Pilot operated proportional relief valve

Abstract

The utility model belongs to mechanical hydraulic pressure field relates to a pilot type proportional overflow valve, including pilot proportional valve, highest pressure limiting valve, main valve body and check valve plate, check valve plate is placed between highest pressure limiting valve and main valve body, highest pressure limiting valve is linked with main valve body through check valve plate, the utility model provides a pilot type proportional overflow valve which is not affected by pressure oil port pressure fluctuation in whole pressure regulating process and then ensures proportional overflow valve pressure regulating process system pressure stability.

Description

Technical Field

[0001] This utility model belongs to the field of hydraulic machinery and relates to a proportional relief valve, and more particularly to a pilot-operated proportional relief valve. Background Technology

[0002] See Figure 1 This is a common type of pilot-operated proportional relief valve structure on the market, consisting of a pilot proportional valve 1, a maximum pressure relief valve 2, and a main valve body 3. The pilot proportional valve 1 is connected to the main valve body 3 via the maximum pressure relief valve 2, employing internal pilot control. Because the pressure of the pilot pressure oil entering through the main valve body pressure oil passage 32 via the main valve body 3 can rise or fall, resulting in pressure fluctuations, therefore... Figure 1 When the pilot-operated proportional relief valve shown is in operation, it will cause pressure fluctuations in the proportional relief valve. For hydraulic systems with high pressure accuracy requirements, this pilot-operated proportional relief valve cannot meet the usage requirements. Utility Model Content

[0003] In order to solve the above-mentioned technical problems in the background art, the present invention provides a pilot-operated proportional relief valve that is not affected by pressure fluctuations at the pressure port during the entire pressure regulation process, thereby ensuring the stability of system pressure during the proportional relief valve pressure regulation process.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A pilot-operated proportional relief valve includes a pilot-operated proportional valve, a maximum pressure relief valve, and a main valve body, characterized in that: the pilot-operated proportional relief valve further includes a one-way valve plate; the one-way valve plate is placed between the maximum pressure relief valve and the main valve body; the maximum pressure relief valve is connected to the main valve body through the one-way valve plate.

[0006] The aforementioned one-way valve plate includes a one-way valve; the maximum pressure relief valve is connected to the main valve body through the one-way valve.

[0007] The aforementioned maximum pressure relief valve includes a load port pilot oil passage, and the main valve body includes an internal control oil passage; the load port pilot oil passage is connected to the internal control oil passage through a check valve.

[0008] The aforementioned one-way valve plate includes a first channel; the one-way valve is placed in the first channel.

[0009] The aforementioned maximum pressure relief valve also includes a main valve core pilot oil channel, the main valve body also includes a main valve body pressure oil channel, and the one-way valve plate also includes a second channel; the main valve core pilot oil channel is connected to the main valve body pressure oil channel through the second channel; the second channel is parallel to the first channel.

[0010] The aforementioned maximum pressure relief valve also includes a pilot oil drain channel, the main valve body also includes a main valve body drain channel, and the one-way valve plate also includes a third channel; the pilot oil drain channel is connected to the main valve body drain channel through the third channel; the third channel is parallel to the first channel.

[0011] The advantages of this utility model are:

[0012] This invention provides a pilot-operated proportional relief valve, including a pilot proportional valve, a maximum pressure limiting valve, and a main valve body. The pilot proportional valve is connected to the main valve body via the maximum pressure limiting valve. Additionally, a one-way valve plate is added between the maximum pressure limiting valve and the main valve body; the maximum pressure limiting valve is also connected to the main valve body via the one-way valve plate. In use, when the pressure of the pilot pressure oil in the main valve body increases, the pilot pressure oil squeezes and opens the one-way valve plate, ultimately flowing into the pilot proportional valve through the maximum pressure limiting valve, thus acting as a buffer. Simultaneously, when the pressure of the pilot pressure oil in the main valve body suddenly decreases, the one-way valve plate closes the pilot pressure oil in one direction, ensuring that the pressure of the pilot pressure oil about to flow into the pilot proportional valve through the maximum pressure limiting valve does not suddenly decrease. This ensures that the proportional relief valve is not affected by pressure fluctuations at the pressure ports during the entire pressure regulation process. Clearly, this invention can improve the unstable operation of the proportional relief valve during pressure regulation caused by numerous pressure fluctuations, ensuring stable system pressure and reliable operation during the proportional relief valve's pressure regulation process. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the pilot-operated proportional relief valve used in existing technology;

[0014] Figure 2 This is a schematic diagram of the pilot-operated proportional relief valve used in this utility model;

[0015] in:

[0016] 1-Pilot proportional valve; 2-Maximum pressure relief valve; 21-Load port pilot oil passage; 22-Main valve core pilot oil passage; 23-Pilot oil drain passage; 3-Main valve body; 31-Internal control oil passage; 32-Main valve body pressure oil passage; 33-Main valve body drain passage; 4-Check valve plate; 41-First passage; 42-Second passage; 43-Third passage; 44-Check valve. Detailed Implementation

[0017] See Figure 2This utility model provides a pilot-operated proportional relief valve, which, like the prior art, includes a pilot proportional valve 1, a maximum pressure relief valve 2, and a main valve body 3. The pilot proportional valve 1 is connected to the main valve body 3 through the maximum pressure relief valve 2. Unlike the prior art, this utility model adds a one-way valve plate 4 between the maximum pressure relief valve 2 and the main valve body 3. The maximum pressure relief valve 2 is connected to the main valve body 3 through the one-way valve plate 4. In use, when the pressure of the pilot pressure oil in the main valve body 3 increases, the pilot pressure oil squeezes and opens the one-way valve plate 4, and finally flows into the pilot proportional valve 1 through the maximum pressure relief valve 2, which plays a buffering role. At the same time, when the pressure of the pilot pressure oil in the main valve body 3 suddenly decreases, the one-way valve plate 4 closes the pilot pressure oil in one direction, ensuring that the pressure of the pilot pressure oil that is about to flow into the pilot proportional valve 1 through the maximum pressure relief valve 2 will not suddenly decrease. This ensures that the proportional relief valve is not affected by the pressure fluctuation of the pressure oil port during the entire pressure regulation process. Obviously, this utility model can improve the unstable operation of the proportional relief valve caused by pressure fluctuations during the pressure regulation process, and ensure that the system pressure is stable and the operation is reliable during the pressure regulation process of the proportional relief valve.

[0018] See Figure 2 For example, the one-way valve plate 4 used in this utility model includes a one-way valve 44; the maximum pressure limiting valve 2 is connected to the main valve body 3 through the one-way valve 44. The maximum pressure limiting valve 2 includes a load port pilot oil channel 21, and the main valve body 3 includes an internal control oil passage 31; the load port pilot oil channel 21 is connected to the internal control oil passage 31 through the one-way valve 44. For example, the one-way valve plate 4 includes a first passage 41; the one-way valve 44 is placed in the first passage 41. The first passage 41 has a step that cooperates with the one-way valve. When the pilot pressure oil squeezes the one-way valve 44, the one-way valve 44 gradually moves away from the step, causing the one-way valve 44 and the first passage 41 to form an oil passage so that the pilot pressure oil can pass through; when the pressure of the pilot pressure oil in the main valve body 3 suddenly decreases, due to the action of the one-way valve 44, the pressure of the pilot pressure oil is insufficient to squeeze and cause the one-way valve 44 to gradually move away from the step, thereby blocking the low-pressure pilot pressure oil.

[0019] Meanwhile, the maximum pressure relief valve 2 also includes a main valve core pilot oil channel 22, the main valve body 3 also includes a main valve body pressure oil channel 32, and the check valve plate 4 also includes a second channel 42; the main valve core pilot oil channel 22 is connected to the main valve body pressure oil channel 32 through the second channel 42; the second channel 42 is parallel to the first channel 41. The maximum pressure relief valve 2 also includes a pilot oil drain channel 23, the main valve body 3 also includes a main valve body drain channel 33, and the check valve plate 4 also includes a third channel 43; the pilot oil drain channel 23 is connected to the main valve body drain channel 33 through the third channel 43; the third channel 43 is parallel to the first channel 41.

[0020] This utility model is... Figure 1A one-way valve plate 4 is added to the main valve body 3 of the pilot-operated proportional relief valve shown. A one-way valve 44 is added to the internal control oil passage 31 and the pilot oil passage 21 of the load port. When the pressure at the main valve body pressure oil passage 32 of the main valve body 3 is high, the pilot pressure oil first passes through the one-way valve 44. When the pressure of the pilot pressure oil at the main valve body pressure oil passage 32 of the main valve body 3 suddenly drops, the pilot pressure oil is blocked by the action of the one-way valve 44, ensuring that the pilot pressure will not drop suddenly. In this way, the proportional relief valve is not affected by the pressure fluctuation of the pressure oil port during the entire pressure regulation process.

Claims

1. A pilot-operated proportional relief valve, comprising a pilot-operated proportional valve (1), a maximum pressure relief valve (2), and a main valve body (3), characterized in that: The pilot-operated proportional relief valve also includes a one-way valve plate (4); the one-way valve plate (4) is placed between the maximum pressure relief valve (2) and the main valve body (3); the maximum pressure relief valve (2) is connected to the main valve body (3) through the one-way valve plate (4).

2. The pilot-operated proportional relief valve according to claim 1, characterized in that: The one-way valve plate (4) includes a one-way valve (44); the maximum pressure relief valve (2) is connected to the main valve body (3) through the one-way valve (44).

3. The pilot-operated proportional relief valve according to claim 2, characterized in that: The maximum pressure relief valve (2) includes a load port pilot oil channel (21), and the main valve body (3) includes an internal control oil passage (31); the load port pilot oil channel (21) is connected to the internal control oil passage (31) through a check valve (44).

4. The pilot-operated proportional relief valve according to claim 3, characterized in that: The one-way valve plate (4) includes a first channel (41); the one-way valve (44) is placed in the first channel (41).

5. The pilot-operated proportional relief valve according to claim 4, characterized in that: The maximum pressure relief valve (2) further includes a main valve core pilot oil channel (22), the main valve body (3) further includes a main valve body pressure oil channel (32), and the one-way valve plate (4) further includes a second channel (42); the main valve core pilot oil channel (22) is connected to the main valve body pressure oil channel (32) through the second channel (42); the second channel (42) is parallel to the first channel (41).

6. The pilot operated proportional relief valve of claim 5, wherein: The maximum pressure relief valve (2) also includes a pilot oil drain channel (23), the main valve body (3) also includes a main valve body drain channel (33), and the one-way valve plate (4) also includes a third channel (43); the pilot oil drain channel (23) is connected to the main valve body drain channel (33) through the third channel (43); the third channel (43) is parallel to the first channel (41).

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