WO2012155747A1

WO2012155747A1 - Telescopic boom and engineering machine comprising the same

Info

Publication number: WO2012155747A1
Application number: PCT/CN2012/074208
Authority: WO
Inventors: 李丰; 周斌; 曾少林
Original assignee: 湖南三一智能控制设备有限公司; 三一汽车起重机械有限公司
Priority date: 2011-05-18
Filing date: 2012-04-17
Publication date: 2012-11-22
Also published as: CN102259802A; CN102259802B

Abstract

Disclosed in the present invention are a telescopic boom and an engineering machine comprising the same. The telescopic boom comprises a telescopic cylinder (200), a multi-arm and a hydraulic system. The free end (201) of said telescopic cylinder (200) extends and contracts in an the extending direction of the telescopic boom, and said hydraulic system is connectted with the telescopic cylinder (200) through a hydraulic oil way. The telescopic boom also comprises at least one mechanical stop mechanism cooperated with the free end (201) of telescopic cylinder (200),and it also comprises a control device (400) and a position sensor corresponded with the mechanical stop mechanism. The said position sensor are used for detecting position of the free end (201) of the telescopic cylinder, the control device (400) outputs control signal to the proportional control valve (500) based on a predetermined strategy, reducing the speed of the free end of the telescopic cylinder(201). By using the technicalsolution, based on control signal, it reduces the speed of the telescopic cylinder (200), the speed reduces to a lower value or just stop at a position corresponding with mechanical stop mechanism when the free end (201) of the telescopic cylinder reach the corresponding mechanical stop mechanism, this can reduce or avoid the impact between free end (201) and mechanical stop mechanism.

Description

The invention relates to a telescopic arm and a construction machine including the same, which is submitted to the Chinese Patent Office on May 18, 2011, and the application number is 201110131108.0, and the invention name is "a telescopic arm and a construction machine including the telescopic arm," Priority of the Chinese Patent Application, the entire contents of which is incorporated herein by reference.

Technical field

The invention relates to a telescopic control technology, in particular to a telescopic arm, and to a construction machine including the telescopic arm.

Background technique

Please refer to Fig. 1, which is a schematic diagram of the working principle of the telescopic arm disclosed in Chinese Patent Publication No. CN101585491A. The telescopic arm includes a latch connecting portion, a cord connecting portion, and a telescopic cylinder 200 located in the telescopic arm distal arm. The latch connecting portion includes a base arm 110 and two arms 120 located in the base arm 110; the cord connecting portion includes a three-arm 1 30, a four-arm 140, and a five-arm 150 that are sequentially assembled together from the outside to the inside; wherein, the three-arm 1 The 30 sets are placed within the two arms 120; the three arms 1 30, the four arms 140 and the five arms 150 are connected by a rope formed by a runner and a cable. The cylinder 210 of the telescopic cylinder 200 is fixed to the three arms 1 30 to form a fixed end of the telescopic cylinder 200. The outer end of the cylinder rod 220 forms the movable end 201 of the telescopic cylinder 200; the movable end 201 can be fixed to the base arm 1 10 or Fixed with two arms 120. When the movable end 201 is fixed to the base arm 1 10, the telescopic cylinder 200 can expand and contract to extend and contract the two arms 120 relative to the base arm 110; when the movable end 201 is fixed to the two arms 120, the telescopic cylinder 200 can be extended and contracted to make the three arms 130; The four arms 140 and the five arms 150 are synchronized with respect to the two arms 120. A detailed working principle can be found in Chinese Patent Document CN101585491 A.

In order to realize the expansion and contraction of the telescopic arm, the movable end 201 needs to be converted between the arm tail of the base arm 110 and the arm tail of the two arms 120; in order to ensure that the movable end 201 and the predetermined pitch arm are smoothly and reliably fixed, the base arm 110 is The arm tail and the arm tail of the two arms 120 are respectively provided with a mechanical limiting mechanism 11 1 and a mechanical limiting mechanism 121. When the movable end 201 reaches the arm tail of the two arms 120 from the arm tail of the base arm 110, the mechanical limiting mechanism 121 can limit the movable end 201 so that the movable end 201 and the arm tail of the two arm 120 are fixed by the cylinder pin. Similarly, when the movable end 201 reaches the arm tail of the base arm 110 from the arm tail of the two arms 120, the mechanical limiting mechanism 11 1 can limit the movable end 201 to restrict the movement of the movable end 201, so that the movable end 201 and the base arm The end of the 11 0 arm is fixed by the cylinder pin.

Thus, the movable end 201 of the telescopic cylinder 200 is mainly dependent on the mechanical limit mechanism. When the movable end 201 reaches the position of the mechanical limit mechanism, it is easy to collide with the mechanical limit mechanism. Sexual impact; long-term collision impact will cause deformation of the mechanical limit mechanism, affecting the accurate positioning of the cylinder rod 220; in severe cases, it will also cause damage to the mechanical limit mechanism and the telescopic cylinder. Severe collisional impacts can also loosen the arm pins between the arms, causing a safety hazard.

Therefore, how to reduce the impact of the expansion and contraction of the movable end of the telescopic cylinder on the mechanical limit mechanism is a technical problem that a person skilled in the art needs to solve. This technical problem exists not only in the telescopic arm described above, but also in other telescopic arms having mechanical limit mechanisms.

Summary of the invention

Accordingly, it is an object of the present invention to provide a telescopic arm that includes a mechanical limit mechanism for limiting the movable end of the telescopic cylinder, the telescopic arm capable of reducing the telescopic to mechanical limit mechanism of the telescopic cylinder The resulting collision impact.

In addition to providing the telescopic arm described above, the present invention also provides an engineering machine including the telescopic arm, which can be a crane, a crane or other construction machine.

In order to achieve the above object, the telescopic arm provided by the present invention comprises a telescopic cylinder, a multi-joint arm and a hydraulic system, the movable end of the telescopic cylinder is telescoped in the extending direction of the telescopic arm, and the hydraulic system is connected to the telescopic cylinder through a hydraulic oil passage. And a controller, a proportional control valve and at least one position sensor; the position sensor corresponding to the mechanical limit mechanism for detecting the position of the movable end The proportional control valve is connected to a hydraulic oil line between the hydraulic system and the telescopic cylinder; the controller determines a distance between the movable end and the mechanical limit mechanism according to the detection signal of the position sensor, and according to a predetermined control The controller outputs a control signal to the proportional control valve; the proportional control valve controls a moving speed of the movable end according to the control signal; the control strategy includes: when the distance between the movable end and the mechanical limiting mechanism is a predetermined value, Reduce the speed of movement of the active end.

In an optional technical solution, the telescopic cylinder includes a first position sensor and a second position sensor sequentially arranged along a telescopic direction of the telescopic cylinder, corresponding to the mechanical limit mechanism; the controller is detected according to the first position sensor The signal determines a first distance between the active end and the mechanical limit mechanism, and outputs a first control signal to the proportional control valve according to a predetermined control strategy; and further determines an active end according to the detection signal of the second position sensor Determining a second distance between the mechanical limiting mechanisms, and outputting a second control signal to the proportional control valve according to a predetermined control strategy; the proportional control valve respectively causing the active end according to the first control signal and the second control signal a first speed and a second speed; the first distance is greater than the second distance; the first speed is greater than the second speed Degree.

Optionally, the controller is connected to an operating mechanism that controls expansion and contraction of the telescopic cylinder, and determines a motion state of the telescopic cylinder according to a state of the operating mechanism; the control strategy includes: at the active end and the mechanical limiting mechanism The distance between the movable ends is reduced when the distance between the movable ends is a predetermined value and the movable end moves toward the mechanical limit mechanism.

Optionally, the telescopic arm includes at least two position sensors sequentially arranged in a telescopic direction of the telescopic cylinder and corresponding to the mechanical limit mechanism; and the control strategy of the controller according to the detection of the position sensor comprises: When the distance between the mechanical limit mechanism and the mechanical limit mechanism is a predetermined value, and the movable end moves in a direction close to the mechanical limit mechanism, the moving speed of the movable end is lowered.

Optionally, the telescopic arm includes at least two position sensors sequentially arranged along the telescopic direction of the telescopic cylinder and corresponding to the mechanical limit mechanism; the controller determines the moving speed of the movable end according to the time difference generated by the detection signal of the position sensor. The control strategy includes: when the distance between the active end and the mechanical limit mechanism is a predetermined value, and the moving speed of the movable end is greater than a predetermined value, causing the movable end to move at a predetermined first speed; The distance between the mechanical limiting mechanisms is a predetermined value, and when the moving speed of the movable end is less than a predetermined value, the movable end is moved at a predetermined second speed; the first speed is greater than the second speed.

Optionally, the controller determines a moving direction of the active end relative to the mechanical limiting mechanism according to a sequence of detection signals generated by the position sensor; the control strategy includes: at the active end and the mechanical limit The distance between the mechanisms is a predetermined value, and when the movable end moves in a direction close to the mechanical limit mechanism, the moving speed of the movable end is lowered.

Optionally, the control strategy includes: when the distance between the active end and the mechanical limiting mechanism is a predetermined value, and the moving end moves in a direction away from the mechanical limiting mechanism, increasing the moving speed of the movable end Force mouth.

Optionally, the position sensor is a proximity switch.

Optionally, the base arm of the multi-section arm and the at least one arm in the base arm form a bolt connection portion; at least two joint arms located inside the plug connection portion form a rope row connection portion; the fixed end of the telescopic cylinder is The outermost joint arms of the cord connecting portion are fixed, and the movable end is selectively connected to any of the joint arms of the plug connecting portion; and each of the joint arms of the plug connecting portion is provided with the mechanical limiting mechanism. The construction machine provided by the present invention comprises a chassis and a telescopic arm, and the telescopic arm is rotatably connected to the chassis through a lateral hinge shaft, and the telescopic arm is any one of the above-mentioned telescopic arms.

The telescopic arm provided by the invention includes a control system including a position sensor and a controller and a proportional control valve, in addition to a multi-joint arm, a telescopic cylinder and a mechanical limit mechanism; the position sensor and the mechanical limit Corresponding to the mechanism, for detecting the position of the movable end of the telescopic cylinder; when the movable end reaches the predetermined position, the position sensor generates a corresponding detection signal; the controller is capable of determining the movable end and the mechanical device according to the detection signal of the position sensor a distance between the limiting mechanisms, and outputting a control signal to the proportional control valve according to a predetermined control strategy; the proportional control valve controls a moving speed of the movable end according to the control signal; the control strategy includes: When the distance between the mechanical limiting mechanisms is a predetermined value, the moving speed of the movable end is lowered, and the telescopic speed of the telescopic cylinder is reduced, so that the speed is reduced to one when the movable end reaches the corresponding mechanical limiting mechanism. Lower value, or just stop at the position corresponding to the mechanical limit mechanism, so You may reduce or avoid a collision of the impact between the movable end of the mechanical stops. The proportional control valve can be used to control the telescopic speed of the telescopic cylinder, which can automatically control the telescopic speed of the telescopic cylinder. It can not only improve the accuracy of the telescopic arm, but also improve the intelligence of the control system and make the control operation of the telescopic arm more convenient.

In a further technical solution, the controller is connected to an operating mechanism for controlling the expansion and contraction of the telescopic cylinder, and can determine the motion state of the telescopic cylinder according to the state of the operating mechanism; when it is determined that the movable end is moving toward the mechanical limiting mechanism, It is necessary to reduce the speed of the movable end to reduce or avoid the impact impact between the movable end and the mechanical limit mechanism. Further, the controller can output a predetermined control signal according to the motion state of the extension cylinder and the detection signal and the predetermined control strategy; thus, the control system can automatically recognize the motion state of the movable end of the telescopic cylinder and improve the accuracy of the control.

In a further technical solution, the telescopic arm includes at least two position sensors sequentially arranged in the telescopic direction of the telescopic cylinder, so that the controller can determine the moving direction of the movable end according to the sequence of the detection signals generated by the different position sensors; Then, according to the moving direction of the active end and the detection signal of the corresponding position sensor, the control signal is output; thus, the control system can automatically recognize the moving direction of the active end and improve the accuracy of the control.

In a further technical solution, the telescopic arm includes at least two position sensors sequentially arranged along the telescopic cylinder expansion and contraction direction; in the case where the distance between the two position sensors is determined, according to the two The time difference between the detection signals of the position sensors, the controller can determine the moving speed of the movable end, and then can output the control signal according to the moving speed of the moving end and the detection signal of the corresponding position sensor and the predetermined control strategy, so that the telescopic cylinder moves at the corresponding speed. The active end is decelerated at an appropriate acceleration; thus, the control system can adjust the telescopic speed of the telescopic cylinder according to the moving speed of the movable end, and better control the moving speed when the movable end reaches the corresponding mechanical limit mechanism, which is better. Groundly reduce the impact impact between the movable end and the mechanical limit mechanism.

In a further technical solution, the distance between the movable end and the mechanical limit mechanism is a predetermined value, and when the movable end moves away from the mechanical limit mechanism, the moving speed of the movable end is increased. This can increase the operating efficiency of the telescopic arm and improve the construction efficiency of the construction machine.

Since the above-described telescopic arm has the above-described technical effects, the construction machine such as a crane including the above-described telescopic arm provided by the present invention also has a corresponding technical effect.

DRAWINGS

1 is a schematic view showing the working principle of the telescopic arm disclosed in the Chinese patent document CN101585491A; FIG. 2 is a schematic view showing the working principle of the telescopic arm provided by the present invention in a state; FIG. 3 is a schematic view of the telescopic arm provided by the present invention in another state; Figure 4 is a block diagram showing the structure of the control system in the telescopic arm provided by the present invention;

Figure 5 is a control flow chart of the control system in the telescopic arm provided by the present invention.

detailed description

The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings, and the description of the embodiments of the present invention. The description of the present invention is merely exemplary and explanatory, and should not be construed as a Content restrictions.

Please refer to FIG. 2, FIG. 3 and FIG. 4. FIG. 2 is a schematic diagram showing the working principle of the telescopic arm provided by the present invention in one state, and FIG. 3 is a schematic view showing the working principle of the telescopic arm provided by the present invention in another state; Figure 4 is a block diagram showing the structure of the control system in the telescopic boom.

The telescopic arm provided by the present invention comprises five pitch arms, one telescopic cylinder 200 and a corresponding hydraulic system (not shown); the five pitch arms are a base arm 11 0, two arms 120, three arms 1 30, four The connection relationship between the arm 140 and the five arms 150; the five pitch arms is the same as described in the background art, and the base arm 110 and the two arms 120 form a pin connection portion, and the three arms 1 30, the four arms 140 and the five arms 150 are formed. Rope row connection section. The fixed end of the telescopic cylinder 200 is fixed to the three arms 130, and the movable end 201 can extend in the telescopic direction of the telescopic arm with respect to the fixed end, and the hydraulic system passes through the hydraulic oil passage and the telescopic cylinder. 200 is connected to supply hydraulic oil to the telescopic cylinder, and the telescopic cylinder 200 is driven to expand and contract. A mechanical limit mechanism 111 and a mechanical limit mechanism 121 are respectively disposed at a tail end of the base arm 110 and a tail end of the two arms 120. When the movable end 201 extends to the trailing end of the base arm 110, the mechanical limiting mechanism 11 1 can limit the position of the movable end 201, and the movable end 201 can be fixedly connected to the mechanical limiting mechanism 11 1 through the existing latching device; When the telescopic cylinder 2 is telescopic, the two arms 120 can be extended or retracted relative to the base arm 110. When the movable end 201 is retracted to the rear end of the two arms 120, the mechanical limiting mechanism 121 can limit the position of the movable end 201, and the movable end 201 can be fixedly connected to the mechanical limiting mechanism 121 through the latching device; When the cylinder 200 is telescopic, the three arms 1 30, the four arms 140, and the five arms 150 can be simultaneously extended or retracted relative to the two arms 120.

Additionally, the telescopic arm provided by the present invention further includes a control system including a position sensor 310, a position sensor 320, a controller 400, and a proportional control valve 500.

Wherein, the position sensor 310 is installed at a predetermined position, corresponding to the mechanical limit mechanism 111, for detecting the position of the movable end 201; when the distance between the movable end 201 and the mechanical limit mechanism 111 is a predetermined value, correspondingly occurs The detection signal is also installed at a predetermined position corresponding to the mechanical limiting mechanism 121 for detecting the position of the movable end 201. Similarly, the distance between the movable end 201 and the mechanical limiting mechanism 121 is predetermined. When the value is generated, a corresponding detection signal is generated. In this example, position sensor 310 and position sensor 320 are both proximity switches. In the position sensor 301, the detecting head 311 and the sensing block 312 of the proximity switch are respectively fixed to the movable end 201 and the mechanical limiting mechanism 111, and the detecting head 311 moves with the movable end 201, and enters the detecting range of the detecting head 311 at the sensing block 312. In the meantime, the distance between the movable end 201 and the mechanical limit mechanism 111 is a predetermined value (the predetermined value may be a range), and at this time, the detecting head 311 can generate a detection signal of the switching amount. Similarly, in the position sensor 320, the detecting head 321 and the sensing block 322 of the proximity switch are respectively fixed to the movable end 201 and the mechanical limiting mechanism 121; the detecting head 321 and the detecting head 311 are respectively mounted on both sides of the movable end 201, and simultaneously with the activity. When the sensing block 322 enters the detection range of the detecting head 321 , the distance between the movable end 201 and the mechanical limiting mechanism 121 is a predetermined value. At this time, the detecting head 321 can generate a detection signal of the switching amount. .

The proximity switch or other position sensor is not limited to the above-described manner, and the position sensor may be mounted on the cylinder 210 and/or the cylinder rod 210 of the telescopic cylinder 200 or other suitable position as long as the position of the movable end 201 can be detected. Further, the controller 400 can be based on the detection signal The object of the present invention can be achieved by determining the distance between the movable end 201 and the corresponding mechanical limit mechanism. The position sensor corresponds to the mechanical limit mechanism, which means that there is a correspondence between the position sensor and the mechanical limit mechanism, so that the control system can detect the position of the movable end 201 according to the position sensor, and then determine the movable end 201 and the corresponding end. The distance between mechanical limit mechanisms. In this example, there are two mechanical limit mechanisms, and at the same time at least two position sensors are provided.

In this example, both position sensors 31 0 and 320 are coupled to the input of controller 400. The output of controller 400 is coupled to proportional control valve 500. The proportional control valve 500 is connected to the hydraulic oil line between the hydraulic system and the telescopic cylinder 200; the change of the opening degree of the proportional control valve 500 can adjust the flow rate of the hydraulic oil supplied from the hydraulic source to the telescopic cylinder 200, thereby changing the expansion and contraction of the telescopic cylinder 200. speed.

The control principle of the control system is: when the position sensor 31 0 can generate the detection signal, the distance between the movable end 201 and the mechanical limit mechanism 1 1 1 is within a predetermined range; at this time, the controller 400 can be based on the position sensor The detection signal of 31 0 determines the distance between the movable end 201 and the mechanical limit mechanism 1 1 1 , and outputs a corresponding control signal to the proportional control valve 500 according to a predetermined control strategy. The proportional control valve 500 changes its opening degree in accordance with the control signal, and further changes the flow cross section of the oil passage for supplying the hydraulic oil to the telescopic cylinder 200. The control signal may specifically be a current, and the proportional control valve 500 is varied in opening degree by changing the magnitude of the input current to the proportional control valve 500.

The predetermined control strategy may be: as shown in FIG. 2, when the position sensor 31 0 generates and outputs a detection signal, and the controller 400 determines that the distance between the movable end 201 and the mechanical limit mechanism 1 1 1 is a predetermined value L1, this The controller 400 outputs a deceleration control signal to the proportional control valve 5 00, and the proportional control valve 500 reduces the opening degree according to the deceleration control signal, so that the moving speed of the movable end 201 is lowered to reach the mechanical limit mechanism 1 at the movable end 201. At 1 1 hour, the speed is small or just stops moving, and the collision impact between the movable end 201 and the mechanical limit mechanism 11 1 is reduced or avoided. As shown in FIG. 3, when the position sensor 320 generates and outputs a detection signal, and the controller 400 determines that the distance between the movable end 201 and the mechanical limit mechanism 121 is a predetermined value L2, the controller 400 can now switch to the proportional control valve 500. The deceleration control signal is output, and the proportional control valve 500 reduces the opening degree according to the deceleration control signal, reduces the retracting speed of the telescopic cylinder 200, and reduces the moving speed of the movable end 201 to reach the mechanical limiting mechanism 121 at the movable end 201. At this time, the speed is small or just stops the movement, and the collision impact between the movable end 201 and the mechanical limit mechanism 121 is reduced or avoided. The control strategy of the controller 500 can be selected according to actual needs; for example, there can be a corresponding delay between the time at which the position sensor 310 generates the detection signal and the time at which the corresponding control signal is output, and the like. The predetermined values L1 and L2 may be determined according to the telescopic length of the telescopic cylinder 200, the relevant parameters of the hydraulic system, and the operation requirements of the telescopic boom.

Referring to FIG. 2, in the state shown in the figure, when the telescopic cylinder 200 is retracted, the movable end 201 moves to a position away from the mechanical limit mechanism 111. At this time, even if the position sensor 310 generates a detection signal, there is no need to reduce the expansion and contraction. The retracting speed of the cylinder 200; in this case, the telescopic cylinder 200 can be held at a retracting speed by an operating mechanism such as an operating handle that controls the movement of the telescopic cylinder 200, and the telescopic cylinder 200 can be retracted by automatic detection. speed.

Please refer to FIG. 4. In this example, the telescopic arm includes an operating mechanism for controlling the expansion and contraction of the telescopic cylinder 200.

600 is connected, the telescopic cylinder 200 can be controlled by the operating mechanism 600; the input end of the controller 400 is connected to the operating mechanism 600, and the movement state of the telescopic cylinder 200 can be determined according to the state of the operating mechanism 600; The device 400 can output a control signal in conjunction with the motion state of the telescopic cylinder 200 and the detection signal of the position sensor 310, or output a control signal in conjunction with the motion state of the telescopic cylinder 200 and the detection signal of the position sensor 320.

The controller 400 processes the signal according to a certain period. For the processing procedure, please refer to FIG. 5. FIG. 5 is a control flow chart of the control system provided in the telescopic arm of the present invention.

Step S51 Q, the controller 4QQ is activated to cause the controller 4QQ to perform signal scanning at a predetermined cycle. Step S520: The controller 400 determines whether there is a detection signal generated by the position sensor according to the scan result; if yes, the process goes to step S530; if not, the cycle ends, and the scan work of the next work cycle is prepared.

Step S530, the controller 400 determines the distance between the movable end 201 and the mechanical limit mechanism 111, and further determines whether the movable end 201 is close to the mechanical limit mechanism 111 of the base arm 110; if yes, the side proceeds to step S540; if not, then Go to step S560.

Step S540, the controller 400 determines the motion state of the telescopic cylinder 200 according to the state of the operating mechanism 600, and further determines whether the telescopic cylinder 200 is elongated; if yes, proceeds to step S550, and outputs a control signal to the proportional control valve 500 to cause the telescopic cylinder The extension speed of 200 is lowered, and then enters the next duty cycle; if not, the duty cycle ends, directly enters the next duty cycle, and the control signal is no longer output.

Step S560, the controller 400 determines the motion state of the telescopic cylinder 200, and further determines the telescopic cylinder. 200 is elongating, if not, then proceeds to step S570, outputs a control signal to the proportional control valve 500, causes the retracting cylinder 200 to retract the speed, and then enters the next duty cycle; if YES, the duty cycle ends. Go directly to the next work cycle.

The motion state of the telescopic cylinder 200 is not limited to the moving direction of the movable end 201, but may be the moving speed of the movable end 201. The specific manner in which the controller 400 determines the motion state of the telescopic cylinder 200 can determine the state of the operating mechanism 600 by detecting the position and angle of the joystick or the joystick in the operating mechanism 600 by setting the corresponding sensor, thereby determining the moving direction of the movable end 201 and Movement speed.

According to actual needs, an appropriate program can be predetermined in the controller 400 to enable the controller 400 to output a predetermined control signal in accordance with a predetermined control strategy. For example, in the case of controlling the moving speed of the movable end 201 relative to the mechanical limiting mechanism 111, the control strategy may at least include the first of the following manners, when the controller 400 determines that the movable end 201 moves in a direction away from the mechanical limiting mechanism 111, When it is determined that the distance between the movable end 201 and the mechanical limit mechanism 111 is a predetermined value L1, the controller 400 does not output a control signal to the proportional control valve 500, so that the opening degree of the proportional control valve 500 remains unchanged, so that the telescopic cylinder 200 is made The retraction speed remains the same.

Second, when the controller 400 determines that the movable end 201 moves in a direction away from the mechanical limit mechanism 111, and determines that the distance between the movable end 201 and the mechanical limit mechanism 111 is a predetermined value L1, the controller 400 proportionally controls The valve 500 outputs a control signal to increase the opening degree of the proportional control valve 500, so that the telescopic cylinder 200 is retracted at a greater speed, and the moving speed of the movable end 201 is increased to improve the expansion and contraction efficiency of the telescopic arm.

Third, when the controller 400 determines that the movable end 201 moves toward the direction close to the mechanical limit mechanism 111, and determines that the distance between the movable end 201 and the mechanical limit mechanism 111 is a predetermined value L1, the controller 400 proportionally controls The valve 500 outputs a control signal to decrease the opening degree of the proportional control valve 500, so that the moving speed of the movable end 201 is lowered.

Third, when the distance between the movable end 201 and the mechanical limiting mechanism 111 is a predetermined value L1, and the moving speed of the movable end 201 is greater than a predetermined value, the moving speed of the movable end 201 is decreased, and the predetermined speed is made a first speed motion; when the distance between the movable end 201 and the mechanical limiting mechanism is a predetermined value, and the moving speed of the movable end 201 is less than the predetermined value, the moving speed of the movable end 201 is decreased, and a predetermined second speed motion, and causing the first speed to be greater than the second speed Degree.

It can be understood that determining the direction of motion and the speed of movement of the movable end 201 are not limited to being determined by the steering mechanism 600, but can also be determined by setting a plurality of position sensors. For example: at least two position sensors corresponding to the mechanical limit mechanism 111 may be sequentially arranged in the telescopic direction of the telescopic cylinder 200; the position of the movable end 201 is determined when the detection signal is generated due to the position sensor installation position determination; The moving direction of the movable end 201 relative to the mechanical limiting mechanism 111 can be determined according to the sequence of the detection signals generated by the two or more position sensors; thereby determining the moving direction of the movable end 201; and controlling the proportional control valve according to the corresponding control strategy described above. The opening of 500.

It can be understood that, in the case where the two position sensor mounting positions are determined, the movable end 201 relative to the mechanical limit can also be obtained according to the time difference between the detection signals generated by the two position sensors and the distance between the two position sensor mounting positions. The movement speed of the position mechanism 1 11; and the opening degree of the proportional control valve 500 is controlled according to the above corresponding control strategy.

The control strategies for determining the moving direction and the moving speed of the movable end 201 by the two position sensors may be used in combination or separately; when the opening degree of the proportional control valve 500 is separately controlled according to the moving speed of the movable end 201, the operator may The position of the operating mechanism 600 determines whether to activate the controller 400, and the controller 400 can also be linked with the operating mechanism 600; for example, when the operating mechanism 600 moves the movable end 201 away from the mechanical limiting mechanism 11 1 , the controller 400 is de-energized. When the operating mechanism 600 brings the movable end 201 close to the mechanical limiting mechanism 111, the controller 400 is powered.

In order to improve the adaptability of the telescopic arm, the first position sensor and the second position sensor corresponding to the mechanical limit mechanism 111 may be sequentially arranged along the telescopic direction of the telescopic cylinder 200; and the first position sensor and the second position sensor are The distance between the mechanical limiting mechanisms 111 is different; when the movable end 201 moves toward the mechanical limiting mechanism 1 11 , the first position sensor and the second position sensor can respectively generate detection signals at different times; the controller 400 The first distance between the movable end 201 and the corresponding mechanical limit mechanism can be determined according to the detection signal of the first position sensor, and the first control signal is output to the proportional control valve 500 according to a predetermined control strategy; and can be according to the second position sensor The detection signal determines a second distance between the movable end 201 and the corresponding mechanical limit mechanism, and outputs a second control signal to the proportional control valve 500 according to a predetermined control strategy; the proportional control valve 500 can be respectively according to the first control The signal and the second control signal cause the movable end 201 to move at the first speed and the second speed; Distance is greater than the second distance In the case, the first speed may be made larger than the second speed. In this way, the control system can adjust the moving speed of the movable end 201 twice, and when the movable end 201 and the corresponding mechanical limiting mechanism have different distance ranges, the movable end 201 has different moving speeds; The small proportional control valve 500 changes the opening degree when the opening degree is adjusted, and reduces the hydraulic shock generated by the change of the opening degree of the proportional control valve 500 to the hydraulic system; meanwhile, the expansion and contraction mechanism of the telescopic cylinder 200 can be reduced. At the same time as the collision impact caused by 111, the overall moving speed of the movable end 201 is maintained, the telescopic efficiency of the telescopic cylinder 200 is improved, and the safety of the telescopic arm is improved. Of course, in the opposite direction, when the movable end 201 moves away from the mechanical limiting mechanism 111, the controller 400 can output different control signals according to the detection signal of the first position sensor and the detection signal of the second position sensor to make the telescopic cylinder The 200 elongation speed is accelerated twice, and the expansion and contraction efficiency of the telescopic cylinder 200 is improved.

The controller 400 outputs a control signal to the proportional control valve 500, and changes the flow cross section thereof through the proportional control valve 500 to control the expansion and contraction speed of the telescopic cylinder 200. This can realize automatic control of the telescopic speed of the telescopic cylinder 200, which can not only improve the telescopic expansion and contraction. The accuracy of the arm control can also improve the intelligence of the control system and make the control operation of the telescopic arm more convenient.

The foregoing description of the technical solution provided by the present invention is only described by using a specific telescopic arm. It can be understood that the above technical solution is not limited to being applied to the telescopic arm of the specific structure described above, and can also be applied to other telescopic arms having a mechanical limiting mechanism; For example, in an ordinary single-cylinder multi-section telescopic arm, in order to improve the accuracy of the cylinder head positioning of the telescopic cylinder, a corresponding mechanical limit mechanism can also be set at the corresponding person position, so that the telescopic cylinder head can be better. Compared with the cylinder pin hole of the predetermined pitch arm, the operating efficiency of the telescopic arm is improved; by using the technical solution provided by the invention to control the telescopic cylinder, the hydraulic shock generated when the cylinder head is braked can be avoided; at the same time, the movable end is reduced or avoided. The effect of a collisional impact between mechanical limit mechanisms.

The present invention further provides a crane comprising a chassis and a telescopic arm, wherein the telescopic arm is rotatably connected to the chassis through a lateral hinge shaft, and the telescopic arm can be any one of the above-mentioned telescopic arms. Due to the above-mentioned telescopic arms, the crane also has a corresponding technical effect. The description of the examples is only to assist in understanding the technical solutions provided by the present invention. It should be noted that those skilled in the art can also perform without departing from the principles of the present invention. The invention is susceptible to various modifications and adaptations that fall within the scope of the appended claims.

Claims

Rights request

A telescopic arm comprising a telescopic cylinder (200), a multi-joint arm and a hydraulic system, a movable end (201) of the telescopic cylinder (200) telescopically extending in a direction in which the telescopic arm extends, the hydraulic system passing hydraulic oil The road is connected to the telescopic cylinder (200); further comprising at least one mechanical limiting mechanism cooperated with the movable end (201); characterized in that it further comprises a controller (400), a proportional control valve (500) and at least one position sensor;

The position sensor corresponds to the mechanical limit mechanism for detecting the position of the movable end (201);

The proportional control valve (500) is connected to a hydraulic oil line between the hydraulic system and the telescopic cylinder (200);

The controller (400) determines a distance between the movable end (201) and the mechanical limit mechanism according to the detection signal of the position sensor, and outputs a control signal to the proportional control valve (500) according to a predetermined control strategy; The proportional control valve (500) controls the moving speed of the movable end (201) according to the control signal;

The control strategy includes: when the distance between the active end (201) and the mechanical limit mechanism is a predetermined value, the moving speed of the movable end (201) is lowered.

2. The telescopic arm according to claim 1, comprising: a first position sensor and a second position sensor arranged in sequence along a telescopic direction of the telescopic cylinder (200), corresponding to the mechanical limit mechanism;

The controller (400) determines a first distance between the movable end (201) and the mechanical limit mechanism according to the detection signal of the first position sensor, and applies the proportional control valve (500) according to a predetermined control strategy. Outputting a first control signal; determining a second distance between the movable end (201) and the mechanical limit mechanism according to the detection signal of the second position sensor, and guiding the proportional control valve (500) according to a predetermined control strategy Outputting a second control signal; the proportional control valve (500) moving the movable end (201) at a first speed and a second speed according to the first control signal and the second control signal, respectively; the first distance is greater than the second distance The first speed is greater than the second speed.

The telescopic arm according to claim 1, wherein the controller (400) is connected to an operating mechanism (600) that controls expansion and contraction of the telescopic cylinder (200), and according to the operating mechanism

The state of (600) determines the motion state of the telescopic cylinder (200);

The control strategy includes: a distance between the active end (201) and the mechanical limit mechanism When it is a predetermined value, and the movable end (201) moves in a direction close to the mechanical stopper mechanism, the moving speed of the movable end (201) is lowered.

The telescopic arm according to claim 1, further comprising at least two position sensors sequentially arranged in a telescopic direction of the telescopic cylinder (200) and corresponding to the machine limiting mechanism;

The controller (400) determines a moving direction of the active end (201) relative to the mechanical limiting mechanism according to a sequence of detection signals generated by the position sensor;

The control strategy includes: when the distance between the active end (201) and the mechanical limit mechanism is a predetermined value, and the movable end (201) moves in a direction close to the mechanical limit mechanism, the active end ( 201) The speed of movement is reduced.

The telescopic arm according to claim 1, comprising at least two position sensors arranged in sequence along a telescopic direction of the telescopic cylinder (200), corresponding to the mechanical limit mechanism; 400) determining a moving speed of the active end (201) according to a time difference generated by the detection signal of the position sensor;

The control strategy includes: when the distance between the active end (201) and the mechanical limit mechanism is a predetermined value, and the moving speed of the movable end (201) is greater than a predetermined value, the active end (201) is predetermined a first speed movement; when the distance between the movable end (201) and the mechanical limit mechanism is a predetermined value, and the moving speed of the movable end (201) is less than a predetermined value, the movable end (201) is made to have a predetermined number Two speed motion; the first speed is greater than the second speed.

6. The telescopic arm according to claim 5, wherein

The telescopic arm according to claim 3, 4 or 6, wherein the control strategy comprises: a distance between the movable end (201) and the mechanical limit mechanism is a predetermined value, and the movable end (201) When moving in a direction away from the mechanical stopper mechanism, the moving speed of the movable end (201) is increased.

The telescopic arm according to any one of claims 1 to 6, wherein the position is transmitted The sensor is a proximity switch.

The telescopic arm according to any one of claims 1 to 6, wherein the base arm (110) of the multi-section arm and the at least one arm of the base arm (110) form a pin connection portion; At least two joint arms inside the connecting portion form a cord connecting portion; a fixed end of the telescopic cylinder (200) is fixed to an outermost joint arm of the cord connecting portion, and the movable end (201) is selectively engageable with the latch Any of the joint arms of the connecting portion is connected; each of the joint arms of the plug connecting portion is provided with the mechanical limiting mechanism.

10. A construction machine comprising a chassis and a telescopic arm, the telescopic arm being rotatably coupled to the chassis by a lateral hinge axis, wherein the telescopic arm is the telescopic arm of any of claims 1-9.