JP2008168110A - Scattered ray removing grid and manufacturing method for it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide structure and a manufacturing method for inexpensively and stably obtaining a scattered X-ray removing grid, which takes air as intermediate substance and accurately positions and holds an X-ray absorbing substance. <P>SOLUTION: A guide slit plate 2 provided with guide slits 2a formed parallel at a predetermined distance so that metal foils 3 as the X-ray absorbing substance disposed between them are fitted parallel to the primary X-ray is relatively fixed and disposed, and with both end parts of each metal foil 3 inserted in the opposite slits 2a of each guide slit plate 2, one end or both ends of each metal foil 3 are held in the state of being given tension by an energizing means (a tension coil spring or the like) 7 outside the slits, whereby each metal foil 3 can be accurately positioned and subjected to correction for deformation in the bending state due to its dead load or in the natural state to stably maintain the position, shape and attitude. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a scattered X-ray removal grid and a manufacturing method thereof, and more particularly to a scattered X-ray removal good using air as an intermediate substance and a manufacturing method thereof.

  For example, in medical and industrial X-ray fluoroscopic apparatuses and X-ray CT apparatuses, in general, an object and an X-ray detector are used for the purpose of preventing X-rays scattered by the object from entering the X-ray detector. A scattered X-ray removal grid is disposed between the two.

  This type of grid is composed of a large number of foil-shaped X-ray absorbing materials made of lead and the like, and an intermediate material as a spacer interposed between the foil-shaped X-ray absorbing materials. Arranged so as to be parallel to the primary X-ray. In a normal X-ray fluoroscopy device or X-ray CT device using an X-ray tube as a radiation source, the foil-like X-ray absorbing material is arranged so that the extension of each surface is focused on one straight line at the focusing distance A so-called focusing grid is used. A parallel grid in which the respective foil-shaped X-ray absorbing materials are arranged in parallel to each other may be used for special purposes.

  As the intermediate material, aluminum or paper fiber is frequently used, and those that are in practical use may be considered as any of these (for example, see Non-Patent Document 1).

  Here, since primary X-rays are also absorbed by aluminum or fiber used as an intermediate substance, it is necessary to increase the amount of X-ray exposure to the subject accordingly. In order to improve this, some grids using air as an intermediate substance have been proposed (see, for example, Patent Document 1).

In this proposal, a plurality of pins are arranged on the opposing portions of the frame body that forms the outer frame of the grid, spaced substantially in parallel with each other, and a tape as an X-ray absorbing material is applied to each pin. Adopts a structure that hangs around sequentially. In this proposal, the tape as the X-ray absorbing material is a tape made of polyethylene terephthalate resin coated with tungsten powder.
Noboru Iida “Easy Understanding of X-ray Grids” Journal of Japanese Society of Radiological Technology June 1999 pp 529-535 Japanese Patent Laid-Open No. 2002-40150

  By the way, by using air as an intermediate substance, it is clear that the absorption of primary X-rays by the grid is reduced and the exposure of the subject is reduced, but such a proposal including the above-mentioned Patent Document 1, In any case, there is no one that can accurately hold a metal foil or the like, which is an X-ray absorbing material, and can be stably produced at a low cost.

  The present invention has been made in view of such circumstances, and a scattered X-ray removing grid capable of accurately positioning and holding a metal foil as an X-ray absorbing material using air as an intermediate substance, and the grid It is an object to provide a method that can be stably manufactured at low cost.

  In order to solve the above-mentioned problems, the scattered X-ray removal grid of the present invention has a large number of metal foils as X-ray absorbing materials provided between them in parallel with each other at a predetermined distance. The guide slit plate formed with a large number of guide slits to be fitted in parallel with each other is relatively fixedly arranged, and the guide slit plates of the respective guide slit plates facing each other are arranged as described above. It is characterized in that one end or both ends of each metal foil are held in a state where tension is applied by a biasing means outside the slit in a state where both ends of the metal foil are inserted. ).

  Further, in the method for manufacturing a scattered X-ray removal grid according to the present invention, a plurality of metal foils as X-ray absorbing materials provided therebetween are parallel to each other at a predetermined distance and parallel to primary X-rays. A guide slit plate formed with a large number of guide slits to be fitted with each other is fixed and arranged relatively, and both ends of the metal foil are inserted into the guide slits of the guide slit plates facing each other. In this state, outside the slit, the urging means is engaged with both ends of each metal foil, or one end is fixed by the fixing means and the urging means is engaged with the other end to apply and hold the tension. Characterized by comprising steps (claim 2).

  Here, in the method for manufacturing a grid for removing scattered X-rays of the present invention, after the process according to claim 2, each metal foil or each guide slit is provided for each guide slit portion of each guide slit plate. It is possible to employ a method (Claim 3) in which the metal foils are bonded together with an adhesive in the vicinity of the portion.

  Further, after the process according to claim 2, a thin plate (for example, a carbon fiber sheet or an aluminum sheet) made of a light element is covered as a grid cover on the X-ray incident side and the X-ray emission side of each metal foil. The method of removing the urging means and fixing means of each metal foil after bonding, or cutting both ends of each metal foil inside the guide slit plate and taking it out from the guide slit plates on both sides (claims) 4) can be adopted.

  Here, in the method for producing the scattered X-ray removal grid of the present invention, instead of the guide slit plates, a pair of slit plates overlapped in the plate thickness direction is used, and the slit plates are After forming a large number of slits wider than the thickness of the metal foil, and inserting the metal foil into each slit, the pair of slit plates are shifted in the width direction of the slit to sandwich each metal foil and guide It is possible to adopt a method of (claim 5).

  In the method for producing a scattered X-ray removal grid of the present invention, a molybdenum foil can be used as the metal foil (Claim 6), or each guide slit is held and fixed as the metal foil. The surface of a material having a thermal expansion coefficient substantially equal to the material of the holding body to be plated can be used (claim 7).

  In the present invention, both ends of each metal foil as an X-ray absorbing material are fitted in guide slits parallel to each other, and tension is applied to one end or both ends by an elastic member outside the slit. The problem is to be solved by positioning each metal foil stably and accurately and regulating the posture.

  That is, a large number of metal foils as X-ray absorbing materials are usually as thin as several tens of μm, which makes it difficult to position the materials and to regulate postures such as bending and slack, and intermediate materials. It is one of the obstacles to making air. In the present invention, both end portions of each metal foil are sandwiched between guide slits arranged opposite to each other in parallel, and in that state, tension is applied to one end or both ends of each metal foil outside the slit. At the same time as positioning each metal foil reliably, postures such as bending and bending can be easily corrected.

  The invention which concerns on Claim 1 is a grid for scattered X-ray removal used in the above tension | tensile_strength provision state. The invention method according to claim 2 includes the steps until the invention according to claim 1 is manufactured. In the method according to the present invention, each metal foil is formed as in the invention according to claim 3. A method of adhering to each guide slit portion at the both ends with an adhesive or a method of adhering metal foils in the vicinity of each guide grid portion can be adopted, and after this step, the tension of each metal foil is adjusted. The providing means becomes unnecessary.

  Further, as in the invention according to claim 4, after the step of claim 2, a thin plate made of a light element (for example, a carbon fiber sheet or an aluminum sheet) is applied to the grid cover on the X-ray incident side and the emission side of each metal foil. After adhering as follows, remove one end of each metal foil outside the slit, or urging means and fixing means at both ends, or cut both ends of each metal foil inside the guide slit plate, and the grid cover If the bonded metal foil is taken out from the guide slit plates on both sides, the guide slit plate, its holding body, and urging means are not attached to the product. A grid can be manufactured.

  In addition, the guide slit of the guide slit plate used in the present invention has such a width that each metal foil can be inserted and positioned. As described above, the metal foil used in this type of grid is several tens of μm. If it is thin and it is not easy to form a guide slit that is wide enough to position it, or if it is expensive, a large number of guide slits that are considerably wider than the thickness of the metal foil, respectively, as in the invention according to claim 5 By overlapping the two slit plates having the slits in the thickness direction and shifting in the width direction of the slits, a guide slit having an arbitrary width can be formed by these two slit plates.

  The metal foil used in the manufacturing method of the present invention as described above applies tension in the state of being inserted into the guide slit as described above to regulate positioning and posture, but is suitable for such applications. As a material of the foil, a molybdenum foil can be cited as in the invention according to claim 6. Molybdenum has a relatively large X-ray absorption coefficient and density, so that it can absorb scattered X-rays reliably and at the same time has high elasticity and rigidity. Has the advantage that it is not easily deformed even in the manufacturing process.

  Further, as the material of the metal foil used in the present invention, as in the invention according to claim 7, a material whose thermal expansion coefficient is substantially equal to the holding body that holds and relatively fixes the guide slit plate, Using a tin-plated surface can produce a scattered X-ray removal grid that is less susceptible to the temperature of the operating environment when the product is manufactured with the guide slit plate and its holder included. This is preferable. In addition, even when metal foils are bonded to each other with an adhesive in the manufacturing process, the position and posture of the metal foil in the resulting product is stable and highly accurate, and is not easily affected by temperature changes in the manufacturing environment. be able to.

  According to the grid for removing scattered X-rays of the present invention, both ends of a large number of metal foils as X-ray absorbing materials are inserted into the respective guide slits of the guide slit plate fixed in parallel with each other, outside the slit. Since a grid using air as an intermediate material is realized by applying tension to each end of each metal foil by an urging means and holding each metal foil, aluminum or fiber is used as the intermediate material. Compared to the case, the transmittance of primary X-rays is improved, and the exposure amount of the subject can be reduced correspondingly. And since each metal foil is hold | maintained in the state which provided the tension | tensile_strength, it is correctly positioned in the state by which the bending by the own weight, the deformation | transformation of a natural state, etc. were corrected.

  In addition, since each metal foil is held in a state where one end or both ends are not fixed and are urged, in a conventional grid in which both ends are fixed, the metal foil and the frame are not changed when the temperature of the usage environment changes. In contrast to the grids according to the present invention, the biasing means such as a spring absorbs the above thermal expansion difference, whereas the metal foil has undergone a shape change such as bending due to the difference in thermal expansion. As a result, the metal foil is not deformed and the position, shape, and orientation are always kept constant, and the performance is not deteriorated.

  Moreover, according to the method for manufacturing a scattered X-ray removal grid of the present invention, the metal foil positioning and shape correction can be reliably performed in the manufacturing process, and the scattered X-ray removal grid using air as an intermediate substance is provided. It can be manufactured stably.

  In addition, when the environment temperature of the grid for removing scattered X-rays can be limited to a certain temperature range and the change in shape of the metal foil due to the difference in thermal expansion between the metal foil and the frame can be ignored in the temperature range, the above is performed. By fixing both ends of the metal foil that has been positioned and corrected for shape with an adhesive, the urging means can be removed, and the size and weight can be reduced accordingly.

  In addition, a thin plate made of a light element (for example, a carbon fiber sheet or an aluminum sheet) is placed on the primary X-ray incident side and the emission side of the metal foil in a state where the shape is corrected by being positioned by the guide slit and the biasing means. Adhere as a grid cover so as to cover each, in that state, remove the urging means and fixing means at one end of each metal foil or both ends, or cut both ends of the metal foil inside the guide slit plate If the metal foil to which the grid cover is bonded is taken out, a grid that is as compact as possible can be obtained, and at the same time, the guide slit plate, its holding body and urging means can be used repeatedly. Reduction can also be achieved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view of an embodiment in which the present invention is applied to a focusing grid. FIG. 2 is a perspective view of the upper and lower grid covers, and FIG. 2 is a cross-sectional view taken along line AA in FIG. The upper and lower grid covers are shown. FIG. 3 shows a schematic front view of the guide slit plate 2.

  Guide slit plates 2 each having a large number of guide slits 2a are arranged on two opposite sides of the rectangular frame 1, and X-rays are respectively applied to the guide slits 2a facing each other among the guide slits 2a. Both end portions of the metal foil 3 as an absorbing material are inserted.

  Each guide slit 2a is arranged so that the metal foil 3 inserted between them is parallel to the X-rays irradiated from the X-ray focal point F under a preset focal length (for example, 120 cm), and It is formed with an interval, a posture, and a length so as to have a set grid ratio (for example, 10). The width of each guide slit 2a is precisely machined by, for example, CN electric discharge machining so that the metal foil 3 can be inserted without play. In the front view of FIG. 3, the width of the guide slit 2a and the relationship between the pitch and the length of the guide slit 2a are wider than the actual width because of the constraints shown in the figure.

  Each metal foil 3 has rods 4 and 5 inserted into holes formed further on the tip side than the insertion portion in the state where both end portions thereof are inserted into the respective guide slits 2a of the guide slit plate 2. Is held by. The material of the metal foil 3 is not particularly limited as long as it has a required X-ray absorption coefficient. In this example, a molybdenum foil is used.

  Of the rods 4 and 5 described above, one rod 4 is fixed to the frame body 1 to form a fixed rod. Further, the other rod 5 is not fixed to the frame 1 and constitutes a tension rod 5.

  The tension rod 5 is urged in a direction away from the fixed rod 4 by a plurality of tension coil springs 7 whose one ends are engaged with a plurality of pins 6 provided on the frame body 1, respectively. 3 is tensioned. Although the number of tension coil springs 7 is not limited, the configuration in which one tension coil spring 7 is arranged for about 20 metal foils 3 also absorbs variations in the hole spacing of each metal foil. It is desirable that the fixing rod 4 be covered with a flexible tube (for example, a silicon tube) because a uniform tension can be applied to each metal foil 3.

  Grid covers 8 a and 8 b made of carbon fiber sheets are attached to the upper edge of each metal foil 3 and the lower surface of the frame 1, that is, the X-ray incident side and emission side, respectively.

  The assembly method of the above embodiment will be described. First, both end portions of the metal foil 3 are inserted into the opposing guide slits 2a, and then the fixing rod 4 is inserted into a hole formed at one end portion of the metal foil 3. And the tension rod 5 is passed through the hole formed in the other tip. Next, the tension coil spring 7 is engaged between the tension rod 4 and each pin 6, and finally grid covers 8a and 8b are attached.

  According to the embodiment described above, the scattered X-ray removal grid having high primary X-ray transmittance using air as an intermediate substance, and the metal foil 3 which is an X-ray absorbing substance is more highly accurate with the guide slit 2a. At the same time, the posture is regulated, and the deflection due to its own weight and the deformation in the natural state are corrected by the application of tension by the tension coil spring 7. Moreover, since each metal foil 3 is in a state in which one end side is not fixed and tension is applied, even if a difference in expansion occurs between the frame 1 and the metal foil 3 due to a change in the use environment temperature. Since the extension amount of the tension coil spring 7 absorbs the difference, the metal foil 3 is not deformed and always maintains a constant position, posture and shape, and the performance does not deteriorate.

  In addition, since the grid covers 8a and 8b are detachable so that the opposite side can be seen through the metal foil 3 when they are removed, the two-dimensional X-ray detector is used in combination with the two-dimensional X-ray detector. There is also an advantage that the position adjustment with the X-ray detector can be easily performed.

  Here, in the state shown in FIG. 1 in the above embodiment, both ends of each metal foil 3 are bonded to the guide slit plate 2 with an adhesive, or the metal foils 3 are mutually connected in the vicinity thereof. In this case, the tension coil spring 7 is no longer necessary, and the grid is in a state in which these are removed, or in which the pin 6 and a part of the frame 1 that supports the pin 6 are further excluded. It can be. The grid having such a configuration is effective when the use environment temperature is limited within a certain range. Further, the metal foil 3 as the radiation absorbing material is assumed to be a material having a thermal expansion coefficient close to that of the frame 1, for example, carbon steel which is the same material as the frame 1, and the surface thereof is tinned. For example, even if there is a change in the use environment temperature, a difference in thermal expansion does not occur. Therefore, even if each metal foil 3 is bonded and fixed with an adhesive, the metal foil 3 does not deform. In this case, carbon steel has an advantage that it is cheaper and easier to process than molybdenum.

  Moreover, in the above embodiment, although the example which fixed a pair of mutually parallel guide slit board 2 to the two opposite sides of the frame 1 was shown, each guide slit board is used without using the frame 1. Rods may be fixed to both ends of the two, and the two rods and the entire two guide slit plates 2 may be used as a rectangular frame. Furthermore, the grid covers 8 a and 8 b can be used as a holding body for fixing and holding the guide slit plate 2. Furthermore, as will be described later, when the final product is a grid for removing scattered X-rays that does not include a guide slit plate, a pair of guide slit plates is fixed to a metal plate or the like, and finally the metal plate and It is also possible to remove the guide slit plate.

Next, another embodiment of the present invention will be described.
FIG. 4 is a perspective view showing the manufacturing process, and FIGS. 5 and 6 are a plan view and a side view, respectively.

  In this example, a rectangular frame 1 is used as in the previous example, but instead of the guide slit plate 2 provided on the two opposite sides, a guide slit mechanism 20 is provided, and the tension coil spring 7 is provided. The manner of engagement with the frame 1 is different.

  Each of the tension coil springs 7 is engaged with a tension rod 5 inserted into a hole formed at the tip of the metal foil 3 in this example as in the previous example, but the other end is connected to the frame 1. The support rod 9 is fixed in parallel with the tension rod 5.

  In addition, as shown in FIG. 7A and a partially enlarged view of FIG. 7A, the guide slit mechanism 20 includes two pieces each having the same number of slits 20a formed at the same pitch. It consists of slit plates 21 and 22, and the width of the slit 20 a of each of the slit plates 21 and 22 is considerably wider than the thickness of the metal foil 3. Of these slit plates 21 and 22, one slit plate 21 is fixed to the frame 1, and the other slit plate 22 is fixed to the slit plate 21.

  That is, support members 23 and 24 are fixed to each of the other two sides orthogonal to the two opposite sides of the frame 1 where the guide slit mechanism 20 is arranged, and both ends of one slit plate 21 are It fixes to the edge part of the supporting member 23, and the other slit board 22 is being fixed with respect to the slit board 21 in the state piled up in the plate | board thickness direction. The slit plate 22 is screwed to the slit plate 21, and the screwing through hole has a necessary gap with respect to the screw, and the slit plate 22 has a predetermined gap with respect to the slit plate 21 within the gap. The position can be changed in the width direction of the slit 20a.

  In positioning the metal foil 3 by the slit mechanism 20 described above, first, the both ends of the metal foil 3 are inserted with the slit plates 21 and 22 in both the slit mechanisms 20 being substantially coincident with each other. After that, the slit plate 22 is moved in the width direction of the slit 20 a, the metal foil 3 is sandwiched between the slit plates 21 and 22 without any gap, and the slit plate 22 is fixed to the slit plate 21 in this state. As a result, each metal foil 3 is guided by the guide slit mechanism 20 in a state where there are no gaps at both ends thereof, and positional deviation due to vibration or the like is unlikely to occur, and the difficulty and cost of processing the slit 20a are the same as the previous example. This is reduced as compared with the case of processing the guide slit 2a.

  Now, with the metal foil 3 shown in FIG. 4 positioned and corrected in shape and posture, the metal foil 3 is equivalent to the previous example so as to cover the X-ray incident side and the emission side of the metal foil 3. After the grid covers 8a and 8b are directly bonded with an adhesive, the fixing means on one end side and the biasing means on the other end side are removed, or both ends of each metal foil 3 are cut inside the guide slit mechanism 20 Then, the metal foil to which the grid cover is bonded is taken out. Thereby, as shown in a side view in FIG. 8, a scattered X-ray removal grid composed of a large number of metal foils 3 and upper and lower grid covers 8a and 8b is obtained.

  In the thus obtained scattered X-ray removal grid, the metal foils 3 are bonded to each other in a state where the metal foils 3 are positioned by the guide slit mechanism 20 and tension is applied by the biasing means mainly composed of the tension coil spring 7. Therefore, it has the same position, shape, and posture accuracy as the previous example, and becomes a grid for removing scattered X-rays that is as compact as possible using air as an intermediate material, and the frame 1 and the guide slit mechanism. 20 and all of the biasing means including the tension coil spring 7 function as a jig and can be used repeatedly, and the cost as a grid can be greatly reduced.

  In the above embodiment, the example in which the pair of guide slit mechanisms 20 is attached to the frame 1 has been described. However, the guide slit mechanism 20 and the frame 1 are not attached to the final product as a jig. Therefore, it is not necessary to fix the guide slit mechanism 20 to the frame body 1. As described above, even if each guide slit mechanism 20 and the urging means are provided on, for example, a metal flat plate, there is no problem. Absent.

  Further, in each of the above embodiments, an example in which the present invention is applied to a focusing grid has been shown. However, the present invention is not limited thereto, and each metal foil can be applied to a parallel grid parallel to each other. Of course.

  Further, in each of the above embodiments, an example in which a tension coil spring is used as an urging means only at one end has been shown, but the present invention is not limited to this, and an urging means may be provided at both ends. Further, other elastic members or the like may be used as the urging means.

  An example in which an elastic sheet is used as an urging means for the metal foil 3 is shown in a perspective view of a main part in FIG. In the example of FIG. 9, each metal foil 3 as an X-ray absorbing material is urged by an elastic sheet 70.

  That is, one end of each elastic sheet 70 is fixed to one end of each metal foil 3, and a hole is made in the other end of each elastic sheet 70, and the support rod 9 is passed through each hole. Here, a reinforcing / engaging member 71 made of a metal plate is fixed around the hole of each elastic sheet 70 to improve the strength and prevent deformation, and is also supported by the reinforcing / engaging member 71. A hole for penetrating the rod 9 is formed concentrically with the hole of the elastic sheet 70.

  According to the above configuration, each metal foil 3 has a structure in which the tip portion and the tension rod 50 are connected by the elastic sheet 70 outside the guide slit plate 2, and the support rod 9 is connected to the guide slit plate 2 from the guide slit plate 2. By moving and fixing in the direction away from each other, a tensile load acts on each metal foil 3, and by appropriately selecting the fixing position and the elastic force of each elastic sheet 70, each metal foil 3 has a required value. A tensile force can be applied.

  Here, when the tension coil spring 7 is used as the urging means for the metal foil 3, it is necessary to bear a large number of the metal foils 3 with one tension coil spring 7. There is a possibility that a required tensile force cannot be applied to the individual metal foil 3 due to restrictions, and in such a case, the adoption of the configuration of FIG. 9 is effective.

  A more specific configuration of the embodiment of FIG. 9 will be described with reference to FIG. 10A is a perspective view showing the assembly process of the metal foil 3, the elastic sheet 70, and the reinforcement / engagement plate 71, and FIG. 10B is the “metal foil + elastic sheet” with holes created in FIG. FIG. 6 is a schematic plan view showing an assembled state that is passed through the support rod 9 through the guide slit plate 2. In this example, it is assumed that two elastic single-sided adhesive tapes 70a and 70b are bonded to each other as shown in FIG. 5A, and the adhesive surfaces of the respective tapes 70a and 70b are opposed to each other. In a state where the metal foil 3 and the reinforcing / engaging member 71 are sandwiched between the two, they are pressed from both sides and bonded to each other. As long as the elastic sheet 70 achieves the original purpose of applying tension to the metal foil 3, the elastic sheet 70 is not limited to the structure in which the two sheets are bonded together, and may be a single structure. Further, the material is not limited to the polyurethane resin of this example as long as a predetermined tensile strength can be obtained without variation for each sheet.

  The pitch of the metal foil 3 is about 0.59 mm, and by setting the thickness of the reinforcing / engaging member 71 to about 0.2 mm, the elastic sheet 70 and the entire reinforcing / engaging member 71 are more than the above pitch. Can also be thinned.

  Further, when the elastic sheet 70 is used as the urging means of the metal foil 3, by setting the elastic sheet 70 to an appropriate length, as shown in the front view of FIG. By using it, the elasticity of the sheet 70 functions well, and the positions of the metal foils 3 in the vertical direction can be aligned relatively easily. FIG. 11 shows a configuration in which elastic sheets 70 as urging means are provided at both ends. In this case, the reinforcing / engaging plate 71 is used at both ends, and the metal foil can be held with a stronger tensile force.

  Here, also in the case where the elastic sheet is used as the urging means, the grid covers are bonded to the incident side and the emission side of the primary X-rays in the positioning and urging states of the respective metal foils 3, and in this state, the respective metal foils 3. 8 or 8 by removing the urging means and the fixing means at both ends, or by cutting both ends of the metal foil 3 inside the guide slit plate and taking out the metal foil to which the grid cover is adhered. The compact grid shown in Fig. 1 is obtained.

It is a perspective view of an embodiment which applied the present invention to a focusing grid, and is a figure shown in the state which saw through the upper and lower grid covers. It is AA sectional drawing in FIG. 1, and the upper and lower grid covers are shown in the illustrated state. It is a typical front view of the guide slit board 2 in embodiment of FIG. It is a perspective view showing the manufacturing process of other embodiment of this invention. FIG. 5 is a plan view of FIG. 4. FIG. 5 is a side view of FIG. 4. 4A and 4B are explanatory views of the guide slit mechanism 20 in the embodiment of FIG. 4, in which FIG. 4A is a perspective view thereof, and FIG. It is a side view of the grid for scattered X-ray removal obtained by other embodiment of this invention. It is a principal part perspective view of further another embodiment of this invention. 9 is an explanatory diagram of a specific configuration of the embodiment of FIG. 9, (A) is a perspective view showing an assembly process of the metal foil 3, the elastic sheet 70 and the reinforcing / engaging plate 71, and (B) is obtained by (A). FIG. 6 is a schematic plan view showing an assembled state in which “metal foil + elastic sheet” is passed through the guide slit plate 2 and through the support rod 9. It is explanatory drawing of the example of the method of positioning to the up-down direction of metal foil in embodiment of FIG. 9, FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Frame 2 Guide slit board 2a Guide slit 3 Metal foil 31, 32 Jig for aligning the vertical direction of metal foil 4 Fixed rod 5 Tensile rod 6 Pin 7 Tensile coil spring 8a, 8b Grid cover 9 Support rod 20 Guide slit Mechanism 20a Slit 21, 22 Slit plate 70 Elastic sheet 70a, 70b Polyurethane single-sided adhesive tape 71 Reinforcement / engagement member

Claims (7)

  A large number of guide slits are formed in which a large number of metal foils as X-ray absorbing materials provided therebetween are fitted in parallel with each other at a predetermined distance so as to be parallel to the primary X-rays. The guide slit plates are relatively fixedly arranged, and the respective metal foils are disposed outside the slits with both ends of the metal foil inserted into the guide slits facing each other of the guide slit plates. A grid for removing scattered X-rays, wherein one end or both ends of the foil is held in a state where tension is applied by an urging means.   A guide in which a large number of guide slits are formed in which a plurality of metal foils as X-ray absorbing materials provided therebetween are fitted in parallel with each other at a predetermined distance so as to be parallel to the primary X-ray. The slit plates are relatively fixedly arranged, and both ends of the metal foil are inserted into the guide slits facing each other of the respective guide slit plates, and are attached to both ends of the respective metal foils outside the slit. A method of manufacturing a grid for removing scattered X-rays, comprising the steps of engaging a biasing means or fixing one end with a fixing means and engaging a biasing means with the other end to apply and hold a tension. Method.   After the process according to claim 2, each metal foil is bonded to each guide slit portion of each guide slit plate, or each metal foil is bonded in the vicinity of each guide slit portion with an adhesive. A method for manufacturing a grid for removing scattered X-rays.   After the step according to claim 2, the thin plates made of light elements are bonded to the X-ray incident side and the X-ray emission side of each metal foil as a grid cover so as to cover each, and then the biasing means for each metal foil And a method for producing a scattered X-ray removing grid, wherein the fixing means is removed, or both ends of each metal foil are cut inside the guide slit plate and taken out from the guide slit plates on both sides.   Instead of each guide slit plate, a pair of slit plates overlapped in the plate thickness direction is used, and each slit plate is formed with a number of slits wider than the thickness of the metal foil, 5. After inserting the said metal foil into a slit, the said metal foil is pinched | interposed and guided by shifting the said pair of slit board to the width direction of a slit, The any one of Claim 2, 3 or 4 characterized by the above-mentioned. A method for producing a grid for removing scattered X-rays as described in 1.   6. The method for manufacturing a scattered X-ray grid according to claim 2, wherein a molybdenum foil is used as the metal foil.   The metal foil is obtained by using a tin-plated surface of a material having a thermal expansion coefficient substantially equal to a material of a holding member that holds and fixes each of the guide slits. The method for producing a grid for scattered X-rays according to any one of 4 and 5.

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