An integrated flameout drop arm valve, hydraulic system, and apparatus

Abstract

The utility model discloses a kind of flameout falling boom integrated valve, hydraulic system and equipment, the integrated valve includes controllable bypass oil circuit and constant throttle oil circuit of on-off;The first port of bypass oil circuit is communicated with the rodless cavity of external boom cylinder, the second port of bypass oil circuit is communicated with the rod cavity of external boom cylinder, the first port of throttle oil circuit is communicated with bypass oil circuit, the second port of throttle oil circuit is communicated with external oil tank.Communication is set between the rodless cavity of boom cylinder and the rod cavity of boom cylinder in the utility model, when flameout falls boom, boom cylinder rod cavity oil is supplemented by bypass oil circuit, avoid boom cylinder rod cavity unable to supplement oil influence boom descending performance, and the utility model only needs to control bypass oil circuit on-off, without boom cylinder rodless cavity overflow valve or joint is relieved.

Description

Technical Field

[0001] This utility model relates to an integrated valve for shutting off and lowering the boom, a hydraulic system and equipment, belonging to the field of hydraulic systems for engineering machinery. Background Technology

[0002] In construction machinery such as excavators and loaders, the boom hydraulic cylinder is a key component for performing lifting operations. When the engine suddenly shuts down due to a malfunction (such as running out of fuel or electrical system failure), the working pump stops supplying oil, and the entire hydraulic system loses power. At this time, shutting down the boom is a crucial safety device. Its core purpose is to enable the boom (and its load) to be lowered to the ground in a safe and controllable manner in the above emergency situations.

[0003] There are some problems with the existing method of shutting down the boom: 1. Poor reliability: The weight of the load will cause extremely high pressure in the rodless chamber of the boom cylinder, while the rod chamber of the boom cylinder cannot be replenished with oil, affecting the boom lowering performance.

[0004] 2. Inconvenient operation and safety hazards: Operators usually need to manually loosen the overflow valve or connector of the rodless chamber of the boom cylinder to release pressure. This process is time-consuming and laborious, and the high-pressure oil spray can easily cause personal injury and environmental pollution. Utility Model Content

[0005] This utility model provides an integrated valve for shutting off and lowering the boom, a hydraulic system and equipment, which solves the problems disclosed in the background art.

[0006] According to one aspect of this application, a flameout and boom drop integrated valve is provided, including an on / off controllable bypass oil circuit and a normally open throttling oil circuit; The first port of the bypass oil circuit is connected to the rodless chamber of the external boom cylinder, the second port of the bypass oil circuit is connected to the rod chamber of the external boom cylinder, the first port of the throttling oil circuit is connected to the bypass oil circuit, and the second port of the throttling oil circuit is connected to the external oil tank. When the boom is lowered while the engine is off, the upstream section of the bypass oil circuit is open; when the boom is lowered while the engine is not off, if the pressure at the first port of the bypass oil circuit is less than the first pressure threshold, the upstream section of the bypass oil circuit is closed; if the pressure at the first port of the bypass oil circuit is greater than the first pressure threshold, the upstream section of the bypass oil circuit is open; wherein, the upstream section of the bypass oil circuit is the oil circuit between the first port of the bypass oil circuit and the connection point of the throttling oil circuit, and the downstream section of the bypass oil circuit is the oil circuit between the connection point of the throttling oil circuit and the second port of the bypass oil circuit; When the upstream section of the bypass oil circuit is open, if the pressure at the throttling oil circuit connection is less than the second pressure threshold, the downstream section of the bypass oil circuit is closed; if the pressure at the throttling oil circuit connection is greater than the second pressure threshold, the downstream section of the bypass oil circuit is open.

[0007] Furthermore, the upstream section of the bypass oil circuit includes a first directional valve, the oil inlet of which is connected to the rodless chamber of the external boom cylinder, and the oil outlet of which is connected to the first port of the throttling oil circuit and the downstream section of the bypass oil circuit.

[0008] Furthermore, the first directional valve is a first directional valve with a built-in workstation relief valve, and the first pressure threshold is the opening pressure of the workstation relief valve; when the oil inlet pressure of the first directional valve is less than the opening pressure of the workstation relief valve, the first directional valve is closed, and when the oil inlet pressure of the first directional valve is greater than the opening pressure of the workstation relief valve, the first directional valve is open.

[0009] Furthermore, the first directional valve is a manual first directional valve. When the manual first directional valve is working in the upper position, the inlet pressure of the first directional valve controls the shut-off or opening of the first directional valve. When the manual first directional valve is working in the lower position, the first directional valve is open.

[0010] Furthermore, the downstream section of the bypass oil circuit includes a check valve, the second pressure threshold is the opening pressure of the check valve, the oil inlet of the check valve is connected to the first port of the throttling oil circuit and the upstream section of the bypass oil circuit, and the oil outlet of the check valve is connected to the rod chamber of the external boom cylinder.

[0011] Furthermore, the throttling oil circuit includes a throttling valve, the inlet of which is connected to the bypass oil circuit, and the outlet of which is connected to the external oil tank.

[0012] According to another aspect of this application, a hydraulic system is provided, including the aforementioned integrated valve.

[0013] Furthermore, the system also includes a boom cylinder, a second directional valve, a working pump, and an oil tank; The inlet of the working pump is connected to the oil tank, the outlet of the working pump is connected to the inlet of the second directional valve, the two working ports of the second directional valve are respectively connected to the rodless chamber and the rod chamber of the boom cylinder, and the return port of the second directional valve is connected to the oil tank.

[0014] Furthermore, the system also includes a main relief valve, the oil inlet of which is connected to the oil outlet of the working pump and the oil tank, respectively.

[0015] According to another aspect of this application, an apparatus is provided that includes the aforementioned hydraulic system.

[0016] The beneficial effects achieved by this utility model are as follows: This utility model sets up a bypass oil circuit between the rodless chamber and the rod chamber of the boom cylinder. When the boom is lowered after the engine is turned off, the oil in the rod chamber of the boom cylinder is replenished through the bypass oil circuit, which avoids the boom lowering performance being affected by the inability to replenish the oil in the rod chamber of the boom cylinder. Furthermore, this utility model only needs to control the opening and closing of the bypass oil circuit, without the need to depressurize the overflow valve or connector of the rodless chamber of the boom cylinder. Attached Figure Description

[0017] Figure 1 A schematic diagram of the integrated valve for shutting off the boom; Figure 2 This is a schematic diagram of the hydraulic system. Detailed Implementation

[0018] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this application or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0019] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application.

[0020] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0021] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0022] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0023] It should be noted that similar symbols and letters in the following figures represent similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0024] Furthermore, in the description of the embodiments of this application, the terms "first," "second," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance. Therefore, features defined with "first" or "second" may explicitly or implicitly include one or more features.

[0025] See Figure 1 , Figure 1 This is a schematic diagram of the structure of an integrated valve for shutting off the boom provided in an embodiment of this application. The integrated valve may include at least a bypass oil circuit 1 that can be controlled to open and close and a throttling oil circuit 2 that is normally open.

[0026] The first port of the bypass oil circuit 1 is connected to the rodless chamber of the external boom cylinder 6, the second port of the bypass oil circuit 1 is connected to the rod chamber of the external boom cylinder 6, the first port of the throttling oil circuit 2 is connected to the bypass oil circuit 1, and the second port of the throttling oil circuit 2 is connected to the external oil tank 3.

[0027] When the boom is lowered while the engine is off, the upstream section of bypass oil circuit 1 is open; when the boom is lowered while the engine is not off, if the pressure at the first port of bypass oil circuit 1 is less than the first pressure threshold, the upstream section of bypass oil circuit 1 is closed; if the pressure at the first port of bypass oil circuit 1 is greater than the first pressure threshold, the upstream section of bypass oil circuit 1 is open; wherein, the upstream section of bypass oil circuit 1 is the oil circuit between the first port of bypass oil circuit 1 and the connection point of throttling oil circuit 2, and the downstream section of bypass oil circuit 1 is the oil circuit between the connection point of throttling oil circuit 2 and the second port of bypass oil circuit 1.

[0028] When the upstream section of bypass oil circuit 1 is open, if the pressure at the connection of throttling oil circuit 2 in bypass oil circuit 1 is less than the second pressure threshold, the downstream section of bypass oil circuit 1 is closed; if the pressure at the connection of throttling oil circuit 2 in bypass oil circuit 1 is greater than the second pressure threshold, the downstream section of bypass oil circuit 1 is open.

[0029] When the boom is lowered without shutting off the engine, if the pressure at the first port of the bypass oil circuit 1 is less than the first pressure threshold, the upstream section of the bypass oil circuit 1 is cut off. This means that the oil inside the rodless chamber of the boom cylinder 6 cannot enter the subsequent oil circuit, thus ensuring that the boom's settling amount is not affected. If the pressure at the first port of the bypass oil circuit 1 is greater than the first pressure threshold, the upstream section of the bypass oil circuit 1 is open. This means that the oil inside the rodless chamber of the boom cylinder 6 can enter the subsequent oil circuit (at least return to the oil tank 3), thus unloading the oil from the rodless chamber of the boom cylinder 6 and ensuring that the boom overload is not affected.

[0030] When the boom is lowered after the engine is shut off, the upstream section of the bypass oil circuit 1 is directly connected. When the output oil pressure of the upstream section of the bypass oil circuit 1 is low, the downstream section of the bypass oil circuit 1 is cut off. All the oil in the rodless chamber of the boom cylinder 6 returns to the oil tank 3 through the throttling oil circuit 2. When the output oil pressure is high, the oil in the rodless chamber of the boom cylinder 6 can replenish the oil in the rod chamber of the boom cylinder 6, thereby ensuring that the rod chamber of the boom cylinder 6 will not suck in air when the boom is lowered, and avoiding the inability of the rod chamber of the boom cylinder 6 to replenish oil, which would affect the boom lowering performance.

[0031] The aforementioned integrated valve for lowering the boom after engine shutdown only needs to control the opening and closing of the bypass oil circuit 1, without needing to depressurize the overflow valve or connector of the rodless chamber of the boom cylinder 6. This process saves time and effort and avoids high-pressure oil spraying. Furthermore, the aforementioned normally open throttling oil circuit 2 can prevent the boom from lowering too quickly when the engine is shut off, thus avoiding the problem of excessive impact during boom descent and ensuring safety and comfort.

[0032] It should be noted that all components in the aforementioned integrated valve are integrated into a single valve body, and the valve body surface has only three oil ports, such as... Figure 1 The oil ports A, B, and T are connected to the first port of the bypass oil circuit 1 and externally to the rodless chamber of the boom cylinder 6. The oil port B is connected to the second port of the bypass oil circuit 1 and externally to the rod chamber of the boom cylinder 6. The oil port T is connected to the second port of the throttling oil circuit 2 and externally to the oil tank 3.

[0033] Considering the limited assembly space of small engineering machinery, the above-mentioned integrated valve can use cartridge components, which can meet the working flow requirements while significantly reducing the component size, resulting in a high degree of integration, small space occupation, and more flexible layout.

[0034] It should be noted that, in some embodiments, the upstream section of the bypass oil circuit 1 may include a first directional valve 11. The inlet of the first directional valve 11 is connected to the rodless chamber of the external boom cylinder 6, and the outlet of the first directional valve 11 is connected to the first port of the throttling oil circuit 2 and the downstream section of the bypass oil circuit 1. The first directional valve 11 may be a first directional valve 11 with a built-in workstation relief valve, and the first pressure threshold is the opening pressure of the workstation relief valve. When the inlet pressure of the first directional valve 11 is less than the opening pressure of the workstation relief valve, the first directional valve 11 is closed; when the inlet pressure of the first directional valve 11 is greater than the opening pressure of the workstation relief valve, the first directional valve 11 is open.

[0035] To ensure the reliability of the on / off control of the first directional valve 11, the first directional valve 11 can be a manual first directional valve 11. When the manual first directional valve 11 is working in the upper position, the oil inlet pressure of the first directional valve 11 controls the shut-off or opening of the first directional valve 11. When the manual first directional valve 11 is working in the lower position, the first directional valve 11 is open.

[0036] The aforementioned first directional valve 11 can specifically be a two-position two-way manual directional valve. This type of valve is an existing valve. The upper end of the two-position two-way manual directional valve is equipped with a handle. When the handle is not under force, the two-position two-way manual directional valve operates in the upper position. When the pressure at the oil inlet is less than the opening pressure of the position relief valve, the position relief valve is closed, that is, the oil is cut off at the oil inlet. When the pressure at the oil inlet is greater than the opening pressure of the position relief valve, the position relief valve is opened, that is, the oil enters the downstream oil circuit through the two-position two-way manual directional valve. When the upper handle is under force, the two-position two-way manual directional valve operates in the lower position, and the position relief valve is directly opened.

[0037] It should be noted that, in some embodiments, the downstream section of the bypass oil circuit 1 may include a one-way valve 12, the second pressure threshold is the opening pressure of the one-way valve 12, the oil inlet of the one-way valve 12 is connected to the first port of the throttling oil circuit 2 and the upstream section of the bypass oil circuit 1 (i.e. the oil outlet of the two-position two-way manual directional valve), and the oil outlet of the one-way valve 12 is connected to the rod chamber of the external boom cylinder 6.

[0038] The check valve 12 can be a hydraulically controlled check valve, which is also an existing valve. The upper end of the hydraulically controlled check valve is equipped with a spring. When the pressure at the lower end of the hydraulically controlled check valve is less than the spring force, all the oil returns to the oil tank 3. When the pressure at the lower end of the hydraulically controlled check valve is greater than the spring force, the hydraulically controlled check valve opens, and the oil is sent through the hydraulically controlled check valve to the rod chamber of the boom cylinder 6, and then returns to the oil tank 3 through the throttle valve.

[0039] It should be noted that the throttling oil circuit 2 may include a throttling valve 21. The oil inlet of the throttling valve 21 is connected to the bypass oil circuit 1, that is, connected to the oil inlet of the hydraulic control check valve and the oil outlet of the two-position two-way manual directional valve. The oil outlet of the throttling valve 21 is connected to the external oil tank 3. By throttling the oil through the throttling valve 21, the problem of the boom descending too quickly when the engine is turned off and the boom is lowered, which would cause a large impact when the boom descends, can be avoided, thus ensuring safety and comfort.

[0040] See Figure 2 , Figure 2 This is a schematic diagram of a hydraulic system provided in an embodiment of this application. The system may include at least the aforementioned integrated valve, which enables the boom to be lowered safely and quickly in a controllable manner after the engine is shut down.

[0041] Figure 2 The system specifically includes a boom cylinder 6, a second directional valve 5, a working pump 4, and an oil tank 3. The oil inlet of the working pump 4 is connected to the oil tank 3, the oil outlet of the working pump 4 is connected to the oil inlet of the second directional valve 5 (i.e., port p in the figure), the two working ports of the second directional valve 5 (i.e., ports a and b in the figure) are respectively connected to the rodless chamber and the rod chamber of the boom cylinder 6, and the oil return port of the second directional valve 5 (i.e., port t in the figure) is connected to the oil tank 3.

[0042] In order to ensure the safety of the oil circuit, a main relief valve 7 is also installed in the system. The oil inlet and outlet of the main relief valve 7 are connected to the oil outlet of the working pump 4 and the oil tank 3, respectively.

[0043] When the construction machinery equipped with the above system is in operation, the piston rod of the boom cylinder 6 can be extended and retracted by operating the second reversing valve 5 to switch left and right, thereby controlling the lifting and lowering of the working device of the construction machinery.

[0044] This application also discloses a device that may include at least the aforementioned hydraulic system. This device may be an excavator, loader, or other construction machinery. Without changing the original control method of the engine shutdown boom lowering valve, this device adopts mechanical control, which can make the boom lowering smooth and gentle in the case of unexpected engine shutdown. Compared with the prior art, the boom lowering performance will no longer be affected by insufficient oil in the boom cylinder 6 rod, which can greatly improve safety performance.

[0045] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.

Claims

1. An integrated valve for shutting off and lowering the boom, characterized in that, This includes bypass oil circuits with controllable on / off states and throttling oil circuits that are always open; The first port of the bypass oil circuit is connected to the rodless chamber of the external boom cylinder, the second port of the bypass oil circuit is connected to the rod chamber of the external boom cylinder, the first port of the throttling oil circuit is connected to the bypass oil circuit, and the second port of the throttling oil circuit is connected to the external oil tank. When the boom is lowered while the engine is off, the upstream section of the bypass oil circuit is open; when the boom is lowered while the engine is not off, if the pressure at the first port of the bypass oil circuit is less than the first pressure threshold, the upstream section of the bypass oil circuit is closed; if the pressure at the first port of the bypass oil circuit is greater than the first pressure threshold, the upstream section of the bypass oil circuit is open; wherein, the upstream section of the bypass oil circuit is the oil circuit between the first port of the bypass oil circuit and the connection point of the throttling oil circuit, and the downstream section of the bypass oil circuit is the oil circuit between the connection point of the throttling oil circuit and the second port of the bypass oil circuit; When the upstream section of the bypass oil circuit is open, if the pressure at the throttling oil circuit connection is less than the second pressure threshold, the downstream section of the bypass oil circuit is closed; if the pressure at the throttling oil circuit connection is greater than the second pressure threshold, the downstream section of the bypass oil circuit is open.

2. The integrated valve according to claim 1, characterized in that, The upstream section of the bypass oil circuit includes a first directional valve, the oil inlet of which is connected to the rodless chamber of the external boom cylinder, and the oil outlet of which is connected to the first port of the throttling oil circuit and the downstream section of the bypass oil circuit.

3. The integrated valve according to claim 2, characterized in that, The first directional valve is a first directional valve with a built-in workstation relief valve. The first pressure threshold is the opening pressure of the workstation relief valve. When the oil inlet pressure of the first directional valve is less than the opening pressure of the workstation relief valve, the first directional valve is closed. When the oil inlet pressure of the first directional valve is greater than the opening pressure of the workstation relief valve, the first directional valve is open.

4. The integrated valve according to claim 3, characterized in that, The first directional valve is a manual first directional valve. When the manual first directional valve is working in the upper position, the oil inlet pressure of the first directional valve controls the shut-off or opening of the first directional valve. When the manual first directional valve is working in the lower position, the first directional valve is open.

5. The integrated valve according to claim 1, characterized in that, The downstream section of the bypass oil circuit includes a check valve. The second pressure threshold is the opening pressure of the check valve. The oil inlet of the check valve is connected to the first port of the throttling oil circuit and the upstream section of the bypass oil circuit. The oil outlet of the check valve is connected to the rod chamber of the external boom cylinder.

6. The integrated valve according to claim 1, 2, or 5, characterized in that, The throttling oil circuit includes a throttling valve, the inlet of which is connected to the bypass oil circuit, and the outlet of which is connected to the external oil tank.

7. A hydraulic system, characterized in that, Includes the integrated valve as described in any one of claims 1 to 6.

8. The system according to claim 7, characterized in that, The system also includes a boom cylinder, a second directional valve, a working pump, and an oil tank; The inlet of the working pump is connected to the oil tank, the outlet of the working pump is connected to the inlet of the second directional valve, the two working ports of the second directional valve are respectively connected to the rodless chamber and the rod chamber of the boom cylinder, and the return port of the second directional valve is connected to the oil tank.

9. The system according to claim 8, characterized in that, The system also includes a main relief valve, the oil inlet of which is connected to the oil outlet of the working pump and the oil tank, respectively.

10. A device, characterized in that, Includes the system described in any one of claims 7 to 9.

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