Concrete pumping equipment and its hydraulic system

Abstract

The present application discloses a concrete pumping device and its hydraulic system. The concrete pumping device hydraulic system includes a pumping cylinder group, including a chamber A as a rodless chamber, a chamber B as a rod chamber, and a chamber C as a piston rod chamber; a cylinder control hydraulic system for selecting a chamber as a working chamber and starting and stopping the concrete pumping device; a hydraulic chamber auxiliary control hydraulic system, including a plurality of chamber connection oil circuits respectively connected to the chambers of the pumping cylinder group and respectively provided with oil circuit control valves, and used to control the oil volume in the chambers serving as connecting chambers in the pumping cylinder group in a pumping working state to be stable. According to the concrete pumping device and its hydraulic system of the present application, by adding a hydraulic chamber auxiliary control hydraulic system and combining the chamber oil volume control strategy, the main connecting chamber in the pumping cylinder group can be replenished or drained in time in the pumping working state to prevent the occurrence of cylinder blockage, cylinder collision, excessive pressure, etc.

Description

Technical Field

[0001] The present application belongs to the technical field of concrete pumping, and in particular, relates to a concrete pumping device and a hydraulic system thereof. Background Art

[0002] Figure 1 、 Figure 2 The figure shows a common concrete pumping equipment with two pumping states, namely high pressure state and low pressure state. This pumping equipment generally uses a double-acting single piston rod in series with a cylinder, one cylinder extends forward and the other retracts, driving the concrete cylinder piston to suck or push the material to achieve concrete delivery. However, in actual construction, the concrete material condition varies greatly, and the concrete delivery pressure and speed vary greatly in different construction scenarios. For this reason, a high-low pressure conversion device is generally used, such as Figure 1 As shown in the figure, when the pressure oil is passed into the rodless chamber of a cylinder, the system is in a high-pressure state, the concrete pumping pressure is high, but the output volume is small. Figure 2 As shown, when pressurized oil is introduced into the rod chamber of one cylinder, the system is in a low-pressure pumping state. The concrete pumping pressure is low, but the output volume is large. This can adapt to a wider range of construction conditions. However, this solution can only provide two pumping states and cannot adapt to a wider range of concrete delivery pressures and speeds.

[0003] Chinese patent application CN201410584350.7 proposes a new three-chamber oil cylinder solution, which divides an oil cylinder into three oil chambers, namely the rod chamber, the rodless chamber, and the piston rod chamber. Due to the different effective areas of each chamber, when different oil chambers are used as working chambers, the maximum thrust and maximum speed of the oil cylinder are different, thus theoretically forming six pressure states. Under different working conditions, different pressure states can be used for pumping, thereby greatly improving the ability of the pumping equipment to adapt to working conditions. However, at the same time, although this multi-stage pumping solution has a stronger ability to adapt to working conditions, it also has some shortcomings. In particular, when there is an oil leak, it is difficult to ensure the reverse synchronization of the piston rods of the two cylinders, which may lead to operational failures of the pumping cylinder group. Summary of the Invention

[0004] The purpose of the present application is to provide a concrete pumping equipment and its hydraulic system to effectively avoid cylinder blocking, cylinder collision, pressure shock and the like, and ensure that the piston rod of the pumping cylinder maintains reverse synchronization.

[0005] According to a first aspect of the present application, a hydraulic system for concrete pumping equipment is provided, comprising:

[0006] The pumping cylinder group includes a chamber A as a rodless chamber, a chamber B as a rod chamber, and a chamber C as a piston rod chamber;

[0007] Cylinder control hydraulic system, used to select the chamber as the working chamber and start and stop control of concrete pumping equipment;

[0008] The hydraulic chamber auxiliary control hydraulic system includes multiple chamber connecting oil circuits respectively connected to the various chambers of the pumping cylinder group and respectively provided with oil circuit control valves, and is used to control the stability of the oil amount in the chamber serving as the connecting chamber in the pumping cylinder group in the pumping working state.

[0009] In some embodiments, each chamber in the pumping cylinder group is provided with an oil level detection element for detecting whether the oil level in the chamber is too high or too low. The hydraulic chamber auxiliary control hydraulic system includes a controller configured to:

[0010] Determining that the controlled concrete pumping equipment is started and is in a pumping working state;

[0011] Regarding the A chamber, B chamber and C chamber, the working chamber for connecting the working pressure oil and the main communication chamber for pushing the piston in reverse synchronization are respectively determined;

[0012] The oil level detection signal of the oil level detection element in the main communicating chamber is obtained, and the oil circuit control valve in the chamber connecting oil circuit corresponding to the main communicating chamber is controlled accordingly, so that the main communicating chamber performs corresponding oil replenishment or oil draining through the corresponding chamber connecting oil circuit.

[0013] In some embodiments, the controller is further configured to:

[0014] Control to disconnect the chamber connecting oil circuit corresponding to the working chamber.

[0015] In some embodiments, the controller is further configured to:

[0016] Determine the passively connected cavity without load drive among the cavity A, cavity B, and cavity C;

[0017] The chamber corresponding to the passive communication chamber is controlled to connect to the oil circuit to return oil or to connect to a low-pressure oil source.

[0018] In some embodiments, in the chamber connecting oil circuit corresponding to the passive communicating chamber, the oil inlet of the oil circuit control valve is connected to the oil pumping circuit of the oil replenishment pump.

[0019] In some embodiments, the controller is further configured to:

[0020] Determining that the controlled concrete pumping equipment stops working;

[0021] The plurality of oil circuit control valves are controlled so that all the chamber connection oil circuits are disconnected.

[0022] In some embodiments, the hydraulic chamber assists in controlling the hydraulic system, including:

[0023] Chamber A is connected to an oil circuit, connected to said chamber A and provided with a first oil circuit control valve;

[0024] The B chamber is connected to the oil circuit, which is connected to the B chamber and is provided with a second oil circuit control valve;

[0025] The C chamber is connected to the oil circuit, which is connected to the C chamber and is provided with a third oil circuit control valve;

[0026] The first oil circuit control valve, the second oil circuit control valve and the third oil circuit control valve are all electromagnetic reversing valves and communicate with the controller respectively.

[0027] In some embodiments, the pumping cylinder group includes a first pumping cylinder and a second pumping cylinder in parallel, and the A chamber connecting oil circuit, the B chamber connecting oil circuit, and the C chamber connecting oil circuit are respectively and individually connected to the A chamber, B chamber, and C chamber of any one of the first pumping cylinder and the second pumping cylinder, or the A chamber connecting oil circuit, the B chamber connecting oil circuit, and the C chamber connecting oil circuit are respectively and simultaneously connected to the A chamber, B chamber, and C chamber of the first pumping cylinder and the second pumping cylinder.

[0028] In some embodiments, the first oil circuit control valve, the second oil circuit control valve, and the third oil circuit control valve are all three-position four-way reversing valves.

[0029] In some embodiments, the cylinder control hydraulic system is configured to maintain the B chamber as the main connecting chamber in the pumping working state, the first oil circuit control valve and the third oil circuit control valve are both two-position two-way reversing valves, and the second oil circuit control valve is a three-position four-way reversing valve.

[0030] In some embodiments, the first oil circuit control valve and the third oil circuit control valve are integrated into a three-position four-way reversing valve.

[0031] In some embodiments, a damping element is provided in the chamber connecting oil circuit.

[0032] According to a second aspect of the present application, a concrete pumping equipment is provided, wherein the concrete pumping equipment includes the above-mentioned concrete pumping equipment hydraulic system.

[0033] In the concrete pumping equipment and hydraulic system thereof according to the present application, a hydraulic chamber auxiliary control hydraulic system is added to provide a chamber oil quantity control strategy, so that in the pumping working state, the main connecting chamber or the passive connecting chamber in the pumping cylinder group can replenish or drain oil in time; specifically, three electromagnetic reversing valves can be used to respectively control the oil replenishment and oil drain of each connecting chamber of the cylinder, which can effectively adjust the oil quantity of the connecting chamber. In various working states, it can effectively prevent the abnormal changes or incoordination of the oil quantity in the connecting chamber from causing the two cylinder strokes to fail to meet the requirements, the cylinders to be blocked, the cylinders to collide, the pressure is too high, etc., so that the pumping equipment can work normally.

[0034] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following detailed embodiments, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. In the accompanying drawings:

[0036] Figure 1 、 Figure 2 The diagrams respectively show common concrete pumping equipment with two pumping states in its high-pressure state and low-pressure state;

[0037] Figure 3 It is a hydraulic principle diagram of a concrete pumping equipment with a three-chamber oil cylinder;

[0038] Figure 4 、 Figure 5 All showed Figure 3 The concrete pumping setup shown shows a situation where the piston rods of the two cylinders cannot maintain reverse synchronization;

[0039] Figure 6 A hydraulic principle diagram of a concrete pumping device and a hydraulic system thereof according to a first embodiment of the present application;

[0040] Figure 7 for Figure 6 A control flow chart of the concrete pumping equipment shown;

[0041] Figure 8 A hydraulic principle diagram of a concrete pumping device and a hydraulic system thereof according to a second embodiment of the present application;

[0042] Figure 9 1 is a hydraulic principle diagram of a concrete pumping device and a hydraulic system thereof according to a third embodiment of the present application;

[0043] Figure 10 for Figure 9 A control flow chart of the concrete pumping equipment shown;

[0044] Figure 11 1 is a hydraulic principle diagram of a concrete pumping device and a hydraulic system thereof according to a fourth embodiment of the present application;

[0045] Figure 12 A hydraulic principle diagram of a concrete pumping device and a hydraulic system thereof according to a fifth embodiment of the present application; and

[0046] Figure 13 4 is a hydraulic principle diagram of a concrete pumping device and a hydraulic system thereof according to a sixth embodiment of the present application. DETAILED DESCRIPTION

[0047] The following describes the specific embodiments of the present application in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present application and are not intended to limit the present application.

[0048] The concrete pumping equipment and the hydraulic system thereof according to the present application will be described below with reference to the accompanying drawings.

[0049] exist Figure 4 In the concrete pumping setup shown, when cavity C is the working oil cavity, cavity A and cavity B are connecting cavities, cavity A1 is connected to cavity A2, and cavity B1 is connected to cavity B2. Theoretically, without considering leakage, the amount of oil in the connecting cavity will not change, and the piston rods of the two cylinders will remain in reverse synchronization, that is, when the piston rod of one cylinder is extended to the position, the piston rod of the other cylinder just retracts to the position. However, in actual work, leakage is inevitable, and the leakage can come from the cylinder, the hydraulic components connected to the various cavities of the cylinder, and so on. Leakage will cause the oil in the connecting cavity to decrease or increase, thereby affecting the reverse synchronization accuracy of the piston rods of the two cylinders. Figure 5 As shown, when the oil volume in the connecting chambers B1 and B2 decreases, the piston rod of one cylinder will be fully extended while the piston rod of the other cylinder will remain in the middle position and not retracted. This situation can cause cylinder blockage, cylinder collision, and pressure shock, reducing system efficiency and seriously affecting normal equipment operation. If the oil volume in the connecting chamber B is normal but the oil volume in chamber A is excessive, the pressure in chambers A and B may increase, and chamber B may even be over-pressurized due to the pressurization effect.

[0050] It can be seen that in the multi-stage pumping scheme of the three-chamber oil cylinder, if the two connecting chambers do not match, or the oil volume in the two connecting chambers is too much or too little, it will affect the normal operation of the system. In order to effectively solve the problem of abnormal oil volume changes in the connecting cylinders of the pumping cylinder and the problem caused by the asynchronous oil volume changes, this application proposes a new hydraulic control scheme for the pumping cylinder, that is, discloses a hydraulic system for concrete pumping equipment. Figure 6 As shown, in a specific embodiment, the hydraulic system of the concrete pumping equipment includes:

[0051] The pumping cylinder group includes a chamber A as a rodless chamber, a chamber B as a rod chamber, and a chamber C as a piston rod chamber;

[0052] Cylinder control hydraulic system, used to select the chamber as the working chamber and start and stop control of concrete pumping equipment;

[0053] The hydraulic chamber auxiliary control hydraulic system includes multiple chamber connecting oil circuits respectively connected to the various chambers of the pumping cylinder group and respectively provided with oil circuit control valves, and is used to control the stability of the oil amount in the chamber serving as the connecting chamber in the pumping cylinder group in the pumping working state.

[0054] The pumping cylinder group in this hydraulic system has three-chamber cylinders, which are used to achieve multi-stage pumping. The cylinder control hydraulic system is used to select the chamber as the working chamber and start and stop the concrete pumping equipment. Figure 3 The illustrated hydraulic oil circuit system with multiple cartridge valves enables the selection of working chambers and the introduction of pressurized oil by controlling the communication of each cartridge valve, while also interconnecting the communicating chambers, thereby driving the cylinder group via a hydraulic pump to pump concrete. However, it should be noted that the cylinder control hydraulic system is not critical to this application and is well known to those skilled in the art, so it will not be described in detail here.

[0055] The core of this application is to add a hydraulic chamber to assist in controlling the hydraulic system, including Figure 6 As shown in the figure, multiple chamber connecting oil circuits with electromagnetic reversing valves (i.e., oil circuit control valves) are controlled to ensure that the amount of oil in the chamber serving as the connecting chamber is always kept stable during the operation of the pumping equipment.

[0056] To achieve a stable oil level in the connecting chamber, the present application provides a chamber oil level control strategy. First, during the pumping operation, the main connecting chamber in the pumping cylinder group can be replenished or drained in a timely manner. Therefore, each chamber in the pumping cylinder group is equipped with an oil level detection element (not shown) for detecting excessive or insufficient oil in the chamber. The hydraulic chamber auxiliary control hydraulic system may include a controller configured to:

[0057] Ensure that the concrete pumping equipment is started and in pumping working state;

[0058] Regarding chamber A, chamber B, and chamber C, the working chamber for connecting the working pressure oil and the main communicating chamber for pushing the piston in reverse synchronization are determined respectively;

[0059] The oil level detection signal of the oil level detection element in the main communicating chamber is obtained, and the oil circuit control valve in the chamber connecting oil circuit corresponding to the main communicating chamber is controlled accordingly, so that the main communicating chamber can perform corresponding oil replenishment or oil drainage through the corresponding chamber connecting oil circuit.

[0060] It should be noted that in a three-chamber oil cylinder, when one is determined to be the working chamber, the other two are the main connecting chamber and the passive connecting chamber. The corresponding main connecting chambers and passive connecting chambers in the two oil cylinders are connected to each other. The main connecting chamber refers to the connecting chamber that needs to push the piston rod to move and requires a certain pressure to push the load. The remaining passive connecting chambers are connecting chambers that do not need to push the load.

[0061] Under this chamber oil quantity control strategy, actively and positively maintaining the stability of the oil quantity in the main connecting chamber in real time can ensure to the greatest extent that the telescopic stroke position of the piston rod pushing the load is accurate and the piston rods of the two cylinders remain in reverse synchronization.

[0062] Furthermore, the passive communication chamber is controlled to maintain an oil return state or be connected to a low-pressure oil source to eliminate or reduce the influence of the passive communication chamber on the piston stroke. That is, the controller can also be configured as follows:

[0063] Determine the passively connected cavity without load drive among the cavity A, cavity B, and cavity C;

[0064] The chamber corresponding to the passive communication chamber is controlled to connect to the oil circuit to return oil or to connect to a low-pressure oil source.

[0065] The passive communication chamber can be switched back to oil via an oil circuit control valve, or it can be connected to the system's low-pressure oil circuit. For example, the oil inlet of the oil circuit control valve in the chamber connecting the passive communication chamber can be connected to the system's charge pump's oil supply circuit. Those skilled in the art are well aware that compared to the main pump, the charge pump has a relatively low pumping pressure and flow rate.

[0066] In addition, under this chamber oil quantity control strategy, the controller can also be configured as follows:

[0067] Control and disconnect the chamber connecting oil circuit corresponding to the working chamber.

[0068] That is, the two corresponding chambers serving as working chambers need to be disconnected so that when pressurized oil is introduced into the working chamber of one oil cylinder, oil can be returned to the working chamber of the other oil cylinder, thereby normally driving the telescopic action of the double piston rods.

[0069] The above are all switching control strategies for the oil circuits connecting each chamber in the hydraulic chamber auxiliary control hydraulic system and their oil circuit control valves (i.e., the first oil circuit control valve 4, the second oil circuit control valve 5, and the third oil circuit control valve 3 shown in the figure, all of which are electromagnetic reversing valves) during normal operation of the pumping equipment. Correspondingly, corresponding control should also be implemented when the pumping equipment stops working. Therefore, the controller can also be configured as follows:

[0070] Determine and control the concrete pumping equipment to stop working;

[0071] Control multiple oil circuit control valves so that all chamber connection oil circuits are disconnected.

[0072] It can be seen that when the concrete pumping equipment is not working, it is sufficient to disconnect the oil circuits connecting the various chambers in the hydraulic chamber auxiliary control hydraulic system.

[0073] See also Figures 6 to 13 , the hydraulic chamber auxiliary control hydraulic system in each embodiment includes:

[0074] Chamber A is connected to the oil circuit, which is connected to chamber A and is provided with a first oil circuit control valve 4;

[0075] Chamber B is connected to the oil circuit, which is connected to chamber B and is provided with a second oil circuit control valve 5;

[0076] The C chamber is connected to the oil circuit, which is connected to the C chamber and is provided with a third oil circuit control valve 3;

[0077] The first, second, and third oil control valves 4, 5, and 3 are all electromagnetic reversing valves that communicate with the controller. This hydraulic circuit design, combined with the aforementioned chamber oil quantity control strategy, resolves numerous issues related to abnormal and asynchronous oil quantity changes within the interconnected chambers.

[0078] by Figure 6 For example, the pumping cylinder group may include a first pumping cylinder 1 and a second pumping cylinder 2 in parallel, and the A chamber connecting oil path, the B chamber connecting oil path and the C chamber connecting oil path are respectively connected to the A chamber, the B chamber and the C chamber of any one of the first pumping cylinder 1 and the second pumping cylinder 2. Figures 6 to 13 In various embodiments, as an example, the chamber A connecting oil circuit, the chamber B connecting oil circuit, and the chamber C connecting oil circuit are individually connected to chamber A, chamber B, and chamber C of the first pumping cylinder 1, respectively. Obviously, the chamber A connecting oil circuit, the chamber B connecting oil circuit, and the chamber C connecting oil circuit can also be simultaneously connected to chamber A, chamber B, and chamber C of the first pumping cylinder 1 and the second pumping cylinder 2, respectively. Furthermore, for the sake of clarity, the cylinder control hydraulic system used to select the chamber to be used as the working chamber and to start and stop the concrete pumping equipment is omitted from illustration.

[0079] exist Figure 6 As an example, the first oil circuit control valve 4, the second oil circuit control valve 5 and the third oil circuit control valve 3 all adopt common three-position four-way reversing valves, and each reversing valve has an intermediate cut-off position and a left and right reversing position controlled by an electromagnet.

[0080] exist Figure 8 In the embodiment, a damping element 6 may be provided in the chamber connecting oil circuit to control the flow rate of oil replenishment or oil leakage in the control connecting chamber.

[0081] When chamber B is always used as the main communicating chamber, that is, the oil cylinder control hydraulic system is set to keep chamber B as the main communicating chamber in the pumping working state, the first oil circuit control valve 4 and the third oil circuit control valve 3 can both adopt a simpler two-position two-way reversing valve, and the second oil circuit control valve 5 is a three-position four-way reversing valve. Figure 9 shown.

[0082] Similarly, in Figure 11 In the embodiment, a damping element may be provided in the chamber connecting oil circuit to control the flow in the chamber connecting oil circuit.

[0083] exist Figure 12 In the embodiment, the chamber connecting oil path corresponding to the passive communicating cavity is connected to the low-pressure oil source, as long as the main communicating cavity does not generate negative pressure.

[0084] It is understood by those skilled in the art that Figure 11 、 Figure 12 In the embodiment shown, the first oil circuit control valve 4 and the third oil circuit control valve 3 can also be integrated into a three-position four-way reversing valve, such as Figure 13 shown.

[0085] The present application also discloses a concrete pumping device, including the above-mentioned concrete pumping device hydraulic system. Obviously, the concrete pumping device of the present application can have a multi-stage pumping function, a precise pumping process, good synchronization of the pumping cylinder group, and is not prone to failure.

[0086] The hydraulic system structure and control process of each specific embodiment are described in detail below with reference to the accompanying drawings.

[0087] First embodiment:

[0088] like Figure 6 As shown, the hydraulic system includes a first pumping cylinder 1 and a second pumping cylinder 2, both three-chamber cylinders. It also includes a third oil circuit control valve 3, a first oil circuit control valve 4, and a second oil circuit control valve 5. Each of the three oil circuit control valves (hereinafter referred to as solenoid reversing valves) has a working oil port connected to the C1, A1, and B1 chambers of the first pumping cylinder 1, respectively. The P port of the solenoid reversing valve is connected to a pressure oil source, while the T port of the solenoid reversing valve returns to the oil tank. The solenoid reversing valve has three positions. The left position connects the C1, A1, and B1 chambers of the three-chamber cylinder to the oil tank. These chambers can drain oil through the solenoid reversing valve. If negative pressure develops in these chambers, oil can be replenished from the oil tank. The right position connects the C1, A1, and B1 chambers of the three-chamber cylinder to the pressure oil source, which then replenishes oil to each chamber through the solenoid reversing valve. The neutral position disconnects the C1, A1 and B1 chambers of the three-chamber oil cylinder from the pressure oil source and the oil tank.

[0089] It should be noted that the working oil port of the electromagnetic reversing valve can also be connected to the corresponding cavity of the second pumping cylinder 2. During the process of returning to the oil tank through the T port, it can also pass through other components, such as a filter and a cooler, and then return to the oil tank. This should not limit the scope of protection of this application.

[0090] Theoretically, the T port of the electromagnetic reversing valve can also be connected to a low-pressure oil source, so that when the A communicating chamber or the C communicating chamber is a passive communicating chamber, it can effectively prevent the passive communicating chamber from generating negative pressure.

[0091] The corresponding control logic diagram is shown in Figure 7 , the control strategy is described as follows:

[0092] The hydraulic system uses chamber A as the working chamber. The system's operating oil flows in and out of chambers A1 and A2, pushing the piston rod back and forth. Here, chambers C1 and C2 are connected to form chamber C, while chambers B1 and B2 are connected to form chamber B. A1 and A2 are disconnected. Chamber C does not require load and is a passive chamber. Chamber B, on the other hand, requires a certain pressure to retract the piston rod and is the primary chamber.

[0093] The control strategy is as follows:

[0094] During pumping, the left magnet of the third oil circuit control valve 3 is energized, the C communicating chamber is connected to the T port, and the oil in the C communicating chamber can be discharged to the oil tank, or when the oil in the C communicating chamber is too little, the oil can be replenished from the oil tank.

[0095] During pumping, the electromagnets of the first oil circuit control valve 4 are all de-energized, and the A1 cavity is disconnected from the pressure oil source and the oil tank.

[0096] During pumping, the energizing state of the second oil circuit control valve 5 is determined by the oil level in connecting chamber B. When the controller detects that connecting chamber B is low on oil and needs to be replenished, the right solenoid is energized, and the pressure oil source replenishes oil to connecting chamber B through the solenoid reversing valve. When the controller detects that connecting chamber B is high on oil and needs to be drained, the left solenoid is energized, and the connecting chamber drains oil to the tank through the solenoid reversing valve. If the controller detects that neither replenishment nor draining is necessary, both solenoids in the solenoid reversing valve are de-energized, disconnecting connecting chamber B from the pressure oil source and the tank.

[0097] When pumping stops, all electromagnets are de-energized.

[0098] It should be noted that, in theory, the right electromagnet of the third oil circuit control valve 3 can also be energized, and the C connecting chamber can communicate with the pressure oil source to maintain a certain pressure of the oil in the connecting chamber, and the oil volume in the C connecting chamber can also be kept to meet the requirements.

[0099] When chamber C is the working chamber, the system's operating oil flows in and out of the three-chamber cylinder through chambers C1 and C2, pushing the piston rod back and forth. Here, chambers A1 and A2 are connected to form chamber A, while chambers B1 and B2 are connected to form chamber B. C1 and C2 are disconnected. Chamber A does not require any load and is a passive chamber. Chamber B, on the other hand, requires a certain pressure to retract the piston rod and is the primary chamber.

[0100] Correspondingly, the control strategy is as follows:

[0101] During pumping, the electromagnets of the third oil circuit control valve 3 are all de-energized, and the C1 chamber is disconnected from the pressure oil source and the oil tank.

[0102] During pumping, the left electromagnet of the first oil circuit control valve 4 is energized, the A communicating chamber is communicated with the T port, and the oil in the A communicating chamber can be discharged to the oil tank, or when the oil in the A communicating chamber is too little, the oil can be replenished from the oil tank.

[0103] During pumping, the energizing state of the second oil circuit control valve 5 is determined by the oil level in connecting chamber B. When the controller detects that connecting chamber B is low on oil and needs to be replenished, the right solenoid is energized, and the pressure oil source replenishes oil to connecting chamber B through the solenoid reversing valve. When the controller detects that connecting chamber B is high on oil and needs to be drained, the left solenoid is energized, and the connecting chamber drains oil to the tank through the solenoid reversing valve. If the controller detects that neither replenishment nor draining is necessary, both solenoids in the solenoid reversing valve are de-energized, disconnecting connecting chamber B from the pressure oil source and the tank.

[0104] When pumping stops, all electromagnets are de-energized.

[0105] It should be noted that, in theory, the right electromagnet of the first oil circuit control valve 4 can also be energized, and the A connecting chamber is connected to the pressure oil source, so that the oil in the connecting chamber maintains a certain pressure, and the oil volume in the C connecting chamber can also be kept to meet the requirements.

[0106] When the system uses chamber B as the working chamber, the system working oil flows in and out of the three-chamber oil cylinder from B1 and B2, pushing the piston rod to reciprocate. At this time, A1 and A2 are connected to form chamber A, C1 and C2 are connected to form chamber C, and B1 and B2 are not connected. In this case, there are three situations for chambers A and C: (1) Chamber A is the main chamber, and chamber C is the passive chamber; (2) Chamber A is the passive chamber, and chamber C is the main chamber; (3) Both chambers A and C are main chambers. In actual work, you can choose one, or you can use different methods according to different working conditions.

[0107] The corresponding control strategy is as follows:

[0108] For the passive connecting chamber, the corresponding left electromagnet of the electromagnetic reversing valve is energized, so that the connecting chamber is connected with the oil tank.

[0109] The main connecting chamber is replenished or drained based on the system's assessment of the oil level. When the controller detects that the connecting chamber is low on oil and needs replenishment, the right solenoid is energized, causing the pressure oil source to replenish oil to the main connecting chamber via the solenoid reversing valve. When the controller detects that the main connecting chamber is overfilled and needs draining, the left solenoid is energized, causing the main connecting chamber to drain oil to the tank via the solenoid reversing valve. When the controller detects that neither replenishment nor draining is necessary, the solenoids in the solenoid reversing valve are de-energized, disconnecting the connecting chamber, the pressure oil source, and the tank.

[0110] When pumping stops, all electromagnets are de-energized.

[0111] It should be noted that, in theory, the electromagnetic reversing valve connected to the passive connecting chamber can also be energized by the right electromagnet, so that the connecting chamber is connected to the pressure oil source, so that the oil in the connecting chamber maintains a certain pressure, and the oil volume in the connecting chamber can also be kept to meet the requirements.

[0112] When A+C chambers are used as the working chambers, the system working oil flows in and out of the three-chamber cylinder from A1, A2, C1, and C2, pushing the piston rod to reciprocate. At this time, B1 and B2 are connected to form the B connecting chamber.

[0113] The control strategy is as follows:

[0114] Since A1, A2, C1 and C2 are all connected to the working oil, in the pumping state, the corresponding electromagnets of the third oil circuit control valve 3 and the first oil circuit control valve 4 are de-energized, so that A1 and C1 are disconnected from the pressure oil source and the oil tank.

[0115] During pumping, the energizing state of the second oil circuit control valve 5 is determined by the oil level in connecting chamber B. When the controller detects that connecting chamber B is low on oil and needs to be replenished, the right solenoid is energized, and the pressure oil source replenishes oil to connecting chamber B through the solenoid reversing valve. When the controller detects that connecting chamber B is high on oil and needs to be drained, the left solenoid is energized, and the connecting chamber drains oil to the tank through the solenoid reversing valve. If the controller detects that neither replenishment nor draining is necessary, both solenoids in the solenoid reversing valve are de-energized, disconnecting connecting chamber B from the pressure oil source and the tank.

[0116] When pumping stops, all electromagnets are de-energized.

[0117] Second embodiment:

[0118] like Figure 8 As shown, in order to control the flow of oil replenishment or oil leakage in the connecting chamber, damping can be added to the pressure oil source oil circuit and the working oil circuit of each electromagnetic reversing valve. Of course, damping can also be added to one or several oil circuits.

[0119] Third embodiment:

[0120] When B1 and B2 always serve as connecting cavities, such as Figure 9As shown, the hydraulic system includes a first pumping cylinder 1, a second pumping cylinder 2, a two-position third oil circuit control valve 3, a two-position first oil circuit control valve 4, and a second oil circuit control valve 5. The use of two two-position solenoid directional valves simplifies the system and reduces costs. Of course, the two-position, two-way solenoid directional valve can also be a two-position, three-way solenoid directional valve.

[0121] Among them, port 1 of the third oil circuit control valve 3 is connected to chamber C1, and port 2 is connected to the oil tank. Port 1 of the first oil circuit control valve 4 is connected to chamber A1, and port 2 is connected to the oil tank. One working oil port of the second oil circuit control valve 5 is connected to chamber B1, pressure oil port P is connected to the pressure oil source, and return port T is connected to the oil tank.

[0122] It should be noted that the working oil ports of the third oil circuit control valve 3, the first oil circuit control valve 4, and the second oil circuit control valve 5 can also be connected to the corresponding chambers of the second pumping cylinder 2. During the process of returning to the oil tank from the T port, they can also first pass through other components, such as filters and coolers, and then return to the oil tank. This should not limit the scope of protection of this application.

[0123] The third oil circuit control valve 3 and the first oil circuit control valve 4 are both two-position two-way electromagnetic reversing valves in the figure, and two-position three-way valves, two-position four-way valves, etc. can also be used, but the present application is not limited thereto.

[0124] The corresponding control logic flow chart is shown in Figure 10 , the control strategy is described as follows:

[0125] With chamber A as the working chamber, the system's operating oil flows through chambers A1 and A2, pushing the piston rod back and forth. C1 and C2 connect to form chamber C, while B1 and B2 connect to form chamber B. A1 and A2 are disconnected. Chamber C does not require load and is a passive chamber. Chamber B, which requires a certain pressure to retract the piston rod, is the primary chamber.

[0126] The control strategy is as follows:

[0127] During pumping, the electromagnet of the third oil circuit control valve 3 is energized, the C communicating chamber communicates with the oil tank, and the oil in the C communicating chamber can be discharged to the oil tank, or when the oil in the C communicating chamber is too little, the oil can be replenished from the oil tank.

[0128] During pumping, the electromagnet of the first oil circuit control valve 4 loses power, and the A1 chamber is disconnected from the oil tank.

[0129] During pumping, the energizing state of the second oil circuit control valve 5 is determined by the oil level in connecting chamber B. When the controller detects that connecting chamber B is low on oil and needs to be replenished, the right solenoid is energized, and the pressure oil source replenishes oil to connecting chamber B through the solenoid reversing valve. When the controller detects that connecting chamber B is high on oil and needs to be drained, the left solenoid is energized, and the connecting chamber drains oil to the tank through the solenoid reversing valve. If the controller detects that neither replenishment nor draining is necessary, both solenoids in the solenoid reversing valve are de-energized, disconnecting connecting chamber B from the pressure oil source and the tank.

[0130] When pumping stops, all electromagnets are de-energized.

[0131] With chamber C as the working chamber, the system's operating oil flows in and out of the three-chamber cylinder through chambers C1 and C2, pushing the piston rod back and forth. A1 and A2 connect to form chamber A, while B1 and B2 connect to form chamber B. C1 and C2 are disconnected. Chamber A does not require any load and is a passive chamber. Chamber B, which requires a certain pressure to retract the piston rod, is the primary chamber.

[0132] The control strategy is as follows:

[0133] During pumping, the electromagnet of the first oil circuit control valve 4 is energized, the A communicating chamber communicates with the oil tank, and the oil in the A communicating chamber can be discharged to the oil tank, or when the oil in the A communicating chamber is too little, the oil can be replenished from the oil tank.

[0134] During pumping, the electromagnet of the third oil circuit control valve 3 loses power, and the C1 chamber is disconnected from the oil tank.

[0135] During pumping, the power on and off of the second oil circuit control valve 5 is determined by the oil level in connecting chamber B. When the controller detects that connecting chamber B is low on oil and needs to be replenished, the right solenoid is energized, and the pressure oil source replenishes oil to connecting chamber B through the solenoid reversing valve. When the controller detects that connecting chamber B is high on oil and needs to be drained, the left solenoid is energized, and the connecting chamber drains oil to the tank through the solenoid reversing valve. If the controller detects that oil replenishment or draining is not necessary, both solenoids in the solenoid reversing valve are de-energized, disconnecting connecting chamber B from the pressure oil source and the tank.

[0136] When pumping stops, all electromagnets are de-energized.

[0137] When A+C chambers are used as the working chambers, the system's working oil flows in and out of the three-chamber cylinder from A1, A2, C1, and C2, pushing the piston rod to reciprocate. At this time, B1 and B2 are connected to form the B connecting chamber.

[0138] The control strategy is described as follows:

[0139] Since A1, A2, C1 and C2 are all connected to the working oil, in the pumping state, the electromagnets of the corresponding third oil circuit control valve 3 and first oil circuit control valve 4 are de-energized, so that A1 and C1 are disconnected from the oil tank.

[0140] During pumping, the energizing state of the second oil circuit control valve 5 is determined by the oil level in connecting chamber B. When the controller detects that connecting chamber B is low on oil and needs to be replenished, the right solenoid is energized, and the pressure oil source replenishes oil to connecting chamber B through the solenoid reversing valve. When the controller detects that connecting chamber B is high on oil and needs to be drained, the left solenoid is energized, and the connecting chamber drains oil to the tank through the solenoid reversing valve. If the controller detects that neither replenishment nor draining is necessary, both solenoids in the solenoid reversing valve are de-energized, disconnecting connecting chamber B from the pressure oil source and the tank.

[0141] When pumping stops, all electromagnets are de-energized.

[0142] Fourth embodiment:

[0143] Add damping to the oil inlet and outlet oil lines of the third oil circuit control valve 3 and the first oil circuit control valve 4, and add damping elements to the pressure oil source line and working oil line of the second oil circuit control valve 5 to control the oil flow rate. Figure 11 These damping elements can be used in combination as needed, for example, only a damping element can be installed in the oil circuit of oil port 1.

[0144] Fifth embodiment:

[0145] When the oil volume in the connecting chamber is too low, it is necessary to add oil from the oil tank. Considering that the oil in the oil tank is basically pressureless, in order to prevent the connecting chamber from generating negative pressure, the Figure 12 The scheme shown. Figure 12 The scheme shown is Figure 11 The difference is that the oil port 2 of the third oil control valve 3 and the first oil control valve 4 is connected to a pressurized oil source. Generally, a lower pressure oil source can be used, as long as the connecting chamber does not generate negative pressure. This pressurized oil source can be obtained by various means, such as the charge pump pressure of a closed pump or the pressure reduced by a pressure reducing valve. Figure 12 The damping in can also be used in combination, and of course no damping can be added at all.

[0146] Sixth embodiment:

[0147] Replace with a three-position four-way solenoid reversing valve Figure 12 The third oil circuit control valve 3 and the first oil circuit control valve 4 in the embodiment of the present invention can reduce the valve component cost and simplify the system. Figure 13 As shown. Figure 13 In the figure, the right electromagnet of the third oil circuit control valve 3 is energized, which is equivalent to Figure 12 The two-position two-way solenoid valve on the left side (i.e. Figure 12 The first oil circuit control valve 4 shown in the figure is energized, and the two-position two-way solenoid valve on the right (i.e. Figure 12 The third oil circuit control valve 3) shown in FIG is in a power-off state; accordingly, Figure 13The left electromagnet of the third oil circuit control valve 3 shown in FIG is energized, which is equivalent to Figure 12 The two-position two-way solenoid valve on the left side (i.e. Figure 12 The first oil circuit control valve 4 shown in the figure loses power, and the two-position two-way solenoid valve on the right (i.e. Figure 12 The third oil circuit control valve 3) shown in FIG is energized; Figure 13 The left and right electromagnets of the third oil circuit control valve 3 shown in FIG are both de-energized, which is equivalent to Figure 12 The third oil circuit control valve 3 and the first oil circuit control valve 4 are both in the power-off state.

[0148] Similarly, damping elements can be added to the working oil circuits of the P oil port and the A port of the third oil circuit control valve 3 to control the oil flow rate.

[0149] The T port of the third oil circuit control valve 3 may also be connected to a low-pressure oil source instead of the oil tank, so as to avoid excessively low pressure in the communicating chamber due to poor oil suction from the oil tank.

[0150] In summary, this application proposes a hydraulic control system and control logic, which uses three electromagnetic reversing valves to respectively control the oil replenishment and oil drain of each connecting chamber of the oil cylinder, which can effectively adjust the oil volume of the connecting chamber. Under various working conditions, it can effectively prevent the abnormal changes or lack of coordination in the oil volume of the connecting chamber, which may lead to the two cylinder strokes not meeting the requirements, cylinder blockage, cylinder collision, excessive pressure, etc., so that the pumping equipment can work normally. In addition, a method for controlling the oil volume of the passive connecting chamber (i.e., connecting to a low-pressure oil source) is also proposed. The low-pressure oil source is connected to prevent the passive connecting chamber from having too low a pressure in the connecting chamber due to poor oil replenishment, which may cause bubbles and cavitation.

[0151] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0152] In this application, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0153] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0154] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. The hydraulic system of concrete pumping equipment is characterized by: The concrete pumping equipment hydraulic system includes: The pumping cylinder group includes a chamber A as a rodless chamber, a chamber B as a rod chamber, and a chamber C as a piston rod chamber; Cylinder control hydraulic system, used to select the chamber as the working chamber and start and stop control of concrete pumping equipment; A hydraulic chamber auxiliary control hydraulic system is used to control the oil amount in the chamber serving as the communicating chamber in the pumping cylinder group in a pumping working state to be stable, and comprises an A chamber connecting oil circuit connected to the A chamber and provided with a first oil circuit control valve (4); a B chamber connecting oil circuit connected to the B chamber and provided with a second oil circuit control valve (5); and a C chamber connecting oil circuit connected to the C chamber and provided with a third oil circuit control valve (3). Each chamber in the pumping cylinder group is provided with an oil level detection element for detecting whether the oil level in the chamber is too much or too little. The hydraulic chamber auxiliary control hydraulic system includes a controller configured as follows: Determining that the controlled concrete pumping equipment is started and is in a pumping working state; Regarding the A chamber, B chamber and C chamber, the working chamber for connecting the working pressure oil and the main communication chamber for pushing the piston in reverse synchronization are respectively determined; obtaining an oil level detection signal from the oil level detection element in the main communicating chamber, and controlling the oil circuit control valve in the chamber connecting oil circuit corresponding to the main communicating chamber accordingly, so that the main communicating chamber performs corresponding oil replenishment or oil draining through the corresponding chamber connecting oil circuit; Furthermore, the controller is further configured to: Controlling to disconnect the chamber connecting oil circuit corresponding to the working chamber; Furthermore, the controller is further configured to: Determine the passively connected cavity without load drive among the cavity A, cavity B, and cavity C; The chamber corresponding to the passive communication chamber is controlled to connect to the oil circuit to return oil or to connect to a low-pressure oil source.

2. The hydraulic system of concrete pumping equipment according to claim 1, characterized in that: In the chamber connecting oil circuit corresponding to the passive communicating chamber, the oil inlet of the oil circuit control valve is connected to the oil supply circuit of the oil replenishment pump.

3. The hydraulic system of concrete pumping equipment according to claim 1, characterized in that: The controller is further configured to: Determining that the controlled concrete pumping equipment stops working; The plurality of oil circuit control valves are controlled so that all the chamber connection oil circuits are disconnected.

4. The hydraulic system for concrete pumping equipment according to any one of claims 1 to 3, characterized in that: The first oil circuit control valve (4), the second oil circuit control valve (5) and the third oil circuit control valve (3) are all electromagnetic reversing valves and communicate with the controller respectively.

5. The hydraulic system of concrete pumping equipment according to claim 4, characterized in that: The pumping cylinder group comprises a first pumping cylinder (1) and a second pumping cylinder (2) arranged in parallel, wherein the A chamber connecting oil circuit, the B chamber connecting oil circuit and the C chamber connecting oil circuit are respectively and individually connected to the A chamber, the B chamber and the C chamber of any one of the first pumping cylinder (1) and the second pumping cylinder (2), or the A chamber connecting oil circuit, the B chamber connecting oil circuit and the C chamber connecting oil circuit are respectively and simultaneously connected to the A chamber, the B chamber and the C chamber of the first pumping cylinder (1) and the second pumping cylinder (2).

6. The hydraulic system of concrete pumping equipment according to claim 4, characterized in that: The first oil circuit control valve (4), the second oil circuit control valve (5) and the third oil circuit control valve (3) are all three-position four-way reversing valves.

7. The hydraulic system of concrete pumping equipment according to claim 4, characterized in that: The oil cylinder control hydraulic system is configured to maintain the B chamber as the main communicating chamber in the pumping working state, the first oil circuit control valve (4) and the third oil circuit control valve (3) are both two-position two-way reversing valves, and the second oil circuit control valve (5) is a three-position four-way reversing valve.

8. The hydraulic system of concrete pumping equipment according to claim 7, characterized in that: The first oil circuit control valve (4) and the third oil circuit control valve (3) are integrated into a three-position four-way reversing valve.

9. The hydraulic system of concrete pumping equipment according to claim 1, characterized in that: A damping element (6) is provided in the chamber connecting oil circuit.

10. Concrete pumping equipment, characterized in that, The concrete pumping equipment includes the concrete pumping equipment hydraulic system according to any one of claims 1 to 9.

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