Forklift hydraulic control method for overturning large components

Abstract

The present invention discloses a forklift hydraulic system and control method for flipping large components, including an electric control handle, and a rotating mechanism, a horizontal moving cylinder and a clamping cylinder installed on a forklift attachment. The clamping cylinder and the rotating mechanism are connected in sequence through an integrated valve block, a main multi-way valve and a hydraulic oil tank to form respective hydraulic circuits, respectively clamping and rotating the large component; the main multi-way valve and the horizontal moving cylinder are connected to form a hydraulic circuit to center the large component on the forklift attachment; the signal end of the electric control handle is electrically connected to the integrated valve block and the main multi-way valve respectively. The present application adopts a forklift to realize the transport operation of the large component, and realizes the centering, clamping and flipping operations thereof as well as the rapid short-distance transfer. It ensures that the center of gravity of the large component remains in the middle during the flipping and other operations, and does not generate safety risks such as deflection, irregular shaking, and sudden impact.

Description

Technical Field

[0001] The invention relates to the technical field of transport tool vehicles, and in particular to a forklift hydraulic control method for overturning large components. Background Art

[0002] Precast concrete parts (components) refer to concrete products that are processed and produced in a standardized and mechanized manner in a factory. With the continuous development of the construction industry, various precast concrete parts have been widely used in various buildings and play an important role in the national economy. For example, a large number of large cement precast parts are required for construction at tunnel construction sites, and transportation operations are required between different sites. For example, it is necessary to move the cement precast parts from a horizontal state to a vertical state to facilitate transportation, installation, loading and unloading, and other easy-to-operate positions. At present, cranes or cranes are mostly used for lifting operations, but the use of cranes to change the placement of large cement precast parts is inefficient and difficult to operate; and after lifting, it will be limited by the site space and cannot be quickly transferred over short distances; in addition, the center of gravity position during operations such as flipping large components is uncontrollable, and there are safety risks such as deflection, irregular shaking, and sudden impact.

[0003] Therefore, the present invention uses a heavy-duty forklift to perform operations such as flipping and transporting the heavy-duty forklift, and the heavy-duty forklift industry involves lifting, lowering, tilting, side shifting, rotating, moving, turning, and other operations on the cargo device it carries, and these operations all need to be achieved through a set of hydraulic systems. Therefore, it is necessary to develop a hydraulic system for flipping large components for heavy-duty forklifts. Summary of the invention

[0004] The purpose of the present invention is to provide a forklift hydraulic system and control method for flipping large components, which is suitable for flipping operations of large components and realizes compaction, centering, smooth rotation, and rapid transfer operations of large components.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A forklift hydraulic system for flipping large components comprises an electric control handle, and a rotating mechanism, a horizontal moving cylinder and a clamping cylinder installed on the forklift attachment. The clamping cylinder and the rotating mechanism are connected in sequence through an integrated valve block, a main multi-way valve and a hydraulic oil tank to form respective hydraulic circuits, respectively clamping and rotating the large component; the main multi-way valve and the horizontal moving cylinder are connected to form a hydraulic circuit to center the large component on the forklift attachment; the signal end of the electric control handle is electrically connected to the integrated valve block and the main multi-way valve respectively.

[0007] The present application is an improvement on the existing forklift hydraulic system. The electric control handle, integrated valve block, main multi-way valve, hydraulic oil tank, oil cylinder, etc. are all already on the forklift, so the specific structure will not be described in detail here.

[0008] For example, the electric control handle is an integrated handle that integrates a hydraulic oil circuit and an electric circuit including a controller, which is an existing product available on the market, such as the electric control handle model DRFC15061 produced by Walvoil Company of Italy.

[0009] In a further solution, the rotating mechanism is a hydraulic rotating motor, the cylinder body of the horizontal moving cylinder is fixedly mounted on the forklift attachment, the piston rod is fixedly connected to the forklift frame, and the forklift attachment is movably mounted on the fork frame to be driven to rotate and move horizontally by the rotating mechanism and the horizontal moving cylinder respectively.

[0010] In a further solution, a centering positioning block is installed on the forklift attachment, and a position sensor for detecting the centering positioning block is installed on the fork frame; the output end of the position sensor is electrically connected to the electric control handle.

[0011] In a further solution, a cylinder stroke sensor is installed on the piston rod of the clamping cylinder for detecting the cylinder stroke, and the output end of the cylinder stroke sensor is electrically connected to the electric control handle.

[0012] The oil cylinder stroke sensor is also a known product and is commercially available, such as the WNAG series static magnetic grid oil cylinder stroke detector produced by Wuhan Yingjia Technology Development Co., Ltd.

[0013] According to a further solution, the integrated valve block includes a first oil circuit connecting the clamping cylinder and the main multi-way valve, and a second oil circuit connecting the rotating mechanism and the main multi-way valve; a hydraulic lock and a second three-position four-way solenoid valve are connected in series on the first oil circuit, and a first three-position four-way solenoid valve is connected in series on the second oil circuit; the first three-position four-way solenoid valve and the second three-position four-way solenoid valve are both electrically connected to the electric control handle.

[0014] In a further solution, the electric control handle is electrically connected to the integrated valve block, the main multi-way valve, the first three-position four-way solenoid valve, and the second three-position four-way solenoid valve through an integrated controller.

[0015] In a further solution, an adjustable overflow valve is connected in series to the oil inlet end of the second three-position four-way solenoid valve.

[0016] In a further solution, a pressure sensor is connected in series to the first oil circuit and the second oil circuit respectively, the output end of the pressure sensor is connected to a display screen, and the power supply end of the display screen is electrically connected to the integrated controller.

[0017] According to a further solution, the main multi-way valve includes at least two main valve plates, and a proportional solenoid valve is connected in series to the power supply end of each main valve plate to control the working position of its valve core; the two working oil ports of one of the main valve plates are respectively connected to the two oil circuits in the integrated valve block; the two working oil ports of the other main valve plate are respectively connected to the rod chamber and rodless chamber of the horizontal moving cylinder.

[0018] In a further solution, the oil inlet of the main multi-way valve is connected to the hydraulic oil tank through a one-way valve, a variable pump, and an oil suction filter in sequence; and the signal end of the variable pump is connected to the signal end of the main multi-way valve.

[0019] The second invention object of the present invention is to provide the above-mentioned forklift hydraulic control method for overturning a large component, the steps of which are as follows:

[0020] Step 1: Connect the pressure signal end of the main valve plate in the main multi-way valve to the signal end of the variable pump, and feed back the pressure signal of the main valve plate to the variable pump at any time to control the speed of the variable pump and the output flow of the hydraulic oil. When working, the system main pressure is 225bar, the speed of the variable pump is controlled between 1800-1910r / min, and the output flow of the hydraulic oil is accurately controlled at 46±3L / min;

[0021] Step 2: Place the large component on the fork frame, operate the clamping button on the electric control handle, and a main valve plate in the main multi-way valve works to input the hydraulic oil to the integrated valve block; at the same time, the valve core of the second three-position four-way solenoid valve in the integrated valve block works to open the first oil circuit, and the hydraulic oil enters the clamping cylinder through the second three-position four-way solenoid valve and the hydraulic lock in turn, and the clamping cylinder acts to clamp the large component;

[0022] Step 3: When the cylinder stroke sensor arranged on the piston rod of the clamping cylinder detects that the cylinder stroke reaches the maximum value, a feedback signal is given to the integrated controller to disconnect the clamping signal of the electric control handle, the clamping cylinder stops working and the oil circuit is locked under the action of the hydraulic lock, so that it maintains the clamping force on the large component;

[0023] Step 4: The position sensor on the fork frame detects that the forklift attachment is not centered through the centering block, and sends the detection signal to the integrated controller. The integrated controller controls another main valve plate in the main multi-way valve to work, and inputs hydraulic oil to the horizontal moving cylinder. The horizontal moving cylinder drives the forklift attachment and large components to move horizontally on the fork frame, so that they are centered in real time;

[0024] Step 5: When the rotary button on the electric control handle is operated, a main valve piece in the main multi-way valve works to input the hydraulic oil to the integrated valve block; at the same time, the valve core of the first three-position four-way solenoid valve in the integrated valve block works to open the second oil circuit, and the hydraulic oil enters the hydraulic rotary motor through the first three-position four-way solenoid valve, driving the forklift attachment to perform a flip operation with the large component.

[0025] The pressure sensor, position sensor, proportional solenoid valve, hydraulic lock, adjustable relief valve, one-way valve, three-position four-way solenoid valve, integrated controller, etc. in the present invention are all products known in the art and can be purchased commercially. The present invention selects products of corresponding models according to actual needs and directly applies them to the technology of the present application without involving improvements to their internal structure, function, principle, etc. The integrated controller is the MC43 integrated controller of Parker Company.

[0026] Compared with existing products, this product has the following advantages:

[0027] 1. This application uses a forklift to transfer large components and flip them over, which facilitates transportation, installation, loading and unloading operations, is highly efficient and safe, and can achieve rapid short-distance transfer.

[0028] This application is an improvement on the existing forklift hydraulic system. It innovatively applies the electric control handle, integrated valve block, main multi-way valve, hydraulic oil tank, oil cylinder and other equipment already on the forklift to the forklift used for flipping large components, so as to realize the centering, pressing and flipping operations of large components and fast short-distance transfer. It ensures that the center of gravity of large components remains in the middle during flipping and other operations, and does not cause safety risks such as deflection, irregular shaking, and sudden impact.

[0029] 2. In the present application, a centering positioning block is installed on the forklift attachment, and a position sensor for detecting the position of the centering positioning block is installed on the fork frame to ensure that the forklift attachment is located in the center of the fork frame to avoid unsafe situations caused by unbalanced loading; that is, the centering positioning block and the position sensor interact with each other, and the large component is adjusted to be centered on the fork frame in real time through the horizontal moving cylinder, which is beneficial to the safety of high-position lifting and flipping of large components and improves the longitudinal stability of the entire vehicle.

[0030] 3. This application uses a heavy-duty forklift controlled by a hydraulic system to transport large components, which is highly efficient and can achieve fast and reliable compaction, rotation and transfer operations of large components.

[0031] 4. This application uses an integrated controller to control the integrated valve block and the main multi-way valve to realize the opening and closing of each oil circuit, and accurately control the operation of the clamping cylinder, hydraulic rotary motor, and horizontal moving cylinder.

[0032] 5. This application collects the pressure generated by the loads of the two main valve plates on the main multi-way valve and feeds it back to the variable pump, and then controls the flow of the hydraulic oil through the flow valve inside it, that is, controls the speed and output flow of the variable pump, so that the flipping and transfer of large components are more stable.

[0033] 6. In the present application, the electric control handle, the integrated controller and the display screen are controlled in a coordinated manner. The operating signal of the electric control handle accurately controls the operation of the valve core of each oil valve through the integrated controller. The display screen can display the oil pressure of the two oil circuits in the integrated valve block in real time, thereby enabling real-time monitoring of the action of the clamping cylinder, making the identification of the operating status safer and more efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the hydraulic system of this application,

[0035] Figure 2 Schematic diagram of the main multi-way valve in this application,

[0036] The solid lines in the figure are oil circuits, and the dotted lines are circuits or signal lines. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Embodiment 1:

[0039] like Figure 1 As shown: a forklift hydraulic system for flipping large components, including an electric control handle 10, and a rotating mechanism, a horizontal moving cylinder 6 and a clamping cylinder 14 installed on the forklift attachment. The clamping cylinder 14 and the rotating mechanism are connected in sequence through an integrated valve block 16, a main multi-way valve 2 and a hydraulic oil tank 1 to form respective hydraulic circuits, respectively clamping and rotating the large component; the main multi-way valve 2 and the horizontal moving cylinder 6 are connected to form a hydraulic circuit to center the large component on the forklift attachment; the signal end of the electric control handle 10 is electrically connected to the integrated valve block 16 and the main multi-way valve 2 respectively.

[0040] In a further solution, the rotating mechanism is a hydraulic rotating motor 13, the cylinder body of the horizontal moving cylinder 6 is fixedly mounted on the forklift attachment, the piston rod is fixedly connected to the forklift frame, and the forklift attachment is movably mounted on the fork frame 7 to be driven to rotate and move horizontally by the rotating mechanism and the horizontal moving cylinder 6 respectively.

[0041] Since the forklift attachment is movably mounted on the fork frame, the hydraulic rotary motor 13 and the horizontal moving cylinder 6 are mounted on the forklift attachment, and the large component is loaded on the forklift attachment. Therefore, when the hydraulic rotary motor 13 is working, it will rotate with the forklift attachment and the large component, and when the horizontal moving cylinder 6 is working, it will move horizontally with the forklift attachment and the large component to adjust its position in the middle of the fork frame, so that the center of gravity can be maintained without tilting during lifting or rotation.

[0042] In a further solution, a centering positioning block 8 is installed on the forklift attachment, and a position sensor 9 for detecting the centering positioning block 8 is installed on the fork frame 7; the output end of the position sensor 9 is electrically connected to the electric control handle 10.

[0043] The centering positioning block 8 and the position sensor 9 interact with each other to keep the large component centered on the fork frame in real time through the horizontal movement of the cylinder, which is beneficial to the safety of the high-position lifting and turning of the large component, prevents it from being overloaded, improves the longitudinal stability of the whole vehicle, and realizes automatic centering adjustment.

[0044] This application is an improvement on the existing forklift hydraulic system, in which the electric control handle, integrated valve block, main multi-way valve, hydraulic oil tank, oil cylinder, etc. are all existing equipment on the forklift. This embodiment innovatively applies them together to the forklift used for flipping large components, realizing the centering, pressing and flipping operations of large components and fast short-distance transfer. It ensures that the center of gravity of large components remains in the middle during flipping and other operations, and does not cause safety risks such as deflection, irregular shaking, and sudden impact.

[0045] For example, the electric control handle is an integrated handle that integrates a hydraulic oil circuit and an electric circuit including a controller, and is an existing product available on the market, such as the electric control handle model DRFC15061 produced by Italy's Walvoil company; the integrated controller is Parker's MC43 integrated controller; the cylinder stroke sensor is the WNAG series static magnetic grid cylinder stroke detector produced by Wuhan Yingjia Technology Development Co., Ltd.

[0046] In a further solution, a cylinder stroke sensor 15 is installed on the piston rod of the clamping cylinder 14 for detecting the cylinder stroke, and the output end of the cylinder stroke sensor 15 is electrically connected to the electric control handle 10. The cylinder stroke sensor detects the cylinder stroke, and when the clamping cylinder reaches the maximum stroke, the signal is fed back to the integrated controller and the clamping signal of the electric control handle is disconnected, the clamping cylinder stops working and locks the oil circuit under the action of the hydraulic lock, so that it maintains the clamping force on the large component, that is, it is in the state of clamping the large component without moving.

[0047] In a further solution, the integrated valve block 16 includes a first oil circuit connecting the clamping cylinder 14 and the main multi-way valve 2, and a second oil circuit connecting the rotating mechanism and the main multi-way valve 2; the first oil circuit is connected in series with a hydraulic lock 161 and a second three-position four-way solenoid valve 163, and the second oil circuit is connected in series with a first three-position four-way solenoid valve 162; the first three-position four-way solenoid valve 162 and the second three-position four-way solenoid valve 163 are both electrically connected to the electric control handle 10.

[0048] In a further solution, the electric control handle 10 is electrically connected to the integrated valve block 16, the main multi-way valve 2, the first three-position four-way solenoid valve 162, and the second three-position four-way solenoid valve 163 through the integrated controller 11.

[0049] In a further solution, an adjustable overflow valve 164 is connected in series to the oil inlet end of the second three-position four-way solenoid valve 163 .

[0050] The electric control handle 10 outputs an action signal, and the second three-position four-way solenoid valve 163 works, and its valve core is in the right position, opening the first oil circuit in the second three-position four-way solenoid valve 163, and the main multi-way valve 2 supplies oil to the first oil circuit in the integrated valve block 16, specifically entering from the E5 port of the integrated valve block 16, passing through the adjustable relief valve 164, the second three-position four-way solenoid valve 163, and the hydraulic lock 161, and then entering the rodless chamber of the clamping cylinder 14 from the F4 port on the integrated valve block 16, pushing the piston rod of the clamping cylinder 14 to move. At this time, the rod chamber of the clamping cylinder 14 returns oil to the F3 port on the integrated valve block 16, and then passes through the hydraulic lock 161, the second three-position four-way solenoid valve 163, and flows back to the T1 port of the integrated valve block 16, and directly flows back to the hydraulic oil tank 1.

[0051] If the electric control handle 10 is released, the second three-position four-way solenoid valve 163 does not work, the valve core is in the middle position and the working oil port is closed, and the clamping cylinder locks the oil circuit under the action of the hydraulic lock 161 in the integrated valve block 16, preventing the circuit oil from flowing, and the clamping cylinder stops moving.

[0052] If the electric control handle 10 is not released at this time, the second three-position four-way solenoid valve 163 continues to work, but after the piston rod of the clamping cylinder moves to a certain position, the cylinder stroke sensor 15 will work and send a detection signal to the integrated controller. The integrated controller then drives the electric control handle 10 to disconnect the working signal from the second three-position four-way solenoid valve 163, and the second three-position four-way solenoid valve 163 does not work. The clamping cylinder 14 also locks the oil circuit under the action of the hydraulic lock 161, ensuring that large components will not be crushed while maintaining a certain clamping force.

[0053] In a further solution, a pressure sensor 17 is connected in series to the first oil circuit and the second oil circuit respectively, the output end of the pressure sensor 17 is connected to the display screen 12, and the power supply end of the display screen 12 is electrically connected to the integrated controller 11.

[0054] The pressure sensor 17 transmits the oil pressure of the first oil circuit and the second oil circuit in the integrated valve block to the display screen 12 through the wiring harness in real time, and monitors in real time to provide a control basis.

[0055] Further solutions, such as Figure 2 As shown, the main multi-way valve 2 includes a first main valve plate 21 and a second main valve plate 23. The power supply end of the first main valve plate 21 is connected in series with a first proportional solenoid valve 22 to control the working position of its valve core, and the power supply end of the second main valve plate 23 is connected in series with a second proportional solenoid valve 24 to control the working position of its valve core; the main multi-way valve 2 is provided with an oil inlet port P1, working oil ports E1 and E2, working oil ports C1 and C2, an oil return port T2, an oil drain port T3, and a signal port LS1. The two working oil ports of the first main valve plate 21 are connected to the two oil circuits in the integrated valve block 16 through ports E1 and E2 respectively; the two working oil ports of the second main valve plate 23 are connected to the rod chamber and rodless chamber of the horizontal moving oil cylinder 6 through ports C1 and C2 respectively.

[0056] In a further solution, the oil inlet of the main multi-way valve 2 is connected to the hydraulic oil tank 1 through a one-way valve 3, a variable pump 5, and an oil suction filter 4 in sequence; and the signal end of the variable pump 5 is connected to the signal end of the main multi-way valve 2.

[0057] When the vehicle is working, the variable pump 5 absorbs clean hydraulic oil from the hydraulic oil tank 1 through the oil suction filter 4, and then enters the main multi-way valve 2 through the one-way valve 3. The pressure generated by the main valve plate load on the main multi-way valve 2 is fed back to the variable pump 5, and then the motor speed is adjusted to reasonably control the speed and output flow of the variable pump 5.

[0058] A variable displacement pump is a pump with variable displacement and is also an existing product available on the market. When a certain circuit in the system is working, the load will feedback an LS signal (that is, the load amount). When the pressure exceeds the high-pressure oil pressure of the oil pump, the flow rate to the load is increased by controlling the valve core of the internal flow valve.

[0059] The main working process of the hydraulic system of this application is as follows:

[0060] This embodiment is provided with four pressing oil cylinders. Figure 1 As shown:

[0061] When the vehicle is working, the variable pump 5 absorbs clean hydraulic oil from the hydraulic oil tank 1 through the oil suction filter 4, and enters the main multi-way valve 2 through the one-way valve 3. The pressure generated by the load of the two main valve plates 21 and 23 on the main multi-way valve 2 is fed back to the LS port on the variable pump 5 through the LS1 port on the main multi-way valve 2, and together with the motor, the speed and output flow of the variable pump 5 are reasonably controlled. The electric control handle 10 is operated to control the action, as follows:

[0062] 1. When the clamping button on the electric control handle 10 is operated, the electric signal is transmitted to the coil on the second three-position four-way solenoid valve 163 and the first proportional solenoid valve 22 on the main multi-way valve 2 through the integrated controller 11, and the second three-position four-way solenoid valve 163 works in the right position to open the first oil circuit; the first proportional solenoid valve 22 controls the first main valve plate 21 to work in the lower position, at this time, the hydraulic oil through the one-way valve 3 enters from the P1 port on the main multi-way valve 2, and then passes through the first main valve plate 21 and then supplies oil to the E5 port on the integrated valve block 16 through the E2 port, and passes through the K of the adjustable relief valve 164 on the first oil circuit. 11, K2 port, and then supply the K3 port and K6 port of the second three-position four-way solenoid valve 163 to enter the hydraulic lock 161, and finally come out from the F4 port on the integrated valve block 16 and then divided into four paths, respectively supplying the rodless chambers (X8, X6, X4, X1 ports) of the four clamping cylinders 14, pushing the piston rod of the clamping cylinder 14 to move. At this time, the rod chambers (X7, X5, X3, X2 ports) of the four clamping cylinders 14 return oil to the F3 port on the integrated valve block 16, and then return to the T1 port of the integrated valve block 16 through the hydraulic lock 161 and the second three-position four-way solenoid valve 163, and directly return to the hydraulic oil tank 1.

[0063] If the electric control handle 10 is released, the second three-position four-way solenoid valve 163 does not work, the valve core is in the middle position and the working oil port is closed, and the four oil cylinders clamping cylinder 14 locks the oil circuit under the action of the hydraulic lock 231 in the integrated valve block 16, and the clamping cylinders all stop moving and maintain the clamping state.

[0064] At this time, if the electric control handle 10 is not released, the second three-position four-way solenoid valve 163 continues to work, but after the piston rod of the clamping cylinder moves to a certain position, the cylinder stroke sensor 15 will work and send a detection signal to the integrated controller. The integrated controller then drives the electric control handle 10 to disconnect the working signal from the second three-position four-way solenoid valve 163, that is, the electric control handle 10 signal is automatically stopped. At this time, the second three-position four-way solenoid valve 163 does not work, and the clamping cylinder 14 also locks the oil circuit under the action of the hydraulic lock 161. The clamping cylinders all stop moving and maintain a clamping state, ensuring that large components will not be crushed while maintaining a certain clamping force.

[0065] 2. When the electric control handle 10 outputs an action signal to make the valve core of the second three-position four-way solenoid valve 163 work in the left position, the oil circuit is switched, and the hydraulic oil in the main multi-way valve 2 enters the E5 port of the integrated valve block 16 through the E2 port, and then enters the hydraulic lock 161 through the K11 and K2 ports of the adjustable relief valve 164, the K3 and K5 ports of the second three-position four-way solenoid valve 163, and finally comes out from the F3 port on the integrated valve block 16 and is divided into four routes, respectively supplying the rod chambers (X7, X5, X3, and X2 ports) of the four clamping cylinders 14 to push the piston rod of the clamping cylinder 14 to move. At this time, the rodless chambers (X8, X6, X4, and X1 ports) of the four clamping cylinders 14 return oil to the F4 port on the integrated valve block 16, and then flow back to the T1 port of the integrated valve block 16 through the hydraulic lock 161 and the second three-position four-way solenoid valve 163, and directly return to the hydraulic oil tank 1. The clamping cylinder 14 releases the operation of the large preform, and the above realizes the automatic control of the clamping and releasing action of the clamping cylinder.

[0066] 3. When the button of the rotation function corresponding to the electric control handle 10 is operated, the electric signal is transmitted to the coil on the first three-position four-way solenoid valve 162 and the first proportional solenoid valve 22 on the main multi-way valve 2 through the integrated controller 11, and the first three-position four-way solenoid valve 162 works in the right position to open the second oil circuit; the first proportional solenoid valve 22 in the main multi-way valve 2 controls the first main valve plate 21 to work in the upper position. The hydraulic oil is directly connected to the E3 port on the integrated valve block 16 through the E1 port, and then directly connected to the hydraulic rotary motor 13 from the F2 port of the integrated valve block 16 through the K7 port and K10 port on the first three-position four-way solenoid valve 162, and the rotary torque of the hydraulic rotary motor 13 is used to drive the forklift attachments and large components to rotate together.

[0067] As above, when the first three-position four-way solenoid valve 162 works in the left position, the hydraulic rotary motor 13 realizes reverse rotation.

[0068] 4. When the centering button on the electric control handle 10 is operated, the electrical signal transmits the action execution signal to the second proportional solenoid valve 24 on the main multi-way valve 2 through the integrated controller 11, and the second main valve plate 23 works. The hydraulic oil is supplied to the horizontal moving cylinder 6 from the C1 port or C2 port of the second main valve plate 23 through the second main valve plate 23. At the same time, the centering positioning block 8 and the position sensor 9 interact with each other to keep the large component centered on the forklift attachment in real time, which is beneficial to the safety of high-position lifting of large components, without unbalanced loading, improving the longitudinal stability of the whole vehicle, and automatically adjusting the centering.

[0069] A pressure sensor 17 is connected in series to the first oil circuit and the second oil circuit in the integrated valve block 16 respectively. The pressure sensor 17 transmits the oil pressure of the first oil circuit and the second oil circuit in the integrated valve block in real time through the wiring harness and displays it on the display screen 12 for real-time monitoring to provide a control basis. The electric control handle 10, the integrated controller 11, and the display screen 12 are controlled in coordination with each other, which is more energy-saving and has higher operating efficiency.

[0070] Embodiment 2:

[0071] A forklift hydraulic control method for turning over a large component comprises the following steps:

[0072] Step 1: Connect the pressure signal end of the main valve plate in the main multi-way valve 2 to the signal end of the variable pump 5, and feed back the pressure signal of the main valve plate to the variable pump at any time to control the speed of the variable pump and the output flow of the hydraulic oil; when working, the system main pressure is 225bar, the speed of the variable pump is controlled between 1800-1910r / min, and the output flow of the hydraulic oil is accurately controlled at 46±3L / min;

[0073] Step 2: Place the large component on the fork frame, operate the clamping button on the electric control handle 10, a main valve plate in the main multi-way valve 2 works, and the hydraulic oil is input to the integrated valve block 16; at the same time, the valve core of the second three-position four-way solenoid valve 163 in the integrated valve block 16 works, opens the first oil circuit, and the hydraulic oil enters the clamping cylinder 14 through the second three-position four-way solenoid valve 163 and the hydraulic lock 161 in sequence, and the clamping cylinder is actuated to clamp the large component;

[0074] Step 3: When the cylinder stroke sensor 15 arranged on the piston rod of the clamping cylinder 14 detects that the cylinder stroke reaches the maximum value, a feedback signal is given to the integrated controller 11 to disconnect the clamping signal of the electric control handle 10, and the clamping cylinder 14 stops working and locks the oil circuit under the action of the hydraulic lock 161, so that it maintains the clamping force on the large component;

[0075] Step 4: The position sensor 9 on the fork frame detects that the forklift attachment is not centered through the centering positioning block 8, and sends a detection signal to the integrated controller 11. The integrated controller 11 controls another main valve plate in the main multi-way valve 2 to work, and inputs hydraulic oil to the horizontal movement cylinder 6. The horizontal movement cylinder 6 drives the forklift attachment and the large component to move horizontally on the fork frame, so that they are centered in real time;

[0076] Step 5: When the rotary button on the electric control handle 10 is operated, a main valve plate in the main multi-way valve 2 works to input the hydraulic oil to the integrated valve block 16; at the same time, the valve core of the first three-position four-way solenoid valve 162 in the integrated valve block 16 works to open the second oil circuit, and the hydraulic oil enters the hydraulic rotary motor 13 through the first three-position four-way solenoid valve 162, driving the forklift attachment to perform a flip operation with the large component.

[0077] Although this specification is described according to implementation modes, not every implementation mode includes only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0078] Therefore, the above description is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application; that is, all equivalent changes made according to the scope of the claims of the present application are within the protection scope of the claims of the present application.

Claims

1. A forklift hydraulic control method for turning over a large component, characterized in that: The following steps are involved: Step 1: Connect the pressure signal end of the main valve plate in the main multi-way valve (2) to the signal end of the variable pump (5), and feed back the pressure signal of the main valve plate to the variable pump at any time, so as to control the speed of the variable pump and the output flow rate of the hydraulic oil; Step 2: Place the large component on the fork frame, operate the clamping button on the electric control handle (10), and a main valve plate in the main multi-way valve (2) operates to input hydraulic oil to the integrated valve block (16); at the same time, the valve core of the second three-position four-way solenoid valve (163) in the integrated valve block (16) operates to open the first oil circuit, and the hydraulic oil enters the clamping cylinder (14) in sequence through the second three-position four-way solenoid valve (163) and the hydraulic lock (161), and the clamping cylinder is actuated to clamp the large component; Step 3: When the cylinder stroke sensor (15) disposed on the piston rod of the clamping cylinder (14) detects that the cylinder stroke has reached the maximum value, a feedback signal is given to the integrated controller (11) to disconnect the clamping signal of the electric control handle (10), and the clamping cylinder (14) stops working and locks the oil circuit under the action of the hydraulic lock (161), so that the clamping force on the large component is maintained; Step 4: The position sensor (9) on the fork frame detects that the forklift attachment is not centered through the centering positioning block (8), and sends a detection signal to the integrated controller (11). The integrated controller (11) controls another main valve plate in the main multi-way valve (2) to work, and inputs hydraulic oil to the horizontal movement cylinder (6). The horizontal movement cylinder (6) drives the forklift attachment and the large component to move horizontally on the fork frame, so that they are centered in real time. Step 5: When the rotary button on the electric control handle (10) is operated, a main valve plate in the main multi-way valve (2) operates to input the hydraulic oil to the integrated valve block (16); at the same time, the valve core of the first three-position four-way solenoid valve (162) in the integrated valve block (16) operates to open the second oil circuit, and the hydraulic oil enters the hydraulic rotary motor (13) through the first three-position four-way solenoid valve (162), driving the forklift attachment to carry the large component to perform a flip operation.

2. The forklift hydraulic control method according to claim 1, characterized in that: The clamping oil cylinder (14) and the hydraulic rotating motor (13) are connected in sequence through the integrated valve block (16), the main multi-way valve (2) and the hydraulic oil tank (1) to form respective hydraulic circuits, respectively enabling the large component to be clamped and rotated; the main multi-way valve (2) and the horizontal movement oil cylinder (6) are connected to form a hydraulic circuit to center the large component on the forklift attachment; and the signal end of the electric control handle (10) is electrically connected to the integrated valve block (16) and the main multi-way valve (2) respectively.

3. The forklift hydraulic control method according to claim 1, characterized in that: The integrated valve block (16) comprises a first oil circuit connecting the clamping oil cylinder (14) and the main multi-way valve (2), and a second oil circuit connecting the rotating mechanism and the main multi-way valve (2); a hydraulic lock (161) and a second three-position four-way solenoid valve (163) are connected in series to the first oil circuit, and a first three-position four-way solenoid valve (162) is connected in series to the second oil circuit; the first three-position four-way solenoid valve (162) and the second three-position four-way solenoid valve (163) are both electrically connected to the electric control handle (10).

4. The forklift hydraulic control method according to claim 3, characterized in that: An adjustable overflow valve (164) is connected in series to the oil inlet end of the second three-position four-way solenoid valve (163); a pressure sensor (17) is connected in series to the first oil circuit and the second oil circuit respectively; an output end of the pressure sensor (17) is connected to a display screen (12); and a power supply end of the display screen (12) is electrically connected to an integrated controller (11).

5. The forklift hydraulic control method according to claim 1, characterized in that: The cylinder body of the horizontal moving oil cylinder (6) is fixedly mounted on the forklift attachment, and the piston rod is fixedly connected to the forklift frame; the forklift attachment is movably mounted on the fork frame (7) and is driven to rotate and move horizontally by the hydraulic rotary motor (13) and the horizontal moving oil cylinder (6) respectively.

6. The forklift hydraulic control method according to claim 1, characterized in that: The centering positioning block (8) is mounted on the forklift attachment, and the position sensor (9) is mounted on the fork frame (7); the output end of the position sensor (9) is electrically connected to the electric control handle (10).

7. The forklift hydraulic control method according to claim 6, characterized in that: The electric control handle (10) is electrically connected to the integrated valve block (16), the main multi-way valve (2), the first three-position four-way solenoid valve (162), and the second three-position four-way solenoid valve (163) respectively through the integrated controller (11).

8. The forklift hydraulic control method according to claim 1, characterized in that: The main multi-way valve (2) comprises at least two main valve plates, and a proportional solenoid valve is connected in series to the power supply end of each main valve plate to control the working position of its valve core; the two working oil ports of one main valve plate are respectively connected to the two oil circuits in the integrated valve block (16); and the two working oil ports of the other main valve plate are respectively connected to the rod chamber and the rodless chamber of the horizontal moving cylinder (6).

9. The forklift hydraulic control method according to claim 1, characterized in that: The oil inlet of the main multi-way valve (2) is connected to the hydraulic oil tank (1) via a one-way valve (3), a variable pump (5) and an oil suction filter (4) in sequence.

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