JP2552619B2 - Method and apparatus for pressure forming flexible film surface - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The disclosed technology belongs to the field of technology for forming a flexible film surface used for a space and a ground inflatable antenna or a reflecting surface of a solar concentrator by gas pressure.

[0002]

2. Description of the Related Art As is well known, the rise of modern civilization depends largely on the development of science and technology, and the development on a global scale such as the effective use of natural resources has reached its limit, and there is no end to this research. Development has reached beyond the Earth's sphere and has recently reached outer space.

Since the inflatable antenna and the solar concentrator are light in weight and have good storability and surface accuracy, they are promising candidates for future large-scale reflectors for space, and not only in space. We are considering application for ground use.

Thus, the surfaces of the antenna, the sunlight concentrator, and the like are required to have extremely mathematical precision due to the reflection of radio waves, and particularly when the film surface is formed by gas pressure, The pressurization control is extremely delicate, and it has been difficult to achieve efficient molding though it is theoretically possible to perform complicated detection work and molding via a control device.

As a conventional technique, Japanese Patent Laid-Open No. 2-1018
There is a 03 publication.

[0006]

By the way, the flexible film surface of the antenna or the like of the inflatable reflector is usually a spherical shape or a parabolic quadric surface in view of the capacity of the dome and the performance of the reflecting surface of the antenna. It is supposed to be.

Therefore, the flexible membrane surface 1 (see FIGS. 1 and 2) is always in the normal direction of the flexible membrane surface at a technical level in which the relationship between the change in the normal direction and the gas pressure cannot be calculated in advance. The radius must be detected at the desired timing via the positioning sensor, and the output control must be performed based on this detection, and the rate of pressurization of the gas pressure and the rate of increase in the center height of the flexible membrane cannot be grasped in advance. However, there was a drawback that an efficient sequence could not be assembled.

Even if the detection sensor can position the center point of the flexible film surface in the z-axis direction and the corresponding gas pressure can be detected by the appropriate gas pressure sensor,
A high frequency test is required to obtain the calibration curve, and there is an inconvenience that the test for obtaining the calibration curve causes troublesome construction and high cost.

[0009]

OBJECT OF THE INVENTION The object of the invention of this application is to solve the problem of pressure molding by gas pressure of an inflatable reflector applied to a space antenna, a solar concentrator or the like based on the above-mentioned prior art, Detects the amount of deformation of the film surface,
Furthermore, by calculating the relationship between the amount of deformation and the gas pressure using a mathematical formula, the amount of pressurized gas is adjusted so that pressure control by gas pressure can be reliably performed. It is intended to provide a method and a device used directly in the method.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the structure of the invention of the present application, which has the above-mentioned object as its gist, has a predetermined rigidity in order to solve the above-mentioned problems. It is fixed in a sealed state to a supporting structure having, and with respect to the flexible membrane surface having an initial predetermined spherical shape through the supporting structure,
A predetermined gas and a predetermined volume of gas are supplied from the inside through a rough adjustment pipe, and the detection piece provided on the flexible membrane surface supports the displacement of the flexible membrane surface in the normal direction so as to face the detection piece. The equilibrium condition of the potential energy of the flexible membrane surface is detected using the computer of the control device that inputs the membrane surface data such as the Young's modulus and Poisson's ratio of the flexible membrane surface detected by the positioning sensor provided through the bracket. Calculate the relationship of the pressure corresponding to the amount of displacement in the normal direction by a preset calculation formula using
Also, the technical means is provided to control the gas pressure supply through the pressure sensor by the fine adjustment pipe so that the flexible membrane surface can be pressure-molded.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following will describe one embodiment of the invention of this application with reference to FIGS.

The illustrated embodiment shows a form of an inflatable reflector, and one unit is shown in the drawing, but a plurality of similar units may be combined to form a reflector.

[0013] Then, in the stage before the operation, it is compactly housed, and is put into the operation form by assembling / developing / expanding.

The film surface is formed by pressurizing and depressurizing the gas pressure with a predetermined inert gas or the like, and the optimum shape is the gas pressure measurement under the correlation condition by the shape detection. It is obtained by controlling the gas pressure via

In particular, when used for space, a reflector may be assembled / deployed by using a curable material for the film surface, the film surface may be expanded under pressure, and then the reflector surface may be cured by sunlight or the like. Conceivable.

Thus, in this mode, the gas pressure control is not direct detection of the gas pressure but direct shape detection and simple measurement based on a simple calculation formula expressing the relationship between the displacement amount and the pressure. The measurement is performed by indirect measurement, and the control is managed by an extremely simple method, the operation is easy, and the cost is low.

The principle aspect of the invention of this application will be described with reference to FIG. 2. The flexible film surface 1 is made of a predetermined synthetic resin, and the setting metal material is mirror-deposited on the surface thereof. It has a pressure t, a Poisson's ratio ν, and a Young's modulus E, and its periphery is fixed in a sealed state on a rigid supporting structure 2 of a predetermined housing type, and a predetermined inert gas is pressurized from the inside by a pressure P. It is designed to be applied.

The film surface before deformation has a shallow spherical shape with a predetermined depth, and the center height h of the film surface is smaller than the radius of curvature R before and after the pressurization before and after the pressurization. To do.

The shallow spherical film surface 1 having a predetermined depth is subjected to pressure control (not shown) and a computer of a display device to obtain data (diameter: 2a, center height h ₀ , data of the film surface before pressure deformation). Young's modulus E, membrane pressure t, Poisson's ratio ν, etc.) are input.

As described above, it has been found that there is a correlation between the change in shape of the flexible membrane surface having a predetermined spherical shape before deformation due to the pressure forming and the gas pressure.

As shown in FIG. 2, when the height of the center point P _c of the spherical flexible film surface 1 is pressurized by gas pressure from the position h _o before the pressing to the position h _M by gas pressure, the deformed shape is several. 4, when the equilibrium condition of the potential energy of the flexible membrane surface is used, the relationship between the displacement w _{c of} the central point from the state before pressurization, the pressure P, etc. is simplified by Equations 5 and 6. However, it can be obtained extremely accurately.

[0022]

[Equation 4]

[0023]

F ₁ [(R / a · w _c / a) ⁻¹ , n, ν] = 0

[0024]

(Equation 6) However, P: pressure a: distance from the z-axis of the end part w _c : center point displacement (z direction) w ₀ : W _c / a w: normal direction displacement ν: Poisson's ratio v: tangential displacement n: change Parameter r: Distance from the z-axis c ₁ : Change parameter c ₂ : Change parameter R: Spherical radius of curvature (before deformation) E: Young's modulus of film f ₁ , f ₂ : Determined from equilibrium condition [R / a · w _c / A]
⁻¹ quadratic equation t: film thickness, and by setting one of the three parameters P, w ₀ , and n, the other two are used to set the pressure of the molding pressurizing gas. You can

In the invention of this application, the shallow spherical flexible film surface also includes a planar film.

It should be noted that the above equations 4, 5 and 6 are ready to be submitted as calculation data.

When R, a, ν, E, and t are given in the calculation of the equations 4, 5 and 6, and n is eliminated from the equations 5, 6, the pressure P and the z of the center point P _c are reduced. The relationship with the axial displacement w _c is obtained, and the gas pressure P corresponding to the z axial displacement w _c of the center point P _c is obtained.

Therefore, the above equations (4), (5), (6), parameters as the film surface data, etc. are inputted in advance to the computer of the gas pressure control device, and the position of the center point P _c of the film surface 1 in the z-axis direction. As long as w _c is detected by an appropriate sensor and the detection data is input, the corresponding gas pressure P is immediately calculated and measured, and if the gas pressure is controlled and supplied by an appropriate optimizing means, the inflatable reflector as designed can be obtained. The flexible film surface 1 can be pressure-molded into a predetermined shape and size.

Of course, the height of the center point P _c of the flexible membrane surface 1 is set to h
_The pressure P _M required to change the pressure from _{0 to} h _M can be calculated in advance, and the relationship between h and P at an intermediate stage can be calculated.

Further, the pressurization time Δt _M of the gas can be calculated, and, of course, the display thereof is also possible.

Then, as will be described below, a stepped or stepless control sequence of the pressurizing speed of the gas pressure can be assembled in advance.

In this way, when coarse accuracy is allowed, a test for obtaining a calibration curve is unnecessary and handling becomes easy.

Further, when extremely high accuracy is required, the work becomes easy even when it is necessary to create it by a calibration curve.

Next, an embodiment according to the above-described principle mode will be described with reference to FIG.

The same parts as in FIG. 2 will be described using the same reference numerals.

The flexible film surface 1 made of a predetermined resin is vapor-deposited on its mirror surface, and its peripheral edge 1'is fixed in a sealed state to a support structure housing 2 having a predetermined strength and rigidity. A detection piece 3 for detecting a displacement of the flexible film surface 1 in the z-axis direction, that is, in the normal direction of the central portion is provided, and at a portion facing the detection piece 3, for example, a proximity switch type positioning sensor 4 is provided. It is fixed to the housing 2 via an appropriate bracket or the like.

Further, a gas supply pipe 5 is provided at the lower part of the housing 2 and extends therefrom.
Is composed of a coarse adjustment pipe 5 ′ and a fine adjustment pipe 5 ″, and is connected to the gas feed pump 6.

A predetermined diaphragm 7 is inserted in the fine adjustment pipe 5 ''.

Reference numeral 8 is a gas pressure control / display device, and a predetermined pressure control device 9, a display device 10, and a recording device 11 are controlled by a computer 12.

An appropriate gas pressure detection sensor 13 is provided in the housing 2 and is electrically connected to the pressure control device 9.

The positioning sensor 4 is also electrically connected to the gas pressure control / display device 8.

Then, the computer 12 is preliminarily inputted with the membrane surface data such as Young's modulus and Poisson's ratio of the flexible membrane surface 1, and the formulas (4), (5) and (6) are inputted and predetermined. Is calculated by the program and the supply gas pressure is controlled.

Thus, the above-mentioned plant can be installed on the ground or in space according to the technology established so far, and the management, control, and operation of the equipment are difficult due to the conventional software. It will be lost.

In the above-described structure, when the inflatable reflector is expanded and formed by gas pressure to a predetermined shape size, the flexible film surface 1 is pre-input as described above and the flexible film surface data and the equation 4 ，
A predetermined inert gas is pressure-fed from the feed pipe 5 into the housing 2 via the computer 12 by the pressure control device 9 according to the mathematical formulas of the equations 5 and 6, and the gas pressure is linearly detected by the gas pressure detection sensor 13. .

Then, as described above, the computer 1 is previously used.
The gas is supplied under optimal control according to the film surface data input to 2, but the coarse adjustment feed pipe until the detection piece 4 first comes close to the positioning sensor 4 by the feedback of the detection pressure from the gas pressure detection sensor 13. Gas is supplied by 5'to bulge the flexible membrane surface 1.

In this case, in the process in which the flexible film surface swells to the design molding size by the gas pressure detection sensor 13,
The gas is applied by the coarse adjustment feed pipe 5'to about 90% of the design pressure, but when the feed gas pressure exceeds 90%, for example, the fine adjustment feed pipe 5 '' passes through the throttle 7 through the throttle 7. The bulging molding of the flexible film surface 1 is performed while finely adjusting.

Of course, at this time, the flexible membrane surface 1 is set to the set size shape through the calculation calculation through the computer 12 by the above-mentioned equations 4, 5, and 6 based on the position data of the detection piece 3 with respect to the positioning sensor 4. The calculation of pressure as it is molded is done automatically.

When the set size shape of the flexible film surface 1 is formed, the gas supply is automatically stopped, and the data during this period is recorded in the recording device 11 and the display device 10 is also recorded.
It is displayed on and is used for control management.

Note that the pressurization time Δt _M calculation display can also be performed in advance while moving.

In the present embodiment, the flexible membrane surface 1
Since h / R << 1 in the spherical film of, the simple calculation is performed based on the parameters by the equations (4), (5), and (6) described above, and the calculation is performed very smoothly by the computer 12. If the output control is performed with relatively good accuracy and high accuracy is not required, a test or the like for obtaining the calibration curve becomes unnecessary.

However, when extremely high accuracy is required, it is necessary to prepare a calibration curve by a test. In this case, the work is easy because the ratio between the calibration value and the calculated value is extremely close to 1. Is.

The target flexible membrane surface 1 can be used not only for ground and space inflatable reflectors but also for facilities such as a dome, and the membrane surface is not limited to a shallow spherical surface. Of course, a shallow paraboloid is also possible.

Further, for coarse adjustment and fine adjustment of gas pressure supply, it is possible to appropriately preliminarily form a sequence relating to control of pressurizing speed by two or more multi-step switching or stepless switching.

[0054]

As described above, according to the invention of this application, basically, in the expansion / contraction molding by the gas pressure supply to the flexible film surface of the inflatable reflector or the dome on the ground in the artificial satellite, the space station, etc. The film surface data such as the Young's modulus and Poisson's ratio of the surface are input, and the pressure of the forming pressurizing gas is specified according to the displacement amount in the normal direction of the flexible film surface by the above-mentioned formula to form the flexible film surface. Can be controlled in advance or on the way.

Then, when the input of the film surface data and the measurement by the calculation are impossible, the gas supply control is performed only based on the detection information of the detection piece for the position in the normal direction of the flexible film surface and the positioning sensor. Must be done
Therefore, an efficient gas pressurizing sequence cannot be established because the pressurizing speed of the gas and the rate of increase of the center position height cannot be grasped in advance.

According to the invention of this application, the above-mentioned disadvantages of the conventional technology are eliminated, and it is possible to surely perform the pressure molding of the flexible membrane surface as designed, not only in advance but also during the pressing. , The positioning sensor only needs to work precisely in the final fine tuning process, therefore
There is an advantage that the detection range of the precise positioning can be narrowed and the accuracy can be increased, and it is not necessary to repeat the calibration curve frequently.

Of course, the gas pressure necessary for changing the central height of the flexible membrane surface by a predetermined amount prior to the molding of the flexible membrane surface by gas pressure pressing can not only be calculated in advance, but also the pressing process can be performed. It is possible to calculate even in the middle of the process, and it is also possible to calculate and display the pressurization time, and therefore, an excellent effect that a program for the consumption amount of the used gas can be preset can be obtained.

Although the plane system can be adopted, the range of the measurement distance of the sensor can be shortened because the deformation amount of the center point is small in the case of the spherical shape of the flexible film surface.

Further, by forming the flexible membrane surface into a spherical shape, the deformation amount is small, so that the volume change can be suppressed and the internal space can be effectively used.

Furthermore, there is a merit that a part of the flexible film surface can be used as a film body portion for pressure measurement by forming the flexible film surface into a large membrane dome or the like.

[Brief description of drawings]

FIG. 1 is an overall schematic side view of an embodiment of the invention of this application.

FIG. 2 is a schematic diagram of a principle mode.

[Explanation of symbols]

 1'Edge of membrane surface 2 Support structure 5'Rough adjustment feed pipe 5 '' Fine adjustment feed pipe 1 Membrane surface 9 Pressure control device 3 Detection piece 4 Positioning sensor 13 Pressure measurement sensor 10 Display device

Claims (8)

(57) [Claims] 1. A method for fixing a rim of a film surface to a support structure in a sealed state, applying a gas pressure between the support structure and the film surface to press the film surface to form a predetermined shape, The amount of displacement in the normal direction of the film surface is detected, and the pressure is measured by a predetermined calculation using the equilibrium condition of the potential energy of the film from the data and the film surface data obtained in advance, and based on the measured pressure. A method for pressure-molding a flexible film surface, characterized in that the film surface is deformed under pressure while controlling the pressure. 2. The pressure molding method for a flexible film surface according to claim 1, wherein the film surface data includes Young's modulus and Poisson's ratio of the film. 3. The pressure molding method for a flexible film surface according to claim 1, wherein the pressure control is performed by a rough adjustment in a first stage and a fine adjustment in a second stage. 4. The method of pressure molding a flexible film surface according to claim 1, wherein the shape of the film surface before deformation is a spherical shape. 5. The predetermined calculation is as follows: w / a = w _c / a (1-x ⁿ ) v / a = x (1-x) (c ₁ + c ₂ x) x = r / a [Formula 2] f ₁ [(R / a · w _c / a) ⁻¹ , n, ν] = 0 [Formula 3] Pa / Et = (w _c / a) ³ f ₂ [(R / a · w _c / a) ^-1 , n, ν] where P: pressure a: distance from the end z-axis w _c : center point displacement (z direction) w: normal direction displacement ν: Poisson's ratio v: tangential direction Displacement n: Change parameter r: Distance from z-axis c ₁ : Change parameter c ₂ : Change parameter R: Spherical curvature radius (before deformation) E: Young's modulus of film f ₁ , f ₂ : Determined from equilibrium condition [R / a ・ w _c / a]
A quadratic expression for ^-1 t: film thickness, The method for pressure molding a flexible film surface according to claim 1, wherein 6. An apparatus for molding a film surface by fixing the edge of the film surface to a support structure in a sealed state and applying a gas pressure between the support structure and the film surface to press the film surface. A supporting structure for fixing the seal in a sealed state is connected to a pressure control device having a pressure sensor and a pipe for gas supply control, and the pressure control device faces a detection piece provided at a predetermined portion of the film surface. A pressure molding device for a flexible film surface, characterized in that a facing positioning sensor is connected. 7. The pressure molding device for a flexible film surface according to claim 6, wherein the gas supply control pipe is composed of a rough adjustment pipe and a fine adjustment pipe. 8. The pressure control device has a pressure measuring mechanism,
The pressure molding device for a flexible film surface according to claim 6, which is equipped with a display device.