CN112520655A - Arm support telescopic control method, arm support control system and aerial work platform - Google Patents
Arm support telescopic control method, arm support control system and aerial work platform Download PDFInfo
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- CN112520655A CN112520655A CN202011350495.2A CN202011350495A CN112520655A CN 112520655 A CN112520655 A CN 112520655A CN 202011350495 A CN202011350495 A CN 202011350495A CN 112520655 A CN112520655 A CN 112520655A
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- oil cylinder
- telescopic oil
- telescopic
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- 238000000034 method Methods 0.000 title claims abstract description 16
- 238000001514 detection method Methods 0.000 claims description 9
- 230000003247 decreasing effect Effects 0.000 claims 1
- 230000001419 dependent effect Effects 0.000 claims 1
- 230000000694 effects Effects 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 2
- 230000004075 alteration Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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Classifications
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- 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
- 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
Abstract
The invention discloses a boom extension and retraction control method, a boom control system and an aerial work platform, wherein the control method comprises the following steps: when the arm support extends out, the front stage telescopic oil cylinder extends out to the maximum stroke L of the front stage telescopic oil cylinderiLength K ofiWhile gradually reducing the standard extension working flow to the target flow QiFinally with the target flow rate QiExtend to the maximum stroke LiThe rear stage telescopic oil cylinder extends out, and the extending working flow of the rear stage telescopic oil cylinder is in the extending length K'i‑1Gradually increasing within range to target flow Q'i‑1(ii) a When the arm support retracts, the retraction distance of the previous stage telescopic oil cylinder is the maximum stroke LiLength of (2)
While gradually reducing its standard retract working flow to the target flow
Finally, the target flow rate is used
Retracted to maximum stroke LiThe next stage of telescopic oil cylinder retracts, and the retraction working flow of the last stage of telescopic oil cylinder is within the retraction length
Gradually increasing within the range to a target flow
The invention controls the telescopic position of each stage of telescopic oil cylinder, so that the corresponding telescopic oil cylinder flexibly reaches the limit position of the oil cylinder and is flexibly started.
Description
Technical Field
The invention relates to the field of engineering machinery, in particular to a boom extension and retraction control method, a boom control system and an aerial work platform.
Background
With the rapid development of social economy, the ever-increasing high-altitude operation projects put forward more recent and higher demands on engineering machinery. To meet these needs, various aerial work platforms have come into use, including large aerial work platforms. A boom of a large-scale aerial work platform belongs to a large-scale structure, the boom generally realizes the telescopic function through a double telescopic oil cylinder, and the boom is in a large-height state after being unfolded, so that the control requirement on the boom is higher, and the control mode cannot be carried out by adopting a conventional scheme.
As shown in fig. 1, the boom of the large-sized aerial work platform includes: a base arm 101, a first telescopic arm 102, a second telescopic arm 103, the first telescopic arm 102 being arranged inside the base arm 101, the second telescopic arm 103 being arranged inside the first telescopic arm 102. As shown in fig. 2, the dual telescopic cylinder includes: a first telescopic cylinder 201 and a second telescopic cylinder 202. The first telescopic cylinder 201 drives the first telescopic arm 102 to extend and retract, and the second telescopic cylinder 202 drives the second telescopic arm 103 to extend and retract. When the arm support extends out, the second telescopic arm 103 extends out first, and then the first telescopic arm 102 extends out. When the arm support retracts, the second telescopic arm 103 retracts first, and then the first telescopic arm 102 retracts. At present, the conventional control mode only sets buffer rates in the fully-retracted in-place and fully-extended in-place of the arm support and a section of interval before the amplitude alarm, so that the impact of the arm support during fully-extended in-place and fully-retracted in-place and amplitude alarm is reduced, and the operation comfort is improved. However, when the second telescopic cylinder 202 is fully extended to the position and the first telescopic cylinder 201 is started to drive the first telescopic arm 102 to extend, the second telescopic cylinder 202 is fully retracted to the position and the first telescopic cylinder 201 is started to drive the first telescopic arm 102 to retract, no buffer control is considered, very large in-place impact and starting impact can be caused at the moment, the arm support and the working boom of the aerial work platform can greatly shake, and the phenomenon brings great potential safety hazard to aerial work and reduces the service life of the double telescopic cylinders.
Disclosure of Invention
The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a boom extension and retraction control method, a boom control system and an aerial work platform.
According to the boom extension control method of the embodiment of the first aspect of the invention, the boom comprises n sections of telescopic booms and n stages of telescopic oil cylinders, and the boom extension control method comprises the following steps: when the arm support extends out, the front stage telescopic oil cylinder extends out to the maximum stroke L of the front stage telescopic oil cylinderiLength K ofiWhile gradually reducing the standard extension working flow to the target flow QiFinally with the target flow rate QiExtend to the maximum stroke LiThe rear stage telescopic oil cylinder extends out, and the extending working flow of the rear stage telescopic oil cylinder is in the extending length K'i-1Gradually increasing within range to target flow Q'i-1(ii) a When the arm support retracts, the retraction distance of the previous stage telescopic oil cylinder is the maximum stroke LiLength of (2)
While gradually reducing its standard retract working flow to the target flow
Finally, the target flow rate is used
Retracted to maximum stroke LiThe next stage of telescopic oil cylinder retracts, and the retraction working flow of the last stage of telescopic oil cylinder is within the retraction length
Gradually increasing within the range to a target flow
Wherein, i and n are positive integers, i is 2, 3, …, n is not less than 2.
According to some embodiments of the invention, the working flow of each stage of telescopic oil cylinder during stretching is changed by controlling the input current of the electro proportional valve.
According to the boom control system of the embodiment of the second aspect of the present invention, the boom includes n sections of telescopic booms and n stages of telescopic cylinders, and the boom control system includes: detection device, controlling means, executive device. The detection device is used for detecting the total length L of the cantilever crane in extension. When the previous telescopic arm extends out, the control device is controlled according to the maximum stroke Li、…、Ln-1、LnJudging the maximum stroke L of the extension distance of the current movable telescopic oil cylinder by the L valueiHas a length of KiWhen it is time, the corresponding control command M is issuedi(ii) a When the rear telescopic arm just extends out, the control device is used for controlling the rear telescopic arm to move according to the maximum stroke Li、…、Ln-1、LnAnd judging that the extending length of the current movable telescopic oil cylinder is K 'by the L value'i-1When the range is within, a corresponding control command M 'is sent out'i-1(ii) a When the previous telescopic boom is retracted, the control device follows the maximum stroke L1、L2、…、Li-1Judging the maximum stroke L of the retracting distance of the current movable telescopic oil cylinder by the L valueiHas a length of
When it is time, the corresponding control command is issued
When the rear telescopic arm just retracts, the control device controls the rear telescopic arm to retract according to L1、L2、…、Li-1Judging the retracting length of the current movable telescopic oil cylinder by the L value
When the range is within, corresponding control command is sent out
The executing device is used for executing the control command MiGradually reducing the working flow of the current movable telescopic oil cylinder to a target flow Qi(ii) a The execution device is used for executing the control command M'i-1Gradually increasing the working flow of the current active telescopic oil cylinder to a target flow Q'i-1(ii) a The execution device is used for executing the control command according to the control command
Gradually reducing the working flow of the current movable telescopic oil cylinder to a target flow
The execution device is used for executing the control command according to the control command
Gradually increasing the working flow of the current movable telescopic oil cylinder to the target flow
According to some embodiments of the invention, the detection device is a length sensor mounted on the boom.
According to the third aspect embodiment of the invention, the aerial work platform comprises a base frame, a rotary table, an arm support arranged on the rotary table and the arm support control system in the above embodiment.
By adopting the boom extension control method, the boom control system and the aerial work platform provided by the invention, the extension positions of all stages of extension oil cylinders are controlled, so that the corresponding extension oil cylinders flexibly reach the oil cylinder limit positions and flexibly start, the switching impact is reduced, the arm support and the working fence of the aerial work platform shake are reduced, the operation comfort and the safety of the whole vehicle are improved, and the oil cylinder structures and the arm support structures of all stages of extension oil cylinders are protected to prolong the service life.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
FIG. 1 is a schematic structural diagram of an aerial work platform according to an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of a boom extension cylinder according to an embodiment of the invention;
fig. 3 is a flowchart of a boom extension and retraction control method according to an embodiment of the present invention;
fig. 4 is a block diagram of a boom control system according to an embodiment of the present invention;
fig. 5 is a control flowchart of the boom extension according to the embodiment of the present invention;
fig. 6 is a control flowchart of the boom retracting process according to the embodiment of the present invention.
Description of the drawings:
a basic arm 101, a first telescopic arm 102, a second telescopic arm 103, a first telescopic oil cylinder 201 and a second telescopic oil cylinder 202;
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.
In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper, lower, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.
In the description of the present invention, unless otherwise explicitly defined, terms such as arrangement, installation, connection and the like should be broadly construed, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the detailed contents of the technical solutions.
As shown in fig. 3, a boom extension and retraction control method according to an embodiment of the present invention includes an n-section telescopic boom and an n-stage telescopic cylinder, and the boom extension and retraction control method includes an extension control portion and a retraction control portion. When the arm support extends out, the front stage telescopic oil cylinder extends out to the maximum stroke L of the front stage telescopic oil cylinderiLength K ofiWhile gradually reducing the standard extension working flow to the target flow QiFinally with the target flow rate QiExtend to the maximum stroke LiThe rear stage telescopic oil cylinder extends out, and the extending working flow of the rear stage telescopic oil cylinder is in the extending length K'i-1Gradually increasing within range to target flow Q'i-1(ii) a When the arm support retracts, the retraction distance of the previous stage telescopic oil cylinder is the maximum stroke LiLength of (2)
While gradually reducing its standard retract working flow to the target flow
Finally, the target flow rate is used
Retracted to maximum stroke LiThe next stage of telescopic oil cylinder retracts, and the retraction working flow of the last stage of telescopic oil cylinder is within the retraction length
Gradually increasing within the range to a target flow
Wherein, i and n are positive integers, i is 2, 3, …, n is not less than 2.
In some embodiments of the invention, the working flow of the telescopic oil cylinder during telescopic operation is changed by controlling the input current of the electro proportional valve.
As shown in fig. 4, the boom control system of the embodiment of the present invention includes an n-section telescopic boom and an n-stage telescopic cylinder, and includes: detection device 300, control device 400, and execution device 500.
In order to more clearly understand the technical content of the present invention, as shown in fig. 5 and 6, a detailed description will be given below of a control process of extending and retracting a boom having two telescopic booms and two telescopic cylinders, where the boom structure is shown in fig. 1 and 2, and includes a first telescopic boom 102, a second telescopic boom 103, a first telescopic cylinder 201, and a second telescopic cylinder 202, where the first telescopic cylinder 201 drives the first telescopic boom 102 to extend and retract, and the second telescopic cylinder 202 drives the second telescopic boom 103 to extend and retract. It should be noted that, this is merely an exemplary illustration, and the present invention does not limit the value of n.
The detection device 300 detects the total length L of the boom extension.
Arm support extension control: when the second telescopic arm 103 is extended, the control device 400 is operated according to the maximum stroke L of the second telescopic cylinder 2022And the L value judges the maximum stroke L of the extending distance of the second telescopic arm 1032Has a length of K2When it is time, the corresponding control command M is issued2The execution device 500 executes the control command M2Controlling the working flow of the second telescopic oil cylinder 202 to be gradually reduced from the standard extension working flow to the target flow Q in proportion2And at a target flow rate Q2Extend to the maximum stroke L2At least one of (1) and (b); when the first telescopic arm 102 extends, the maximum stroke L of the second telescopic oil cylinder 202 is determined2And L value judges that the extending length of the first telescopic arm 102 is K'1When the range is within, a corresponding control command M 'is sent out'1Execution device 500 according to control command M'1Controlling the working flow of the first telescopic oil cylinder 201 to gradually increase in proportion until L reaches L2+K'1When the working flow rate of the first telescopic cylinder 201 is the target flow rate Q'1。Q'1Is a first telescopic oil cylinder201 operating flow at normal extension.
Arm support retraction control: when the control means 400 is operated according to the maximum stroke L of the first telescopic cylinder 201 when the second telescopic arm 103 is retracted1And the L value judges the maximum stroke L of the retracting distance of the second telescopic arm 1032Has a length of
When it is time, the corresponding control command is issued
The execution device 500 executes the control command
Controlling the working flow of the second telescopic cylinder 202 to be gradually reduced to the target flow in proportion
And at the target flow rate
Retracted to maximum stroke L2At least one of (1) and (b); when the first telescopic arm 102 is retracted, it is according to the maximum stroke L of the first telescopic cylinder 2011And the L value determines that the first telescopic arm 102 is retracted in length
When the range is within, corresponding control command is sent out
The execution device 500 executes the control command
Controlling the working flow of the first telescopic oil cylinder 201 to gradually increase in proportion until L reaches
When the working flow of the first telescopic oil cylinder 201 is the target flow
The working flow rate when the first telescopic cylinder 201 is normally retracted.
In this example, K2、K'1、
The buffer distance is a constant for determining the buffer distance and can be adjusted according to different aerial work platforms and different working conditions. The actuator 500 is an electro proportional valve for controlling the working flow of the first and second telescopic cylinders 201 and 202, and the working flow of the corresponding telescopic cylinder can be changed by changing the input current of the electro proportional valve.
In some embodiments of the present invention, the detection device 300 is a length sensor mounted on the boom.
As shown in fig. 1, the aerial work platform according to the embodiment of the present invention includes a base frame 600, a turntable 700, an arm support disposed on the turntable 700, and an arm support control system in the above embodiment.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.
Claims (5)
1. A boom extension control method is characterized by comprising the following steps:
s100, extension control: the maximum stroke L of the extension distance of the previous stage telescopic oil cylinderiLength K ofiWhile gradually reducing the standard extension working flow to the target flow QiFinally with the target flow rate QiExtend to the maximum stroke LiAt least one of (1) and (b); the rear-stage telescopic oil cylinder extends out, and the extending working flow of the rear-stage telescopic oil cylinder is in the extending length K'i-1Gradually increasing within range to target flow Q'i-1；
S200, retraction control: the maximum stroke L of the retraction distance of the previous stage telescopic oil cylinderiLength of (2)
While gradually reducing its standard retract working flow to the target flow
Finally, the target flow rate is used
Retracted to maximum stroke LiAt least one of (1) and (b); the last stage of telescopic oil cylinder retracts, and the retraction working flow of the last stage of telescopic oil cylinder is in the retraction length
Gradually increasing within the range to a target flow
Wherein, i and n are positive integers, i is 2, 3, …, n is not less than 2.
2. The boom extension and retraction control method according to claim 1, wherein the working flow rate of each stage of extension and retraction of the telescopic oil cylinder is changed by controlling the input current of the electro proportional valve.
3. The utility model provides a cantilever crane control system, the cantilever crane includes n section telescopic boom, n level telescopic cylinder, its characterized in that, cantilever crane control system includes:
the detection device (300) is used for detecting the total length L of the cantilever crane in extension;
a control device (400) which is dependent on the maximum travel L when the previous telescopic boom is extendedi、…、Ln-1、LnJudging the maximum stroke L of the extension distance of the current movable telescopic oil cylinder by the L valueiHas a length of KiWhen it is time, the corresponding control command M is issuedi(ii) a When the rear telescopic arm just extends out, the rear telescopic arm is according to the maximum stroke Li、…、Ln-1、LnAnd judging that the retraction length of the current active telescopic oil cylinder is K 'by the L value'i-1When the range is within, a corresponding control command M 'is sent out'i-1(ii) a When the previous telescopic arm is retracted, it is according to the maximum stroke L1、L2、…、Li-1Judging the maximum stroke L of the retracting distance of the current movable telescopic oil cylinder by the L valueiHas a length of
When it is time, the corresponding control command is issued
When the rear telescopic arm just retracts, the rear telescopic arm is according to the maximum stroke L1、L2、…、Li-1Judging the retracting length of the current movable telescopic oil cylinder by the L value
When the range is within, corresponding control command is sent out
An execution device (500), the execution device (500) being in accordance with the control command MiGradually decreasing the current activity extensionReducing the working flow of the oil cylinder to a target flow Qi(ii) a The execution device (500) is used for executing the control command M'i-1Gradually increasing the working flow of the current active telescopic oil cylinder to a target flow Q'i-1(ii) a The execution device (500) executes the control command
Gradually reducing the working flow of the current movable telescopic oil cylinder to a target flow
The execution device (500) executes the control command
Gradually increasing the working flow of the current movable telescopic oil cylinder to the target flow
Wherein, i and n are positive integers, i is 2, 3, …, n is not less than 2.
4. The boom control system according to claim 3, characterized in that the detection means (300) is a length sensor mounted on the boom.
5. An aerial work platform comprising a base frame (600), a turntable (700), an arm support arranged on the turntable (700), characterized by further comprising an arm support control system according to claim 3 or 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011350495.2A CN112520655A (en) | 2020-11-26 | 2020-11-26 | Arm support telescopic control method, arm support control system and aerial work platform |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011350495.2A CN112520655A (en) | 2020-11-26 | 2020-11-26 | Arm support telescopic control method, arm support control system and aerial work platform |
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| Publication Number | Publication Date |
|---|---|
| CN112520655A true CN112520655A (en) | 2021-03-19 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011350495.2A Pending CN112520655A (en) | 2020-11-26 | 2020-11-26 | Arm support telescopic control method, arm support control system and aerial work platform |
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| CN (1) | CN112520655A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20220340403A1 (en) * | 2021-04-26 | 2022-10-27 | Zoomlion Heavy Industry Na, Inc. | Telescoping Jib with An Extended Envelope |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2458503A1 (en) * | 1979-06-12 | 1981-01-02 | Potain Sa | Adjustable height support for maintenance of buildings - has movable forks mounted on carriage on tower and moving up and down tracks under action of winch |
| CN1109842A (en) * | 1993-12-08 | 1995-10-11 | Ec工程咨询特殊机械有限公司 | A telescopic boom with a multistage, lockable hydraulic cylinder protected against buckling |
| CN102637047A (en) * | 2012-04-12 | 2012-08-15 | 中联重科股份有限公司 | Telescopic follow-up control method and system of suspension arm |
| CN203009444U (en) * | 2012-10-31 | 2013-06-19 | 山推楚天工程机械有限公司 | Novel electrical control pumping oil cylinder based on magnetostrictive sensors |
-
2020
- 2020-11-26 CN CN202011350495.2A patent/CN112520655A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2458503A1 (en) * | 1979-06-12 | 1981-01-02 | Potain Sa | Adjustable height support for maintenance of buildings - has movable forks mounted on carriage on tower and moving up and down tracks under action of winch |
| CN1109842A (en) * | 1993-12-08 | 1995-10-11 | Ec工程咨询特殊机械有限公司 | A telescopic boom with a multistage, lockable hydraulic cylinder protected against buckling |
| CN102637047A (en) * | 2012-04-12 | 2012-08-15 | 中联重科股份有限公司 | Telescopic follow-up control method and system of suspension arm |
| CN203009444U (en) * | 2012-10-31 | 2013-06-19 | 山推楚天工程机械有限公司 | Novel electrical control pumping oil cylinder based on magnetostrictive sensors |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20220340403A1 (en) * | 2021-04-26 | 2022-10-27 | Zoomlion Heavy Industry Na, Inc. | Telescoping Jib with An Extended Envelope |
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Application publication date: 20210319 |
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