Series three-position four-way hydraulic reversing circuit with compound action protection

Abstract

The present invention relates to a series-type three-position, four-way hydraulic reversing circuit with compound action protection, comprising a plurality of three-position, four-way reversing valves, a relief valve, a plurality of one-way valves, an oil inlet line, an oil return line, a main oil supply line, a main oil return line, and a plurality of oil ports; a plurality of three-position, four-way reversing valve spools are connected in series through the cooperation of the oil inlet line and the oil return line, and then their two ends are respectively connected to the main oil supply line and the main oil return line to form a circuit, and a one-way valve is installed between the oil inlet side line and the main oil supply line of each three-position, four-way reversing valve, and a relief valve is connected between the main oil supply line and the main oil return line. The main oil circuit of this application and method has no unloading valve, and the spools of each three-position, four-way valve are connected in series with the oil inlet and return lines. To achieve a control action, only a single control of each valve spool is required. At the same time, the configuration of protection elements in each reversing valve can achieve compound action protection, avoiding the danger of overpressure of the actuator caused by erroneous compound operation.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic reversing valves, and in particular relates to a series-type three-position four-way hydraulic reversing circuit with compound action protection. Background Art

[0002] A multi-valve hydraulic reversing circuit is a control valve block that controls multiple hydraulic actions through physical superposition or logical combination. Its physical structure varies, including disc-type, stacked, and cartridge-type designs. Its compact structure, standardized specifications, and strong scalability make it widely used in industrial and engineering hydraulic transmission control. Currently, the most commonly used multi-valve hydraulic reversing circuit on the market is the parallel type.

[0003] The principle of the parallel three-position four-way hydraulic reversing circuit is as follows Figure 1 As shown in the figure, this valve group consists of a three-position, four-way directional valve 1, an unloading valve 2, a relief valve 3, an oil inlet line 4, an oil return line 5, and various oil ports. Its control principle is as follows: when the hydraulic system is not in operation, unloading valve 2 is in the open state, and the oil source is unloaded. When a working link requires operation, unloading valve 2 is switched to the closed state, and three-position, four-way directional valve 1 is switched to the working position through electrical or manual control, thus achieving motion control.

[0004] Current problems: When using a manually controlled, three-position, four-way hydraulic reversing circuit, achieving a single control action requires simultaneous manual control of both the three-position, four-way directional valve and the unloading valve. This operation is complex, ergonomic, and has led to numerous user complaints. When using an electrically controlled, three-position, four-way hydraulic reversing circuit, achieving a single control action requires simultaneous electrical control of both the three-position, four-way directional valve solenoid and the unloading valve solenoid. Furthermore, a single unloading valve requires the use of multiple, three-position, four-way directional valves, necessitating the construction of relay logic circuits or the use of controllers. This increases control complexity, reduces system reliability, and increases manufacturing costs. Summary of the Invention

[0005] The present invention provides a series-type, three-position, four-way hydraulic reversing circuit with combined action protection. This method employs a main oil circuit without an unloading valve, and the valve core of each three-position, four-way valve is connected in series with the oil supply and return lines. For manual or electronic control, achieving a single control action requires only a single control of each valve core. Furthermore, protection elements are incorporated into each reversing valve to provide combined action protection, preventing the danger of overpressure in actuators caused by accidental combined operation.

[0006] In order to solve the problems in the above-mentioned background technology, the present invention is realized by the following technical solutions: a series-type three-position four-way hydraulic reversing circuit with compound action protection, comprising a plurality of three-position four-way reversing valves, a relief valve, a plurality of one-way valves, an oil inlet pipeline, an oil return pipeline, a main oil supply pipeline, a main oil return pipeline and a plurality of oil ports;

[0007] The multiple three-position four-way reversing valve cores are connected in series through the cooperation of the oil inlet pipeline and the oil return pipeline, and then the two ends are respectively connected to the main oil supply pipeline and the main oil return pipeline to form a loop, and a one-way valve is installed between the oil inlet side pipeline of each three-position four-way reversing valve and the main oil supply pipeline, and an overflow valve is connected at one end of the main oil supply pipeline.

[0008] As a further explanation of the invention: the neutral position function of the three-position four-way reversing valve is not restricted, and the neutral position only needs to ensure the unthrottled connection between the P port and the T port.

[0009] As a further explanation of the invention: the control mode of the three-position four-way reversing valve is not limited to manual control, electric control and manual-electrical control combined type.

[0010] As a further explanation of the invention: the three-position four-way hydraulic reversing circuit includes at least two three-position four-way reversing valves.

[0011] As a further explanation of the invention: the one-way valve is selected to be of no opening pressure type or low opening pressure type.

[0012] Compared with the prior art, the present invention has the following beneficial technical effects:

[0013] 1. The desired action can be controlled through a single manual or electronic control. Manual control is simple and user-friendly, while electronic control can be achieved through simple circuits, significantly reducing control complexity, improving system reliability, and reducing manufacturing costs. Furthermore, the ingenious use of a one-way valve as a protective element provides a high cost-effectiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Figure 1 is a diagram of the prior art structure;

[0015] Figure 2 This is a schematic structural diagram of Example 1 of the present invention;

[0016] Figure 3 This is a schematic structural diagram of Example 2 of the present invention;

[0017] Description of Reference Numerals

[0018] 1. Three-position four-way reversing valve; 2. Unloading valve; 3. Overflow valve; 4. Oil inlet pipeline; 5. Oil return pipeline; 6. Check valve; 7. Main oil supply pipeline. DETAILED DESCRIPTION

[0019] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features therein may be combined with each other.

[0020] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" and the like indicate positions or locations based on the positions shown in the accompanying drawings, or the positions or locations in which the inventive product is typically placed when in use. These terms are intended solely to facilitate the description of the present invention and to simplify the description, and are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third," etc., are used solely to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0021] Furthermore, terms such as "horizontal" and "vertical" do not necessarily mean that a component must be absolutely horizontal or overhanging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted.

[0022] In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0023] Example 1:

[0024] like Figure 2 As shown, a series-type three-position four-way hydraulic reversing circuit with compound action protection includes two three-position four-way reversing valves 1, a relief valve 3, two one-way valves 6, an oil inlet line 4, an oil return line 5, a main oil supply line 7, a main oil return line 5 and two oil ports;

[0025] Specifically, the valve cores of two three-position four-way reversing valves 1 are connected in series through the cooperation of the oil inlet pipeline 4 and the oil return pipeline 5, and then their two ends are respectively connected to the main oil supply pipeline 7 and the main oil return pipeline 5 to form a loop, and a one-way valve 6 is installed between the oil inlet side pipeline of each three-position four-way reversing valve 1 and the main oil supply pipeline 7, and the overflow valve 3 is connected to one end of the main oil supply pipeline 7.

[0026] The series-type three-position four-way hydraulic reversing circuit with compound action protection provided by the present application also includes the use of an M-type three-position four-way valve in this embodiment, but there is no restriction on the neutral position function of the three-position four-way reversing valve 1, and it is only necessary that the neutral position ensures the unthrottled connection between the P port and the T port; and the control form of the three-position four-way reversing valve 1 is not limited to manual control, electric control and manual-electric control composite type; and the three-position four-way hydraulic reversing circuit includes at least two three-position four-way reversing valves 1; the one-way valve 6 is of the no-opening pressure type or the low-opening pressure type.

[0027] Example 2:

[0028] like Figure 2 As shown, a series-type three-position four-way hydraulic reversing circuit with compound action protection includes four three-position four-way reversing valves 1, a relief valve 3, four one-way valves 6, an oil inlet pipeline 4, an oil return pipeline 5, a main oil supply pipeline 7, a main oil return pipeline 5 and four oil ports;

[0029] Specifically, the valve cores of four three-position four-way reversing valves 1 are connected in series through the oil inlet pipeline 4 and the oil return pipeline 5, and then their two ends are respectively connected to the main oil supply pipeline 7 and the main oil return pipeline 5 to form a loop, and a one-way valve 6 is installed between the oil inlet side pipeline of each three-position four-way reversing valve 1 and the main oil supply pipeline 7, and an overflow valve 3 is connected to one end of the main oil supply pipeline 7.

[0030] The series-type three-position four-way hydraulic reversing circuit with compound action protection provided by the present application also includes the use of an M-type three-position four-way valve in this embodiment, but there is no restriction on the neutral position function of the three-position four-way reversing valve 1, and it is only necessary that the neutral position ensures the unthrottled connection between the P port and the T port; and the control form of the three-position four-way reversing valve 1 is not limited to manual control, electric control and manual-electric control composite type; and the three-position four-way hydraulic reversing circuit includes at least two three-position four-way reversing valves 1; the one-way valve 6 is of the no-opening pressure type or the low-opening pressure type.

[0031] Working principle:

[0032] When the hydraulic system is not in operation, the oil returns directly through the series channel formed by the spool of the three-position four-way valve of each link and the inlet and return oil pipelines 5, and the oil source is unloaded. When a certain working link needs to be operated, the spool of the three-position four-way reversing valve 1 is directly pushed to the working position, and then the valve group series channel is divided into two. The oil inlet side of the valve spool of this link becomes the high-pressure oil inlet channel, and the oil return side of the valve spool becomes the low-pressure oil return channel, and the actuator is driven. When the user operates normally and independently, the one-way valve 6 is in the cut-off state. When two or more working links are incorrectly combined, the valve group series passage is divided into three. At this time, the channel between the two working links becomes the middle channel, connecting the return oil of the previous actuator and the inlet oil of the next actuator. During the operation, it is easy to increase pressure. At this time, the one-way valve 6 opens, and the high-pressure oil is directly released into the main oil supply circuit, and then released through the relief valve 3, which plays the role of overpressure protection.

[0033] The present technology is further explained using a four-way, three-position hydraulic reversing circuit embodiment. Figure 3 As shown. This series-type, three-position, four-way hydraulic reversing circuit consists of four circuits, controlling the four hydraulic actuation actions of a certain product. The second and third circuits are driven by hydraulic cylinders. The protection principle for combined actions of the second and third circuits is explained below: From the perspective of the series circuit, oil first enters the third circuit, flows out of the third circuit, and then enters the second circuit. Suppose the cylinder in the second circuit has reached its limit, while the cylinder in the third circuit has not yet reached its limit. At this point, port A3 connects to the large cylinder chamber, and port B3 connects to the small cylinder chamber. When the pressure at port A3 rises to the system relief pressure, due to the difference in area between the two cylinder chambers, a pressurization phenomenon occurs. The pressure on the small chamber side will exceed the system relief pressure, meaning that the pressure in inlet line 4 will exceed the system relief pressure. In severe cases, if the pressure increase ratio is large, the valve body of the three-position, four-way reversing valve 1 and the cylinder body may deform or crack, posing a safety risk. At this time, since a one-way valve 6 is provided between the oil inlet side pipeline of the three-position four-way reversing valve 1 and the main oil supply pipeline 7, it will open when the pressure of the oil inlet side pipeline of the three-position four-way reversing valve 1 is greater than the pressure of the main oil supply pipeline 7, and release the high-pressure oil directly into the main oil supply pipeline, and then release it through the relief valve 3, thus playing the role of boost overpressure protection.

[0034] The above embodiments are preferred examples for implementing the present invention, and the present invention is not limited to the above embodiments. Any non-essential additions or replacements made by those skilled in the art based on the technical features of the present invention fall within the scope of protection of the present invention.

Claims

1. A series three-position four-way hydraulic reversing circuit with compound action protection, characterized by: It comprises a plurality of three-position four-way reversing valves (1), a relief valve (3), a plurality of one-way valves (6), an oil inlet pipeline (4), an oil return pipeline (5), a main oil supply pipeline (7), a main oil return pipeline (5) and a plurality of oil ports; The valve cores of the plurality of three-position four-way reversing valves (1) are connected in series through the oil inlet pipeline (4) and the oil return pipeline (5), and then the two ends thereof are respectively connected to the main oil supply pipeline (7) and the main oil return pipeline (5) to form a loop, and a one-way valve (6) is installed between the oil inlet side pipeline of each three-position four-way reversing valve (1) and the main oil supply pipeline (7), and a relief valve (3) is connected to one end of the main oil supply pipeline (7); the one-way valve (6) will open when the pressure of the oil inlet side pipeline of the three-position four-way reversing valve (1) is greater than the pressure of the main oil supply pipeline, and the high-pressure oil will be directly released into the main oil supply pipeline; The neutral position function of the three-position four-way directional valve (1) is not restricted, and only the neutral position is required to ensure unthrottled communication between the P port and the T port.

2. The series-type three-position four-way hydraulic reversing circuit with compound action protection according to claim 1 is characterized in that: The control mode of the three-position four-way directional valve (1) is manual control, electric control, or a combination of manual and electric control.

3. The series-type three-position four-way hydraulic reversing circuit with compound action protection according to claim 1 is characterized in that: The three-position four-way hydraulic reversing circuit comprises at least two three-position four-way reversing valves (1).

4. The series-type three-position four-way hydraulic reversing circuit with compound action protection according to claim 1 is characterized in that: The one-way valve (6) is selected to be of a no-opening-pressure type or a low-opening-pressure type.

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