CN203868006U - Hydraulic automatic pressure relieving device - Google Patents

Abstract

The utility model provides a hydraulic automatic pressure relief device. The device is mainly composed of a pilot unloading valve and a small accumulator. It can be conveniently installed in the hydraulic system and is convenient for pressure regulation. An economical, practical and novel combination device for hydraulic components. The utility model is reusable and the pressure can be adjusted, and can be well used to replace the above-mentioned overpressure blasting valve.

Description

Hydraulic automatic pressure relief device

technical field

The utility model relates to a hydraulic automatic pressure relief device, and the technical field involved is the field of mechanical-hydraulic engineering. It is used as a new type of hydraulic component combination device in the aerodynamic braking system of a large-scale fixed-pitch wind power generating set. .

Background technique

At present, the large and extra-large wind turbines at home and abroad are divided into fixed-pitch wind turbines and variable-pitch wind turbines. Their aerodynamic braking systems are different, and the patent "hydraulic automatic pressure relief device" is used in the hydraulic system of the aerodynamic braking system of the fixed-pitch wind turbine. For fixed-pitch wind turbines, the blades of the wind rotor are composed of the main part and the tip part. The tip part can rotate 90° around a longitudinal axis (the tip axis). This rotating part is called the tip spoiler. . When the unit is in normal operation, under the action of the hydraulic cylinder oil pressure of the hydraulic system, the tip spoiler and the main part of the blade are precisely combined to form a complete blade and play the role of absorbing wind energy. When the wind rotor of the fan is overspeed and the electrical control system or hydraulic system of the unit is faulty and requires emergency braking, the oil pressure in the hydraulic cylinder must be quickly and automatically removed, so that the blade tip spoiler rotates 90 degrees rapidly under the action of its centrifugal force °, forming a damping plate to decelerate the fan quickly and ensure the safety of the fan.

At present, many fixed-pitch wind turbines in China have an overpressure burst valve installed in the hydraulic control system for controlling the blade tip spoiler. The pressure rises rapidly, and when the set pressure is reached, the metal diaphragm of the burst valve ruptures, and the oil pressure in the hydraulic cylinder is quickly released, so that the damping plate opens, and the fan decelerates rapidly. The disadvantage of this valve is that it is disposable and cannot be reused. In addition, its burst pressure cannot be adjusted.

Contents of the invention

Purpose of the invention: The utility model provides a hydraulic automatic pressure relief device, which aims to solve the problems of non-reusable and non-adjustable blasting pressure existing in previous devices.

Technical solutions:

A hydraulic automatic pressure relief device, characterized in that: the device includes a connecting block, an unloading valve, an accumulator, an oil discharge valve and a pressure measuring joint; the unloading valve is fixed on the connecting block, and the accumulator is connected with a pipe joint The connecting block is connected, and the oil discharge valve adopts a plug-in throttle valve, which is connected with the connecting block in a threaded manner, and the pressure measuring joint is directly screwed into the connecting block.

The unloading valve is equipped with an oil passage, a plunger, a pilot valve, a check valve and a main valve core. The oil passage includes a main oil passage, a control oil passage and an oil return passage. The main oil passage and the control oil passage The channel and the oil return channel are connected. On the one hand, the control oil channel is connected to the inlet of the accumulator, the pressure measuring joint and the oil discharge valve through the outlet, and on the other hand, it is connected to the left cavity of the plunger. A one-way valve is installed on the pipeline before the outlet of the valve and the plunger; the right cavity of the plunger communicates with the left cavity of the pilot valve, and the pilot valve is set on the oil return channel to control the opening and closing of the oil return channel, and the oil return channel passes through the The unloading valve has an oil return port at both ends, one oil return port is connected to the oil return tank, the other oil return port is connected to the outlet of the oil discharge valve, and the pilot valve is set at the position connected to the outlet of the oil discharge valve;

The main oil channel is in communication with the right chamber of the plunger. A main valve core is set at the entrance of the main oil channel leading to the oil return channel to control the opening and closing of the inlet. A damping hole is arranged in the main valve core. The damping hole is connected with the The right cavity of the plunger communicates.

Advantages and effects: The utility model provides a hydraulic automatic pressure relief device, which is mainly composed of a pilot unloading valve and a small accumulator, which can be conveniently installed in the hydraulic system and adjust the pressure. It is convenient, and is an economical, practical, and novel combination device for hydraulic components.

The utility model is reusable and the pressure can be adjusted, and can be well used to replace the above-mentioned overpressure blasting valve.

Description of drawings:

Fig. 1 is the structural representation of the utility model;

Fig. 2 is the oil circuit diagram of the utility model;

Fig. 3 is the left view of Fig. 1;

FIG. 4 is a top view of FIG. 3 .

The specific embodiment: the utility model is further described below in conjunction with the accompanying drawings:

As shown in Figure 1, the utility model provides a hydraulic automatic pressure relief device, which includes a connecting block 1, an unloading valve 2, an accumulator 3, an oil discharge valve 4 and a pressure measuring joint 5; the unloading valve 2 is fixed On the connection block 1, the accumulator 3 is connected with the connection block 1 by a pipe joint, the oil discharge valve 4 is a plug-in throttle valve, and is connected with the connection block 1 in a threaded manner, and the pressure measuring joint 5 is directly screwed into the connection block 1 superior. Connection block 1 has four fixing screw holes.

As shown in Figure 2, the unloading valve 2 is provided with an oil channel, a plunger 7, a pilot valve 10, a check valve 6 and a main valve core 8, and the oil channel includes a main oil channel, a control oil channel and a return valve. The oil passage, the main oil passage, the control oil passage and the oil return passage are connected through corresponding valves. On the one hand, the control oil passage is connected to the inlet of the accumulator 3, the pressure measuring joint 5 and the oil discharge valve 4 through the outlet B. On the other hand, it communicates with the left cavity of the plunger 7, and the check valve 6 is set on the pipeline before the control oil channel leads to the outlet B of the check valve and the plunger 7; The cavity is connected, the pilot valve 10 is set on the oil return channel to control the opening and closing of the oil return channel, the oil return channel passes through the unloading valve 2 and has an oil return port O at both ends, and one oil return port is connected to the oil return tank 12, The other oil return port communicates with the outlet of the oil drain valve 4, and the pilot valve 10 is set at a position communicated with the outlet of the oil drain valve 4;

The main oil channel communicates with the right cavity of the plunger 7, and the main oil channel leading to the oil return channel is provided with a main valve core 8 which controls the opening and closing of the inlet, and a damping hole 9 is provided in the main valve core 8 , The damping hole 9 communicates with the right chamber of the plunger 7.

Figure 2 is the hydraulic oil circuit diagram of the device. The oil in the high-pressure chamber 13 of the hydraulic cylinder that drives the blade tip spoiler is connected to the inlet P of the main oil circuit channel of the unloading valve through the connecting block, and the oil return of the unloading valve Port O communicates with the oil return tank 12 through the connection block.

Working principle: This device is an automatic pressure relief valve group. Its function is that when the pressure of the high pressure chamber 13 exceeds the set pressure value of the pressure regulating spring, the unloading valve will automatically overflow without pressure, completely making the high pressure chamber decompression.

It can be seen from Figure 2 that the oil at the inlet P of the main oil channel is divided into two paths, one path goes to the one-way valve 6, and after it comes out, it goes to the left chamber of the plunger 7 and enters the accumulator 3, and the other path passes through the main valve core 8. Damping hole 9 to the left chamber of the pilot valve 10 and the right chamber of the plunger 7; when the oil pressure in the high pressure chamber rises, but has not yet reached the set pressure value of the pressure regulating spring 11, the pilot valve 10 is not opened at this time, the main The spool 8 is in the closed state under the force of the return spring, and the plunger 7 is also in a balanced state; When the pilot valve 10 is opened, the oil in the high-pressure chamber passes through the damping hole 9 of the main valve core 8 to the valve port of the pilot valve 10 and flows back to the O cavity. There is a pressure difference, so the main valve core 8 is opened, and the left and right ends of the plunger 7 also have a pressure difference due to the opening of the pilot valve 10, and the effective area of the plunger 7 is larger than that of the pilot pilot valve 10. Open the pilot valve 10 When the effective area of the valve 10 is opened, the plunger 7 exerts additional force on the pilot valve 10, and its force is greater than the set pressure value of the pressure regulating spring 11, thus increasing the opening of the pilot valve 10, so that the main valve The opening of core 8 is the largest, and the oil in the high-pressure chamber overflows without pressure. Since the hydraulic oil entering the accumulator 3 has no leakage and the oil pressure is always maintained, the extra force of the plunger 7 always exists, so the opening of the main valve core 8 is always open, and the opening amount is the largest, thus reaching the high pressure chamber. The purpose of complete decompression.

Features of this application

1) It is an automatic safety protection device. When the wind rotor of the wind turbine is overspeed and the electrical control system fails, the damping plate of the fan blade tip spoiler will be automatically opened through the pressure relief of the device, so that the fan will automatically decelerate and brake ;

2) Compared with the super-pressure blasting valve, this device can be reused (open the oil release valve to release the oil in the accumulator 3 and the device will reset), and the unloading pressure can be adjusted conveniently, which is very practical;

3) The device has a compact and novel structure, adopts standard components, works reliably, and is easy to manufacture and install;

4) This device can expand the scope of application and be used in the field of complete pressure relief of pressure vessels.

Claims (2)

1. a hydraulic pressure automatic pressure relief device, is characterized in that: this device comprises contiguous block (1), unloading valve (2), accumulator (3), fuel outlet valve (4) and pressure measuring tie-in (5); Unloading valve (2) is fixed on contiguous block (1), accumulator (3) utilizes pipe joint to be connected with contiguous block (1), fuel outlet valve (4) adopts cartridge throttle valve, is connected threadably with contiguous block (1), and pressure measuring tie-in (5) directly screws on contiguous block (1).

2. hydraulic pressure automatic pressure relief device according to claim 1, it is characterized in that: unloading valve is provided with asphalt channel in (2), plunger (7), pilot valve (10), one-way valve (6) and main valve plug (8), asphalt channel comprises main oil channel channel, oil circuit control passage and drainback passage, main oil channel channel is communicated with oil circuit control passage and drainback passage, oil circuit control passage is on the one hand by outlet (B) and accumulator (3), the entrance of pressure measuring tie-in (5) and fuel outlet valve (4) connects, be communicated with the left chamber of plunger (7) on the other hand, at oil circuit control passage, lead on one-way valve outlet (B) and plunger (7) pipeline before one-way valve (6) is set, the right chamber of plunger (7) is communicated with the left chamber of pilot valve (10), pilot valve (10) is arranged on drainback passage, control the switching of drainback passage, drainback passage is through unloading valve (2) and at two ends, respectively have a return opening (O), a return opening is connected to oil sump tank (12), another return opening is communicated with the outlet of fuel outlet valve (4), and pilot valve (10) is arranged on the position being communicated with the outlet of fuel outlet valve (4),

Main oil channel channel is communicated with the right chamber of plunger (7), the ingress that leads to drainback passage at main oil channel channel is provided with the main valve plug (8) of controlling this entrance switching, in main valve plug (8), be provided with damping hole (9), damping hole (9) is communicated with the right chamber of plunger (7).