A loader control method to save energy and reduce consumption by reducing overflow pressure

Abstract

This invention discloses a loader control method for energy saving and consumption reduction by lowering overflow pressure, belonging to the field of loader hydraulic control technology. A port overflow valve is provided on each of the two passages connecting the flow control valve to the two chambers on both sides of the hydraulic cylinder. A main overflow valve is connected to the passage between the two port overflow valves and the two chambers on both sides of the hydraulic cylinder. The set pressure of the main overflow valve is controlled to be lower than the set pressure of the port overflow valves. When the system working pressure is low, pressure is released through the port overflow valves; when the system working pressure is high, pressure is released through the port overflow valves. By releasing pressure in the hydraulic system through the main overflow valve with a lower set pressure, losses can be reduced at low system working pressures. Furthermore, the presence of two port overflow valves ensures effective pressure release under high pressures, thereby guaranteeing normal operation of the system under both low and high working pressures. Compared to existing hydraulic systems, this method achieves energy saving and consumption reduction.

Description

Technical Field

[0001] This invention belongs to the field of hydraulic control technology for loaders, specifically a loader control method that reduces energy consumption and emissions by lowering overflow pressure. Background Technology

[0002] In existing hydraulic loaders with fixed displacement pumps, the main pump outputs a fixed flow rate. When the system requires a smaller flow rate, excess hydraulic oil is discharged through the main relief valve. Since the relief valve's setpoint is fixed, this results in higher system pressure during relief. Since system power equals pressure multiplied by flow rate, this leads to higher system energy consumption.

[0003] The loader's hydraulic system's main relief valve uses a spring and the system's maximum working pressure to jointly control the relief pressure. The main relief valve's relief pressure equals the set pressure plus the maximum working pressure, where the set pressure is a smaller, fixed value. When the hydraulic system's maximum working pressure is low, the main relief valve's set pressure is also low, allowing for a smaller relief pressure, thus achieving energy savings and reduced consumption. Conversely, when the system's working pressure is high, the relief pressure also increases. The system's maximum pressure is set using a port relief valve to meet the system's operational requirements. Summary of the Invention

[0004] 1. The technical problem that the invention aims to solve

[0005] The purpose of this invention is to solve the problem of high system energy consumption when reducing overflow pressure in existing hydraulic loaders.

[0006] 2. Technical Solution

[0007] To achieve the above objectives, the technical solution provided by the present invention is as follows:

[0008] The present invention discloses a loader control method for saving energy and reducing consumption by reducing overflow pressure. A port overflow valve is provided on each of the two passages connecting the flow control valve to the two chambers on both sides of the hydraulic cylinder. A main overflow valve is connected between the two port overflow valves and the passages between the two chambers on both sides of the hydraulic cylinder. The set pressure of the main overflow valve is controlled to be lower than the set pressure of the port overflow valves. When the system working pressure is low, pressure is released through the port overflow valves; when the system working pressure is high, pressure is released through the port overflow valves.

[0009] Preferably, the ratio of the set pressure of the main relief valve to the set pressure of the port relief valve is 1:8 to 1:10.

[0010] Preferably, the method is performed using the following system:

[0011] It includes a pilot control line and a flow control valve connected to the pilot control line. The flow control valve is connected to a hydraulic cylinder. The two chambers of the hydraulic cylinder are respectively connected to different output ends of the flow control valve, and both sides of the passage are provided with port relief valves. The two sides of the passage form a passage directly between the port relief valve and the hydraulic cylinder and are connected to a main relief valve. The set pressure of the main relief valve is less than the set pressure of the port relief valve.

[0012] Preferably, the outlet of the hydraulic oil tank is connected to the inlet of a fixed displacement pump, and the outlet of the fixed displacement pump is connected to a flow control valve.

[0013] Preferably, the metering pump is connected to a power unit.

[0014] Preferably, the main relief valve and the flow control valve are directly connected by a check valve, and the direction of restriction of the check valve is from the main relief valve to the flow control valve.

[0015] Preferably, the inlets of the two side passages connected to the main relief valve are equipped with check valves, and both the port relief valve and the main relief valve are connected to the hydraulic oil tank.

[0016] 3. Beneficial effects

[0017] Compared with the prior art, the technical solution provided by this invention has the following advantages:

[0018] This invention discloses a loader control method for energy saving and consumption reduction by lowering overflow pressure. A port overflow valve is installed on each of the two passages connecting the flow control valve to the two chambers on both sides of the hydraulic cylinder. A main overflow valve is connected between the two port overflow valves and the passages between the two chambers on both sides of the hydraulic cylinder. The set pressure of the main overflow valve is controlled to be lower than the set pressure of the port overflow valves. When the system operating pressure is low, pressure is released through the port overflow valves; when the system operating pressure is high, pressure is released through the port overflow valves. By releasing pressure in the hydraulic system through the main overflow valve with a lower set pressure, losses can be reduced at low system operating pressures. Furthermore, the presence of two port overflow valves ensures effective pressure release under high pressures, thereby guaranteeing normal operation of the system under both low and high operating pressures. Compared to existing hydraulic systems, this method achieves energy saving and consumption reduction. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of a loader control method for saving energy and reducing consumption by reducing overflow pressure, according to the present invention.

[0020] Explanation of the labels in the diagram:

[0021] 1. Pilot control pipeline; 2. Flow control valve; 3. Port relief valve; 4. Check valve; 5. Working cylinder; 6. Main relief valve; 7. Power unit; 8. Fixed displacement pump; 9. Hydraulic oil tank. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0023] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0024] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0025] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0026] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linking," and "socketing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; 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, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0027] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0028] Example 1

[0029] See attached document Figure 1 This embodiment presents a loader control method that reduces energy consumption and emissions by lowering overflow pressure. Two overflow valves 3 are respectively installed on the two passages connecting the flow control valve 2 to the two chambers on both sides of the hydraulic cylinder 5. A main overflow valve 6 is connected between the two overflow valves 3 and the passages between the two chambers on both sides of the hydraulic cylinder 5. The set pressure of the main overflow valve 6 is controlled to be lower than the set pressure of the overflow valves 3. When the system working pressure is low, pressure is released through the overflow valves 3; when the system working pressure is high, pressure is released through the overflow valves 3. This method uses the main overflow valve 6 with a lower set pressure to release pressure in the hydraulic system, reducing losses at low system working pressures. The two overflow valves 3 ensure effective pressure release under high pressures, thus guaranteeing normal operation of the system under both low and high working pressures. Compared to existing hydraulic systems, this method achieves energy conservation and emission reduction.

[0030] The ratio of the set pressure of the main relief valve 6 to the set pressure of the port relief valve 3 is 1:8 to 1:10. If the set pressure is too high, it will cause a large overflow loss. If it is too low, it will cause too much pressure oil output by the pump to flow out from the main relief valve, resulting in insufficient oil supply to the system.

[0031] The system includes a pilot control line 1 and a flow control valve 2 connected to the pilot control line 1. The flow control valve 2 is connected to a hydraulic cylinder 5. The two chambers of the hydraulic cylinder 5 are respectively connected to different output ends of the flow control valve 2, and both sides of the cylinder are equipped with port relief valves 3. The two side passages form a direct connection between the port relief valves 3 and the hydraulic cylinder 5, and are connected to a main relief valve 6. The set pressure of the main relief valve 6 is lower than the set pressure of the port relief valves 3. The outlet of the hydraulic oil tank 9 is connected to the inlet of a fixed displacement pump 8, and the outlet of the fixed displacement pump 8 is connected to the flow control valve 2. The fixed displacement pump 8 is connected to a power unit 7. The power unit 7 provides power to the fixed displacement pump 8, thereby pumping hydraulic oil from the hydraulic oil tank 9 into the system to ensure normal system operation.

[0032] The main relief valve 6 is directly connected to the flow control valve 2 by a check valve 4. The direction of the check valve 4 is limited from the main relief valve 6 to the flow control valve 2. The inlets of the two passages connected to the main relief valve 6 are each equipped with a check valve 4. Both the port relief valve 3 and the main relief valve 6 are connected to the hydraulic oil tank 9.

[0033] The above-described embodiments are merely illustrative of certain implementations of the present invention, and are described in a relatively specific and detailed manner. However, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements are all within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A loader control method for energy saving and consumption reduction by reducing the flow overpressure, characterized by: Two port relief valves (3) are respectively arranged on two passages connecting the two side cavities of the hydraulic cylinder (5) with the flow control valve (2), the passages between the two port relief valves (3) and the two side cavities of the hydraulic cylinder (5) are connected with a main relief valve (6), the set pressure of the main relief valve (6) is less than the set pressure of the port relief valve (3), when the system working pressure is low, pressure relief is carried out through the main relief valve (6), when the system working pressure is high, pressure relief is carried out through the port relief valve (3); the ratio of the set pressure of the main relief valve (6) to the set pressure of the port relief valve (3) is 1:8~1:10; the method uses the following system: The method comprises a pilot control pipeline (1) and a flow control valve (2) in communication with the pilot control pipeline (1), the flow control valve (2) is connected with a hydraulic cylinder (5), the two side cavities of the hydraulic cylinder (5) are respectively connected with different output ends of the flow control valve (2) and are respectively provided with port relief valves (3), the two side passages are directly connected with the hydraulic cylinder (5) at the port relief valves (3) and are connected with a main relief valve (6).

2. The control method for a loader to save energy and reduce consumption by reducing the flow pressure according to claim 1, characterized in that: The inlets of the two side passages connected with the main relief valve (6) are respectively provided with one-way valves (4), the port relief valves (3) and the main relief valve (6) are connected with a hydraulic oil tank (9), the outlet of the hydraulic oil tank (9) is connected with the inlet of a constant pump (8), the outlet of the constant pump (8) is connected with the flow control valve (2).

3. The control method for a loader to save energy and reduce consumption by reducing the flow pressure according to claim 2, characterized in that: The constant pump (8) is connected with a power device (7).

4. The control method for a loader to save energy and reduce consumption by reducing the flow pressure according to claim 1, characterized in that: The main relief valve (6) is directly connected with a one-way valve (4) of the flow control valve (2), the one-way valve (4) is limited in the direction from the main relief valve (6) to the flow control valve (2).

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