Hydraulic leveling system of traveling tower crane base

Abstract

This invention provides a hydraulic leveling system for the base of a traveling tower crane, comprising: an electric motor-hydraulic pump mechanism, consisting of an electric motor and a hydraulic pump, wherein the electric motor drives the hydraulic pump to supply oil to multiple cylinders; multiple cylinders, each connected to a leg of the traveling tower crane base to provide support force, and including rodless chambers and rod chambers; multiple electromagnetic shut-off valves, which, by opening or closing, switch the multiple cylinders between a connected state (where the rodless chambers and rod chambers are interconnected) and a disconnected state (where the rodless chambers and rod chambers are not interconnected); and multiple main control valves, connected between the electric motor-hydraulic pump mechanism and the multiple cylinders, wherein the multiple main control valves have a single-acting position and a connected position; when in the single-acting position, pressurized oil is supplied, the multiple electromagnetic shut-off valves are closed, and the cylinders are disconnected; when in the connected position, pressurized oil is cut off, the multiple electromagnetic shut-off valves are opened, and the cylinders are connected.

Description

Technical Field

[0001] This invention relates to a hydraulic leveling system for leveling the base frame of a traveling tower crane. Background Technology

[0002] Currently, tower cranes, as a type of lifting equipment, typically weigh hundreds of tons or more, with almost the entire weight transferred to the ground by the base frame. As the fundamental component of the tower crane, the levelness of the base frame is crucial during installation and operation; it must be ensured to be level at all times.

[0003] Currently, tower crane base frames are mainly divided into fixed and mobile types. The levelness of a fixed base frame is adjusted manually and via mechanical screws through embedded parts connecting to the foundation and the outrigger structure. The levelness of a mobile base frame is primarily adjusted using threaded telescopic rods located at the four outriggers.

[0004] In the method of adjusting the level of the traveling base frame, the leveling mechanism mainly relies on the threaded engagement for effective leveling. However, due to the large load on the tower crane in the vertical direction, in order to ensure the support strength of the base after leveling, the thread profile needs to be relatively coarse. Therefore, the friction is large when adjusting the thread, and the leveling process is time-consuming and laborious.

[0005] Therefore, it is necessary to design a hydraulic system that can easily level the base of the traveling tower crane and provide stable support for the four outriggers of the base. Summary of the Invention

[0006] This invention provides a hydraulic leveling system for a traveling tower crane base that uses hydraulic control to level the base and maintain stable support force, and is highly safe.

[0007] Solution for solving the problem

[0008] The technical solution of this invention is a hydraulic leveling system for the base of a traveling tower crane, characterized in that,

[0009] The hydraulic leveling system of the traveling tower crane base has the following features:

[0010] The electric motor-hydraulic pump mechanism consists of an electric motor and a hydraulic pump. The electric motor drives the hydraulic pump to supply oil to multiple cylinders.

[0011] The plurality of hydraulic cylinders are respectively connected to each of the outriggers of the traveling tower crane base frame, and are used to provide supporting force to each outrigger. The plurality of hydraulic cylinders respectively include a rodless chamber and a rod chamber.

[0012] Multiple electromagnetic shut-off valves, by opening or closing, switch the multiple hydraulic cylinders between a connected state where multiple rodless chambers are interconnected and multiple rod chambers are interconnected, and between a disconnected state where multiple rodless chambers are not interconnected and multiple rod chambers are not interconnected; and

[0013] Multiple main control valves are connected between the electric motor-hydraulic pump mechanism and the multiple hydraulic cylinders in the flow path of the pressurized oil.

[0014] The plurality of main control valves have a single-acting cylinder position and a cylinder-connected position. When the plurality of main control valves are in the single-acting cylinder position, the plurality of main control valves conduct pressure oil, the plurality of solenoid shut-off valves are closed, and the plurality of cylinders are in the cut-off state. When the plurality of main control valves are in the cylinder-connected position, the plurality of main control valves cut off pressure oil, the plurality of solenoid shut-off valves are open, and the plurality of cylinders are in the connected state.

[0015] Preferably, the hydraulic leveling system includes multiple balance valves disposed between the main control valve and the rodless chamber of the cylinder in the flow path of the pressurized oil.

[0016] Preferably, the hydraulic leveling system includes an overflow valve located between the main control valve and the electric motor-hydraulic pump mechanism in the flow path of the pressurized oil.

[0017] Preferably, the hydraulic leveling system includes multiple displacement sensors disposed in the hydraulic cylinder for detecting the displacement of the hydraulic cylinder.

[0018] Preferably, the hydraulic leveling system includes multiple pressure sensors disposed in the rodless chamber for detecting the pressure in the rodless chamber.

[0019] Preferably, the hydraulic leveling system includes multiple pressure sensors disposed in the rod chamber for detecting the pressure in the rod chamber.

[0020] Preferably, the plurality of hydraulic cylinders are connected to the outriggers in a symmetrical manner at the four corners.

[0021] Preferably, each of the outriggers corresponds to one hydraulic cylinder.

[0022] Preferably, each of the outriggers corresponds to a plurality of the hydraulic cylinders.

[0023] Preferably, the hydraulic leveling system includes a radiator for cooling the electric motor-hydraulic pump mechanism.

[0024] The effects of the invention

[0025] According to the present invention, a hydraulic leveling system for a traveling tower crane base frame is provided, which can easily level the base frame and provide stable support for the four outriggers of the base frame. Because a four-cylinder interconnection method is used to provide stable support for the base frame, the phenomenon of asynchronous stroke and pressure of multiple cylinders is avoided. This prevents vibration between the base frame and the cylinders during leveling operations, thereby preventing safety accidents such as tearing of the lug plates at the connecting cylinders, damage to the base frame, and tilting of the upper part of the tower crane. Therefore, the safety of the hydraulic leveling system for the traveling tower crane base frame is improved. Attached Figure Description

[0026] Figure 1 This is a schematic diagram illustrating the working principle of the hydraulic leveling system of the traveling tower crane base of the present invention.

[0027] Figure 2 It is a schematic diagram of the hydraulic leveling system under the individual operating conditions of each cylinder.

[0028] Figure 3 This is a schematic diagram illustrating the circuit of the hydraulic leveling system under the condition of base frame leveling. Detailed Implementation

[0029] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Furthermore, the following embodiments do not limit the technical solutions covered by the claims. Although multiple features are described in the embodiments, these multiple features do not limit the features of the technical solutions of the present invention, and multiple features can be combined arbitrarily. In the accompanying drawings, the same or similar structures are labeled with the same reference numerals, and repeated descriptions are omitted.

[0030] Unless otherwise specified, the singular forms “a,” “the,” and “the” used in this specification include the plural forms. The terms “comprising,” “including,” and “containing” used in this specification indicate the presence of the claimed feature but do not exclude the presence of one or more other features. The term “and / or” used in this specification includes any and all combinations of one or more of the relevant listed items.

[0031] When a component is described in the specification as being "on", "attached" to, "connected" to, "joined" to, or "in contact" with another component, the component may be directly located on, attached to, connected to, joined to, or in contact with the other component, or there may be an intermediate component present.

[0032] In this specification, the terms "first," "second," "third," etc., are used for ease of explanation only and are not intended to be limiting. Any technical feature represented by "first," "second," "third," etc., is interchangeable.

[0033] In the specification, spatial relation terms such as "above," "below," "front," "back," "top," and "bottom" describe the relationship between one feature and another in the accompanying drawings. It should be understood that spatial relation terms include not only the orientation shown in the drawings but also the different orientations of the device during use or operation. For example, when the device in the drawings is inverted, a feature previously described as "below" other features can now be described as "above" other features. The device can also be oriented in other ways (rotated 90 degrees or in other orientations), in which case the relative spatial relationships will be interpreted accordingly.

[0034] Figure 1 This is a schematic diagram illustrating the working principle of the hydraulic leveling system of the traveling tower crane base of the present invention. Figure 2 It is a schematic diagram of the hydraulic leveling system under the individual operating conditions of each cylinder. Figure 3 This is a schematic diagram illustrating the circuit of the hydraulic leveling system under the condition of base frame leveling.

[0035] exist Figure 1 In the attached diagram, reference numeral 1 indicates the electric motor-hydraulic pump mechanism. A relief valve 2 is connected downstream of the pressurized oil flow path of the electric motor-hydraulic pump mechanism 1. Downstream of the pressurized oil flow path of the relief valve 2, four main control valves 3-1 to 3-4, four balance valves 5-1 to 5-4, and four hydraulic cylinders 6-1 to 6-4 are sequentially connected. Additionally, this hydraulic leveling system is equipped with eight solenoid shut-off valves Y9a, Y8a, Y9b, Y8b, Y9c, Y8c, Y9d, and Y8d for controlling the flow paths.

[0036] In the following description, the four main control valves 3-1 to 3-4, the eight solenoid shut-off valves Y9a, Y8a, Y9b, Y8b, Y9c, Y8c, Y9d, Y8d, the four balance valves 5-1 to 5-4, and the four cylinders 6-1 to 6-4 are sometimes collectively referred to as main control valve 3, solenoid shut-off valve Y, balance valve 5, and cylinder 6, respectively.

[0037] In addition, Figure 1 The lower part of the image shows a radiator 7, which is used for cooling the electric motor-hydraulic pump mechanism 1. The electric motor-hydraulic pump mechanism 1 includes an electric motor 11 and a hydraulic pump 12.

[0038] The four cylinders 6-1 to 6-4 of this hydraulic leveling system are arranged symmetrically at the four corners and are connected to the four outriggers of the traveling tower crane base frame to provide support force for the four outriggers.

[0039] Each of the four hydraulic cylinders 6-1 to 6-4 has a rodless cavity 6-1a to 6-4a and a rod cavity 6-1b to 6-4b, respectively. The following explanation will take cylinder 6-1 as an example.

[0040] Of course, the number of hydraulic cylinders is not limited to four. That is, one outrigger can also correspond to two or more hydraulic cylinders, as long as it matches the number of outriggers.

[0041] During initial assembly, the mechanical connection must be made after accurately controlling the extension and retraction positions of each hydraulic cylinder to the specified positions. The following describes the process of controlling the extension and retraction of each hydraulic cylinder individually.

[0042] like Figure 2 As shown, the electric motor 11 starts, driving the hydraulic pump 12 to operate, while the radiator 7 operates simultaneously. Pressurized oil flows from the hydraulic pump 12 into the main control valve 3.

[0043] At this time, electromagnetic shut-off valves Y9a, Y8a, Y9b, Y8b, Y9c, Y8c, Y9d, and Y8d are all in the closed position.

[0044] When the potential Y4a of the main control valve 3-1 is energized, the left position of the main control valve 3-1 is open, as shown by the black arrow. Pressurized oil flows from the left position of the main control valve 3-1 into the balance valve 5-1, and then into the rodless chamber 6-1a of the cylinder 6-1. However, at this time, the solenoid shut-off valves Y8a and Y9a are not energized, and the rod chambers and rodless chambers of the four cylinders 6 are not connected. Pressurized oil flows from the rod chamber 6-1b of the cylinder 6-1 back to the oil tank (not shown) through the left position of the main control valve 3-1. At this time, the relief valve 2 acts as a safety protection to prevent excessive system pressure.

[0045] In the above state, the extension of the cylinder rod is achieved (hereinafter, sometimes simply referred to as cylinder extension).

[0046] Conversely, when the cylinder rod is to be retracted (hereinafter sometimes simply referred to as cylinder retraction), the electric motor 11 starts, driving the hydraulic pump 12 to operate, while the radiator 7 operates simultaneously. Pressurized oil flows from the hydraulic pump 12 into the main control valve 3.

[0047] At this time, electromagnetic shut-off valves Y9a, Y8a, Y9b, Y8b, Y9c, Y8c, Y9d, and Y8d are all in the closed position.

[0048] When the potential Y4b of the main control valve 3-1 is energized, the right position of the main control valve 3-1 is open, and pressurized oil flows from the right position of the main control valve 3-1 into the rod chamber 6-1b of the cylinder 6-1. However, at this time, the solenoid shut-off valves Y8a and Y9a are not energized, and the rod chambers and rodless chambers of the four cylinders 6 are not connected. The pressurized oil flows from the rodless chamber 6-1a of the cylinder 6-1 back to the oil tank (not shown) through the balance valve 5.

[0049] Therefore, by switching the energization of potentials Y4a and Y4b of the main control valve 3-1, the extension and retraction of the cylinder rod are switched.

[0050] Here, the balance valve 5 can function as a hydraulic check valve, that is, according to its set threshold, it can keep (lock) the cylinder rod of the hydraulic cylinder in a certain position.

[0051] Similarly, the connection and control methods for cylinders 6-2 to 6-4 are the same as those for cylinder 6-1.

[0052] That is, each of the four hydraulic cylinders 6-1 to 6-4 can be controlled individually so that each of the four hydraulic cylinders 6-1 to 6-4 can extend or retract independently, thereby controlling the amount of oil in each hydraulic cylinder and controlling the extension or retraction position of each hydraulic cylinder to a specified position.

[0053] When the tower crane base needs to be leveled, such as Figure 3 As shown, the main control valves 3-1 to 3-4 are all in the middle position. At this time, potentials Y9a, Y9b, Y9c, Y9d, and Y8a, Y8b, Y8c, Y8d are energized. In the diagram, the solenoid shut-off valve Y is in the right position. At this time, the rodless chambers 6-1a to 6-4a of the four cylinders 6-1 to 6-4 are connected by oil pipes, and the rod chambers 6-1b to 6-4b are connected by oil pipes. Pressurized oil flows within the oil chambers of the four cylinders, thus achieving a four-cylinder connection. When the four cylinders are connected, the four main control valves 3-1 to 3-4 operate simultaneously.

[0054] When the pressure is insufficient, the main control valve 3 replenishes oil to the oil chamber of the corresponding cylinder 6 to increase the pressure; when the pressure is too high, the main control valve 3 is in the reversing position. The balance valve 5 opens, and the pressure oil returns, reducing the pressure.

[0055] Therefore, the four hydraulic cylinders 6 can continuously and stably provide equal supporting force. When the base needs to be leveled, components such as slewing nuts and threaded screws can be used to level and calibrate the base.

[0056] As described above, since the pressure in the rodless chambers 6-1a to 6-4a is the same, the supporting force provided by the hydraulic cylinder 6 is also the same. Therefore, when the tower crane is traveling, the supporting force of the tower crane base frame can be kept stable. When the center of gravity of the upper weight shifts, the base frame can be leveled simply by using the leveling nut or threaded screw.

[0057] In addition, each of the above-mentioned hydraulic cylinders 6 is equipped with displacement sensors S01, S02, S03, and S04 for real-time monitoring of the displacement difference between the two hydraulic cylinders. Once the detection value of the above-mentioned displacement sensors S01, S02, S03, and S04 exceeds the specified value, the information of the hydraulic cylinder displacement difference exceeding the limit will be fed back to the controller, and the operator can adjust the pressure oil of the corresponding hydraulic cylinder according to the information.

[0058] In addition, four pressure sensors P04, P06, P08, and P10 are respectively installed in the rodless chambers 6-1a to 6-4a of the four cylinders, and four pressure sensors P05, P07, P09, and P11 are respectively installed in the rod chambers 6-1b to 6-4b of the four cylinders. These pressure sensors are used to monitor the pressure in the rodless chambers 6-1a to 6-4a and the rod chambers 6-1b to 6-4b in real time.

[0059] For example, when the pressure detected by the pressure sensors P04, P06, P08, and P10 in the rodless chambers 6-1a to 6-4a of the four cylinders reaches the manually set value, this information is fed back to the controller, which can then decide to perform the corresponding operation based on the oil pressure.

[0060] Alternatively, the flow rate into each hydraulic cylinder can be controlled by adjusting the opening degree of each solenoid shut-off valve.

[0061] As described above, this hydraulic leveling system uses a single electric motor to drive a hydraulic pump to supply oil to the actuators. When the tower crane moves forward and the ground becomes uneven, requiring leveling, the main control valve 3 is in the neutral position, the solenoid shut-off valve Y is in the right position, and the rodless chambers of the four cylinders 6 are interconnected, as are the rod chambers. At this time, the tower crane appears to float on the four cylinders, with each cylinder providing equal support. When the ground becomes uneven, the four cylinders extend or retract in tandem, and hydraulic oil flows within the closed system of the four cylinders.

[0062] As described above, by employing closed-loop control to level the traveling tower crane base, a hydraulic leveling system can be provided that uses hydraulic control to level the traveling tower crane base and maintain stable support force, while ensuring high safety.

[0063] According to the present invention, the traveling tower crane base can be easily leveled and a stable and equal supporting force can be provided to the four legs of the tower crane base.

[0064] Furthermore, this invention effectively prevents the vibration of the base frame and cylinders during leveling operations caused by the asynchronous stroke and pressure of multiple cylinders, thereby preventing safety accidents such as tearing of the lug plate at the connecting cylinder, damage to the base frame, and tilting of the upper part of the tower crane. Therefore, it improves the safety of the hydraulic leveling system of the traveling tower crane base frame.

[0065] As described above, this invention provides stable support force for traveling tower cranes by achieving four-cylinder interconnection, and can easily realize the individual operation of multiple cylinders and the switching between interconnection of multiple cylinders, thereby easily coping with different working conditions.

[0066] Moreover, by cleverly utilizing the connection between the rodless chambers and the rod chambers of the hydraulic cylinder, and by using an electromagnetic shut-off valve to limit the oil flow, the present invention can efficiently maintain the hydraulic cylinder pressure.

[0067] It should be noted that aspects of the invention described with respect to one embodiment can be included in other different embodiments, although these other different embodiments are not specifically described. In other words, features of all embodiments and / or any embodiments can be combined in any manner and / or combination, as long as they do not contradict each other.

Claims

1. A hydraulic leveling system for a walking tower base, the hydraulic leveling system comprising: a motor-hydraulic pump mechanism including a motor and a hydraulic pump, the motor-hydraulic pump mechanism supplying oil to a plurality of oil cylinders by driving the hydraulic pump with the motor; the plurality of oil cylinders each connected to a respective leg of the walking tower base, the plurality of oil cylinders each including a rodless chamber and a rod chamber, the plurality of oil cylinders configured to provide support to the respective legs; a plurality of electromagnetic cut-off valves configured to switch between a communication state in which the plurality of oil cylinders are in communication with each other through the plurality of rodless chambers and the plurality of rod chambers, and a cut-off state in which the plurality of oil cylinders are not in communication with each other; and a plurality of master valves disposed between the motor-hydraulic pump mechanism and the plurality of oil cylinders in a flow path of the pressure oil, the plurality of master valves having a cylinder single-acting position and a cylinder communication position, the plurality of master valves being configured to pass the pressure oil when the plurality of master valves are in the cylinder single-acting position, the plurality of electromagnetic cut-off valves being closed, and the plurality of oil cylinders being in the cut-off state, the plurality of master valves being configured to block the pressure oil when the plurality of master valves are in the cylinder communication position, the plurality of electromagnetic cut-off valves being opened, and the plurality of oil cylinders being in the communication state.

2. The hydraulic leveling system for a walking tower base according to claim 1, the hydraulic leveling system further comprising: a plurality of balance valves disposed between the master valves and the rodless chambers of the oil cylinders in the flow path of the pressure oil.

3. The hydraulic leveling system for a walking tower base according to claim 1 or 2, the hydraulic leveling system further comprising: a plurality of relief valves disposed between the master valves and the motor-hydraulic pump mechanism in the flow path of the pressure oil.

4. The hydraulic leveling system for a walking tower base according to claim 1 or 2, the hydraulic leveling system further comprising: a plurality of displacement sensors disposed in the oil cylinders and configured to detect displacement of the oil cylinders.

5. The hydraulic leveling system for a walking tower base according to claim 1 or 2, the hydraulic leveling system further comprising: a plurality of pressure sensors disposed in the rodless chambers and configured to detect pressure of the rodless chambers.

6. The hydraulic leveling system for a walking tower base according to claim 5, the hydraulic leveling system further comprising: a plurality of pressure sensors disposed in the rod chambers and configured to detect pressure of the rod chambers.

7. The hydraulic leveling system for a walking tower base according to claim 1 or 2, wherein the plurality of oil cylinders are each connected to the legs in a four-corner symmetrical manner.

8. The hydraulic leveling system for a walking tower base according to claim 1 or 2, wherein each of the legs corresponds to one of the oil cylinders.

9. The hydraulic leveling system for a walking tower base according to claim 1 or 2, wherein each of the legs corresponds to a plurality of the oil cylinders.

10. The hydraulic leveling system for a walking tower base according to claim 1 or 2, wherein ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The hydraulic leveling system is provided with a radiator for radiating the motor-hydraulic pump mechanism. The hydraulic leveling system is provided with a radiator for radiating the motor-hydraulic pump mechanism.

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