CN102678680B - Large-capacity hydraulic compensation unit with constant compensation pressure allowance - Google Patents

Abstract

The purpose of the present invention is to provide a large volume constant compensation pressure margin hydraulic compensation unit, including frame, bellows, bellows upper cover plate, bellows bottom plate, integrated valve block, accumulator, hydraulic cylinder, guide column, oil pump , the bellows bottom plate and the guide column are fixed on the frame, the bellows is installed between the bellows upper cover plate and the bellows bottom plate, the guide column passes through the bellows upper cover plate, and when the bellows elastically expands and contracts in the axial direction, the upper bellows The cover plate moves freely along the guide column, the accumulator, the integrated valve block, and the hydraulic cylinder are connected in sequence, the accumulator and the hydraulic cylinder are respectively fixed on the frame, the hydraulic cylinder is connected with the bellows, and the oil suction pipe and the oil return pipe are arranged inside the bellows , the oil pump is connected to the oil suction pipe, and the integrated valve block is connected to the oil return pipe. The invention can not only realize the compensation of the system pressure, but also meet the large volume change of the system oil caused by the asymmetric actuator and leakage in the large hydraulic system, and keep the compensation pressure margin constant.

Description

A Large Volume Constant Compensation Pressure Margin Hydraulic Compensation Unit

technical field

The invention relates to an underwater appliance, specifically an underwater compensator.

Background technique

Underwater hydraulic systems are widely used in marine engineering machinery and underwater scientific investigations, especially large-scale, high-precision deep-water hydraulic systems are more and more widely used. The compensation unit (device) is one of the important links of the underwater hydraulic system. Its function is: to balance the internal and external pressure of the closed structure; to increase the oil return pressure of the system to slightly higher than the ambient pressure (the part higher than the ambient pressure is called the compensation pressure margin) It is used to balance the pressure of the underwater environment and prevent the intrusion of seawater into the system; to compensate the change of the oil volume of the system due to the use of asymmetric actuators and leakage. The main types of existing compensators are piston type, rolling diaphragm type, bellows type, etc. The principle is basically to use elastic elements to transmit seawater pressure, and use spring compression to form a compensation pressure margin. However, for large hydraulic systems, not only the amount of oil leakage is large, but also if a large number of asymmetric actuators such as hydraulic cylinders are used in the system, the volume of oil to be compensated will be large. Due to the spring structure of the existing compensator, when the compensator When the medium oil volume changes greatly, the deformation of the spring also changes greatly, and the corresponding compensation pressure margin changes greatly, which has an adverse effect on the accuracy of the system; when the hydraulic pipeline leaks, the compression of the spring is uncontrollable, resulting in compensation A large amount of oil in the device leaks until the compensation pressure margin becomes zero, and the system cannot perform emergency actions at this time. Due to the limitation of the compensation pressure margin (generally about 0.1MPa), the volume of the existing principle compensator will also be greatly limited, which cannot meet the requirements of large underwater hydraulic systems.

Contents of the invention

The purpose of the present invention is to provide a large volume constant compensation pressure margin hydraulic compensation unit which is applied underwater and ensures a constant compensation pressure margin while providing large volume compensation.

The purpose of the present invention is achieved like this:

The present invention is a large-volume constant compensation pressure margin hydraulic compensation unit, which is characterized in that it includes a frame, a bellows, an upper cover of the bellows, a bottom plate of the bellows, an integrated valve block, an accumulator, a hydraulic cylinder, a guide column, and an oil pump. , the bellows bottom plate and the guide column are fixed on the frame, the bellows is installed between the bellows upper cover plate and the bellows bottom plate, the guide column passes through the bellows upper cover plate, and when the bellows elastically expands and contracts in the axial direction, the upper bellows The cover plate moves freely along the guide column, the accumulator, the integrated valve block, and the hydraulic cylinder are connected in sequence, the accumulator and the hydraulic cylinder are respectively fixed on the frame, the hydraulic cylinder is connected with the bellows, and the oil suction pipe and the oil return pipe are arranged inside the bellows , the oil pump is connected to the oil suction pipe, and the integrated valve block is connected to the oil return pipe.

The present invention may also include:

1. The integrated valve block includes a pressure reducing valve, a check valve, a hydraulic control check valve, a relief valve, an electromagnetic ball valve, and a p chamber. The oil supply circuit of the oil pump is connected to the p chamber through the pressure reducing valve, the check valve, The p chamber is connected with the accumulator and the hydraulic cylinder, the p chamber is connected with the oil suction port of the oil pump through the hydraulic control check valve, the overflow valve, the control oil port of the hydraulic control check valve is connected with the inlet of the pressure reducing valve, and the p chamber is passed through The electromagnetic ball valve is connected with the oil return pipe of the bellows.

2. The oil return pipe is higher than the oil suction pipe, and the upper ends of the oil return pipe and the oil suction pipe are lower than the position of the upper cover plate when the bellows produces the maximum compression.

3. The corrugated pipe is a rubber corrugated pipe, and the end surface of the corrugated pipe mouth is installed with a rectangular ring-shaped metal, and the bellows is installed axially with a circular ring-shaped metal with a cross-sectional area.

4. A quick exhaust valve is installed on the upper cover of the bellows. The hydraulic cylinder is a deep-sea hydraulic cylinder. A displacement sensor is installed inside the hydraulic cylinder. The displacement sensor detects the signal of the oil volume in the bellows and alarms when the oil volume in the bellows is less than the set value. , if the actuator does not move after the alarm and the oil in the bellows continues to decrease, the electromagnetic ball valve will be connected.

The advantage of the present invention is that: the present invention can not only realize the compensation of the system pressure, but also meet the large volume change of the system oil caused by asymmetric actuators and leakage in the large hydraulic system, and keep the compensation pressure margin constant . When the system leaks, an alarm is generated, so that the pressure margin becomes zero, and when the system is repaired and restarted, the compensation pressure margin is restored to prevent the problem that the system cannot be restored or the emergency action cannot be realized due to excessive leakage. Due to its large volume, the compensation unit can even replace the function of the traditional oil source in the system, and can be used as the oil source of the entire system, and can be expanded by connecting multiple compensation units in parallel.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a radial sectional view of the structure at the bellows;

Fig. 3 is a hydraulic principle diagram of the present invention.

Detailed ways

The present invention is described in more detail below in conjunction with accompanying drawing example:

1-3, the present invention includes frame 1, special rubber bellows 3, bellows upper cover plate 4, bellows bottom plate 2, deep-sea hydraulic cylinder 8 with built-in displacement sensor, accumulator 7, integrated valve block 5, guide Compensator unit composed of column 10. It is characterized in that the bellows 3 is connected between the upper cover plate 4 and the bottom plate 2, and the bellows bottom plate 2 is connected with the frame 1; the frame 1 is connected with a plurality of guide columns 10, and the guide columns 10 pass through the upper cover plate 4 of the bellows tube. The guide hole allows the bellows 3 to elastically expand and contract in the axial direction, and the upper cover plate 4 of the bellows moves freely along the guide column 10; one end of the hydraulic cylinder 8 is connected to the frame 1, and the other end is connected to the upper cover plate 4 of the bellows. Connect the accumulator 7, the hydraulic cylinder 8, and the oil supply and return pipelines of the system.

The integrated valve block 5 includes a pressure reducing valve 5.1, a one-way valve 5.2, a hydraulic control one-way valve 5.3, an overflow valve 5.4, and an electromagnetic ball valve 5.5. The oil supply circuit of the system is connected with the p chamber through the pressure reducing valve 5.1, the one-way valve 5.2, and the p chamber is connected with the accumulator 7 and the hydraulic cylinder 8; The oil return circuit is connected to the oil suction port of the oil pump, wherein the control oil port of the hydraulic control check valve 5.3 is connected to the inlet of the pressure reducing valve 5.1; the p cavity is connected to the system oil return circuit through the electromagnetic ball valve 5.5.

There are two kinds of circumferential ring metals 17 and 18 in the special rubber bellows 3, wherein the cross-sectional area of the ring metals 18 at the end face of the bellows 3 is rectangular; The area is circular.

A non-metal bushing 11 is installed in the guide hole of the bellows upper cover plate 4, and the guide post 10 slides relatively in the inner hole of the bushing.

A quick exhaust valve 19 is installed on the upper cover plate 4 of the bellows, and metal blocks 12 and 14 are installed on the bottom plate 2 of the bellows to connect the pipe joint with the oil suction pipe 13 and the oil return pipe 15, wherein the oil return pipe 15 is higher than the oil suction pipe. pipe 13, but the position of the upper end is lower than the position of the upper cover plate 4 when the bellows 3 generates the maximum compression.

The hydraulic cylinder 8 is a special deep-sea hydraulic cylinder with a displacement sensor integrated inside. The displacement sensor transmits the displacement signal to the control system. When the oil volume in the bellows 3 is too small, the control system generates an alarm. If the control system detects that there is no action of the actuator and the oil in the bellows continues to decrease, it is judged that there is leakage in the system oil circuit, and the electromagnetic ball valve is turned on.

The working principle of the present invention is as follows:

As shown in Figure 3, before the system works, the accumulator is filled with nitrogen at a certain pressure, and the set pressure of the overflow valve 5.4 is slightly lower than the set pressure of the pressure reducing valve 5.1. When the system is working, the oil pump provides pressure oil to make the actuator of the hydraulic cylinder move. At the same time, the pressure oil is filled into the P cavity through the pressure reducing valve 5.1 and the check valve 5.2. Since the hydraulic control check valve 5.3 conducts, the control oil port is at high pressure. At this time, the oil The liquid overflows through the relief valve 5.4 so that the pressure of the P chamber is the set pressure of the relief valve. After the oil overflows, it flows into the bellows 3 from the oil port 15; the P chamber communicates with the deep sea hydraulic cylinder 8, so that the hydraulic cylinder 8 generates a constant The accumulator 7 connected to the P chamber can absorb pressure fluctuations, and maintain the P chamber at the set pressure when the oil pump stops supplying oil; the upper end of the hydraulic cylinder is connected to the frame 1, and the lower end acts on the bellows upper cover plate 4 , produces a compression effect on the rubber bellows 3, so that the hydraulic oil in the bellows 3 produces a constant compensation pressure margin, even when the volume of the oil in the bellows 3 changes, the thrust of the hydraulic cylinder 8 always maintains a constant compensation pressure margin Also maintain a constant value; at this time, the ambient pressure acts on the upper cover plate 4 of the compensator at the same time, which compresses the bellows 3 and transmits the pressure to the inside of the bellows 3, so that the internal pressure of the bellows 3 is equal to the ambient pressure and the compensation pressure margin The bellows 3 are respectively connected to the oil suction port of the pump and the oil return line of the hydraulic system through the oil ports 13 and 15, and the oil return pressure is equal to the pressure in the bellows 3. The above process realizes the function of pressure compensation when the hydraulic system is working.

When the asymmetric actuator inside the underwater hydraulic system, such as a hydraulic cylinder, is working, the oil volume inside the bellows 3 will change, which will cause axial elongation or shortening. Due to the guiding effect of multiple guide columns 10, the upper cover plate 4 Drive the bellows 3 to move up and down strictly along the guide column 10. A non-metallic bushing 11 is installed in the guide hole of the upper cover plate 4 of the bellows to reduce friction during relative movement. The above process realizes the function of volume compensation, and it should be pointed out that the compensation pressure always maintains a constant value during this process.

When the system stops working, the oil supply pressure of the oil pump is zero relative to the oil return pressure. At this time, the internal pressure of the accumulator 7 is the same as when the system is working, which is higher than the oil return pressure. Due to the check valve 5.2 and the hydraulic control check valve 5.3 (The low pressure of the control oil port, the hydraulic control check valve cut-off) keeps the pressure of the accumulator 7 constant, the pressure in the hydraulic cylinder 8 connected with it also remains constant, the internal pressure of the corresponding bellows 3 remains constant, and the oil return pressure of the system constant. This process realizes the pressure compensation function when the hydraulic system stops.

When the hydraulic system leaks, the oil inside the bellows 3 continues to decrease, and the bellows 3 shrinks and simultaneously drives the hydraulic cylinder 8 to extend. When the hydraulic cylinder 8 elongates to the warning position, the displacement signal generated by the displacement sensor inside the 8 triggers an alarm . At the same time, the electromagnetic ball valve 5.5 in the integrated valve block is energized, so that the accumulator 7 is connected to the oil return circuit of the system, the pressure of the accumulator 7 is released and equal to the oil return circuit, the hydraulic cylinder 8 becomes floating, and the pressure compensation margin becomes zero , after the system stops, the internal pressure is equal to the ambient pressure, and the leakage will be minimized at this time, waiting for the corresponding emergency measures. After the hydraulic system leak is repaired, the compensation pressure returns to the set value after the system starts up again. In this process, the compensation unit realizes the emergency function of preventing excessive leakage when the hydraulic system leaks, and prevents the situation that the hydraulic oil leakage system cannot be recovered.

It should be noted that the bellows 3 is made of rubber material, and two types of ring-shaped metals 18 and 17 are used inside. The cross-sectional area of the end face of the bellows pipe mouth is a rectangular ring-shaped metal 18, and its function is to The pressure of the bolts is evenly distributed to the sealing surface of the bellows 3, the upper cover plate 4 and the bottom plate 2, so that they fit closely to prevent leakage. 3 Due to the excessive radial deformation caused by the internal pressure, and without increasing the axial compression elastic modulus, the constant compensation pressure margin is guaranteed.

As shown in Figure 2, the function of the quick exhaust valve 19 on the upper cover plate 4 is that the gas will gather on the upper part of the bellows when the system is in trial operation on land, and the gas will be released by adjusting the exhaust valve to avoid affecting the system performance .

Claims (5)

1. A large-volume constant compensation pressure margin hydraulic compensation unit is characterized in that it includes a frame, a bellows, a bellows upper cover, a bellows bottom plate, an integrated valve block, an accumulator, a hydraulic cylinder, a guide column, and an oil pump , the bellows bottom plate and the guide column are fixed on the frame, the bellows is installed between the bellows upper cover plate and the bellows bottom plate, the guide column passes through the bellows upper cover plate, and when the bellows elastically expands and contracts in the axial direction, the upper bellows The cover plate moves freely along the guide column, the accumulator, the integrated valve block, and the hydraulic cylinder are connected in sequence, the accumulator and the hydraulic cylinder are respectively fixed on the frame, the hydraulic cylinder is connected with the bellows, and the oil suction pipe and the oil return pipe are arranged inside the bellows , the oil pump is connected to the oil suction pipe, and the integrated valve block is connected to the oil return pipe; The integrated valve block includes a pressure reducing valve, a one-way valve, a hydraulic control one-way valve, an overflow valve, an electromagnetic ball valve, and a p chamber. It communicates with the accumulator and the hydraulic cylinder, the p chamber is connected with the oil suction port of the oil pump through the hydraulic control check valve, the overflow valve, the control oil port of the hydraulic control check valve is connected with the inlet of the pressure reducing valve, and the p chamber is connected through the electromagnetic ball valve Connected to the oil return pipe of the bellows. 2. A large-volume constant compensation pressure margin hydraulic compensation unit according to claim 1, characterized in that: the oil return pipe is higher than the oil suction pipe, and the upper ends of the oil return pipe and the oil suction pipe are lower than the bellows to generate the maximum The position of the upper cover during compression. 3. A large-volume constant compensation pressure margin hydraulic compensation unit according to claim 1 or 2, characterized in that: the bellows are rubber bellows, and the installation cross-sectional area at the end surface of the bellows is rectangular Ring-shaped metal, the ring-shaped metal with a circular cross-sectional area for the axial installation of the bellows. 4. A large-volume constant compensation pressure margin hydraulic compensation unit according to claim 1 or 2, characterized in that: a quick exhaust valve is installed on the upper cover of the bellows, the hydraulic cylinder is a deep-sea hydraulic cylinder, and the hydraulic pressure A displacement sensor is installed inside the cylinder. The displacement sensor detects the oil volume signal in the bellows. When the oil volume in the bellows is less than the set value, it will alarm. After the alarm, if the actuator does not move and the oil in the bellows continues to decrease, the electromagnetic ball valve will be connected. 5. A large-volume constant compensation pressure margin hydraulic compensation unit according to claim 3, characterized in that: a quick exhaust valve is installed on the upper cover of the bellows, the hydraulic cylinder is a deep-sea hydraulic cylinder, and the inside of the hydraulic cylinder Install the displacement sensor, the displacement sensor detects the oil volume signal in the bellows, and alarms when the oil volume in the bellows is less than the set value, after the alarm, if the actuator does not move and the oil in the bellows continues to decrease, the electromagnetic ball valve is connected.