CN117945280B

CN117945280B - Automatic leveling OHT lifting device and lifting method of overhead travelling crane carrying system

Info

Publication number: CN117945280B
Application number: CN202410346527.3A
Authority: CN
Inventors: 刘越; 李在朋; 滕焕云; 柳宇涛; 蒲宗杰; 小野出; 赵萌
Original assignee: Zunxin Intelligent Technology Suzhou Co ltd
Current assignee: Zunxin Intelligent Technology Suzhou Co ltd
Priority date: 2024-03-26
Filing date: 2024-03-26
Publication date: 2024-06-04
Anticipated expiration: 2044-03-26
Also published as: CN117945280A

Abstract

The invention relates to the technical field of overhead travelling crane carrying, and provides an automatic leveling OHT lifting device of an overhead travelling crane carrying system, which comprises: the device comprises a top fixing structure, a lifting structure, at least three flexible synchronous transmission structures and a control structure; the flexible synchronous transmission structures are configured to simultaneously receive pulse signals sent by the control structures, the sagging lengths of the flexible synchronous transmission structures are fed back to the control structures in real time, the control structures calculate the sagging length limit deviations of all the flexible synchronous transmission structures, and when the limit deviations exceed the preset range, the control structures adjust the frequency of the pulse signals sent to the flexible synchronous transmission structures influencing the calculation results of the limit deviations so as to automatically adjust the sagging lengths of the flexible synchronous transmission structures in real time. The problem of unstable swinging caused by lack of stable structural support in the lifting process is solved.

Description

Automatic leveling OHT lifting device and lifting method of overhead travelling crane carrying system

Technical Field

The invention relates to the technical field of overhead travelling crane carrying, in particular to an automatic leveling OHT lifting device and lifting method of an overhead travelling crane carrying system.

Background

With the continuous deep development of semiconductor technology in China, system integrators are required to continuously improve the production efficiency and reduce the cost to adapt to the development of the technology. Crown block handling systems (OHT, overhead Hoist Transporter) are an important automated handling system in semiconductor manufacturing facilities, which generally include a crown block equipped with a lifting device (e.g., a motorized hook) that moves along a track suspended from a ceiling, and are widely used in industry, manufacturing, and warehousing. The material conveying efficiency can be improved, the labor cost can be reduced, the space occupation rate of workshops can be reduced, and the pollution rate of products can be correspondingly reduced, so that the whole production flow can be fundamentally improved. At present, the wafer dot-to-dot transport is realized by using OHT trolleys, but an OHT lifting system is required for safely lifting so many trolleys into a crown block track.

The lifting structure adopted by the current enterprises generally takes aluminum alloy profiles as a structural frame, metal sheet metal parts as connecting pieces, vertical guide rails as guiding mechanisms of the lifting structure, driving mechanisms drive chains as lifting power, and a lifting machine is driven to lift along the guide rails. The mechanism has the advantages that the mechanism is firm and stable, the linear guide rail can bear radial impact force, but the defect is obvious, the structural redundancy of the mechanism consumes a large amount of design production and installation cost, occupies space to reduce the utilization rate of workshops, and the mechanism is gradually eliminated by the development requirement of workshops with high utilization rate.

In addition, there is also the mode that the enterprise utilized the belt hoist at present to promote the OHT dolly, with ground fixed establishment all cancellation, places driving motor at the roof, and a driving motor control a plurality of hoist wheels, the hoist wheel stretches out four belts and fixes respectively at four angles of lifting machine, and motor rotation control belt drives the lifting machine and slowly rises, but finds in the in-service use and carries the lifting machine swing of OHT dolly serious, and the OHT dolly can't be fixed, causes serious security risk. There are two analytical reasons, one is that the OHT trolley is not completely symmetrical, resulting in uneven stress on the elevator itself. The elevator is pulled by the four belts and has no other fixing mechanism, so that the elevator can swing once being stressed unevenly. On the other hand, in the lifting process of the lifting machine, three of the four belts can be used for determining a plane and bearing most of load, and the other belt is smaller in stress, so that the four belts are different in tension, the difference of the lengths of the four belts is further increased in the uniform-speed lifting process of the top winch wheel, and the lifting machine is caused to swing due to uneven stress.

Disclosure of Invention

In view of the above problems, the present invention aims to provide an automatic leveling OHT lifting device and lifting method for an overhead travelling crane handling system, so as to solve the problem of unstable swing caused by lack of stable structural support in the lifting process.

The above object of the present invention is achieved by the following technical solutions:

An auto-leveling OHT lift device of an overhead travelling crane handling system for raising or lowering an OHT trolley of the overhead travelling crane handling system to a workstation or storage area adapted to different heights when carrying a material using the OHT trolley, the OHT lift device comprising: the device comprises a top fixing structure, a lifting structure, at least three flexible synchronous transmission structures and a control structure;

The lower part of the top fixing structure is connected with the upper parts of at least three flexible synchronous transmission structures, the upper surface of the lifting structure is connected with the lower parts of at least three flexible synchronous transmission structures, the center point of a graph formed by connecting points of the at least three flexible synchronous transmission structures on the lifting structure is the center point of gravity of the lifting structure, and the control structure is electrically connected with the at least three flexible synchronous transmission structures;

The flexible synchronous transmission structures are configured to simultaneously receive pulse signals sent by the control structures, and feed the sagging lengths of the flexible synchronous transmission structures back to the control structures in real time, the control structures calculate the sagging length limit deviations of all the flexible synchronous transmission structures, when the limit deviations exceed a preset range, the control structures adjust the frequency of the pulse signals sent to the flexible synchronous transmission structures influencing the calculation results of the limit deviations so as to automatically adjust the sagging lengths of the flexible synchronous transmission structures in real time, the limit deviations of the sagging lengths of all the flexible synchronous transmission structures in the process of motion control are in the preset range, automatic leveling of the lifting structures is achieved when the lifting structures are adopted to lift or descend the OHT trolley, after leveling, the lifting structures form stable and non-swinging lifting platforms, and the OHT trolley stably lifts or descends to a work station or a storage area with the aid of the lifting platforms so as to carry materials.

Further, the automatic leveling OHT lifting device of the overhead travelling crane handling system further comprises: a plurality of ranging structures which are in one-to-one correspondence with the flexible synchronous transmission structures;

the distance measuring structures are arranged close to the flexible synchronous transmission structures in a one-to-one correspondence manner, and are configured to measure the sagging length of the flexible synchronous transmission structures when the lifting structures perform motion control, and record and transmit the sagging length to a controller in the control structure in real time;

The distance measuring structure adopts a structure comprising a laser distance measuring instrument or a microwave distance measuring instrument.

Further, the controller is configured to calculate the sagging lengths of all the received flexible synchronous transmission structures, calculate the limit deviation of the sagging lengths, and select to automatically adjust the sagging lengths of the flexible synchronous transmission structures, which affect the calculation result of the limit deviation, in real time when the limit deviation exceeds the preset range, so as to adjust the limit deviation within the preset range;

wherein the limit deviation = length maximum-length minimum, the real-time automatic adjustment of the sag length of the flexible synchronous drive is configured to adjust the sag length in real-time by adjusting the speed of ascent or descent of the lifting structure.

Further, the ranging structure is configured to acquire the sagging lengths of all the flexible synchronous transmission structures by timing synchronous detection of the distance from the ranging structure to a detection point on the lifting structure corresponding to the current flexible synchronous transmission structure;

calculating deviation data of the sagging length of the other flexible synchronous transmission structures and the reference length by taking the sagging length of one flexible synchronous transmission structure as the reference length;

And converting the deviation data into a rotation angle instruction required by a driving piece, and sending the rotation instruction to the driving piece by the driver to position, so that the OHT crown block can stably lift.

Further, the drivers are configured to be provided with corresponding software, in which a simulation curve of the running speed and the acceleration simulated according to data is preset, and when the lifting structure moves up and down, the current use state of each driver is judged according to the derivative of the distance change rate of the read sagging length and the use state of each driver is compared with the simulation curve to be adjusted;

simultaneously, the rotation angular speed of the driving piece is finely adjusted in real time, so that all the driving pieces are in a balanced state.

Further, any one of the flexible synchronous transmission structures specifically includes: the driving piece, the winding piece and the flexible conveying belt;

The driving piece is arranged below the top fixing structure and controls the winch piece to rotate, wherein the driving piece adopts a structure comprising a servo motor or an asynchronous motor, and the driving piece adopts a structure comprising a rotating shaft control, a ball screw and a gear rack to drive the winch piece to rotate;

One end of the flexible conveying belt is clamped in the hoisting piece, the other end of the flexible conveying belt is fixedly connected with the lifting structure below, the sagging length of the flexible conveying belt is adjusted by rotating the hoisting piece, so that the lifting structure is controlled to ascend or descend, and the flexible conveying belt comprises a structure including a belt, a synchronous belt and a chain.

Further, the driving member further includes:

The driving piece is configured to receive a pulse signal sent by the driver in the control structure, control the rotating speed of the driving piece according to the frequency of the pulse signal, and rotate a preset fixed angle according to a preset direction when the driving piece receives a pulse signal sent by the driver, wherein the preset fixed angle is a preset step angle of the driving piece;

The driving piece is configured to control the angular displacement of the driving piece by controlling the number of the pulse signals received in unit time so as to control the rotating speed of the driving piece;

The speed of the flexible conveyor belt rising or falling, that is, the speed of the lifting structure rising or falling is v1=v2×d×pi, where v1 is the speed of the lifting structure rising or falling, v2 is the rotation speed of the driving member, r/s is the diameter of the winding portion of the flexible conveyor belt of the winding member, and m is the circumferential rate.

Further, the winding part specifically includes: the wheel core, the pressing plate bolt, the conveyor belt outlet area and the winding hub;

The center of the wheel core is provided with a rotating shaft mounting hole for mounting a rotating shaft, the rotating shaft mounting hole is provided with a bulge for clamping the rotating shaft, the surface of the wheel core corresponding to the bulge is of a trapezoid bulge structure, and the other side of the wheel core is of a plane structure;

One end of the flexible conveying belt is wound on the wheel core, a threaded hole is formed in the parallel surface of the plane structure of the wheel core and the pressing plate, and a conveying belt hole corresponding to the threaded hole is formed in the flexible conveying belt;

The pressing plate bolt is configured to pass through the pressing plate and the conveying belt hole and is screwed in the threaded hole of the wheel core, so that the flexible conveying belt and the wheel core are tightly locked;

the conveyor belt exit region is configured to draw the flexible conveyor belt from the region where the wheel core is located to wind on the winding hub disposed on the wheel core outer race.

Further, the automatic leveling OHT lifting device of the overhead travelling crane handling system further comprises: a first lifting structure identification unit and a second lifting structure identification unit;

the first lifting structure identification unit is arranged at a position where the lifting structure is required to be decelerated, and the second lifting structure identification unit is arranged at a position where the lifting structure is required to be immediately stopped;

The lifting structure is configured to start accelerating operation at a first acceleration rate when starting the motion control, to start operating at a constant speed at a first preset operating speed when accelerating to the first preset operating speed, to start decelerating operation at a second acceleration rate when the lifting structure is operated to a position where the first lifting structure identifying unit is located, to start operating at a constant speed at a second preset operating speed when decelerating to the second preset operating speed, and to stop operating the lifting structure immediately when the lifting structure is operated to a position where the second lifting structure identifying unit is located.

Further, the top fixing structure specifically includes: roof connecting piece, several leveling pieces and transmission structure installing piece;

The roof connecting piece is connected with a roof;

The transmission structure mounting piece is connected with at least three flexible synchronous transmission structures and is used for mounting and fixing at least three flexible synchronous transmission structures;

The upper parts of the leveling pieces are connected with the roof connecting pieces, and the lower parts of the leveling pieces are connected with the transmission structure mounting pieces and used for leveling the transmission structure mounting pieces.

The roof connecting piece comprises a roof steel plate and a plurality of roof profiles, wherein the roof steel plate is horizontally arranged on a roof, and the roof profiles are vertically arranged on the roof steel plate;

the leveling piece adopts a structure comprising a leveling bolt, a leveling screw and a leveling pin;

The transmission structure mounting piece comprises a connecting unit, a profile frame and a mounting bottom plate, wherein the connecting unit is used for fixing the profile frame and the mounting bottom plate, and is connected with the leveling piece, the profile frame is arranged above the mounting bottom plate in parallel, and the mounting bottom plate is used for mounting and fixing at least three flexible synchronous transmission structures.

Further, the roof profile comprises a profile upper side opening, a profile lower side opening, a hollow connecting part and a profile jacket;

The upper side opening of the section bar is connected with the roof steel plate through bolts, the lower side opening of the section bar is connected with the leveling piece, and the hollow connecting part is connected with the upper side opening of the section bar and the lower side opening of the section bar;

the profile jacket is sleeved outside the whole body formed by the upper side opening of the profile, the hollow connecting part and the lower side opening of the profile and is used for reinforcing the whole structure of the roof profile.

Further, the leveling piece comprises an adjusting bolt, an adjusting nut and a leveling support;

The upper part of the adjusting bolt is provided with a first right-handed thread structure, the lower part of the adjusting bolt is provided with a first left-handed thread structure, the first right-handed thread structure is connected with the roof profile, and the first left-handed thread structure is connected with the adjusting nut;

the upper part of the adjusting nut is provided with a second left-handed thread structure, the lower part of the adjusting nut is provided with a second right-handed thread structure, and the second left-handed thread structure is connected with the first left-handed thread structure;

The upper part of the leveling support is a third right-handed thread structure, the lower part of the leveling support is an embedded structure which is fixedly connected with the connecting unit, and the third right-handed thread structure is connected with the second right-handed thread structure;

When the adjusting nut is rotated clockwise, the adjusting bolt moves downwards relative to the adjusting nut under the driving of the adjusting nut, the leveling support moves upwards relative to the adjusting nut, the distance between the roof connecting piece and the transmission structure mounting piece is shortened, and the height of the transmission structure mounting piece is increased;

When the adjusting nut rotates anticlockwise, the adjusting bolt moves upwards relative to the adjusting nut under the driving of the adjusting nut, the leveling support moves downwards relative to the adjusting nut, the distance between the roof connecting piece and the transmission structure mounting piece is prolonged, and the height of the transmission structure mounting piece is reduced.

Further, the connection unit comprises a riser, a cross plate, a first right triangle stiffener and a second right triangle stiffener;

the vertical plate is used for fixing the section frame and the mounting bottom plate, and the section frame and the mounting bottom plate are arranged at the top end of one surface of the vertical plate;

The transverse plate is vertically arranged at the bottom end of the other surface of the vertical plate, and the upper surface of the transverse plate is connected with the leveling piece;

The first right triangle reinforcement and the second right triangle are arranged on two sides of the vertical plate and the transverse plate, and two sides of the first right triangle reinforcement and the second right triangle reinforcement, which are perpendicular to each other, are respectively fixedly connected with the vertical plate and the transverse plate.

Further, the automatic leveling OHT lifting device of the overhead travelling crane handling system further comprises: the plurality of fracture detection mechanisms are in one-to-one correspondence with the flexible synchronous transmission structures;

Any fracture detection mechanism comprises a fixed seat, a wane, a spring supporting structure, a tensioning wheel and a travel switch respectively;

The fixing seat is arranged on the lifting structure through a bolt, the middle position of the rocker is rotatably connected with the middle position of the fixing seat, and the rocker realizes rocker movement by taking the middle position as a fixed point;

The upper end of the spring supporting structure is a fixed end, the lower end of the spring supporting structure is a movable end, the tensioning wheel is arranged at the front end of the rocker, and the movable end of the spring supporting structure is fixed at one side of the rear end of the rocker;

the rear end of the rocker is pulled up by the spring supporting structure, and the tensioning wheel at the front end presses the flexible conveyor belt downwards to realize the function of tensioning the flexible conveyor belt;

The travel switch runner of travel switch set up in the rear end of wane with the opposite side of spring bearing structure, when the pulling force of flexible conveyer belt is in first default scope the distance scope of wane rear end perk is in the second default scope, travel switch runner is in at this moment on the wane rear end contact surface, travel switch is in under the pressure effect of travel switch runner the off-state, otherwise when the distance scope of wane rear end perk is not in the second default scope, travel switch runner breaks away from wane rear end contact surface, travel switch is because travel switch runner does not receive pressure and is opened, it is considered that flexible conveyer belt breaks this moment.

Further, the spring support structure includes: the device comprises a spring, an upper spring supporting pin, a lower spring supporting pin and a stand column seat;

The upright post seat is arranged on the lifting structure through a bolt, the upper spring supporting pin is fixedly connected with the upper end of the upright post seat, the upper end of the spring is used as the fixed end and is fixedly connected with the upper spring supporting pin, and the lower end of the spring is used as the movable end and is fixedly connected with the lower spring supporting pin;

The lower spring supporting pin is connected with one side of the rear end of the rocker.

Further, the travel switch includes: the travel switch rotating wheel, the travel switch contact and the travel switch bracket are arranged on the travel switch rotating wheel;

The travel switch support is fixed on the lifting structure, and the travel switch contact point is fixed on one side, close to the rocker, of the travel switch support;

The front end of the travel switch contact is provided with the travel switch rotating wheel, and the travel switch rotating wheel slides on the contact surface of the rocker and the travel switch.

A crown block handling system comprising: the automatic leveling OHT lifting device and the OHT trolley of the overhead travelling crane conveying system;

The OHT trolley is used for ascending or descending to work stations or storage areas which are suitable for different heights to carry materials when the materials are required to be carried;

the OHT lift is used to raise or lower the OHT vehicle stably and without rocking to move the OHT vehicle to a workstation or storage area adapted to the current elevation.

The lifting method of the automatic leveling OHT lifting device based on the overhead travelling crane conveying system comprises the following steps of:

S1: placing the OHT trolley in the middle position of a lifting structure, and simultaneously issuing a starting instruction to at least three flexible synchronous transmission structures by a controller, wherein the at least three flexible synchronous transmission structures simultaneously control the lifting structure to ascend or descend and drive the lifting structure to ascend or descend;

S2: and measuring the sagging lengths of all the flexible synchronous transmission structures in the motion control process in real time, and when any one or more numerical values of the sagging lengths are found to cause the limit deviation to exceed a preset range, selecting the sagging length of the flexible synchronous transmission structure influencing the calculation result of the limit deviation to automatically adjust in real time so as to adjust the limit deviation to be within the preset range.

Compared with the prior art, the invention has at least one of the following beneficial effects:

(1) By providing an auto leveling OHT lift device for an overhead travelling crane handling system, comprising: the overhead fixing structure, the lifting structure, the at least three flexible synchronous transmission structures, the control structure and the fixing structure of the traditional hoist are eliminated, the OHT trolley is lifted only by utilizing the mode that the at least three flexible synchronous transmission structures move and hoist from top to bottom, the production and manufacturing cost is greatly saved, the using area of a factory is optimized, and the environment of the factory is beautified.

(2) Through setting up an independent driving piece to every flexible synchronous transmission structure, when flexible synchronous transmission structure's sagging length changed, can the pertinence adjust to guarantee that every flexible synchronous transmission structure's sagging length always.

(3) The distance measuring structures corresponding to each flexible synchronous transmission structure are arranged, so that the sagging length of each flexible synchronous transmission structure can be recorded in real time, and the rotating speed of each driving piece is controlled by a controller such as a PLC to achieve the purpose of controlling the sagging length of each flexible synchronous transmission structure, and the whole process is automatically controlled according to a program without manual work. Meanwhile, if the automatic control is canceled due to the cost problem and the manual adjustment is changed, the adjustment mode of the invention is still applicable.

(4) The biggest problem of flexible synchronous transmission structure is the unstable problem of swaying that lacks stable structural support in the promotion process, and especially in the semiconductor trade, the wafer price of transport is higher, and is very high to the security requirement of transportation. The invention thoroughly solves the problem of unstable swing of the flexible lifting structure, can be applied to the semiconductor industry, can be applied to article carrying projects between any factory sites, and ensures the safety of transported products.

Drawings

FIG. 1 is a schematic illustration of an auto-leveling OHT lift device of the overhead travelling crane handling system of the present invention;

FIG. 2 is a schematic view of a top mounting structure of the present invention;

FIG. 3 is an enlarged detail of the top securement structure connection of the present invention;

FIG. 4 is a detail view of the roof profile of the present invention;

FIG. 5 is a plan view of the connection of the leveling member and the connection unit of the present invention;

FIG. 6 is a perspective view of the connection of the leveling member and the connection unit of the present invention;

FIG. 7 is a schematic view of a profile frame of the present invention without a flexible synchronous drive;

FIG. 8 is a schematic view of a profile frame of the present invention with a flexible synchronous drive mounted thereto;

FIG. 9 is a schematic view of a winding element of the present invention;

FIG. 10 is a schematic diagram of a predetermined simulation curve according to the present invention;

FIG. 11 is a perspective view of the fracture detection mechanism of the present invention;

FIG. 12 is a plan view of the fracture detection mechanism of the present invention;

FIG. 13 is a schematic view of the motion of the rocker contact of the travel switch of the present invention;

FIG. 14 is a schematic diagram of an auto-leveling OHT lift method of the overhead travelling crane handling system of the present invention;

fig. 15 is a block flow chart of the invention for controlling the movement speed.

Reference numerals

1: A top fixing structure; 2: a lifting structure; 3: a flexible synchronous transmission structure; 4: a ranging structure; 5: a fracture detection mechanism;

11: a roof connection; 12: a leveling member; 13: a drive structure mount;

111: roof steel plates; 112: roof section bar;

1121: the upper side of the section bar is opened; 1122: the lower side of the section bar is opened; 1123: a hollow connection portion; 1124: a section bar jacket;

121: an adjusting bolt; 122: an adjusting nut; 123: leveling the support;

1211: a first right-handed thread structure; 1212: a first left-handed thread structure;

1221: a second left-handed thread structure; 1222: a second right-handed thread structure;

1231: a third right-handed thread structure; 1232: a mosaic structure;

131: a connection unit; 132: a profile frame; 133: a mounting base plate;

1311: a riser; 1312: a cross plate; 1313: a first right angle triangular stiffener; 1314: a second right triangle reinforcement;

31: a driving member; 32: a winding part; 33: a flexible conveyor belt;

321: a wheel core; 322: a pressing plate; 323: a press plate bolt; 324: a conveyor belt exit region; 325: winding a hub;

51: a fixing seat; 52: a seesaw; 53: a spring support structure; 54: a tensioning wheel; 55: a travel switch;

531: a spring; 532: an upper spring support pin; 533: a lower spring support pin; 534: a stand column base;

551: a travel switch wheel; 552: a travel switch contact; 553: and 554 a contact surface of the travel switch and the rocker.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

As used herein, the singular forms "a", "an", "the" and "the" are intended to include the plural forms as well, unless expressly stated otherwise, as understood by those skilled in the art. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

First embodiment

As shown in fig. 1, the present embodiment provides an auto-leveling OHT lift device of an overhead traveling crane handling system for raising or lowering an OHT trolley of the overhead traveling crane handling system to a workstation or a storage area adapted to different heights when carrying a material using the OHT trolley, the OHT lift device comprising: a top fixing structure 1, a lifting structure 2, at least three flexible synchronous transmission structures 3 and a control structure;

the upper part of the top fixing structure 1 is connected with a roof, the lower part of the top fixing structure 1 is connected with the upper parts of at least three flexible synchronous transmission structures 3, the upper surface of the lifting structure 2 is connected with the lower parts of at least three flexible synchronous transmission structures 3, the center point of a graph formed by connecting points of the at least three flexible synchronous transmission structures 3 on the lifting structure 2 is the center point of gravity of the lifting structure 3, and the control structure is electrically connected with the at least three flexible synchronous transmission structures 3;

The at least three flexible synchronous transmission structures 3 are configured to simultaneously receive pulse signals sent by the control structure, and feed back the sagging lengths of the flexible synchronous transmission structures 3 to the control structure in real time, the control structure calculates the sagging length limit deviations of all the flexible synchronous transmission structures 3, when the limit deviations exceed a preset range, the control structure adjusts the frequency of the pulse signals sent to the flexible synchronous transmission structures 3 influencing the calculation results of the limit deviations so as to automatically adjust the sagging lengths of the flexible synchronous transmission structures 3 in real time, and ensures that the limit deviations of the sagging lengths of all the flexible synchronous transmission structures 3 are within the preset range in the motion control process, so that the automatic leveling of the lifting structures 2 is realized when the lifting structures 2 are adopted to lift or descend, after leveling, the lifting structures 2 form stable and non-swing lifting platforms, and the OHT trolley is stably lifted or lowered to a required work station or a required height area by means of the lifting platforms so as to carry materials.

In this embodiment, for example, the top fixing structure 1 is disposed at the uppermost end of the OHT lifting device of the automatic leveling system of the overhead travelling crane handling system, and the top fixing structure 1 may be formed by using a profile connection or a sheet metal welding. The upper part of the top fixing structure 1 is fixedly connected with a roof profile, 4 driving pieces 31 are arranged at the lower part of the top fixing structure, a servo motor or an asynchronous motor can be adopted as a power source for the driving pieces 31, each driving piece 31 controls the rotation of one winding piece 32 through a rotating shaft, the winding pieces 32 are mainly made of aluminum alloy materials at present, and the diameter of each winding piece needs to meet the minimum bending radius of a flexible conveying belt 33. One end of each flexible conveyor belt 33 is clamped in the winding part 32, and the other end is fixedly connected with the lifting structure 2 below, in the embodiment, a belt is adopted as the flexible conveyor belt 33, a belt core type material can adopt a steel core wire, an aramid fiber or a stainless steel core wire, a filling material can adopt polyurethane rubber, and in order to ensure the load, a bending-resistant steel core and a polyurethane elastomer filling material are adopted. Four belts are evenly distributed to keep the lifting structure 2 level.

The specific structure of the self-leveling OHT lift device is described in detail below:

As shown in fig. 2 and 3, the top fixing structure 1 specifically includes: roof connection element 11, several leveling elements 12, and transmission structure installation element 13; the roof connecting piece 11 is connected with a roof; the transmission structure mounting piece 13 is connected with at least three flexible synchronous transmission structures 3 and is used for mounting and fixing at least three flexible synchronous transmission structures 3; the upper parts of the leveling pieces 12 are connected with the roof connecting pieces 11, and the lower parts of the leveling pieces are connected with the transmission structure mounting pieces 13 and used for leveling the transmission structure mounting pieces 13.

The roof connecting piece 11 comprises a roof steel plate 111 and a plurality of roof profiles 112, the roof steel plate 111 is horizontally arranged on a roof, the roof profiles 112 are vertically arranged on the roof steel plate 11, and the roof steel plate 111 and the roof profiles 112 belong to the self construction of a factory building. In the present embodiment, the roof steel sheet 111 is a cold-rolled steel sheet.

In this example, as shown in fig. 4, the roof profile 112 includes a profile upper side opening 1121, a profile lower side opening 1122, a hollow connection 1123, and a profile outer jacket 1124; the profile upper side opening 1121 is connected with the roof steel plate 111 by bolts, the profile lower side opening 1122 is connected with the leveling piece 12, and the hollow connecting part 1123 connects the profile upper side opening 1121 and the profile lower side opening 1122; the profile jacket 1124 is sleeved on the integral outer part formed by the profile upper side opening 1121, the hollow connecting part 1123 and the profile lower side opening 1122, and is used for reinforcing the integral structure of the roof profile 1123.

The leveling member 12 adopts a structure including a leveling bolt, a leveling screw and a leveling pin, in this embodiment, the leveling member 12 is a leveling bolt, and is disposed below the roof section bar 112, the upper portion of the leveling bolt is in threaded connection with the roof section bar 112, and the lower portion of the leveling bolt is in threaded connection with the connection unit 131 on the transmission structure mounting member 13, so that the leveling member has the function of adjusting the levels of the plurality of connection units 131.

In this embodiment, as shown in fig. 5 and 6, the leveling member 12 includes an adjusting bolt 121, an adjusting nut 122, and a leveling bracket 123;

The upper part of the adjusting bolt 121 is provided with a first right-handed thread structure 1211, the lower part of the adjusting bolt is provided with a first left-handed thread structure 1212, the first right-handed thread structure 1211 is connected with the roof profile 112, and the first left-handed thread structure 1212 is connected with the adjusting nut 122;

the adjusting nut 122 has a second left-handed thread structure 1221 at an upper portion and a second right-handed thread structure 1222 at a lower portion, and the second left-handed thread structure 1221 is connected with the first left-handed thread structure 1212;

The leveling support 123 has a third right-handed screw structure 1231 at an upper portion thereof and an insert structure 1232 at a lower portion thereof for fixedly connecting with the connection unit 131, and the third right-handed screw structure 1231 is connected with the second right-handed screw structure 1222. The damascene structure 1232 makes the connection with the connection unit 131 more firm.

When the adjusting nut 122 is rotated clockwise, the adjusting bolt 121 moves downwards relative to the adjusting nut 122 under the driving of the adjusting nut 122, the leveling support 123 moves upwards relative to the adjusting nut 122, the distance between the roof connecting piece 11 and the transmission structure mounting piece 13 is shortened, and the height of the transmission structure mounting piece 13 is increased;

When the adjusting nut 122 is rotated counterclockwise, the adjusting bolt 121 moves upward relative to the adjusting nut 122 under the driving of the adjusting nut 122, the leveling support 123 moves downward relative to the adjusting nut 122, the distance between the roof connection member 11 and the driving structure mounting member 13 is lengthened, and the height of the driving structure mounting member 13 is lowered.

The transmission structure mounting member 13 comprises a connecting unit 131, a profile frame 132 and a mounting base plate 133, wherein the connecting unit 131 is used for fixing the profile frame 132 and the mounting base plate 133, and is connected with the leveling member 12, the profile frame 132 is arranged above the mounting base plate 133 in parallel, and the mounting base plate 133 is used for mounting and fixing at least three flexible synchronous transmission structures 3. The plurality of connecting units 131 are uniformly connected around the profile frame 132 by bolts for lifting the profile frame 132, the lower part of the profile frame 132 is provided with a mounting base plate 133, and the mounting base plate 133 is provided with threaded holes for mounting the driving member 31.

As shown in fig. 6, the connection unit 131 includes a riser 1311, a cross-plate 1312, a first right triangle reinforcement 1313, and a second right triangle reinforcement 1314;

The vertical plate 1311 is used for fixing the profile frame 132 and the mounting base plate 133, and the profile frame 132 and the mounting base plate 133 are arranged at the top end of one surface of the vertical plate 1311;

the transverse plate 1312 is vertically arranged at the bottom end of the other surface of the vertical plate 1311, and the upper surface of the transverse plate 1312 is connected with the leveling piece 12;

The first right triangle reinforcement 1313 and the second right triangle 1314 are disposed on two sides of the vertical plate 1311 and the horizontal plate 1312, and two sides of the first right triangle reinforcement 1313 and the second right triangle reinforcement 1314, which are perpendicular to each other, are fixedly connected with the vertical plate 1311 and the horizontal plate 1312, respectively.

The above-mentioned connection unit 131 forms a lower connection structure, and since the distance of the roof from the driving structure mounting member 13 is too small, the adjustment range of the leveling member 12 can be increased by lowering the height of the connection surface.

In this embodiment, an example of a specific structure of the profile frame 132 is shown in fig. 7 and 8, where fig. 7 is a schematic view of the profile frame without the flexible synchronous transmission structure, and fig. 8 is a schematic view of the profile frame with the flexible synchronous transmission structure 3, where the pulley protrudes out of the profile frame 132, the mounting base plate 133 needs to be hollowed out, and the structure of the profile frame 132 needs to avoid the flexible synchronous transmission structure 3.

The upper part of the flexible synchronous transmission structure 3 is connected with the lower part of the top fixing structure 1, and the lower part is connected with the lifting structure 3, so that the lifting structure 3 can be lifted by theoretically comprising three flexible synchronous transmission structures 3, and an optimal mode is that one flexible synchronous transmission structure 3 is respectively arranged at four corners of the lifting structure 3, and more flexible synchronous transmission structures 3 can be arranged for lifting the lifting structure 3 if necessary. In this embodiment, as shown in fig. 1, a flexible synchronous transmission structure 3 is disposed at each of four corners of the lifting structure 3.

For any one of the flexible synchronous transmission structures 3, each comprises a driving member 31, a winding member 32 and a flexible conveying belt 33;

The driving piece 31 is installed below the top fixing structure 1, the driving piece 31 controls the winding piece 32 to rotate, wherein the driving piece 31 adopts a structure comprising a servo motor or an asynchronous motor, and the driving piece 31 adopts a structure comprising a rotating shaft control, a ball screw and a gear rack to drive the winding piece 32 to rotate;

One end of the flexible conveying belt 33 is clamped in the winding part 32, the other end of the flexible conveying belt 33 is fixedly connected with the lifting structure 3 below, and the sagging length of the flexible conveying belt 33 is adjusted by rotating the winding part 32 so as to control the lifting structure 3 to ascend or descend, wherein the flexible conveying belt 33 comprises any one of a belt, a synchronous belt and a chain.

Further, the driving element 31 is configured to receive a pulse signal sent by a driver, control the rotation speed of the driving element 31 according to the frequency of the pulse signal, and rotate a preset fixed angle according to a preset direction when the driving element 31 receives a pulse signal sent by the driver, wherein the preset fixed angle is a preset step angle of the driving element;

The driving member 31 is configured to control the angular displacement amount of the driving member 31 by controlling the number of the pulse signals received in a unit time to control the rotation speed of the driving member 31, and the rotation speed of the driving member 31 multiplied by the diameter of the winding portion of the flexible conveyor belt 33 of the winding member 32 and multiplied by the circumference ratio is the speed of the flexible conveyor belt rising or falling, that is, the speed of the lifting structure 3 rising or falling. The above calculation process is expressed as: v1=v2×d×pi, where v1 is a speed of the lifting structure to rise or fall, v2 is a rotation speed of the driving member, r/s, d is a diameter of a winding portion of the flexible conveyor belt of the winding member, and m, pi is a circumferential rate.

Accordingly, the number of pulse signals to be received in a unit time can be reached by performing reverse thrust in the same manner as above according to the required speed of the lifting structure 3 to rise or fall, so as to realize the change of the speed of the lifting structure 3 to rise or fall by controlling the number of pulse signals to be received in the unit time.

Further, as shown in fig. 9, in this embodiment, the winding part 32 specifically includes: wheel core 321, platen 322, platen bolt 323, conveyor belt exit area 324, and winding hub 325;

The center of the wheel core 321 is provided with a rotating shaft mounting hole for mounting a rotating shaft, a bulge is arranged on the rotating shaft mounting hole and used for clamping the rotating shaft, the surface of the wheel core corresponding to the bulge is of a trapezoid bulge structure, and the other side of the wheel core is of a plane structure;

The flexible conveyer belt 33 one end twines on the wheel core 321, the wheel core 321 the plane structure with be provided with the screw hole on the parallel face of clamp plate 322, be provided with on the flexible conveyer belt 33 with the conveyer belt hole that the screw hole corresponds, wherein, screw hole and conveyer belt hole are preferred to be set up to 2 in this embodiment, and the conveyer belt hole uses the puncher to drill on the flexible conveyer belt 33.

The platen bolt 323 is configured to pass through the platen 322 and the belt hole, and be screwed into the screw hole of the wheel core 321, so as to tightly lock the flexible belt 33 and the wheel core 321;

The belt exit area 324 is configured to draw the flexible belt 33 from the area where the wheel core 321 is located to wind around the winding hub 325 disposed on the outer circumference of the wheel core 321.

Further, the OHT lifting device for self-leveling of the overhead travelling crane handling system of the present embodiment further includes: a first lifting structure identification unit and a second lifting structure identification unit; the first lifting structure identification unit is arranged at a position where the lifting structure 2 needs to be decelerated, and the second lifting structure identification unit is arranged at a position where the lifting structure 2 needs to be immediately stopped; the lifting structure 2 is configured to start acceleration operation with a first acceleration when starting the motion control, to start constant operation with a first preset operation speed when accelerating to the first preset operation speed, to start deceleration operation with a second acceleration when the lifting structure 2 is operated to a position where the first lifting structure identification unit is located, to start constant operation with the second preset operation speed when decelerating to the second preset operation speed, and to stop the lifting structure operation immediately when the lifting structure 2 is operated to a position where the second lifting structure identification unit is located.

For example, in the present embodiment, when the control system issues a command to activate all driving members 31 at the same time, all hoisting members 32 rotate simultaneously, and the hoisting members 32 will drive the lifting structure 2 to rise horizontally. The operation speed of the lifting structure 2 is set to be 10 m/min, namely 0.16m/min (namely a first preset operation speed), the initial acceleration is required to be accelerated to be 0.16m/min (namely a first acceleration) within 0.03s, at the moment, the lifting structure 2 rises at a uniform speed, two photoelectric sensors (namely a first lifting structure identification unit and a second lifting structure identification unit) are arranged at the position of the lifting structure 2, when the lifting structure 2 operates to the first photoelectric sensor, the speed is reduced to be 0.1m/s (namely a second acceleration) within 0.3s, the lifting structure 2 operates to be the second photoelectric sensor at a speed of 0.1m/s (namely a second preset operation speed), and the lifting structure 2 is required to stop operating immediately.

Further, in order to measure the sagging length of the flexible synchronous transmission structure 3, a plurality of ranging structures 4 corresponding to the flexible synchronous transmission structure 3 one by one are arranged;

The distance measuring structures 4 are arranged close to the flexible synchronous transmission structures 3 in a one-to-one correspondence manner, and are configured to measure the sagging length of the flexible synchronous transmission structures 3 when the lifting structures 2 perform the motion control, and record and transmit the sagging length to a controller in real time; wherein, the distance measuring structure 4 adopts a structure comprising a laser distance measuring instrument or a microwave distance measuring instrument.

The controller calculates the sagging lengths of all the received flexible synchronous transmission structures 3, calculates the limit deviation of the sagging lengths, and when the limit deviation exceeds the preset range, selects to automatically adjust the sagging lengths of the flexible synchronous transmission structures 3 influencing the calculation result of the limit deviation in real time so as to adjust the limit deviation to be within the preset range; wherein the limit deviation = length maximum value-length minimum value, the real-time automatic adjustment of the sagging length of the flexible synchromesh transmission structure 3 is configured to adjust the sagging length in real time by adjusting the speed of ascent or descent of the lifting structure 2.

Similarly, when the sagging length of the flexible synchronous transmission structure 3, which affects the calculation result of the limit deviation, is automatically adjusted in real time, the motor rotation speed is controlled by using the control pulse transmission frequency, and the specific pulse transmission frequency needs to be calculated according to the deviation of the actual sagging length and the speed of the deviation.

Further, the ranging structure is configured to acquire the sagging lengths of all the flexible synchronous transmission structures by timing synchronous detection of the distance from the ranging structure to a detection point on the lifting structure corresponding to the current flexible synchronous transmission structure; calculating deviation data of the sagging length of the other flexible synchronous transmission structures and the reference length by taking the sagging length of one flexible synchronous transmission structure as the reference length; and converting the deviation data into a rotation angle instruction required by a driving piece, and sending the rotation instruction to the driving piece by the driver to position, so that the OHT crown block can stably lift.

Namely, the principle of the automatic leveling algorithm of the present invention is:

the planar distance of the lifting structure is detected by using a plurality of distance measuring structures respectively, the distance is detected in real time in the process of loading or unloading the OHT crown block, and then a certain detection point is used as a reference point for comparison, wherein the compared deviation is the data to be corrected. The deviation data is processed through the operation of the driver and is converted into an instruction of the driving piece corresponding to the motor, and the motor operates to perform distance correction and compensation, so that the lifting structure is kept at an allowable gradient, and finally the OHT overhead travelling crane is stably reached.

For example, the invention selects 4 laser distance sensors as the distance measuring structure to detect 4 angles of the plane of the lifting structure, the maximum required distance is 4m, the maximum allowable response time is 10ms, and the analog output mode is adopted.

Deviation calculation and processing-controller (driver). The invention selects the PLC controller, the analog input acquisition rate is 80us/ch, and the timer interrupt is set for 10ms. And (3) calculating deviation:

D1 The 1 st point of Y1-Y1 deviates, and no deviation (with the detection point Y1 as the reference point);

D2 =y1-Y1, point 2 offset;

d3 =y3-Y1 3 rd point deviation;

d4 =y4-Y1, 4 th point deviation;

and acquiring and calculating deviation data in 10ms, and converting the deviation data into a rotation angle instruction required by the motor. The angle is calculated as follows:

θ=d2×180/n/R, taking point 2 as an example, R is the belt take-up radius, which can be calculated by a servo feedback encoder.

The invention adopts the servo motor, and can accurately position. And the crown block is positioned by receiving a rotation instruction sent by the controller, and finally, the crown block stably ascends and descends.

In addition, the real-time detection of the invention can be ensured, and specifically comprises the following steps: the invention selects the Siemens laser ranging sensor and analog output mode, the maximum response time is 10ms, and the response time is slower, but the requirements are completely met. The PLC acquires deviation data in a 10ms timing interruption mode, namely, sensor data are acquired every 10ms, and 100 times can be acquired for 1 s. Each acquisition is to uniformly acquire all channels, and each channel data has no time difference, namely Y1-Y4 are obtained at the same time. The maximum operating speed of the lifting structure is 10m/min, and the maximum deviation of 10ms is 1.67mm.

The deviation between the maximum value and the minimum value of the measured values of the four sensors is set to be not more than 0.5mm, and when the deviation between the measured values of the four sensors is measured at a certain moment to be more than 0.5mm, the PLC controls the position servo motor to correct.

The correction idea is as follows: the position servo motor receives a speed regulation command, increases or reduces the rotation angular velocity within 2-6 ms, further adjusts the belt winding velocity, finally enables four belts to recover to a qualified deviation range, simultaneously monitors the belt length in real time, detects the regulation effect, if the deviation value fed back at the next 10ms does not reach a qualified value, the PLC continuously sends the regulation command to the motor, the position private motor receives the speed regulation command, and continuously increases or reduces the rotation angular velocity within 2-6 ms so as to enable the deviation of the four belts to be kept within a required value.

The operation scanning time of the controller PLC is also less than 10ms, so that a correction instruction can be timely sent. The distance measuring sensor has the same effect (the response time is less than or equal to 10 ms) by adopting a communication output mode.

In addition, as shown in fig. 10, a simulation curve of the running speed and the acceleration obtained by simulation according to the data is preset in software corresponding to the driver, so as to ensure the stable ascending or descending of the OHT trolley. When the lifting structure moves up and down, judging the current use state of each driver according to the read sagging length of the ranging structure and the derivative (jerk) of the distance change rate of the sagging length, and comparing the use state of each driver with the simulation curve for adjustment; and meanwhile, the balance problem of the four drivers is concerned, and the rotation angular speed of the drivers is finely adjusted in real time, so that all the drivers are in a balanced state.

Further, as shown in fig. 11 and 12, the self-leveling OHT lifting device of the present embodiment further includes: a plurality of fracture detection mechanisms 5 which are in one-to-one correspondence with the flexible synchronous transmission structures 3;

Any one of the fracture detection mechanisms 5 respectively comprises a fixed seat 51, a rocker 52, a spring supporting structure 53, a tensioning wheel 54 and a travel switch 55;

The fixing seat 51 is mounted on the lifting structure 2 through a bolt, the middle position of the rocker 52 is rotatably connected with the middle position of the fixing seat 51, and the rocker 52 takes the middle position as a fixed point to realize rocker movement;

the upper end of the spring supporting structure 53 is a fixed end, the lower end is a movable end, the tensioning wheel 54 is mounted at the front end of the rocker 52, and the movable end of the spring supporting structure 53 is fixed at one side of the rear end of the rocker 52;

The rear end of the rocker 52 is pulled up by the spring supporting structure 53, and the tensioning wheel 54 at the front end presses the flexible conveyor belt 33 downwards to realize the function of tensioning the flexible conveyor belt 33;

The travel switch runner 551 of the travel switch 55 is disposed on the other side opposite to the spring supporting structure 53 at the rear end of the rocker 52, when the pulling force of the flexible conveyor belt 33 is within the first preset range, the distance range of the rear end of the rocker 52 is within the second preset range, at this time, the travel switch runner 551 contacts the surface at the rear end of the rocker 52, the travel switch 55 is in a closed state under the pressure of the travel switch runner 551, otherwise, when the distance range of the rear end of the rocker 52 is not within the second preset range, the travel switch runner 551 is separated from the rear end contact surface of the rocker 52, and the travel switch 55 is determined to be broken due to the fact that the travel switch runner 551 is not stressed.

For example, the outer diameter of the spring 531 of the spring support structure 53 is set to 16mm, the free length of the spring 531 under no tension is 100mm, the lifting structure 2 itself weighs 50KG, the lifting structure 2 and the OHT vehicle weigh together 200KG, the spring 531 stretches to 110mm when the spring is under 50KG force, and the spring 531 stretches to 130mm when the spring is under 200KG force. When the travel switch runner 551 of the travel switch 55 is pressed against the rocker 52, the contact of the travel switch 55 is kept pressed in the off state, and when the spring 531 is elongated in the range of 110mm to 130mm, the travel switch runner 551 is not separated from the rocker contact surface, and the travel switch contact is always pressed and turned off. When the flexible conveyor belt 33 breaks, the spring 531 will return to the free length of 100mm directly, and at this time, the travel switch runner 551 breaks away from the rocker contact surface, the travel switch contact is opened without being pressed, and the PLC recognizes that the flexible conveyor belt 33 breaks, and proceeds to the next operation.

As shown in fig. 13, the contact point movement of the travel switch 55 and the rocker 52 is schematically illustrated. In this embodiment, the total length of the contact surface of the rocker and the travel switch is 35mm.

Position 1: rocker 52 bottom edge position.

Position 2: the lifting structure 2 is loaded with 50kg, and the contact point of the travel switch roller and the rocker is positioned.

Position 3: the lifting structure 2 loads 200kg, and the contact point position of the travel switch roller and the rocker is located.

Position 4: the top edge of rocker 52.

The spring support structure 53 includes: a spring 531, an upper spring support pin 532, a lower spring support pin 533, a post seat 534; the upright post seat 534 is mounted on the lifting structure 2 through a bolt, the upper spring support pin 532 is fixedly connected with the upper end of the upright post seat 534, the upper end of the spring 531 is fixedly connected with the upper spring support pin 532 as the fixed end, and the lower end of the spring 531 is fixedly connected with the lower spring support pin 533 as the movable end; the lower spring supporting pin 533 is connected to the rear end side of the rocker 52.

The travel switch 55 includes: the travel switch runner 551, the travel switch contact 552, and the travel switch bracket 553; the travel switch support 553 is fixed on the lifting structure 2, and the travel switch contact 552 is fixed on one side of the travel switch support 553, which is close to the rocker 52; the front end of the travel switch contact 552 is provided with the travel switch runner 551, and the travel switch runner 551 slides on the contact surface of the rocker 52 and the travel switch.

Second embodiment

The embodiment provides an overhead traveling crane handling system, including: an auto-leveling OHT lifting device and OHT trolley of the overhead travelling crane handling system as in the first embodiment;

Third embodiment

As shown in fig. 14, the present embodiment provides a lifting method of an OHT lifting device based on auto leveling of an overhead travelling crane handling system as in the first embodiment, comprising the steps of:

S1: and placing the OHT trolley at the middle position of the lifting structure, and simultaneously issuing a starting instruction to at least three flexible synchronous transmission structures by the controller, wherein at least three flexible synchronous transmission structures simultaneously control the lifting structure to ascend or descend, so as to drive the lifting structure to ascend or descend.

Specifically, firstly, the OHT trolley is placed at the middle position of the lifting structure, the control system simultaneously issues an instruction to start the driving piece, the hoisting piece simultaneously rotates, and the hoisting piece drives the lifting structure to horizontally ascend.

Specifically, in this embodiment, a ranging structure 4 is disposed beside each winding element 32, and the sagging length of the flexible conveyor belt 33 during the lifting process of the lifting structure 2 is measured in real time, in this embodiment, the ranging structure 4 may use a laser ranging device or a microwave ranging device, the precision is required to be 0.1mm, the measurement data of which is recorded in real time by an analog module or another protocol and transmitted to the controller, and we set that the distance deviation measured by the four ranging structures 4 is less than 0.5mm at the same time in any period.

When it is found that the distance value of any one ranging structure 4 causes the limit deviation to exceed the set value of 0.5mm, the limit deviation= (maximum value-minimum value), which means that the sagging length of the flexible conveyor belt 33 exceeds the set value, a signal is immediately sent to the driving member 31 controlling the flexible conveyor belt 33 to adjust the winding speed of the flexible conveyor belt 33 in time (when lifting, if the flexible conveyor belt 33 is too long, the wheel winding speed is increased, if the flexible conveyor belt 33 is too short, the wheel winding speed is decreased, and when dropping, if the flexible conveyor belt 33 is too long, the wheel winding speed is increased, so as to ensure that the lengths of the four flexible conveyor belts 33 are consistent, the set value can be adjusted up or down according to the field situation.

When it is found that the distance value of any two ranging structures 4 causes the limit deviation to exceed the set value of 0.5mm, which means that the length of the two flexible conveyor belts 33 exceeds the set value, a signal is immediately sent to the driving member 31 for controlling the two flexible conveyor belts 33, and the winding speed of the two flexible conveyor belts 33 is timely adjusted to ensure that the lengths of the four flexible conveyor belts 33 are consistent, and the set value can be adjusted to be larger or smaller according to the swinging condition of the lifting structure 2.

In this way the problem of swaying of the lifting structure 2 due to the difference in sagging length of the flexible conveyor belt 33 is completely eliminated.

As shown in fig. 15, the communication process of speed adjustment by the method of the present invention is: the ST voice or the ladder diagram is used for manually inputting the running speed to the PLC, the PLC sends an instruction to the motor driver, and the motor is driven to run; the distance measuring mechanism (distance measuring sensor) transmits the measured information to the PLC through digital-to-analog conversion by an analog quantity module; the PLC sends the regulation and control information to the motor drives again through operation, and each drive operates according to the latest operation speed, so that the purpose of adjusting the length of the flexible conveyor belt is achieved.

A computer readable storage medium storing computer code which, when executed, performs a method as described above. Those of ordinary skill in the art will appreciate that all or part of the steps in the various methods of the above embodiments may be implemented by a program to instruct related hardware, the program may be stored in a computer readable storage medium, and the storage medium may include: read Only Memory (ROM), random access Memory (RAM, random Access Memory), magnetic or optical disk, and the like.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above examples, and all technical solutions belonging to the concept of the present invention belong to the protection scope of the present invention. It should be noted that modifications and adaptations to the present invention may occur to one skilled in the art without departing from the principles of the present invention and are intended to be within the scope of the present invention.

It should be noted that the above embodiments can be freely combined as needed. The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.

Claims

1. An OHT lifting device for automatically leveling an overhead travelling crane handling system, wherein the OHT lifting device is adapted to raise or lower an OHT trolley of the overhead travelling crane handling system to a workstation or storage area adapted to different heights when the OHT trolley is used for material handling, the OHT lifting device comprising: the device comprises a top fixing structure, a lifting structure, at least three flexible synchronous transmission structures and a control structure;

The control structure calculates limit deviations of the sagging lengths of all the flexible synchronous transmission structures, when the limit deviations exceed a preset range, the control structure adjusts the frequency of the pulse signals sent to the flexible synchronous transmission structures influencing the calculation result of the limit deviations so as to automatically adjust the sagging lengths of the flexible synchronous transmission structures in real time, the limit deviations of the sagging lengths of all the flexible synchronous transmission structures are ensured to be within the preset range in the motion control process, automatic leveling of the lifting structures is realized when the lifting structures are adopted to lift or descend the OHT trolley, after leveling, the lifting structures form stable and non-swaying lifting platforms, and the OHT trolley is stably lifted or descended to a working station or a storage area with the aid of the lifting platforms so as to carry materials;

further comprises: a plurality of ranging structures which are in one-to-one correspondence with the flexible synchronous transmission structures;

Wherein, the distance measuring structure comprises a laser distance measuring instrument or a microwave distance measuring instrument;

The distance measuring structure is configured to acquire the sagging lengths of all the flexible synchronous transmission structures by detecting the distance from the distance measuring structure to a detection point corresponding to the current flexible synchronous transmission structure on the lifting structure at a timing synchronous;

converting the deviation data into a rotation angle instruction required by a driving piece, and sending the rotation instruction to the driving piece by the driver to position, so that the OHT trolley can stably lift;

The drivers are configured to be provided with corresponding software simulation curves of running speed and acceleration simulated according to data in advance, when the lifting structure moves up and down, the use states of the drivers are judged according to the derivative of the distance change rate of the read sagging length and the use states of the drivers are compared with the simulation curves to be adjusted;

Simultaneously, the rotation angular speed of the driving piece is finely adjusted in real time, so that all the driving pieces are in a balanced state;

any one flexible synchronous transmission structure specifically comprises: the driving piece, the winding piece and the flexible conveying belt;

the driving piece is arranged below the top fixing structure and controls the winding piece to rotate, wherein the driving piece adopts a servo motor or an asynchronous motor and drives the winding piece to rotate;

One end of the flexible conveyor belt is clamped in the hoisting piece, the other end of the flexible conveyor belt is fixedly connected with the lifting structure below, and the hoisting piece is rotated to adjust the sagging length of the flexible conveyor belt so as to control the lifting structure to ascend or descend;

the driving piece further includes:

The speed of the flexible conveyor belt rising or falling, that is, the speed of the lifting structure rising or falling is v1=v2×d×pi, where v1 is the speed of the lifting structure rising or falling, v2 is the rotation speed of the driving member, r/s is the diameter of the winding portion of the flexible conveyor belt of the winding member, and m is the circumferential rate;

Further comprises: the plurality of fracture detection mechanisms are in one-to-one correspondence with the flexible synchronous transmission structures;

The travel switch rotating wheel of the travel switch is arranged on the other side of the rear end of the rocker opposite to the spring supporting structure, when the pulling force of the flexible conveyor belt is in a first preset range, the distance range of the rear end of the rocker is in a second preset range, at the moment, the travel switch rotating wheel is on the contact surface of the rear end of the rocker, the travel switch is in a closing state under the pressure action of the travel switch rotating wheel, otherwise, when the distance range of the rear end of the rocker is not in the second preset range, the travel switch rotating wheel is separated from the contact surface of the rear end of the rocker, and the travel switch is opened because the travel switch rotating wheel is not stressed, and is considered to be broken;

The spring support structure includes: the device comprises a spring, an upper spring supporting pin, a lower spring supporting pin and a stand column seat;

2. The self-leveling OHT lift device of an overhead travelling crane handling system of claim 1, further comprising:

The controller is configured to calculate the sagging lengths of all the received flexible synchronous transmission structures, calculate the limit deviation of the sagging lengths, and select to automatically adjust the sagging lengths of the flexible synchronous transmission structures, which affect the calculation result of the limit deviation, in real time when the limit deviation exceeds the preset range, so as to adjust the limit deviation to be within the preset range;

3. The self-leveling OHT lifting device of an overhead travelling crane handling system according to claim 1, wherein the winch comprises in particular: the wheel core, the pressing plate bolt, the conveyor belt outlet area and the winding hub;

4. The self-leveling OHT lift device of an overhead travelling crane handling system of claim 1, further comprising: a first lifting structure identification unit and a second lifting structure identification unit;

5. The overhead travelling crane handling system self-leveling OHT lifting device of claim 1, wherein the top fixture structure specifically comprises: roof connecting piece, several leveling pieces and transmission structure installing piece;

The roof connecting piece is connected with a roof;

6. The self-leveling OHT lift device of an overhead travelling crane handling system of claim 5, further comprising:

7. The overhead travelling crane handling system self-leveling OHT lifting mechanism of claim 6, wherein the roof profile comprises a profile upper side opening, a profile lower side opening, a hollow connection, and a profile jacket;

8. The overhead travelling crane handling system self-leveling OHT lifting appliance of claim 7, wherein the leveling member comprises an adjustment bolt, an adjustment nut, and a leveling bracket;

9. The self-leveling OHT lift system of claim 7, wherein said connection unit comprises a riser, a cross plate, a first right angle triangular stiffener and a second right angle triangular stiffener;

10. The self-leveling OHT lift device of an overhead travelling crane handling system of claim 1, wherein,

The travel switch comprises: the travel switch rotating wheel, the travel switch contact and the travel switch bracket are arranged on the travel switch rotating wheel;

11. A crown block handling system, comprising: self-leveling OHT lift device and OHT trolley of an overhead travelling crane handling system according to any of claims 1-10;

12. Lifting method of an auto-leveling OHT lifting device based on a crown block handling system according to any of claims 1-10, comprising the steps of: