A valve behind compensation multi-way valve load pressure feedback system

Abstract

A multi-way valve load pressure feedback system with post-valve compensation includes a main directional valve connected to pressure oil, an oil tank, an actuator, and a compensation valve. The compensation valve has an inlet and an outlet connected to opposite sides of the main directional valve. Pressure oil passes through the main directional valve and then into the compensation valve, subsequently supplying the actuator via the main directional valve. An unloading valve is connected to the other outlet of the compensation valve. The unloading valve's inlet is connected to a pressure oil source, and its outlet is connected to the oil tank. The other outlet of the compensation valve is connected to a spring end of the unloading valve, which is connected to the oil tank via a throttling device. The compensation valve core of this invention incorporates a check valve, which rapidly transmits the working port load pressure to the load feedback oil circuit, improving the hydraulic valve's response performance. Furthermore, the bypass return oil circuit required for the load feedback loop is integrated into the unloading valve stem, simplifying the internal oil circuit structure of the hydraulic valve, reducing production costs, and improving production efficiency.

Description

Technical Field

[0001] This utility model relates to the field of engineering machinery technology, specifically a post-valve compensation multi-way valve load pressure feedback system. Background Technology

[0002] In practical hydraulic systems, most loads are not constant, and situations often require multiple actuators to operate simultaneously, coordinate precisely, and without interference. Examples include multiple cylinders lifting or extending simultaneously, or multiple hydraulic motors driving in parallel, requiring synchronized start / stop. In these scenarios, traditional systems are prone to uneven flow distribution, with high-load actuators "stealing oil" and low-load actuators "stalling," resulting in asynchronous actions and unstable control. The post-valve compensated load-sensitive multi-way valve automatically adjusts the system pressure (i.e., "maximum load + ΔP") based on the load pressure, while simultaneously using a compensator (compensating valve core) to maintain a constant pressure difference in each branch, thus ensuring that the flow rate of the actuators is proportional to the control signal. Currently, post-valve compensated load-sensitive valves are widely used in hydraulic systems requiring "multi-action coordinated control, high-precision synchronization, and strong anti-interference capabilities," and are one of the core technologies of modern hydraulic control. Based on the working principle, it can be analyzed that the ability of the compensating valve core to transmit load pressure and the ability of the load feedback loop to maintain stability directly determine the overall performance level of the valve. Summary of the Invention

[0003] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a post-valve compensation multi-way valve load pressure feedback system.

[0004] This utility model is achieved through the following technical solution: a multi-way valve load pressure feedback system with post-valve compensation, including a main directional valve. One side of the main directional valve is connected to pressure oil and an oil tank, and the other side of the main directional valve is connected to an actuator. The main directional valve is also connected to a compensation valve. The compensation valve has two oil outlets, which are connected to each other through a check valve assembly. The inlet and outlet of the compensation valve are respectively connected to the two sides of the main directional valve. The pressure oil enters the compensation valve after passing through the main directional valve, and then is supplied to the actuator through the main directional valve. The other oil outlet of the compensation valve is connected to an unloading valve. The inlet of the unloading valve is connected to a pressure oil source, and the outlet of the unloading valve is connected to an oil tank. The other oil outlet of the compensation valve is connected to a spring end of the unloading valve, and the spring end is connected to the oil tank through a throttling device.

[0005] Furthermore, the main directional valve is a three-position seven-way solenoid directional valve.

[0006] The compensation valve is a three-position three-way hydraulic directional valve.

[0007] The compensation valve includes a compensation valve core, a one-way valve assembly, a spring, and a compensation valve plug. The compensation valve plug encloses the compensation valve core and the spring in the valve body. The one-way valve assembly is disposed inside the compensation valve core. The two oil outlets of the compensation valve core are the working oil circuit and the load pressure feedback oil circuit, respectively. When the one-way valve assembly is opened, the working oil circuit and the load pressure feedback oil circuit are connected inside the compensation valve.

[0008] The one-way valve assembly includes a one-way valve plug, a one-way valve spring, and a steel ball, wherein the movement direction of the steel ball is consistent with the movement direction of the compensating valve core.

[0009] The unloading valve is a two-position, two-way hydraulically controlled directional valve.

[0010] The unloading valve includes an unloading valve stem, a throttling plug I, a screw plug, a valve body, and a spring. The screw plug encloses the unloading valve stem and spring within the valve body. The unloading valve stem has a hollow structure. A throttling plug I is provided at the end of the unloading valve stem near the spring. The valve body has an oil port connecting a pressure oil source, an oil tank, and a load pressure feedback oil circuit. The hollow structure of the unloading valve stem is connected to the oil port of the oil tank. The pressure oil from the load pressure feedback oil circuit is connected to the oil tank through the throttling plug I and the hollow structure of the unloading valve stem.

[0011] An overflow valve and a throttling plug are sequentially provided between the compensation valve and the unloading valve.

[0012] This utility model has the following advantages: The post-valve compensation multi-way valve load pressure feedback system of this utility model has a one-way valve inside the compensation valve core, which can quickly transmit the load pressure of the working port to the load feedback oil circuit, thereby improving the response performance of the hydraulic valve; in addition, the bypass return oil circuit required by the load feedback circuit is integrated into the unloading valve stem, which simplifies the internal oil circuit structure of the hydraulic valve, reduces production costs, and improves production efficiency while filtering out pressure fluctuations in the load feedback oil circuit. Attached Figure Description

[0013] The accompanying drawings, as part of this utility model, are used to provide a further understanding of the present utility model. The illustrative embodiments and descriptions of the present utility model are used to explain the present utility model, but do not constitute an undue limitation of the present utility model. Obviously, the drawings described below are merely some embodiments; those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0014] In the attached diagram:

[0015] Figure 1 This is a hydraulic schematic diagram of this utility model;

[0016] Figure 2 This is a schematic diagram of the unloading valve of this utility model;

[0017] Figure 3 This is a schematic diagram of the compensating valve of this utility model.

[0018] In the diagram: 1. Unloading valve, 2. Main directional valve, 3. Compensating valve, 4. Throttling plug II, 5. Overflow valve, 1-1. Unloading valve stem, 1-2. Throttling plug I, 1-3. Screw plug, 1-4. Valve body, 3-1. Compensating valve core, 3-2. Check valve plug, 3-3. Check valve spring, 3-4. Steel ball, 3-5. Spring, 3-6. Compensating valve screw plug.

[0019] It should be noted that these accompanying drawings and textual descriptions are not intended to limit the scope of the present invention in any way, but rather to illustrate the concept of the present invention to those skilled in the art by referring to specific embodiments. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate this utility model, but are not intended to limit the scope of this utility model.

[0021] In the description of this utility model, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] like Figures 1 to 3The illustrated multi-way valve load pressure feedback system includes a main directional valve 2. One side of the main directional valve 2 is connected to pressure oil and an oil tank, and the other side is connected to an actuator. The main directional valve 2 is also connected to a compensation valve 3. The compensation valve 3 has two oil outlets connected to each other via a check valve assembly. The inlet and outlet of the compensation valve 3 are respectively connected to the two sides of the main directional valve 2. The pressure oil enters the compensation valve 3 after passing through the main directional valve 2, and then is supplied to the actuator via the main directional valve 2. The other oil outlet of the compensation valve 3 is connected to an unloading valve 1. The inlet of the unloading valve 1 is connected to a pressure oil source, and the outlet of the unloading valve 1 is connected to an oil tank. The other oil outlet of the compensation valve 3 is connected to a spring end of the unloading valve 1, and the spring end is connected to the oil tank via a throttling device. In the post-valve compensation multi-way valve load pressure feedback system of this utility model, the main directional valve connects the pressure oil source and the actuator, and is also connected to a compensation valve. The pressure oil source entering the main directional valve does not directly supply the actuator, but is distributed to the actuator by the main directional valve after passing through the compensation valve. The compensation valve has two oil outlets, which are connected internally by a check valve assembly. One oil outlet is connected to the main directional valve to supply pressure oil to the actuator, and the other oil outlet is connected to an unloading valve. This unloading valve is connected to a control terminal, which is a spring end. The spring end is internally connected to the oil tank through a throttling device. When hydraulic oil flows into the spring end, it can bypass the return oil through the throttling device to eliminate pressure fluctuations. At the same time, after the pressure in the spring chamber is established, the unloading valve can remain in a non-switching state, allowing high pressure to be established at port P, and the system to operate normally. Furthermore, this system can be equipped with multiple main directional valves, each connected to a compensating valve. The outlets of all compensating valves are connected to a common unloading valve. Load pressure is fed back through the compensating valves of each main directional valve, and the unloading valve regulates the system pressure. This not only improves the response performance of the hydraulic valves but also simplifies the internal oil circuit structure, reduces production costs, and increases production efficiency. When the system flow is insufficient, the flow rate at each working port can be proportionally distributed.

[0024] like Figure 1 The diagram illustrates a post-valve compensation multi-way valve load pressure feedback system, wherein the main directional valve 2 is a three-position seven-way solenoid directional valve. The main directional valve of this invention has seven ports and three status positions. Of the seven ports, one is connected to pressurized oil, one to the oil tank, one to the outlet of the compensation valve, two to the actuator, and two in parallel to the inlet of the compensation valve. Of the three status positions, there are two operating positions and one stop position.

[0025] like Figure 1 and Figure 3The diagram illustrates a post-valve compensation multi-way valve load pressure feedback system, wherein the compensation valve 3 is a three-position three-way hydraulic directional valve. The compensation valve of this invention has three ports and three status positions. Of the three ports, one is an inlet and two are outlets. The three status positions represent different opening degrees of the compensation valve, thus regulating the flow rate.

[0026] like Figure 1 and Figure 3 The diagram illustrates a multi-way valve load pressure feedback system with post-valve compensation. The compensation valve 3 includes a compensation valve core 3-1, a one-way valve assembly, a spring 3-5, and a compensation valve plug 3-6. The compensation valve plug 3-6 encloses the compensation valve core 3-1 and the spring 3-5 within the valve body. The one-way valve assembly is disposed within the compensation valve core 3-1. The two oil outlets of the compensation valve core 3-1 are the working oil circuit and the load pressure feedback oil circuit, respectively. When the one-way valve assembly is opened, the working oil circuit and the load pressure feedback oil circuit are connected within the compensation valve 3. This invention's compensation valve incorporates the valve core, spring, and plug found in conventional valve structures, and also includes a one-way valve assembly. The one-way valve assembly, disposed within the compensation valve core, connects the two oil outlets of the compensation valve, namely the working oil circuit and the load pressure feedback oil circuit. Through the one-way valve assembly, the pressure status of the working oil circuit can be promptly fed back to the load pressure feedback oil circuit, which in turn connects to an unloading valve for adjusting the system pressure.

[0027] like Figure 3 The diagram illustrates a multi-way valve load pressure feedback system with post-valve compensation. The check valve assembly includes a check valve plug 3-2, a check valve spring 3-3, and a steel ball 3-4. The movement direction of the steel ball 3-4 is consistent with the movement direction of the compensation valve core 3-1. In this utility model, the installation orientation of each component is consistent with the overall installation orientation of the compensation valve, achieving the effect that the movement direction of the steel ball is consistent with the movement direction of the compensation valve core. This allows the hydraulic oil at the inlet end of the compensation valve to enter the working oil circuit, driving the check valve assembly to connect with the load pressure feedback oil circuit, thus effectively and promptly transmitting the working oil circuit pressure.

[0028] like Figure 1 and Figure 2 The diagram illustrates a multi-way valve load pressure feedback system with post-valve compensation. The unloading valve 1 is a two-position, two-way hydraulic directional valve. The unloading valve of this invention has two ports and two status positions. One port is connected to a pressure oil source, and the other is connected to an oil tank. One status position is the shut-off position, and the other is the connected position.

[0029] like Figure 2The diagram illustrates a multi-way valve load pressure feedback system with post-valve compensation. The unloading valve 1 includes an unloading valve stem 1-1, a throttling plug I 1-2, a screw plug 1-3, a valve body 1-4, and a spring. The screw plug 1-3 encloses the unloading valve stem 1-1 and the spring within the valve body 1-4. The unloading valve stem 1-1 has a hollow structure. A throttling plug I 1-2 is installed at the end of the unloading valve stem 1-1 near the spring. The valve body 1-4 has an oil port connecting a pressure oil source, an oil tank, and a load pressure feedback oil circuit. The hollow structure of the unloading valve stem 1-1 is connected to the oil port of the oil tank. The pressure oil in the load pressure feedback oil circuit is connected to the oil tank via the throttling plug I 1-2 and the hollow structure of the unloading valve stem 1-1. The unloading valve of this invention has a hollow valve stem with a through hole at the oil tank opening, allowing the hollow structure to connect to the oil tank. This hollow structure also connects the load pressure feedback oil circuit to the oil tank. A throttling plug is located at the front end of the hollow structure; when hydraulic oil flows into the spring end, it can bypass the return oil through the throttling device to eliminate pressure fluctuations. Simultaneously, after pressure is built up in the spring chamber, the unloading valve remains in a non-reversing state, allowing high pressure to be established at port P, ensuring normal system operation.

[0030] like Figure 1 The diagram illustrates a multi-way valve load pressure feedback system with post-valve compensation. An overflow valve 5 and a throttling plug II 4 are sequentially arranged between the compensation valve 3 and the unloading valve 1. This invention, by placing an overflow valve and a throttling plug II between the oil outlet end of the compensation valve and the spring end of the unloading valve, can initially reduce system pressure fluctuations and improve the stability of system operation.

[0031] The principle of the post-valve compensation multi-way valve load pressure feedback system of this utility model is as follows:

[0032] like Figure 1 As shown, when the system is not working, the main directional valve is in the neutral position, and the high-pressure oil of the system enters the valve through the inlet P. Since the unloading valve is connected to the return oil tank through the throttle plug I, there is no pressure in the spring chamber of the unloading valve at this time. When the system pressure is greater than the set pressure of the unloading valve, the oil pushes the unloading valve rod to switch, and the oil flows through the unloading valve to the return oil port T. The whole system maintains a low pressure to avoid resource waste.

[0033] When the system is in operation, the main directional valve is in the working position. The high-pressure oil output by the main directional valve can drive the compensating valve to move. At the same time, high pressure (load pressure) is established at the working port. The load pressure at the working port can be quickly transmitted to the load pressure feedback loop through the check valve assembly in the compensating valve core, without waiting for the compensating valve to switch. After the pressure fluctuation is initially filtered out by throttle plug II, the oil in the load feedback circuit is transmitted to the unloading valve spring chamber. After the pressure fluctuation is filtered out a second time by throttle plug I, it flows to the return oil tank circuit. Because the throttle opening of throttle plug I is small, a large pressure difference will be generated when the oil in the load feedback circuit flows through throttle plug I. Therefore, high pressure can be established in the spring chamber to ensure that the unloading valve is in the initial position. The high-pressure oil in the system cannot flow from the inlet P to the return port T through the unloading valve, and the system eventually operates normally.

[0034] This utility model discloses a multi-way valve load pressure feedback system with post-valve compensation. Inside the compensation valve core, there is a one-way valve structure. The two sides of the one-way valve are connected to the working oil circuit and the feedback oil circuit, respectively. When pressure is generated in the working oil circuit after the hydraulic valve reverses, the pressure can be quickly transmitted to the feedback oil circuit through the one-way valve. Inside the unloading valve core, there is a throttling plug, connected to the feedback oil circuit and the return oil tank oil circuit, respectively. When pressure fluctuations occur in the feedback oil circuit, the throttling plug in the unloading valve core can filter the pressure, reducing system pressure fluctuations and effectively mitigating the vibration of the actuator. The system of this application can quickly feed the load pressure back to the feedback oil circuit (Ls oil circuit) and effectively alleviate the actuator vibration problem caused by pressure fluctuations in the feedback oil circuit.

[0035] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the present invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0036] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features found in other embodiments but not others, combinations of features from different embodiments are also within the scope of protection of this invention and form different embodiments. For example, in the embodiments described above, those skilled in the art can use them in combination based on known technical solutions and the technical problems to be solved by this application.

[0037] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-described technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A post-valve compensation multi-way valve load pressure feedback system, characterized in that: The system includes a main directional valve (2), one side of which is connected to pressure oil and an oil tank, and the other side of which is connected to an actuator. The main directional valve (2) is also connected to a compensation valve (3), which has two outlets connected to each other via a check valve assembly. The inlet and outlet of the compensation valve (3) are connected to the two sides of the main directional valve (2), respectively. The pressure oil enters the compensation valve (3) after passing through the main directional valve (2), and is supplied to the actuator via the main directional valve (2) after passing through the compensation valve (3). The other outlet of the compensation valve (3) is connected to an unloading valve (1), the inlet of which is connected to a pressure oil source, and the outlet of which is connected to an oil tank. The other outlet of the compensation valve (3) is connected to the spring end of the unloading valve (1), and the spring end is connected to the oil tank via a throttling device.

2. The multi-way valve load pressure feedback system with post-valve compensation as described in claim 1, characterized in that: The main directional valve (2) is a three-position seven-way solenoid directional valve.

3. The multi-way valve load pressure feedback system with post-valve compensation as described in claim 1, characterized in that: The compensation valve (3) is a three-position three-way hydraulic control directional valve.

4. The multi-way valve load pressure feedback system with post-valve compensation as described in claim 1, characterized in that: The compensation valve (3) includes a compensation valve core (3-1), a one-way valve assembly, a spring (3-5), and a compensation valve plug (3-6). The compensation valve plug (3-6) encloses the compensation valve core (3-1) and the spring (3-5) in the valve body. The one-way valve assembly is located inside the compensation valve core (3-1). The two oil outlets of the compensation valve core (3-1) are the working oil circuit and the load pressure feedback oil circuit, respectively. After the one-way valve assembly is opened, the working oil circuit and the load pressure feedback oil circuit are connected inside the compensation valve (3).

5. The multi-way valve load pressure feedback system with post-valve compensation as described in claim 4, characterized in that: The one-way valve assembly includes a one-way valve plug (3-2), a one-way valve spring (3-3), and a steel ball (3-4). The movement direction of the steel ball (3-4) is consistent with the movement direction of the compensating valve core (3-1).

6. The multi-way valve load pressure feedback system with post-valve compensation as described in claim 1, characterized in that: The unloading valve (1) is a two-position two-way hydraulic control directional valve.

7. The multi-way valve load pressure feedback system with post-valve compensation as described in claim 1, characterized in that: The unloading valve (1) includes an unloading valve stem (1-1), a throttling plug I (1-2), a screw plug (1-3), a valve body (1-4), and a spring. The screw plug (1-3) encloses the unloading valve stem (1-1) and the spring inside the valve body (1-4). The unloading valve stem (1-1) has a hollow structure. A throttling plug I (1-2) is provided at the end of the unloading valve stem (1-1) near the spring. The valve body (1-4) has an oil port that connects the pressure oil source, the oil tank, and the load pressure feedback oil circuit. The hollow structure of the unloading valve stem (1-1) is connected to the oil port of the oil tank. The pressure oil of the load pressure feedback oil circuit is connected to the oil tank through the throttling plug I (1-2) and the hollow structure of the unloading valve stem (1-1).

8. The multi-way valve load pressure feedback system with post-valve compensation as described in claim 1, characterized in that: An overflow valve (5) and a throttling plug II (4) are sequentially provided between the compensation valve (3) and the unloading valve (1).

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