JP2015040889A - Reflective mirror - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reflective plate which uses a reflective material with a metallic sheet, such as a metallic foil, as a base material and has good flatness.SOLUTION: A mirror 10, other than weight sections 12, is positioned without being in contact with a mounting frame 20 (a long side frame 21, a short side frame 22), and is fitted in the mounting frame 20 with initial tension introduced thereon using at least one of weight on the weight sections 12, push-up force of tension exerting members 31, and joining bolts/nuts 24.

Description

  The present invention relates to a reflecting plate, and more particularly to a reflecting plate that uses a sheet-like metal (metal sheet) as a base material and smoothes the reflecting surface by tension.

  In power generation applications using sunlight or solar heat, there is a technology for improving efficiency by collecting and collecting heat with a reflector. In the power generation application, a large glass mirror is generally used as the reflector, but there are problems due to the characteristics of the glass, such as the glass mirror being heavy and being easily broken.

  On the other hand, as an alternative to glass mirrors, metal plates, aluminum resin composite plates, resin films, etc. with a surface reflectance of 80% or more have been studied and put to practical use. It is necessary to take measures against external forces such as distortion and wind load.

  On the other hand, Patent Document 1 proposes a reflector that is lightweight and accurate and a manufacturing method thereof.

  The reflecting mirror described in Patent Document 1 uses a film mirror in which a metal thin film having a high reflectance such as Al or Ag is coated on the surface of a plastic film by vapor deposition or sputtering. When the film mirror is fixed to a rectangular or circular metal frame, the tensioned state is maintained. As a method of applying tension to the film mirror, after fixing the periphery of the film mirror with a jig, the metal frame is pressed against the film mirror surface, and the tension is applied to the film mirror by means such as adhesion. A method of fixing to the frame or a method of using two metal frames, attaching a film mirror to the outer metal frame, and forcibly pushing up the film mirror surface with the inner metal frame to apply tension. I have to.

  In this way, since tension is applied to the film mirror, a reflective surface with good plane accuracy can be obtained, and the basic structure is made up of only the film mirror and metal frame, so the weight is very light and reflective. It is stated that the larger the mirror size, the more advantageous it becomes.

JP-A-9-61608

  However, the technique described in Patent Document 1 has a problem in terms of strength and durability in terms of outdoor use since the base material of the reflective material is a plastic film, and is used as a reflector for solar heat utilization. Have difficulty.

  Therefore, it is conceivable to use a sheet-like metal (metal sheet) such as a metal foil, which has good strength and durability, instead of the plastic film as the base material of the reflective material. Since it is remarkably small as compared with the film, the following problems arise when trying to ensure the flatness of the reflecting surface by the method described in Patent Document 1.

  That is, if the metal sheet is fixed around a frame that cannot ensure complete flatness, distortion and wrinkles are generated in various portions of the metal sheet, and it is rather difficult to ensure flatness. In addition, in the attachment of the reflective material to the frame in the stage before forcibly introducing the tension, there is no particular problem with the flexible and flexible plastic film, but the metal sheet is easily plastically deformed when bent, Once the crease is attached, it cannot be repaired.

  As described above, since the metal sheet is greatly different in characteristics from the plastic film, a new measure is required for its handling.

  In addition, for example, a countermeasure on the support structure side when a much larger tension is introduced compared to a plastic film against bending and twisting when the length is increased to 2 m or more, that is, a reaction of a large introduction tension. New measures to reduce accuracy due to force are also necessary.

  The present invention has been made in view of the circumstances as described above, and provides a reflector having good flatness using a reflector made of a metal sheet such as a metal foil as a base material. It is intended.

  In order to reduce the weight of the reflector and reduce the cost, when a film-like thin film is used as the reflector, the thickness of the reflector is extremely thin, so that it is greatly bent by its own weight and it is difficult to ensure flatness. In particular, when the size is increased, the tendency is further increased. Therefore, we want to ensure the flatness of the reflective material by introducing tension, but in that case, in order to counteract its own weight and external force (wind load etc.), it is necessary to increase the introduced tension, It is necessary to use a reflector made of a strong metal sheet (such as a metal foil) as a base material, and to prevent a failure caused by a reaction force.

  In addition, a metal sheet (metal foil or the like) is bent in an arbitrary direction by its own weight, easily plastically deforms and has a crease, and cannot be repaired. Therefore, it is necessary to take measures for attachment to the frame.

  Therefore, the present invention has the following features.

[1] A reflector having a rectangular metal sheet as a base material, and a pair of weight portions to which plate-like bodies are attached over substantially the entire length of both ends of the short side or both ends of the long side of the reflector. Mirror and
It has a short side frame or a long side frame corresponding to the short side or the long side of the reflector to which the plate-like body is attached, and the weight portion is joined to the upper surface or the side surface of the short side frame or the long side frame. A mounting frame having a flat surface portion to be attached using a nut and serving as a mirror mounting portion;
It is arranged on the inner side or the upper surface of the mirror mounting part, and is movable up and down, and the movement of the mounting frame is restricted to the inner side. A pair of tensioning members;
A screw portion provided at a predetermined interval in the length direction of the frame on the side having the mirror mounting portion, and an adjustment bolt disposed on the female screw portion with the screw tip side facing upward; A tension applying member supporting portion for supporting the additional member,
The mirror is disposed in a non-contact state with respect to the mounting frame at a portion other than the weight portion, and at least one of the weight of the weight portion, the lifting force of the tension applying member, and the joining bolt nut. The reflector is attached to the mounting frame in a state in which an initial tension is introduced using the reflector.

  [2] From the state in which the initial tension is introduced and the mirror is attached to the mounting frame, the mirror is further tightened with the adjusting bolt and the tension applying member is moved upward to introduce additional tension. The reflecting plate according to [1], wherein the flat surface of the mirror is held.

  [3] The protruding length of the adjusting bolt at the intermediate portion in the longitudinal direction of the tension applying member supporting portion is set to be equal to or longer than the protruding length of the adjusting bolt at the longitudinal end portion of the tension applying member supporting portion. The reflector according to [1] or [2].

[4] A length of the adjustment bolt is longer than a cross-sectional height of the tension applying member.
The tension applying member is an open cross-section member or a closed cross-section member having an upper surface and a lower surface, and a through hole is provided on the lower surface at a position corresponding to the adjustment bolt of the tension applying member support portion. The adjustment bolt is inserted, the tip of the adjustment bolt is internally provided in the cross section of the tension applying member, and the tip of the adjustment bolt is brought into contact with the back side of the upper surface of the tension adding member. [1] The reflector according to any one of [3].

  [5] A connecting member for connecting the frames on the side having the mirror mounting portion to each other at an intermediate portion in the length direction is disposed, and at this time, the interval between the connecting members on the length side central portion side is set to be long. The reflector according to any one of [1] to [4], wherein the distance is equal to or less than the distance on the side in the longitudinal direction.

  [6] The reflector according to any one of [1] to [5], wherein an initial height position of the upper surface of the tension applying member is set to a height position higher than the upper surface of the mounting frame. .

  [7] The reflector according to any one of [1] to [6], wherein the tension applying member is attached to an upper surface of the attachment frame.

  [8] It has a rotation axis at a height position higher than the upper surface of the mounting frame at a center position in the length direction of the short side frame, and at substantially the same height position as the reflection surface of the mirror. The reflector according to any one of [1] to [7].

  [9] Any of the above [1] to [8], wherein the base material of the reflective material is a steel material, and a reflective film having a surface roughness Ra ≦ 0.015 μm is provided on the surface of the base material. The reflector as described in.

  In the present invention, a reflector having a good flatness can be obtained by using a reflector having a metal sheet such as a metal foil as a base material.

  That is, the reflector according to the present invention causes a mirror using a reflector made of a metal sheet such as a metal foil to cause plastic deformation on the mounting frame in a state where initial tension is introduced in one direction. Even if it is a mirror using a metal sheet, it is possible to ensure a flat surface regardless of the accuracy and deformation of the mounting frame. And since the additional tension can be introduced in the same direction as the introduced tension by the tension applying member and the adjusting bolt, even in the tension fluctuation based on the material length change due to thermal expansion and contraction or external force (wind load etc.), especially in the external environment, The plane of the mirror can be stably held.

It is a top view of the reflecting plate concerning Embodiments 1-3. It is a figure (AA sectional drawing of FIG. 1) which shows the mirror attachment state in Embodiment 1. FIG. It is a figure (AA sectional drawing of FIG. 1) which shows the tension | tensile_strength addition state in Embodiment 1. FIG. It is a figure (AA sectional drawing of FIG. 1) which shows the state before the mirror attachment in Embodiment 2. FIG. It is a figure (AA sectional drawing of FIG. 1) which shows the state after the mirror attachment in Embodiment 2. FIG. It is a figure (AA sectional drawing of FIG. 1) which shows the state which attached one weight part in Embodiment 3. FIG. It is a figure (AA sectional drawing of FIG. 1) which shows the state which attached both the weight parts in Embodiment 3. FIG. 6 is a plan view of a reflector according to Embodiment 4. FIG. It is a figure (AA sectional drawing of FIG. 8) which shows the state during mirror attachment in Embodiment 4. It is a figure (AA sectional drawing of FIG. 8) which shows the state after the mirror attachment in Embodiment 4. 10 is a drawing-substituting photograph showing a reflector in Example 2. FIG.

  Embodiments (Embodiments 1 to 4) of the present invention will be described with reference to the drawings.

[Embodiment 1]
Embodiment 1 of the present invention will be described.

  FIG. 1 is a plan view showing a reflector according to Embodiment 1 of the present invention, and FIG. 2 is a view showing a mirror mounting state in Embodiment 1 (cross-sectional view taken along line AA in FIG. 1). These are the figures (AA sectional drawing of FIG. 1) which show the tension | tensile_strength addition state in this Embodiment 1. FIG.

(1) Mirror The mirror 10 of the reflector 1 uses a reflector 11 made of a rectangular metal sheet (here, a thin steel plate) as a base material. The strength and plate thickness of the substrate may be selected according to the use environment, but a foil or film with a tensile strength of 270 to 490 Mpa and a plate thickness of about 0.05 mm to about 0.3 mm is suitable. is there.

  In addition, the base material of the reflecting material 11 can be arbitrarily set in consideration of the size of the reflecting plate and each member even if the strength and thickness are out of the above range. More specifically, there is no problem even if the thickness is 0.3 mm or more as long as the thickness is flexible between the pair of tension applying members 31. For example, the thickness is about 4.5 mm or more. There may be.

  The surface of the reflective material 11 is preferably a structure having a reflective film having a surface roughness Ra ≦ 0.015 μm. In order to increase the corrosion resistance, a film-like protective film is formed on the back surface of the substrate. It is desirable to have Furthermore, the reflective film on the front surface and the protective film on the back surface are extended beyond the width or length of the base material so as to be overlapped and adhered, or by separately providing an end surface cover, at least on the mounting frame 20. It is more preferable that the end face on the non-fixed side (here, the end face on the short side frame 22 side) has a structure in which the end face of the base material is not exposed.

  Furthermore, it is more desirable to have a protective film made of Si and Al having a surface roughness Ra ≦ 0.015 μm on the surface of the reflective film, the reflective film contains 50% by mass or more of Al and / or Ag, and the base material is A stainless steel plate containing 10 to 35% by mass of Cr is most desirable.

  The mirror 10 has a plate-like body (here, on the front surface or / and the back surface of the reflector 11 over substantially the entire length of both ends on the short side or both ends on the long side (here, both ends on the long side) of the reflector 11. A pair of weight portions 12 each having a plate-like body 12 a on the surface of the reflecting material 11 and a plate-like body 12 b on the back surface of the reflecting material 11 are provided.

  The weight portion 12 (plate-like bodies 12a and 12b) may be made of a steel plate or the like so long as it has a weight capable of introducing the tension to the reflecting material 11 by its own weight. The plate-like body 12a on the reflecting material 11 surface side is the surface of the reflecting material 11 It is better if chamfering processing such as a polygon or a circle is performed on the end portion in contact with the surface.

  More specifically, the weight of the weight part 12 is raised by vertically lifting one of the pair of weight parts 12 so that the outer surfaces of the plate-like bodies 12a and 12b are on the upper side, and the other weight part 12 is a mirror. 10 is a weight capable of maintaining a state in which a vertically downward tension is introduced in parallel with the reflecting surface of the mirror 10 (reflecting material 11) by being positioned at the lower end of the mirror 10, or the mirror between the pair of weight portions 12 The weight is such that a tension can be introduced into the reflecting surface of the mirror 10 (reflecting material 11) by the weight of the weight portion 12 in a state where 10 is supported substantially horizontally.

  The weight portion 12 (plate-like bodies 12a and 12b) is attached to the reflector 11 by adhesion, adhesion, welding, or other mechanical means, and passes through the plate-like body 12a, the reflector 11 and the plate-like body 12b ( Bolt holes) 12c are provided at predetermined intervals to constitute the mirror joint portion 15.

(2) Mounting frame The mounting frame 20 of the mirror 10 is made of a relatively strong material because the metal sheet (in this case, a thin steel plate) used for the base material of the reflector 11 has no rigidity and a high introduction tension. It is necessary to ensure a predetermined strength and rigidity by using an appropriate material such as a steel material or an aluminum extruded material. The width and length can be set arbitrarily.

  The mounting frame 20 of the mirror 10 has a short side frame 22 and a long side frame 21 corresponding to the short side and the long side of the reflective material 11, and the side of the reflective material 11 on the side having the weight portion 12 (here, reflective On the upper surface of a frame corresponding to the long side of the material 11 (here, the long side frame 21), the mirror joining portion 15 (weight portion 12) is attached to have a flat portion that becomes the mirror attaching portion 21a.

  The mirror mounting portion 21a is provided with a through hole (bolt hole) 21b corresponding to the through hole (bolt hole) 12c of the mirror joint portion 15 (weight portion 12).

  The frames (here, the long-side frame 21) having the mirror mounting portion 21a are connected to each other by a connecting member (not shown) at a plurality of positions in the middle portion in the length direction, and the arrangement interval of the connecting members With respect to, the distance of the long side frame 21 on the center side in the length direction is set to be equal to or less than the distance on the end side in the length direction.

(3) Tension applying member On the inner side of the frame having the mirror mounting portion 21a (here, the long side frame 21), the length of the long side frame 21 is substantially the entire length, and the upper surface is made of a curved surface. A tension applying member 31 made of resin only on the upper surface is provided.

  The tension applying member 31 is supported by the tension applying member support portion 33 and is restrained from moving in the inner direction between the long side frames 21 by the restraining portion 34.

  The tension applying member supporting portion 33 is provided at a predetermined interval in the length direction at a position where the planar position thereof is separated from the inner surface of the long side frame 21 by ½ or more of the width of the tension applying member 31. In addition, the internal thread portion 33a includes an adjustment bolt 35 that is disposed with the screw tip side facing upward.

  The tension applying member 31 is an open cross-section member or a closed cross-section member having at least an upper surface and a lower surface, and a lower through hole 31a larger than the diameter of the adjustment bolt 35 is provided on the lower surface at a position corresponding to the arrangement of the adjustment bolt 35. Is provided.

(4) Tension applying member support portion The tension applying member support portion 33 may be provided independently at a predetermined location over the entire length of the tension applying member 31. Furthermore, the cross-sectional shape may be a flat plate shape, but as an angle shape, the open cross-section side may be attached to the inside of the long side frame 21, and in that case, the upright side portion is attached to the side surface of the tension applying member 31. If the movement toward the inner side of the long side frame 21 is restricted, the trouble of adding the restriction part 34 can be omitted.

  The length of the adjusting bolt 35 of the tension applying member support 33 is longer than the cross-sectional height of the tension applying member 31, and the adjusting bolt 35 is inserted and disposed in the lower through hole 31 a of the tension adding member 31. The front end of the adjustment bolt 35 is internally provided in the cross section, and the front end of the adjustment bolt 35 can be brought into contact with the back side of the upper surface of the tension applying member 31.

  When the reflector is used as a plate-like mirror for a linear Fresnel type, a position higher than the upper surface of the mounting frame 20 at the center position in the length direction of the short side portion (short side frame 22) of the mounting frame 20 In addition, the rotating shaft 39 is provided at a position substantially the same height as the reflecting surface of the mirror 10.

  The procedure for attaching the mirror and introducing the tension (initial tension introduction, additional tension introduction) in Embodiment 1 will be described in Example 1 described later.

[Embodiment 2]
A second embodiment of the present invention will be described. In addition, about the same part as Embodiment 1 of said this invention, description here is abbreviate | omitted.

  4 is a diagram (a cross-sectional view taken along the line AA in FIG. 1) before the mirror is mounted in the second embodiment, and FIG. 5 is a diagram (FIG. 1) illustrating the state after the mirror is mounted in the second embodiment. It is AA sectional drawing. 4 and 5, the restraining portion 34 is not shown.

  In the second embodiment, the mirror mounting and the initial tension introduction are performed simultaneously in the first embodiment.

  The initial height position of the upper surface of the tension applying member 31 is set to be equal to or higher than the height position of the upper surface of the long side frame 21 (the upper surface of the mirror mounting portion 21a), and in particular, the plate-like body 12b on the back surface of the reflector 11 in the weight portion 12. Is set to a height position equal to or higher than the height position of the upper surface of the long side frame 21 plus the plate thickness of the plate-like body 12b.

  At this time, the distance between the fulcrums of the mirror joint 15 (the distance between the through holes 12c in the length direction of the short side frame 22) is the distance between the fulcrums of the mirror mounting portion 21a (the length of the through hole 21b in the length direction of the short side frame 22). By fastening the mirror joint portion 15 and the mirror attachment portion 21a to the same dimension as the interval), the attachment of the mirror 10 and the introduction of the initial tension can be performed simultaneously.

  Since any additional tension can be introduced by tightening the adjustment bolt 35 later, the distance between the fulcrums of the mirror joint 15 and the initial height position of the upper surface of the tension applying member 31 are determined in consideration of the necessary initial tension. Just decide.

  An additional description of the second embodiment will be given in a second example described later.

[Embodiment 3]
Embodiment 3 of the present invention will be described. In addition, description here is abbreviate | omitted about the same part as said Embodiment 1, 2 of this invention.

  FIG. 6 is a diagram (a cross-sectional view taken along the line AA of FIG. 1) in which one weight portion is attached in the third embodiment, and FIG. 7 shows a state in which both weight portions are attached in the third embodiment. It is a figure (AA sectional drawing of FIG. 1) shown. 6 and 7, the short side frame 22 and the restraining portion 34 are not shown.

  In the third embodiment, the initial height position of the tension applying member 31 is further increased in the second embodiment, and the initial height position of the lower surface of the tension applying member 31 is set to the upper surface of the long side frame 21 (mirror mounting portion 21a). The height of the upper surface).

  An additional description of Embodiment 3 will be given in Example 3 to be described later.

[Embodiment 4]
Embodiment 4 of the present invention will be described. In addition, description here is abbreviate | omitted about the same part as said Embodiment 1-3 of this invention.

  FIG. 8 is a plan view showing a reflector plate according to Embodiment 4 of the present invention, and FIG. 9 is a diagram (a cross-sectional view taken along line AA in FIG. 8) showing a state during mirror mounting in Embodiment 4. FIG. 10 is a diagram (a cross-sectional view taken along the line AA in FIG. 8) illustrating a state after the mirror is attached in the fourth embodiment. 9 and 10, the short side frame 22 and the restraining portion 34 are not shown.

  In the fourth embodiment, the mirror attachment portion 21a is provided on the side surface of the attachment frame 20 (here, the long side frame 21).

  In this case, the tension applying member 31 may be attached to the upper surface of the long side frame 21, whereby the long side frame 21 also serves as the tension applying member support portion 33. More desirably, the outermost edge of the tension applying member 31 is set to a position equal to or larger than the width of the long side frame 21.

  That is, the mirror 10 is arranged on the tension applying member 31 arranged in parallel with the long side frame 21 with the weight portion 12 parallel to the long side frame 21, and in the arrangement state, the mirror is weighted by the weight of the weight portion 12. The initial tension is introduced into the mirror 10, and the mirror 10 (weight portion 12) is fixed to the mirror mounting portion 21a by mechanical means (here, the joining bolt nut 24: the joining bolt 24a and the joining nut 24b).

  Here, the dimension of the mirror 10 is a dimension in which the through hole 12c of the weight part 12 and the through hole 21b of the mirror mounting part 21a coincide with each other in a side view of the arrangement state. By setting the outermost edge position to a position equal to or larger than the width of the long side frame 21, the tension that can be introduced when the joining bolt nut 24 is fastened can be increased as the width is increased.

  In this case, it is preferable that at least the outermost edge of the tension applying member 31 does not support the mirror 10 at an acute angle, and a circular steel pipe or the like is used for the tension applying member 31 so as to support it in an arc shape. And better.

  An additional description of the fourth embodiment will be given in a later-described example 4.

  As described above, in the present invention, a reflector having good flatness can be obtained using a reflector made of a metal sheet such as a metal foil as a base material.

  That is, the reflector according to the present invention causes a mirror using a reflector made of a metal sheet such as a metal foil to cause plastic deformation on the mounting frame in a state where initial tension is introduced in one direction. Even if it is a mirror using a metal sheet, it is possible to ensure a flat surface regardless of the accuracy and deformation of the mounting frame. And since the additional tension can be introduced in the same direction as the introduced tension by the tension applying member and the adjusting bolt, even in the tension fluctuation based on the material length change due to thermal expansion and contraction or external force (wind load etc.), especially in the external environment, The plane of the mirror can be stably held.

  Further, since the movement of the tension applying member toward the inner side of the mounting frame is restricted, the stress acting on the tension applying member as the tension increases, that is, the tilt of the tension applying member toward the inner side of the frame is attempted to move. It is possible to counteract the stress to be applied, suppress the decrease in the effect of the tension applying member, and ensure the accuracy of the mirror plane and effective width.

  Further, if the protruding length of the adjusting bolt at the intermediate portion is set to be longer than the protruding length of the adjusting bolt at the end portion and the tension applying member is moved upward, the entire deflection in the longitudinal direction of the mounting frame caused by the reaction force of its own weight and introduced tension The linearity of the tension applying member can be maintained without following the (convex shape downward), and the plane of the mirror can be easily held even when the length is increased.

  Furthermore, the length of the adjusting bolt is longer than the cross-sectional height of the tension applying member, and the tension adding member is provided with a through hole at a position corresponding to the adjusting bolt of the tension adding member support portion on the lower surface thereof. If the adjustment bolt is inserted into the through hole, the tip of the adjustment bolt is housed in the cross section of the tension applying member, and the tip of the adjustment bolt is brought into contact with the back side of the upper surface of the tension applying member, It is possible to improve the stability by improving the stability with respect to the movement in the direction and the restraint force to the movement in the lateral direction, and improve the accuracy, and at the contact portion between the upper surface of the tension applying member and the back surface of the mirror, stress concentration, plastic deformation and damage to the mirror Can reduce the risk.

  Further, a connecting member for connecting the frames on the side having the mirror mounting portion to each other at an intermediate portion in the length direction is disposed, and at this time, the interval between the connecting members on the length direction central portion side is set in the length direction. If the distance is equal to or less than the distance on the end side, the rigidity on the central side in the length direction is increased with respect to the stress that causes drum-like deformation in plan view, which occurs when tension is introduced in one direction of the metal sheet. It is possible to ensure the shape accuracy of the entire metal sheet by making it higher than the direction end portion side.

  Furthermore, if the initial height position of the upper surface of the tension applying member is set to a position higher than the upper surface of the mounting frame, the distance between the fulcrums of the weight portion (the distance between the through holes at both ends) is the distance between the fulcrums of the mounting frame. As the same dimension as (the interval between the through holes of the mirror mounting portion), by fastening the weight portion and the mirror mounting portion, the mirror can be fixed and the initial tension can be introduced at the same time. The initial tension can be further increased.

  Furthermore, if a tension applying member is attached to the upper surface of the mounting frame, the initial tension can be introduced to the mirror by the weight of the weight part even in a planar arrangement, making the manufacture easier, and in particular, mounting the mirror. When the portion is the side surface of the mounting frame, the manufacturing can be further facilitated.

  Further, if the rotation axis is provided at the center position in the length direction of the short side frame at a height position higher than the upper surface of the mounting frame and at substantially the same height position as the reflection surface of the mirror, the reflection plate The focal position of the reflecting surface position can be made substantially constant during the rotational arrangement after the installation of the plant using.

  Furthermore, if the base material of the reflective material is a steel material and a reflective film having a surface roughness Ra ≦ 0.015 μm is provided on the surface of the base material, a higher performance reflective plate can be obtained.

  Since the main configuration of the present invention has been described by the above-described embodiments (Embodiments 1 to 4) of the present invention, here, as the specific examples (Examples 1 to 4), the external dimensions of the mounting frame 20 A prototype example in which 1800 mm × 272 mm is set and the length of the long side of the reflecting surface of the mirror 10 is 1600 mm will be described. As described above, Examples 1 to 4 correspond to Embodiments 1 to 4, respectively.

[Example 1]
(1) Mirror The mirror 10 (reflecting material 11) is made of a stainless steel plate having a base plate width of 272 mm, a thickness of 0.05 mm, a length of 1600 mm, and a tensile strength of 400 MPa, and has a surface roughness on the surface. A reflective film of Ra 0.015 μm is provided. The reflective film contains aluminum in an amount of 90% by mass or more, and is formed by vapor deposition so that the film thickness becomes 0.2 μm or less. Further, a protective layer having a thickness of 0.5 μm using a silane coupling agent is provided on the surface of the reflective film. In order to reduce the roughness of the surface of the reflective layer (reflective film) and the protective layer, the stainless steel plate is previously treated by a composite polishing of paper polishing and electrolytic polishing. The thickness including the substrate and the reflective film is approximately 0.1 mm.

  At both ends on the long side of the reflector 11, stainless steel plates having a width of 50 mm, a length of 1600 mm, and a plate thickness of 2.3 mm are used as the plate-like bodies 12a and 12b of the weight portion 12. ) And fixed. The weight portion 12 has a center position in the width direction, a position of 25 mm and a position of 75 mm from both ends in the length direction, and an intermediate portion in the length direction at intervals of 100 mm, and the diameter of the joining bolt 24a is 6 mm. Is provided corresponding to the through hole 21b of the mirror mounting portion 21a.

  The mirror 10 is in contact with the mounting frame 20 only at a frame provided with the mirror mounting portion 21a (here, the two long side frames 21 facing each other), and the other frame (here, facing the mounting frame 20). The dimension is such that it does not come into contact with the two short side frames 22).

(2) Mounting frame The mounting frame 20 of the mirror 10 uses angle steel L-70 × 70 × 6 and length 172 mm for the short side frame 22, and angle steel L-50 × 50 × 4 for the long and short side frame 21. A length of 1800 mm is used. Thus, the mounting frame 20 having an outer shape of 272 mm × 1800 mm is configured.

  The long side frame 21 has its flange as an upper surface and the web is arranged toward the inside of the mounting frame 20, and the short side frame 22 has its flange as a lower surface and the web as an outer peripheral surface of the mounting frame 20. And, it is arranged so as to be sandwiched by the long side frame 21.

  Here, in a state where the mounting frame 20 is horizontally disposed, the side extending in the horizontal direction is referred to as a flange, and the side extending in the vertical direction is referred to as a web (hereinafter the same).

  The flange of the long side frame 21 is a mirror mounting portion 21a. At the center position in the width direction, the positions 25mm and 75mm from both ends in the length direction, and the intermediate portion in the length direction are Through holes 21b corresponding to the diameter 6 mm of the joining bolt 24a are provided at intervals of 100 mm, and correspond to the through holes 12c of the weight portion 12 described above.

  Further, on the inner surface of the long side frame 21, angle steel L-30 × 30 × 4 is used as a tension applying member support portion 33 to be described later, with the flange as an upper surface and the web in contact with the long side frame 21. The long side frame 21 is disposed over the entire length.

  Further, at the intermediate portion in the length direction of the long side frame 21, the reinforcing member made of angle steel L-50 × 50 × 4 is attached to both ends of the long side frame 21 in the length direction on the lower surface of the tension applying member support portion 33. It is arranged at a position of 500 mm from the part and a position of the middle part and fixed by welding. In addition, it is more preferable that a total of two reinforcing members arranged at the position of the intermediate portion are provided at a position of 50 mm on the left and right with the position as a center to have a stronger structure. Here, the reinforcing members are connected and fixed by welding, but they may be assembled using fasteners such as bolts and nuts.

  Moreover, in order to utilize this reflecting plate as a plate-like mirror for use in a linear Fresnel type, a diameter for attaching the rotary shaft 39 at a position 18 mm below the upper end of the central portion in the length direction of the short side frame 22. A 7 mm through hole is provided. This height position substantially coincides with the installation height position of the reflecting surface of the mirror 10.

(3) Tension applying member The tension applying member 31 is a stainless circular steel pipe having an outer diameter of 27.2 mm, a plate thickness of 2.3 mm, and a length of 1660 mm. At both ends in the length direction, through holes (bolt holes) 31b having a diameter of 7 mm that penetrate vertically are provided at positions 15 mm from the respective ends. On the lower surface, through holes 31a having a diameter of 7 mm are provided at positions of 40 mm, 215 mm, and 615 mm from the above through holes 31b, respectively, and adjustment bolts 35 can be inserted.

  Here, the stainless steel round steel pipe is used for the tension applying member 31, but a normal steel pipe subjected to anticorrosion treatment or a resin member having necessary strength and rigidity may be used. Also, the cross-sectional shape is not circular, and a closed cross-section member having an arcuate upper surface and a flat surface on the other surface may be combined with a metal or resin part having an arcuate upper surface on the upper surface of a square steel pipe. . Furthermore, even a member having one of the side surfaces having an open cross section can be used as long as it has a predetermined rigidity.

  In addition, the through holes 31a provided on the lower surface are adjusted in quantity and arrangement interval as necessary. Further, since the through hole 31a functions as a guide (preventing deviation) between the tension applying member 31 and the adjustment bolt 35, if the function can be fulfilled, the through hole 31a is not necessarily a through hole, and may be locally or It is good also as a concave shape over the full length. Therefore, all forms can be used as long as the form is a substantially hat shape, etc., with the lower part being an open cross section and the insertion part of the adjusting bolt 35 being provided.

(4) Supporting portion of tension applying member As described above, on the inner surface of the long side frame 21, as the tension applying member supporting portion 33, the chevron L-30 × 30 × 4 has its flange as the top surface, and the web The long side frame 21 is arranged over the entire length so as to be in contact with the long side frame 21. The height position of the upper surface of the flange is a position 25 mm lower than the upper surface of the long side frame 21. As a result, the tension applying member 31 and the rear surface of the mirror 10 are kept in a non-contact state in the initial assembly state.

  On the upper surface (flange) of the tension applying member support portion 33, a through hole having a diameter of 7 mm is located at a position of approximately 13.5 mm from the inside of the long side frame 21 and at a position of 85 mm from both ends in the length direction of the long side frame 21. (Bolt holes) 33b are provided, and further, female screw portions 33a having a nominal diameter of 6 mm are provided at positions 40 mm, 215 mm, and 615 mm from the through holes 33b, and adjustment bolts 35 are arranged upward on the respective female screw portions 33a. Yes.

  The adjustment bolt 35 has a length of 40 mm, is built in the tension applying member 31 and is in contact with the back side of the upper surface thereof, and the tension adding member 31 is moved upward by tightening the adjusting bolt 35. I can do it.

  When the adjustment bolt 35 directly pushes up the lower surface of the tension applying member 31 without providing the through hole 31a on the lower surface of the tension applying member 31, the length of the adjustment bolt 35 ensures a necessary amount of increase. It can be as long as possible.

  In order to constrain the movement of the tension applying member 31 toward the inner central portion direction of the long side frame 20 (the central direction of the short side frame 22), the long side frame 21 of the tension applying member support portion 33 is restrained. Separately, a plate material (restraint portion 34) having a height of 25 mm and a plate thickness of 3 mm is attached to the flange of the tension applying member support portion 33. The plate material may be continuous in the longitudinal direction.

  In addition, if the arrangement | positioning of the tension application member support part 33 is comprised as a form which makes a flange a lower surface and the flange front-end | tip contacts the long side frame 21, a standing side (web) will be arrange | positioned in the inner center part side of the long side frame 20 Since it can, it becomes the restraint part 34 and the said board | plate material is unnecessary.

(5) Installation of tension applying member The tension applying member 31 is arranged on the mounting frame 20 prior to the mounting of the mirror 10.

  A through hole 31 a on the lower surface of the tension applying member 31 is inserted into the adjustment bolt 35. Further, a joint bolt nut 32 (joint bolt 32a, joint nut having a neck length of 50 mm and an outer diameter of 6 mm is inserted into the through holes 31b at both ends of the tension member 31 and the through holes 33b at both ends of the tension member support part 33. 32b). At that time, the joining nut 32 b is attached so as not to restrain the upward movement of the tension applying member 31. This prevents the tension applying member 31 from falling off.

  As described above, if the movement of the tension applying member 31 toward the inner side of the long side frame 21 is restricted, the tension applying member 31 is held by the tension of the mirror 10 and the pushing force of the adjustment bolt 35. The joining bolt nut 32, the bolt hole 31b, and the bolt hole 33b for fixing the tension applying member can be omitted.

(6) Mirror mounting When the mirror 10 is mounted, it is desirable to maintain a state where tension is introduced so that plastic deformation does not occur in the mirror 10 (reflecting material 11).

  One mirror joint portion 15 (weight portion 12) and one mirror mounting portion 21a are previously fastened by a joint bolt nut 24 (joint bolt 24a, joint nut 24b) having a nominal diameter of 6 mm, and the mirror joint portion 15 is directed upward. The mounting frame 20 is rotated and held so that the other mirror joint portion 15 is on the lower side, and the reflecting surface of the mirror 10 (reflecting material 11) is separated by the weight of the mirror joint portion 15 (weight portion 12) on the lower side. After forming a state in which tension is introduced to the mirror 10 (reflecting material 11) by applying a vertically downward force in parallel, the joint bolt nut is similarly applied to the mirror joining portion 15 (weight portion 12) which is located below. 24 (joining bolt 24a, joining nut 24b) is fastened and fixed.

  When attaching the mirror 10, it is preferable to use a pressing plate 23 having a plate thickness larger than that of the weight portion 12 and a plane dimension of about the weight portion 12. Here, the pressing plate 23 uses a stainless steel plate having a width of 40 mm, a length of 1600 mm, and a thickness of 3.2 mm, and has a through hole (bolt hole) 23 a corresponding to the through hole 12 c of the weight portion 12. . The holding plate 23 acts as an additional weight by sandwiching the mirror joining portion 15 (weight portion 12) between the holding plate 23 and the mirror mounting frame 21a.

  Further, in order to prevent damage when the mirror 10 is mounted, it is desirable to lift one weight portion 12 vertically so that the outer surface thereof is the upper side, and to dispose the other weight portion 12 below the mirror 10. Thus, the weight of the weight portion 12 disposed below the mirror 10 keeps a state in which a vertically downward tension is introduced in parallel with the reflecting surface of the mirror 10, and the mounting frame 20 is attached to the mirror mounting portion 21a. The plane is held so as to be substantially perpendicular to the horizontal plane, and the weight portion 12 above the mirror 10 is fixed by a joining bolt nut 24 having a nominal diameter of 6 mm. At this time, the joining nut 24b is temporarily tightened with the upper surface side, and the entire mounting state is confirmed and fixed by performing final tightening. Thereafter, the weight portion 12 which is located below is also fixed in the same manner.

  Here, the position of the upper surface of the tension applying member 31 is a marginal position that does not interfere with the rear surface of the mirror 10 in the arrangement state of the mirror 10. Since the mirror 10 is not in contact with the mounting frame 20 at a portion other than the parallel mirror joint 15, it is only necessary to manage unidirectional torsion and deflection in terms of accuracy management.

(7) Introduction of additional tension In the state up to this point, a substantially uniform initial tension is introduced into the mirror 10 and a certain level of plane is constructed. However, the material length changes due to thermal expansion and contraction or external force (wind load, etc.). In consideration of tension fluctuations based on the above, by introducing additional tension in the same direction as the introduced tension, a higher level of flatness can be ensured, and the plane of the mirror can be stably maintained Can do.

  The additional tension is introduced by tightening the adjusting bolt 35 and bringing the tip of the adjusting bolt 35 into contact with the back side of the upper surface of the tension applying member 31 and then further tightening the adjusting bolt 35 to raise the tension adding member 31. To do.

  When additional tension is introduced in a state where the entire length of the long side frame 21 is supported, all the adjustment bolts 35 are adjusted to have the same protruding length. The amount of rotation of the adjustment bolt 35 is generally managed, and then fine adjustment is performed so that the required flatness is obtained by visual observation or using a laser displacement meter.

  However, in reality, since the long side frame 21 is supported by the short side frame 22, it is necessary to consider the bending of the long side frame 21 in the length direction. In other words, correction is performed for the bending in the convex direction on the lower side that maximizes the central portion of the long side frame 21. Here, the protruding length of the adjusting bolt 35 at the center portion of the long side frame 21 is made larger than the protruding length of the adjusting bolt 35 at the end portion, and more specifically, the center portion becomes the largest and protrudes as it goes to the periphery. Keep the length short. Thereby, even if the long-side frame 21 is deformed downward, the tension applying member 31 can be kept linear and the plane of the reflecting surface of the mirror 10 can be held.

Here, one index for the tension (introduction tension) introduced into the mirror 10 is shown. Here, the sum of the introduced tension, the external force applied, and the maximum value of the temperature stress in the assumed temperature range is the 0.2% offset yield strength or yield point of the base material of the reflector 11 (14,000 N / m ² when 280 N / mm ² is assumed). The introduction tension was examined so as to be smaller than. The wind load was assumed to be 3000 N / m. When the effective mirror width in consideration of the distance between fulcrums by the tension applying member 31 is about 250 mm, the working wind force is 750 N / m, and the increase in strain is about 0.01 mm. And if the temperature fluctuation in use condition is 50 degreeC, the maximum value of the temperature stress degree in actual use is 123 N / mm < ² >, and expansion-contraction is 0.09 mm (distortion degree 0.0006). The tension giving this degree of distortion is 6150 N / m, and the total value of the stress generated in the usage situation is 6900 N / m. Here, the difference from the 0.2% offset strength is 7100 N / m. If the temperature stress degree maximum value is regarded as the temperature stress degree fluctuation range, it also means that the introduction tension is reduced by a maximum of 6150 N / m due to thermal expansion. Therefore, from the above, 6900 N / m or more, which is a tension that fluctuates due to temperature change, is introduced, and 7100 N / m, which is the difference between the mirror proof stress and the maximum value of working stress (total of wind load and maximum temperature stress), is calculated. Since it is managed as the upper limit value, if the introduction tension is set to about 7000 N / m, the mirror can maintain the tension and can hold the flat surface in an elastic state.

  In addition, although the above evaluated by excluding the thermal expansion of the mounting frame 20 as evaluation on the safety side, when the material of the mounting frame 20 is made of the same material as the base material of the reflector 11, the mounting frame 20 also expands and contracts in substantially the same manner, and the temperature stress only needs to be considered in terms of the difference between the solar radiation absorptivity and the long wavelength emissivity of the mirror 10 and the mounting frame 20, and in this case, the required initial tension is greatly reduced. can do.

  The tension management may be managed by attaching a strain gauge to each mirror, or may be managed by a relationship between the tightening amount of the adjusting bolt 31 and the mirror distortion by a separate experiment. A predetermined striking force may be applied to 10 and may be managed by the frequency or attenuation of the striking sound generated at that time.

[Example 2]
About the reflector shown in Example 1, the initial height position of the upper surface of the tension applying member 31 is set to be equal to or higher than the height position of the upper surface of the long side frame 21 and the mechanical means (joining bolt nut 24) of the mirror joining portion 15 is fastened. Accordingly, a case where the mirror 10 is fixed and the initial tension is introduced simultaneously will be described. The description of the same parts as those in the first embodiment is omitted here.

(4) Supporting portion of tension applying member On the inner surface of the long side frame 21, angle steel L-30 × 30 × 4 is used as the tension applying member supporting portion 33, the flange is the top surface, and the web is the long side frame 21. It arrange | positions over the full length of the long side frame 21 so that it may contact | connect. The height position of the upper surface of the flange of the tension applying member support portion 33 was set to a position 22 mm lower than the upper surface of the long side frame 21.

  Thereby, the height position of the upper end of the tension applying member 31 protrudes about 5 mm from the upper surface of the long side frame 21 in the attached state, and further, further than the upper surface of the plate-like body 12b disposed on the back surface of the reflector 11. It protrudes by about 3 mm and becomes a height position where the reflecting material 11 is pushed up by 3 mm.

  Note that the amount of protrusion at the upper end of the tension applying member 31 is calculated by calculating in advance the relationship between slippage at bolt holes 12c and 21b, which will be described later, and the necessary tension and strain, and causing the reflecting material 11 to change the required material length. The amount of protrusion may be obtained in advance, or the required protrusion amount may be confirmed in advance by the method of the first embodiment, and thereafter, the amount may be protruded in advance.

(6) Mirror mounting Although the same method as in Example 1 is used, the mirror joint 15 to be mounted first is temporarily fixed. At this time, the joint bolt 24a is in contact with the lower end of the bolt hole 21b of the mirror mounting portion 21a by sliding, and the joint bolt 24a is in contact with the upper end of the bolt hole 12c of the mirror joint portion 15. The mirror joining portion 15 on the lower side of the mirror 10 is constructed so as to be separated from the bolt hole 21b of the mirror mounting portion 21a by the tension applying member 31 that protrudes and is arranged. By tightening the nut 24b, the reflecting material 11 is pulled and fixed with the joining bolt nut 24, and initial tension introduction and mirror fixing are performed simultaneously, and a state in which the initial tension is introduced in the fixed state is constructed.

(7) Introduction of additional tension Although an appropriate initial tension has been introduced in the above-described process, fine adjustment is performed with each adjustment bolt 35 in order to further increase the flatness.

  FIG. 11 is a drawing-substituting photograph showing the reflector in Example 2.

[Example 3]
About the reflector shown in Example 1, 2, the position of the tension addition member 31 is made higher, and the example attached to the upper surface of the long side frame 21 is demonstrated. The description of the same parts as those in the first and second embodiments is omitted here.

(1) Mirror Considering the size of the tension applying member 31, the distance between the fulcrums of the mirror joint 12 (the distance between the bolt holes 12c at both ends) is adjusted. As a guide, when the radius of the tension applying member 31 is d and the circumferential ratio is π, the tension adding member 31 is increased by about (π−2) d. Here, since it is about 15.5 mm, the width | variety of the original plate of the reflecting material 11 shall be 287 mm.

(2) Mounting frame The width of the upper surface of the pair of long side frames 21 is configured to extend 30 mm in the inner side direction of the long side frame 21. The tension applying member support portion 33 shown in the first embodiment may be installed at the same height as the upper surface of the long side frame 21.

(6) Mirror mounting Although the method of the second embodiment may be used, the tension applying member 31 protrudes upward in this case, so that the fixing frame 20 can be fixed even if the mounting frame 20 is returned to the horizontal. The state in which the initial tension is introduced into the mirror 10 by the weight of the weight portion 12 can be maintained using the upper end portion of the tension applying member 31 as a fulcrum. Then, the joining bolt 24a is inserted into the bolt holes 21b, 12c, and 23a, and the joining nut 24b is tightened, so that the mirror 10 is pulled and fixed with the joining bolt nut 24, and initial tension introduction and mirror fixing are performed simultaneously.

  Furthermore, even when the mounting frame 20 is held horizontally from the beginning, it can be easily mounted by the same action.

[Example 4]
An example in which the mirror mounting portion 21a is used as the side surface of the long side frame 21 will be described for the reflector shown in the third embodiment. In addition, about the same part as Example 3, description is abbreviate | omitted here.

(1) Mirror The mirror 10 (reflecting material 11) is made of a stainless steel plate having a base plate width of 326 mm, a thickness of 0.05 mm, a length of 1600 mm, and a tensile strength of 400 MPa, and has a surface roughness on the surface. A reflective film of Ra 0.015 μm is provided. The reflective film contains aluminum in an amount of 90% by mass or more, and is formed by vapor deposition so that the film thickness becomes 0.2 μm or less. Further, a protective layer having a thickness of 0.5 μm using a silane coupling agent is provided on the surface of the reflective film. In order to reduce the roughness of the surface of the reflective layer (reflective film) and the protective layer, the stainless steel plate is previously treated by a composite polishing of paper polishing and electrolytic polishing. The thickness including the substrate and the reflective film is approximately 0.1 mm.

  At both ends on the long side of the reflector 11, stainless steel plates having a width of 50 mm, a length of 1600 mm, and a plate thickness of 2.3 mm are used as the plate-like bodies 12a and 12b of the weight portion 12. ) And fixed. The weight portion 12 has a center position in the width direction, a position of 25 mm and a position of 75 mm from both ends in the length direction, and an intermediate portion in the length direction at intervals of 100 mm, and the diameter of the joining bolt 24a is 6 mm. Is provided corresponding to the through hole 21b of the mirror mounting portion 21a.

  The mirror 10 is in contact with the mounting frame 20 only at a frame provided with the mirror mounting portion 21a (here, the two long side frames 21 facing each other), and the other frame (here, facing the mounting frame 20). The dimension is such that it does not come into contact with the two short side frames 22).

(2) Mounting frame The mounting frame 20 of the mirror 10 uses angle steel L-70 × 70 × 6 and length 272 mm for the short side frame 22, and angle steel L-50 × 50 × 4 for the long and short side frame 21. A length of 1800 mm is used. Thus, the mounting frame 20 having an outer shape of 272 mm × 1800 mm is configured.

  The long side frame 21 has its flange as an upper surface and the web is directed toward the outside of the mounting frame 20, and the short side frame 22 has its flange as a lower surface and the web becomes the outer peripheral surface of the mounting frame 20. And it has arranged so that it may contact | abut on the web lower surface of the long side frame 21, and may be pinched | interposed (an external dimension is the same as Example 1).

  The web of the short side frame 22 is additionally provided with a steel plate rotating bearing in which a through hole having a diameter of 7 mm is arranged at a height position 15 mm below the upper end. A hole may be provided.

  Furthermore, the upper surface of the long side frame 21 is used as the tension support member support portion 33, and the bolt hole 33b and the female screw portion 33a in the tension application member support portion 33 described in the first embodiment are provided at a position 13 mm from the outer surface.

  On the side of the long side frame 21, at the center position in the height direction, the position of 125mm and 75mm from both ends, and the middle part in the length direction corresponds to the diameter of 6mm of the joining bolt 24a at 100mm intervals. A through-hole 21b is provided to form a mirror mounting portion 21a.

  Further, at the intermediate portion in the length direction of the long side frame 21, the reinforcing member made of angle steel L-50 × 50 × 4 is attached to both ends of the long side frame 21 in the length direction on the lower surface of the tension applying member support portion 33. It is arranged at a position of 500 mm from the part and a position of the middle part and fixed by welding. In addition, it is more preferable that a total of two reinforcing members arranged at the position of the intermediate portion are provided at a position of 50 mm on the left and right with the position as a center to have a stronger structure. Here, the reinforcing members are connected and fixed by welding, but they may be assembled using fasteners such as bolts and nuts.

(3) Tension applying member The tension applying member 31 is a stainless circular steel pipe having an outer diameter of 34 mm, a plate thickness of 3.2 mm, and a length of 1660 mm. At both ends in the length direction, through holes (bolt holes) 31b having a diameter of 7 mm that penetrate vertically are provided at positions 15 mm from the respective ends. On the lower surface, through holes 31a having a diameter of 7 mm are provided at positions of 40 mm, 215 mm, and 615 mm from the above through holes 31b, respectively, and adjustment bolts 35 can be inserted.

(4) Support section of tension applying member As described above, the tension applying member support section 33 is provided on the upper surface of the long side frame 21.

(5) Installation of tension applying member The tension applying member 31 is arranged on the mounting frame 20 prior to the mounting of the mirror 10.

  A through hole 31 a on the lower surface of the tension applying member 31 is inserted into the adjustment bolt 35. The bolt hole 31b of the tension applying member 31 and the female thread portion 33a of the tension applying member supporting portion 33 are located at a position of 13 mm from the outer surface of the long side frame 21, and a circular steel pipe having an outer diameter of 34 mm is used for the tension applying member 31. Therefore, in the arrangement state, the side end portion of the tension applying member 31 is located 4 mm outside the outer surface of the long side frame 21. The bolt holes 31b at both ends of the tension applying member 31 are provided with a joining bolt nut 32 having a neck length of 55 mm and a diameter of 6 mm so that the joining nut 32b does not restrain the upward movement of the tension applying member 31. Install it. This prevents the tension applying member 31 from falling off.

  As described above, if the movement of the tension applying member 31 toward the inner side of the long side frame 21 is restricted, the tension applying member 31 is held by the tension of the mirror 10 and the pushing force of the adjustment bolt 35. The joining bolt nut 32, the bolt hole 31b, and the bolt hole 33b for fixing the tension applying member can be omitted.

(6) Mirror mounting Since the tension applying member 31 protrudes upward and the mirror mounting portion 31a is arranged vertically, the mounting frame 20 is held horizontally.

  One weight portion 12 is lifted vertically so that the outer side surface thereof is the upper side, and the other weight portion 12 is disposed below, so that the weight of the weight portion 12 located below is parallel to the reflecting surface of the mirror 10. In addition, a state in which a vertically downward tension is introduced is maintained, and the weight portion 12 (mirror joint portion 15) located below the tension portion is aligned with one mirror mounting portion 21a to join a joint bolt nut 24 having a nominal diameter of 6 mm. Fixed by. Then, the weight portion 12 that has been lifted is moved so that the mirror 10 covers the pair of tension applying members 31, and the mirror 10 is stretched while being pulled.

  Thereby, the state in which the initial tension is introduced to the mirror 10 by the weight of the weight portion 12 can be maintained with the upper end portion of the tension applying member 31 as a fulcrum.

  Here, as described above, since the side end portion of the tension applying member 31 is located 4 mm outside the outer side surface of the long side frame 21, the mirror joining portion 15 and the mirror mounting portion 21a are formed of a plate-like body. This is a state in which a gap of about 2 mm is opened by subtracting a plate thickness of 2.3 mm of 12b.

  Then, by inserting the other joining bolt 24a and tightening the nut 21b, the mirror 10 is pulled and fixed with the joining bolt nut 24, and initial tension introduction and mirror fixing are performed simultaneously.

DESCRIPTION OF SYMBOLS 1 Reflector 10 Mirror 11 Reflector 12 Weight part 12a Plate-shaped body 12b Plate-shaped body 12c Through-hole (bolt hole)
15 Mirror joint part 20 Mounting frame 21 Long side frame 21a Mirror mounting part 21b Through hole (bolt hole)
22 Short side frame 23 Holding plate 23a Through hole (bolt hole)
24 Joining bolt nut 24a Joining bolt 24b Joining nut 31 Tension applying member 31a Through hole 31b Through hole (bolt hole)
32 Joining bolt nut 32a Joining bolt 32b Joining nut 33 Tension applying member support part 33a Female thread part 34 Restraint part 35 Adjustment bolt 39 Rotating shaft

Claims (9)

A mirror having a reflector made of a rectangular metal sheet as a base material and a pair of weight portions to which plate-like bodies are attached over substantially the entire length of both ends of the short side or both ends of the long side of the reflector When,
It has a short side frame or a long side frame corresponding to the short side or the long side of the reflector to which the plate-like body is attached, and the weight portion is joined to the upper surface or the side surface of the short side frame or the long side frame. A mounting frame having a flat surface portion to be attached using a nut and serving as a mirror mounting portion;
It is arranged on the inner side or the upper surface of the mirror mounting part, and is movable up and down, and the movement of the mounting frame is restricted to the inner side. A pair of tensioning members;
A screw portion provided at a predetermined interval in the length direction of the frame on the side having the mirror mounting portion, and an adjustment bolt disposed on the female screw portion with the screw tip side facing upward; A tension applying member supporting portion for supporting the additional member,
The mirror is disposed in a non-contact state with respect to the mounting frame at a portion other than the weight portion, and at least one of the weight of the weight portion, the lifting force of the tension applying member, and the joining bolt nut. The reflector is attached to the mounting frame in a state in which an initial tension is introduced using the reflector.   From the state where the initial tension is introduced and the mirror is attached to the mounting frame, the mirror is further tightened with the adjusting bolt and the tension applying member is moved upward to introduce additional tension. The reflecting plate according to claim 1, wherein the flat surface is held.   The protruding length of the adjusting bolt at the intermediate portion in the longitudinal direction of the tension applying member supporting portion is set to be equal to or longer than the protruding length of the adjusting bolt at the longitudinal end portion of the tension applying member supporting portion. 2. The reflector according to 2. The length of the adjustment bolt is longer than the cross-sectional height of the tension applying member,
The tension applying member is an open cross-section member or a closed cross-section member having an upper surface and a lower surface, and a through hole is provided on the lower surface at a position corresponding to the adjustment bolt of the tension applying member support portion. The adjustment bolt is inserted, a tip end of the adjustment bolt is housed in a cross section of the tension applying member, and a tip end of the adjusting bolt is brought into contact with the back side of the upper surface of the tension adding member. The reflecting plate in any one of 1-3.   A connecting member for connecting the frames on the side having the mirror mounting portion to each other at an intermediate portion in the length direction is disposed. The reflection plate according to any one of claims 1 to 4, wherein the distance is equal to or less than a part-side interval.   6. The reflector according to claim 1, wherein an initial height position of the upper surface of the tension applying member is set to a height position equal to or higher than the upper surface of the mounting frame.   The reflector according to claim 1, wherein the tension applying member is attached to an upper surface of the attachment frame.   The rotating shaft is provided at a height position higher than an upper surface of the mounting frame at a center position in a length direction of the short side frame and at a height position substantially the same as the reflecting surface of the mirror. Item 8. The reflector according to any one of Items 1 to 7.   The reflecting plate according to claim 1, wherein the reflecting material is made of steel, and a reflecting film having a surface roughness Ra ≦ 0.015 μm is provided on the surface of the substrate.