CN106185629B - A kind of caterpillar crane hook height detecting system and its implementation - Google Patents
A kind of caterpillar crane hook height detecting system and its implementation Download PDFInfo
- Publication number
- CN106185629B CN106185629B CN201610782994.6A CN201610782994A CN106185629B CN 106185629 B CN106185629 B CN 106185629B CN 201610782994 A CN201610782994 A CN 201610782994A CN 106185629 B CN106185629 B CN 106185629B
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- Prior art keywords
- encoder
- hook
- auxiliary
- elevator
- principal arm
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Classifications
-
- 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
- B66C13/00—Other constructional features or details
- B66C13/18—Control systems or devices
- B66C13/22—Control systems or devices for electric drives
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
- B66C23/00—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes
- B66C23/88—Safety gear
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
- B66C2700/00—Cranes
- B66C2700/08—Electrical assemblies or electrical control devices for cranes, winches, capstans or electrical hoists
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
- B66C2700/00—Cranes
- B66C2700/08—Electrical assemblies or electrical control devices for cranes, winches, capstans or electrical hoists
- B66C2700/084—Protection measures
Abstract
The invention discloses a kind of caterpillar crane hook height detecting system and its implementation, it is characterized in that, including main control module, angular transducer, encoder, warning device and display module；The angular transducer is separately mounted on principal arm and auxiliary, is respectively used to detect the inclination angle of principal arm and auxiliary and is sent in main control module；The warning device is connected with main control module；The encoder and main control module, display module are communicated by CAN；The encoder includes the main encoder being arranged on the central shaft of master winch side and the secondary encoder being arranged on the central shaft of secondary elevator side.The beneficial effect that the present invention is reached：The present invention can be with real-time display suspension hook terrain clearance, and display precision is higher；Three circle protectors can be substituted simultaneously, realize three circle warning functions；Monitor elevator rotation during the system concrete operations in real time by encoder, reduce external interference, and only need the demarcation in rope woolding once, convenient and simple.
Description
Technical field
The present invention relates to a kind of caterpillar crane hook height detecting system and its implementation, belong to height detection technique
Field.
Background technology
Traditional crawler crane does not have suspension hook terrain clearance to show or show inaccuracy at present, and suspension hook terrain clearance is main
Estimated by rule of thumb by operating personnel, but can not see lift hook position for some special operation conditions, operating personnel, not know
Height under hook.
In the prior art, crawler crane does not have real-time display suspension hook terrain clearance substantially.There is only a few crawler crane
By installing other detection devices additional, to realize detection height under hook.Automatically control system and its control of object and ground distance
Method, it is placed in the man-machine interface and man-machine interface of driver's cabin by the rope stretching length-measuring appliance with Adding Direction-Judging Function
The programmable controller and angular transducer of coupling, the rope stretching length-measuring appliance with Adding Direction-Judging Function pass through CAN
It is connected with programmable controller, and one-way transmission signal is passed to it, programmable controller is unidirectional to man-machine interface by CAN
Transmission signal；Angular transducer is connected with programmable controller.
But this kind of method has some limitations：First, zero-bit mark will be carried out before each weight lifting of the system
Fixed, because when steel wire rope looseness, the detection means can not accurately detect Steel wire rope discharge amount.Secondly, in the system, hard rubber
Rubber tire is rolled with sliding up and down for steel wire rope, and the rolling of rubber wheel drives the rotation of encoder.It is but actual in order to protect
Steel wire rope is protected, typically all in coating lubricating oil fat thereon, this results in the slip between steel wire rope and hard rubber wheel, it is difficult to ensure that
The accurate rope stretching amount for detecting steel wire rope.
The content of the invention
To solve the deficiencies in the prior art, it is an object of the invention to provide a kind of caterpillar crane hook height detection system
System and its implementation, effectively improve the measurement to height under hook, and solution can only be estimated by vision in most cases at present
The problem of calculation.
In order to realize above-mentioned target, the present invention adopts the following technical scheme that：
A kind of caterpillar crane hook height detecting system, it is characterized in that, including main control module, angular transducer, coding
Device, warning device and display module；The angular transducer is separately mounted on principal arm and auxiliary, be respectively used to detect principal arm and
The inclination angle of auxiliary is simultaneously sent in main control module；The warning device is connected with main control module, when master winch and secondary elevator
The number of turns less than three circle when, warning device is alarmed；The encoder and main control module, display module are led to by CAN
News, encoder are used for the turnning circle for recording corresponding elevator in real time；The encoder includes being arranged on master winch side central shaft
On main encoder and the secondary encoder that is arranged on the central shaft of secondary elevator side.
Further, the main encoder and secondary encoder are each via shaft coupling, encoder installing plate and corresponding volume
Raise connection.
Further, it is provided with encoder protective cover outside the main encoder and secondary encoder.
A kind of implementation method based on above-described caterpillar crane hook height detecting system, it is characterized in that, including
Following steps：
1) in elevator rope woolding, when steel wire rope has just exposed wire rope handling mouth, start demarcate encoder, including encoder side to,
Individual pen resolution ratio, total resolution and preset currency.
2) elevator is operated, elevator, which rotates, drives encoder axis of rotation, the number of turns turned over by encoder record elevator, and
Calculate the rope capacity of master winch and each layer of secondary elevator；
3) current operating mode is combined according to the result of step 2), calculates main hook terrain clearance and auxiliary hook terrain clearance in real time；
4) corresponding main hook terrain clearance and auxiliary hook are liftoff when calculating master winch and secondary elevator less than three circles according to step 3)
Highly, the trigger value according to this value setting warning device is when master winch and secondary elevator are less than three circles, master control set output alarm
Signal, alarm work is triggered, while limit elevator and fall direction action.
Further, the rotating cycle value for main encoder current record being assumed in the step 2) is Nm, secondary encoder ought
The rotating cycle value of preceding record is Nf, the full layer coder rotating cycle of elevator one of wirerope-winding is Nd, wire rope radius r；
The 1st layer of rope capacity of master winch is LM1=2NmπR1；2nd layer of rope capacity is LM2=2 (Nm-Nd)πR2, its
Middle R2=R1+1.732r；N-th layer rope capacity is LMn=2 (Nm-(n-1)Nd)πRn, wherein Rn=R1+1.732(n-1)r；It is secondary
The 1st layer of rope capacity of elevator is LF1=2NfπR1；2nd layer of rope capacity is LF2=2 (Nf-Nd)πR2, wherein R2=R1+
1.732r；N-th layer rope capacity is LFn=2 (Nf-(n-1)Nd)πRn, wherein Rn=R1+ 1.732 (n-1) r, wherein, R1Table
Show master winch height R plus first layer wire rope radius r distance and.
Further, assume that master winch and main hook are corresponding in the step 3), secondary elevator and auxiliary hook are corresponding, the multiplying power of main hook
For Reev1, the multiplying power of auxiliary hook is Reev2, and master file steel wire rope total length is LT1, secondary coil cord total length is LT2, main hook pulley
Distance to hook bottom is H3, the distance of auxiliary hook pulley to hook bottom is H5, principal arm hinge is highly H from the groundo；
After selected operating mode, the distance L of master file to principal arm leading block1, pair is rolled onto principal arm leading block distance L2, principal arm length
Spend Lm, principal arm leading block to principal arm head pulley distance L3, principal arm leading block to auxiliary leading block distance is L4, auxiliary
Leading block to auxiliary head pulley distance be L5, auxiliary length is Lf；Principal arm head is set to the vertical of principal arm head pulley center
Distance is H1；The inclination angle of principal arm is α, and the inclination angle of auxiliary is β；
Then H2={ LT1-(LM1+LM2+...+LMn)-L1-L3}/Reev1；
Main hook terrain clearance Hm=Lm·sinα+Ho-H1-H2-H3；
H4={ LT2-(LF1+LF2+…+LFn)-L2-L4-L5}/Reev2；
Auxiliary hook terrain clearance Hf=Lm·sinα+Lf·sinβ+Ho-H4-H5。
The beneficial effect that the present invention is reached：The present invention can be with real-time display suspension hook terrain clearance, and display precision is higher；
Three circle protectors can be substituted simultaneously, realize three circle warning functions；Monitor volume during the system concrete operations in real time by encoder
Rotation is raised, reduces external interference, and only needs the demarcation in rope woolding once, convenient and simple.
Brief description of the drawings
Fig. 1 is the schematic diagram of the system；
Fig. 2 is elevator cross-sectional view；
Fig. 3 is arm support simplified model schematic diagram.
The implication of reference in figure：
1- master winches, 2- pair elevators, 3- principal arm leading blocks, 4- principal arms head pulley, 5- main hook pulleys, 6- auxiliarys are oriented to
Pulley, 7- auxiliarys head pulley, 8- auxiliary hook pulleys.
Embodiment
The invention will be further described below in conjunction with the accompanying drawings.Following examples are only used for clearly illustrating the present invention
Technical scheme, and can not be limited the scope of the invention with this.
The purpose of the present invention is to realize caterpillar crane hook height detection, real-time display suspension hook terrain clearance, and can be replaced
Protector, which is enclosed, for elevator three realizes three circle warning functions.
The system is the setting angle sensor on major and minor arm by installing encoder additional on major and minor elevator, coding
The angle value for angular displacement and the arm support change that device rotates is transported to controller, and suspension hook terrain clearance is calculated by control algolithm
Position is enclosed with elevator three.
Specifically include main control module, angular transducer, encoder, warning device and display module, wherein, display module
It can be arranged in the man-machine interface in driver's cabin, main control module is arranged in Electric Appliance Cabinet.
Angular transducer is used to detect the inclination angle of principal arm and auxiliary and is sent in main control module.When master winch 1 and pair
When the number of turns of elevator 2 is less than three circles, warning device is alarmed.
So-called encoder is a kind of device for angular displacement or straight-line displacement being converted into electric signal in the present invention.
The system comprises the following steps when specifically being operated：
1) encoder is arranged on the central shaft of major and minor elevator side, passes through shaft coupling and encoder installing plate and elevator
Connection, outside install encoder protective cover additional.In elevator rope woolding, when steel wire rope has just exposed wire rope handling mouth, start to demarcate encoder,
Including encoder side to, individual pen resolution ratio, total resolution and preset currency.
2) elevator is operated, elevator, which rotates, drives encoder axis of rotation, the number of turns turned over by encoder record elevator, and
Calculate the rope capacity of master winch 1 and each layer of secondary elevator 2.
As shown in Figure 2：Assuming that the rotating cycle value of main encoder current record is Nm, the rotation of secondary encoder current record
Number of turns value is Nf, the full layer coder rotating cycle of elevator one of wirerope-winding is Nd, wire rope radius r；
The 1st layer of rope capacity of master winch 1 is LM1=2NmπR1；2nd layer of rope capacity is LM2=2 (Nm-Nd)πR2,
Wherein R2=R1+1.732r；N-th layer rope capacity is LMn=2 (Nm-(n-1)Nd)πRn, wherein Rn=R1+1.732(n-1)r；
The 1st layer of rope capacity of secondary elevator 2 is LF1=2NfπR1；2nd layer of rope capacity is LF2=2 (Nf-Nd)πR2, wherein R2=R1
+1.732r；N-th layer rope capacity is LFn=2 (Nf-(n-1)Nd)πRn, wherein Rn=R1+1.732(n-1)r。
3) current operating mode is combined according to the result of step 2), calculates main hook terrain clearance and auxiliary hook terrain clearance in real time.
For convenience of description, such as Fig. 3.It is assumed that master winch 1 and main hook are corresponding, secondary elevator 2 and auxiliary hook are corresponding, the multiplying power of main hook
For Reev1, the multiplying power of auxiliary hook is Reev2, and master file steel wire rope total length is LT1, secondary coil cord total length is LT2, main hook pulley
The distance at 5 to hook bottom is H3, the distance of auxiliary hook pulley 8 to hook bottom is H5, principal arm hinge is highly H from the groundo。
After selected operating mode, the distance L of master file to principal arm leading block 31, pair is rolled onto the distance L of principal arm leading block 32, principal arm
Length Lm, principal arm leading block 3 arrives the distance L of principal arm head pulley 43, principal arm leading block 3 to auxiliary leading block 6 apart from for
L4, auxiliary leading block 6 to auxiliary head pulley 7 is apart from for L5, auxiliary length is Lf；Principal arm head is set to principal arm head pulley 4
The vertical range at center is H1；
Then H2={ LT1-(LM1+LM2+...+LMn)-L1-L3}/Reev1；
Main hook terrain clearance Hm=Lm·sinα+Ho-H1-H2-H3；
H4={ LT2-(LF1+LF2+...+LFn)-L2-L4-L5}/Reev2；
Auxiliary hook terrain clearance Hf=Lm·sinα+Lf·sinβ+Ho-H4-H5。
4) corresponding main hook terrain clearance and pair when master winch 1 encloses with secondary elevator 2 less than three are calculated according to step 3) formula
Hook terrain clearance, the trigger value according to this value setting warning device is when master winch 1 and secondary elevator 2 are less than three circles, master control set
Output alarm signal, alarm work is triggered, while limit elevator and fall direction action.
Encoder in the present invention can also be replaced by installing speed probe on motor.
Described above is only the preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, without departing from the technical principles of the invention, some improvement and deformation can also be made, these are improved and deformation
Also it should be regarded as protection scope of the present invention.
Claims (3)
1. a kind of implementation method of caterpillar crane hook height detecting system, it is characterized in that, the caterpillar crane hook is high
Degree detecting system includes main control module, angular transducer, encoder, warning device and display module；The angular transducer point
It An Zhuan not be respectively used to detect the inclination angle of principal arm and auxiliary and be sent in main control module on principal arm and auxiliary；The report
Alarm device is connected with main control module, and when the number of turns of master winch and secondary elevator is less than three circles, warning device is alarmed；It is described
Encoder and main control module, display module are communicated by CAN, and encoder is used for the turning collar for recording corresponding elevator in real time
Number；The encoder includes the main encoder being arranged on the central shaft of master winch side and is arranged on the central shaft of secondary elevator side
Secondary encoder；
Comprise the following steps：
1) in elevator rope woolding, when steel wire rope has just exposed wire rope handling mouth, start to demarcate encoder, including encoder side is to, individual pen
Resolution ratio, total resolution and preset currency；
2) elevator is operated, elevator, which rotates, drives encoder axis of rotation, the number of turns turned over by encoder record elevator, and calculates
The rope capacity of master winch and each layer of secondary elevator；
3) current operating mode is combined according to the result of step 2), calculates main hook terrain clearance and auxiliary hook terrain clearance in real time；
4) corresponding main hook terrain clearance and auxiliary hook terrain clearance when calculating master winch and secondary elevator less than three circles according to step 3),
Trigger value according to this value setting warning device is when master winch and secondary elevator are less than three circles, master control set output alarm signal,
Alarm work is triggered, while limits elevator and falls direction action.
2. a kind of implementation method of caterpillar crane hook height detecting system according to claim 1, it is characterized in that, institute
The rotating cycle value for stating hypothesis main encoder current record in step 2) is Nm, the rotating cycle value of secondary encoder current record is
Nf, the full layer coder rotating cycle of elevator one of wirerope-winding is Nd, wire rope radius r；
The 1st layer of rope capacity of master winch is LM1=2NmπR1；2nd layer of rope capacity is LM2=2 (Nm-Nd)πR2, wherein R2
=R1+1.732r；N-th layer rope capacity is LMn=2 (Nm-(n-1)Nd)πRn, wherein Rn=R1+1.732(n-1)r；Pair volume
It is LF to raise the 1st layer of rope capacity1=2NfπR1；2nd layer of rope capacity is LF2=2 (Nf-Nd)πR2, wherein R2=R1+
1.732r；N-th layer rope capacity is LFn=2 (Nf-(n-1)Nd)πRn, wherein Rn=R1+ 1.732 (n-1) r, wherein, R1Table
Show master winch highly plus first layer wire rope radius distance and.
3. a kind of implementation method of caterpillar crane hook height detecting system according to claim 1, it is characterized in that, institute
State and assume that master winch and main hook are corresponding in step 3), secondary elevator and auxiliary hook are corresponding, and the multiplying power of main hook is Reev1, the multiplying power of auxiliary hook
For Reev2, master file steel wire rope total length is LT1, secondary coil cord total length is LT2, the distance of main hook pulley to hook bottom is H3,
Auxiliary hook pulley to the distance at hook bottom be H5, principal arm hinge is highly H from the groundo；
After selected operating mode, the distance L of master file to principal arm leading block1, pair is rolled onto principal arm leading block distance L2, principal arm length Lm,
Principal arm leading block is to principal arm head pulley distance L3, principal arm leading block to auxiliary leading block distance is L4, auxiliary, which is oriented to, to be slided
It is L to take turns to auxiliary head pulley distance5, auxiliary length is Lf；Set principal arm head to principal arm head pulley center vertical range as
H1；The inclination angle of principal arm is α, and the inclination angle of auxiliary is β；
Then H2={ LT1-(LM1+LM2+...+LMn)-L1-L3}/Reev1；
Main hook terrain clearance Hm=Lm·sinα+Ho-H1-H2-H3；
H4={ LT2-(LF1+LF2+...+LFn)-L2-L4-L5}/Reev2；
Auxiliary hook terrain clearance Hf=Lm·sinα+Lf·sinβ+Ho-H4-H5。
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| Application Number | Priority Date | Filing Date | Title |
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| CN201610782994.6A CN106185629B (en) | 2016-08-31 | 2016-08-31 | A kind of caterpillar crane hook height detecting system and its implementation |
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| CN201610782994.6A CN106185629B (en) | 2016-08-31 | 2016-08-31 | A kind of caterpillar crane hook height detecting system and its implementation |
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| CN106185629B true CN106185629B (en) | 2017-11-28 |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109437019A (en) * | 2018-12-10 | 2019-03-08 | 中联重科股份有限公司 | Crane hook height control method, device and crane |
| EP3925920A4 (en) * | 2019-02-14 | 2022-11-23 | Tadano Ltd. | Dynamic-lift-off determination device, dynamic-lift-off control device, mobile crane, and dynamic-lift-off determination method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101780926A (en) * | 2010-01-07 | 2010-07-21 | 上海三一科技有限公司 | Crawler crane moment limiting system |
| CN201942463U (en) * | 2010-12-31 | 2011-08-24 | 徐州重型机械有限公司 | Crane and winding steel wire rope over-releasing-prevention protection device thereof |
| RU2457170C1 (en) * | 2011-03-11 | 2012-07-27 | Государственное образовательное учреждение высшего профессионального образования "Сибирская государственная автомобильно-дорожная академия (СибАДИ)" | Lifting crane control method and system for its realisation |
| CN103395696A (en) * | 2013-08-12 | 2013-11-20 | 徐州重型机械有限公司 | Hoisting height control system and method of crane |
| CN203602279U (en) * | 2013-12-13 | 2014-05-21 | 中联重科股份有限公司 | System for detecting pendency height of hook and crane |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0826671A (en) * | 1994-07-12 | 1996-01-30 | Tadano Ltd | Computation error warning device employed by hook ground clearance computation device for mobile crane |
| JPH08192991A (en) * | 1995-01-12 | 1996-07-30 | Hitachi Constr Mach Co Ltd | Lift measurement method of crane and device thereof |
-
2016
- 2016-08-31 CN CN201610782994.6A patent/CN106185629B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101780926A (en) * | 2010-01-07 | 2010-07-21 | 上海三一科技有限公司 | Crawler crane moment limiting system |
| CN201942463U (en) * | 2010-12-31 | 2011-08-24 | 徐州重型机械有限公司 | Crane and winding steel wire rope over-releasing-prevention protection device thereof |
| RU2457170C1 (en) * | 2011-03-11 | 2012-07-27 | Государственное образовательное учреждение высшего профессионального образования "Сибирская государственная автомобильно-дорожная академия (СибАДИ)" | Lifting crane control method and system for its realisation |
| CN103395696A (en) * | 2013-08-12 | 2013-11-20 | 徐州重型机械有限公司 | Hoisting height control system and method of crane |
| CN203602279U (en) * | 2013-12-13 | 2014-05-21 | 中联重科股份有限公司 | System for detecting pendency height of hook and crane |
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