JP2002137799A - Propellant tank for artificial satellite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a propellant tank for an artificial satellite manufacturable into a lightweight one at low cost and capable of stably discharging a propellant under a micro-gravity environment. SOLUTION: The propellant tank 1 comprises a trapping structure 20 disposed inside a tank shell 10 having a discharge port 11 therein, the structure comprising four vanes 22 disposed around a trapping container 21 being circular on plan view and having an elliptical cross section, with the trapping container 21 being adjacent to the discharge port 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a propellant tank structure for an artificial satellite used in a microgravity environment such as in orbit around the earth.

[0002]

2. Description of the Related Art In a microgravity environment such as in orbit around the earth, a liquid contained in a tank or the like does not naturally collect on one side (gravity action side) unlike the ground. For this reason, for example, the propellant tank of the attitude control thruster mounted on the satellite has a trapping structure for trapping the liquid (propellant) contained therein and guiding it to the discharge port, and the propellant is propelled from the side opposite to the discharge port. The propellant trapped by the trapping structure is discharged from the discharge port by injecting an inert pressurized gas that does not react with the propellant.

[0003] Such a trapping structure is disclosed in Japanese Unexamined Patent Publication No.
A vane type in which a vane is disposed inside as disclosed in Japanese Patent Application Laid-Open No. 11799, or a channel provided with a mesh as disclosed in Japanese Patent Application Laid-Open No. 9-20299 has a discharge port along an inner peripheral surface. There is known a channel mesh type or the like which is arranged to face.

[0004]

However, in the above-mentioned conventional channel mesh system, the structure is complicated, the production is troublesome, and the cleaning for securing the cleanliness requires time, and the production cost is high. Furthermore, since the mesh is vulnerable to vibration, not only a functional structure but also a structure for securing rigidity is required, and there is a problem in that the weight increases.

The vane type has a relatively simple structure and a low manufacturing cost, but has a large weight, and has a fatal drawback for use in artificial satellites.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is a propellant tank for an artificial satellite that can be manufactured at a low weight and at a low cost and that can stably discharge a propellant under a microgravity environment. The purpose is to provide.

[0007]

According to the present invention, there is provided a propellant tank for an artificial satellite according to the present invention, wherein a small-capacity container-like liquid storage member is provided inside a hollow tank shell having a discharge portion. A communication hole is formed in the container-like liquid storage member at a position close to the inner peripheral surface of the tank shell, and the other end is formed on the outer periphery along the inner surface of the tank shell. A plurality of plate-like vane members extending in the circumferential direction are arranged.

The container-like liquid reservoir member has a circular shape in plan view and a substantially elliptical cross-sectional shape, and is eccentric in the short diameter direction in the tank shell so that the discharge portion is centered on a plane. The suction pipe member is provided in such a manner that the suction pipe member is opened in the vicinity of the inner surface on the peripheral side and connected to the discharge port.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a longitudinal sectional view of a propellant tank for a thruster used for attitude control of an artificial satellite, which is an example of a configuration of a propellant tank for an artificial satellite according to the present invention, and FIG. is there.

The illustrated propellant tank 1 has a hollow spherical tank shell 10 having a predetermined capacity and a discharge port 11 serving as a discharge portion.
And a gas port 12 are provided, and a capturing structure 20 for capturing a propellant therein and guiding the propellant to the discharge port 11 is provided.

The discharge port 11 is disposed at the lower end of the tank shell 10 in the drawing, and the gas port 12 is disposed at the top of the tank symmetrically with the discharge port 11 in the drawing.
The propellant charged in the tank shell 10 is discharged from the discharge port 11 and supplied to a thruster (not shown) by the pressure of the inert extruding gas which does not react with the propellant supplied from the fuel tank 2.

The capture structure 20 is shown in a plan view in FIG.
As shown in a front view in (B) and a bottom view in (C), a vane 22 as a vane member is provided around a trap container 21 as a container-like liquid reservoir member disposed adjacent to the discharge port 11. A plurality is provided and configured.

As shown in FIG. 4 which is an enlarged sectional view and FIG. 5 which is a sectional view taken along the line BB of FIG. , The cross-sectional shape is elliptical, the curvature of the upper and lower peripheral surfaces is smaller than the inner surface curvature of the tank shell 10, and the capacity is, for example, 1 /? It is set as small as possible.

A gas vent 21A is provided at the top in the figure, and a discharge port fitting 23 which opens to the outside and forms a discharge port 11 is fixed at the center in the lower part of the figure. Port fitting 23
Are penetrated through the tank shell 10 and are joined and installed in a state where the outer peripheral surface on the lower side in the figure is in contact with the inner peripheral surface of the tank shell 10. That is, the discharge port 11 does not directly communicate with the inside of the tank shell 10, but communicates with the trap container 21.

In the trap container 21, a plurality of communication holes 21B formed by a plurality of communication holes 21Ba are provided at four locations at equal intervals in the circumferential direction on the lower surface on the outer peripheral side from the contact portion with the inner peripheral surface of the tank shell 10. Mesh members 2 which are formed (ie, at 90 ° intervals in the circumferential direction) and which prevent the passage of gas by the surface tension of the propellant at the formation portions of the communication hole groups 21B.
4 is attached.

In the trap container 21 having the above-described structure, the inside communicates with the inside of the tank shell 10 through the communication hole 21Ba. Therefore, the propellant inside the tank shell 10 flows from the communication hole 21Ba through the trap container 21. 21 and is discharged outside through a discharge port fitting 21B (discharge port 11). In addition, due to the disposition structure, a wedge-shaped space is formed between the outer peripheral surface on the lower side in the figure and the inner peripheral surface of the tank shell 10 and has a tapered cross-sectional shape toward the joint portion. (Communication hole 21B
a) is open toward the wedge-shaped space.

Inside the trap container 21, a cylindrical introduction support tube 25 is erected inside the discharge port fitting 23, and a suction tube 26 is supported by the introduction support tube 25.

The introduction support tube 25 has a predetermined diameter, and the upper end is located substantially at the center of the trap container 21 in the short diameter direction. A plurality of holes communicating with the inside and outside are formed. It is configured. The upper end is reduced in diameter, and the base end of the suction pipe 26 is connected here. A mesh member 28 is also interposed between the lower end of the introduction support tube 25 and the discharge port fitting 23.

The suction pipe 26 has a predetermined diameter and is
A tube having a length reaching the vicinity of the long diameter side periphery is cantilevered at the base end thereof at the upper end of the introduction support tube 25, and four tubes are provided at equal intervals (90 ° intervals) in the circumferential direction. At its tip, a horizontally long rectangular suction port 26A is provided, and a mesh member 29 of a predetermined eye is stretched over the opening of the suction port 26A.

The vane 22 is formed of a thin plate having a predetermined thickness in a tapered arc shape having a predetermined width along the inner surface of the tank shell 10 and a base end of the vane 22 corresponding to the formation position of the communication hole group 21B. It is fixed on the circumferential side. That is, four vanes 22 are provided at equal intervals (90-degree intervals) in the circumferential direction. The outer edge is tank shell 1
0 and a predetermined gap, and the front end reaches the horizontal great circle position of the tank shell 10.

In the propellant tank 1 configured as described above, the propellant filled in the tank shell 10 including the trap container 21 is pressed by the extruded gas supplied from the gas port 12, and Communication hole 2 from inside
The gas enters the trap container 21 through 1Ba and is discharged from the discharge port 11.

In a microgravity environment, the propellant adheres to the inner surface of the tank shell 10 and the trapping structure 20 due to its surface tension, and the tank propellant is discharged as the propellant is discharged.
When the propellant is further reduced, the propellant is trapped by the vane 22 of the trapping structure 20 and retained between the vane 22 and the inner surface of the surrounding tank shell 10 and Flows along the vane toward the wedge-shaped space between the outer peripheral surface of the trap container 21 and the inner peripheral surface of the tank shell 10 and moves into the trap container 21 through the communication hole 21Ba by the pressure of the extruded gas. A mesh member 24 is provided in the communication hole 21Ba. The mesh member 24 separates gas and liquid to prevent the extruded gas from entering the trap container 21. As a result, the propellant moves from the inside of the tank shell 10 to the inside of the trap container 21, and the inside of the trap container 21 always keeps being filled with the propellant as long as there is the propellant in the tank shell 10.

In this manner, the propellant in the tank shell 10 is completely separated in gas-liquid state without leaving any trap container 21.
Can be moved. Here, the four vanes 22 arranged at equal intervals in the circumferential direction are generated by driving the thrusters by matching the directions with the directions of the thrusters for supplying the propellant from the propellant tank 10. Propellant can be efficiently captured by the movement of the propellant by the action of acceleration.

The propellant in the trap container 21 is directly discharged through the introduction support pipe 25 when the propellant remains in the tank shell 10 and fills the trap container 21. When the inside of the tank shell 10 is emptied and the remaining amount in the trap container 21 decreases, the tank shell 10 gathers on a narrow side peripheral portion in the trap container 21 due to its surface tension. The propellant collected on the side periphery can be discharged through the suction pipe 26. In this state, the introduction support tube 25 is exposed in the extruded gas. However, the propellant held by the mesh member 27 separates the gas into gas and liquid and prevents the inflow of the extruded gas into the introduction support tube 25. It is.

In this way, the propellant in the trap container 21 can be completely discharged.

In the above configuration example, four vanes 22 are provided at equal intervals around the trap container 21. However, the positions and number of the vanes 22 are not limited thereto, and can be changed as appropriate.

[0028]

As described above, according to the propellant tank for a satellite according to the present invention, a small-capacity container-like liquid storage member is provided in the hollow tank shell provided with the discharge portion. A communication hole is formed at a position close to the inner peripheral surface of the tank shell, and a plate-like member extending to the other end side along the inner surface of the tank shell on the outer periphery is disposed to face the container. Since a plurality of the vane members are arranged in the circumferential direction, the structure can be simplified and reduced in weight, and can be formed by a combination of parts having a simple shape. In addition, the propellant in the tank shell is caught by the vane member, moves into the container-like liquid reservoir member through the communication hole, and moves to the trap container without leaving the propellant in the tank shell in a gas-liquid separated state. Thus, as long as the propellant is present in the tank shell, the inside of the container-like liquid reservoir member is always kept in a state of being filled with the propellant, whereby the propellant can be stably discharged from the container-like liquid reservoir member.

The container-like liquid reservoir member has a circular shape in plan view and a substantially elliptical cross-sectional shape, and is eccentric in the short diameter direction in the tank shell so that the discharge portion is centered on a plane. The propellant that has been reduced in the container-like liquid reservoir member because the suction pipe member connected to the discharge port and opened to the vicinity of the inner surface on the peripheral side is provided inside the reservoir member. Gather around the periphery,
The remaining propellant can be discharged through the suction pipe member. Thereby, all the charged propellants can be stably and efficiently discharged completely.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a thruster propellant tank used for attitude control of an artificial satellite, which is one configuration example of the artificial satellite propellant tank according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

3A and 3B show a capturing structure, wherein FIG. 3A is a plan view, FIG. 3B is a front view, and FIG. 3C is a bottom view.

4 is an enlarged sectional view of the trap container 2. FIG.

FIG. 5 is a sectional view taken along line BB of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Propellant tank 10 Tank shell 11 Discharge port (discharge part) 20 Capture structure 21 Trap container (container-like liquid storage member) 21Ba communication hole 22 Vane (Vane member)

Claims (2)

[Claims] 1. A small-capacity container-like liquid storage member is provided inside a hollow tank shell provided with a discharge portion so as to face the discharge portion. A communication hole is formed at a position close to the inner peripheral surface of the tank shell, and a plurality of plate-like vane members extending to the other end side along the inner surface of the tank shell are arranged on the outer periphery in the circumferential direction. A propellant tank for a satellite. 2. The liquid reservoir member according to claim 1, wherein said liquid reservoir member has a circular shape in plan view and a substantially elliptical cross section in a predetermined thickness. 2. The artificial satellite propulsion device according to claim 1, wherein a suction pipe member connected to the discharge port is provided in the interior thereof and opened to a vicinity of a peripheral inner surface and connected to the discharge port. Medicine tank.