CN112678699A - Crane and single-cylinder bolt type telescopic control method and system thereof - Google Patents
Crane and single-cylinder bolt type telescopic control method and system thereof Download PDFInfo
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Abstract
The invention discloses a single-cylinder bolt type control method of a crane, which comprises the following processes: the controller acquires the current working condition of the crane in real time and determines whether to enter a rapid stretching mode according to the current working condition; if the current working condition does not allow to enter the rapid extension mode, a first signal is sent out to carry out normal extension; and if the current working condition allows the quick extension mode to be entered, sending a second signal to carry out quick extension. The corresponding control system comprises a balance valve, an arm pin driving mechanism, a cylinder arm pin control valve and a telescopic control valve system, wherein the telescopic control valve system comprises a cartridge valve I, a cartridge valve II, a reversing valve I, a reversing valve II, a shuttle valve, an overflow valve and a one-way valve. The single-cylinder bolt type telescopic control system and the single-cylinder bolt type telescopic control method provided by the invention automatically judge whether to enter a quick extension mode or not according to the current working condition of the crane; the telescopic speed is improved and the operating efficiency of the crane is improved under the condition that the pump displacement is not increased.
Description
Technical Field
The invention relates to a crane and a single-cylinder bolt type telescopic control method and system thereof, belonging to the technical field of engineering machinery.
Background
The crane is an important device widely applied in engineering construction, and mainly comprises basic actions of lifting, stretching, amplitude changing, rotation and the like, the crane stretching mechanism mainly comprises two forms of an oil cylinder rope adding row and a single-cylinder bolt, along with the increase of the tonnage of the crane, the stretching form of the single-cylinder bolt is mostly adopted, namely, the tail end of each stretching arm is provided with a pin shaft which can lock the stretching arm with the stretching arm outside the stretching arm and can move up and down, the pin shaft is arranged on the stretching arm and is called an arm pin, the arm pin is used for realizing the locking and unlocking between the stretching arm and the stretching arm, the initial position of the arm pin can move to an arm pin hole of the other stretching arm under the action of a spring force, so that the stretching arm and the stretching arm can not move mutually to achieve the fixed connection effect, when the arm pin is acted by an arm pin driving mechanism on the stretching oil cylinder, the arm pin retracts from the arm pin hole of the other stretching arm, and the stretching arm can, the purpose of unlocking is achieved. The cylinder pin, the cylinder pin driving mechanism and the boom pin driving mechanism are all arranged on the telescopic oil cylinder, the cylinder pin is in a release state at an initial position under the action of spring force, when the cylinder pin is released in a cylinder pin hole of the boom, locking between the telescopic oil cylinder and the boom is realized, and the boom can be extended or retracted through extension or retraction of the telescopic oil cylinder.
In the prior art, in the boom extending process of a crane, a cylinder pin is inserted firstly to connect a telescopic cylinder with a boom, a boom pin is pulled out later to cancel the connection between the boom and the boom, the telescopic cylinder drives the boom to extend (with the boom extending), when the boom reaches a proper boom position, an boom pin is inserted firstly to connect the boom with the boom, a cylinder pin is pulled out later to cancel the fixed connection between the boom and the telescopic cylinder, then the telescopic cylinder moves to the next boom (empty cylinder retracting), then a cylinder pin is inserted to connect … … between the telescopic cylinder and the boom, and so on, so that the boom extends in one section, in the boom extending process of the crane, the telescopic cylinder finds a proper boom position, the cylinder pin is inserted firstly to fixedly connect the telescopic cylinder with the boom, the boom pin is pulled out later to cancel the fixed connection between the boom and the boom, the telescopic cylinder drives the boom to retract (with the boom retracting), when the boom reaches the proper boom position, the boom pin is inserted firstly to connect the boom with the boom, and pulling out the cylinder pin, canceling the fixed connection between the extending arm and the telescopic cylinder, moving the telescopic cylinder to the next section of arm (extending the empty cylinder), inserting the cylinder pin, fixedly connecting the telescopic cylinder and the extending arm … …, and so on, thereby realizing the retraction of one section of the extending arm and further realizing the telescopic action of the crane.
As shown in fig. 1, oil enters from the port B ' and enters the rodless cavity of the oil cylinder 1 ' through the balance valve 2 ', and oil in the rod cavity of the oil cylinder 1 ' returns through the port a '; the C ' port oil inlet supplies oil for the cylinder arm pin, when the cylinder arm pin control valve 5 ' is not electrified, the C ' port oil inlet acts on the arm pin driving mechanism 3 ' to realize the function of pulling out the arm pin, and when the cylinder arm pin control valve 5 ' is electrified, the C ' port oil inlet acts on the cylinder pin driving mechanism 4 ' to realize the function of pulling out the cylinder pin.
As mentioned above, in the crane telescoping process, the telescopic cylinder mainly has the following four states: the method comprises the following steps of extending an empty cylinder, extending a belt arm, retracting the empty cylinder and retracting the belt arm, taking a single-cylinder bolt six-section arm product as an example, extending a fully-extended arm at least 5 times by using the belt arm and retracting the empty cylinder 4 times; the fully-contracted arm needs to be contracted for at least 5 times with the arm and is expanded for 4 times without the cylinder, namely the fully-expanded and fully-contracted arms need to be expanded for at least 9 times and contracted for 9 times, because the areas of a rodless cavity and a rod cavity of the oil cylinder are greatly different, the flow required by the contracted arm is very small, and the flow required by the expanded arm is very large, so that the expanding speed is low, the contracting speed is high, and a large half of the time is required for the expansion action in the fully-expanded or fully-contracted process.
Along with the increase of the tonnage of a product, the number of sections of the extension arm is increased, the specification size of the telescopic oil cylinder is also increased, the requirement on the flow is also increased greatly, the condition that the flow requirement is much larger than that of a hoisting system is often caused, if the telescopic oil cylinder is designed according to the maximum flow, the cost is increased, the energy is wasted, and the element utilization is insufficient. But the requirement of flexible speed is also very urgent, and single cylinder bolt formula telescopic system is originally lower than the telescopic system efficiency of rope row, if the flow is unsatisfied again, will cause the problem that full flexible time is long, the operating efficiency is low.
Disclosure of Invention
The purpose is as follows: in order to overcome the defects in the prior art, the invention provides a crane and a single-cylinder bolt type telescopic control method and system thereof.
The technical scheme is as follows: in order to solve the technical problems, the technical scheme adopted by the invention is as follows:
a single-cylinder bolt type telescopic control method comprises the following processes,
the controller acquires the current working condition of the crane in real time and determines whether to enter a rapid stretching mode according to the current working condition;
if the current working condition does not allow to enter the rapid extension mode, a first signal is sent out to carry out normal extension;
and if the current working condition allows the quick extension mode to be entered, sending a second signal to carry out quick extension.
Further, if the current working condition is an idle cylinder extension working condition, the controller sends a second signal to rapidly extend.
Further, if the current working condition is a belt arm extension working condition, whether the rapid extension mode is allowed to be entered or not is judged according to working condition parameters, and the judging process is as follows:
the controller reads the current combination of the length of the front arm, the hanging weight and the amplitude variation angle in real time, calculates whether the preset value of the rapid stretching mode is exceeded or not, allows the rapid stretching mode to enter if the preset value is not exceeded, and does not allow the rapid stretching mode to enter if the preset value is exceeded.
Further, the working condition of extending the arm comprises a working condition of extending the main arm independently and a working condition of extending the main arm and the auxiliary arm simultaneously.
A single-cylinder pin type telescopic control system comprises a balance valve, an arm pin driving mechanism, a cylinder pin driving mechanism and a cylinder arm pin control valve, wherein an oil cylinder is provided with three oil ports which are respectively an A port, a B port and a C port; the oil enters from the port B and enters a rodless cavity of the oil cylinder through a balance valve; the telescopic control valve system comprises a cartridge valve I, a cartridge valve II, a reversing valve I, a reversing valve II, a shuttle valve, an overflow valve and a one-way valve;
the left side of the first cartridge valve is connected with the port A, the one-way valve is connected between the port B and the balance valve, the first cartridge valve and the lower part of the second cartridge valve are connected, and then are jointly connected to an oil inlet of a rodless cavity of the telescopic oil cylinder, and meanwhile, the joint of the first cartridge valve and the lower part of the second cartridge valve jointly acts on the left side of the shuttle valve;
the upper end of the first cartridge valve is connected to a right lower oil port of the first reversing valve, the first reversing valve works in a left position under the condition that power is not supplied, a right upper oil port is connected with an oil inlet of an overflow valve, and an oil outlet of the overflow valve is connected with a left upper oil port of the first reversing valve and a right upper oil port of the second reversing valve and connected to an oil tank;
the left upper oil port of the reversing valve II is connected to the shuttle valve, and the right side of the shuttle valve is connected between the cartridge valve II and the one-way valve; and the second reversing valve works in the left position when not powered on, and an oil port at the lower right side of the second reversing valve is connected to the upper part of the second cartridge valve.
Further, in a normal stretching mode, the first reversing valve is electrified, the second reversing valve is not electrified, oil in the port B enters the rodless cavity of the oil cylinder, oil in the rod cavity flows to the port A through the cartridge valve, and the cartridge valve is not communicated with the oil cylinder.
Further, in the fast extension mode, the first reversing valve is electrified, the second reversing valve is electrified, and oil at the port B enters the rodless cavity of the oil cylinder; oil in the rod cavity of the oil cylinder flows to the port B through the cartridge valve II and the one-way valve, and enters the rodless cavity of the oil cylinder together with the oil in the port B, so that the flow of the rodless cavity is increased; oil in the rod cavity of the oil cylinder acts on an oil inlet of the overflow valve through the first cartridge valve.
Furthermore, when the oil cylinder is in a static state, the first reversing valve is not powered, and the second reversing valve is not powered, so that a rodless cavity of the oil cylinder always has certain back pressure, and the phenomenon that the oil cylinder moves forwards when a cylinder arm pin is inserted and pulled is avoided.
A crane comprises the single-cylinder bolt type telescopic control system.
Has the advantages that: the invention provides a single-cylinder bolt type telescopic control system and a single-cylinder bolt type telescopic control method, which automatically judge whether to enter a quick extension mode or not according to the current working condition of a crane; the telescopic speed is improved and the operating efficiency of the crane is improved under the condition that the pump displacement is not increased.
Drawings
FIG. 1 is a schematic diagram of a prior art telescoping control system;
FIG. 2 is a schematic diagram of a telescoping control system according to the present invention.
Detailed Description
The present invention will be further described with reference to the accompanying drawings.
A single-cylinder pin type telescopic control system comprises a balance valve 2, an arm pin driving mechanism 3, a cylinder pin driving mechanism 4 and a cylinder arm pin control valve 5, wherein an oil cylinder is provided with three oil ports which are respectively an A port, a B port and a C port; the port B is filled with oil and enters a rodless cavity of the oil cylinder 1 through the balance valve 2; a rod cavity of the oil cylinder 1 returns oil through an opening A, and an oil inlet of an opening C supplies oil to the cylinder arm pin; the telescopic control valve system comprises a first cartridge valve 6-1, a second cartridge valve 6-2, a first reversing valve 6-3, a second reversing valve 6-4, a shuttle valve 6-5, an overflow valve 6-6 and a one-way valve 6-7, and is shown in figure 2.
The left side of the first cartridge valve 6-1 is connected with the port A, the one-way valve 6-7 is connected between the port B and the balance valve 2, the first cartridge valve 6-1 and the lower part of the second cartridge valve 6-2 are connected and then are jointly connected to an oil inlet of a rodless cavity of the oil cylinder, and meanwhile, the joint of the first cartridge valve 6-1 and the lower part of the second cartridge valve 6-2 jointly acts on the left side of the shuttle valve 6-5;
the upper end of the cartridge valve I6-1 is connected to a right lower oil port of the reversing valve I6-3, the reversing valve I6-3 works at a left position under the condition of no power supply, a right upper oil port is connected with an oil inlet of the overflow valve 6-6, and an oil outlet of the overflow valve 6-6 is connected with the left upper oil port of the reversing valve I6-3 and a right upper oil port of the reversing valve II 6-4 together and is connected to an oil tank;
the left upper oil port of the second reversing valve 6-4 is connected to the shuttle valve 6-5, and the right side of the shuttle valve 6-5 is connected between the cartridge valve 6-2 and the one-way valve 6-7; the second reversing valve 6-4 works in the left position when not powered, and the oil port at the lower right is connected to the upper part of the second cartridge valve 6-2.
A single-cylinder bolt type telescopic control method comprises the following processes:
the controller acquires the current working condition of the crane in real time and determines whether to enter a rapid stretching mode according to the current working condition;
if the current working condition is a working condition of extending the empty cylinder, allowing to enter a rapid extending mode, and sending a second signal by the controller to perform rapid extending;
if the current working condition is the working condition with arm extension, whether the rapid extension mode is allowed to be entered or not is judged according to working condition parameters, and the judging process is as follows:
the controller reads the current forearm length combination, the hanging weight and the amplitude variation angle in real time, calculates whether the preset value of the rapid stretching mode is exceeded or not, allows the rapid stretching mode to enter if the preset value is not exceeded, and sends a second signal to rapidly stretch out; if the preset value is exceeded, the quick stretching mode is not allowed to enter, and the controller sends a first signal to carry out normal stretching.
The working condition of the extension with the arm comprises a working condition of independently extending the main arm and a working condition of simultaneously extending the main arm and the auxiliary arm.
Under the normal stretching mode, the first reversing valve 6-3 is electrified, the second reversing valve 6-4 is not electrified, oil at the port B enters the rodless cavity of the oil cylinder, the oil cannot flow to the telescopic control valve system due to the one-way valve 6-7, the oil at the rod cavity flows to the port A through the first cartridge valve 6-1, and the second cartridge valve 6-2 is not communicated, so the oil at the port A cannot flow to the port B.
Under the fast extension mode, the first reversing valve 6-3 is electrified, the second reversing valve 6-4 is electrified, and the oil at the port B enters the rodless cavity of the oil cylinder; oil in the rod cavity of the oil cylinder flows to the port B through the cartridge valve II 6-2 and the one-way valve 6-7 and enters the rodless cavity of the oil cylinder together with the oil in the port B, so that the flow of the rodless cavity is increased; oil in a rod cavity of the oil cylinder acts on an oil inlet of the overflow valve 6-6 through the cartridge valve I6-1. The set value of the overflow valve 6-6 is slightly higher than the highest pressure (the highest pressure is limited by a secondary overflow valve which is arranged in front of the port B and is not shown in figure 2), so that when the oil cylinder extends out, oil in the rod cavity can enter the rodless cavity, the flow of the rodless cavity is improved, the operation speed of the oil cylinder is increased, when the pressure is higher than the highest pressure, the overflow valve 6-6 overflows, the cartridge valve I6-1 is opened, the oil in the rodless cavity can return to the port A through the cartridge valve I6-1, and the working safety of the oil cylinder is ensured.
When the oil cylinder is in a static state, namely, the oil cylinder does not extend or contract, the first reversing valve 6-3 and the second reversing valve 6-4 are not powered, so that the rodless cavity always has certain back pressure, and the phenomenon that the telescopic oil cylinder moves forwards when the cylinder arm pin is plugged and pulled is avoided.
The utility model provides a hoist, stretches out the mode through its hydro-cylinder of aforementioned single cylinder bolt formula telescopic control system control, stretches out fast under the condition that the operating mode allows, improves hoist operating efficiency.
The above description is only of the preferred embodiments of the present invention, and it should be noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the invention and these are intended to be within the scope of the invention.
Claims (10)
1. A single-cylinder bolt type telescopic control method is characterized by comprising the following steps: comprises the following steps of,
the controller acquires the current working condition of the crane in real time and determines whether to enter a rapid stretching mode according to the current working condition;
if the current working condition does not allow to enter the rapid extension mode, a first signal is sent out to carry out normal extension;
and if the current working condition allows the quick extension mode to be entered, sending a second signal to carry out quick extension.
2. The single-cylinder bolt type telescopic control method of claim 1, wherein: and if the current working condition is an idle cylinder stretching working condition, the controller sends a second signal to rapidly stretch out.
3. The single-cylinder bolt type telescopic control method of claim 2, wherein: if the current working condition is the working condition with arm extension, whether the rapid extension mode is allowed to be entered or not is judged according to working condition parameters.
4. A single cylinder pin extension and retraction control method as claimed in claim 3, wherein: under the working condition that the belt arm extends, the judgment process of whether the belt arm is allowed to enter the quick extension mode is as follows:
the controller reads the current combination of the length of the front arm, the hanging weight and the amplitude variation angle in real time, calculates whether the preset value of the rapid stretching mode is exceeded or not, allows the rapid stretching mode to enter if the preset value is not exceeded, and does not allow the rapid stretching mode to enter if the preset value is exceeded.
5. A single cylinder pin extension and retraction control method as claimed in claim 3, wherein: the working condition of the extension with the arm comprises a working condition of independently extending the main arm and a working condition of simultaneously extending the main arm and the auxiliary arm.
6. A single-cylinder pin type telescopic control system comprises a balance valve (2), an arm pin driving mechanism (3), a cylinder pin driving mechanism (4) and a cylinder arm pin control valve (5), wherein an oil cylinder is provided with three oil ports which are respectively an A port, a B port and a C port; the port B is filled with oil and enters a rodless cavity of the oil cylinder (1) through the balance valve (2); the pole chamber of hydro-cylinder (1) passes through A mouth oil return, and C mouth oil feed is jar arm round pin fuel feeding, its characterized in that: the telescopic control valve system comprises a first cartridge valve (6-1), a second cartridge valve (6-2), a first reversing valve (6-3), a second reversing valve (6-4), a shuttle valve (6-5), an overflow valve (6-6) and a one-way valve (6-7);
the left side of the first cartridge valve (6-1) is connected with the port A, the one-way valve (6-7) is connected between the port B and the balance valve (2), the first cartridge valve (6-1) is connected with the lower part of the second cartridge valve (6-2), then the first cartridge valve (6-1) and the second cartridge valve (6-2) are connected with each other and are connected with an oil inlet of a rodless cavity of an oil cylinder together, and meanwhile, the connecting part of the first cartridge valve (6-1) and the lower part of the second cartridge valve (6-2) acts on the left side of;
the upper end of the cartridge valve I (6-1) is connected to a right lower oil port of the reversing valve I (6-3), the reversing valve I (6-3) works at a left position under the condition of no power supply, a right upper oil port is connected with an oil inlet of the overflow valve (6-6), and an oil outlet of the overflow valve (6-6) is connected with the left upper oil port of the reversing valve I (6-3) and a right upper oil port of the reversing valve II (6-4) together and is connected to an oil tank;
the left upper oil port of the second reversing valve (6-4) is connected to the shuttle valve (6-5), and the right side of the shuttle valve (6-5) is connected between the second cartridge valve (6-2) and the one-way valve (6-7); the second reversing valve (6-4) works at the left position when not powered on, and the oil port at the lower right is connected to the upper part of the second cartridge valve (6-2).
7. The single cylinder bolt extension control system of claim 6, wherein: under a normal extension mode, the first reversing valve (6-3) is electrified, the second reversing valve (6-4) is not electrified, oil at the port B enters the rodless cavity of the oil cylinder, oil in the rod cavity flows to the port A through the first cartridge valve (6-1), and the second cartridge valve (6-2) is not communicated.
8. The single cylinder bolt extension control system of claim 6, wherein: in the fast extension mode, the first reversing valve (6-3) is electrified, the second reversing valve (6-4) is electrified, and the oil at the port B enters the rodless cavity of the oil cylinder; oil in the rod cavity of the oil cylinder flows to the port B through the cartridge valve II (6-2) and the one-way valve (6-7), and enters the rodless cavity of the oil cylinder together with the oil in the port B, so that the flow of the rodless cavity is increased; oil in a rod cavity of the oil cylinder acts on an oil inlet of the overflow valve (6-6) through the cartridge valve I (6-1).
9. The single cylinder bolt extension control system of claim 6, wherein: when the oil cylinder is in a static state, the first reversing valve (6-3) is not powered, and the second reversing valve (6-4) is not powered, so that a rodless cavity of the oil cylinder always has certain back pressure, and the phenomenon that the oil cylinder moves forwards when a cylinder arm pin is inserted and pulled is avoided.
10. A crane comprising a single cylinder pin telescoping control system as claimed in any one of claims 6 to 9.
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Cited By (2)
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CN113896121A (en) * | 2021-10-08 | 2022-01-07 | 徐州重型机械有限公司 | Crane bolt type telescopic system and crane |
CN114412853A (en) * | 2021-12-31 | 2022-04-29 | 徐州重型机械有限公司 | Double-cylinder-head telescopic system and control method |
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CN104528548A (en) * | 2014-12-12 | 2015-04-22 | 中联重科股份有限公司 | Calibration system and calibration method for telescopic speed of suspension arm |
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CN202245776U (en) * | 2011-08-11 | 2012-05-30 | 三一汽车起重机械有限公司 | Oil cylinder telescoping control device, elevator boom and hoisting machinery |
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Publication number | Priority date | Publication date | Assignee | Title |
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CN113896121A (en) * | 2021-10-08 | 2022-01-07 | 徐州重型机械有限公司 | Crane bolt type telescopic system and crane |
CN114412853A (en) * | 2021-12-31 | 2022-04-29 | 徐州重型机械有限公司 | Double-cylinder-head telescopic system and control method |
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