CN110885046A - Overload-prevention lifting mechanism and control method thereof - Google Patents
Overload-prevention lifting mechanism and control method thereof Download PDFInfo
- Publication number
- CN110885046A CN110885046A CN201911371581.9A CN201911371581A CN110885046A CN 110885046 A CN110885046 A CN 110885046A CN 201911371581 A CN201911371581 A CN 201911371581A CN 110885046 A CN110885046 A CN 110885046A
- Authority
- CN
- China
- Prior art keywords
- arm
- folding arm
- connecting rod
- folding
- working platform
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000007246 mechanism Effects 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 12
- 230000002265 prevention Effects 0.000 claims description 18
- 238000004891 communication Methods 0.000 claims description 5
- 230000009471 action Effects 0.000 claims description 4
- 230000003028 elevating effect Effects 0.000 claims description 3
- 230000008859 change Effects 0.000 description 11
- 230000014509 gene expression Effects 0.000 description 7
- 238000010276 construction Methods 0.000 description 4
- 230000005484 gravity Effects 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- NAWXUBYGYWOOIX-SFHVURJKSA-N (2s)-2-[[4-[2-(2,4-diaminoquinazolin-6-yl)ethyl]benzoyl]amino]-4-methylidenepentanedioic acid Chemical compound C1=CC2=NC(N)=NC(N)=C2C=C1CCC1=CC=C(C(=O)N[C@@H](CC(=C)C(O)=O)C(O)=O)C=C1 NAWXUBYGYWOOIX-SFHVURJKSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000013178 mathematical model Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 102220187649 rs145044428 Human genes 0.000 description 1
Images
Classifications
-
- 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
- B66F11/046—Working platforms suspended from booms of the telescoping type
-
- 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
- B66C23/62—Constructional features or details
- B66C23/64—Jibs
- B66C23/68—Jibs foldable or otherwise adjustable in configuration
-
- 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
- B66C23/62—Constructional features or details
- B66C23/64—Jibs
- B66C23/70—Jibs constructed of sections adapted to be assembled to form jibs or various lengths
- B66C23/701—Jibs constructed of sections adapted to be assembled to form jibs or various lengths telescopic
-
- 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
- B66C23/62—Constructional features or details
- B66C23/82—Luffing gear
- B66C23/821—Bracing equipment for booms
- B66C23/826—Bracing equipment acting at an inclined angle to vertical and horizontal directions
-
- 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
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Structural Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Forklifts And Lifting Vehicles (AREA)
Abstract
The invention discloses an overload-prevention lifting mechanism which comprises a folding arm, a telescopic arm, a flying arm and a working platform, wherein the telescopic arm, the flying arm and the working platform are positioned above the folding arm, the folding arm comprises a folding arm upper arm and a folding arm lower arm, an amplitude-variable oil cylinder for lifting the folding arm upper arm is arranged on the folding arm lower arm, one end of the folding arm upper arm is hinged with one end of the telescopic arm, the other end of the telescopic arm is hinged with one end of the flying arm, the other end of the flying arm is hinged with the working platform, the other end of the folding arm upper arm is hinged with one end of the folding arm lower arm, a fixed base is arranged below the hinged position of one end of the folding arm upper arm and one end of the telescopic arm, and the other end of the folding arm lower arm. The overload-prevention lifting mechanism and the control method can monitor the load of the working platform, judge whether the load of the working platform exceeds a preset value or not and ensure the safety of the working platform.
Description
Technical Field
The invention relates to an overload prevention lifting mechanism and a control method thereof, belonging to the technical field of machinery.
Background
In the high-altitude operation, the installation and construction of some objects are often involved, for example, the installation and construction, maintenance and cleaning of glass curtain walls of some high buildings and the like are generally completed by matching a lifting mechanism with a working platform. The lifting mechanism generally comprises a folding arm, a telescopic arm and a fly arm, the pitching angles of the folding arm, the telescopic arm and the fly arm and the length of the telescopic arm can be changed through a hydraulic cylinder, the working platform is arranged at the top end of the lifting mechanism, and the working platform is lifted to a required working height through the lifting mechanism to carry out corresponding construction. The constructor stands on the working platform, and some tools and materials used for construction are also placed on the working platform, so that certain requirements are met on the load of the working platform. Under the condition that the weights of the telescopic boom, the fly jib and the working platform are fixed, if the load of the working platform is too large, the safety of the working platform is affected, and therefore the load of the working platform needs to be monitored and controlled.
Disclosure of Invention
The invention mainly solves the technical problem of providing an overload prevention lifting mechanism, wherein pressure change of a luffing oil cylinder of a folding arm in the overload prevention lifting mechanism is only related to monitoring the load of a working platform under the condition that the folding arm does not work, whether the load of the working platform exceeds a preset value is judged, and the safety of the working platform is ensured.
In order to solve the technical problems, the invention adopts the technical scheme that: the utility model provides an overload-proof lifting mechanism, it includes folding arm, flexible arm, fly jib and work platform are located folding arm top, folding arm includes folding arm upper arm and folding arm underarm, be provided with the variable amplitude hydro-cylinder that makes folding arm upper arm go up and down on the folding arm underarm, the one end of folding arm upper arm is articulated with the one end of flexible arm, the other end of flexible arm is articulated with the one end of fly jib, the other end of fly jib is articulated with work platform, the other end of folding arm upper arm is articulated with the one end of folding arm underarm, the one end of folding arm upper arm is provided with a fixed base with the below of the articulated department of one end of flexible arm, the other end of folding arm underarm with the base is articulated.
In a preferred embodiment of the invention, the upper folding arm comprises an upper folding arm connecting rod and a lower folding arm connecting rod, the lower folding arm comprises an upper folding arm connecting rod and a lower folding arm connecting rod, the upper folding arm connecting rod and the lower folding arm connecting rod are parallel, one end of the upper folding arm connecting rod and one end of the lower folding arm connecting rod are hinged with an upper triangular connecting piece respectively, the other end of the upper folding arm connecting rod and the other end of the lower folding arm connecting rod are hinged with a lower triangular connecting piece respectively, one end of the upper folding arm connecting rod and one end of the lower folding arm connecting rod are hinged with a lower triangular connecting piece respectively, the other end of the upper folding arm connecting rod and the other end of the lower folding arm connecting rod are hinged with the base respectively, the upper connecting rod of the upper arm of the folding arm, the lower connecting rod of the upper arm of the folding arm, the upper triangular connecting piece and the lower triangular connecting piece form a parallelogram connecting rod mechanism, and the upper connecting rod of the lower arm of the folding arm, the lower triangular connecting piece and the base form a parallelogram connecting rod mechanism.
In a preferred embodiment of the present invention, a connection line between a hinge point of the other end of the upper link of the lower arm of the folding arm and the base and a hinge point of the other end of the lower link of the lower arm of the folding arm and the base is located in the vertical direction.
In a preferred embodiment of the present invention, a connecting line between a hinge point of one end of the upper link of the upper arm of the folding arm and the upper triangular connecting member and a hinge point of one end of the lower link of the upper arm of the folding arm and the upper triangular connecting member is located in the up-down vertical direction.
In a preferred embodiment of the invention, the lower end of the luffing cylinder is hinged on a lower connecting rod of a lower arm of the folding arm, the top end of a piston rod of the luffing cylinder is hinged on an upper connecting rod of an upper arm of the folding arm, and a pressure sensor for detecting the pressure of the luffing cylinder is arranged in the luffing cylinder.
In a preferred embodiment of the invention, the device further comprises a control unit, and the pressure sensor is in communication connection with the control unit.
In a preferred embodiment of the invention, the foldable arm upper arm lower link control system further comprises an angle sensor for detecting the pitch angle of the upper link of the foldable arm and the lower link of the foldable arm, and the angle sensor is connected with the control unit in a communication mode.
The invention also provides a control method for the overload prevention lifting mechanism, which comprises the following steps:
(1) the pressure sensor detects the pressure value when the amplitude variation oil cylinder pushes the upper arm of the folding arm to act, and transmits a signal to the control unit of the lifting mechanism;
(2) the angle sensor detects the angle position of the lower arm or the upper arm of the folding arm and transmits the signal to the control unit of the lifting mechanism
(3) The control unit judges whether the pressure value of the luffing cylinder and the angle position of the folding arm exceed a preset value or not through the detected pressure value of the luffing cylinder and the detected angle position of the folding arm, if the pressure value exceeds the preset value, the load of the working platform in the lifting mechanism exceeds a set value, the working platform is in an overload state and limits the action of the working platform, and at the moment, the load of the working platform is reduced.
The invention has the beneficial effects that: the overload prevention lifting mechanism and the control method have the advantages that the pressure value of the movement of the luffing cylinder on the upper arm of the folding arm is only related to the weight of the part above the upper arm of the folding arm, the weight and angle change of the folding arm and the position size of the hinge point of the luffing cylinder, and is unrelated to the angle change of each structure above the upper arm of the folding arm, the load of the working platform can be monitored, so that the pressure value of the luffing cylinder and the angle of the folding arm have corresponding relation with the load of the working platform, when the pressure value of the luffing cylinder exceeds a preset value, the overload of the working platform can be judged, and the load of the working platform is reduced at the moment so as.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without inventive efforts, wherein:
fig. 1 is a schematic structural view of an overload prevention elevating mechanism of the present invention;
FIG. 2 is a schematic view of the folding arm of FIG. 1;
FIG. 3 is a simplified block diagram of the overload prevention lifting mechanism of the present invention;
fig. 4 is a graph of the folding arm luffing cylinder thrust P4 of fig. 3 as a function of the luffing angle γ.
The parts in the drawings are numbered as follows: 1. the device comprises a folding arm, 2, a telescopic arm, 3, a flying arm, 4, a working platform, 5, an upper triangular connecting piece, 6, a lower connecting rod of an upper arm of the folding arm, 7, an upper connecting rod of an upper arm of the folding arm, 8, a variable amplitude oil cylinder, 9, a connecting rod, 10, a lower triangular connecting piece, 11, an upper connecting rod of a lower arm of the folding arm, 12, a lower connecting rod of the lower arm of the folding arm, 13, a base, 14, an upper arm of the folding arm, 15, a lower arm of the folding arm, 16, an angle sensor, 17 and a pressure sensor.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1 to 2, an embodiment of the present invention includes: the utility model provides an overload prevention elevating system, its includes folding arm 1, flexible arm 2, fly arm and 3 work platform 4, flexible arm 2, fly arm 3 and work platform 4 are located folding arm 1 top, folding arm 1 includes folding arm upper arm 14 and folding arm underarm 15, be provided with on the folding arm underarm 15 and make folding arm upper arm 14 carry out the variable amplitude hydro-cylinder 8 that goes up and down, folding arm upper arm 14's one end is articulated with the one end of flexible arm 2, the other end of flexible arm 2 is articulated with the one end of fly arm 3, the other end of fly arm 3 is articulated with work platform 4, folding arm upper arm 14's the other end is articulated with the one end of folding arm underarm 15, the below of folding arm upper arm 14's one end and the articulated department of flexible arm 2's one end is provided with a fixed base 13, folding arm 15's the other end with base 13 is articulated.
Preferably, the upper folding arm 14 comprises an upper folding arm connecting rod 7 and a lower folding arm connecting rod 6, the lower folding arm 15 comprises an upper folding arm connecting rod 11 and a lower folding arm connecting rod 12, the upper folding arm connecting rod 7 and the lower folding arm connecting rod 6 are parallel to each other, the upper folding arm connecting rod 11 and the lower folding arm connecting rod 12 are parallel to each other, one end of the upper folding arm connecting rod 7 and one end of the lower folding arm connecting rod 6 are hinged to an upper triangular connecting piece 5, the other end of the upper folding arm connecting rod 7 and the other end of the lower folding arm connecting rod 6 are hinged to a lower triangular connecting piece 10, one end of the upper folding arm connecting rod 11 and one end of the lower folding arm connecting rod 12 are hinged to a lower triangular connecting piece 10, and the other end of the upper folding arm connecting rod 11 and the other end of the lower folding arm connecting rod 12 are hinged to a base 14 And the upper connecting rod 7 of the upper arm of the folding arm, the lower connecting rod 6 of the upper arm of the folding arm, the upper triangular connecting piece 5 and the lower triangular connecting piece 10 form a parallelogram connecting rod mechanism, and the upper connecting rod 11 of the lower arm of the folding arm, the lower connecting rod 12 of the lower arm of the folding arm, the lower triangular connecting piece 10 and the base 13 form a parallelogram connecting rod mechanism. The parallelogram linkage mechanism keeps the structural state of the parallelogram all the time in motion.
Preferably, a connecting line of a hinge point of the other end of the upper folding arm connecting rod 11 and the base 13 and a hinge point of the other end of the lower folding arm connecting rod 12 and the base 13 is located in the vertical direction. Namely, the connecting lines of two hinged points of the upper connecting rod 11 of the lower arm of the folding arm and the lower connecting rod 12 of the lower arm of the folding arm, which are respectively hinged with the base 13, are positioned in the vertical direction.
Preferably, a connecting line of a hinge point of one end of the upper arm upper link of the folding arm and the upper triangular connecting piece and a hinge point of one end of the lower link of the upper arm upper link of the folding arm and the upper triangular connecting piece is located in the vertical direction. In this way, the total force exerted on the upper arm 14 of the folding arm by each part above the upper arm 14 of the folding arm is always in the vertical direction, so that the thrust of the luffing cylinder 8 is only related to the weight of each part above the upper arm 14 of the folding arm, the weight of the upper arm 14 of the folding arm itself and the pitch angle thereof, and is not related to the luffing angle and the telescoping of each part above the upper arm 14 of the folding arm, including the telescopic arm 2, the fly jib 3 and the working platform 4. Under the condition that the weights of the folding arm upper arm 14, the telescopic arm 2, the flying arm 3 and the working platform 4 are constant, the thrust of the luffing cylinder 8 and the load of the working platform 4 have a certain corresponding relation.
Preferably, the lower end of the luffing cylinder 8 is hinged to the lower connecting rod 12 of the lower arm of the folding arm, the top end of the piston rod of the luffing cylinder 8 is hinged to the upper connecting rod 7 of the upper arm of the folding arm, and a pressure sensor 17 for detecting the working pressure of the luffing cylinder 8 is arranged in the luffing cylinder 8.
Preferably, a control unit (not shown) is further included, and the pressure sensor 17 is in communication connection with the control unit. The pressure sensor 17 detects the pressure of the luffing cylinder 8 and transmits the detection result to the control unit. The control unit judges whether the pressure of the luffing cylinder 8 exceeds a preset value.
Preferably, an angle sensor 16 for detecting the change of the pitch angle of the upper folding arm link 7 and the lower folding arm link 6 is further included, and the angle sensor 16 is connected with the control unit in a communication way. The angle sensor 16 may be mounted on the folding arm upper link 7 or the folding arm upper arm lower link 6. The angle sensor 16 detects the angle change of the upper arm of the folding arm, the control unit judges whether the working platform is overloaded, the angle of the upper arm of the folding arm and the pressure change of the oil cylinder are considered, and after the factors are calculated, the corresponding relation between the pressure of the luffing oil cylinder 8 and the load of the working platform is judged.
The overload prevention lifting mechanism of the invention can be calculated and analyzed as follows:
the total gravity of the self weights of the telescopic boom 2, the flying boom 3 and the working platform 4 is assumed to be G, and the virtual displacement thereof is deltaGThe hydraulic thrust of the luffing cylinder 8 of the folding arm 1 is P (P is the cylinder pressure X cylinder piston area), and the virtual displacement of the hydraulic thrust P of the luffing cylinder 8 of the folding arm is δPThey satisfy the following conditions according to the principle of virtual displacement:
G×δG+P×δP＝0。
the overload-proof lifting mechanism meeting the above conditions passes through G multiplied by deltaG+P×δPThe value of the hydraulic thrust P of the luffing cylinder 8 of the folding arm can be calculated as 0, and the value of P is only related to the weight of each arm support, the structural size of the folding arm and the luffing angle, but is not related to the structural size of the part above the folding arm, the luffing angle of the telescopic arm and the luffing angle of the flying arm. Therefore, the value of P is changed due to the structural weight change of the part above the folding arm, and the value of P can reach a larger value when the load of the working platform is overweight, the value exceeds a preset safety value, the overload of the working platform can be judged at the moment, and the load of the working platform is reduced to ensure the safety of the working platform. The specific process can be demonstrated in detail through the following steps:
for a stationary system, the condition to remain stationary is that the sum of all the work done by the active forces acting on the system on the virtual displacement of the point of action of the particle system is always zero. Assuming that the system has n particle systems, the mathematical expression can be expressed as:
in the formula:
the components of the main force acting on the ith mass point in the x direction, the y direction and the z direction respectively; delta Xi、δYi、δZiIs the virtual displacement of the ith particle in the x, y and z directions.
For the folding arm type self-walking aerial work platform of the overload prevention lifting mechanism, the total gravity of the rated load of a work platform 4 and the self weight of an arm support is G, and the virtual displacement is deltaGThe constraint release of the variable-amplitude oil cylinder 8 of the folding arm is replaced by hydraulic cylinder thrust P, and the virtual displacement of the hydraulic cylinder thrust P of the folding arm is set as deltaPApplying the virtual displacement principle to obtain:
G×δG+P×δp＝0 (2)
wherein the total weight G of the rated load of the working platform 4 and the dead weight of the arm support is a known quantity, and only the virtual displacement delta of the total weight of the rated load of the working platform 4 and the dead weight of the arm support is calculatedGAnd virtual displacement delta of folding arm hydraulic cylinderPThe thrust P of the folding arm hydraulic cylinder can be obtained according to the formula (2).
Firstly, the aerial work platform of the overload prevention lifting mechanism is simplified, and a mathematical model is established. A simplified model of an overload prevention elevator mechanism is shown in fig. 3.
Referring to fig. 3, a rectangular coordinate system is established by taking U as the origin of coordinates, R, U as the connection line as the y-axis, passing through the U point, and perpendicular to RU as the x-axis. O is1、O2Is an upper hinge point and a lower hinge point of a variable amplitude oil cylinder 8 of a folding arm, points A to Z are hinge points of a whole vehicle arm support, G1、G2、G3、G4、G5、G6Sequentially comprises a lower folding arm lower arm connecting rod 12 mass center, an upper folding arm lower arm connecting rod 11 mass center, a lower triangular connecting piece 10 mass center, a connecting rod 9 mass center, a lower folding arm upper arm connecting rod 6 mass center, an upper folding arm connecting rod 7 mass center, and G7Is the total mass center G of the upper triangular connecting piece 5, the telescopic arm 2, the fly arm 3 and the base 138Is the flying arm 3 centroid, G9Is the working platform 4 centroid.
Mixing O with1、O2、G1、G2、G3、G4、G5、G6、G7、G8And G9The coordinate expression of the point is expressed by the structural dimension parameter of the folding arm type self-walking aerial work platform, and the formula is as follows (3):
in the formula (3), gamma is the included angle between the upper arm lower connecting rod 6 of the folding arm and the horizontal plane, β and α are the included angles between the telescopic arm 2 and the fly arm 3 and the horizontal plane in sequence, and ha，gbAre respectively point O1、O2To lNQ、lRSThe vertical distances of the legs are P, Z respectively.
For G1～G9And differentiating the coordinate expression of the points to obtain the virtual displacement of the external load of each structure.
As can be seen from equation (4), the virtual displacement of the part above the folding boom is the same, which is only related to the structural size of the folding boom, and is not related to the structural size of the part above the folding boom, the boom luffing angle β, and the boom luffing angle α, and from equation (2), the thrust required by the folding boom hydraulic cylinder is not changed when the telescopic boom 2 and the boom 3 luff.
The method sequentially adopts a geometric method in the virtual displacement principle to solve the virtual displacement of the thrust of the folding arm hydraulic cylinder, and then obtains two groups of thrust expressions of the folding arm hydraulic cylinder.
Firstly, the length O of the hydraulic cylinder1O2Expressed, the expression is:
wherein:
the cylinder length change can be expressed as:
wherein:
substituting the following formulae (5), (6) and (7) into formula (8):
to simplify equation (9), take:
C2＝((lYZ-lQP)·cosγ-(ha-hb)·sinγ)·(-(lYZ-lQP)·sinγ+(-ha+hb)·cosγ)
C3＝((lYZ+lQP)·sinγ+(-ha+hb)·cosγ+lQY)·(-(-ha+hb)·sinγ+(lYZ+lQP)·cosγ)
the following can be obtained:
according to the formula (2), the following formula can be obtained by using a virtual displacement principle for the folding arm type self-walking aerial work platform:
in the formula: g1～g8The rated load of the working platform 4 and the dead weights of the working platform 4, the working platform rotor (not marked in the figure), the upper and lower fly jib connecting rods (not marked in the figure), the fly jib base (not marked in the figure), the telescopic boom 2 and the upper triangular connecting piece 5 are sequentially arranged, namely the weights of all structures above the folding boom; g9～g14The dead weight of an upper arm upper connecting rod 7, a lower arm upper connecting rod 6, a lower arm upper connecting rod 11, a lower arm lower connecting rod 12, a lower triangular connecting piece 10 and a connecting rod 9 of the folding arm are sequentially arranged; p4The thrust of the hydraulic cylinder.
To simplify equation (4), take:
C6＝lUV·cosγ
C10＝2(lUV·cosγ)
the following can be obtained:
then general formula (10)And (12) the thrust P of the hydraulic cylinder can be obtained by substituting the formula (11)4The calculation expression is as follows:
values of all structural parameters of the folding arm and the like are shown in the table 1, the geometric parameters in the table 1 are substituted into a thrust expression of the hydraulic cylinder of the folding arm for calculation, the calculated values are finally substituted into a formula (13), and MATLAB is used for drawing the thrust P of the variable-amplitude hydraulic cylinder of the folding arm4The curve of the variation with the argument gamma is shown in fig. 4.
Table 1: structural dimension (mm) of folding arm, structural angle (DEG) and weight value (N) of folding arm
Table 1 Structure dimensions(mm)，structural angle(°)and gravity value(N)of folding arm
As can be seen from fig. 4, when the amplitude angle of the hydraulic cylinder is 0 °, the required thrust is maximum, which is 98339N.
The following conclusions can be drawn from the formulae (4), (12), (13):
the thrust P required by the luffing cylinder 8 of the folding arm is related to the weight of each arm support, the structural size and the luffing angle of the folding arm, and is unrelated to the structural size of the parts above the folding arm, the luffing angle β of the telescopic arm, the luffing angle α of the flying arm and the corner or elevation position of the working platform 4.
Therefore, the corresponding relation between the P value and the load of the working platform 4 can be obtained, when the P value is larger than the set value, the load of the working platform 4 is larger than the set value, the working platform 4 is in an overload state, and the load of the working platform 4 needs to be reduced, so that the safety of the working platform 4 is ensured.
The invention also provides a control method for the overload prevention lifting mechanism, which comprises the following steps:
(1) the pressure sensor detects the pressure value of the amplitude variation oil cylinder for pushing the upper arm of the folding arm and transmits a signal to the control unit of the lifting mechanism;
(2) the angle sensor detects the angle position of the lower arm or the upper arm of the folding arm and transmits the signal to the control unit of the lifting mechanism
(3) The control unit judges whether the pressure value of the luffing cylinder and the angle position of the folding arm exceed a preset value or not through the detected pressure value of the luffing cylinder and the detected angle position of the folding arm, if the pressure value exceeds the preset value, the load of the working platform in the lifting mechanism exceeds a set value, the working platform is in an overload state and limits the action of the working platform, and at the moment, the load of the working platform is reduced.
Because the thrust value of the variable amplitude oil cylinder is only related to the self weight and angle change of the folding arm and the weight of the part above the folding arm and is unrelated to the variable amplitude angle or the extension of the part above the folding arm, the thrust value of the variable amplitude oil cylinder is in corresponding relation to the weight of the part above the folding arm, the self weight of the folding arm is certain, and the self angle change of the folding arm can be detected and calculated through the angle sensor. Under the condition that the weights of the telescopic arm, the fly arm and the working platform are fixed, the change of the load of the working platform is related. The thrust value of the variable-amplitude oil cylinder can be displayed through the control unit and the display device, if the thrust value of the variable-amplitude oil cylinder exceeds a preset value, the situation that the load of the working platform exceeds a set value is also shown, the working platform is in an overload state, and the load of the working platform is reduced at the moment, including the reduction of the number of workers on the working platform and the weight of a carried object, so that the working safety is ensured.
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by the present specification, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (8)
1. The utility model provides an overload prevention elevating system, includes folding arm, flexible arm, fly jib and work platform are located folding arm top, folding arm includes folding arm upper arm and folding arm underarm, be provided with the variable amplitude hydro-cylinder that makes folding arm upper arm go up and down on the folding arm underarm, the one end of folding arm upper arm is articulated with the one end of flexible arm, the other end of flexible arm is articulated with the one end of fly jib, the other end of fly jib is articulated with work platform, the other end of folding arm upper arm is articulated with the one end of folding arm underarm, its characterized in that, the one end of folding arm upper arm is provided with a fixed base with the below of the articulated department of the one end of flexible arm, the other end of folding arm underarm with the base is articulated. .
2. The overload lifting mechanism according to claim 1, wherein the upper folding arm includes an upper folding arm connecting rod and a lower folding arm connecting rod, the lower folding arm includes an upper folding arm connecting rod and a lower folding arm connecting rod, the upper folding arm connecting rod and the lower folding arm connecting rod are parallel to each other, one end of the upper folding arm connecting rod and one end of the lower folding arm connecting rod are respectively hinged to an upper triangular connecting member, the other end of the upper folding arm connecting rod and the other end of the lower folding arm connecting rod are respectively hinged to a lower triangular connecting member, one end of the upper folding arm connecting rod and one end of the lower folding arm connecting rod are respectively hinged to a lower triangular connecting member, and the other end of the upper folding arm connecting rod and the other end of the lower folding arm connecting rod are respectively hinged to the base And the upper connecting rod of the upper arm of the folding arm, the lower connecting rod of the lower arm of the folding arm, the upper triangular connecting piece and the lower triangular connecting piece form a parallelogram connecting rod mechanism, and the upper connecting rod of the lower arm of the folding arm, the lower triangular connecting piece and the base form a parallelogram connecting rod mechanism.
3. The overload prevention lifting mechanism according to claim 2, wherein a connecting line between a hinge point of the other end of the upper connecting rod of the lower arm of the folding arm and the base and a hinge point of the other end of the lower connecting rod of the lower arm of the folding arm and the base is in an up-down vertical direction.
4. The overload prevention lifting mechanism according to claim 3, wherein a connecting line between a hinge point of the upper link of the upper arm of the folding arm and the upper triangular connecting piece and a hinge point of the lower link of the upper arm of the folding arm and the upper triangular connecting piece is in an up-down vertical direction.
5. The overload prevention lifting mechanism as recited in claim 3, wherein the lower end of the luffing cylinder is hinged to a lower connecting rod of a lower arm of the folding arm, the top end of a piston rod of the luffing cylinder is hinged to an upper connecting rod of an upper arm of the folding arm, and a pressure sensor for detecting the pressure of the luffing cylinder is arranged in the luffing cylinder.
6. The overload lift mechanism of claim 5, further comprising a control unit, wherein the pressure sensor is in communication with the control unit.
7. The overload lift mechanism of claim 6, further comprising angle sensors for detecting the pitch angles of the upper and lower links of the upper arm of the folding arm, the angle sensors being communicatively coupled to the control unit.
8. A control method for use in an overload prevention lifting mechanism according to any one of claims 1 to 7, characterised by the steps of:
(1) the pressure sensor detects the pressure value of the amplitude variation oil cylinder for pushing the upper arm of the folding arm and transmits a signal to the control unit of the lifting mechanism;
(2) the angle sensor detects the angle position of the lower arm or the upper arm of the folding arm and transmits the signal to the control unit of the lifting mechanism
(3) The control unit judges whether the pressure value of the luffing cylinder and the angle position of the folding arm exceed a preset value or not through the detected pressure value of the luffing cylinder and the detected angle position of the folding arm, if the pressure value exceeds the preset value, the load of the working platform in the lifting mechanism exceeds a set value, the working platform is in an overload state and limits the action of the working platform, and at the moment, the load of the working platform is reduced.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2019110270743 | 2019-10-28 | ||
| CN201911027074.3A CN110642198A (en) | 2019-10-28 | 2019-10-28 | Overload-prevention lifting mechanism and control method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110885046A true CN110885046A (en) | 2020-03-17 |
Family
ID=69013567
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911027074.3A Pending CN110642198A (en) | 2019-10-28 | 2019-10-28 | Overload-prevention lifting mechanism and control method thereof |
| CN201911371581.9A Pending CN110885046A (en) | 2019-10-28 | 2019-12-27 | Overload-prevention lifting mechanism and control method thereof |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911027074.3A Pending CN110642198A (en) | 2019-10-28 | 2019-10-28 | Overload-prevention lifting mechanism and control method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (2) | CN110642198A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114314416A (en) * | 2022-01-13 | 2022-04-12 | 广州市岳中数字科技有限公司 | Double-layer connecting rod lifting machine |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111086961A (en) * | 2020-01-19 | 2020-05-01 | 浙江鼎力机械股份有限公司 | Crank arm lifting structure of crank arm type aerial work platform truck |
| CN112827285B (en) * | 2020-12-24 | 2023-07-28 | 福龙马集团股份有限公司 | High-altitude spray arm support system of dust suppression equipment and lifting control method thereof |
| CN112723268A (en) * | 2020-12-28 | 2021-04-30 | 湖南中联重科智能高空作业机械有限公司 | High-altitude operation machine load and overload determining method and device and high-altitude operation machine |
Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105021086A (en) * | 2015-08-05 | 2015-11-04 | 沈阳仪表科学研究院有限公司 | Vehicle-mounted type cleaning device |
| CN204981051U (en) * | 2015-08-17 | 2016-01-20 | 徐州重型机械有限公司 | Structure of weighing and use this structure from walking aerial working platform |
| CN105347274A (en) * | 2015-12-11 | 2016-02-24 | 湖南星邦重工有限公司 | Aerial work platform |
| CN205676107U (en) * | 2016-06-15 | 2016-11-09 | 国网重庆市电力公司电力科学研究院 | A kind of robot for high-voltage hot-line work and upper assembling device thereof |
| CN106430020A (en) * | 2016-09-14 | 2017-02-22 | 浙江鼎力机械股份有限公司 | Overload protection device and system and aerial work platform |
| CN106629523A (en) * | 2016-10-25 | 2017-05-10 | 徐州海伦哲专用车辆股份有限公司 | Aerial work vehicle with self-stabilizing system and self-stabilizing control method thereof |
| CN106698279A (en) * | 2015-03-27 | 2017-05-24 | 江苏省电力公司常州供电公司 | Amplitude limiting system for insulated aerial work platform |
| CN107226431A (en) * | 2016-03-25 | 2017-10-03 | 新乡市华航航空液压设备有限公司 | A kind of folding-jib hydraulic elevating platform |
| CN206966279U (en) * | 2017-07-03 | 2018-02-06 | 辽宁天信专用汽车制造有限公司 | The double leval jib elevating mechanism of on-vehicle lens cleaning machine |
| CN107715347A (en) * | 2017-09-15 | 2018-02-23 | 湖北华舟重工应急装备股份有限公司 | A kind of folding-jib high level Quick rescue car |
| CN107986206A (en) * | 2017-12-28 | 2018-05-04 | 徐州海伦哲专用车辆股份有限公司 | A kind of mixing arm type high-altitude operation vehicle of multifreedom motion |
| CN109553040A (en) * | 2018-11-30 | 2019-04-02 | 徐工消防安全装备有限公司 | Aerial working platform vehicle and aerial working platform vehicle load capacity detection method |
| CN109748216A (en) * | 2019-03-19 | 2019-05-14 | 威海怡和专用设备制造有限公司 | Vehicle-mounted hydraulic elevating mechanism |
| US20190194007A1 (en) * | 2017-12-22 | 2019-06-27 | Altec Industries, Inc. | Boom load monitoring |
| CN212101903U (en) * | 2019-10-28 | 2020-12-08 | 江苏东迈重工机械有限公司 | Anti-overload lifting mechanism |
-
2019
- 2019-10-28 CN CN201911027074.3A patent/CN110642198A/en active Pending
- 2019-12-27 CN CN201911371581.9A patent/CN110885046A/en active Pending
Patent Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106698279A (en) * | 2015-03-27 | 2017-05-24 | 江苏省电力公司常州供电公司 | Amplitude limiting system for insulated aerial work platform |
| CN105021086A (en) * | 2015-08-05 | 2015-11-04 | 沈阳仪表科学研究院有限公司 | Vehicle-mounted type cleaning device |
| CN204981051U (en) * | 2015-08-17 | 2016-01-20 | 徐州重型机械有限公司 | Structure of weighing and use this structure from walking aerial working platform |
| CN105347274A (en) * | 2015-12-11 | 2016-02-24 | 湖南星邦重工有限公司 | Aerial work platform |
| CN107226431A (en) * | 2016-03-25 | 2017-10-03 | 新乡市华航航空液压设备有限公司 | A kind of folding-jib hydraulic elevating platform |
| CN205676107U (en) * | 2016-06-15 | 2016-11-09 | 国网重庆市电力公司电力科学研究院 | A kind of robot for high-voltage hot-line work and upper assembling device thereof |
| CN106430020A (en) * | 2016-09-14 | 2017-02-22 | 浙江鼎力机械股份有限公司 | Overload protection device and system and aerial work platform |
| CN106629523A (en) * | 2016-10-25 | 2017-05-10 | 徐州海伦哲专用车辆股份有限公司 | Aerial work vehicle with self-stabilizing system and self-stabilizing control method thereof |
| CN206966279U (en) * | 2017-07-03 | 2018-02-06 | 辽宁天信专用汽车制造有限公司 | The double leval jib elevating mechanism of on-vehicle lens cleaning machine |
| CN107715347A (en) * | 2017-09-15 | 2018-02-23 | 湖北华舟重工应急装备股份有限公司 | A kind of folding-jib high level Quick rescue car |
| US20190194007A1 (en) * | 2017-12-22 | 2019-06-27 | Altec Industries, Inc. | Boom load monitoring |
| CN107986206A (en) * | 2017-12-28 | 2018-05-04 | 徐州海伦哲专用车辆股份有限公司 | A kind of mixing arm type high-altitude operation vehicle of multifreedom motion |
| CN109553040A (en) * | 2018-11-30 | 2019-04-02 | 徐工消防安全装备有限公司 | Aerial working platform vehicle and aerial working platform vehicle load capacity detection method |
| CN109748216A (en) * | 2019-03-19 | 2019-05-14 | 威海怡和专用设备制造有限公司 | Vehicle-mounted hydraulic elevating mechanism |
| CN212101903U (en) * | 2019-10-28 | 2020-12-08 | 江苏东迈重工机械有限公司 | Anti-overload lifting mechanism |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114314416A (en) * | 2022-01-13 | 2022-04-12 | 广州市岳中数字科技有限公司 | Double-layer connecting rod lifting machine |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110642198A (en) | 2020-01-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110885046A (en) | Overload-prevention lifting mechanism and control method thereof | |
| WO2005094296A2 (en) | Hydraulic auxiliary hoist and crane control for high precision load positioning | |
| CN205616444U (en) | Examine type electric block lifting hook in initiative | |
| CN102774757B (en) | Engineering machinery | |
| CN111217298A (en) | Automatic attitude adjusting device and method based on intelligent sensor digital hydraulic cylinder | |
| CN104326356A (en) | Construction platform hanger with clear stress and adjustable hanging point | |
| CN111056439A (en) | Crane anti-swing method based on machine vision | |
| CN212101903U (en) | Anti-overload lifting mechanism | |
| CN201785176U (en) | High-altitude operation device and leveling mechanism and high-altitude operation car of high-altitude operation device | |
| CN204848013U (en) | Liftable tower crane | |
| CN110885042B (en) | Arm support equipment, control method and control device thereof, and computer-readable storage medium | |
| CN108675165A (en) | It is peculiar to vessel subtract to shake crane and subtract shake control method | |
| TWM605945U (en) | Mobile crane with anti-overturn monitoring function and anti-overturn monitoring device thereof | |
| CN204661180U (en) | A kind of tower crane | |
| CN207060415U (en) | UAS for the monitoring of building site high-altitude | |
| CN216007754U (en) | All-steel attached lifting scaffold | |
| CN211647241U (en) | Attached lifting scaffold early warning control system | |
| CN210595161U (en) | Safety protection system for aerial work equipment | |
| CN208182519U (en) | A kind of machinery maintenance device | |
| CN212532037U (en) | Lifting appliance anti-shaking structure of bridge crane | |
| CN204281029U (en) | A kind of stressed clear and definite and adjustable operation platform suspender of suspension centre | |
| CN211971573U (en) | Double-arm tower crane | |
| CN210798243U (en) | Building construction is with lift that has safeguard function | |
| CN209352390U (en) | A kind of building hoist safety monitoring system gravity alarm breaker device | |
| CN209906188U (en) | Lifting appliance |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |