Integrated valve group for electric forklift, hydraulic system and electric forklift

Abstract

The utility model discloses an integrated valve group for an electric forklift, a hydraulic system and the electric forklift. The integrated valve group comprises a main oil inlet A, a main oil outlet T and an overflow valve connected between the main oil inlet A and the main oil outlet T, and a first speed regulating valve, a second speed regulating valve, a first three-position four-way electromagnetic valve and a second three-position four-way electromagnetic valve are also connected between the main oil inlet A and the main oil outlet T. The utility model further discloses a hydraulic system comprising the integrated valve group and an electric forklift, independent movement of double pallet forks can be controlled by a single oil source, and the integrated valve group has the advantages of accurate flow and pressure control, energy conservation and convenience in space design.

Description

Technical Field

[0001] The utility model belongs to the technical field of electric forklift hydraulic systems, and in particular relates to an integrated valve group for an electric forklift and a hydraulic system containing the same, and also relates to an electric forklift containing the hydraulic system. Background Art

[0002] Heavy-duty electric forklifts are usually equipped with two forks, which require two independent oil cylinders to control the left and right movement of the forks. In the design of existing vehicles, the oil source required for the oil cylinders moving the two forks comes from two independent valve plates on the multi-way valve of the main hydraulic system. The secondary relief valve on the multi-way valve is required to control the pressure and flow required by the oil cylinders moving the forks. Such an oil circuit design needs to meet the high-pressure and high-flow requirements of the main hydraulic system on the one hand, and the low-pressure and low-flow requirements of the forks on the other hand, resulting in relatively large pressure loss and energy loss that cannot be accurately controlled.

[0003] In addition, the pipeline installation is relatively complicated, making it difficult to arrange the pipelines in the already compact vehicle body. For example, the main valve control oil port requires two pipelines to be connected from the vehicle body to the fork moving cylinder on the mast, and the integration is not high. Utility Model Content

[0004] In view of this, it is necessary for the utility model to provide an integrated valve group for an electric forklift. Through the design of the integrated valve group, a single oil source can be used to control the movement of two forks, and precise flow and pressure output can be achieved. In addition, the integrated valve group can shorten the pipeline, and the design integration within the entire vehicle is higher.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] The utility model discloses an integrated valve group for an electric forklift, comprising a main oil inlet A and a main oil outlet T and a relief valve connected between the main oil inlet A and the main oil outlet T; a first speed regulating valve, a second speed regulating valve, a first three-position four-way solenoid valve and a second three-position four-way solenoid valve are also connected between the main oil inlet A and the main oil outlet T;

[0007] The inlet B end of the first speed regulating valve and the inlet C end of the second speed regulating valve are respectively connected to the main oil inlet A;

[0008] The outlet of the first speed regulating valve is connected to the F1 end of the first three-position four-way solenoid valve, and the outlet of the second speed regulating valve is connected to the G1 end of the second three-position four-way solenoid valve;

[0009] The F2 end of the first three-position four-way solenoid valve and the G2 end of the second three-position four-way solenoid valve are respectively connected to the main oil outlet T;

[0010] The F3 end and F4 end of the first three-position four-way solenoid valve are connected to the L port and K port of the integrated valve group respectively, and the G3 end and G4 end of the second three-position four-way solenoid valve are connected to the J port and H port of the integrated valve group respectively.

[0011] The second aspect of the utility model discloses an electric forklift hydraulic system, which comprises the above-mentioned integrated valve group for the electric forklift.

[0012] In some specific embodiments, the electric forklift hydraulic system includes:

[0013] The aforementioned integrated valve group for electric forklifts;

[0014] A hydraulic oil source connected to a main oil outlet T of the integrated valve group for the electric forklift;

[0015] A power pump group, whose inlet is connected to the hydraulic oil source, and whose outlet is connected to the main oil inlet A of the integrated valve group for the electric forklift;

[0016] As well as the right fork moving cylinder and the left fork moving cylinder;

[0017] Among them, the L port and K port of the integrated valve group for electric forklift are respectively connected to the rodless chamber M port and the rod chamber N port of the right fork moving cylinder, and the J port and H port of the integrated valve group for electric forklift are respectively connected to the rod chamber P port and the rodless chamber Q port of the left fork moving cylinder.

[0018] In a further solution, the right fork moving cylinder is connected to the right fork, and the left fork moving cylinder is connected to the left fork.

[0019] In some specific implementations, the power pump assembly includes a motor and a gear pump, and the motor is connected to the gear pump.

[0020] In a further solution, the oil inlet of the gear pump is connected to the hydraulic oil source, and the oil outlet of the gear pump is connected to the main oil inlet A of the integrated valve group for the electric forklift.

[0021] In a further scheme, when the left position of the first three-position four-way solenoid valve is energized, the F1 end and the F4 end of the first three-position four-way solenoid valve are connected, the F3 end and the F2 end of the first three-position four-way solenoid valve are connected, the oil supply oil circuit is F1→F4→K→N, and the oil return oil circuit is M→L→F3→F2→T;

[0022] When the right position of the first three-position four-way solenoid valve is energized, the F1 end and the F3 end of the first three-position four-way solenoid valve are connected, the F4 end and the F2 end of the first three-position four-way solenoid valve are connected, the oil supply circuit is F1→F3→L→M, and the oil return circuit is N→K→F4→F2→T.

[0023] In a further scheme, when the left position of the second three-position four-way solenoid valve is energized, the G1 end and the G4 end of the second three-position four-way solenoid valve are connected, the G3 end and the G2 end of the second three-position four-way solenoid valve are connected, the oil supply oil circuit is G1→G4→H→Q, and the oil return oil circuit is P→J→G3→G2→T;

[0024] When the right position of the second three-position four-way solenoid valve is energized, the G1 end and G3 end of the second three-position four-way solenoid valve are connected, the G4 end and G2 end of the second three-position four-way solenoid valve are connected, the oil supply circuit is G1→G3→J→P, and the oil return circuit is Q→H→G4→G2→T.

[0025] The third aspect of the utility model discloses an electric forklift, comprising the electric forklift hydraulic system as described above.

[0026] Beneficial effects of the utility model:

[0027] The integrated valve group can realize single oil source control, achieve precise flow and pressure output, save pressure loss, and be more energy-efficient.

[0028] The hydraulic system formed by the integrated valve group makes it unnecessary for the main hydraulic system to anticipate the fork movement hydraulic module, making the control of the main hydraulic system simpler.

[0029] The hydraulic system with an independent single oil source device makes the vehicle layout more flexible and can make full use of the available space for independent layout. The system design is simpler and the integrated valve group can be arranged closer to the fork moving cylinder as needed, which can shorten the pipeline length and make function expansion easier to control. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic diagram of the principle of a hydraulic system 200 in a preferred embodiment of the present invention.

[0031] In the figure: 100-integrated valve group, 110-overflow valve, 120-first speed regulating valve, 130-second speed regulating valve, 140-first three-position four-way solenoid valve, 150-second three-position four-way solenoid valve; 200-hydraulic system, 210-hydraulic oil source, 220-motor, 230-gear pump, 240-right fork moving cylinder, 250-right fork, 260-left fork moving cylinder, 270-left fork. DETAILED DESCRIPTION

[0032] The integrated valve group and hydraulic system for the electric forklift provided by the utility model will be further described in detail below in conjunction with the accompanying drawings of the specification.

[0033] It should be noted that when a component is referred to as being "fixed to", "disposed on", or "installed on" another component, it can be directly on the other component or indirectly on the other component. However, when an element is referred to as being "connected to" or "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element. In addition, connection generally refers to the use for fixing, and the fixing here can be any conventional fixing method in the art, such as "threaded connection", "riveting", "welding", etc.

[0034] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings of the specification, and are only for the convenience of describing the embodiments of the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed or operate in a specific orientation, and therefore cannot be understood as a limitation on the utility model.

[0035] This embodiment provides an integrated valve group 100 for an electric forklift. Figure 1 As shown in , the integrated valve group 100 includes a relief valve 110, a first speed regulating valve 120, a second speed regulating valve 130, a first three-position four-way solenoid valve 140, and a second three-position four-way solenoid valve 150. The integrated valve group 100 includes a main oil inlet A and a main oil outlet T, and also includes a plurality of output ports leading to the actuator, which are L port, K ​​port, J port and K port in this embodiment.

[0036] The overflow valve 110 is connected between the main oil inlet A and the main oil outlet T of the integrated valve group 100, and is used to control the pressure required for the actuator (fork in this embodiment) to move. Figure 1 As shown in , the D end of the relief valve 110 is connected to the main oil inlet A, and the E end of the relief valve 110 is connected to the main oil outlet T.

[0037] Further, the inlet B end of the first speed regulating valve 120 and the inlet C end of the second speed regulating valve 130 are respectively connected to the main oil inlet A. The outlet of the first speed regulating valve 120 is connected to the F1 end of the first three-position four-way solenoid valve 140 , and the outlet of the second speed regulating valve 130 is connected to the G1 end of the second three-position four-way solenoid valve 150 .

[0038] Further, the F2 end of the first three-position four-way solenoid valve 140 and the G2 end of the second three-position four-way solenoid valve 150 are respectively connected to the main oil outlet T. The F3 end and the F4 end of the first three-position four-way solenoid valve 140 are respectively connected to the L port and the K port of the integrated valve group 100, and the G3 end and the G4 end of the second three-position four-way solenoid valve 150 are respectively connected to the J port and the H port of the integrated valve group 100.

[0039] The integrated valve group 100 realizes the switching and supply of different oil circuits by controlling the first three-position four-way solenoid valve 140 and the second three-position four-way solenoid valve 150, thereby realizing different actions of the actuator.

[0040] Please continue reading Figure 1 , Figure 1 , a hydraulic system 200 including an integrated valve assembly 100 is shown, and the hydraulic system 200 further includes a hydraulic oil source 210 , a motor 220 , a gear pump 230 , a right fork moving cylinder 240 , a right fork 250 , a left fork moving cylinder 260 and a left fork 270 .

[0041] Among them, in this embodiment, the hydraulic oil source 210 is an integrated oil tank, and the main oil outlet T of the integrated valve group 100 is connected to the hydraulic oil source 210; the motor 220 and the gear pump 230 are connected to form a power pump group to provide power for the hydraulic system 200 oil circuit, the oil inlet of the gear pump 230 is connected to the hydraulic oil source 210, and the oil outlet of the gear pump 230 is connected to the main oil inlet A of the integrated valve group 100.

[0042] Further, the right fork moving oil cylinder 240 is connected to the right fork 250, and the left fork moving oil cylinder 260 is connected to the left fork 270, respectively constituting the actuators of the hydraulic system 200. Specifically, the rodless chamber M port of the right fork moving oil cylinder 240 is connected to the L port of the integrated valve group 100, and its rod chamber N port is connected to the K port of the integrated valve group 100. The rod chamber P port of the left fork moving oil cylinder 260 is connected to the J port of the integrated valve group 100, and its rodless chamber Q port is connected to the H port of the integrated valve group 100.

[0043] During specific operation, when the driver needs to move the fork, he operates the switch on the integrated handle to start the motor 220, so that the gear pump 230 draws oil from the hydraulic oil source 210, and enters the integrated valve group 100 after pressurization. At the same time, the first three-position four-way solenoid valve 140 and the second three-position four-way solenoid valve 150 in the integrated valve group 100 are controlled to realize oil supply, and the overflow valve 110 controls the required pressure for the movement of the fork. After the high-pressure oil enters the integrated valve group 100, the movement of the fork is controlled, and a single oil source can be used to control the independent movement of the two forks.

[0044] Please combine Figure 1 , the working principle of the hydraulic system 200 in this embodiment is as follows:

[0045] 1. The right fork 250 moves left and right independently

[0046] When the driver presses the switch for the right fork 250 to move to the left, the motor 220 is powered on and starts to run, driving the gear pump 230 to run. The gear pump 230 draws oil from the hydraulic oil source 210, and after being pressurized by the gear pump 230, it is input into the integrated valve group 100. After the required pressure is precisely controlled by the relief valve 110, the high-pressure oil enters the inlet B end of the first speed regulating valve 120 and the inlet C end of the second speed regulating valve 130 respectively. When the driver presses the switch for the right fork 250 to move to the left, the left position solenoid valve of the first three-position four-way solenoid valve 140 is powered on, and the first three-position four-way solenoid valve 140 works in the left position, while the second three-position four-way solenoid valve 150 is not powered on at this time, and the second three-position four-way solenoid valve 150 is in the middle position, and the oil circuit is blocked. At this time, the oil circuit of the second speed regulating valve 130 is blocked. The first three-position four-way solenoid valve 140 is energized in the left position, and the F1 end and F4 end of the first three-position four-way solenoid valve 140 are connected, and the F3 end and F2 end are connected. All the oil is supplied to the right fork moving cylinder 240 through the first speed regulating valve 120 and the first three-position four-way solenoid valve 140. At this time, the oil supply circuit is F1→F4→K→N, and the oil enters the rod cavity of the right fork moving cylinder 240, pushing the piston rod inside the right fork moving cylinder 240 to move left, driving the right fork 250 to move left; at this time, the oil in the rodless cavity of the right fork moving cylinder 240 directly flows back to the hydraulic oil source 210 through the return oil circuit M→L→F3→F2→T, completing the leftward movement of the right fork 250.

[0047] The process of the right fork 250 moving to the right is similar to that of moving to the left. In short, when the driver presses the switch for the right fork 250 to move to the right, the oil circuit of the second three-position four-way solenoid valve 150 is open, and the first three-position four-way solenoid valve 140 works in the right position, with its F1 end and F3 end connected, and its F4 end and F2 end connected. At this time, the oil supply circuit is F1→F3→L→M, and the oil enters the rodless chamber of the right fork moving cylinder 240, pushing the piston rod inside the right fork moving cylinder 240 to move to the right, driving the right fork 250 to move to the right; at this time, the oil in the rod chamber of the right fork moving cylinder 240 directly flows back to the hydraulic oil source 210 through the return oil circuit N→K→F4→F2→T, completing the rightward movement of the right fork 250.

[0048] 2. The left fork 270 moves left and right independently

[0049] When the driver presses the switch for the left fork 270 to move to the left, the motor 220 is powered on and starts to run, driving the gear pump 230 to run. The gear pump 230 draws oil from the hydraulic oil source 210, and after being pressurized by the gear pump 230, it is input into the integrated valve group 100. After the required pressure is precisely controlled by the relief valve 110, the high-pressure oil enters the inlet B end of the first speed regulating valve 120 and the inlet C end of the second speed regulating valve 130 respectively. When the driver presses the switch for the left fork 270 to move to the left, the left position solenoid valve of the second three-position four-way solenoid valve 150 is powered on, and the second three-position four-way solenoid valve 150 works in the left position, while the first three-position four-way solenoid valve 140 is not powered on at this time, and the first three-position four-way solenoid valve 140 is in the middle position, and the oil circuit is blocked. At this time, the oil circuit of the first speed regulating valve 120 is blocked. The second three-position four-way solenoid valve 150 is energized in the left position, and the G1 end and G4 end of the second three-position four-way solenoid valve 150 are connected, and the G3 end and G2 end are connected, and all the oil is supplied to the left fork moving cylinder 260 through the second speed control valve 130 and the second three-position four-way solenoid valve 150. At this time, the oil supply circuit is G1→G4→H→Q, and the oil enters the rodless cavity of the left fork moving cylinder 260, pushing the piston rod inside the left fork moving cylinder 260 to move left, driving the left fork 270 to move left; at this time, the oil in the rod cavity of the left fork moving cylinder 260 directly flows back to the hydraulic oil source 210 through the return oil circuit P→J→G3→G2→T, completing the leftward movement of the left fork 270.

[0050] The process of the left fork 270 moving to the right is similar to that of the left fork. In short, when the driver presses the switch for the left fork 270 to move to the right, the oil circuit of the first three-position four-way solenoid valve 140 is blocked, and the second three-position four-way solenoid valve 150 works in the right position, with its G1 end and G3 end connected, and its G4 end and G2 end connected. At this time, the oil supply circuit is G1→G3→J→P, and the oil enters the rod chamber of the left fork moving cylinder 260, pushing the piston rod inside the left fork moving cylinder 260 to move to the right, driving the left fork 270 to move to the right; at this time, the oil in the rodless chamber of the left fork moving cylinder 260 directly flows back to the hydraulic oil source 210 through the return oil circuit Q→H→G4→G2→T, completing the rightward movement of the left fork 270.

[0051] 3. The left and right forks are extended or retracted at the same time

[0052] When the driver presses the switch to unfold the left and right forks at the same time, the high-pressure oil from the gear pump 230 enters the first speed regulating valve 120 and the second speed regulating valve 130. At this time, the first three-position four-way solenoid valve 140 works in the right position, and its F1 end is connected to the F3 end, and the F4 end is connected to the F2 end. The oil supply circuit of the first three-position four-way solenoid valve 140 is F1→F3→L→M, and oil enters the rodless chamber of the right fork moving cylinder 240, pushing the piston rod of the right fork moving cylinder 240 to move to the right, driving the right fork 250 to move to the right, that is, to move in the unfolding direction outside the vehicle body, and the oil in the rod chamber of the right fork moving cylinder 240 flows back to the hydraulic oil source 210 through the return oil circuit N→K→F4→F2→T. At the same time, the second three-position four-way solenoid valve 150 works in the left position, its G1 end is connected to the G4 end, and the G3 end is connected to the G2 end. The oil supply circuit of the second three-position four-way solenoid valve 150 is G1→G4→H→Q. The rodless chamber of the left fork moving cylinder 260 enters oil, pushing the piston rod of the left fork moving cylinder 260 to move left, driving the left fork 270 to move left, that is, to move in the direction of unfolding outside the vehicle body, and the oil in the rod chamber of the left fork moving cylinder 260 flows back to the hydraulic oil source 210 through the return oil circuit P→J→G3→G2→T. And under the action of the first speed regulating valve 120 and the second speed regulating valve 130, the oil supply circuit speeds of the first three-position four-way solenoid valve 140 and the second three-position four-way solenoid valve 150 are basically the same, thereby ensuring that the outward unfolding movement speeds of the right fork 250 and the left fork 270 are consistent, and a simultaneous unfolding action of the left and right forks can be completed.

[0053] When the driver presses the switch for retracting the left and right forks at the same time, the action principle is similar to that of unfolding. At this time, the first three-position four-way solenoid valve 140 works in the left position, and its oil supply oil circuit is F1→F4→K→N. The rod chamber of the right fork moving cylinder 240 enters oil, driving the right fork 250 to move to the left, that is, to move in the direction of retraction inside the vehicle body, and the oil in the rodless chamber of the right fork moving cylinder 240 flows back to the hydraulic oil source 210 through the return oil circuit M→L→F3→F2→T. The second three-position four-way solenoid valve 150 works in the right position, and its oil supply oil circuit is G1→G3→J→P. The rod chamber of the left fork moving cylinder 260 enters oil, driving the left fork 270 to move to the right, that is, to move in the direction of retraction inside the vehicle body, and the oil in the rodless chamber of the left fork moving cylinder 260 flows back to the hydraulic oil source 210 through the return oil circuit Q→H→G4→G2→T. At the same time, the first speed regulating valve 120 and the second speed regulating valve 130 control the oil supply circuit to have the same speed, so as to complete the simultaneous retraction action of the right fork 250 and the left fork 270.

[0054] It can be seen from the above embodiments that the integrated valve group 100 and the hydraulic system 200 provided in this embodiment can realize the independent movement of the left and right forks controlled by a single oil source, and can achieve accurate flow and pressure output, avoid pressure loss, and be more energy-efficient. At the same time, the main hydraulic system does not need to reserve a fork movement hydraulic module, and the control is simpler. The independent single oil source device has a more flexible vehicle layout, fully utilizes the available space for independent layout, and the system design is simpler. The integrated valve can be arranged closer to the fork movement cylinder, shortening the pipeline length, and the function expansion is easier to control.

[0055] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0056] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. An integrated valve group for an electric forklift, characterized in that: It includes a main oil inlet A and a main oil outlet T and a relief valve connected between the main oil inlet A and the main oil outlet T; a first speed regulating valve, a second speed regulating valve, a first three-position four-way solenoid valve and a second three-position four-way solenoid valve are also connected between the main oil inlet A and the main oil outlet T; The inlet B end of the first speed regulating valve and the inlet C end of the second speed regulating valve are respectively connected to the main oil inlet A; The outlet of the first speed regulating valve is connected to the F1 end of the first three-position four-way solenoid valve, and the outlet of the second speed regulating valve is connected to the G1 end of the second three-position four-way solenoid valve; The F2 end of the first three-position four-way solenoid valve and the G2 end of the second three-position four-way solenoid valve are respectively connected to the main oil outlet T; The F3 end and F4 end of the first three-position four-way solenoid valve are connected to the L port and K port of the integrated valve group respectively, and the G3 end and G4 end of the second three-position four-way solenoid valve are connected to the J port and H port of the integrated valve group respectively.

2. An electric forklift hydraulic system, characterized in that: The invention comprises the integrated valve group for electric forklift according to claim 1.

3. The electric forklift hydraulic system according to claim 2, characterized in that: include: The integrated valve assembly for an electric forklift according to claim 1; A hydraulic oil source connected to a main oil outlet T of the integrated valve group for the electric forklift; A power pump group, whose inlet is connected to the hydraulic oil source, and whose outlet is connected to the main oil inlet A of the integrated valve group for the electric forklift; As well as the right fork moving cylinder and the left fork moving cylinder; Among them, the L port and K port of the integrated valve group for electric forklift are respectively connected to the rodless chamber M port and the rod chamber N port of the right fork moving cylinder, and the J port and H port of the integrated valve group for electric forklift are respectively connected to the rod chamber P port and the rodless chamber Q port of the left fork moving cylinder.

4. The electric forklift hydraulic system according to claim 3, characterized in that: The right fork moving cylinder is connected to the right fork, and the left fork moving cylinder is connected to the left fork.

5. The electric forklift hydraulic system according to claim 3, characterized in that: The power pump group includes a motor and a gear pump, and the motor is connected to the gear pump.

6. The electric forklift hydraulic system according to claim 5, characterized in that: The oil inlet of the gear pump is connected to the hydraulic oil source, and the oil outlet of the gear pump is connected to the main oil inlet A of the integrated valve group for the electric forklift.

7. The electric forklift hydraulic system according to claim 2, characterized in that: When the left position of the first three-position four-way solenoid valve is energized, the F1 end and the F4 end of the first three-position four-way solenoid valve are connected, the F3 end and the F2 end of the first three-position four-way solenoid valve are connected, the oil supply circuit is F1→F4→K→N, and the oil return circuit is M→L→F3→F2→T; When the right position of the first three-position four-way solenoid valve is energized, the F1 end and the F3 end of the first three-position four-way solenoid valve are connected, the F4 end and the F2 end of the first three-position four-way solenoid valve are connected, the oil supply circuit is F1→F3→L→M, and the oil return circuit is N→K→F4→F2→T.

8. The electric forklift hydraulic system according to claim 2, characterized in that: When the left position of the second three-position four-way solenoid valve is energized, the G1 end and the G4 end of the second three-position four-way solenoid valve are connected, the G3 end and the G2 end of the second three-position four-way solenoid valve are connected, the oil supply circuit is G1→G4→H→Q, and the oil return circuit is P→J→G3→G2→T; When the right position of the second three-position four-way solenoid valve is energized, the G1 end and G3 end of the second three-position four-way solenoid valve are connected, the G4 end and G2 end of the second three-position four-way solenoid valve are connected, the oil supply circuit is G1→G3→J→P, and the oil return circuit is Q→H→G4→G2→T.

9. An electric forklift, characterized in that: Contains an electric forklift hydraulic system as described in any one of claims 2 to 8.

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