KR20030056406A - Bellows Reservoir - Google Patents

Abstract

PURPOSE: An oil storing system is provided to improve the operating property and the reliability by eliminating the mechanical friction and corrosion between a piston and a cylinder. CONSTITUTION: An oil storing body(4) stores hydraulic oil. A bellows assembly(1) has recovery force upward the oil storing body. A cover(2) for a gas compartment(2') is combined with the oil storing body and contains the gas compartment. The upper part of the bellows assembly is sealed by a Teflon ring(5). The lower part of the bellows assembly is fixed in a protrusion(9) and a screw portion(2) of the gas compartment by a fixing ring(8). A gas charging valve(3) is installed in the gas compartment between the cover and the bellows assembly. A spring is installed in the gas compartment. Thereby, a bellows type oil storing system reduces the maintenance cost by improving the complexity of a structure and detecting a leakage cycle.

Description

Bellows Reservoir

The present invention relates to a bellows type oil reservoir for use in a closed-loop hydraulic system installed in a moving coordinate system that performs any free motion in a three-dimensional space.

The hydraulic fluid inside the hydraulic system reservoir installed in the moving coordinate system that performs arbitrary free motion in the three-dimensional space is subjected to the combined force by the gravity due to the gravitational field where the moving coordinate system is located and the inertial force of the arbitrary direction motion.

In order to keep the equivalent head of hydraulic oil produced by this synthetic force at all times larger than the effective suction head of the hydraulic pump, that is, to smoothly supply the hydraulic oil required at the pump input port without inflow of air bubbles due to the vacuum state. The operating hydraulic system is a closed loop hydraulic system in which no direct contact between the atmospheric medium and hydraulic oil occurs, and at the same time, a pressurized oil tank is applied.

The role of the oil reservoir in the closed-loop hydraulic system is to store the hydraulic oil required by the system, absorb the volume change generated by the variable-capacity hydraulic components, absorb the volume change due to the thermal expansion of the system oil, and supply the hydraulic oil to the hydraulic pump. Perform.

In order to perform the above role, conventionally, a double piston and a bootstrap type oil tanker applying a cylinder shape and a hydraulic pressure area ratio are applied to the pump's input port to supply hydraulic oil within a predetermined pressure range to prevent vacuum generation and bubble inflow. It was.

Figure 3 shows the general structure of a conventional bootstrap type oil storage unit to match the pressure area ratio of the high pressure piston 11 and the low pressure piston 13 to form the pressure of the hydraulic oil flowing into the pump input port in the low pressure piston (13) and It is structure to keep.

However, the pressurization device for maintaining such a set pressure range not only increases the structure of the low organic matter and leads to an increase in development and manufacturing costs, but also a high pressure piston 11 for pressurization which is generally used as a high pressure pressurization device of the bootstrap type low organic matter. Between the high pressure cylinder 12 and the low pressure piston 13 and the low pressure cylinder 14, a moving sealing member 16 is applied, and the periodic inspection for monitoring and replacing the leakage of oil due to friction and wear as the operation time passes and Periodic replacement is involved.

This not only degrades the operability and reliability of a vehicle or projectile operating a closed-loop hydraulic system equipped with a bootstrap type oil reservoir, but also increases the operating cost.

In the drawings, reference numeral 15 denotes an air filter and an intake / exhaust port, 17 a stationary sealant, 18 a high pressure port, and 19 a pump inlet port.

The present invention serves to supply the hydraulic oil in the pressure range of the hydraulic oil storage and variable volume absorption, the pump input port which is the basic function of the oil reservoir for the closed-loop hydraulic system, in order to solve the disadvantage of the bootstrap oil storage It is to provide a bellows-type oil storage unit which combines a gas pressure compartment structure with a variable-volume receiving non-corrosive bellows assembly which eliminates mechanical friction and abrasion between the piston and the cylindrical pressurization structure and the piston and the cylinder.

The bellows type oil storage device of the present invention is simpler in structure by eliminating the double piston and cylinder shape compared to the existing bootstrap type oil storage device, thereby reducing the development and manufacturing cost and extending the inspection and replacement cycle by removing the moving sealant. It is to improve operability and reliability.

1 is a cross-sectional view of the installation state of the bellows-type oil storage unit of the present invention

Figure 2 is a cross-sectional view of the installation state for another embodiment of the present invention

3 is a state diagram of the installation of known oil storage

[Explanation of symbols on the main parts of the drawings]

1 bellows assembly 2 gas compartment cover

2 ': gas compartment 3: gas filling valve

4: low organic body 5: Teflon ring for exercise guidance

6: stationary sealant 7: threaded portion

8: retaining ring 9: jaw

10: spring

Hereinafter, described in detail with reference to the accompanying drawings.

1 is a cross-sectional view of the installation state of the bellows-type oil storage device of the present invention, the non-corrosive bellows assembly 1 is formed by sealing the upper surface of the non-corrosive bellows operation guide Teflon ring (5), the bottom is a flange It has a shape so that it is fixed to the jaw (9) of the organic body body 4 by a fixing ring (8).

The interior of the bellows assembly 1 is sealedly coupled by the low organic body 4, the threaded portion 7 and the stationary sealant 6 to store the hydraulic fluid.

The space formed between the bellows assembly 1 and the gas compartment cover 2 forms a gas compartment 2 'filled with a chemically stable gas.

When the bellows of the bellows assembly 1 is changed in length, such as a spring, the elastic restoring force and the bellows internal volume due to the equivalent modulus of elasticity are also varied.

The bellows assembly 1 can be compressed and elongated like a spring at the initial neutral position produced by the design value, whereby the bellows assembly generates a restoring force to the neutral position based on the equivalent elastic modulus of the bellows and the law of the hook.

In order to pressurize the hydraulic fluid flowing into the pump and to absorb the hydraulic fluid fluctuations of the variable displacement hydraulic components, the bellows assembly 1 mainly uses the extension region relative to the neutral position.

The hydraulic oil is stored in the bellows assembly 1 and the organic body 4, and is expanded and contracted according to the variation of the volume of the hydraulic oil.

The bellows assembly 1 extended in the initial operation state pressurizes the hydraulic oil stored in the reservoir body 4 and the bellows assembly 1 by the restoring force to transfer the hydraulic oil to the hydraulic pump.

The equivalent elastic force of the bellows assembly 1 can be designed in consideration of the equivalent head of the hydraulic pump by the equivalent synthetic force acting on the hydraulic system installed on the mobile coordinate system and the hydraulic suction head required by the applied pump.

In the case of a large volume change in the applied hydraulic system, that is, when the hydraulic fluid pressurized pressure range by the bellows assembly 1 becomes wide, the gas compartment 2 'between the gas compartment cover 2 and the bellows assembly 1 is improved. The chemically stable gas can be charged to reduce the fluctuation of the hydraulic pressure pressure range.

In this case, the appropriate filling pressure of the gas can be selected and adjusted according to the volumetric fluctuation of the hydraulic system, the elastic modulus of the bellows assembly 1 and the gas state equation of the gas compartment filling gas.

The gas compartment cover 2 is provided with a gas filling valve 3 for filling gas at a set pressure.

The present invention provides a bellows assembly without using the principle of filling gas into the gas compartment 2 'in order to maintain the static pressure to the pump input port and reduce the inlet pressure fluctuation due to the variable volume change of the hydraulic system as shown in FIG. A pressurizing spring 10 is installed between 1) and the gas compartment cover 2 so that an elastic force can be provided in place of the gas pressure so that the gas can be used in combination or there is no gas filling valve 3. It is possible.

As described above, the bellows type oil storage unit, which is the object of the present invention, stores hydraulic oil, which is a basic function of the oil storage unit for a closed-loop hydraulic system installed on a mobile coordinate system that performs arbitrary movement, and absorbs variable volume, and the hydraulic oil having a pressure range set by a pump input port. It is designed to improve the complexity of the structure, which is a disadvantage of the existing bootstrap type oil tanker, and maintenance efforts such as mechanical friction, oil leakage cycle caused by abrasion, and replacement of sealant. Improves operability and reliability.

Claims (4)

An oil storage body (4) in which hydraulic fluid is stored, A bellows assembly (1) having a restoring force on an upper side of the organic body body (4), Bellows-type oil storage unit, characterized in that it is coupled to the oil storage body (4) and consists of a gas compartment cover (2) having a gas compartment (2 ') therein. 2. The bellows assembly (1) according to claim 1, wherein the bellows assembly (1) is sealed upward with a movement guide teflon ring (5) and downwardly with a retaining ring (8) on the jaw (9) and the thread (7) of the gas compartment cover (2). Bellows type oil reservoir, characterized in that fixed with. 2. The gas filling valve (3) according to claim 1, characterized in that a gas filling valve (3) is provided in the gas compartment (2 ') between the gas compartment cover (2) and the bellows assembly (1) for filling a chemically stable gas at a static pressure. Bellows Type Oil Retainer 2. A bellows type oil reservoir according to claim 1, wherein a pressure spring (10) is installed in the gas compartment (2 ') between the bellows assembly (1) and the gas compartment cover (2).