JP2016169830A - Vibration-proof structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-reliable vibration-proof structure for the space.SOLUTION: A vibration-proof structure of this invention includes a direct advance member having a first component directly or indirectly connected to a vibration generating device, a second component directly or indirectly connected to a vibration receiving device and configured in non-symmetrical form in respect to an axis center, and a resilient member connected between the first component and the second component arranged symmetrically in respect to the axis center to connect between the first component and the second component and deformed as the first component and the second component are relatively moved in an axial direction.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a vibration damping structure.

  In recent years, scientific observation satellites and earth observation satellites are equipped with large actuators to perform complex and high-speed attitude control in orbit. This actuator is generally composed of a motor and a speed reducer, and vibration is generated by driving the motor. Since this vibration propagates through the structural part of the satellite and vibrates the installed observation equipment, the performance of the observation equipment deteriorates, so this vibration is called disturbance vibration for the equipment.

  Thus, as a solution to this problem, it has been proposed to incorporate a support mechanism having a damping function in the same manner as, for example, a suspension mechanism used in an automobile to reduce vibration. Since this method uses relative displacement at both ends of the support mechanism, it is necessary to couple the actuator as a disturbance source and its support structure with a weak support rigidity.

  As an example of the suspension mechanism, in the support mechanism 5 shown in FIG. 11, members that move relative to each other are fixed by rotatable hinges 51 a and 51 b, and a spring 52 for adjusting the natural frequency of the system and returning to the origin is interposed between the members. , And a dashpot for damping is fixed. The dashpot includes a cylinder 53 and a piston 54, and the piston 54 is provided with an orifice 55. The damping force is a viscous resistance force of the oil 56 that passes through the piston 54 when the piston 54 moves. Further, the dashpot is provided with sliding bearings 57 and 58 that also function as an oil seal for maintaining a straight movement between the cylinder 53 and the piston 54.

  As in Patent Document 1 and Non-Patent Document 1, it is conceivable to construct a parallel link mechanism having a total of 6 degrees of freedom of three translational axes and three rotational axes by combining six linear motion mechanisms as support mechanisms. . In this mechanism, the degree of freedom of rotation is also achieved by a combination of linear movements, and it is necessary to incorporate at least six devices having a damping function for linear movements.

  In each of the linear motion mechanisms, a spring and a dashpot having a predetermined rigidity are incorporated as in Patent Document 2, for example. The spring stiffness is determined by the elastic modulus and shape of the support member, and the damping coefficient is determined by the viscosity characteristics of the oil sealed inside and the orifice diameter inside the apparatus. Moreover, there exists an example of the rectilinear mechanism supported by the parallel leaf | plate spring like patent document 3. FIG.

  Patent Document 4 discloses a damping alloy member, a floor vibration damping device and the like having a function of mitigating vibration and noise. This floor vibration damping device using a damping alloy member uses a spring-like damping alloy member and combines a spring structure with a plurality of springs having different spring constants in the height direction. Damping with a spring. In addition, the spring having a low spring constant is configured to be in close contact with the lid and to be damped by the spring having a high spring constant at a high load.

JP 2010-264526 A JP 2002-323083 A JP2013-022666A JP-A-2005-121207

Ogura et al., "Method of calculating the dynamics of a Stewart platform type parallel link manipulator", Transactions of the Japan Society of Mechanical Engineers (C), Vol. 60, No. 569, pp218-224

  However, these Patent Documents 1 to 4 and Non-Patent Document 1 have the following problems, and there is a difficulty in selecting them as a vibration damping structure for space. First, in Patent Documents 1 and 2 and Non-Patent Document 1, since the damping device is a pressure vessel filled with oil, it is necessary to verify reliability of oil leakage and strength, and guarantee of safety. It is necessary to stack several times. Moreover, since oil is generally a polymer material, consideration must be given to prevent deterioration of attenuation performance against a vacuum environment or a radiation environment. Furthermore, there are sliding parts of pistons and cylinders, and it is difficult to evaluate the reliability against frictional fluctuations and wear.

  In patent document 3, there exists a difficulty which has the nonlinearity from which the deformation | transformation resistance of the tensile force generation with respect to contracting to a length direction when a leaf | plate spring deform | transforms becomes large. Although there is a support structure that employs a damping alloy having a large internal friction as a damping material as in Patent Document 4, this structure deforms in various directions and cannot be incorporated into a linear motion mechanism.

  An object of the present invention has been made in view of the above problems, and is to provide a vibration damping structure that solves the above problems.

  In view of the above-described problems, one embodiment of the present invention includes a first component that is directly or indirectly connected to the vibration generator and a second component that is directly or indirectly connected to the vibration receiver. A linear motion member configured asymmetrically with respect to the shaft center, and symmetrically disposed with respect to the shaft center and connected between the first component and the second component, the axial direction The present invention relates to a vibration damping structure comprising: an elastic member that deforms with relative movement of the first part and the second part.

  According to the present invention, it is possible to provide a highly reliable vibration damping structure that can obtain a damping effect.

  Further advantages and embodiments of the present invention are described in detail below using the description and the drawings.

It is a schematic block diagram which shows the outline of the artificial satellite to which the damping structure by the 1st Embodiment of this invention is applied. It is a side view which shows the structure of the rectilinear motion member in the damping structure shown in FIG. FIG. 3 is a three-dimensional view illustrating a schematic configuration of the rectilinear motion member illustrated in FIG. 2. It is a figure for demonstrating operation | movement of the rectilinear motion member shown in FIG. (A) And (b) is a figure which shows the example of the leaf | plate spring used for the rectilinear motion member in the damping structure by the 2nd Embodiment of this invention. It is a figure for demonstrating the stress distribution of the flat spring utilized with the damping structure by the 1st Embodiment of this invention. It is a figure for demonstrating the stress distribution of the flat spring utilized with the damping structure by the 2nd Embodiment of this invention. It is a figure for demonstrating the stress distribution of the flat spring utilized with the damping structure by the 2nd Embodiment of this invention. It is a side view which shows the structure of the rectilinear motion member in the related damping structure. It is the elements on larger scale for demonstrating operation | movement of the rectilinearly-moving member shown in FIG. It is a side view which shows the structure of the support mechanism in a related damping structure.

  First, a technique studied by the present inventor and problems thereof will be described with reference to FIGS. 9 and 10. FIG. 9 is a diagram showing a configuration of the rectilinear motion member 4 in the related vibration control structure. FIG. 10 is a view for explaining the operation of the rectilinear motion member 4 shown in FIG.

  Referring to FIG. 9, there is illustrated a rectilinear motion member 4 that does not use the dashpot used in the support mechanism of FIG. 11 and does not have a sliding bearing for rectilinear motion. In the linearly moving member 4, flat springs 44a, 44b, 44c, and 42d are incorporated between a cylinder 42a and a piston 42b that move relative to each other.

  If the flat springs 44a to 44d are made of a damping alloy, the linear motion function and the damping function can be achieved simultaneously. However, in such a symmetrical arrangement with respect to the axis 45 of the both end support points, when the flat springs 44a to 44d are deformed, a contraction 46 due to the deformation of the flat springs 44a to 44d occurs as shown in FIG. There is a difficulty with non-linearity that increases the deformation resistance of the generation of tensile force against shrinking in the vertical direction. Further, since the tensile force is generated, the tensile stress is superimposed on the bending stress generated by the bending deformation, and there is a difficulty in that the strength at the same deformation amount is lowered.

  Embodiments of the present invention that can solve the above-described problems will be described with reference to the drawings. However, needless to say, the following description does not limit the technical scope of the present invention.

(First embodiment)
First, a first embodiment of the present invention will be described.

  FIG. 1 shows an example in which the vibration damping structure according to the first embodiment is incorporated between the artificial satellite body 1 and the observation device 3. As a vibration control structure, one end of a plurality of rectilinear motion members 2a to 2f is fixed to the artificial satellite body 1, and an observation device 3 is supported on the other end of the plurality of rectilinear motion members 2a to 2f to constitute a parallel mechanism 2. . The artificial satellite body 1 is equipped with an artificial satellite-mounted actuator 1a such as a solar battery paddle driving unit. When this artificial satellite mounted actuator 1a is driven, vibration is generated. In this embodiment, the linear motion members 2 a to 2 f constituting the parallel mechanism 2 suppress the transmission of external vibrations that cause disturbance vibration to the observation device 3 to the observation device 3.

  Examples of the observation device 3 include an optical system for an astronomical observation satellite such as a high-resolution telescope, an optical system for an earth observation satellite such as a low-light astronomical spectroscopic imaging device, a high dispersion spectrometer, and an optical microscope. It is not limited.

  FIG. 2 is a side view showing the configuration of the rectilinear motion member 2a in the vibration damping structure according to the first embodiment of the present invention. FIG. 3 shows a schematic configuration of the rectilinear motion member 2a shown in FIG. FIG. 4 is a view for explaining the operation of the rectilinear motion member 2a shown in FIG. Each of the linear motion members 2a to 2f constituting the parallel mechanism 2 is for suppressing vibration transmitted to the observation device 3 mounted on the satellite main body 1. Here, the configuration of these rectilinear motion members 2a to 2f will be specifically described taking the rectilinear motion member 2a as an example. In the description of the present specification, the rectilinear motion member 2a may be described as a member having a first component and a second component, and may be described as a member including flat springs 24a and 24b. There is also.

  2 and 3, the vibration damping structure of the present embodiment includes a linear motion member 2a having a first part and a second part, and flat springs (leaf springs) 24a and 24b. The first part includes a connecting portion 21a connected to the satellite body (vibration generating device) 1 or the observation device (vibration receiving device) 3, a flat plate spring 24a extending from one end of the connecting portion 21a in the axial direction (X direction), a flat spring support 22a connected to b. The second part includes a connecting portion 21b connected to the satellite body 1 or the observation device 3, and a flat spring support extending from one end of the connecting portion 21b in the axial direction (X direction) and connected to the flat springs 24a and 24b. Part 22b. The flat springs 24a and 24b are arranged symmetrically with respect to the axis 30 and connect between the first part and the second part, and with the relative movement of the first part and the second part in the axial direction. Deform.

  Flat spring support portions 22a and 22b are provided only on one side from the support points at both ends of the rectilinear motion member 2a so as to be asymmetric with respect to the axis 30. This structure is characterized in that the force when the flat springs 24a and 24b are deformed and contracted in the length direction is released by the rotation of both end support points so as not to cause deformation resistance.

  The flat springs 24a and 24b are made of, for example, a damping alloy material, and are deformed in accordance with the movement of the linear motion member 2a in the axial direction or the vibration of the artificial satellite mounting actuator 1a mounted on the artificial satellite body 1. In the illustrated example, two flat springs 24a and 24b are connected between the flat spring support 22a and the flat spring support 22b in parallel with the Z direction. However, the present invention is not limited to this example and is to be realized. In connection with the design of the structure, three or four or more flat springs may be connected to achieve a desired damping effect.

  In addition, the first part and the second part are described separately for each part of the connecting parts 21a and 21b and the flat spring support parts 22a and 22b for convenience, but they are manufactured separately rather than separately. You may use things.

  As shown in FIG. 4, when the second part connected to the satellite body 1 receives vibration from the satellite-mounted actuator 1a, the connecting portion 21b and the flat spring support portion 22b are vibrated. This vibration prevents the flat springs 24a and 24b, which are elastic members, from acting as a damping material and being transmitted to the first component. As a result, the observation device 3 connected to the first component is affected by the vibration. Can be prevented.

  The shape of the flat springs 24a and 24b, such as the material, plate thickness, width, and length, is determined by evaluating the natural frequency and strength, and it is evaluated that the damping alloy material generates the necessary damping force. It is determined.

  The first embodiment of the present invention described above has the following effects.

  The first effect is that a damping effect is obtained with a highly reliable structure as compared with a vibration damping mechanism related to oil leakage, radiation deterioration, or frictional wear. The reason is that the vibration damping mechanism according to the present embodiment uses a support mechanism using a flat spring to constitute a linear motion mechanism that does not use oil and has no sliding portion.

  The second effect is that a high damping function is provided to reduce the size of the vibration damping structure while preventing transmission of disturbance vibration to the mounted device. The reason is that the stress generated by making the arrangement of the linearly moving member asymmetric with respect to the axial center of the both end support points is reduced.

(Second Embodiment)
Subsequently, a second embodiment of the present invention will be described. The second embodiment of the present invention is a modification of the above-described first embodiment. Hereinafter, in the present embodiment, parts having the same functions as those already described in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  FIGS. 5A and 5B show a flat spring (leaf spring) 24a used in the vibration damping structure according to the second embodiment of the present invention. 6 to 8 are views for explaining the relationship between the deformation of the flat spring 24a used in each embodiment and the stress distribution.

  Referring to FIG. 6, the stress distribution and its deformation state when the plate spring 24a has a uniform thickness are shown. When the plate thickness of the flat spring 24a is uniform, the stress distribution is linearly distributed in the length direction, and stress applied particularly to the end portion concentrates on the deformation of the flat spring 24a due to vibration or the like. When the stress is concentrated on a part, the damping performance of the flat spring 24a may be affected. Therefore, the flat spring 24a shown below is employed in the present embodiment.

  FIG. 7 is a diagram showing the deformation and stress distribution of the flat spring 24a shown in FIG. When the end portion of the flat spring 24a is thick and the central portion is thin, the stress applied to the end portion can be reduced, and the flat plate spring 24a becomes sturdy. Therefore, the damping performance of the rectilinear motion member 2a in the damping structure can be improved by using the flat spring 24a having excellent damping performance. Moreover, since the wide range distortion of the flat spring 24a can be increased, the damping performance can be improved.

  FIG. 8 is a diagram showing the deformation and stress distribution of the flat spring 24a shown in FIG. The flat spring 24a shown in FIG. 8 has a wide end portion and a narrow central portion instead of adjusting the plate thickness. In this case as well, the stress applied to the end portion can be reduced, and the sturdy flat spring 24a can be reduced. It becomes. Therefore, the damping performance of the rectilinear motion member 2a in the damping structure can be improved by using the flat spring 24a having excellent damping performance. Moreover, since the wide range distortion of the flat spring 24a can be increased, the damping performance can be improved.

  Further, since the vibration damping performance depends on the strain generated in the flat spring 24a, relative movement is achieved by reducing the thickness distribution at the center or narrowing the width distribution at the center as shown in FIGS. Sometimes the stress generated in the flat spring 24a, that is, the strain, can be equalized. As a result, the damping performance can be increased as compared with the case where the plate thickness is uniform and the strain is concentrated at the end. The shape, such as the material, plate thickness, width, and length, of the flat spring 24a is determined by evaluating the natural frequency and strength, and the damping alloy material is determined by generating the necessary damping force.

  In the second embodiment of the present invention described above, the following effects are obtained in addition to the first and second effects obtained in the first embodiment.

  The third effect is that the structure is robust and a high damping function can be realized. The reason is that in the vibration damping mechanism according to the present embodiment, the arrangement of the linearly moving member is asymmetric with respect to the axial center of the both end support points, and the shape of the flat spring is made thin or narrow at the center. is there.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

DESCRIPTION OF SYMBOLS 1 Artificial satellite main body 1a Artificial-satellite mounted actuator 2 Parallel mechanism 2a-f Linear motion member 21a, b Hinge (connection part)
22a, b Flat spring support 24a, b Flat spring (elastic member)
3 Observation equipment 30 axis

Claims (8)

A first part that is directly or indirectly connected to the vibration generator and a second part that is directly or indirectly connected to the vibration receiver, and is asymmetric with respect to the axis. A rectilinear motion member configured;
Elasticity arranged symmetrically with respect to the axis and connecting between the first part and the second part, and deforming with relative movement of the first part and the second part in the axial direction A vibration control structure comprising: a member;   2. The vibration damping structure according to claim 1, wherein the elastic member is two or more leaf springs respectively disposed on two or more planes orthogonal to the axial direction.   The damping structure according to claim 1 or 2, wherein the leaf spring has a thickness at a central portion smaller than that of an end portion.   3. The vibration damping structure according to claim 1, wherein the leaf spring has a width at a center portion smaller than that of an end portion.   The damping structure according to any one of claims 2 to 4, wherein the leaf spring is made of a damping alloy material.   The first component and the second component are connected to the vibration generating device or the vibration receiving device, and are connected to the leaf spring extending in an axial direction from one end of the first component and the second component. A vibration damping structure according to any one of claims 2 to 5, further comprising a leaf spring support portion.   The first component is connected to a satellite body, and the second component is the linear motion member connected to an observation device, and the linear motion member is mounted in combination to form a parallel mechanism. The vibration damping structure according to any one of claims 1 to 6, wherein the vibration damping structure is characterized in that:   An artificial satellite having the vibration damping structure according to any one of claims 1 to 7.

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