a signal transmission module is added for transmitting the telescopic length parameter decoded by the decoder to the computing unit.
It can be understood that the decoder scans and decodes the corresponding two-dimensional code, then outputs the stretching length parameter in the form of a digital signal, and then sends the stretching length parameter to the computing unit through the signal transmission module so as to calculate and obtain the current extending length of the supporting leg. After obtaining the current extension length of the leg, the calculation unit may send the extension length to a display of the crane, so that the display displays the current extension length of the leg. Wherein, the computing unit can send the current extension length of the supporting leg to the display through the signal transmission module.
The manner of the signal transmission module transmitting the telescopic length parameter and the current extension length data of the supporting leg may include: wire harness transmission, WIFI wireless transmission, Bluetooth transmission and radio frequency transmission.
The device for measuring the extension length of the crane support leg according to the embodiment of the invention further comprises a signal transmission module for transmitting signals to obtain the current extension length of the support leg.
FIG. 6 is a block diagram of a crane according to an embodiment of the present invention, the crane includes the above-mentioned device for measuring the length of the outrigger of the crane, and further includes a measuring unit, an alarm unit and an actuator, the measuring unit is used for measuring the lifting moment of the boom when the crane is used to lift an object; the computing unit is further to: calculating the current rated lifting moment of a lifting arm of the crane according to the current extension length of the supporting leg; calculating a moment threshold value M; the alarm unit is used for sending out an alarm signal when the hoisting torque exceeds the rated hoisting torque and does not exceed a torque threshold value M; and the actuating mechanism is used for executing the cutting action on the crane when the hoisting moment exceeds a moment threshold value M.
It can be understood that after the current extension length of the supporting leg is obtained, the maximum torque of the object which can be currently lifted by the crane can be calculated according to the boom structure and the position parameters of the crane, the maximum torque is used as the current rated lifting torque, and the torque threshold value M is calculated according to the rated lifting torque. And meanwhile, the hoisting moment of the crane boom is measured when the crane hoists objects, the hoisting moment, the rated hoisting moment and the moment threshold value M are transmitted to the control room, and if the hoisting moment exceeds the rated hoisting moment, the crane is limited by the moment limiter of the crane to perform hoisting action, so that the hoisting safety is ensured, and manual operation errors can be avoided. More specifically, if the lifting moment exceeds the rated lifting moment but does not exceed the moment threshold value M, the alarm unit sends out an alarm signal; and if the hoisting moment exceeds the moment threshold value M, the actuating mechanism cuts off the action, and the crane stops working. The moment threshold value M may be in a range of 5% to 10% above the rated lifting moment, and may be specifically expressed by the formula:
m is rated load moment x (1+ Δ),
where Δ is a failure limit, and Δ is 5% to 10%, preferably, the failure limit may be set to 10% empirically.
The boom structure and position parameters can comprise a boom pitching angle and a boom stretching length, and the measuring unit can comprise a decoder for measuring the boom stretching length, and the boom stretching length of the current crane can be obtained by scanning and decoding a two-dimensional code capable of representing the boom stretching length. The measuring unit may further comprise an angle sensor for measuring the boom pitch angle. In addition, the boom pitch angle can also be calculated according to the boom telescopic length obtained by measurement and a trigonometric function formula.
The crane provided by the embodiment of the invention comprises the crane supporting leg extension length measuring device, the function of the crane supporting leg extension length measuring device is similar to that of the crane supporting leg extension length measuring device provided by the embodiment, the difference is that the crane supporting leg extension length measuring device is used for measuring the lifting moment of a crane boom when the crane lifts an object, the rated lifting moment and the moment threshold value M are obtained by calculating the current extension length of the supporting leg obtained by calculating the crane supporting leg extension length measuring device, and finally, an alarm prompt or a fault protection action is given according to the magnitude relation of the lifting moment, the rated lifting moment and the moment threshold value M of the current crane boom, so that the lifting safety is ensured.
Fig. 7 is a method for measuring the extension length of a crane leg, which is implemented based on the device for measuring the extension length of a crane leg according to an embodiment of the present invention, and the method further includes:
and step S710, scanning and decoding the two-dimensional code corresponding to the decoder when the extension or the contraction of the movable support leg is completed to obtain the expansion length parameter of the two-dimensional code.
And S720, obtaining the current extending length of the supporting leg according to the telescopic length parameter.
Specifically, the two-dimensional codes are multiple, and for one method, the two-dimensional codes can be pasted on the telescopic areas on the movable supporting legs and are parallel to the telescopic directions of the telescopic areas on the movable supporting legs. The telescopic area on the movable supporting leg is the maximum length of the movable supporting leg which can be drawn out of the fixed supporting leg or can be retracted into the fixed supporting leg. The telescopic length parameter can be the distance between the head end of the telescopic area of the movable supporting leg and the opening, and then the current extending length of the supporting leg can be calculated according to the distance and by combining the structural parameters of all parts of the supporting leg.
For another method, a plurality of two-dimensional codes can be arranged in the fixed support leg corresponding to the telescopic maximum length range of the telescopic region of the movable support leg, the decoder is arranged at the tail part of the movable support leg, after the movable support leg is expanded or contracted, the decoder at the tail part of the movable support leg scans and decodes the two-dimensional codes in the fixed support leg corresponding to the decoder to obtain the telescopic length parameter of the two-dimensional codes, the telescopic length parameter can be the distance between the position of the fixed support leg at the tail part of the movable support leg and the position of the fixed support leg at which the current two-dimensional codes are positioned when the movable support leg is completely contracted into the fixed support leg, and then the calculation unit can calculate the current extending length of the support leg according to the distance and by combining the structural parameters.
The plurality of two-dimensional codes may be designed to have a minimum size that can be scanned and recognized by the decoder, and each two-dimensional codes are closely arranged to reduce an error in the measured current extension length of the leg.
After the telescopic length parameters are scanned and decoded, the telescopic length parameters are transmitted to a computing unit through at least one transmission mode of wire harness transmission, WIFI wireless transmission, Bluetooth transmission and radio frequency transmission to calculate the current extending length of the supporting leg, and then the calculated current extending length is transmitted to a display of the crane, so that the display displays the current extending length of the supporting leg.
The method of the embodiment of the invention has the advantages similar to those of the device for measuring the extending length of the support leg of the crane of the embodiment, and the description is omitted.
The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.
It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. The invention is not described in detail in order to avoid unnecessary repetition.
In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.
Claims (9)
1. A crane leg extension length measuring device, the leg comprising a movable leg and a fixed leg, the device comprising:
the two-dimensional codes are arranged on one side of the movable supporting leg, wherein each two-dimensional code in the two-dimensional codes corresponds to one telescopic length parameter of the supporting leg;
the decoder is arranged at the opening of the fixed supporting leg and used for scanning and decoding the two-dimensional code positioned at the opening when the extension or contraction of the movable supporting leg is finished so as to obtain the expansion length parameter of the two-dimensional code at the opening; or
The two-dimensional codes are arranged inside the fixed supporting leg, wherein each two-dimensional code in the two-dimensional codes corresponds to one telescopic length parameter of the supporting leg;
the decoder is arranged at the tail part of the movable supporting leg and used for scanning and decoding the two-dimensional code corresponding to the decoder to obtain the expansion length parameter of the two-dimensional code when the movable supporting leg is completely expanded or contracted; and
and the computing unit is used for obtaining the current extending length of the supporting leg according to the telescopic length parameter.
2. The apparatus of claim 1, wherein the plurality of two-dimensional codes disposed on one side of the movable leg are attached to a stretchable region on the movable leg.
3. The apparatus of claim 1, wherein the plurality of two-dimensional codes disposed inside the fixed leg are attached to the fixed leg corresponding to a maximum length range in which the telescopic region of the movable leg can be extended and contracted.
4. The apparatus of claim 1, further comprising:
a signal transmission module for:
transmitting the scalable length parameter decoded by the decoder to the computing unit; and
and transmitting the current extending length of the supporting leg obtained by the calculating unit to a display of the crane, so that the display displays the current extending length of the supporting leg.
5. The apparatus of claim 4, wherein the signal transmission module transmits the telescoping length parameter and the current extension length of the leg in at least one of: wire harness transmission, WIFI wireless transmission, Bluetooth transmission and radio frequency transmission.
6. A crane comprising a crane leg extension measuring device according to any one of claims 1 to 5, the crane further comprising: a measuring unit, an alarm unit and an actuating mechanism,
the measuring unit is used for measuring the lifting moment of a lifting arm when the crane lifts and carries an object;
the computing unit is further configured to:
calculating the current rated lifting moment of a lifting arm of the crane according to the current extending length of the supporting leg;
calculating a moment threshold value M;
the alarm unit is used for sending out an alarm signal when the hoisting moment exceeds the rated hoisting moment and does not exceed the moment threshold value M; and
and the actuating mechanism is used for executing a cutting action on the crane when the hoisting moment exceeds the moment threshold value M.
7. A crane according to claim 6,
the expression of the moment threshold value M is as follows:
m is rated load moment x (1+ Δ),
where Δ is the fault limit.
8. A crane according to claim 7,
Δ＝5％～10％。
9. a crane leg extension length measuring method, which is implemented based on the crane leg extension length measuring device according to any one of claims 1 to 5, and which comprises:
scanning and decoding the two-dimensional code corresponding to the decoder when the extension or contraction of the movable support leg is completed to obtain a telescopic length parameter of the two-dimensional code; and
and obtaining the current extension length of the supporting leg according to the telescopic length parameter.
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| CN201910695801.7A CN110526119B (en) | 2019-07-30 | 2019-07-30 | Crane supporting leg extension length measuring device and method and crane |
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| CN201910695801.7A CN110526119B (en) | 2019-07-30 | 2019-07-30 | Crane supporting leg extension length measuring device and method and crane |
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| CN111960279B (en) * | 2019-12-16 | 2023-02-17 | 中联重科股份有限公司 | Crane control method and device, crane, processor and storage medium |
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| CA2255111C (en) * | 1997-12-05 | 2004-11-23 | Grove U.S. L.L.C. | Aerial work platform with pothole and/or obstacle detection and avoidance system |
| EP1772415A3 (en) * | 2005-10-04 | 2008-09-03 | Liebherr-Werk Ehingen GmbH | Support device for a mobile crane |
| DE102010056584B4 (en) * | 2010-12-30 | 2018-03-29 | Asm Automation Sensorik Messtechnik Gmbh | Mobile work machine |
| CN102390779B (en) * | 2011-11-04 | 2014-01-29 | 三一重工股份有限公司 | Detection method and detection device for tipping state of crane |
| CN102424037A (en) * | 2011-11-11 | 2012-04-25 | 中联重科股份有限公司 | Engineering machinery and operation control method of support leg thereof |
| CN203532409U (en) * | 2013-11-07 | 2014-04-09 | 中联重科股份有限公司 | Extending and retracting state detection device of support leg |
| CN109484976A (en) * | 2018-12-08 | 2019-03-19 | 安徽柳工起重机有限公司 | Automobile crane supporting leg condition detector and supporting leg operating mode's switch detection method |
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